JP2008159326A - Contact switching device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a contact switching device capable of preventing flowing out of a conductive fluid from an injection port. <P>SOLUTION: The contact switching device has the body part 1 which has a housing chamber 1d in which a conductive fluid L is stored and a pair of contacts 5a, 6a are installed and an injection port 2f for injecting the conductive fluid L into the housing chamber 1d. The housing chamber 1d has a hollow part 1a, having a larger volume than other portions and a second channel 1c which is a passage of the conductive fluid L of which one end side is connected to the hollow part 1a and the contacts 5a, 6a are exposed at the other end side; and since the step portion 20 protruding to the lower part in the second channel 1c is formed into a single body with a substrate 2, the height dimension in the vertical direction of the second channel 1c is made smaller than the height dimension in vertical direction of the hollow part 1a. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a contact switching device.

Conventionally, a contact opening / closing device (liquid metal switch) that opens and closes a contact by moving a liquid metal by driving a piezoelectric element has been provided, for example, as disclosed in Patent Document 1. This contact switching device includes a piezoelectric substrate layer having a plurality of contacts exposed to the outside, a plurality of piezoelectric elements connected to the contacts, and a driving device fluid having an inert driving fluid separating each piezoelectric element A tank layer, a thin film layer pressed by a piezoelectric element, a plurality of switch contacts connected to a circuit board, a liquid metal channel layer having a liquid metal and a switching fluid connecting each switch contact, and a switch contact And a circuit board layer having a circuit connected thereto. The operation of the contact switching device will be described below. When a voltage is applied between the pair of contacts of the piezoelectric substrate layer, the piezoelectric element connected to the pair of contacts expands, and the thin film layer is pressed as the piezoelectric element expands. When the thin film layer is pressed, the pressure of the switching fluid in the liquid metal channel layer rises, and the increase in the pressure of the switching fluid breaks the connection between the switch contacts by the liquid metal, and thus on the circuit board layer circuit. The contact of is open. In this contact switching device, when the contact switching device is assembled, the driving fluid is injected into the driving device fluid tank layer from the inlet, and then the driving fluid is filled in the driving device fluid tank layer by sealing the inlet.
JP 2004-319477 A

  By the way, in addition to the contact switching device as described above, a conductive fluid is stored, and a main body having a storage chamber in which a pair of contacts are exposed, and a conductive fluid by partially deforming the main body. There is known a contact opening / closing device provided with an actuator that moves the switch and switches the conduction state between the pair of contacts. However, in such a contact switching device, as in the case of injecting the driving fluid in the conventional example, when the conductive fluid is injected from the inlet into the storage chamber and the inlet is sealed, the conductive fluid is injected. Since the injection port is open until the injection port is sealed, there is a possibility that the conductive fluid in the storage chamber flows backward and flows out of the injection port.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a contact switching apparatus capable of preventing a conductive fluid from flowing out from an inlet.

  In order to achieve the above object, a first aspect of the present invention provides a main body having a storage chamber for storing a conductive fluid and an inlet for injecting the conductive fluid into the storage chamber, and at least a part of the storage chamber. One or a plurality of contacts provided in a state of being exposed to each other, and the conductive fluid is moved by deforming the wall portion of the storage chamber in the thickness direction of the main body portion to move between the contacts through the conductive fluid. Drive means for opening, and the storage chamber has a cavity with a volume larger than that of the other part, a cross-sectional area perpendicular to the moving direction of the conductive fluid is narrower than the cavity, and a cavity on one end side. The channel portion is connected to the other end and the contact point is exposed to the other end, and the height dimension in the thickness direction of the channel portion is smaller than the height dimension in the thickness direction of the cavity portion.

  According to a second aspect of the present invention, in the first aspect of the invention, the main body portion includes a semiconductor substrate and an insulating substrate, and the storage chamber joins the insulating substrate so as to close a groove formed on the semiconductor substrate side. And a step portion protruding in the direction from the insulating substrate toward the semiconductor substrate in the flow path portion is formed integrally with the insulating substrate.

