JPH05242788A - Electrostatic relay - Google Patents

Abstract

PURPOSE:To provide an electrostatic relay having fixed base bodies set on both sides of a movable plate, in which deformation caused by thermal expansion is hard to be generated, unbalance between the sizes of the upper and lower base bodies can be diminished, and moreover, connecting electrodes for leading to an outer circuit can be easily formed. CONSTITUTION:A pair of fixed base bodies 7, 8 and a movable plate 6 are formed of conductive base boards, and connecting electrodes 74, 84 for electrically connecting fixed side driving electrodes 70, 80 to an outer circuit, are set on the surfaces of the fixed base bodies 7, 8, opposite to the fixed side driving electrodes 70, 80. The connecting electrodes 74, 84 and fixed driving side electrodes 70, 80 are mutually conducted through fixed base bodies 7, 8 formed of the conductive base boards.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic relay that contacts and separates contacts by utilizing electrostatic force (Coulomb force).

[0002]

2. Description of the Related Art FIG. 3 shows a conventional electrostatic relay. This electrostatic relay includes fixed contacts 171, 171 and a fixed-side drive electrode 172 having a symmetrical structure on the left and right surfaces of the fixed base 161.
172, and the spacer 1 on the fixed base 161.
A support frame 160 is attached with 74 in between, and a movable plate 162 that is connected to the support frame 160 at support portions 165 on both sides of the center and extends in the left-right direction at the central opening of the support frame 160,
162, and the movable plates 162, 162 themselves are movable side drive electrodes. Movable contacts 173 and 173 are provided on the lower surface of the movable plate 162. Fixed side drive electrode 1
If an electrostatic force is applied between the movable plates 162, 162 and the movable plates 162, 162, that is, the movable plates 162, 162.
The tip end side of 62 bends and swivels downward with the support portion 165 as a base point, and fixed contacts 171 and 171 and movable contacts 173 and 173.
Come into contact.

The electrostatic relay shown in FIG. 4 has an electrostatic force increased when a drive voltage is applied, as compared with the conventional example. This electrostatic relay has the same basic structure as the above-mentioned conventional example, but fixed bases 161 and 167 are provided above and below the support frame 160 of the movable plate 162, respectively, and movable by the fixed bases 161 and 167. A voltage is applied between the fixed side drive electrodes 172 and 172 provided on the fixed bases 161 and 167 on both sides of the plate 162 and the movable plate 160 to apply an electrostatic force to operate the movable plate 160. As a result, the fixed contacts 171 and 1 of the fixed bases 161 and 167 are formed.
The movable contacts 173, 173 formed on both surfaces of the movable plate 162 come into contact with any one of 71 to perform a relay operation. Fixed-side drive electrode 17 of the fixed substrates 161 and 167
The surfaces of 2, 172 are covered with insulating films 175, 175. The fixed-side drive electrodes 172, 172 are extended along the joint surface of the movable plate 162 with the support frame 160, respectively, and are exposed on the surface of the support frame 160 or the surface of the fixed base 161. The connection electrodes 174 and 176 are electrically connected to an external circuit. Further, since the movable plate 162, which is the movable side drive electrode, is electrically connected to an external circuit, a connection electrode 175 for the movable side drive electrode is formed on the surface of the support frame 160 outside the connection electrode 174. ..

In this electrostatic relay, since the fixed-side drive electrodes 172 and 172 are arranged on both sides of the movable plate 162 which is the movable-side drive electrode, the electrostatic force applied to the movable plate 162, that is, the driving force is increased, so that the movable relay can be securely operated. Moreover, it has an advantage that a quick relay operation can be performed.

[0005]

However, in the above-described conventional electrostatic relay having a structure in which fixed side drive electrodes are arranged on both sides of the movable side drive electrode, the entire relay is distorted by thermal expansion during use, resulting in operation failure. There is a problem that it causes trouble. This is because the conventional electrostatic relay uses a conductive substrate made of silicon or the like for the movable plate 162 that serves as the movable side drive electrode and the support frame 160, whereas the fixed base 161
An insulating substrate is used for 167, and the movable plate 162 and the fixed bases 161 and 167 have different thermal expansion characteristics. Therefore, if a temperature change occurs when using the electrostatic relay,
Due to the difference in the coefficient of thermal expansion between the fixed base bodies 161, 167 and the movable plate 6 and the support frame 60, the entire relay is distorted. Due to its structure, the electrostatic relay has fixed contacts 171, 17
Since there is only a slight gap between the No. 1 and the movable contacts 173, 173, the distortion as described above has a great influence on the operation of the electrostatic relay.

