JP7331481B2 - friction damper - Google Patents

Description

The present invention relates to a friction damper for damping vibrations of buildings, structures, and the like.

Patent Document 1 discloses a friction damper that is provided between two members that move relative to each other and dampens vibration caused by the relative movement of these members. The friction damper disclosed in Patent Document 1 will be briefly described below using the reference numerals used in Patent Document 1 in parentheses.

As described in Patent Document 1, an outer plate (30), a friction plate (40), an intermediate plate (20), a friction plate (40) and an outer plate (30) are stacked in order, and these bolts (50bh) and nuts (50). A through hole (30h) is formed in the outer plate (30), a long hole (20h) is formed in the intermediate plate (20), and a long hole (40h) is formed in the friction plate (40). It is When the two members connected by this friction damper move relative to each other, the outer plate (30) moves relative to the middle plate (20), and the bolt (50bh) moves between the outer plate (30) and the intermediate plate (20). Together they move in the longitudinal direction of the slots (20h, 40h). Then, a frictional force is generated at the contact surface between the friction plate (40) and the outer plate (30) and the contact surface between the friction plate (40) and the intermediate plate (20). Attenuates the vibration due to the relative movement of

JP 2012-102809 A

By the way, when applying the friction damper described in Patent Document 1 to a civil engineering structure, both ends of the friction damper need to be pin-joined to the object, and the elongated holes (20h, 40h) must be elongated in the longitudinal direction. Therefore, it is necessary to lengthen the stroke length of the bolt (50bh). In such a case, the bolt (50bh) will come into contact with the inner surfaces of the long holes (20h, 40h). Such contact causes two adverse effects:
First, a torque acts on the bolt (50bh), loosening the bolt (50bh).
Secondly, the bolt (50bh) is worn, the rust prevention treatment of the bolt is damaged, and the durability of the friction damper is lowered.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to prevent loosening of a bolt of a friction damper.

In order to solve the above problems, the friction damper includes a first movable plate, a friction plate, a sliding plate and a second movable plate, which are stacked in order, and the first movable plate, the friction plate, the sliding plate and the second movable plate. a fastener for tightening the movable plate, wherein the friction plate is fixed to the first movable plate, the sliding plate is fixed to the second movable plate, and the friction plate and the sliding plate are slidable relative to each other. wherein one of the pair of the friction plate and the first movable plate and the pair of the sliding plate and the second movable plate is formed with an elongated hole, and the other pair is formed with a bolt hole; A fastening body has a bolt inserted through the long hole and the bolt hole, a nut screwed onto the bolt, and a pipe through which the bolt is passed and accommodated in the long hole and the bolt hole. , the pipe prevents rotation of the bolt when the bolt moves in the longitudinal direction of the slot.

According to the above, when the bolt moves in the longitudinal direction of the long hole, the pipe prevents the bolt from rotating, so that loosening of the bolt can be prevented.

When the pipe is made of a material with a low coefficient of friction, the pipe tends to slide against the inner surface of the slot, the outer surface of the bolt, or both. Therefore, even if the pipe and the bolt move in the longitudinal direction of the long hole while the pipe is sandwiched between the inner surface of the long hole and the outer peripheral surface of the bolt, torque is not transmitted from the inner surface of the long hole to the bolt. Therefore, co-rotation of the pipe and the bolt can be prevented, and loosening of the bolt can be prevented.

When the pipe is made of synthetic resin, the pipe tends to slide against the bolt or the inner surface of the long hole. Therefore, when the pipe is sandwiched between the inner surface of the long hole and the outer peripheral surface of the bolt, when the bolt moves in the longitudinal direction of the long hole, torque is not transmitted from the inner surface of the long hole to the bolt, resulting in loosening of the bolt. can be prevented.

When the pipe has flexibility, the inner surfaces of the long hole and the bolt hole are less likely to be damaged by the pipe.

