CN104847826A - Inner taper angle magnetic liquid damping shock absorber - Google Patents

Abstract

The utility model relates to an inner cone angle magnetic liquid damping shock absorber, which belongs to the field of mechanical engineering vibration. It successfully solves the problem that the existing magnetic liquid damping shock absorber cannot be applied in engineering practice due to various structural problems. The device includes a shell (1), a magnetic liquid (2), a left permanent magnet (3), a connecting rod (4), a right permanent magnet (5), a right end cover (6), a ventilation groove (7), a left end cover ( 8), when the outside world vibrates, the magnetic liquid moves together with the mass block composed of the left permanent magnet (3) and the right permanent magnet (5), thereby absorbing energy, the left permanent magnet (3), the connecting rod (4) and the right The permanent magnet (5) forms a frequency difference between the mass blocks due to the effect of the cone angle, so that the vibration reduction efficiency reaches the maximum.

Description

An inner cone angle magnetic liquid damping shock absorber

technical field

The invention relates to an inner cone angle magnetic liquid damping shock absorber, which is suitable for vibration reduction of long and straight objects in spacecraft.

Background technique

The magnetic liquid damping shock absorber is a passive shock absorber with high sensitivity to inertial force, and has the advantages of simple structure, small size, large energy consumption and long life. Due to the special operating environment of the spacecraft, its own volume, weight and energy are limited to a certain extent, so the magnetic liquid damping shock absorber is very suitable for the low-frequency, small-amplitude vibration reduction of long and straight objects in large spacecraft, such as the solar energy of the space station. At the same time, it also has broad application prospects on the ground, such as vibration reduction of high-power antennas up to 100 meters long, vibration reduction of precision balances, etc. However, the existing magnetic liquid damping shock absorbers cannot be applied in engineering practice due to various structural problems. The specific problems are as follows:

Now the most common magnetic liquid damping shock absorber mainly adopts the second-order buoyancy principle of magnetic liquid, as described in reference 1 (patent application for publication number CN102032304A), reference 2 (patent application for publication number CN104074903A), comparison Described in document 3 (patent application for publication number CN102042359A), described in comparative document 4 (publication number CN102494070A), described in comparative document 5 (publication number JP11-230255A) and comparative document 6 (publication number CN103122965A), a few have adopted magnetic The principle of first-order buoyancy of liquid is described in reference 7 (patent application with publication number JP11-223247A).

For the shock absorber device described in Comparative Document 1 (patent application with publication number CN102032304A), the shock absorber includes a non-magnetic shell, a magnetic liquid, a permanent magnet, nuts, end caps, bolts, screws, gaskets, and an O-shaped sealing ring. The patent application uses a cylindrical permanent magnet as a mass, and fills the non-magnetic shell with magnetic liquid, so that the mass is suspended in the shell by using the second-order buoyancy principle of the magnetic liquid. When the outside vibrates, the relative motion between the mass block and the shell causes the magnetic fluid to flow in the gap between the mass block and the shell, resulting in viscous loss. The shock absorber described in this patent utilizes the second-order buoyancy principle of magnetic liquid, and the permanent magnet can be stably suspended in the shell by filling the shell with magnetic liquid. However, due to the magnetic viscous effect of the magnetic liquid, when the magnetic liquid fills the shell After the housing, the permanent magnet will move very slowly inside the housing, and the vibration reduction effect is not good. Secondly, since the mass block is a permanent magnet and the shell is a common cylindrical barrel, the weight of the mass block and the magnitude of the restoring force cannot be adjusted, so it is not practical in engineering applications.

The shock absorber device described in Comparative Document 2 (patent application with publication number CN104074903A), the shock absorber includes a non-magnetic shell, bolts, nuts, permanent magnets, magnetic liquid, non-magnetic shell, O-rings, air holes , annular gap, etc. The patent application also uses the permanent magnet as a mass, and absorbs a small amount of magnetic liquid at both ends of the permanent magnet. The second-order buoyancy principle of the magnetic liquid is used to make the permanent magnet suspend. The inner wall of the shell is processed into an arc shape to make the magnetic liquid generate elastic force. , so that the permanent magnet is always in the middle of the housing. At the same time, this structure does not need to fill the entire casing with magnetic liquid, thereby avoiding the difficulty of flowing at both ends of the permanent magnet after the magnetic liquid is filled in Reference Document 1. However, when the mass block moves, the entire mass block will be deflected, resulting in scratching between the bottom surface of the mass block and the arc-shaped inner wall of the shell, resulting in ineffective vibration reduction. At the same time, the air hole used in this patent needs to be connected with a jacket, and the structure is complex. This results in an increase in the mass of the entire shock absorber and is therefore impractical.

The shock absorber device described in comparative document 3 (the patent application with publication number CN102042359A), the shock absorber is similar to the device structure described in comparative document 1, but comparative document 3 has 4 to 8 through-holes on the permanent magnet. The through hole can make the magnetic fluid flow more smoothly and increase the friction area. However, since the magnetic liquid fills the entire cavity, and the magnetic field at both ends of the permanent magnet is very strong, both the magnetic liquid in the through hole and the magnetic liquid between the permanent magnet and the housing will not flow normally due to excessive viscosity, so in The effect of processing the through hole on the permanent magnet is not obvious, so it is not practical.

