CN114576301B - Double-channel magnetorheological damper with large adjustable range - Google Patents
Double-channel magnetorheological damper with large adjustable range Download PDFInfo
- Publication number
- CN114576301B CN114576301B CN202210307472.6A CN202210307472A CN114576301B CN 114576301 B CN114576301 B CN 114576301B CN 202210307472 A CN202210307472 A CN 202210307472A CN 114576301 B CN114576301 B CN 114576301B
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- bobbin
- damper
- end cover
- magnetic conduction
- inner cylinder
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- 239000012530 fluid Substances 0.000 claims abstract description 16
- 238000004804 winding Methods 0.000 claims description 38
- 230000005284 excitation Effects 0.000 claims description 5
- 239000000463 material Substances 0.000 claims description 4
- 230000009977 dual effect Effects 0.000 claims 2
- 238000000034 method Methods 0.000 claims 1
- 238000013016 damping Methods 0.000 abstract description 21
- 238000007789 sealing Methods 0.000 description 6
- 230000018109 developmental process Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000000149 penetrating effect Effects 0.000 description 2
- 230000004323 axial length Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 238000010008 shearing Methods 0.000 description 1
Classifications
-
- 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
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- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Mechanical Engineering (AREA)
- Fluid-Damping Devices (AREA)
Abstract
A double-channel magnetorheological damper with a large adjustable range relates to a damper. The piston rod is provided with an end cover I, a piston head and an end cover II, a damper shell is arranged between the end cover I and the end cover II, a magnetic conduction inner cylinder is arranged outside the piston head, a bobbin is arranged outside the magnetic conduction inner cylinder, an exciting coil, an internal resistance magnetic strip and an external resistance magnetic strip are arranged on the bobbin, the bobbin is connected with a positioning plate, the positioning plate is connected with the damper shell and the magnetic conduction inner cylinder, a gap is arranged between the positioning plate and the end cover I or the end cover II, the positioning plate is provided with a through hole I, the magnetic conduction inner cylinder is provided with a through hole II, a magnetorheological fluid flow passage is formed between the bobbin and the magnetic conduction inner cylinder, between the bobbin and the damper shell and inside the magnetic conduction inner cylinder, and the through hole I and the through hole II are used for communicating the magnetorheological fluid flow passage. The invention improves the maximum controllable damping force of the magneto-rheological damper, reduces zero-field damping force, further improves the damping force adjusting range, can generate effective magnetic fields in two channels by single-coil energization, has simple control and improves the utilization rate of the magnetic fields.
Description
Technical Field
The invention relates to a damper, in particular to a double-channel magnetorheological damper with a large adjustable range.
Background
The magnetorheological damper manufactured by using the magnetorheological fluid is a typical semi-active actuator, and has the characteristics of adjustable damping force, low power consumption, high response speed, high reliability and the like, and is widely paid attention to. Through years of development, magneto-rheological dampers have been successfully applied to the fields of aerospace, construction, machinery and the like. Different application environments have different requirements on the performance of the damper, so magnetorheological dampers with various structural forms are also produced.
In certain applications, it is desirable that magnetorheological dampers be capable of providing a sufficiently large controllable damping force. The size of the magnetorheological damper is usually enlarged or a plurality of magnetorheological dampers are connected in parallel to improve the size of the controllable damping force, but the cost of increasing the weight and the volume is sometimes unacceptable, so that the application of the magnetorheological damper in a specific environment is limited, and the performance requirements of light weight, miniaturization and large controllable damping force adjustment range are also met for the magnetorheological damper.
In order to meet the development requirement of the magneto-rheological damper and expand the application range of the magneto-rheological damper, it is very necessary to design a new magneto-rheological damper structure so that the magneto-rheological damper has the performance of adjustable damping force in a large range under the conditions of space and weight limitation.
Disclosure of Invention
In order to solve the problems in the background technology, the invention provides a double-channel magnetorheological damper with a large adjustable range.
