阅读说明：本技术 一种对称多筒旋转式磁流变阻尼器 (Symmetrical multi-cylinder rotary magnetorheological damper ) 是由 李会军 欧阳云霞 宋爱国 陈大鹏 于 2019-11-07 设计创作，主要内容包括：本发明提供了一种对称多筒旋转式磁流变阻尼器,包括：外壳、分别设置在外壳顶部和底部的上下封盖、以及设置在外壳内的旋转轴,定子,内外动筒,静筒,线圈支架,线圈和间隔环。本发明设计的阻尼器剖面为轴对称截面,单侧为T型截面,在传统的单筒旋转式阻尼器的结构基础上,优化为对称多筒旋转式阻尼器。此结构在阻尼器内一共形成八条流体间隙,增加了流体间隙数量,远远多于传统的阻尼器,实验证明,能够大大增加切割磁流变液的有效面积,提高了扭矩-体积比,减小了转动惯量,满足一些需要大阻尼,小体积,低功耗的应用场合。(The invention provides a symmetrical multi-cylinder rotary magnetorheological damper, which comprises: the shell, set up upper and lower closing cap and the rotation axis that sets up in the shell, stator, interior outer movable cylinder, quiet section of thick bamboo, coil support, coil and spacer ring in shell top and bottom respectively. The section of the damper designed by the invention is an axisymmetric section, and a single side is a T-shaped section, so that the damper is optimized to be a symmetric multi-cylinder rotary damper on the basis of the structure of the traditional single-cylinder rotary damper. The structure forms eight fluid gaps in the damper, increases the quantity of the fluid gaps, is far more than that of the traditional damper, and experiments prove that the effective area for cutting the magnetorheological fluid can be greatly increased, the torque-volume ratio is improved, the rotational inertia is reduced, and the application occasions requiring large damping, small volume and low power consumption are met.)

1. A symmetrical multi-cylinder rotary magnetorheological damper, comprising: the device comprises a shell, an upper sealing cover, a lower sealing cover, a rotating shaft, a stator, an inner movable cylinder, an outer movable cylinder, a fixed cylinder, a coil bracket, a coil and a spacing ring, wherein the upper sealing cover and the lower sealing cover are respectively arranged at the top and the bottom of the shell; the section of the rotating shaft is cross-shaped, the transverse direction of the rotating shaft is a radial transmission shaft, the longitudinal direction of the rotating shaft is an axial transmission shaft, and the top and the bottom of the axial transmission shaft respectively penetrate through the upper sealing cover and the lower sealing cover; the stator comprises an upper stator arranged above the radial transmission shaft and a lower stator arranged below the radial transmission shaft, and the upper stator and the lower stator are respectively fixedly connected with the upper sealing cover and the lower sealing cover; the inner and outer movable cylinders comprise an upper inner movable cylinder and an upper outer movable cylinder which are fixed on the upper half part of the rotating shaft, and a lower inner movable cylinder and a lower outer movable cylinder which are fixed on the lower half part of the rotating shaft; the coil support comprises an upper coil support arranged above the upper inner moving cylinder and a lower coil support arranged below the lower inner moving cylinder, the upper coil and the lower coil are respectively wound on the upper coil support and the lower coil support, and the spacing ring comprises an upper spacing ring arranged between the upper coil and the upper outer moving cylinder and a lower spacing ring arranged between the lower coil and the lower outer moving cylinder; the upper and lower static cylinders, the upper and lower coil brackets, the upper and lower spacing rings are respectively fixedly connected with the upper stator and the lower stator; two fluid gaps are formed between the upper inner and upper outer moving cylinders and the upper static cylinder, two fluid gaps are formed between the upper inner and upper outer moving cylinders and the upper stator and the shell, two fluid gaps are formed between the lower inner and lower outer moving cylinders and the lower static cylinder, two fluid gaps are formed between the lower inner and lower outer moving cylinders and the lower stator and the shell, eight fluid gaps are formed in total, and the eight fluid gaps are filled with magnetorheological fluid.

2. The symmetric multi-cylinder rotary magnetorheological damper of claim 1, wherein: gaps are reserved among the upper stator, the lower stator and the radial transmission shaft of the rotating shaft, and magnetorheological fluid is filled in the gaps.