Preferably there is play between the pipe and the bolt.
Preferably, there is play between the pipe and the inner surface of the slot and between the pipe and the inner surface of the bolt hole.
As described above, if there is play on the inside and outside of the pipe, the state where the bolt is sandwiched between the outer peripheral surface of the bolt and the inner surface of the long hole does not occur frequently. Therefore, when the pipe and the bolt move in the longitudinal direction of the long hole, torque is not transmitted from the inner surface of the long hole to the bolt, and loosening of the bolt can be prevented.

According to the present invention, loosening of bolts can be prevented.

It is a side view of a bridge. FIG. 3 is a side view of a friction damper installed on a bridge; It is a III-III cross-sectional view. 4 is a cross-sectional view of a cut plane perpendicular to the cut plane of FIG. 3; FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, although various technically preferable limitations are attached to the embodiments described below in order to carry out the present invention, the scope of the present invention is not limited to the following embodiments and illustrated examples.

FIG. 1 is a side view showing a damping structure at the end of a bridge, and FIG. 2 is a side view showing a friction damper 10 included in the damping structure.
The damping structure has movable bearings 4 and friction dampers 10 . A movable bearing 4 is installed on the abutment 3, and a bridge girder 2 is supported on the movable bearing 4. - 特許庁The movable bearing 4 transmits the vertical load from the bridge girder 2 to the abutment 3 while allowing relative horizontal vibration of the bridge girder 2 with respect to the abutment 3 within a predetermined range. The movable bearing 4 is, for example, a laminated rubber bearing or a roller bearing. A friction damper 10 is installed between the abutment 3 and the bridge girder 2. - 特許庁The friction damper 10 dampens the vibration of the bridge girder 2 by converting the kinetic energy of the horizontal vibration of the bridge girder 2 into thermal energy. Note that the movable bearing 4 and the friction damper 10 may be applied to the abutment instead of the abutment 3.

A bracket 5 is fixed to the side surface of the abutment 3, and one end of the friction damper 10 is connected to the bracket 5 by a pin joint structure 6 so as to be rotatable about a vertical axis. A bracket 9 is fixed to the lower surface of the bridge girder 2, and the other end of the friction damper 10 is connected to the bracket 9 by a pin joint structure 8 so as to be rotatable about a vertical axis. Since both ends of the friction damper 10 are pin-joined in this way, the friction damper 10 can be displaced not only in the direction of the bridge axis but also in the direction perpendicular to the bridge axis due to vibration, shock, or the like. The direction perpendicular to the bridge axis is the direction perpendicular to the paper surface of FIGS. 1 and 2 .

FIG. 3 is a cross-sectional view showing the cutting point III--III shown in FIG. 2 as viewed in the direction of the arrow (bridge axis direction). FIG. 4 is a cross-sectional view of the fastening body 20 of the friction damper 10 taken along a cross section perpendicular to the cross section of FIG. As shown in FIGS. 3 and 4, the friction damper 10 includes a lower movable plate 11, a friction plate 12, a sliding plate 13, a middle movable plate 14, a sliding plate 15, a friction plate 16, an upper movable plate 17, and a plurality of fastening bodies. 20. Each fastener 20 has a high tension bolt 21 , a nut 22 , a washer 23 , a washer 24 , a disc spring laminate 25 , a bushing 26 , a washer 27 and a round pipe 28 . The disc spring laminate 25 is obtained by stacking a plurality of disc springs 25a. The lower movable plate 11 or the upper movable plate 17 corresponds to the first movable plate recited in the claims, and the middle movable plate 14 corresponds to the second movable plate recited in the claims.

The lower movable plate 11 , the friction plate 12 , the slide plate 13 , the middle movable plate 14 , the slide plate 15 , the friction plate 16 and the upper movable plate 17 are stacked in order and tightened by a plurality of fasteners 20 . Below, the lower movable plate 11, the friction plate 12, the sliding plate 13, the intermediate movable plate 14, the sliding plate 15, the friction plate 16, the upper movable plate 17 and the fastening member 20 will be described in detail.