For the shock absorber device described in comparative document 4 (patent application with publication number CN102494070A), the principle of the shock absorber is similar to that of the device described in comparative document 1, but the device described in this patent processes the shell into a circular hollow spherical shape , The permanent magnet is processed into a solid spherical shape. However, pure shape change cannot solve the problem of difficult flow of magnetic liquid between the permanent magnet and the housing, so it is not practical.

Compared with the shock absorber described in Document 5 (patent application with Publication No. JP11-230255A), the shock absorber is a shock absorber for shaft vibration, which utilizes the second-order buoyancy principle of magnetic liquid and uses permanent magnets as A rotating mass. This patent also cannot solve the problem that the magnetic liquid is difficult to flow between the permanent magnet and the housing, so it is not practical.

Compared with the shock absorber device described in document 6 (patent application with publication number CN103122965A), the shock absorber is a shock absorber for reducing the vibration of solar sail panels, which utilizes the second-order buoyancy principle of magnetic liquid, and the mass The block is an annular permanent magnet. This patent maintains the central position of the permanent magnet by using a spacer with a cone angle. However, when the cylindrical permanent magnet moves at the bottom of the housing, it will be inclined due to the action of the cone angle spacer, which will cause the permanent magnet and the spacer to scrape. Rubbing, viscous energy consumption is reduced, so there are certain problems in practical applications.

Compared with the shock absorber device described in Document 7 (patent application with publication number JP11-223247A), the shock absorber is a shock absorber for reducing the vibration of the rotating shaft, which utilizes the first-order buoyancy principle of the magnetic liquid, and the mass The block is a ring-shaped non-magnetic material, and a circle of permanent magnets is installed on the rotating shaft so that the mass block does not shift in the circumferential direction. However, according to the principle of first-order buoyancy of magnetic liquid, a single set of permanent magnets is unstable for the suspension of non-magnetic materials, which can easily cause the mass block to shift and disturb in the axial direction of the rotating shaft. Therefore, this patent does not Has practical value.

Therefore, it is urgent to redesign and improve the structure of the magnetic liquid damping shock absorber so that it can be applied in practical engineering.

Contents of the invention

The technical problem to be solved by the present invention is that the existing magnetic liquid damping shock absorber cannot be applied in engineering practice due to problems such as magnetic liquid flow caused by various structural defects. In particular, an inner cone angle magnetic liquid damping shock absorber is provided.

The technical scheme that the present invention solves technical problem adopts is:

An inner cone angle magnetic liquid damping shock absorber, the device includes a shell, a magnetic liquid, a left permanent magnet, a connecting rod, a right permanent magnet, a right end cover, a right air hole, a left end cover, and a left air hole.

The housing is provided with an inner hole, the left end of the inner hole is a tapered hole whose diameter gradually decreases from left to right, and the right end of the inner hole is a tapered hole whose diameter gradually decreases from right to left; the left permanent magnet, connecting rod and The right permanent magnet is fixedly connected in turn from left to right to form a working unit, and ensure coaxiality; inject a certain amount of magnetic liquid on the left permanent magnet and the right permanent magnet; Fixed connection. The symmetrical tapered hole formed in the middle of the housing can effectively prevent the problem of scratching between the permanent magnet and the housing.

The shell is made of non-magnetic material, and the taper angle of the taper holes at the left and right ends of the inner hole is 5°≤θ<90°. The tapered holes at the left and right ends of the shell can provide a centering effect for the mass block formed by the left permanent magnet, connecting rod and right permanent magnet, so that the mass block is always subjected to a centering force pointing to the center of symmetry during the vibration process.

The shape and size of the left vent hole and the right vent hole are exactly the same, and they are circular holes, and the area of the left vent hole is greater than or equal to the end face area of the left permanent magnet, and is smaller than the maximum area of the cone hole of the housing, and the area of the right vent hole is larger than It is equal to the end surface area of the right permanent magnet, and is smaller than the maximum area of the taper hole of the housing. The left and right ventilation holes can ensure that the gas on both sides of the chamber will not be compressed due to the movement of the mass block, and their size range can ensure that the fluctuation of the gas pressure at both ends can be minimized, which will affect the movement speed of the mass block.

The left permanent magnet and the right permanent magnet have the same size, and the diameters are larger than the minimum diameter of the taper hole of the casing, and smaller than the maximum diameter of the taper hole of the casing; the diameter of the connecting rod is smaller than the diameter of the left and right permanent magnets, and smaller than the diameter of the casing The minimum diameter of the body taper hole, the material can be magnetic, non-magnetic or permanent magnet and other materials. The size of the left and right permanent magnets can prevent the separation of the left and right permanent magnets from their respective corresponding cone angle parts of the housing due to inertia, resulting in failure of the centering force. The connecting rod can be made of any material that is not easily deformed. When used in space, a magnetically permeable material or a non-magnetically permeable material with a higher density is preferred, such as iron, copper or lead, etc.; when used on the ground, a less dense one is preferred. Non-magnetic materials, such as aluminum, can also be used with permanent magnets. The diameter of the connecting leg is smaller than the minimum diameter of the taper hole, which also prevents the problem of scratching with the wall surface of the housing.

