KR20170004216A - Double-stage MR mount using flow mode and shear mode of magneto-rheological fluid - Google Patents

Double-stage MR mount using flow mode and shear mode of magneto-rheological fluid Download PDF

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Publication number
KR20170004216A
KR20170004216A KR1020150094260A KR20150094260A KR20170004216A KR 20170004216 A KR20170004216 A KR 20170004216A KR 1020150094260 A KR1020150094260 A KR 1020150094260A KR 20150094260 A KR20150094260 A KR 20150094260A KR 20170004216 A KR20170004216 A KR 20170004216A
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South Korea
Prior art keywords
disk
engine
shaft
housing
mount
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KR1020150094260A
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Korean (ko)
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KR101709994B1 (en
Inventor
최승복
도쑤웬푸
양순용
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인하대학교 산학협력단
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63H—MARINE PROPULSION OR STEERING
    • B63H21/00—Use of propulsion power plant or units on vessels
    • B63H21/30—Mounting of propulsion plant or unit, e.g. for anti-vibration purposes
    • B63H21/302—Mounting of propulsion plant or unit, e.g. for anti-vibration purposes with active vibration damping
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
    • F16F9/00—Springs, vibration-dampers, shock-absorbers, or similarly-constructed movement-dampers using a fluid or the equivalent as damping medium
    • F16F9/32—Details
    • F16F9/53—Means for adjusting damping characteristics by varying fluid viscosity, e.g. electromagnetically
    • F16F9/535—Magnetorheological [MR] fluid dampers
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
    • F16F2224/00—Materials; Material properties
    • F16F2224/04—Fluids
    • F16F2224/045—Fluids magnetorheological

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Ocean & Marine Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Vibration Prevention Devices (AREA)
  • Combined Devices Of Dampers And Springs (AREA)

Abstract

The present invention relates to a double-stage magneto-rheological (MR) mount using a shear mode and a flow mode of an MR fluid, which damps vibration generated by an engine of a vessel by being installed in the lower part of the engine of the vessel. The double-stage MR mount includes: a housing supporting the engine of the vessel and charged with the MR fluid inside; a first shaft passing through the upper part of the housing in the vertical direction and moving in the vertical direction by vibration of the engine of the vessel; a first disk installed in the lower part of the first shaft in the horizontal direction and integrally formed with the first shaft, wherein the first disk moves in the vertical direction by a vertical movement of the first shaft; a second shaft installed by vertically passing through the lower part of the housing and vertically moving by vibration of the engine of the vessel; a second disk arranged in the upper part of the second shaft in the horizontal direction and having a flow path of the horizontal direction between the first disk by being spaced at fixed intervals from the first disk in the lower part of the first disk, wherein the second disk vertically moves by a vertical movement of the second shaft; a first self-induction coil installed on the outer side of the first disk and generating a magnetic field to change a rheological property of the MR fluid flowing between the first disk and the second disk; and a second self-induction coil generating the magnetic field to change the rheological property of the MR fluid flowing between the second disk and an inner wall of the housing.

Description

{Double-stage MR mount using flow mode and shear mode of magneto-rheological fluid (MR)

The present invention relates to an MR mount for vibration reduction of a marine engine, and more particularly, to a dual-stage MR mount using a flow mode and a shear mode of a MR fluid capable of flexibly coping with both vibration will be.

Generally, the propulsion of the ship is performed by rotating the propeller shaft by the engine driving force due to the explosive force of the cylinder, so that the vibration is caused by various factors. Particularly, in the engine, periodic change of the center of gravity due to up and down movement and rotational movement of the piston and the connecting rod, inertial force of the reciprocating motion generated in the axial direction of the cylinder, inertial force caused by the connecting rod swinging to the left and right of the crankshaft, Vibration of the engine due to various factors such as the periodic change of the rotational force of the engine, and vibration of the engine must be suppressed in order to secure the safety of the ship and the life of various structures.

As a countermeasure for preventing the vibration of the marine engine, a method of mounting a vibration attenuating mount on the lower part of the marine engine is generally used.

