CN219101931U

CN219101931U - Oil magnetofluid damper

Info

Publication number: CN219101931U
Application number: CN202320526527.2U
Authority: CN
Inventors: 王悦新; 黄亮; 刘毅萍; 卢玮
Original assignee: Longyan University
Current assignee: Longyan University
Priority date: 2023-03-17
Filing date: 2023-03-17
Publication date: 2023-05-30
Anticipated expiration: 2033-03-17

Abstract

The utility model discloses an oil magnetofluid damper which comprises a cylinder body, a floating separation piston and a piston rod, wherein a magnetic flow slide valve piston mechanism is connected in an oil cavity in a sliding way, and the lower end of the piston rod extends into the cylinder body from a top end cover and is fixedly connected with the magnetic flow slide valve piston mechanism. The magnetic flow slide valve piston mechanism comprises a magnetic flow piston, a piston seat body, a slide valve core, an excitation coil and a piston outer body. The oil magnetofluid damper can change the damping of the damper without replacing hydraulic oil, and is mainly beneficial to the internal magnetic flow slide valve piston mechanism. Compared with those magneto-rheological fluid dampers replacing hydraulic oil, the magneto-rheological fluid damper can well improve the defects of the traditional magneto-rheological fluid damper, simultaneously greatly reduce the uncontrollable factors of the adjustment damping, and has relatively simple control due to a small amount of magneto-rheological fluid in the spool of the spool valve; compared with the prior damper with the whole damper filled with magnetorheological fluid, the novel damper has smaller exciting current and more flexible reaction.

Description

Oil magnetofluid damper

Technical Field

The utility model relates to the technical field of dampers, in particular to an oil magnetofluid damper.

Background

The principle of the shock absorber carried in the automobile suspension system on the market is that when a piston reciprocates in a cylinder barrel of the shock absorber, oil in the cylinder continuously shuttles back and forth between the piston and each valve, and further rubs against the inner wall and the inner friction between liquid molecules to generate damping force for vibration, and the friction and the damping are mainly relied on in the process to absorb and convert the energy of impact. The damping generated by the shock absorber taking hydraulic oil as damping medium is uncontrollable, passengers need to respond to the 'soft' and 'hard' degree of an automobile suspension system in time according to different driving working conditions and road conditions if the passengers want to obtain more comfortable riding environment, and therefore the shock absorber with variable damping, namely the magneto-rheological damper, is arranged. The biggest difference with the traditional hydraulic damper is that the damping medium of the magnetorheological fluid damper is replaced by hydraulic oil and an electromagnetic system is added. The simplified schematic diagram of the existing magnetorheological fluid damper is shown in fig. 1, and the working principle of the magnetorheological damper is that when the current in the exciting coil 02 increases, the magnetic field in the orifice is enhanced, the resistance of the magnetorheological fluid 03 flowing through the orifice is increased, so that the damping force output by the damper is increased, and otherwise, the current is reduced, and the damping force is also reduced. The magnitude of the damping force of the damper can be controlled by adjusting the input current. The suspension damping self-adaptive road condition can be changed by combining a running system of the vehicle to achieve the optimal damping effect. In summary, it is readily apparent that the lubricity of magnetorheological fluids is inferior to that of hydraulic oils, which results in a large flow resistance to itself, which tends to adversely affect the life of the valves, seals, and relatively rubbed components; meanwhile, the magnetic field of the exciting coil cannot be completely restrained between the piston 01 and the orifice, so that the magnetorheological fluid outside the piston 01 has solidification phenomena with different degrees, and the damping linearity of the shock absorber is poor, namely, uncontrollable factors of the external magnetorheological fluid are too many; the magnetic particles in the magnetorheological fluid filled in the cylinder can be deposited even solidified under the long-time static condition, so that the damping effect of the damper is greatly reduced.

Disclosure of Invention

In order to overcome the defects in the prior art, the utility model aims to provide the oil magnetofluid damper which is relatively simple to control and flexible in reaction.