3. The symmetric multi-cylinder rotary magnetorheological damper of claim 1, wherein: and the inner sides of the upper stator and the lower stator are provided with a plane bearing and a framework oil seal, and the plane bearing and the framework oil seal are sleeved outside the rotating shaft.

4. The symmetric multi-cylinder rotary magnetorheological damper of claim 1, wherein: the transmission shaft is provided with two circular grooves in the front and the back respectively, an upper internal moving cylinder, a lower internal moving cylinder, an upper external moving cylinder and a lower external moving cylinder are arranged in the circular grooves.

5. The symmetric multi-cylinder rotary magnetorheological damper of claim 1, wherein: two circular through holes which are symmetrical up and down are formed in the shell, and the circular through holes are communicated with the eight fluid gaps to form a liquid supply channel.

6. The symmetric multi-cylinder rotary magnetorheological damper of claim 1, wherein: the inner and outer movable cylinders are fixed on the rotating shaft through machine screws, the upper and lower stationary cylinders, the upper and lower coil supports, the upper and lower spacing rings are respectively fixedly connected with the upper and lower stators through machine screws, and the upper and lower sealing covers are fixedly connected with the upper and lower stators through round head screws.

Technical Field

The invention belongs to the technical field of dampers, relates to a damper for generating damping torque by adopting magnetorheological fluid, and particularly relates to a symmetrical multi-cylinder rotary type magnetorheological damper.

Background

The rheological effect of the magnetorheological fluid enables the state of the magnetorheological fluid to be rapidly converted from a liquid state to a solid-like state under the action of an external magnetic field, and the magnetorheological fluid has certain shear resistance, and at the moment, damping force is output outwards, depends on the magnetic field intensity and can be instantly, continuously and reversely changed. Based on the magneto-rheological fluid, the magneto-rheological damper becomes a novel semi-active actuator with excellent characteristics of inherent passivity, quick response time, high torque-volume ratio and low power requirement.

The magneto-rheological dampers in different structural forms are suitable for different application occasions, the existing magneto-rheological damper structures are divided into a direct-acting type and a rotary type, and in some occasions, such as a rehabilitation robot, a flexible joint robot needs the magneto-rheological damper to output a continuously rotatable damping torque, so that the research on the rotary type magneto-rheological damper is of practical significance.

The difficulty in designing the magnetorheological damper is that on the premise of ensuring the small size of the damper, the magnetorheological damper still can output a damping torque large enough.

The cylindrical rotary magnetorheological damper has the advantages of simple structure and easiness in processing and assembling, but the torque-volume ratio of the cylindrical rotary magnetorheological damper is very small, and a multi-cylinder magnetorheological damper has been researched and made, so that the size of the damper is reduced while large output torque is obtained. However, the existing multi-cylinder damper does not fully utilize the assembled volume, neglects the influence of axial pressure and friction force on the initial damping, and has incomplete liquid leakage prevention measures.

Disclosure of Invention

In order to solve the problems and obtain a larger torque-volume ratio, the symmetrical multi-cylinder rotary magnetorheological damper is designed on the basis of not increasing the assembly difficulty, the structure greatly increases the number of channels of the damper fluid gap, and the output damping torque is increased.

In order to achieve the purpose, the invention provides the following technical scheme:

