阅读说明：本技术 一种磁流体角速度传感器水银环及其胶接方法 (Mercury ring of magnetic fluid angular velocity sensor and bonding method thereof ) 是由 胡雄超 吴建铭 符德华 沈杰 徐亚娟 忽伟 武斌 陆建 于 2020-11-04 设计创作，主要内容包括：本发明公开了一种磁流体角速度传感器水银环及其胶接方法,包括电极、内筒和外筒；所述的电极包括上电极和下电极；所述的内筒和外筒为同轴放置的空心圆柱,固定于所述的上电极和下电极之间；在所述的电极与所述的内筒和外筒的接触部上,分别设有环形的凹槽,其包含内凹槽和外凹槽,所述的内筒和外筒能分别插入所述的内凹槽和外凹槽内,使所述的内筒和外筒之间形成一个密闭腔体,所述的密闭腔体内充满水银；位于同一电极上的两个所述的凹槽之间为一凸起结构。本发明设计了凹槽和储胶槽,增加胶接面面积,确保胶接有效性；对胶接过程中的气泡进行控制,对胶接面的堆胶高度进行定量控制,既保证胶接面密封,又保证水银环对角振动的测量精度。(The invention discloses a mercury ring of a magnetic fluid angular velocity sensor and a bonding method thereof, wherein the mercury ring comprises an electrode, an inner cylinder and an outer cylinder; the electrodes comprise an upper electrode and a lower electrode; the inner cylinder and the outer cylinder are hollow cylinders which are coaxially arranged and are fixed between the upper electrode and the lower electrode; annular grooves are respectively arranged on the contact parts of the electrode and the inner cylinder and the outer cylinder, and each annular groove comprises an inner groove and an outer groove, the inner cylinder and the outer cylinder can be respectively inserted into the inner groove and the outer groove, so that a closed cavity is formed between the inner cylinder and the outer cylinder, and mercury is filled in the closed cavity; and a convex structure is arranged between the two grooves on the same electrode. The invention designs the groove and the glue storage groove, increases the area of the glue joint surface and ensures the effectiveness of glue joint; the air bubbles in the gluing process are controlled, and the glue stacking height of the gluing surface is quantitatively controlled, so that the sealing of the gluing surface is ensured, and the measurement precision of the diagonal vibration of the mercury ring is also ensured.)

1. A mercury ring of a magnetic fluid angular velocity sensor is characterized by comprising an electrode, an inner cylinder and an outer cylinder; the electrodes comprise an upper electrode and a lower electrode; the inner cylinder and the outer cylinder are hollow cylinders which are coaxially arranged and are fixed between the upper electrode and the lower electrode; the contact parts of the electrode and the inner cylinder and the outer cylinder are respectively provided with an annular groove which comprises an inner groove and an outer groove, the inner cylinder and the outer cylinder can be respectively inserted into the inner groove and the outer groove, so that a closed cavity is formed between the inner cylinder and the outer cylinder, and mercury is filled in the closed cavity.

2. The mercury ring of the magnetorheological fluid angular velocity sensor of claim 1, wherein a raised structure is arranged between two grooves on the same electrode, two side walls of the raised structure are respectively provided with a glue storage groove, and the glue storage grooves are close to the bottom surfaces of the grooves, so that the raised structure is a T-shaped structure.

3. The mercury ring of claim 1, wherein the inner and outer cylinders are made of an insulating and see-through material.

4. A method of gluing a mercury ring of a magnetorheological fluid angular velocity sensor according to claim 1, comprising:

step 1, after a glue dispensing needle is used for coating the inner groove of the upper electrode or the lower electrode with a glue, the inner cylinder is vertically inserted into the inner groove of the upper electrode or the lower electrode;

step 2, measuring the height H of glue stacking, wherein the height H of glue stacking is the distance from the top surface of the T-shaped structure to the highest point of the glue overflowing from the groove; when H is 0, a glue dispensing needle is used for additionally coating the adhesive; when H >1mm, wiping or scraping the excess cement until 0< H <1 mm;

step 3, after the outer groove of the upper electrode or the lower electrode is fully coated with the adhesive by using a dispensing needle, vertically inserting the outer cylinder into the outer groove of the upper electrode or the lower electrode, and repeating the step 2;

step 4, using a dispensing needle to fully coat the inner groove and the outer groove of the lower electrode or the upper electrode with the adhesive, vertically inserting the inner cylinder and the outer cylinder which are glued with the upper electrode or the lower electrode in the step 3 into the lower electrode or the upper electrode, and repeating the step 2;

and 5, standing until the cement is solidified.

