CN201522974U

CN201522974U - Electromagnetic bistable microrelay

Info

Publication number: CN201522974U
Application number: CN2009202465239U
Authority: CN
Inventors: 李德胜; 郭学平; 刘本东
Original assignee: Beijing University of Technology
Current assignee: Beijing University of Technology
Priority date: 2009-10-30
Filing date: 2009-10-30
Publication date: 2010-07-07
Anticipated expiration: 2019-10-30

Abstract

The utility model relates to an electromagnetic bistable microrelay, belonging to the technical field of manufacturing. The electromagnetic bistable microrelay adopts a structure that a driving coil system, an electrode system, a contact system as well as a magnetic core and an iron core are manufactured on a semiconductor silicon substrate, and then are adhered and combined with a permanent magnet. The driving coil system consists of a driving coil, a lead and two pairs of load electrodes; the lead is connected with central electrodes of two planar driving coils; the contact system consists of two pairs of static contacts, a torsion beam, a support and a rotating shaft which are distributed at the center of a chip; and the magnetic core and the iron core are silicon cups formed by plating a permalloy layer on the three etched surfaces of the back surface of the silicon substrate. The microrelay adopts an integrated basic structure, overcomes the defects of poor reliability, low structural precision and the like of a split type structure, and has the advantages of simple technique, low cost, simple structure, high reliability and the like.

Description

A kind of electromagnetism bistable micro-relay

Technical field

The utility model relates to and utilizes electromagnetic force to drive, and permanent magnetism is tried hard to keep and held the bistable relay based on MEMS (micro electro mechanical system) (MEMS) technology of its stable state, specifically is a kind of electromagnetism bistable micro-relay, belongs to the manufacturing technology field.

Technical background

Relay is widely used in fields such as automatic control system, power protection system, electrical system, communication system and instrument and meter as a kind of basic electric component.

Conventional relay is divided into two big classes: electromechanical relay and solid-state relay.The adhesive that electromechanical relay is based on metal electrode realizes with disconnecting, this relay has the perfect electric property of being close to, and promptly closed impedance is little, the conducting electric current is big, open-circuit impedance is big, leakage current is little, but owing to be Mechanical Contact, its response speed is slow, and working life is also shorter.Solid-state relay is based on the coupling of phototransistor and light-emitting diode.This relay has the insulation property comparable with electromechanical relay, and the compression strength of 1500V can be provided.But solid-state relay is nothing like electromechanical relay on insertion loss and two indexs of load current.Therefore solid-state relay is mainly used in and requires the occasion that reliability is high or requirement is microminiaturized.The price of solid-state relay approximately is more than three times of electromechanical relay in addition.Therefore the performance microminiaturized relay suitable with electromechanical relay with the price relay between electromechanical relay and solid-state relay, particularly performance has the very big market demand.So had in recent years much and invested MEMS (micro electro mechanical system) (MEMS) technology of representing microminiaturized and integrated direction in relay area research personnel's sight.

From the operation principle angle, mainly contain electrostatic, electromagnetic type, hot mechanical type, pyromagnetic type etc., the advantage that it is main based on the relay of micro-electromechanical technology processing technology: volume is little, low in energy consumption, response is fast, isolation is high, load capacity is strong etc.Main research direction concentrates on the relay by static and Electromagnetic Drive, wherein the electrostatic relay has limited it owing to its driving voltage is too high and has further developed, and Electromagnetic Drive is low with its driving voltage, produce that moment is big, the life-span long, the characteristics such as mutual isolation of drive signal and transmission signals become the direction of research and microrelay development.The predicament of electromagnetic relay maximum at present is complex structure, and the electromagnetic field intensity that technology realization difficulty and planar coil thereof produce is little etc.

Utility model content

The utility model purpose is not only to take into account the advantage of traditional relay but also overcome under the not enough situation of existing MEMS relay existence, a kind of little electromagnetic relay of designing and developing, this relay is based on microelectromechanical systems (MEMS) fine process technology, each structure of whole relay (except the permanent magnet (1)) is integrated on the silicon substrate makes, it is big that magnetic circuit is tending towards the closed electromagnetic field intensity, has characteristics such as reliability height, structure and manufacture craft are simple, processing cost is low.

To achieve these goals, the utility model has been taked following technical scheme: this device comprises silicon substrate, the magnetic core iron core system in the lower surface etching of silicon substrate, the drive coil system that makes and the contact system of arranging on drive coil system top on silicon substrate.

Described magnetic core iron core system comprises an iron core and two magnetic cores, the center of described iron core overlaps with the center of silicon substrate, described two magnetic cores are symmetrically distributed with respect to iron core along the direction of silicon substrate center line, described iron core is leg-of-mutton silicon cup for the lower surface at silicon substrate etches cross sectional shape, on silicon cup, be coated with permalloy layer and form iron core, the structure of two magnetic cores is identical with the structure of iron core, also connects by permalloy layer between magnetic core and the iron core; Below iron core and magnetic core, be provided with the protective layer of insulating effect, below protective layer, be fitted with permanent magnet.