In order to achieve the above purpose, the present utility model adopts the following technical scheme:

the oil magnetofluid damper comprises a cylinder body, a floating separation piston and a piston rod, wherein a bottom end cover and a top end cover are respectively fixed at the bottom and the top of the cylinder body, the floating separation piston is sleeved in the cylinder body in a sliding manner, the space between the floating separation piston and the bottom end cover in the cylinder body is an air chamber and stores air with certain pressure, and the space between the floating separation piston and the top end cover in the cylinder is an oil chamber for filling hydraulic oil;

the lower end of the piston rod extends into the cylinder body from the top end cover and is fixedly connected with the magnetic flow slide valve piston mechanism;

the magnetic flow slide valve piston mechanism comprises a magnetic flow piston, a piston seat body, a slide valve core, an excitation coil and a piston outer body;

the piston outer body is connected to the inside of the cylinder body in a sliding manner, the piston seat body is fixedly connected to the inside of the piston outer body, the exciting coil is fixedly connected to the annular groove in the outer circular wall of the piston seat body, the two shaft ends of the piston seat body are respectively fixed with a piston end cover, and the two piston end covers are respectively provided with a hollowed-out hole for hydraulic oil to pass through;

the slide valve core is in sliding sleeve connection with an inner hole of the piston seat body, a plurality of annular plates are axially arranged on the outer circumferential wall of the slide valve core at intervals, a plurality of flow holes are respectively arranged on the annular plates at intervals along the circumferential direction, two annular groove-shaped valve ports are axially arranged on the inner hole of the piston seat body at intervals, a plurality of flow passages are respectively arranged on the two shaft end surfaces of the piston seat body at intervals along the circumferential direction, the flow passages at the two shaft ends are respectively communicated with the valve ports at the corresponding sides, and the opening of the valve ports can be changed when the slide valve core moves along the axial direction;

sealing end covers are respectively fixed at two shaft ends of the spool valve core of the spool valve, and magnetorheological fluid is filled in the spool valve core of the spool valve;

the middle part of the magnetic flow piston is provided with an annular part, a plurality of orifices are arranged on the peripheral wall of the annular part at intervals along the circumferential direction, the magnetic flow piston is in sliding sleeve joint with the sealing end covers at the two shaft ends of the spool valve, and the annular part of the magnetic flow piston is positioned in the spool valve; the two ends of the magnetic flow piston are respectively fixed with baffle rings, and a reset spring sleeved on the magnetic flow piston is connected between the baffle rings at the two ends and the sealing end covers at the corresponding sides; the two ends of the magnetic flow piston are respectively and slidably sleeved with a compressing seat, the compressing seat at one end is sleeved at the end part of the piston rod, the compressing seat at the other end is sleeved in the piston end cover at the corresponding side, and a safety spring sleeved on the magnetic flow piston is respectively connected between the two compressing seats and the baffle ring at the corresponding side.

Further, the outer ring of the outer piston body is provided with a combined sealing ring, and the combined sealing ring is used for dynamic sealing in the process that the outer piston body slides along the inner part of the cylinder body.

Further, the seal end cover is provided with a Gelai ring sleeved on the magnetic flow piston.

Further, the sealing end covers at the two shaft ends of the magnetic flow piston are respectively fixed with a push cover, and the push covers are in propping connection with the corresponding reset springs.

Further, an adjusting screw is connected to the end cover of the piston far away from one end of the piston rod in a threaded manner, and the end part of the adjusting screw is propped against the corresponding pressing seat.

By adopting the technical scheme, the method has the following beneficial technical effects: the oil magnetofluid damper can change the damping of the damper without replacing hydraulic oil, and is mainly beneficial to the internal magnetic flow slide valve piston mechanism. Compared with those magneto-rheological fluid dampers replacing hydraulic oil, the magneto-rheological fluid damper can well improve the defects of the traditional magneto-rheological fluid damper, simultaneously greatly reduce the uncontrollable factors of the adjustment damping, and has relatively simple control due to a small amount of magneto-rheological fluid in the spool of the spool valve; compared with the method that the whole damper cylinder is filled with magnetorheological fluid, the novel damper has smaller exciting current and more flexible reaction; the components of conventional dampers, whether they are on a magnetorheological spool piston mechanism or on an end cap seal, can be used in common, as the damping medium is still hydraulic oil, which also gives better linear damping.

