JPS624937A - Buffering method employing hysteresis and damper - Google Patents

Abstract

PURPOSE:To increase a vibration damping effect on vibration of a relatively low cycle, by a method wherein motion energy of vibration is consumed by a hysteresis loss incurring due to relative rotation between a hysteresis material and permanent magnets, positioned facing the hysteresis material. CONSTITUTION:A hysteresis material 6, having a high hysteresis loss, is secured to a screw shaft 4 being a rotary body, and plural permanent magnets 7 are secured to its outer periphery at intervals. Further, the magnetic poles on the hysteresis material 6 side of the plural permanent magnets 7 are aligned in a manner to be alternately different. A hysteresis loss incurs due to relative rotation between the hysteresis material 6 and the permanent magnets 7, and consumes motion energy of vibration. This is not influenced by a vibration velocity, resulting in production of a sufficient vibration damping effect even on vibration of a relatively low cycle.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention is used to protect supported bodies such as piping systems from vibrations caused by earthquakes, etc. in power plants, chemical plants, etc. The present invention relates to a vibration damping method for supporting a support body in a vibration-isolating manner, or to an improvement of a damper used as a vibration damper for that purpose.

(Prior Art) Conventionally, this type of damper converts linear relative motion caused by vibration between a supported body and a support body into rotational motion of a rotating body using a ball screw, nut, etc. A type of motor is known in which the rotation of this rotating body rotates a generator, the electromotive force is returned to the generator, and the generator acts as a motor that reverses the rotation, thereby performing a vibration damping effect.

(Problems to be Solved by the Invention) In the conventional damper described above, since the vibration energy loss is proportional to the rotational speed of the generator, the energy loss during low cycle vibration is small. For this reason, there is a problem in that it is not possible to obtain a damping effect of 1° against relatively low cycle vibrations.

The present invention aims to solve the above-mentioned conventional problems and provide a damping method that can obtain a sufficient damping effect even for relatively low-cycle vibrations, and a damper therefor.

(Means for Solving the Problems) In the present invention, in order to solve the conventional problems described in -, the relative displacement between the supported body and the support body is controlled by a hysteresis material 6 and a permanent magnet facing the hysteresis material 6. 7, and kinetic energy is consumed by the hysteresis loss accompanying the relative movement between the two to provide a buffering effect.

In addition, in order to embody the buffering method described in Th, either one is connected to a supported body such as a piping system, and the other is connected to a supporting body such as a structure, and the vibration between the supported body and the supporting body is connected. Two supporting members 1 and 2 that are relatively movable in the axial direction in response to displacement, and a ball cage that converts the relative displacement between the two supporting members 1 and 2 into rotational motion of a rotating body such as a hair cutting shaft 4. , a converter such as a nut 3,
A hysteresis material 6 is fixed to either one of a rotating body such as the screw shaft 4 or a spaced apart from the rotating body, and a plurality of permanent magnets 7 are fixed to the other side, and the hysteresis material 6 and the permanent magnets 7
and the permanent magnet 7 so as to be able to rotate relative to each other.
The damper was constructed by arranging the magnetic poles on the side of the hysteresis material 5 in alternately different ways.

(Function) When a slow relative movement (approximately 1 to 2 μ/sec) occurs between the support body and the supported body due to thermal displacement, the rotating body rotates extremely slowly via the conversion device. . In this case, the co-movement of the rotating bodies is hardly restricted, and therefore relative displacement between the supporting body and the supported body is reasonably allowed.

On the other hand, if a sudden vibration occurs between the supporting body and the supported body due to an earthquake or the like, the rotating body such as the screw shaft 4 starts rotating at high speed, and the hysteresis material 6 and the permanent magnet 7 A relative rotation occurs between the two. The hysteresis material 6 is magnetized by a permanent magnet 7 facing it. However, due to the relative rotation between the two, the hysteresis material 6 is affected by changes in the magnetic field and tends to shift its polarity. Focusing on a certain part of the hysteresis material 6, changes in its magnetic polarity draw a hysteresis loop, and energy corresponding to the area surrounded by this loop is consumed as heat. That is, the hysteresis loss consumes the kinetic energy of vibration, and the magnetic resistance caused by residual magnetism imparts torque to the rotating body, thereby obtaining a braking effect on the rotating body.

(Example) The main cylinder 1, which is one of the supports, has a large diameter part 1a and a small diameter part 1.
It has b. The outer end of the large diameter portion has a handle 1c.

Small diameter part] The b end is open.

The auxiliary cylinder 2, which is the other supporting member, has a handle 2a at its outer end, and its inner end is inserted into the main cylinder small diameter portion 1b so as to be freely axially removable and removable. The sub cylinder 2 has a ball nut 3 at its inner end.

A screw shaft 4, which is a rotating body, is rotatably supported at an intermediate portion within the main cylinder 1, and is screwed into a pole nut 3 of the sub-cylinder 2 within the small diameter portion 1b of the main cylinder. The ball nut 1-3 and the screw shaft 4 constitute a converting device that converts linear motion into rotational motion.