  According to a third aspect of the present invention, in the first aspect of the present invention, the main body portion includes a semiconductor substrate and an insulating substrate, and the storage chamber joins the insulating substrate so as to close a groove formed on the semiconductor substrate side. And a step portion protruding in the direction from the semiconductor substrate toward the insulating substrate in the flow path portion is formed integrally with the semiconductor substrate.

  According to a fourth aspect of the present invention, in the first aspect of the invention, the main body portion includes a semiconductor substrate and an insulating substrate, and the storage chamber joins the insulating substrate so as to close a groove formed on the semiconductor substrate side. The first step portion formed in the flow path portion and projecting in the direction from the semiconductor substrate toward the insulating substrate is formed integrally with the semiconductor substrate, and the second step portion projecting in the direction from the insulating substrate toward the semiconductor substrate is formed. It is formed integrally with an insulating substrate.

  The invention of claim 5 is characterized in that, in the invention of claim 4, the first step portion and the second step portion have different lengths in the moving direction of the conductive fluid.

  According to the invention of claim 1, since the height dimension in the thickness direction of the flow path part is made smaller than the height dimension in the thickness direction of the cavity part, the influence of the surface tension in the flow path part can be increased. Therefore, the surface tension can prevent the conductive fluid from returning to the inlet after the conductive fluid is injected into the storage chamber, and the conductive fluid is prevented from flowing out of the main body from the inlet. be able to.

  According to the invention of claim 2, since the step portion protruding in the direction from the insulating substrate to the semiconductor substrate in the flow path portion is integrally formed with the insulating substrate, the height dimension in the thickness direction of the flow path portion is the cavity portion. Since it is smaller than the height dimension in the thickness direction, the influence of the surface tension in the flow path portion can be increased, so that after the conductive fluid is injected into the storage chamber, the conductive fluid tries to return to the inlet side. Can be suppressed by the surface tension, and the conductive fluid can be prevented from flowing out of the main body from the inlet.

  According to the invention of claim 3, since the step portion protruding in the direction from the semiconductor substrate to the insulating substrate in the flow path portion is formed integrally with the semiconductor substrate, the height dimension in the thickness direction of the flow path portion is the cavity portion. Since it is smaller than the height dimension in the thickness direction, the influence of the surface tension in the flow path portion can be increased, so that after the conductive fluid is injected into the storage chamber, the conductive fluid tries to return to the inlet side. Can be suppressed by the surface tension, and the conductive fluid can be prevented from flowing out of the main body from the inlet.

  According to the invention of claim 4, the first step portion protruding in the direction from the semiconductor substrate toward the insulating substrate in the flow path portion is formed integrally with the semiconductor substrate, and the first step portion protruding in the direction toward the semiconductor substrate from the insulating substrate. Since the second step portion is formed integrally with the insulating substrate, the height dimension in the thickness direction of the flow path portion is smaller than the height dimension in the thickness direction of the cavity portion, so that the influence of the surface tension in the flow path portion is increased. Therefore, it is possible to prevent the conductive fluid from returning to the inlet side after injecting the conductive fluid into the storage chamber by the surface tension, and the conductive fluid flows out of the main body from the inlet. Can be prevented.

  According to the invention of claim 5, since the first step portion and the second step portion are formed so that the length dimension in the moving direction of the conductive fluid is different from each other, the height dimension in the thickness direction of the flow path portion. Is smaller than the height dimension in the thickness direction of the cavity portion, so that the influence of the surface tension in the flow path portion can be increased, so that after the conductive fluid is injected into the storage chamber, the conductive fluid moves to the inlet side. The return can be suppressed by the surface tension, and the conductive fluid can be prevented from flowing out of the main body from the inlet.

  Hereinafter, embodiments of the contact switching device of the present invention will be described with reference to the drawings. However, in the following description, the vertical direction in FIG. In the present embodiment, as shown in FIGS. 1A and 1B, the storage chamber 1d in which the conductive fluid L is stored and the pair of contacts 5a and 6a are exposed, and the storage chamber 1d are electrically conductive. The main body 1 having an injection port 2f for injecting the fluid L, the closing plate 4 for closing the injection port 2f, and the conductive fluid L stored in the storage chamber 1d are moved to move the pair of contacts 5a, 6a. And an actuator 7 which is a driving means for switching between the conductive states. In the present embodiment, a liquid metal (for example, mercury) at normal temperature and normal pressure (25 ° C., 1 atm) is used as the conductive fluid L.