Further, since it is necessary to provide the connection electrodes 174 to 176, an imbalance occurs in the shapes of the upper and lower fixed bases 161 and 167, the electrostatic force is reduced, and the electrode bonding structure becomes complicated, resulting in a continuous structure. There is also a problem that reliability such as energization decreases. First, the lower fixed base 16
In order to provide the connection electrode 176 on the upper surface of No. 1, the movable plate 162
It is necessary to make the supporting frame 160 smaller than the fixed base 161 to provide an exposed surface on the upper surface of the fixed base 161. Next, in order to provide the connection electrode 174 on the upper fixed base 167, the fixed base 167 is provided rather than the support frame 160 of the movable plate 162.
Must be reduced to provide an exposed surface on the surface of the support frame 160 on which the connection electrode 174 of the fixed base 167 is arranged. Moreover, on the surface of the support frame 160, the connection electrode 175 for the movable side drive electrode is also provided. As a result, the upper fixed base 167 is significantly smaller than the lower fixed base 161. Since the smallest effective fixed base 167 is used as a reference for the substantial effective area related to the operating characteristics of the electrostatic relay, the effective area of the electrostatic relay becomes smaller than the required external dimensions, and It has been a factor that hinders miniaturization or higher performance.

Further, the electric path connected to the connection electrodes 174 and 176 needs to be extended to the outside through the joint surface between the fixed base bodies 161 and 167 and the support frame 160, but such a metal joint portion is involved. The formation of the electric path is technically difficult, and the reliability of continuous energization is reduced. Therefore,
As described above, an object of the present invention is to solve the problems of the prior art in an electrostatic relay having a structure in which fixed bases are arranged on both sides of a movable plate, and it is difficult for distortion due to thermal expansion to occur. An object of the present invention is to provide an electrostatic relay having a structure in which the imbalance of the size of the fixed substrate can be reduced, and further, a connection electrode for connecting to an external circuit can be easily formed.

[0008]

In the electrostatic relay according to the present invention for solving the above problems, a pair of fixed bases having fixed contacts and fixed side drive electrodes have movable contacts and movable side drive electrodes on both sides. In an electrostatic relay in which the movable plate is sandwiched from both sides and the movable side drive electrode and the fixed side drive electrode on the outside face each other, a pair of fixed base and movable plate are made of a conductive substrate, and the fixed side drive The connection electrode for electrically connecting the electrode and the external circuit is provided on the surface of the fixed base opposite to the fixed drive electrode, and the connection electrode and the fixed drive electrode are provided via the fixed base made of a conductive substrate. Is conducted.

The basic structure of the electrostatic relay such as the movable plate and the fixed substrate may be the same as that of a normal electrostatic relay in which the fixed substrate is arranged on both sides of the movable plate. For example, the fixed contact provided on the fixed substrate, the fixed-side drive electrode, and the movable contact of the movable plate have the same arrangement shape as the conventional electrostatic relay.
It can be set freely. Electrostatic force can be increased by providing an electret on the surface of the movable plate serving as the movable side drive electrode or the surface of the fixed side drive electrode. In particular, if the fixed-side drive electrodes on both sides are provided with electrets having different polarities, one electret gives a suction force to the movable-side drive electrode, and the electret on the opposite side gives a repulsive force to the movable-side drive electrode. As a result, the upper and lower electrets exert a force in the same direction, resulting in a large increase in electrostatic force, which is preferable.

In the present invention, both the movable plate and the pair of fixed bases are made of a conductive substrate such as a silicon substrate. Therefore, in order to form a conductive structure such as a fixed contact on the fixed base, it is necessary to form an insulating layer on the surface of the fixed base made of a conductive substrate and then form the fixed contact or the like on the insulating layer. In addition, when the fixed side drive electrode is formed on the fixed base or when the fixed side drive electrode is joined to the support frame of the movable plate, an insulating layer is formed at a portion where insulation is required.

In order to apply a voltage to the fixed side drive electrode to generate an electrostatic force, a connection electrode for electrically connecting the fixed side drive electrode to an external circuit is required. This connection electrode,
It is provided on the surface of the fixed base opposite to the fixed drive electrode. That is, the connection electrode is provided not on the surface of the fixed base body that is joined to the movable plate or the support frame of the movable plate, but on the opposite surface thereof. The connection electrode is directly formed on the surface of the fixed base made of a conductive substrate, and is electrically connected to the fixed side drive electrode through the fixed base. The connection electrode may be provided at any place on the surface of the fixed substrate.

For the connection electrode, in addition to the method of forming an electrode layer on the surface of the fixed substrate using a material different from that of the solid substrate, a high concentration impurity layer is formed on the fixed substrate made of a conductive substrate such as silicon. As a result, the internal structure of the solid substrate itself can have a function as an electrode.