The invention adopts the following technical scheme: a double-channel magnetorheological damper with a large adjustable range comprises an end cover I, a damper shell, a positioning plate, an external resistance magnetic strip, a winding tube, a piston rod, an internal resistance magnetic strip, a piston head, an excitation coil, a magnetic conduction inner cylinder and an end cover II;
the outer side of the piston rod is sequentially and coaxially sleeved with a first end cover, a piston head and a second end cover, a damper shell is fixedly arranged between the first end cover and the second end cover, and the damper shell is coaxially sleeved on the outer side of the piston rod; the outer side of the piston head is coaxially sleeved with a magnetic conduction inner cylinder, the outer side of the magnetic conduction inner cylinder is coaxially sleeved with a winding tube, an excitation coil is wound on the winding tube, the inner end of the winding tube is provided with an inner resistance magnetic strip, the outer end of the winding tube is provided with an outer resistance magnetic strip, two ends of the winding tube are respectively and fixedly connected with corresponding positioning plates in a coaxial manner, the outer end of each positioning plate is connected with the inner wall of the damper shell, the inner end of each positioning plate is connected with the outer wall of the magnetic conduction inner cylinder, two positioning plates are coaxially sleeved on the outer side of the piston rod in a ring manner, gaps are reserved between each positioning plate and an adjacent end cover I or end cover II, each positioning plate is provided with a plurality of through holes I, the outer walls of two ends of the magnetic conduction inner cylinder are provided with a plurality of through holes II, and an inner throttling channel is formed between the inner wall of the winding tube and the outer wall of the magnetic conduction inner cylinder; an outer throttling channel is formed between the outer wall of the bobbin and the inner wall of the damper shell; the inner throttling channel, the outer throttling channel and the magnetic conduction inner cylinder form a magnetorheological fluid flow channel, and the first through hole and the second through hole are used for communicating the magnetorheological fluid flow channel.
Compared with the prior art, the invention has the beneficial effects that:
1. the invention adopts a double-channel structure, reduces zero-field damping of the magnetorheological damper, and increases the maximum controllable damping force provided by the damper, thereby increasing the controllable damping force adjusting range of the magnetorheological damper on the premise of not increasing the volume and the weight of the magnetorheological damper;
2. according to the invention, the exciting coil, the throttling channel and the piston are separated, and the throttling channel is longer under the condition of the same axial length, so that a larger controllable damping force and a larger damping force adjusting range can be provided;
3. compared with the existing multi-channel magnetorheological damper, the invention has the advantages that only one exciting coil is arranged, and after the exciting coil is electrified, a magnetic field perpendicular to the flowing direction of magnetorheological fluid can be generated in both channels, so that the control is simple and convenient;
4. the invention can generate a magnetic field perpendicular to the flowing direction of the magnetorheological fluid in the whole throttling channel, thereby improving the utilization rate of the magnetic field and further improving the maximum controllable damping force and the damping force adjusting range of the magnetorheological damper.
Drawings
FIG. 1 is a schematic diagram of the structure of the present invention;
FIG. 2 is a cross-sectional view A-A of FIG. 1;
FIG. 3 is a schematic view of the structure of the positioning plate;
FIG. 4 is a schematic structural view of a bobbin;
FIG. 5 is a flow channel profile of the present invention;
fig. 6 is a magnetic field line distribution diagram of the present invention.
Detailed Description
The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are only some embodiments of the invention, but not all embodiments, and all other embodiments obtained by those skilled in the art without making creative efforts based on the embodiments of the present invention are all within the protection scope of the present invention.