Described drive coil system comprise two floor plan drive coil, connect lead and two pairs of load electrodes of drive coil.Be manufactured with the lead of a connection drive coil at the upper surface of silicon substrate, two terminals of lead lay respectively at two coil magnetic cores directly over, whole lead becomes " U " font structure, be manufactured with a layer insulating above the terminal at two that remove lead, on insulating barrier, be manufactured with two planar coils and two pairs of load terminals, the center terminal of planar coil be in lead terminal directly over, and be conducted with conductor terminal, two pairs of load terminals are symmetrically distributed in the both sides of two drive coils respectively;

Described contact system comprises two pairs of fixed contacts, bearing, torsion beam and rotating shafts.On coil, be manufactured with insulating barrier, and expose coil electrode and two pairs of load terminals, on insulating barrier, be manufactured with two pairs of fixed contacts, bearing, torsion beam and rotating shaft, torsion beam, bearing and rotating shaft permalloy layer for electroplating, become " ten " font structure, the center of cross structure overlaps with the center of silicon substrate, torsion beam has identical thickness with rotating shaft, bearing is connected with the rotating shaft two ends, bearing and fixed contact and rotating shaft thickness difference form the working clearance of relay, the two ends of the torsion beam of two pairs of fixed contact symmetric arrangement, and connect one to one with two pairs of load electrodes, its end can contact with fixed contact when torsion beam was rotated.

The utlity model has and make the reliability height, advantages such as driving moment is big, technology is simple, simple in structure, low cost of manufacture.

Description of drawings

The structure cutaway view of Fig. 1 bistable electromagnetic microrelay

Fig. 2 drive coil system and electrode system structure chart

Fig. 3 contact system structure chart

Among the figure: 1, permanent magnet; 2, magnetic core; 3, protective layer; 4, magnetic circuit; 5, silicon substrate; 6, fixed contact; 7, iron core; 8, bearing; 9, coil; 10, insulating barrier; 11, torsion beam; 12, lead; 13, coil electrode; 14, rotating shaft; 15, load terminal.

Embodiment

In conjunction with Fig. 1-Fig. 3 the utility model is described further:

The structure of present embodiment comprises silicon substrate 5, the magnetic core iron core system in the lower surface etching of silicon substrate 5, the drive coil system that makes and the contact system of arranging on drive coil system top as shown in Figure 1 on silicon substrate.Magnetic core iron core system comprises an iron core 7 and two magnetic cores 2.The drive coil system comprises the drive coil 9 of two floor plan, lead 12 and two pairs of load electrodes 5 of connection drive coil.Contact system comprises two pairs of fixed contacts 6, bearing 8, torsion beam 11 and rotating shaft 14.The particular location relation of its each several part is as follows:

As shown in Figure 1, magnetic core iron core system comprises an iron core 7 and two magnetic cores 2, the center of iron core overlaps with the center of silicon substrate, two magnetic cores are symmetrically distributed with respect to iron core 7 along the direction of silicon substrate center line, iron core 7 is leg-of-mutton silicon cup for the lower surface at silicon substrate etches cross sectional shape, the structure that is coated with 7, two magnetic cores 2 of permalloy layer composition iron core on silicon cup is identical with the structure of iron core 7, also connects by permalloy layer between magnetic core 2 and the iron core 7.Below iron core and magnetic core, be provided with the protective layer 3 of insulating effect, below protective layer 3, be fitted with permanent magnet 1.

The structure of drive coil system as shown in Figure 2, on the another side of silicon substrate 5, make the lead 12 of a connection drive coil 9, two terminals of lead 12 are respectively directly over the contre electrode that is positioned at two coil magnetic cores 2, and be conducted with the contre electrode of drive coil, 12 one-tenth " U " fonts of whole lead structure is being removed two making above the terminal, one layer insulating 10 of lead 12, makes lead 12 and drive coil 9 insulation.On insulating barrier 10, be manufactured with two planar coils 9 and four load terminals 15, the center terminal of planar coil 9 be in lead 12 terminal directly over, load terminal 15 is symmetrically distributed in the both sides of coil 9.