5. The method for cementing a mercury ring of a magnetic fluid angular velocity sensor according to claim 4, wherein before the step 1, the method further comprises the following steps:

s1.1, cleaning the inner cylinder, the outer cylinder and the electrode to smooth the surfaces of the inner cylinder, the outer cylinder and the electrode; then placing the mixture into a high-temperature box, setting the temperature to be higher than 80 ℃, and baking for more than half an hour;

s1.2, placing the cementing agent into a vacuum tank and vacuumizing until the air pressure is lower than 10^-2Pa, exhausting air bubbles in the adhesive.

6. The method for cementing the mercury ring of the magnetorheological fluid angular velocity sensor according to claim 4, wherein in the step 2, before the cement is cured, a non-woven fabric is used for wiping off the excess cement; after the cement is cured, a knife is used to scrape off excess cement.

7. The method of cementing a mercury ring of a magnetorheological fluid angular velocity sensor according to claim 4, further comprising:

step 6, using a microscope to inspect the glued surfaces of the upper electrode and the lower electrode, and using a glue dispensing needle to additionally coat the glue-bonding unsaturated part; and (4) retesting the stacking height H, so that H is more than 0 and less than 1 mm.

8. The method according to claim 4, wherein after the inner cylinder or the outer cylinder is vertically inserted into the electrode, the assembly is tilted back and forth several times from left to right to tear the bubbles at the glued surface.

9. The method of claim 8, wherein each tilt angle is no more than 45 °.

Technical Field

The invention relates to the field of angular velocity sensors, in particular to a mercury ring of a magnetic fluid angular velocity sensor and a cementing method thereof.

Background

The magnetic fluid angular velocity sensor is based on Magnetohydrodynamics (MHD), can carry out high-precision measurement on angular velocity and angular displacement, has the characteristics of miniaturization, wide frequency and high stability, is mainly applied to high-precision satellite platforms, deep space optical communication and high-resolution astronomical observation, and has wide application prospects in the fields of civil automobiles and industrial processing and manufacturing.

The mercury ring is a core component of the magnetic fluid angular velocity sensor, and by utilizing the inertia of mercury, when angular vibration is generated outside, mercury cuts magnetic lines of force to generate induced electromotive force, and angular motion information is converted into electric signal information, so that the aim of quantitatively measuring the angular vibration is fulfilled.

The current magnetofluid angular velocity sensor mercury ring glue joint has the main problems that:

(1) the glued joint is not sealed, so that mercury leaks out of the glued joint;

(2) bubbles are generated in the cementing agent in the cementing process, the bubbles are broken or communicated under the influence of external force, and mercury flows out of the mercury ring from the bubbles;

(3) the amount of cement used is difficult to control. Excessive glue generates overflow glue, which affects the measurement precision; too little glue results in a mercury ring that is not sealed and mercury leaks.

Disclosure of Invention

In order to improve the qualified rate of the cementing of the mercury ring of the magnetic fluid angular velocity sensor and the measurement precision of the sensor, the invention provides the mercury ring of the magnetic fluid angular velocity sensor, which comprises an electrode, an inner cylinder and an outer cylinder; the electrodes comprise an upper electrode and a lower electrode; the inner cylinder and the outer cylinder are hollow cylinders which are coaxially arranged and are fixed between the upper electrode and the lower electrode; the contact parts of the electrode and the inner cylinder and the outer cylinder are respectively provided with an annular groove which comprises an inner groove and an outer groove, the inner cylinder and the outer cylinder can be respectively inserted into the inner groove and the outer groove, so that a closed cavity is formed between the inner cylinder and the outer cylinder, and mercury is filled in the closed cavity.

Preferably, a protruding structure is arranged between the two grooves on the same electrode, two side walls of the protruding structure are respectively provided with a glue storage groove, and the glue storage grooves are close to the bottom surfaces of the grooves, so that the protruding structure is of a T-shaped structure.

Preferably, the inner cylinder and the outer cylinder are made of insulating perspective materials.