The middle movable plate 14 is connected at its end to the bracket 5 by a pin joint structure 6 so as to be rotatable about a vertical axis, and extends from the pin joint structure 6 toward the pin joint structure 8 . On the other hand, the movable plates 11 and 17 have their ends connected to the bracket 9 by the pin joint structure 8 so as to be rotatable around the vertical axis, and extend from the pin joint structure 8 toward the pin joint structure 6 . A middle movable plate 14 is arranged between the lower movable plate 11 and the upper movable plate 17, and these movable plates 11, 14, 17 are parallel to each other. The movable plates 11, 14, and 17 are strip-shaped, and the length in the direction perpendicular to the paper surface of FIG. 3 is longer than the width in the direction perpendicular to the paper surface of FIGS. The direction perpendicular to the paper surface of FIG. 3 is the direction from the pin joint structure 6 to the pin joint structure 8, and this direction is also called the longitudinal direction of the movable plates 11, 14, and 17. As shown in FIG. Alternatively, a web of H steel may be used as the middle movable plate 14 and a web of channel steel may be used as the movable plates 11 and 17.

Slide plates 13 and 15 are superimposed on both sides of the middle movable plate 14, respectively. The sliding plates 13 and 15 are fixed to the central movable plate 14 by fasteners such as bolts and nuts. The slide plates 13 and 15 are made of corrosion-resistant metal such as stainless steel or titanium alloy.

A friction plate 12 is sandwiched between the slide plate 13 and the lower movable plate 11 . The friction plate 12 is fixed to the lower movable plate 11 by fasteners such as bolts and nuts. A friction plate 16 is sandwiched between the slide plate 15 and the upper movable plate 17 . The friction plate 16 is fixed to the upper movable plate 17 by fasteners such as bolts and nuts. The friction plates 12 and 16 are made of an organic friction material or an inorganic friction material. The friction plate 12 contacts the sliding plate 13, and sliding/dynamic friction may occur between the friction plate 12 and the sliding plate 13. - 特許庁The friction plate 16 contacts the sliding plate 15, and sliding/dynamic friction may occur between the friction plate 16 and the sliding plate 15. - 特許庁

A long hole 14a is formed in the middle movable plate 14 . The elongated hole 14a is elongated in the direction perpendicular to the paper surface of FIG. Similarly, the sliding plates 13 and 15 are formed with elongated holes 13a and 15a extending in the longitudinal direction of the intermediate movable plate 14, respectively. These elongated holes 13a, 14a, 15a are vertically overlapped.

The lower movable plate 11 is formed with a plurality of round bolt holes 11a. These bolt holes 11a are arranged at predetermined intervals in the longitudinal direction of the long holes 13a, 14a and 15a, and the plane connecting the central axes of these bolt holes 11a is substantially the center of the long holes 13a, 14 and 15a in the width direction. pass through Similarly, the friction plate 12, the friction plate 16 and the upper movable plate 17 are also formed with a plurality of bolt holes 12a, 16a and 17a, respectively. The bolt hole 11a, the bolt hole 12a, the bolt hole 16a and the bolt hole 17a overlap vertically.

Each high tension bolt 21 has a washer 23, a bolt hole 17a, a bolt hole 16a, an elongated hole 15a, an elongated hole 14a, an elongated hole 13a, a bolt hole 12a, a bolt hole 11a, a washer 24, a disc spring laminate 25, a bush 26 and a washer. 27 and screwed to the nut 22 . Since the elongated holes 13a, 14a, 15a are elongated in the longitudinal direction of the intermediate movable plate 14, the shafts of the high tension bolts 21 can move in the elongated holes 13a, 14a, 15a in the longitudinal direction. In particular, since the friction damper 10 is used for a bridge, the longitudinal direction of the long holes 13a, 14a, 15a is adjusted so that the stroke length of the shaft portion of the high-tension bolt 21 in the longitudinal direction of the long holes 13a, 14a, 15a becomes long. length is long.