Further, a yoke material 5 is fixed to the screw shaft 4 within the main cylinder large diameter portion la, and a hysteresis material 6 is further attached to the outer periphery of the yoke material 5.
is fixed. The hysteresis material 6 is made of a material with relatively large hysteresis loss.

A plurality of permanent magnets 7 are fixed to the inside of the main cylinder large diameter portion 1a. The permanent magnets 7 are arranged such that their inner magnetic poles are alternately different.

Next, the operation of this embodiment will be explained.

This damper is used by connecting either the main cylinder 1 or the sub-cylinder 2 to a supported body and the other to a support body through handles 1c and 2a, respectively.

When the hysteresis material 6 rotates slowly due to slow displacement between the supporting body and the supported body due to thermal displacement, etc., the change in magnetic polarity is a slow one, so the magnetic resistance due to residual magnetism This hardly occurs, and therefore, slow relative displacement of the supported body is reasonably tolerated.

On the other hand, when the relative displacement between the supporting body and the supported body is sudden, such as during an earthquake, the hysteresis material 6 rotates at a relatively high speed. At this time, the magnetization polarity of the hysteresis material 6 by the permanent magnet 7 is determined by residual magnetism.
It is not possible to change following the change in the opposing permanent magnet 7, causing magnetic resistance and kinetic energy being consumed due to hysteresis loss. For this reason, rotational resistance is generated against the screw shaft 4, and this becomes a vibration damping force.

In other embodiments shown in FIGS. 3 to 5, a hysteresis material 6 as well as a disc-shaped yoke material 10 are fixed to the screw shaft 4 in the main cylinder large diameter part la, and the main cylinder large diameter part 1a inside 1
Annular permanent magnet 11 with magnetic poles arranged at both ends in the axial direction
is fixed. The opposing protrusions 12a of the pair of opposing annular yoke members 12, which are fixed to sandwich the permanent magnet 11, sandwich both sides of the disc-shaped yoke member 10 with a slight interval therebetween. The other configurations are substantially the same as those of the previous embodiment, and the same components are given the same reference numerals throughout.

In the case of this embodiment, in addition to the same effect as in the previous embodiment, an eddy current is generated in the disc-shaped yoke material 10 due to the rotation of the screw shaft 4, and this eddy current loss also serves to attenuate vibration energy at the same time. It performs the additional action of being able to do something.

Note that the present invention is not limited to the embodiment shown in FIG. They may be placed facing each other. Further, the shape of each supporting member such as the main cylinder 1 and the sub-cylinder 2 does not matter, and the means for converting the linear motion between the supporting members into the rotational motion of the rotating body is
Many other equivalents are available.

(Effects of the Invention) As explained above, in the present invention, the relative displacement between the supported body and the supporting body is converted into the relative rotational movement between the hysteresis material and the permanent magnet facing the hysteresis material, Due to hysteresis loss caused by relative movement between the two, kinetic energy is consumed to provide a buffering effect. And screw shaft 4
A hysteresis material 6 is placed on one side of a rotating body such as a rotating body, or in the vicinity thereof at a distance, and a plurality of permanent magnets 7 are placed on the other side.
were fixed to each other, the hysteresis material 6 and the permanent magnet 7 were opposed to each other so as to be able to rotate relative to each other, and the magnetic poles on the hysteresis material side 5 of the permanent magnet 7 were arranged to be alternately different, thereby constructing a damper. As a result, the loss of vibration energy is not affected by the speed of vibration, and it is possible to increase the loss of vibration energy during relatively low-cycle vibrations. Therefore, a sufficient damping effect for relatively low-cycle vibrations can be achieved. This has the effect of providing a buffering method that is effective and a damper that implements the method.

[Brief explanation of the drawing]

Figure 1 is a vertical front view, Figure 2 is a sectional view taken along line nn in Figure 1,
FIG. 3 is a longitudinal sectional front view of another embodiment, and FIG. 4 is a vertical sectional view of another embodiment.
FIG. 5 is a sectional view taken along line n--n in FIG. 1. 1... Main cylinder (supporting member), 2... Sub-cylinder (supporting member)
, 3... Ball nut (conversion device), 4... Screw shaft (rotating body), 6... Hysteresis material, 7... Permanent magnet. Patent applicant: Sanwa Detsuki Co., Ltd. 2nd F. 1 7) J (Kyu C1 cup (-1 12a sr.

Claims (2)

[Claims] (1) The relative displacement between the supported body and the supporting body is converted into a relative rotational motion between the hysteresis material and the permanent magnet facing it, and kinetic energy is generated by the hysteresis loss caused by the relative movement between the two. A buffering method that uses hysteresis to provide a buffering effect. (2) two support members, one of which is connected to the supported body and the other to the support body, and which are movable relative to each other in the axial direction in response to relative displacement between the supported body and the support body; A damper comprising a conversion device that converts the relative displacement between the two supporting members into rotational motion of the rotating body, wherein a hysteresis material is provided on either the rotating body or in the vicinity of the rotating body at a distance, and a hysteresis material is provided on the other side. A damper characterized in that a plurality of permanent magnets are fixed to each other, the hysteresis material and the permanent magnets are opposed to each other so as to be able to rotate relative to each other, and the magnetic poles of the permanent magnets on the hysteresis material side are arranged to be alternately different.