a symmetrical multi-barrel rotary magnetorheological damper comprising: the device comprises a shell, an upper sealing cover, a lower sealing cover, a rotating shaft, a stator, an inner movable cylinder, an outer movable cylinder, a fixed cylinder, a coil bracket, a coil and a spacing ring, wherein the upper sealing cover and the lower sealing cover are respectively arranged at the top and the bottom of the shell; the section of the rotating shaft is cross-shaped, the transverse direction of the rotating shaft is a radial transmission shaft, the longitudinal direction of the rotating shaft is an axial transmission shaft, and the top and the bottom of the axial transmission shaft respectively penetrate through the upper sealing cover and the lower sealing cover; the stator comprises an upper stator arranged above the radial transmission shaft and a lower stator arranged below the radial transmission shaft, and the upper stator and the lower stator are respectively fixedly connected with the upper sealing cover and the lower sealing cover; the inner and outer movable cylinders comprise an upper inner movable cylinder and an upper outer movable cylinder which are fixed on the upper half part of the rotating shaft, and a lower inner movable cylinder and a lower outer movable cylinder which are fixed on the lower half part of the rotating shaft; the coil support comprises an upper coil support arranged above the upper inner moving cylinder and a lower coil support arranged below the lower inner moving cylinder, the upper coil and the lower coil are respectively wound on the upper coil support and the lower coil support, and the spacing ring comprises an upper spacing ring arranged between the upper coil and the upper outer moving cylinder and a lower spacing ring arranged between the lower coil and the lower outer moving cylinder; the upper and lower static cylinders, the upper and lower coil brackets, the upper and lower spacing rings are respectively fixedly connected with the upper stator and the lower stator; two fluid gaps are formed between the upper inner and upper outer moving cylinders and the upper static cylinder, two fluid gaps are formed between the upper inner and upper outer moving cylinders and the upper stator and the shell, two fluid gaps are formed between the lower inner and lower outer moving cylinders and the lower static cylinder, two fluid gaps are formed between the lower inner and lower outer moving cylinders and the lower stator and the shell, eight fluid gaps are formed in total, and the eight fluid gaps are filled with magnetorheological fluid.

Furthermore, large gaps are formed among the upper stator, the lower stator and the radial transmission shaft of the rotating shaft, and magnetorheological fluid is filled in the gaps.

Further, the inner sides of the upper stator and the lower stator are provided with a plane bearing and a framework oil seal, and the plane bearing and the framework oil seal are sleeved outside the rotating shaft.

Furthermore, the front and the back of the transmission shaft are respectively provided with two circular grooves, an upper internal moving cylinder, a lower internal moving cylinder, an upper external moving cylinder and a lower external moving cylinder which are arranged in the circular grooves.

Furthermore, two circular through holes which are symmetrical up and down are formed in the shell, and the circular through holes are communicated with the eight fluid gaps to form a liquid supply channel.

Furthermore, the inner and outer movable cylinders are fixed on the rotating shaft through machine screws, the upper and lower stationary cylinders, the upper and lower coil supports, the upper and lower spacing rings are respectively fixedly connected with the upper and lower stators through machine screws, and the upper and lower sealing covers are fixedly connected with the upper and lower stators through round head screws.

Compared with the prior art, the invention has the following advantages and beneficial effects:

1. the section of the damper designed by the invention is an axisymmetric section, and a single side is a T-shaped section, so that the damper is optimized to be a symmetric multi-cylinder rotary damper on the basis of the structure of the traditional single-cylinder rotary damper. The structure forms eight fluid gaps in the damper, increases the quantity of the fluid gaps, is far more than that of the traditional damper, and experiments prove that the effective area for cutting the magnetorheological fluid can be greatly increased, the torque-volume ratio is improved, the rotational inertia is reduced, and the application occasions requiring large damping, small volume and low power consumption are met.

2. Two coils of the symmetrical multi-cylinder rotary magnetorheological damper can work independently, generated magnetic lines of force are not interfered with each other, the same external electric field is applied, the damper can output full damping force and half damping force, and the requirements of different occasions are met.

3. The plane bearing greatly reduces the influence of axial pressure and friction force on the initial damping force.

4. Gaps of magnetorheological fluid are filled between the upper stator and the lower stator and the rotating shaft, so that the contact area between the rotating shaft and the fixing piece is reduced, and the initial damping is reduced.

5. The framework oil seal reduces the liquid leakage phenomenon.

Drawings

Fig. 1 is a schematic structural view of a symmetrical multi-cylinder rotary magnetorheological damper provided by the invention, wherein (a) is an overall view, and (b) is a schematic sectional view in the direction of a-a of (a).

FIG. 2 is a fluid gap profile in the damper.

Fig. 3 is a schematic diagram of injection hole channels in the damper.

FIG. 4 is a diagram of a magnetic field line distribution for a finite element analysis.

FIG. 5 is a diagram of a magnetic field strength profile for a finite element analysis.

Fig. 6 is a detailed magnetic field strength profile for path a-B.

FIG. 7 is a detailed magnetic field profile for paths C-D.