A washer 23 is sandwiched between the head of the high tension bolt 21 and the upper movable plate 17 , a washer 24 is sandwiched between the lower movable plate 11 and the disc spring laminate 25 , and a bushing 26 is attached to the disc spring laminate 25 . , the disc spring laminate 25 is sandwiched between the flange of the bushing 26 and the washer 24 , and the washer 27 is sandwiched between the bushing 26 and the nut 22 .

By screwing the high tension bolt 21 into the nut 22, the high tension bolt 21 and the nut 22 are connected to the washer 23, the upper movable plate 17, the friction plate 16, the slide plate 15, the middle movable plate 14, the slide plate 13, and the friction plate. 12, the lower movable plate 11, the washer 24, the disk spring laminate 25, the flange of the bush 26 and the washer 27 are tightened. The disc spring laminate 25 is elastically deformed by the tightening axial force of the high-tension bolt 21 and nut 22 , and a spring reaction force substantially equivalent to the tightening axial force is applied from the disc spring laminate 25 to the high-tension bolt 21 and nut 22 . acts on The coned disc spring laminate 25 prevents loosening of the high tension bolt 21 and the nut 22, and suppresses sudden or specific changes in the tightening axial force due to vibration or impact to stabilize the tightening axial force. A frictional force corresponding to the tightening axial force is generated between the friction plate 12 and the sliding plate 13 and between the friction plate 16 and the sliding plate 15 .

When the lower movable plate 11 and the friction plate 12 move in the longitudinal direction of the middle movable plate 14 relative to the sliding plate 13 and the middle movable plate 14 due to vibration, impact, etc., a gap between the friction plate 12 and the sliding plate 13 occurs. slippage occurs. As a result, a dynamic frictional force is generated between the friction plate 12 and the sliding plate 13, and thermal energy is generated. Similarly, when a slip occurs between the friction plate 16 and the sliding plate 15, a dynamic frictional force is generated between the friction plate 12 and the sliding plate 13, thereby generating thermal energy. Therefore, relative horizontal vibrations of the slide plate 13, the middle movable plate 14 and the slide plate 15 with respect to the lower movable plate 11, the friction plate 12, the friction plate 16 and the upper movable plate 17 are damped.

With the high-tensile bolt 21 inserted into the round pipe 28, the round pipe 28 has bolt holes 17a, 16a, elongated holes 15a, elongated holes 14a, elongated holes 13a, bolt holes 12a, bolt holes 11a, and washers 24. and a hole in the bushing 26. The round pipe 28 can rotate relative to the shaft of the high tension bolt 21 . Furthermore, the round pipe 28 is also applied to the inner surfaces of the bolt hole 17a, the bolt hole 16a, the long hole 15a, the long hole 14a, the long hole 13a, the bolt hole 12a, the bolt hole 11a, the hole of the washer 24, and the hole of the bush 26. can rotate.

The inner diameter (diameter) of the round pipe 28 is longer than the diameter of the shaft portion of the high-tensile bolt 21 , and a slight play exists between the outer peripheral surface of the high-tensile bolt 21 and the inner peripheral surface of the round pipe 28 . The outer diameter (diameter) of the round pipe 28 is shorter than the diameters of the bolt holes 11a, 12a, 16a, 17a, the holes of the washer 24, and the holes of the bushing 26. There is a slight play between the inner surface of the hole 16a, the bolt hole 17a, the hole of the washer 24 and the hole of the bush 26 and the outer peripheral surface of the round pipe 28. Furthermore, the outer diameter (diameter) of the round pipe 28 is shorter than the width of the long hole 15a, the long hole 14a and the long hole 13a. There is a slight play between

The round pipe 28 is made of a sliding material having a low coefficient of friction with respect to the high tension bolt 21 or a sliding material having a low coefficient of friction with respect to the sliding plate 13 , the intermediate movable plate 14 and the sliding plate 15 . Alternatively, the round pipe 28 is made of a material having a low friction coefficient with respect to the high tension bolt 21 as well as the sliding plate 13 , the intermediate movable plate 14 and the sliding plate 15 . The round pipe 28 may in particular consist of a self-lubricating material. Such a round pipe 28 prevents rotation of the high tension bolt 21 and prevents loosening of the high tension bolt 21 . More specific description will be given below.