The vibration attenuating mount of such a marine engine is divided into a friction type using friction and a hydraulic type using hydraulic.

However, the frictional mount has a merit that it is simple in construction, but it has a disadvantage in that it can not actively act on a vibration which varies depending on the load of the engine. Hydraulic mounts, on the other hand, have the advantage of being able to actively act on vibrations that vary with the engine load, compared to friction mounts.

Japanese Laid-Open Patent Publication No. 10-2014-0030909 discloses a vibration-damping mounting device for a marine diesel generator using an M fluid and an operation method thereof. The hydraulic MR mount disclosed in this prior art document can actively respond to vibrations varying with the load of the engine using MR fluids whose rheological properties are changed by the magnetic field. However, such a conventional MR mount is constituted by one magnetic induction coil, so that there is a problem that the resolution of the control performance deteriorates due to a large change of the damping force according to the current change, and thus energy is wasted.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a dual-stage MR mount using a flow mode and a shear mode of a MR fluid, which can flexibly cope with vibrations on both sides and large displacement.

In order to achieve the above object, the present invention provides an MR mount which is provided under the engine of a ship and attenuates vibrations generated from an engine of a ship, the MR mount comprising: housing; A first shaft installed vertically through the upper portion of the housing and movable in a vertical direction by the vibration of the engine of the ship; A first disk disposed horizontally below the first shaft and integrally formed with the first shaft, the first disk moving in the vertical direction by the vertical movement of the first shaft; A second shaft installed vertically through the lower portion of the housing and movable in the vertical direction by the vibration of the engine of the ship; A horizontal axis is formed between the first disk and the first disk at a predetermined distance from the first disk at a lower portion of the first disk, A second disk moving in a vertical direction by movement; A first magnetic induction coil installed outside the first disk to generate a magnetic field to change a rheological property of the magnetic flow fluid flowing between the first disk and the second disk; And a second magnetic induction coil installed outside the second disk to generate a magnetic field to change the rheological properties of the magnetic flow fluid flowing between the second disk and the inner wall of the housing.

Preferably, the upper portion of the housing is provided with a rubber or silicon top cover for supporting the engine of the ship.

In the meantime, the second disk has a through-hole passing through the center in a direction perpendicular to the center, and a communication path communicating with the through-hole is formed in the second shaft.

Preferably, a position restricting groove is formed in an inner bottom surface of the housing, and a position restricting pin inserted into the position restricting groove at a lower portion of the second disk to limit the descending distance and horizontal movement of the second disk .

In addition, the bottom surface of the first disk or the top surface of the second disk may be provided with a rubber or silicone breakage prevention pad.

The dual-stage MR mount using the flow mode and the shear mode of the MR fluid according to the present invention is capable of effectively damping vibrations by effectively coping with both small vibrations and large vibrations, .

FIG. 1 is a longitudinal sectional view schematically showing a dual-stage MR mount using a flow mode and a shear mode of a MR fluid according to the present invention,
FIG. 2 is a longitudinal sectional view schematically showing a dual-stage MR mount using a flow mode and a shear mode of a MR fluid according to the present invention,
3 is a cross-sectional view schematically illustrating a dual-stage MR mount using a flow mode and a shear mode of MR fluid according to the present invention.

Hereinafter, a preferred embodiment of a dual stage MR mount using the flow mode and the shear mode of the MR fluid according to the present invention will be described with reference to the accompanying drawings. In the following description of the present invention, it is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the technical scope of the present invention. Will be.

Referring to FIGS. 1 to 3, the dual-stage MR mount using the MR fluid flow mode and the shear mode according to the present invention is installed in the lower part of the engine of the ship to support the engine and attenuate vibrations generated from the engine of the ship A first magnetic induction coil 600 and a second magnetic induction coil 600. The apparatus includes a housing 100, a first shaft 200, a first disk 300, a second shaft 400, a second disk 500, And includes a coil 700.

The housing 100 is installed under the engine (not shown) of the ship to support the engine of the ship, and a magneto-rheological fluid, i.e. MR fluid, is filled therein.