Description of reference numerals:

1-rotating shaft, 2-upper inner moving cylinder, 3-lower inner moving cylinder, 4-upper outer moving cylinder, 5-lower outer moving cylinder, 6-upper stationary cylinder, 7-lower stationary cylinder, 8-upper coil support, 9-lower coil support, 10-upper spacing ring, 11-lower spacing ring, 12-upper stator, 13-lower stator, 14-upper sealing cover, 15-lower sealing cover, 16-shell, 17-plane bearing, 18-framework oil seal, 19-upper coil, 20-lower coil, 21-first fluid gap, 22-second fluid gap, 23-third fluid gap, and 24-fourth fluid gap.

Detailed Description

The technical solutions provided by the present invention will be described in detail below with reference to specific examples, and it should be understood that the following specific embodiments are only illustrative of the present invention and are not intended to limit the scope of the present invention.

The invention provides a symmetrical multi-cylinder rotary magnetorheological damper which mainly comprises a rotating shaft, a stator, an internal and external moving cylinder, a static cylinder, a coil bracket, a spacing ring, an upper sealing cover, a lower sealing cover and a shell. The two internal moving cylinders and the two external moving cylinders are fixed on the rotating shaft through machine screws to form a vertically symmetrical rotating mechanism; the two stator cylinders and the two coil brackets are respectively fixed on the two stators through machine screws, the coils are wound on the coil brackets, and the two stators are fixed with the upper and lower sealing covers through common round head screws to form a whole fixing piece; the rotating mechanism is arranged in the fixing piece through the plane bearing and the oil seal, so that the rotating mechanism cannot move up and down when being subjected to axial force, and the influence of axial friction force is reduced. After an external electric field is applied, magnetic force lines generated by the coils vertically pass through 8 fluid gaps filled with magnetorheological fluid, the mutual movement of the static cylinder and the inner and outer movable cylinders is blocked by shearing force generated by the rheological effect of the magnetorheological fluid, the output shaft of the rotating shaft is a D-shaped tangent plane shaft, and the rotating shaft is connected with the gear through the output shaft to output damping force outwards. The damping force is instantaneously changed along with the change of the impressed current, and the controllability is realized.

Specifically, as shown in fig. 1, the symmetrical multi-cylinder rotary magnetorheological damper comprises a rotating shaft 1, an upper inner moving cylinder 2, a lower inner moving cylinder 3, an upper outer moving cylinder 4, a lower outer moving cylinder 5, an upper stationary cylinder 6, a lower stationary cylinder 7, an upper coil support 8, a lower coil support 9, an upper spacing ring 10, a lower spacing ring 11, an upper sealing cover 14 and a lower sealing cover 15.

An upper cover 14 and a lower cover 15 are respectively positioned at the top and bottom of the damper. The section of the rotating shaft 1 is cross-shaped, the rotating shaft is a radial transmission shaft in the transverse direction and an axial transmission shaft in the longitudinal direction, the rotating shaft 1 is arranged in the damper in the longitudinal direction integrally, and the top and the bottom of the axial transmission shaft respectively penetrate through the upper sealing cover and the lower sealing cover. The periphery of the rotating shaft is sleeved with two sets of plane bearings 17 and framework oil seals 18, and the rotating shaft 1 is arranged in the fixed cylinder body structure through the plane bearings 17 and the framework oil seals 18, so that the rotating shaft is guaranteed not to move up and down when being subjected to axial force, and the influence of tangential friction is reduced. The upper stator 12 is arranged above the radial transmission shaft of the rotating shaft 1, the lower stator 13 is arranged below the radial transmission shaft of the rotating shaft 1, the upper sealing cover 14 and the lower sealing cover 15 are respectively fixed with the upper stator 12 and the lower stator 13 through 6 screws, so that the upper sealing cover and the lower sealing cover can be tightly matched, magnetic lines of force can smoothly pass through a magnetic circuit and simultaneously prevent liquid leakage, and when the rotating shaft is ensured to rotate, the static cylinder can keep relatively static with the shell to form a fixing piece. Go up stator 12, the inboard processing of lower stator 13 has circular recess, flat bearing and skeleton oil blanket are arranged in the recess, the stator, upper and lower closing cap, flat bearing and rotation axis clearance fit, the radial transmission shaft of stator and rotation axis is gapped, reduce the area of contact of rotation axis and mounting, reduce initial damping, skeleton oil blanket and rotation axis transition fit, the diameter of circular recess slightly is less than the diameter of skeleton oil blanket simultaneously, when the assembly, the skeleton oil blanket receives axial and radial extrusion, prevent that magnetorheological suspensions from revealing. The framework oil seal 18 is used for replacing the traditional O-shaped ring, so that the liquid leakage condition generated when the rotating shaft rotates is greatly relieved. When shell and closing cap during the close fit, the inside axial pressure of casing can increase, and back on using rotation axis 1 can lead to initial damping to be fairly big, and the plane bearing can reduce the axial pressure greatly and to the influence of output damping, consequently can guarantee that the radial transmission shaft of rotation axis can not reciprocate when receiving upper and lower pressure, and reduce the influence of axial friction power.