When the middle movable plate 14 is displaced in the direction perpendicular to the bridge axis relative to the lower movable plate 11 and the upper movable plate 17, the round pipe 28 engages the outer peripheral surface of the shaft of the high tension bolt 21 and the long holes 13a, 14a, 15a. sandwiched between the inner surface of When the high-tensile bolt 21 moves in the longitudinal direction of the middle movable plate 14 with the round pipe 28 sandwiched between the outer peripheral surface of the shaft of the high-tensile bolt 21 and the inner surfaces of the long holes 13a, 14a, 15a, A pipe 28 rolls on the inner surfaces of the long holes 13a, 14a, 15a. In such a case, if the round pipe 28 is made of a sliding material with a low coefficient of friction against the high tension bolt 21 , the inner surface of the round pipe 28 will slide against the outer peripheral surface of the high tension bolt 21 . Therefore, no torque is transmitted from the slide plate 13, the intermediate movable plate 14, and the slide plate 15 to the high tension bolt 21, and co-rotation of the high tension bolt 21 and the round pipe 28 can be prevented. Therefore, loosening of the high tension bolt 21 can be prevented.

When the round pipe 28 is made of a sliding material having a low coefficient of friction with respect to the slide plate 13, the intermediate movable plate 14 and the slide plate 15, the round pipe 28 is in contact with the outer peripheral surface of the shaft portion of the high tension bolt 21 and the long holes 13a and 14a. , 15a, the round pipe 28 slides against the inner surfaces of the long holes 13a, 14a, 15a. Therefore, no torque is transmitted from the slide plate 13, the intermediate movable plate 14, and the slide plate 15 to the high tension bolt 21, and co-rotation of the high tension bolt 21 and the round pipe 28 can be prevented. Therefore, loosening of the high tension bolt 21 can be prevented.

By the way, when the round pipe 28 is sandwiched between the outer peripheral surface of the shaft portion of the high tension bolt 21 and the inner surfaces of the long holes 13a, 14a, 15a, the slide plate 13, the intermediate movable plate 14 and the slide plate 15 It is in an environment where torque is easily transmitted from the high tension bolt 21 to the high tension bolt 21 . However, since play exists on the outside and inside of the round pipe 28, the state in which the round pipe 28 is sandwiched between the outer peripheral surface of the shaft portion of the high tension bolt 21 and the inner surfaces of the long holes 13a, 14a, 15a is It doesn't happen often, and it doesn't last long. In other words, the frequency of occurrence of a state in which torque is transmitted from the slide plate 13, the intermediate movable plate 14 and the slide plate 15 to the high tension bolt 21 is low. Therefore, it is difficult for torque to be transmitted from the slide plate 13, the intermediate movable plate 14, and the slide plate 15 to the high tension bolt 21, and co-rotation of the high tension bolt 21 and the round pipe 28 can be prevented. Therefore, loosening of the high tension bolt 21 can be prevented.

The round pipe 28 may be made of a flexible material. Therefore, even if the round pipe 28 collides with the inner surfaces of the bolt holes 17a, 16a, 15a, 14a, 13a, 12a and 11a, the inner surfaces are less likely to be damaged.