Here, the magnetic flow fluid acts as a working fluid in the reciprocating motion of the first disk 300 and the second disk 500, which will be described later. These magnetic flow fluids emit fluids whose rheological properties (viscosity, plasticity, and elasticity) can be reversibly changed in response to the magnitude of the magnetic field. When the magnetic field strength increases, the yield stress increases to resist external motion . Specifically, a magnetic flow fluid, that is, a MR fluid, is a fluid whose yield stress and apparent viscosity change with the application of a magnetic field. In a magnetic field load, particles injected into the fluid induce polarization, The magnetic field is parallel to the magnetic field to form a loop of a fibrous structure to resist the movement of the fluid or the shear force externally applied, and the reaction is relatively fast and exhibits a reversible response to the magnetic field load.

Such magnetic flow fluids have been applied to various mechanical devices such as a harmonic attenuator, a vibration isolation system, a clutch, a brake, a friction device, and a robot arm since they can bring about simplification of various mechanical system design with excellent control performance.

The first shaft 200 is installed vertically through the upper portion of the housing 100. This first shaft 200 is installed so as to be movable in the vertical direction by the vibration generated in the engine of the ship.

The first disc 300 is a component integrated with the first shaft 200 and is disposed horizontally inside the housing 100 and rotatably supported by the first shaft 200 by the vertical movement of the first shaft 200. [ In the vertical direction.

The second shaft 400 is installed through the lower portion of the housing 100 in the vertical direction. The second shaft 400 is installed so as to be movable in the vertical direction by the vibration generated in the engine of the ship.

The second disk 500 is horizontally connected to the upper portion of the second shaft 400 and moves in the vertical direction together with the second shaft 400 by the vertical movement of the second shaft 400. The second disk 500 is formed in a container shape having an opened top surface and is spaced apart from the first disk 300 by a predetermined distance so as to be separated from the first disk 300 and the second disk 500, And a flow path in the vertical direction are formed. At this time, when the first disk 300 moves toward the second disk 500 due to the vibration of the ship engine, the magnetic flow fluid flowing in the vertical flow path is divided into a flow mode and a shear mode And the vibration of the engine is damped.

The first magnetic induction coil 600 is installed at the midpoint outside the first disk 300 to change the rheological property of the magnetic flow fluid flowing in the flow path between the first disk 300 and the second disk 500 To generate a magnetic field. The first magnetic induction coil 600 generates a magnetic field when vibration occurs in the engine of the ship.

The second magnetic induction coil 700 is installed at the midpoint outside the second disk 500 to change the rheological properties of the magnetic fluid flowing in the passage between the second disk 500 and the inner wall of the housing 100 To generate a magnetic field.

With this configuration, the MR mount according to the present invention is capable of suppressing the vibration of the engine by using the flow mode and the shear mode of the magnetic flow fluid flowing around the first magnetic induction coil 600 and around the second magnetic induction coil 700 Damping.

Specifically, when a small vibration on the urine occurs in the marine engine, the vibration is transmitted to the first shaft 200 through the upper cover 110 of the housing 100, Direction. Then, the first disk 300 integrally formed with the first shaft 200 also reciprocates in the vertical direction. At this time, the small vibration on the urine of the marine engine is not transmitted to the second axis 400.

The magnetic flow fluid between the first disk 300 and the second disk 500 is then increased in the yield stress due to the magnetic field of the first magnetic induction coil 600, (See the vertical direction arrow in Fig. 1) and the horizontal direction flow direction (see the horizontal direction arrow in Fig. 1). That is, the magnetic flow fluid between the first disk 300 and the second disk 500 in the magnetic field region of the first magnetic induction coil 600 moves in a flow mode and a shear mode. Accordingly, the magnetic flow fluid can effectively cope with the small vibration generated in the marine engine.