The structure of contact system such as Fig. 1, shown in Figure 3, making one layer insulating 10 on coil 9 insulate the drive coil 9 and the structure on upper strata, and exposes coil electrode 13 and four load terminals 15.Four load terminals 15 are formed electrode system.On coil covering 10, be manufactured with fixed contact 6, bearing 8, torsion beam 11 and rotating shaft 14 successively.Torsion beam 11, bearing 8 and the permalloy layer of rotating shaft 14 for electroplating, become " ten " font structure, cross is centered close to the centre of silicon substrate 5, torsion beam 11 has identical thickness with rotating shaft 14, bearing 8 is connected with rotating shaft 14 two ends, and bearing 8 and fixed contact 6 and rotating shaft 14 thickness differences form the working clearance of relay.The two ends of the torsion beam 11 of two pairs of fixed contact 6 symmetric arrangement, and connect one to one with two pairs of load electrodes 15, its end can contact with fixed contact when torsion beam 11 was rotated.

The operation principle of present embodiment is as follows:

The course of work of bistable relay, on two pairs of fixed contacts, load a load respectively, two drive coil two ends of series connection apply a rectangular pulse, when two coils in series connection apply the pulse of a forward, instantaneous two drive coils produce opposite electromagnetic field, electromagnetic field makes torsion beam magnetize towards a direction, magnetized torsion beam is subjected to a clockwise moment of torsion so under the effect at moment of torsion closing of electromagnetic field and permanent magnetic field in the field, torsion beam turns clockwise around rotating shaft, and then the fixed contact contact on an end of the torsion beam on the left of making and corresponding one side, connect the load of the loading in left side, the left side is in the closure state opposite side and is in off-state and keeps this state by permanent magnet; Otherwise applying reverse pulse at its drive coil is to make torsion beam be subjected to anticlockwise moment of torsion, and then torsion beam is rotated counterclockwise, and right side load conducting is in closure state, and the left side is in off-state, keeps this state by permanent magnet.

The structure of bistable electromagnetic microrelay as shown in Figure 1, the center terminal center of coil and the terminal center of lead must align up and down with the coil core center; About 50 microns of the silicon cup etching residual thickness of making coil magnetic core and iron core.

The contact system structure as shown in Figure 3, the length of torsion beam should surpass about 100 microns in the outside of hub of a spool terminal, can make the suffered driving moment of torsion beam bigger like this; Align with the corresponding fixed contact left and right sides respectively in the left and right sides of torsion beam; Distance between the paired fixed contact is approximately 200 microns.

Claims

1. electromagnetism bistable micro-relay is characterized in that: comprise silicon substrate (5), at magnetic core iron core system, the drive coil system that makes on silicon substrate of the lower surface etching of silicon substrate (5) and the contact system of arranging on drive coil system top;

Described magnetic core iron core system comprises an iron core (7) and two magnetic cores (2), the center of described iron core overlaps with the center of silicon substrate, described two magnetic cores are symmetrically distributed with respect to iron core (7) along the direction of silicon substrate center line, described iron core (7) is leg-of-mutton silicon cup for the lower surface at silicon substrate etches cross sectional shape, on silicon cup, be coated with permalloy layer and form iron core (7), the structure of two magnetic cores (2) is identical with the structure of iron core (7), also connects by permalloy layer between magnetic core (2) and the iron core (7); Below iron core and magnetic core, be provided with the protective layer (3) of insulating effect, below protective layer (3), be fitted with permanent magnet (1);

Described drive coil system comprise two floor plan drive coil (9), connect lead (12) and two pairs of load electrodes (5) of drive coil; Be manufactured with the lead (12) of a connection drive coil (9) at the upper surface of silicon substrate (5), two terminals of lead (12) lay respectively at two coil magnetic cores (2) directly over, whole lead (12) becomes " U " font structure, be manufactured with a layer insulating (10) above the terminal at two that remove lead (12), on insulating barrier (10), be manufactured with two planar coils (9) and two pairs of load terminals (15)), the center terminal of planar coil (9) be in lead (12) terminal directly over, and be conducted with conductor terminal, two pairs of load terminals (15) are symmetrically distributed in the both sides of two drive coils (9) respectively;

Described contact system comprises two pairs of fixed contacts (6), bearing (8), torsion beam (11) and rotating shaft (14); On coil (9), be manufactured with insulating barrier (10), and expose coil electrode (13) and two pairs of load terminals (15), on insulating barrier (10), be manufactured with two pairs of fixed contacts (6), bearing (8), torsion beam (11) and rotating shaft (14), torsion beam (11), bearing (8) and rotating shaft (14) permalloy layer for electroplating, become " ten " font structure, the center of cross structure overlaps with the center of silicon substrate (5), torsion beam (11) has identical thickness with rotating shaft (14), bearing (8) is connected with rotating shaft (14) two ends, bearing (8) and fixed contact (6) and rotating shaft (14) thickness difference form the working clearance of relay, the two ends of the torsion beam (11) of two pairs of fixed contacts (6) symmetric arrangement, and connect one to one with two pairs of load electrodes (15), its end can contact with fixed contact when torsion beam (11) was rotated.