Two circular grooves are respectively cut in the front and the back of a radial transmission shaft of a rotating shaft 1, an upper inner movable cylinder, a lower inner movable cylinder and an upper outer movable cylinder are arranged in the circular grooves and fixed on the rotating shaft through a machine-meter screw, the rotating shaft is driven to rotate when rotating, and the inner and outer movable cylinders cut the magnetorheological fluid. The upper inner and outer moving cylinders are positioned outside the upper stator, and the lower inner and outer moving cylinders are positioned outside the lower stator. The upper static cylinder 6 is arranged between the upper inner movable cylinder and the upper outer movable cylinder, and the lower static cylinder 7 is arranged between the lower inner movable cylinder and the lower outer movable cylinder. The upper coil support 8 is arranged above the upper inner moving cylinder, the lower coil support 9 is arranged below the lower inner moving cylinder, the upper coil 19 and the lower coil 20 are respectively wound on the upper coil support 8 and the lower coil support 9, and two through holes are formed in the side surface of the shell and used as wire outlet holes. The upper spacer ring 10 is disposed between the upper coil 19 and the upper outer rotor, and the lower spacer ring 11 is disposed between the lower coil 20 and the lower outer rotor. The upper static cylinder 6, the lower static cylinder 7, the upper coil support 8, the lower coil support 9, the upper spacing ring 10 and the lower spacing ring 11 are respectively fixed on the upper stator 12 and the lower stator 13 through machine screws, so that when the rotating shaft 1 rotates, the static cylinder and the shell 16 can keep relatively static to form a fixing piece.

FIG. 2 is a top half of a fluid gap profile of the present invention, the bottom half being identical. As can be seen from the figure, two fluid gaps are formed among the upper inner moving cylinder 2, the upper outer moving cylinder 4 and the upper static cylinder 6, two fluid gaps are formed among the upper inner moving cylinder 2, the upper outer moving cylinder 4, the upper stator 12 and the shell 16, and the upper half part has four fluid gaps — a first fluid gap 21, a second fluid gap 22, a third fluid gap 23 and a fourth fluid gap 24; similarly, two fluid gaps are formed between the lower inner and outer moving cylinders and the lower static cylinder, two fluid gaps are formed between the lower inner and outer moving cylinders, the lower stator and the outer shell, and eight fluid gaps are formed in the whole magnetorheological damper.

Fig. 3 is a diagram of an injection hole channel of the present invention, two circular threaded holes are formed at the housing, the circular threaded holes are symmetrical up and down, ∩ -shaped through holes are formed at the concentric axes of the circular through holes by the two spacing rings, the two stationary cylinders and the two coil supports, a liquid supply channel is formed, and a user can use a small injector to inject liquid into the eight fluid gaps through the injection channel until the eight fluid gaps are filled with magnetorheological fluid.

Gaps are reserved between the upper stator 12 and the lower stator 13 and the rotating shaft 1, and magnetorheological fluid is filled in the gaps, so that the contact area between the rotating shaft 1 and the fixing piece is reduced, and initial damping is reduced.

