CN102705107A

CN102705107A - Solid chemical micro-thruster

Info

Publication number: CN102705107A
Application number: CN2012101401382A
Authority: CN
Inventors: 谢建兵; 申强; 李小平; 张和民; 常洪龙
Original assignee: Northwestern Polytechnical University
Current assignee: Northwestern Polytechnical University
Priority date: 2012-05-06
Filing date: 2012-05-06
Publication date: 2012-10-03
Anticipated expiration: 2032-05-06
Also published as: CN102705107B

Abstract

The invention discloses a solid chemical micro-thruster and belongs to the field of micro-propulsion technology and MEMS (micro-electro mechanical systems). The micro-thruster is formed by bonding of a silicon wafer and heat resistant glass, surfaces 2 of an upper silicon wafer 1 concave inward to form a combustion chamber 4 and a nozzle 3, a throat at a communication position of the combustion chamber 4 and the nozzle 3 is an arc with the curvature radius R, and a lower glass sheet 7 is formed by the heat resistant glass 8 and an ignition circuit structure on the heat resistant glass 8. The solid chemical micro-thruster has the advantages that ignition grooves are in the form of straight lines, and accordingly difficulty of silicon glass bonding is lowered by the aid of the straight line type ignition grooves under the conditions of the same ignition groove width and bonding area; the throat is the arc with certain curvature radius and is tangent to a boundary of a gas inlet and a gas outlet, so that a gas boundary layer is reduced while thrust of a device is enhanced; and the contact area of an igniter designed by a plurality of resistors in parallel connection and a propellant is increased, a heating area is enlarged, function failure of the whole device caused by fusing of one igniter is avoided, and reliability of the igniter is improved.

Description

The miniature solid chemical propeller

Affiliated field:

The present invention relates to a kind of miniature solid chemical propeller, be used for position maintenance, attitude control, gravitation compensation and the track adjustment etc. of miniature spacecraft, belonged to little Push Technology and MEMS (MEMS) field.

Background technique:

Propulsion system is the key subsystem of most of astrovehicles, is mainly used in position maintenance, attitude control, gravitation compensation and the track adjustment etc. of astrovehicle.Along with minitype spacecraft,,,, be equipped with propulsion system then need for these minitype spacecrafts like satellite formation flying if need minitype spacecraft to accomplish some special duty like little satellite, the continuous maturation of satellite, skin satellite technology of receiving.Because traditional propulsion system volume and quality is all bigger, can not be applicable to minitype spacecraft, so active demand is suitable for high reliability, low power consumption, the microthrust of micro-satellite, the miniature propulsion system of little momentum.

Microdriver based on the MEMS technology structurally improves traditional propulsion device; On technology, combined micro-nano and Micrometer-Nanometer Processing Technology; Have advantages such as be prone to realizing miniaturization, integrated, low power consumption, therefore become the research direction of little propulsion system." Development of a solid propellant microthruster with chamber and nozzle etched on a wafer surface " and " A MEMS-based solid propellant microthruster with Au/Ti igniter " at people such as Zhang K L report; Referring to Fig. 1 and Fig. 2; A kind of employing DRIE technology is proposed; The microdriver that utilizes silicon and glass bonding to form; Microdriver comprises silicon structure layer and glassy layer, and the silicon structure layer has nozzle 3, firing chamber 4 and lower wire groove 5, upper conductor groove 6; Comprise igniter 9 on the glassy layer, go up harness 10, down-firing lead 11, this propulsion device adopt DRIE technology to obtain firing chamber 4, nozzle 3 and metallic channel 5, adopt metal sputtering and etching technics to obtain igniter 9 and harness 10.This angle of rake ignition slot is in the rectangular form of silicon face, and under the certain situation of silicon face bonding area, the ignition slot surface area is big more, and glass and silicon face bonding difficulty are big more; The throat of nozzle and suction port, air outlet intersect wedge angle, and the boundary layer that causes spraying gas increases, and is difficult to produce bigger thrust; And the igniting resistance on glass plate adopts single design form; Heating temperature is the highest at the narrowest place of igniter live width in the igniter energising back of single design form; Be easy to generate the fusing phenomenon, cause the irreversible inefficacy of igniter, so the angle of rake ignition slot structure that people such as Zhang proposes exists silicon glass bonding difficulty big; Problems such as gas boundary layer increases and can't increase thrust, and the igniter reliability is low.

Summary of the invention:

The objective of the invention is: big for overcoming in the existing microdriver technology silicon glass bonding technology difficulty; Gas boundary layer can't increase thrust and the low shortcoming of igniter reliability greatly, and the present invention proposes a kind of employing silicon chip and thermal glass forms microdriver through bonding technology.

As shown in Figure 3, the technological scheme that the present invention adopted is: the miniature solid chemical propeller comprises the upper strata silicon chip 1 and lower floor's glass sheet 7 of bonding; Silicon chip 1 surperficial 2 indents in said upper strata form firing chamber 4 and nozzle 3; The throat of firing chamber 4 and nozzle 3 connections place is that radius of curvature is the circular arc of R, and throat opening r satisfies: r=R; 4 relative both sides, firing chamber have rectilinear lower wire groove 5 and upper conductor groove 6 respectively; The degree of depth of lower wire groove 5 and upper conductor groove 6 is less than the degree of depth of firing chamber 4 and nozzle 3; Said lower floor glass sheet 7 is made up of thermal glass 8 and the firing circuit structure on it, and the firing circuit structure comprises the igniter 9 with 4 corresponding positions, firing chamber, and igniter 9 is many parallel firing devices; Igniter 9 two ends are connected with last harness 10 that is positioned at lower wire groove 5 and the down-firing lead 11 that is positioned at ignition slot 6 respectively; Last harness 10 is connected with following pad 13 with the outer last pad 12 of upper strata silicon chip 1 respective regions with down-firing lead 11; The thickness of last harness 10 and down-firing lead 11 is less than the degree of depth of down-firing groove 5 and last ignition slot 6, make igniter 9 on upper strata silicon chip 1 and the lower floor's glass sheet 7, go up harness 10, down-firing lead 11, go up pad 12 and following pad 13 non-contacts.