A double-channel magnetorheological damper with a large adjustable range comprises an end cover I1, a damper shell 2, a positioning plate 3, an outer resistance magnetic strip 4, a bobbin 6, a piston rod 7, an inner resistance magnetic strip 11, a piston head 12, an excitation coil 13, a magnetic conduction inner cylinder 14 and an end cover II 15; the outer side of the piston rod 7 is sequentially and coaxially sleeved with a first end cover 1, a piston head 12 and a second end cover 15, a third sealing ring 9 is arranged between the first end cover 1 and the piston rod 7, and a fifth sealing ring 16 is arranged between the second end cover 15 and the piston rod 7; the piston head 12 and the piston rod 7 are connected through threads to form a piston; a damper shell 2 is fixedly arranged between the first end cover 1 and the second end cover 15 through bolts, and the damper shell 2 is coaxially sleeved on the outer side of the piston rod 7; a sealing ring IV 10 is arranged between the damper shell 2 and the end cover I1, and a sealing ring II 8 is arranged between the damper shell 2 and the end cover II 15; the outer side of the piston head 12 is coaxially sleeved with a magnetic conduction inner cylinder 14, and a first sealing ring 5 is arranged between the piston head 12 and the magnetic conduction inner cylinder 14; the outer side of the magnetic conduction inner cylinder 14 is coaxially sleeved with a bobbin 6, an excitation coil 13 is wound on the bobbin 6, an internal resistance magnetic strip 11 is arranged at the inner end of the bobbin 6, an external resistance magnetic strip 4 is arranged at the outer end of the bobbin 6, two ends of the bobbin 6 are respectively and fixedly connected with corresponding positioning plates 3 coaxially through screws, the outer end of each positioning plate 3 is connected with the inner wall of the damper shell 2, the inner end of each positioning plate 3 is connected with the outer wall of the magnetic conduction inner cylinder 14, two positioning plates 3 are coaxially sleeved on the outer side of a piston rod 7 in a ring mode, gaps are reserved between each positioning plate 3 and an adjacent end cover I1 or end cover II 15, and a plurality of through holes I17 penetrating the thickness direction of each positioning plate 3 are uniformly distributed along the respective circumferential direction and used for flowing magnetorheological fluid; the outer walls of the two ends of the magnetic conduction inner cylinder 14 are uniformly provided with a plurality of through holes II 18 penetrating the thickness direction of the magnetic conduction inner cylinder along the circumferential direction of the magnetic conduction inner cylinder, and an inner throttling channel is formed between the inner wall of the bobbin 6 and the outer wall of the magnetic conduction inner cylinder 14; an outer throttling channel is formed between the outer wall of the bobbin 6 and the inner wall of the damper housing 2; the inner throttling channel, the outer throttling channel and the magnetic conduction inner cylinder 14 form a magneto-rheological fluid flow channel, and the first through hole 17 and the second through hole 18 are used for communicating the magneto-rheological fluid flow channel. The piston divides the magnetic conduction inner cylinder 14 into two chambers, and the reciprocating motion of the piston drives magnetorheological fluid in the chambers to flow mutually through a through hole II 18 at two ends of the magnetic conduction inner cylinder 14, a through hole I17 defined as a plate and double throttling channels at the inner side and the outer side.
The inner wall of the bobbin 6 is uniformly provided with a plurality of inner winding bosses 20 along the circumferential direction of the bobbin 6, the outer wall of the bobbin 6 is uniformly provided with a plurality of outer winding bosses 19 along the circumferential direction of the bobbin, the outer winding bosses 19 are in one-to-one correspondence with the inner winding bosses 20, exciting coils 13 are wound on the outer winding bosses 19 and the inner winding bosses 20, an outer magnetic resistance strip 4 is arranged between every two adjacent outer winding bosses 19, an inner magnetic resistance strip 11 is arranged between every two adjacent inner winding bosses 20, the outer magnetic resistance strip 4 is arranged on the outer side of the corresponding exciting coil 13, and the inner magnetic resistance strip 11 is arranged on the inner side of the corresponding exciting coil 13; the external magnetic stripe 4 and the internal magnetic stripe 11 are used for sealing and formation of a magnetic circuit.
The winding directions of the exciting coils 13 on every two adjacent outer winding bosses 19 are opposite; the winding directions of the exciting coils 13 on every two adjacent inner winding bosses 20 are opposite.