The upper and lower coils 19 and 20 are wound around the upper and lower coil supports 8 and 9, respectively, below the upper and lower covers 14 and 15, and are also placed near the fluid gap to maximize the active shear area and minimize reluctance. When external current is applied to the upper coil 19 and the lower coil 20, magnetic flux generated by the coils first passes vertically through the fluid gap, then flows into the housing, then into the cover, and finally into the stator, forming a closed magnetic circuit. The magnetic field lines in the magnetic circuit are plotted in fig. 3, and it is evident that the magnetic field lines are almost entirely concentrated in the intended closed magnetic circuit, indicating that the magnetic circuit design is in principle completely correct. And the magnetic lines of force distribution of the upper half part and the lower half part of the magnetic circuit are symmetrical and do not interfere with each other, and the magnetic lines of force can fully and vertically pass through the eight fluid gaps. It is stated that the two coils may operate independently or in concert. The user can realize the independent work or the joint work of the upper part and the lower part of the symmetrical multi-cylinder rotary damper, and can output full damping force and semi-damping force, thereby meeting the requirements of different occasions.

FIG. 4 is a magnetic induction distribution plot of the finite element analysis results of the present invention, wherein the magnetic induction is detailed for paths A-B in FIG. 4 as shown in FIG. 5, and the magnetic induction is detailed for paths C-D as shown in FIG. 6. The excitation given by the invention is 260 ampere turns of each coil, the magnetic induction intensity of the magnetorheological fluid in the working gap is about 0.7T, the magnetic induction intensity of the dynamic damping disk, the static damping disk and the shell is about 1.6T, all parts of the closed magnetic circuit can simultaneously achieve magnetic saturation, and the design of the structural parameters of all parts of the magnetorheological damper is reasonable.

The screws used in the shell are machine-meter screws, so that the difficulty in assembly and the waste of materials and space caused by assembly are reduced. The magnetic conductive material selected when the magnetorheological damper is designed meets the characteristics of high magnetic conductivity, high saturation magnetic induction, stable magnetism and no magnetic aging. The magnetic conductive material selected by the invention is soft magnetic material electric pure iron DT4C, and when the external magnetic field intensity reaches 1.6T, DT4C reaches magnetic saturation.

The performance of the selected magnetorheological fluid in the design of the magnetorheological damper meets the following requirements at the same time:

(1) should have a very pronounced rheological effect;

(2) should respond immediately and reversibly to changes in the magnetic field;

(3) a wide range of controllability should be allowed;

(4) should provide high resistance to hard settling, be readily redispersible;

the magnetorheological fluid adopts MRF-122EG produced by Lord company in America, can simultaneously meet the requirements, and can reach magnetic saturation when the external magnetic field intensity reaches 0.7T.

The working principle of the invention is as follows:

the magnetorheological fluid damper is a semi-active actuator made based on the rheological effect of the magnetorheological fluid, and the rheological effect of the magnetorheological fluid means that the magnetorheological fluid has the characteristics similar to Newtonian fluid when no external magnetic field exists. When an external magnetic field exists, the state of the magnetorheological fluid can be rapidly converted from a liquid state to a quasi-solid state, and the magnetorheological fluid has certain shear resistance; when the external magnetic field is removed, the state of the magnetorheological fluid is restored to be liquid, and the conversion is finished in millisecond-scale time. The fluid is usually confined between two magnetic poles, under the condition of no magnetic field, the magnetorheological suspension particles are uniformly distributed in the carrier fluid, and the suspension body is represented as Newtonian fluid; when a magnetic field is applied, the particles are magnetized and subjected to magnetic forces, so that they form a chain-like structure or aggregate, substantially parallel to the direction of the magnetic field, which creates a shear resistance against the two poles of relative motion or fluid flow.

When current is applied to the coil from the outside, the magnetorheological fluid in the fluid gap has certain anti-shearing capacity, the movement of the inner movable cylinder and the outer movable cylinder is blocked, the movement of the rotating shaft is blocked, and the damping force is output outwards and is increased along with the increase of the current until the magnetorheological fluid reaches magnetic saturation, and the controllability is strong.

The technical means disclosed in the invention scheme are not limited to the technical means disclosed in the above embodiments, but also include the technical scheme formed by any combination of the above technical features. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of the present invention, and such improvements and modifications are also considered to be within the scope of the present invention.