  As shown in FIGS. 1C to 1E, the main body 1 is configured using a substrate 2 and an insulating substrate 3. The substrate 2 is made of, for example, a single crystal silicon substrate, and as shown in FIG. 1 (c), a substantially rectangular recess 2a is provided on the front surface thereof. A recess 2b for the cavity 1a for storing the conductive fluid L is provided on the rear surface of the substrate 2 corresponding to the recess 2a. As shown in FIG. Is formed in a substantially diamond shape. Further, in the substrate 2, the bottom wall portion of the recess 2a is a thin-film diaphragm portion 2c, and a truncated pyramid-shaped projection 2d protruding forward is integrally formed at a substantially central portion of the diaphragm portion 2c. (See FIG. 1C).

  On the rear surface of the substrate 2, on the one end side of the recess 2b (the right end side in FIG. 1B), the first groove portion for the first channel 1b serving as a passage for injecting the conductive fluid L into the cavity portion 1a. 2e is formed. The first groove 2e is formed in a substantially rectangular shape, and communicates with the front side of the substrate 2 through a substantially square inlet 2f (see FIG. 1C). The injection port 2f is provided to inject the conductive fluid L into the first channel 1b, and is closed by the closing plate 4 made of a substantially rectangular glass plate after the conductive fluid L is injected (see FIG. 1 (a)).

  On the other hand, on the other end side of the recess 2b on the rear surface of the substrate 2 (the left end side in FIG. 1B), a substantially U-shaped first channel for the second channel 1c serving as a flow path through which the conductive fluid L moves. Two groove portions 2g are formed. Further, as shown in FIG. 1C, a step portion 20 that protrudes downward from the upper surface of the second groove portion 2 g is formed integrally with the substrate 2.

  The concave portion 2a, the concave portion 2b, the protruding portion 2d, the groove portions 2e and 2g, the injection port 2f, and the step portion 20 are formed on the substrate 2 using a semiconductor manufacturing process such as ICP (Inductively Coupled Plasma) etching. However, since the semiconductor manufacturing process as described above is well known, detailed description thereof is omitted here. Further, instead of the substrate 2, an insulating resin substrate formed in the same shape as the substrate 2 may be used.

  The insulating substrate 3 is made of, for example, a transparent glass substrate having substantially the same outer dimensions as the substrate 2 and is bonded to the rear surface of the substrate 2 by anodic bonding or the like. In addition to the glass substrate, an insulating resin substrate may be used as the insulating substrate 3.

  By thus bonding the insulating substrate 3 to the rear surface of the substrate 2, the rear surface openings of the recess 2b, the first groove portion 2e, and the second groove portion 2g are respectively closed. Then, the recess 2b whose rear opening is closed by the insulating substrate 3 serves as a cavity 1a for accommodating the conductive fluid L, and the first groove 2e whose rear opening is closed by the insulating substrate 3 serves as the conductive fluid L. As the first channel 1b for injecting into the cavity 1a, the second groove 2g whose rear opening is closed by the insulating substrate 3 is used as the second channel 1c serving as the flow path of the conductive fluid L, respectively. A storage chamber 1d in which the conductive fluid L is movably stored is constituted by the portion 1a, the first channel 1b, and the second channel 1c.

  Here, since the step portion 20 is formed integrally with the substrate 2 in the second groove portion 2g, the vertical dimension of the second channel 1c is higher than the vertical dimension of the cavity portion 1a. It is smaller (see FIG. 1 (c)).

  On the other hand, in the insulating substrate 3, four through holes 3 a are formed through a portion of the substrate 2 that faces the second groove 2 g, that is, a portion that becomes the bottom surface of the second channel 1 c. (See FIGS. 1B and 1D). Contact points 5a and 6a made of a plating layer using a conductive metal material are alternately formed on the inner peripheral surface and the front opening of each of the four through holes 3a. When joined to 2, each pair of contacts 5a, 6a is exposed in the second channel 1c. As the conductive metal material for each contact 5a, 6a, it is preferable to use a material (for example, solder) that has good wettability with respect to the conductive fluid L.