[0013]

If both the movable plate and the pair of fixed bases are made of a conductive substrate, the thermal expansion characteristics of the movable plate and the fixed base are almost the same, so that distortion due to the difference in the coefficient of thermal expansion occurs. Will not do. Next, if a connection electrode is provided on the surface of the fixed base opposite to the fixed-side drive electrode, the fixed base has conductivity, so that the connection electrode and the fixed-side drive are connected via this fixed base. The electrodes can be electrically connected.

As a result, the problem of the above-mentioned conventional electrostatic relay, that is, in the upper and lower fixed bases with the movable plate sandwiched therebetween,
This solves the problem that the upper and lower fixed bases must be greatly different in size to occupy the installation place of the connection electrodes. Since the connection electrode is provided on the open surface of the fixed base opposite to the joint surface with the movable plate, it is not necessary to make a large difference in size between the upper and lower fixed bases. Further, since the electric path structure connecting the connection electrode and the fixed side drive electrode is not affected by the joint structure of the fixed base body, the movable plate and the support frame at all, the production is easy and the reliability of the connection is remarkably improved. ..

In particular, in the lower fixed base body, for example, the connection electrodes provided on the lower surface of the fixed base body can be directly connected to the external circuit via the package mounting support on which the electrostatic relay is mounted. And simplification of connection work,
The connection distance can be shortened and the connection reliability can be improved.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a sectional structure of an electrostatic relay according to the present invention, and FIG. 2 shows a planar structure. In the electrostatic relay, the movable plate 6 and the support frame 60 that supports the movable plate 6 are sandwiched between the upper and lower fixed bases 7 and 8 to be integrally joined. The movable plate 6, the support frame 60, and the fixed bases 7 and 8 are formed of a silicon single crystal plate. Specifically, after a plurality of movable plates 6 and support frames 60 and a plurality of upper and lower fixed bases 7 and 8 are formed on three silicon wafers, these silicon wafers are stacked and bonded, and then each It is a high productivity and a preferable method to divide | segment into each electrostatic relay part and to manufacture many electrostatic relays simultaneously.

As shown in FIG. 2, a substantially U-shaped groove 61 is formed through the support frame 60, and the inside of the U-shaped groove 61 serves as a rectangular movable plate 6. The movable plate 6 is a support frame 6 around the movable plate 6.
The thickness is smaller than 0, and one side of the movable plate 6 is flexibly supported by the support frame 60. Insulating layers 61, 61 made of a silicon oxide film or the like are formed on both surfaces of the movable plate 6. The insulating layer 61,
On top of 61, movable contacts 62, 6 made of a conductive metal layer or the like.
Two are provided.

An insulating layer 81 is formed on the upper surface of the lower fixed substrate 8, and a fixed contact 82 and a fixed side drive electrode 80 are provided on the insulating layer 81. The fixed-side drive electrode 80 is made of a conductive metal layer or the like, and is joined to the fixed base 8 through a penetrating portion formed in a part of the insulating layer 81. An electret 86 is formed on the surface of the fixed-side drive electrode 80. The entire lower surface of the fixed substrate 8 serves as a connection electrode 84, which is joined on the package mounting support 9 and connected to an external circuit at an arbitrary position.

The upper fixed base 7 has a fixed base 8 on the lower surface.
An insulating layer 81, a fixed contact 72, a fixed side drive electrode 70, and an electret 76 are provided in the same manner as in. However, the electret 76 and the electret 86 of the fixed base body 8 have polarities opposite to each other. As shown in FIG. 2, on the upper surface of the fixed base 7, connection electrodes 74 are formed at one corner.

As shown in FIG. 2, a notch 67 is formed in the support frame 60 of the movable plate 6 arranged on the fixed base 8 so that a part of the fixed contact 82 of the fixed base 8 is exposed. Has been done. The fixed base 8 and the support frame 60 of the movable plate 6 are integrally joined to the fixed contact 82 via a joining layer 89 made of metal or the like. The upper fixed base 7 and the support frame 60 are
It is integrally joined to the fixed contact 72 via the connection electrode 64 for the movable plate 6. A notch 77 is formed in the fixed base 7 so that a part of the fixed contact 72 is exposed. The fixed contact 72 extended above the support frame 60 is exposed at the notch 77. It can be connected to an external circuit. Further, the fixed base 7 is also formed with a notch 78 at a position corresponding to the connection electrode 64 of the movable plate 6, and a part of the connection electrode 64 is exposed.