The invention also provides a cementing method of the mercury ring of the magnetic fluid angular velocity sensor, which comprises the following steps:

step 1, after a glue dispensing needle is used for coating the inner groove of the upper electrode or the lower electrode with a glue, the inner cylinder is vertically inserted into the inner groove of the upper electrode or the lower electrode;

step 2, measuring the height H of glue stacking, wherein the height H of glue stacking is the distance from the top surface of the T-shaped structure to the highest point of the glue overflowing from the groove; when H is 0, a glue dispensing needle is used for additionally coating the adhesive; when H >1mm, wiping or scraping the excess cement until 0< H <1 mm;

step 3, after the outer groove of the upper electrode or the lower electrode is fully coated with the adhesive by using a dispensing needle, vertically inserting the outer cylinder into the outer groove of the upper electrode or the lower electrode, and repeating the step 2;

step 4, using a dispensing needle to fully coat the inner groove and the outer groove of the lower electrode or the upper electrode with the adhesive, vertically inserting the inner cylinder and the outer cylinder which are glued with the upper electrode or the lower electrode in the step 3 into the lower electrode or the upper electrode, and repeating the step 2;

and 5, standing until the cement is solidified.

Preferably, before step 1, the method further comprises:

s1.1, cleaning the inner cylinder, the outer cylinder and the electrode to smooth the surfaces of the inner cylinder, the outer cylinder and the electrode; then placing the mixture into a high-temperature box, setting the temperature to be higher than 80 ℃, and baking for more than half an hour;

s1.2, placing the cementing agent into a vacuum tank and vacuumizing until the air pressure is lower than 10^-2Pa, exhausting air bubbles in the adhesive.

Preferably, in the step 2, before the adhesive is cured, a non-woven fabric is used for wiping off the excess adhesive; after the cement is cured, a knife is used to scrape off excess cement.

Preferably, the method further comprises the following steps:

step 6, using a microscope to inspect the glued surfaces of the upper electrode and the lower electrode, and using a glue dispensing needle to additionally coat the glue-bonding unsaturated part; and (4) retesting the stacking height H, so that H is more than 0 and less than 1 mm.

Preferably, after the inner cylinder or the outer cylinder is vertically inserted into the electrode, the assembly is inclined back and forth for a plurality of times from left to right, and air bubbles on the glued joint surface are torn.

Preferably, the angle of each inclination does not exceed 45 °.

The invention has the beneficial effects that:

(1) the structure of the mercury ring is improved, and a groove and a glue storage groove are designed, so that the area of a glue joint surface is increased, and the gluing effectiveness is ensured;

(2) controlling air bubbles in the gluing process: removing bubbles in the adhesive in vacuum, pre-baking the parts at high temperature before bonding, and extruding bubbles by rotating the inner cylinder and the outer cylinder to prevent mercury from leaking out of a water silver ring from the bubbles due to unsealed bonding surfaces;

(3) the glue stacking height of the glue joint surface is quantitatively controlled (0< H <1mm), so that the sealing of the glue joint surface is ensured, and the measurement precision of the diagonal vibration of the mercury ring is also ensured.

Drawings

FIG. 1 is a cross-sectional view of a mercury ring of a magnetic fluid angular velocity sensor of the present invention.

FIG. 2 is a cross-sectional view of the mercury ring glue joint of the magnetic fluid angular velocity sensor of the present invention.

Fig. 3 is a flow chart of a method for cementing a mercury ring of a magnetic fluid angular velocity sensor according to the present invention.

In the figure, 1-upper electrode, 2-lower electrode, 3-inner cylinder, 4-outer cylinder, 5-groove and 6-glue storage tank.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

As shown in fig. 1, the invention provides a mercury ring of a magnetic fluid angular velocity sensor, which comprises an upper electrode 1, a lower electrode 2, an inner cylinder 3 and an outer cylinder 4; the inner cylinder 3 and the outer cylinder 4 are hollow cylinders which are coaxially arranged and are fixed between the upper electrode 1 and the lower electrode 2. The inner barrel 3 and the outer barrel 4 are made of insulating perspective materials, and the characteristics of insulation, water-silver corrosion resistance and convenience for observing glue stacking height are met. Annular grooves 5 are respectively arranged on the contact parts of the electrode and the inner cylinder 3 and the outer cylinder 4, and comprise inner grooves and outer grooves, the inner cylinder 3 and the outer cylinder 4 can be respectively inserted into the inner grooves and the outer grooves, so that a closed cavity is formed between the inner cylinder 3 and the outer cylinder 4, and mercury is filled in the closed cavity; and a convex structure is arranged between the two grooves on the same electrode.