  A pair of electrode pads 5b and 6b using a conductive metal material such as copper are formed on the rear surface of the insulating substrate 3, and the electrode pad 5b is connected to the pair of contacts 5a by the wiring pattern 5c. 6b is connected to a pair of contacts 6a by a wiring pattern 6c.

  By the way, although the two contacts 5a are provided as described above, after the conductive fluid L is injected into the storage chamber 1d, only one of them is left and the other contact 5a is connected to the electrode pad 5b. Electrically disconnected. This also applies to the contact point 6a, and this makes it possible to cope with variations in the injection amount of the conductive fluid L. For example, when the amount of the conductive fluid L injected is small and the conductive fluid L is not in contact with any of the contacts 5a and 6a, the amount of the conductive fluid L injected is large and the conductive fluid L contacts only the contact 5a. In the former case, the contacts 5a, 6a on the other end side (the right side in FIG. 1 (b)), which is the back side of the second channel 1c, are different from each other. The electrode 5b is cut from the electrode pads 5b and 6b. In the latter case, the contact 5a on one end side (the left side in FIG. 1B) on the front side of the second channel 1c is cut from the electrode pad 5b and the second The contact 6a on the back side of the channel 1c is cut from the electrode pad 6b. By doing in this way, the stable opening / closing performance can be exhibited irrespective of the variation in the injection amount of the conductive fluid L.

  The actuator 7 is made of, for example, a piezoelectric vibrator formed in a flat rod shape, and is a cantilever joined to the front surface of the substrate 2 in such a manner that the tip portion is opposed to the recess 2a and at the same time is brought into contact with the tip of the projection 2d. It has a structure. Thus, when a voltage is applied in the thickness direction of the actuator 7, the tip of the unfixed actuator 7 bends in a direction approaching the diaphragm portion 2 c and presses the protrusion 2 d, thereby the diaphragm portion 2 c of the substrate 2. Will be deformed (flexed) toward the recess 2b. When the application of the voltage is stopped, the actuator 7 does not press the protrusion 2 and the diaphragm portion 2c is restored to the original state.

  Next, the operation of this embodiment will be described. First, in a state where no voltage is applied, the actuator 7 does not operate, so that the diaphragm portion 2c is not deformed. At this time, the conductive fluid L stored in the storage chamber 1d is not in contact with any of the contacts 5a and 6a, and the contacts 5a and 6a are insulated (opened) (off state).

  When a voltage is applied from this OFF state to drive the actuator 7, the tip of the actuator 7 presses the protrusion 2d, and thereby the diaphragm 2c is pushed backward. When the diaphragm portion 2c is pushed down, the volume of the cavity portion 1a is reduced, whereby the conductive fluid L accommodated in the cavity portion 1a is moved to the second channel 1c side, and the pair of contacts 5a and 6a are moved. Short-circuited (closed) by the conductive fluid L (ON state).

  When the application of voltage is stopped from this on state, the diaphragm portion 2c deformed by the actuator 7 returns to the original state. Along with this, the volume of the cavity 1a returns to the original, so that the conductive fluid L that has moved to the second channel 1c side returns to the cavity 1a side, and the pair of contacts 5a and 6a are opened (OFF state). ).

  Hereinafter, a method for injecting the conductive fluid L into the storage chamber 1d will be described with reference to the drawings. First, the main body portion 1 is disposed in a vacuum chamber 8 having a fluid tank 8a in which the conductive fluid L is stored, and the vacuum chamber 8 is evacuated using a vacuum pump (not shown), whereby a vacuum chamber is obtained. 8 and the storage chamber 1d of the main body 1 are depressurized to a predetermined degree of vacuum (see FIG. 2A). Next, the main body 1 is immersed in the fluid tank 8a (see FIG. 2B), and a vacuum chamber is obtained. When the pressure in the chamber 8 is increased, the pressure in the vacuum chamber 8 becomes larger than the pressure in the storage chamber 1d, so that the conductive fluid L stored in the fluid tank 8a enters the storage chamber 1d from the inlet 2f. It penetrates (see FIG. 2 (c)). Then, after increasing the pressure in the vacuum chamber 8 until a predetermined conductive fluid L is injected into the storage chamber 1d (see FIG. 2D), the main body 1 is taken out from the fluid tank 8a, and the blocking plate 4 Is bonded to the front surface of the substrate 2 to close the injection port 2f, whereby the step of injecting the conductive fluid L into the storage chamber 1d is completed. When the main body 1 is immersed in the fluid tank 8a, the conductive fluid L also enters the recess 2a. However, the conductive fluid L accumulated in the recess 2a is removed after the inlet 2f is closed by the closing plate 4. Therefore, illustration of the conductive fluid L that accumulates in the recess 2a is omitted here.