Drawings

The utility model is described in further detail below with reference to the drawings and detailed description;

FIG. 1 is a simplified schematic diagram of a prior art magnetorheological fluid damper;

FIG. 2 is a cross-sectional view of an oil magnetofluid damper of the present utility model;

FIG. 3 is a cross-sectional view of a magnetic flow spool valve piston mechanism;

FIG. 4 is a schematic view of a piston housing;

FIG. 5 is a schematic illustration of a spool valve;

FIG. 6 is a schematic illustration of oil flow between a piston housing and a spool valve cartridge.

Description of the embodiments

As shown in fig. 2-6, the oil magnetofluid damper comprises a cylinder body 1, a floating separation piston 2 and a piston rod 3, wherein a bottom end cover 4 and a top end cover 5 are respectively fixed at the bottom and the top of the cylinder body 1, the floating separation piston 2 is sleeved in the cylinder body 1 in a sliding manner, the space between the floating separation piston 2 and the bottom end cover 4 in the cylinder body 1 is an air chamber and stores air with certain pressure, and the space between the floating separation piston 2 and the top end cover 5 in the cylinder is an oil chamber for filling hydraulic oil;

the oil chamber is slidably connected with a magnetic flow slide valve piston mechanism 6, the lower end of a piston rod 3 extends into the cylinder body 1 from a top end cover 5 and is fixedly connected with the magnetic flow slide valve piston mechanism 6, and the magnetic flow slide valve piston mechanism 6 divides the oil chamber into an upper chamber (with a rod chamber) and a lower chamber (without a rod chamber); in the process of up-and-down vibration of the magnetic flow slide valve piston mechanism 6, a certain volume difference exists between the upper chamber and the lower chamber due to the existence of the piston rod 3, and the volume difference is mainly compensated and eliminated by up-and-down movement of the compression air cavity of the floating separation piston 2.

The magnetic flow slide valve piston mechanism 6 comprises a magnetic flow piston 61, a piston seat body 62, a slide valve core 63, an excitation coil 64 and a piston outer body 65;

the outer piston body 65 is slidably connected inside the cylinder 1, a combined sealing ring 6501 is arranged on the outer ring of the outer piston body 65, and the combined sealing ring 6501 is used for dynamic sealing in the process that the outer piston body 65 slides along the inside of the cylinder 1. The piston seat body 62 is fixedly connected inside the piston outer body 65, the exciting coil 64 is fixedly connected in an annular groove on the outer circular wall of the piston seat body 62, two shaft ends of the piston seat body 62 are respectively fixed with a piston end cover 66, and the two piston end covers 66 are respectively provided with a hollowed-out hole for hydraulic oil to pass through;

the spool 63 is slidably engaged with the inner hole of the piston seat 62, a plurality of annular plates 6301 are axially provided on the outer circumferential wall of the spool 63 at intervals, and a plurality of flow holes 6302 are provided on each annular plate 6301 at intervals in the circumferential direction. Two annular groove-shaped valve ports 6201 are axially arranged on the inner hole of the piston seat body 62 at intervals, a plurality of flow passages 6202 are respectively arranged on the two shaft end surfaces of the piston seat body 62 at intervals along the circumferential direction, the flow passages 6202 on the two shaft ends are respectively communicated with the valve ports 6201 on the corresponding sides, when the spool valve 63 moves axially, the opening of the valve ports 6201 can be changed, and the larger the opening of the valve ports 6201, the smaller the damping is, and vice versa.