The magnetic conduction inner cylinder 14, the winding tube 6 and the damper shell 2 are all made of magnetic conduction materials, and the rest parts except the magnetic conduction inner cylinder 14, the winding tube 6 and the damper shell 2 are all made of non-magnetic conduction materials.
The working principle of the invention is as follows:
the reciprocating motion of the piston drives magnetorheological fluid in the throttling channel to flow;
when the exciting coil is not electrified, no magnetic field exists in the throttling channel, and the reciprocating motion of the piston can form pressure difference at the two end surfaces of the piston, so that damping force is formed;
when the exciting coil is electrified, magnetic force lines start from the middle part of the winding tube to the inner side and the outer side of the winding tube; the part flowing to the inner side flows to the magnetic conduction inner pipe through the inner throttling channel, and flows back to the bobbin from the magnetic conduction inner pipe through the inner throttling channel; the part flowing to the outer side flows into the damper shell through the outer throttling channel, and then flows back to the bobbin from the damper shell through the outer throttling channel; the generated magnetic field occupies all the inner throttling channels and the outer throttling channels, and the direction of the magnetic field is perpendicular to the flowing direction of the magnetorheological fluid, so that the magnetorheological fluid influenced by the magnetic field generates a flux linkage which is the same as the direction of the magnetic field, the shearing strength is increased, and further, an additional damping force is formed; before the magnetic circuit is unsaturated, the intensity of the magnetic field in the throttling channel can be adjusted by changing the magnitude of the current in the exciting coil, so that the magnitude of the controllable damping force is changed, and the damping force of the magnetorheological damper is adjusted.
The invention can increase the rheological area under the limited volume and improve the maximum controllable damping force and the damping force adjusting range of the damper.
It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.
Furthermore, it should be understood that although the present disclosure describes embodiments, not every embodiment is provided with a separate embodiment, and that this description is provided for clarity only, and that the disclosure is not limited to the embodiments described in detail below, and that the embodiments described in the examples may be combined as appropriate to form other embodiments that will be apparent to those skilled in the art.
Claims (3)
1. A double-channel magnetorheological damper with a large adjustable range comprises an end cover I (1), a damper shell (2), a piston rod (7), a piston head (12) and an end cover II (15); the outer side of the piston rod (7) is sequentially coaxially sleeved with a first end cover (1), a piston head (12) and a second end cover (15), a damper shell (2) is fixedly arranged between the first end cover (1) and the second end cover (15), and the damper shell (2) is coaxially sleeved on the outer side of the piston rod (7) in a ring mode; the method is characterized in that: the magneto-rheological damper further comprises a positioning plate (3), an outer resistance magnetic strip (4), a winding tube (6), an inner resistance magnetic strip (11), an excitation coil (13) and a magnetic conduction inner cylinder (14); the magnetic conduction inner cylinder (14) is coaxially sleeved on the outer side of the piston head (12), the bobbin (6) is coaxially sleeved on the outer side of the magnetic conduction inner cylinder (14), the exciting coil (13) is wound on the bobbin (6), the inner end of the bobbin (6) is provided with the inner resistance magnetic strip (11), the outer end of the bobbin (6) is provided with the outer resistance magnetic strip (4), the two ends of the bobbin (6) are respectively and fixedly connected with the corresponding positioning plates (3) coaxially, the outer end of each positioning plate (3) is connected with the inner wall of the damper shell (2), the inner end of each positioning plate (3) is connected with the outer wall of the magnetic conduction inner cylinder (14), the two positioning plates (3) are coaxially sleeved on the outer side of the piston rod (7), a gap is reserved between each positioning plate (3) and the adjacent end cover I (1) or end cover II (15), the outer walls of the two ends of the bobbin (6) are respectively provided with a plurality of through holes I (17), and a plurality of inner cylinders II (18) are arranged on the outer walls of the two ends of the bobbin (14), and the inner walls of the bobbin (6) are connected with the outer wall of the outer wall (14) to form an inner channel of the magnetic conduction inner channel; an outer throttling channel is formed between the outer wall of the bobbin (6) and the inner wall of the damper housing (2); the inner throttling channel, the outer throttling channel and the magnetic conduction inner cylinder (14) form a magnetorheological fluid flow channel, and the first through hole (17) and the second through hole (18) are used for communicating the magnetorheological fluid flow channel; the inner wall of bobbin (6) is equipped with a plurality of interior wire winding boss (20), and the outer wall of bobbin (6) is equipped with a plurality of outer wire winding boss (19), a plurality of outer wire winding boss (19) set up with a plurality of interior wire winding boss (20) one-to-one, all twine exciting coil (13) on a plurality of outer wire winding boss (19) and a plurality of interior wire winding boss (20), all be equipped with between every adjacent two outer wire winding boss (19) and hinder magnetic stripe (4), all be equipped with internal resistance magnetic stripe (11) between every adjacent two interior wire winding boss (20), external resistance magnetic stripe (4) set up in the outside of exciting coil (13) that corresponds, internal resistance magnetic stripe (11) set up the inboard at exciting coil (13) that corresponds.