When a large vibration is generated on the large displacement in the marine engine, the vibration is transmitted to the first shaft 200 through the upper cover 110 of the housing 100, and at the same time, Lt; / RTI > Accordingly, vibration is transmitted from the first disk 300 to the second disk 500, and both the first disk 300 and the second disk 500 reciprocate in the vertical direction.

2, the magnetic flux fluid between the first disk 300 and the second disk 500 in the magnetic field region of the first magnetic induction coil 600 and the magnetic flux between the first magnetic induction coil 600 and the second magnetic induction coil 700, The magnetic flow fluid between the second disk 500 in the magnetic field region of the housing 100 and the inner wall of the housing 100 moves in the flow mode and the front end mode with the yield stress increased by the magnetic field ). Therefore, the magnetic flow fluid can effectively cope with a large vibration generated in the marine engine.

At this time, the vibration on the urine and the vibration on the large side can be sensed through a separate sensor (not shown), and the operation of the first magnetic induction coil 600 and the second magnetic induction coil 700 Is controlled. 1 and 2, a portion indicated by a dotted line around the magnetic induction coils 600 and 700 represents a magnetic field generated by the magnetic induction coil.

As described above, the dual stage MR mount using the flow mode and shear mode of the MR fluid according to the present invention effectively attenuates both the small vibration and the large vibration generated in the marine engine. Further, energy can be saved by selectively operating the magnetic induction coil according to the magnitude of the vibration.

On the other hand, by varying the rheological characteristics of the magnetic flow fluid by controlling the intensity of the current amount of the magnetic induction coils 600 and 700, a wide range of attenuation coefficients can be obtained. In addition, the magnetic induction coils 600 and 700 are designed to decrease the strength of the magnetic field when high-frequency vibrations (small displacement vibrations) of the engine occur and to increase the strength of the magnetic field when low-frequency vibrations Lt; / RTI >

Preferably, the upper lid 110 provided on the upper portion of the housing 100 may be made of rubber or silicone to reduce the vibration of the engine while supporting the engine of the ship. Such a rubber or silicon top cover 110 can support a ship engine of heavy load and high load and can relieve the limitation of the stiffness size of the top cover 110.

Preferably, the second disc 500 has a through-flow passage 510 passing through the center in a direction perpendicular to the center. The second shaft 400 has a communication path 410 communicating with the through-flow path 510. When the first disk 300 is moved toward the second disk 500 by the vibration of the marine engine by the through-flow passage 510 and the communication path 410, the first disk 300 and the second disk 500 Can flow through the second disk 500 through the through passage 510 and the communication passage 410 to the lower portion of the housing 100. [ Therefore, a smooth reciprocating motion is possible when the first shaft 200 and the first disk 300 move due to the vibration of the ship engine.

On the other hand, a position limiting groove 120 is formed on the inner bottom surface of the housing 100. The second disk 500 has a position limiting pin 520 extending downward and inserted into the position limiting recess 120. The position limiting groove 120 and the position limiting pin 520 serve to limit the descending distance and horizontal movement of the second disk 500. That is, the position restricting groove 120 and the position restricting pin 520 may restrict the horizontal movement of the second disk 500 while maintaining the interval between the housing 100 and the second disk 500.

A damage prevention pad 800 made of rubber or silicon is attached to the bottom surface of the first disk 300 or the top surface of the second disk 500. This is because when the first disk 300 moves toward the second disk 500 due to abrupt vibration of the ship engine and the first disk 300 and the second disk 500 collide with each other, It serves to prevent damage.

A sealing member 900 for hermetic sealing may be provided between the housing 100 and the second shaft 400 at the lower end of the housing 100.

The dual stage MR mount according to the present invention can reduce the radius of the housing 100 and the disks 300 and 500 and increase the length of the disks 300 and 500 by using a damper It is also possible to design.

The embodiments of the present invention described above are merely illustrative of the technical idea of the present invention, and the scope of protection of the present invention should be interpreted according to the claims. It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention as defined by the appended claims. It should be interpreted that it is included in the scope of right.