Compared with the prior art, the present invention has the following beneficial effects: (1) the tapered holes at the left and right ends of the housing can provide a centering effect for the mass block formed by the left permanent magnet, connecting rod and right permanent magnet , so that the mass block is always subjected to a centering force pointing to the center of symmetry during the vibration process, and the tapered hole whose diameter gradually decreases from the left and right ends to the middle can prevent the mass block from tilting during the movement process and scraping with the shell wall rub problem; (2) The left and right vent holes can ensure that the gas on both sides of the chamber will not be compressed, resulting in pressure fluctuations, so as not to affect the movement speed of the left and right permanent magnets; (3) The left and right permanent magnets The size can prevent the left and right permanent magnets from detaching from their corresponding shell cone angles due to inertia, resulting in failure of the centering force; (4) The connecting rod allows the mass of the inertial mass to be selected according to environmental requirements, expanding the reduction The scope of use of the vibrator, and its size prevents the direct scratching between the mass block and the shell.

Description of drawings

Fig. 1 is a kind of internal cone angle magnetic liquid damping shock absorber;

Among Fig. 1: housing 1, magnetic liquid 2, left permanent magnet 3, connecting rod 4, right permanent magnet 5, right end cover 6, right vent 7, left end cover 8, left vent 9.

Detailed ways

The present invention will be further described with accompanying drawing as specific embodiment:

An inner cone angle magnetic liquid damping shock absorber, as shown in Figure 1, the shock absorbing device includes: a housing 1, a magnetic liquid 2, a left permanent magnet 3, a connecting rod 4, a right permanent magnet 5, a right end cover 6, a right through Air hole 7, left end cover 8, left air vent 9.

Connections between the parts making up the device:

Firstly, the left permanent magnet 3 and the connecting rod 4 are fixedly connected, and the coaxiality is ensured, and the connection method is the bonding method. Inject a sufficient amount of magnetic liquid 2 on the left permanent magnet 3. Then the above-mentioned connecting body formed by the left permanent magnet 3 and the connecting rod 4 is loaded into the housing 1 from left to right. Then the right permanent magnet 5 is fixedly connected with the connecting body to form a working unit, and the magnetic liquid 2 is injected into the right permanent magnet 5 . Finally, the left end cap 8 and the right end cap 6 are respectively fixedly connected with the left and right end surfaces of the housing 1 by bonding, welding or threaded connection.

The housing 1 and the left and right end caps are made of non-magnetic materials.

The connecting rod 4 can be used to adjust the weight of the entire mass, that is, either a magnetically permeable material or a non-magnetically permeable material, or even a permanent magnet.

Claims (5)

1. a cone angle magnetic fluid damper in, is characterized in that: housing (1), magnetic liquid (2), left permanent magnet (3), pitman (4), right permanent magnet (5), right end cap (6), right vent (7), left end cap (8), left vent (9); Described housing (1) is provided with endoporus, and endoporus left end is the from left to right taper hole that reduces gradually of diameter, and endoporus right-hand member is the taper hole that reduces gradually of diameter from right to left; Described left permanent magnet (3), pitman (4) and right permanent magnet (5) are from left to right fixedly connected sequentially and form working cell, and ensure coaxial; At left permanent magnet (3) and right permanent magnet (5) a certain amount of magnetic liquid of upper injection (2); Described left end cap (8) is fixedly connected with housing (1) left and right end face respectively with right end cap (6); Left end cap (8) is processed with left vent (9), right end cap (6) is processed with right vent (7).

2. cone angle magnetic fluid damper in one according to claim 1, is characterized in that:

Described housing (1) is non-permeable material, the cone angle 5 °≤θ <90 ° of its endoporus left and right two ends taper hole.

3. cone angle magnetic fluid damper in one according to claim 1 and 2, is characterized in that:

Described left vent (9) is identical with right vent (7) shape and size, for hole circle shape, and the area of left vent (9) is more than or equal to the face area of left permanent magnet (3), be less than the maximum area of housing (1) taper hole, the area of right vent (7) is more than or equal to the face area of right permanent magnet (5), is less than the maximum area of housing (1) taper hole.

4. cone angle magnetic fluid damper in one according to claim 1, is characterized in that:

Described left permanent magnet (3) and right permanent magnet (5) measure-alike, and diameter is all greater than the minimum diameter of housing (1) taper hole, is less than the maximum diameter of housing (1) taper hole.

5. cone angle magnetic fluid damper in the one according to claim 1 or 2 or 4, is characterized in that:

Described pitman (4) diameter is less than the diameter of left and right permanent magnet, and is less than the minimum diameter of housing (1) taper hole, and material can select the materials such as magnetic conduction, non-magnetic or permanent magnet.