Examples of materials for the round pipe 28 include synthetic resin (eg, fluororesin or phenolic resin), rubber, stainless steel, or paper. In particular, when the round pipe 28 is made of fluororesin, the round pipe 28 has a low coefficient of friction. When the round pipe 28 is made of phenolic resin, the round pipe 28 has a low coefficient of friction and high heat resistance. When the round pipe 28 is made of stainless steel, it is easy to prevent the bolt holes 17a, 16a, 15a, 14a, 13a, 12a and 11a from being damaged.

Although the friction damper 10 was used for a bridge in the above embodiment, it may be used for other civil engineering structures (eg, a viaduct). Friction dampers 10 may also be utilized in building structures.
In the above embodiment, the lower movable plate 11, the friction plate 12, the sliding plate 13, the middle movable plate 14, the sliding plate 15, the friction plate 16, and the upper movable plate 17 are stacked in this order, and the sliding plates 13 and 15 are the middle movable plate. Friction plate 12 was fixed to lower movable plate 11 and friction plate 16 was fixed to upper movable plate 17 . On the other hand, lower movable plate 11, sliding plate 13, friction plate 12, middle movable plate 14, friction plate 16, sliding plate 15, and upper movable plate 17 are stacked in this order. 14 , the slide plate 13 may be fixed to the lower movable plate 11 , and the slide plate 15 may be fixed to the movable plate 17 . In this case, the friction plates 12 and 16 are formed with elongated holes, and the sliding plates 13 and 15 are formed with a plurality of bolt holes. Also, in this case, the middle movable plate 14 corresponds to the first movable plate recited in the claims, and the lower movable plate 11 or the movable plate 17 corresponds to the second movable plate recited in the claims.
Also, other elastic members may be used instead of the disc spring laminate 25 . For example, the bushing 26 is inserted inside the coil spring, the coil spring is sandwiched between the flange of the bushing 26 and the washer 24, and the coil spring is compressed by the tightening axial force of the high tension bolt 21 and the nut 22. A reaction force may act on the high tension bolt 21 and nut 22 from the coil spring.
Further, the elastic member such as the coned disc spring laminate 25 may not be provided, and furthermore, the bush 26 or the washer 27 or both of them may not be provided as necessary. In this case, the high tension bolt 21 and the nut 22 consist of a washer 23, an upper movable plate 17, a friction plate 16, a slide plate 15, a middle movable plate 14, a slide plate 13, a friction plate 12, a lower movable plate 11, a washer 24, and a bush 26. and a washer 27 (however, the bush 26 or the washer 27 or both of them may be absent in some cases).

DESCRIPTION OF SYMBOLS 11, 14, 17... Movable plate 12, 16... Friction plate 13, 15... Slide plate 13a, 14a, 15a... Long hole 11a, 12a, 16a, 17a... Bolt hole 28... Round pipe

Claims (6)

a first movable plate, a friction plate, a sliding plate and a second movable plate, which are stacked in order;
a fastening body that tightens the first movable plate, the friction plate, the sliding plate, and the second movable plate;
the friction plate is fixed to the first movable plate, the sliding plate is fixed to the second movable plate, the friction plate and the sliding plate are slidable relative to each other;
one of the pair of the friction plate and the first movable plate and the pair of the sliding plate and the second movable plate is formed with an elongated hole, and the other pair is formed with a bolt hole;
The fastening body
a bolt inserted through the long hole and the bolt hole;
a nut screwed onto the bolt;
a pipe through which the bolt is passed and accommodated in the long hole and the bolt hole;
The pipe is flexible and a friction damper that prevents rotation of the bolt when the bolt moves in the longitudinal direction of the slot. 2. A friction damper according to claim 1, wherein said pipe is made of a material with a low coefficient of friction. 3. A friction damper according to claim 1, wherein said pipe is made of synthetic resin. the pipe is made of stainless steel
Friction damper according to claim 1 or 2. 5. A friction damper according to any preceding claim, wherein there is play between the pipe and the bolt. 6. A friction damper according to any one of the preceding claims, wherein there is play between the pipe and the inner surface of the slot and between the pipe and the inner surface of the bolt hole.

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