100: housing 110: upper cover
120: position restriction groove 200: first axis
300: first disk 400: second axis
410: communication path 500: second disk
510: Through-flow passage 520: Position limiting pin
600: first magnetic induction coil 700: second magnetic induction coil
800: breakage prevention pad 900: sealing member

Claims (5)

1. An MR mount provided at a lower portion of an engine of a ship for attenuating vibration generated from an engine of a ship,
A housing for supporting an engine of the ship, the housing being filled with magnetic fluid (MR) fluid;
A first shaft installed vertically through the upper portion of the housing and movable in a vertical direction by the vibration of the engine of the ship;
A first disk disposed horizontally below the first shaft and integrally formed with the first shaft, the first disk moving in the vertical direction by the vertical movement of the first shaft;
A second shaft installed vertically through the lower portion of the housing and movable in the vertical direction by the vibration of the engine of the ship;
A horizontal axis is formed between the first disk and the first disk at a predetermined distance from the first disk at a lower portion of the first disk, A second disk moving in a vertical direction by movement;
A first magnetic induction coil installed outside the first disk to generate a magnetic field to change a rheological property of the magnetic flow fluid flowing between the first disk and the second disk; And
A second magnetic induction coil disposed outside the second disk to generate a magnetic field to vary the rheological properties of the magnetic flow fluid flowing between the second disk and the inner wall of the housing; Dual stage MR mount using shear mode.
The method according to claim 1,
Wherein the upper portion of the housing is provided with a rubber or silicon top cover for supporting the engine of the ship.
The method according to claim 1,
Wherein the second disk is formed with a through-hole passing through the center in a direction perpendicular to the center, and a communication path communicating with the through-path is formed in the second shaft. The dual-stage MR Mount.
The method according to claim 1,
A position restricting groove is formed in an inner bottom surface of the housing and a position restricting pin is formed in a lower portion of the second disk to limit a descending distance and a horizontal movement of the second disk, Dual stage MR mount using fluid flow mode and shear mode.
The method according to claim 1,
Wherein an MR damper pad of rubber or silicon is attached to the bottom surface of the first disk or the top surface of the second disk.
KR1020150094260A 2015-07-01 2015-07-01 Double-stage MR mount using flow mode and shear mode of magneto-rheological fluid KR101709994B1 (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108547909A (en) * 2018-06-06 2018-09-18 广州大学 A kind of double direction shear type magneto-rheological grease damper
KR102090687B1 (en) * 2018-11-30 2020-03-18 인하대학교 산학협력단 Mr damper having both of flow mode operating structure and pinch mode operating structure
KR102091107B1 (en) * 2018-11-30 2020-03-19 인하대학교 산학협력단 Mr damper having flow mode and pinch mode operating structures
CN114135621A (en) * 2021-12-01 2022-03-04 重庆工商大学 High-sensitivity large-load self-adaptive buffer device based on controllable magneto-rheological technology

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20100077657A (en) * 2008-12-29 2010-07-08 인하대학교 산학협력단 Multi axis controllable hybrid active mount
KR101202001B1 (en) * 2010-09-15 2012-11-15 한국생산기술연구원 Fluid Damper for Supporting Load Having Bearing Member on Piston Head

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20100077657A (en) * 2008-12-29 2010-07-08 인하대학교 산학협력단 Multi axis controllable hybrid active mount
KR101202001B1 (en) * 2010-09-15 2012-11-15 한국생산기술연구원 Fluid Damper for Supporting Load Having Bearing Member on Piston Head

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108547909A (en) * 2018-06-06 2018-09-18 广州大学 A kind of double direction shear type magneto-rheological grease damper
KR102090687B1 (en) * 2018-11-30 2020-03-18 인하대학교 산학협력단 Mr damper having both of flow mode operating structure and pinch mode operating structure
KR102091107B1 (en) * 2018-11-30 2020-03-19 인하대학교 산학협력단 Mr damper having flow mode and pinch mode operating structures
CN114135621A (en) * 2021-12-01 2022-03-04 重庆工商大学 High-sensitivity large-load self-adaptive buffer device based on controllable magneto-rheological technology

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