During work; Through last pad 12, down pad 13, go up harness 10, down-firing lead 11 switches on for the igniter 9 that is positioned at firing chamber 4; Igniter 9 temperature raise and reach the ignition temperature of firing chamber 4 fuel, ignited fuel, and pressure increases in the firing chamber 4; Gas produces and advances effect through nozzle 3 ejection.

The invention has the beneficial effects as follows: ignition slot is in silicon face form linearly, and under identical ignition slot width and bonding area, linear ignition slot makes silicon glass bonding difficulty reduce; Throat be processed into circular arc with certain curvature radius and make it and the border of suction port, air outlet tangent, reduce gas boundary layer, improve the thrust of device; Adopt the igniter of many resistance parallel connection design forms to increase the area of contact with propellant agent, enlarge heating region, the fusing because of an igniter does not cause the entire device disabler, has improved the reliability of igniter

Below in conjunction with accompanying drawing and embodiment the present invention is further specified.

Description of drawings

Fig. 1 is MEMS propulsion device firing chamber and a nozzle arrangements schematic representation in the existing technology;

Fig. 2 is a MEMS propulsion device firing circuit structural representation in the existing technology;

Fig. 3 is the miniature solid chemical propeller structural representation among the present invention;

Fig. 4 is the upper strata silicon chip structural representation among the embodiment;

Fig. 5 is the lower floor's glass sheet structural representation among the embodiment;

Fig. 6 is the structure enlarged diagram of the igniter among the embodiment;

Among the figure, 1-upper strata silicon chip, 2-surface, 3-nozzle, 4-firing chamber, 5-lower wire groove, 6-upper conductor groove, 7-lower floor glass sheet, 8-thermal glass, 9-igniter, the last harness of 10-, 11-down-firing lead, the last pad of 12-, pad under the 13-.

Embodiment:

Embodiment 1:

Consult Fig. 3-6, the miniature solid chemical propeller in the present embodiment comprises the upper strata silicon chip 1 and lower floor's glass sheet 7 of bonding; Silicon chip 1 surperficial 2 indents, 500 μ m in said upper strata form firing chamber 4 and nozzle 3; The throat of firing chamber 4 and nozzle 3 connections place is that radius of curvature is the circular arc of 500 μ m, and throat opening r also is 500 μ m; 4 relative both sides, firing chamber have rectilinear lower wire groove 5 and upper conductor groove 6 respectively; The degree of depth of lower wire groove 5 and upper conductor groove 6 is 1 μ m; Said lower floor glass sheet 7 is made up of thermal glass 8 and the firing circuit structure on it, and thermal glass 8 is Pyrex7740 in the present embodiment; The firing circuit structure comprises the igniter 9 with 4 corresponding positions, firing chamber, and igniter 9 is the snakelike rugosity crome metal film resistor of two parallel connections, and thickness is 200nm; Igniter 9 two ends are connected with last harness 10 that is positioned at lower wire groove 5 and the down-firing lead 11 that is positioned at upper conductor groove 6 respectively; Last harness 10 is connected with following pad 13 with the outer last pad 12 of upper strata silicon chip 1 respective regions with down-firing lead 11; Last harness 10, down-firing lead 11, the material of going up pad 12 and following pad 13 are copper; The thickness of last harness 10 and down-firing lead 11 is 200nm, make igniter 9 on upper strata silicon chip 1 and the lower floor's glass sheet 7, go up harness 10, down-firing lead 11, go up pad 12 and following pad 13 non-contacts;

During work; Through last pad 12, down pad 13, go up harness 10, down-firing lead 11 switches on for the igniter 9 that is positioned at firing chamber 4; 350 ° of the ignition temperatures that igniter 9 temperature raise and to reach firing chamber 4 fuel HTPB/AP, ignited fuel, pressure increase in the firing chamber 4; Gas produces and advances effect through nozzle 3 ejection.

Claims

1. miniature solid chemical propeller comprises upper strata silicon chip (1) and lower floor's glass sheet (7) of bonding, and it is characterized in that: said upper strata silicon chip (1) surface (2) indent forms firing chamber (4) and nozzle (3); The throat of firing chamber (4) and nozzle (3) connection place is that radius of curvature is the circular arc of R, and throat opening r satisfies: r=R; Firing chamber (4) has rectilinear lower wire groove (5) and upper conductor groove (6) respectively in both sides relatively; The degree of depth of lower wire groove (5) and upper conductor groove (6) is less than the degree of depth of firing chamber (4) and nozzle (3); Said lower floor glass sheet (7) is made up of thermal glass (8) and the firing circuit structure on it, and the firing circuit structure comprises and the igniter (9) of corresponding position, firing chamber (4) that igniter (9) is many parallel firing devices; Igniter (9) two ends are connected with last harness (10) that is positioned at lower wire groove (5) and the down-firing lead (11) that is positioned at ignition slot (6) respectively; Last harness (10) is connected with following pad (13) with the outer last pad (12) of upper strata silicon chip (1) respective regions with down-firing lead (11); The thickness of last harness (10) and down-firing lead (11) is less than the degree of depth of down-firing groove (5) and last ignition slot (6), make igniter (9) on upper strata silicon chip (1) and the lower floor's glass sheet (7), go up harness (10), down-firing lead (11), go up pad (12) and following pad (13) non-contact.