In the electrostatic relay having the above structure,
When a voltage is applied between the connection electrodes 74 and 84 and the connection electrode 64, as shown by the dotted arrow in FIG.
And the fixed side drive electrode 7 that is electrically connected to the fixed base 7 through the fixed base 7.
A voltage is applied between 0 and the fixed side drive electrode 80 which is electrically connected to the connection electrode 84 via the fixed base body 8 and the movable plate 6 which is the movable side drive electrode. The tip end side of the movable plate 6 is operated upward or downward by the electrostatic force acting between the fixed side drive electrodes 70 and 80 and the movable plate 6 which face each other.
As a result, one of the movable contacts 62, 62 above or below the movable plate 6
Contacts the fixed contacts 71, 71 or 81, 81 to cause a short circuit. That is, the fixed contacts 71, 71 or 81,
One of the external loads connected to 81 is turned on. If the polarity of the input voltage applied between the connection electrodes 74 and 84 and the connection electrode 64 is reversed, the movable plate 6 operates in the opposite direction, and the on / off state of the external load can be reversed.

In the above-mentioned embodiment, the lower fixed base 8, the support frame 60 of the movable plate 6 and the upper fixed base 7 have the same plane dimensions, and the lower electrodes are exposed only at the portions where they need to be exposed. , Small cutouts 67, 77, 78 are formed. Therefore, the substantial area that affects the basic operation and characteristics of the electrostatic relay is the same for both the upper and lower fixed bases 7 and 8 and the movable plate 6, and the movable plate 6 operates upward and downward. The characteristics do not sometimes become unbalanced.

[0023]

As described above, in the electrostatic relay according to the present invention, since the conductive substrate is used as the material of the fixed base which has conventionally been the insulating substrate, the movable plate made of the same conductive substrate is used. There is no difference in the coefficient of thermal expansion between and, and the occurrence of strain due to the difference in the coefficient of thermal expansion is eliminated.

In addition, the connection electrode necessary for connecting the fixed side drive electrode to the external circuit is formed on the surface opposite to the surface facing the movable plate, and the fixed base body made of a conductive substrate is interposed therebetween. Since it can be electrically connected to the fixed-side drive electrode, the connection electrode can be easily formed and its electrical characteristics can be improved. If the connection electrode of the fixed base does not have to be formed on the surface facing the movable plate, the size is reduced in order from the lower fixed base to the support frame of the movable plate and the upper fixed base, and fixed. It is not necessary to secure a place for exposing the connection electrode on the facing surface of the base and the movable plate, and the size and shape of the support frame of each fixed base and the movable plate can be set to be substantially the same. As a result, it is possible to eliminate the imbalance of the operation due to the difference in the areas of the upper and lower fixed bases, improve the operating characteristics of the electrostatic relay, and reduce the size of the electrostatic relay as a whole.

[Brief description of drawings]

FIG. 1 is a sectional view of an electrostatic relay according to an embodiment of the present invention.

FIG. 2 is a plan view of the above.

FIG. 3 is an exploded perspective view of a conventional example.

FIG. 4 is a sectional view of another conventional example.

[Explanation of symbols]

 6 movable plate 60 support frame 62 movable contact 64 connection electrode (movable side) 7, 8 fixed base 70, 80 fixed side drive electrode 72, 82 fixed contact 74, 84 connection electrode (fixed side)

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[Procedure amendment]

[Submission date] May 2, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0012

[Correction method] Change

[Correction content]

[0012] The connection electrode, the surface of the fixed base, the other method is the fixed base to form an electrode layer of a different material, the fixing substrate made of a conductive substrate such as silicon, forming a high concentration impurity layer by, the internal structure itself of the fixed substrate, it is possible to provide a function as an electrode.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Koichi Aizawa Koichi Aizawa 1048, Kadoma, Kadoma, Osaka Prefecture Matsushita Electric Works Co., Ltd. (72) Inventor, Takayoshi Awai, 1048, Kadoma, Kadoma City, Osaka (72) Inventor Takuro Ishida 1048 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Works Co., Ltd. (72) Keiji Kakite 1048 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Works Co., Ltd. (72) Inventor Hideki 1048 Kadoma, Kadoma, Osaka Prefecture Matsushita Electric Works Co., Ltd.

Claims (1)

[Claims] 1. A pair of fixed bases having a fixed contact and a fixed side drive electrode sandwich a movable plate having a movable contact and a movable side drive electrode on both sides from both sides, and a movable side drive electrode and a fixed side drive electrode on the outside thereof. In the electrostatic relay arranged so as to face each other, the pair of fixed base and the movable plate are made of a conductive substrate, and the connection electrode for electrically connecting the fixed side drive electrode and the external circuit is fixed to the fixed base. An electrostatic relay characterized in that a connection electrode and a fixed-side drive electrode are electrically connected to each other via a fixed base body made of a conductive substrate provided on a surface opposite to a side-drive electrode.