As shown in fig. 2, two side walls of the protruding structure are respectively provided with a glue storage tank 6, and the glue storage tank 6 is close to the bottom surface of the groove 5, so that the protruding structure is a T-shaped structure. In the process of gluing, the glue can flow into and fill the glue storage groove 6, so that the gluing area is increased, and the effectiveness of gluing is ensured.

As shown in fig. 3, the method for gluing the mercury ring of the magnetic fluid angular velocity sensor comprises three parts, namely a gluing preparation stage, a gluing stage and gluing effectiveness detection.

Examples

(1) Preparation stage of adhesive bonding

S1.1, cleaning the inner cylinder, the outer cylinder and the electrode to smooth the surfaces of the inner cylinder, the outer cylinder and the electrode; because bubbles are possibly generated on the gluing surfaces in the gluing process, the cleaned inner cylinder, outer cylinder and electrode are placed in a high-temperature box, the temperature is set to be higher than 80 ℃, and the baking is carried out for more than half an hour, so that the surfaces of all parts are kept dry;

s1.2, because the adhesive has bubbles during mixing, putting the adhesive into a vacuum tank and vacuumizing until the air pressure is lower than 10^-2Pa, exhausting air bubbles in the adhesive.

(2) Adhesive bonding stage

Step 1, after a glue dispensing needle is used for coating the inner groove of the upper electrode or the lower electrode with a glue, the inner cylinder is vertically inserted into the inner groove of the lower electrode;

step 2, tilting the inserted assembly back and forth for a plurality of times from left to right, wherein the tilting angle does not exceed 45 degrees each time, tearing the bubbles generated on the adhesive joint surface, and preventing the mercury from leaking from the bubbles on the adhesive joint surface; in order to ensure the effectiveness of the glue joint, the glue storage tank and the groove are filled with the glue and overflow from the groove, and a glue stacking height H exists, wherein H is greater than 0. Measuring the glue stacking height H by using a vernier caliper, wherein the glue stacking height H is the distance from the top surface of the T-shaped structure to the highest point of the glue overflowing from the groove; when H is 0 (namely, the cement does not come from the groove), a dispensing needle is used for additionally applying the cement; in order to ensure that the induced electromotive force generated by the mercury ring of the magnetic fluid angular velocity sensor is uniform during vibration and reduce low-frequency errors, when H is larger than 1mm, before the adhesive is cured, the non-woven fabric is used for wiping off redundant adhesive; after the cement is cured, scraping the excess cement with a knife until 0< H <1 mm;

step 3, after the outer groove of the lower electrode is fully coated with the adhesive by using the dispensing needle, vertically inserting the outer cylinder into the outer groove of the lower electrode, and repeating the step 2;

step 4, using a dispensing needle to fully coat the inner groove and the outer groove of the upper electrode with the adhesive, vertically inserting the inner cylinder and the outer cylinder which are glued with the lower electrode in the step 3 into the upper electrode, and repeating the step 2;

and 5, standing until the cement is solidified.

(3) Detection of effectiveness of adhesive bonding

Inspecting the glued surfaces of the upper electrode and the lower electrode by using a microscope, and coating the glue-unsaturated positions by using a glue dispensing needle; and (4) retesting the stacking height H, so that H is more than 0 and less than 1 mm.

In summary, the invention provides a mercury ring of a magnetic fluid angular velocity sensor and a bonding method thereof, which improves the existing mercury ring structure of the magnetic fluid angular velocity sensor, designs a groove and a glue storage groove, increases the bonding surface area, and ensures the bonding effectiveness. The pretreatment of each part in the gluing preparation stage reduces the possibility of air bubble generation in the gluing process; in the gluing stage, the glued device is inclined back and forth from left to right to extrude and tear the bubbles; the height of the stacked glue is controlled to be 0< H <1mm, so that mercury can uniformly cut magnetic lines of force, the generated current is stable, and the measurement precision of the mercury ring is ensured.

While the present invention has been described in detail with reference to the preferred embodiments, it should be understood that the above description should not be taken as limiting the invention. Various modifications and alterations to this invention will become apparent to those skilled in the art upon reading the foregoing description. Accordingly, the scope of the invention should be determined from the following claims.