Sealing end covers 67 are respectively fixed at the two shaft ends of the spool valve 63, and magnetorheological fluid is filled in the spool valve 63;

the middle part of the magnetic flow piston 61 is provided with an annular part 6101, a plurality of orifices 6102 are arranged on the peripheral wall of the annular part 6101 at intervals along the circumferential direction, the magnetic flow piston 61 is in sliding sleeve joint with the sealing end covers 67 at the two shaft ends of the spool valve 63 (the sealing end covers 67 are provided with Gellan rings sleeved on the magnetic flow piston 61), and the annular part 6101 of the magnetic flow piston 61 is positioned in the spool valve 63; baffle rings 68 are respectively fixed on two ends of the magnetic flow piston 61 (the baffle rings 68 are fixed by adopting threaded connection), and a reset spring 69 sleeved on the magnetic flow piston 61 is connected between the baffle rings 68 on the two ends and the sealing end covers 67 on the corresponding sides; the two ends of the magnetic flow piston 61 are respectively and slidably sleeved with a compressing seat 610, the compressing seat 610 at one end is sleeved at the end part of the piston rod 3, the compressing seat 610 at the other end is sleeved in the piston end cover 66 at the corresponding side, and a safety spring 611 sleeved on the magnetic flow piston 61 is respectively connected between the two compressing seats 610 and the baffle ring 68 at the corresponding side.

Further, a push cover 612 is respectively fixed on the sealing end covers 67 at the two shaft ends of the magnetic flow piston 61, and the push cover 612 is in propping connection with the corresponding reset spring 69.

Further, an adjusting screw 613 is screwed to the piston end cap 66 at the end far from the piston rod 3, and the end of the adjusting screw 613 abuts against the corresponding pressing seat 610.

The piston seat 62 is fixed relative to the piston rod 3 by the piston outer body 65, i.e. their moving paths are consistent, so the opening of the valve port 6201 is mainly determined by the up-and-down movement of the spool 63. The path of the oil is shown in fig. 6 when the oil flows from the rod cavity to the rodless cavity; it is apparent from the figure that the spool 63 slides downward under the oil pressure to generate a gap, and the flow of the hydraulic oil between the gaps becomes a damping force. The principle of fluid flow from the rodless chamber to the rod chamber is substantially the same, except that the spool 63 is moved upward.

The opening of the valve port 6201 is adjusted by the interaction between the magnetic flow piston 61 and the sliding valve in the sliding valve core 63, the magnetic flow piston 61 is mainly used for adjusting the opening pressure of the gap between the sliding valve core 63 and the piston seat 62, the magnetic flow piston 61 needs to cooperate with the exciting coil 64 on the piston seat 62 to work, the action principle of the magnetic flow piston 61 is similar to that of the magneto-rheological fluid damper, the complex valve plate and valve structure are replaced by the throttle hole 6102, meanwhile, the magnetic flow piston 61 is not moved up and down, but the sliding valve core 63 is moved, and the moving of the sliding valve core 63 causes the volumes of the upper part and the lower part of the magnetic flow piston 61 to be inconsistent, so that magneto-rheological fluid is forced to circulate between the throttle holes 6102. When current is supplied to the exciting coil 64 of the piston housing 62, a magnetic field is generated, and the magnetorheological fluid in the spool 63 is changed by the magnetic field. When the magnetic field becomes larger gradually, the magnetorheological fluid is gradually changed to a semi-solid state, and the viscous resistance of the magnetorheological fluid flowing through the orifice 6102 becomes larger continuously in the changing process, so that the sliding resistance of the spool 63 of the spool valve is increased, namely the difficulty of opening the valve gap is larger, and a stronger damping effect is achieved.

In order to enable the spool 63 and the piston housing 62 to be in a closed state in a non-moving state and to be able to slide up and down accurately in time during the up-and-down vibration process, a return spring 69 is added to the spool 63. The magnetic flow piston 61 moves together with the piston rod 3, the piston seat 62 and the piston outer body 65 normally, only the spool 63 is in a relatively floating state, and the spool 63 can slide smoothly between three states of sliding upwards, sliding in the middle and sliding downwards under the action of the return spring 69, so that the opening of the valve port is changed. In order to make the oil pressure act on the spool 63 better, a push cap 612 is added at the seal end cap 67 to increase the area of action of the hydraulic oil with the spool 63. The difficulty in sliding the spool 63 is mainly determined by the force of the oil pressure acting on the push cap 612, the pressure and thrust difference of the return spring 69, and the damping force of the magnetic fluid in the spool 63, which is the main valve opening resistance.