2. A dual channel magnetorheological damper having a large adjustable range according to claim 1, wherein: the winding directions of the exciting coils (13) on every two adjacent outer winding bosses (19) are opposite; the winding directions of the exciting coils (13) on every two adjacent inner winding bosses (20) are opposite.
3. A dual channel magnetorheological damper having a large adjustable range according to claim 2, wherein: the magnetic conduction inner cylinder (14), the winding tube (6) and the damper shell (2) are all made of magnetic conduction materials, and the rest parts except the magnetic conduction inner cylinder (14), the winding tube (6) and the damper shell (2) are all made of non-magnetic conduction materials.
Priority Applications (1)
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CN202210307472.6A CN114576301B (en) | 2022-03-25 | 2022-03-25 | Double-channel magnetorheological damper with large adjustable range |
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CN202210307472.6A CN114576301B (en) | 2022-03-25 | 2022-03-25 | Double-channel magnetorheological damper with large adjustable range |
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CN114576301B true CN114576301B (en) | 2024-01-30 |
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Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH07332427A (en) * | 1994-06-06 | 1995-12-22 | Natl Res Inst For Metals | Variable damping force shock absorber and magnetic fluid flow control mechanism suitable thereto |
JP2001165229A (en) * | 1999-12-08 | 2001-06-19 | Sanwa Tekki Corp | Magnetic viscous fluid flow type damping device |
JP2008224001A (en) * | 2007-03-15 | 2008-09-25 | Honda Motor Co Ltd | Variable damping force damper |
WO2013059951A1 (en) * | 2011-10-27 | 2013-05-02 | Pontificia Universidad Catolica De Chile | Magnetorheological damper |
CN110836236A (en) * | 2019-11-26 | 2020-02-25 | 重庆大学 | Rotary magnetorheological damper capable of outputting asymmetric damping |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20120292143A1 (en) * | 2005-06-21 | 2012-11-22 | Eric Anderfaas | Magnetorheological Damper With Annular Valve |
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2022
- 2022-03-25 CN CN202210307472.6A patent/CN114576301B/en active Active
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH07332427A (en) * | 1994-06-06 | 1995-12-22 | Natl Res Inst For Metals | Variable damping force shock absorber and magnetic fluid flow control mechanism suitable thereto |
JP2001165229A (en) * | 1999-12-08 | 2001-06-19 | Sanwa Tekki Corp | Magnetic viscous fluid flow type damping device |
JP2008224001A (en) * | 2007-03-15 | 2008-09-25 | Honda Motor Co Ltd | Variable damping force damper |
WO2013059951A1 (en) * | 2011-10-27 | 2013-05-02 | Pontificia Universidad Catolica De Chile | Magnetorheological damper |
CN110836236A (en) * | 2019-11-26 | 2020-02-25 | 重庆大学 | Rotary magnetorheological damper capable of outputting asymmetric damping |
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