When the magnetic field is large, the magnetorheological fluid in the spool 63 is basically solidified and loses fluidity, so that the magnetorheological piston 61 and the spool 63 are fixedly connected together through the magnetorheological fluid, and at the moment, if the magnetorheological piston 61 is directly fixed on the piston rod 3, the spool 63 cannot move to open the valve, which directly leads to the failure of oil circulation, and even damages parts when the pressure is too high. The magnetic piston 61 is connected to the piston rod 3 by means of a safety spring 611.

Under normal conditions, the magnetic current piston 61 is tightly pressed on the piston rod 3 under the action of the pressing seat 610 and the safety spring 611, and under the condition that the damping provided by magnetic fluid is too large, the magnetic current piston 61 can push the safety spring 611 to slide up and down in the inner hole of the pressing seat 610; the magnetic flow piston 61 and the slide valve core 63 in this process are equivalent to a whole body which slides up and down to open the gap between the piston seat 62 and the slide valve core 63 for overflow, and only the slide valve core 63 should slide in a normal state. The pressing seat 610 at the lower end can be adjusted by the adjusting screw 613 to adjust the pre-tightening force of the safety spring 611, and the hydraulic pressure can overflow as long as the hydraulic pressure is greater than the pre-tightening force.

In summary, the oil magnetofluid damper can change the damping of the damper without replacing hydraulic oil, which is mainly beneficial to the internal magneto-rheological valve piston mechanism. Compared with those magneto-rheological fluid dampers replacing hydraulic oil, the magneto-rheological fluid damper can well improve the defects of the traditional magneto-rheological fluid damper, simultaneously greatly reduce the uncontrollable factors of the adjustment damping, and has relatively simple control due to a small amount of magneto-rheological fluid in the spool of the spool valve; compared with the method that the whole damper cylinder is filled with magnetorheological fluid, the novel damper has smaller exciting current and more flexible reaction; the components of conventional dampers, whether they are on a magnetorheological spool piston mechanism or on an end cap seal, can be used in common, as the damping medium is still hydraulic oil, which also gives better linear damping.

The practice of the utility model is described above with reference to the accompanying drawings, but the utility model is not limited to the specific embodiments described above, which are intended to be illustrative rather than limiting, and it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the utility model, and are intended to be included within the scope of the appended claims and description.

Claims

1. The oil magnetofluid damper comprises a cylinder body, a floating separation piston and a piston rod, wherein a bottom end cover and a top end cover are respectively fixed at the bottom and the top of the cylinder body, the floating separation piston is sleeved in the cylinder body in a sliding manner, the space between the floating separation piston and the bottom end cover in the cylinder body is an air chamber and stores air with certain pressure, and the space between the floating separation piston and the top end cover in the cylinder is an oil chamber for filling hydraulic oil; the method is characterized in that:

the slide valve core is sleeved on the inner hole of the piston seat body in a sliding manner, a plurality of annular plates are arranged on the outer circumferential wall of the slide valve core at intervals along the axial direction, and a plurality of flow holes are respectively arranged on each annular plate at intervals along the circumferential direction; two annular groove-shaped valve ports are axially arranged on the inner hole of the piston seat body at intervals, a plurality of flow passages are respectively arranged on the two shaft end surfaces of the piston seat body at intervals along the circumferential direction, each flow passage at the two shaft ends is respectively communicated with a valve port at the corresponding side, and the opening degree of the valve port can be changed when the spool valve moves along the axial direction;

2. The oil magnetofluid damper of claim 1, wherein: the outer ring of the piston outer body is provided with a combined sealing ring, and the combined sealing ring is used for dynamic sealing in the process that the piston outer body slides along the inside of the cylinder body.

3. The oil magnetofluid damper of claim 1, wherein: and the seal end cover is provided with a Gelai ring sleeved on the magnetic flow piston.

4. The oil magnetofluid damper of claim 1, wherein: and the sealing end covers at the two shaft ends of the magnetic flow piston are respectively fixed with a push cover which is propped against and connected with the corresponding reset spring.

5. The oil magnetofluid damper of claim 1, wherein: the end cover of the piston far away from one end of the piston rod is connected with an adjusting screw in a threaded manner, and the end part of the adjusting screw is propped against the corresponding compression seat.