  Here, in the present embodiment, as described above, the step portion 20 is formed integrally with the substrate 2 in the second groove portion 2g, so that the height dimension of the second channel 1c in the vertical direction is set to the height in the vertical direction of the cavity portion 1a. It is smaller than the size. For this reason, since the influence of the surface tension in the second channel 1c can be increased as compared with the hollow portion 1a, the conductive fluid L moves toward the inlet 2f after the conductive fluid L is injected into the storage chamber 1d. The return can be suppressed by the surface tension, and the conductive fluid L can be prevented from flowing out of the main body 1 from the inlet 2f.

  In addition, when the height of the second channel 1c in the vertical direction is reduced, the conductive fluid L pushed out from the cavity 1a does not reduce the height when the actuator 7 deflects the diaphragm 2c. Compared with the second channel 1c, it can move largely.

  Instead of forming the step portion 20 integrally with the substrate 2 as described above, as shown in FIG. 3A, a step portion 30 protruding upward from the upper surface of the insulating substrate 3 in the second channel 1c is formed. In this case, the height of the second channel 1c in the vertical direction is smaller than the height in the vertical direction of the cavity 1a. Therefore, the same effect as described above can be obtained. Further, as shown in FIG. 3B, step portions 20 and 30 may be provided on both the substrate 2 and the insulating substrate 3 in the second channel 1c, and further, as shown in FIG. 3C. In the second channel 1c, the length dimension of the step portion 30 in the moving direction of the conductive fluid L (left and right direction in FIG. 3C) may be larger than the length dimension of the step portion 20 in the left and right direction. Absent. Also in these cases, the height dimension in the vertical direction of the second channel 1c can be made smaller than the height dimension in the vertical direction of the cavity portion 1a as in the case where the step portion 20 is provided. There is an effect.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the contact switching device of embodiment of this invention, (a) is a schematic front view, (b) is a schematic rear view, (c) is a sectional view on the AA 'line | wire, (d) Is a sectional view taken along the line BB ', and (e) is a sectional view taken along the line CC'. It is a figure which shows the injection | pouring method of a conductive fluid same as the above, (a) is a figure which shows before immersing a main-body part in a conductive fluid, (b) is a figure which shows immediately after immersing a main-body part in a conductive fluid, (C) is a figure which shows the case where the pressure in a chamber is raised, (d) is a figure which shows the case where the pressure in a chamber is raised to a predetermined value. It is a figure which shows another structure same as the above, (a) is sectional drawing which shows the case where a step part is provided in an insulated substrate, (b) is a cross section which shows the case where a step part is provided in both a board | substrate and an insulated substrate FIG. 4C is a cross-sectional view showing a case where the length of the step provided on the substrate is different from that of the step provided on the insulating substrate.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Main-body part 1a Cavity part 1c 2nd channel (flow-path part)
1d Storage room 20 Step part 2c Diaphragm part (wall part)
2f Inlet 5a, 6a Contact 7 Actuator (drive means)
L Conductive fluid

Claims (5)

  A storage chamber in which the conductive fluid is stored, a main body having an inlet for injecting the conductive fluid into the storage chamber, and one or more contacts provided in a state where at least a part thereof faces the storage chamber; Drive means for conducting or opening between the contacts via the conductive fluid by moving the conductive fluid by deforming the wall of the storage chamber in the thickness direction of the main body, and A hollow portion having a volume larger than that of the portion, and a flow path portion in which an area of a cross section perpendicular to the moving direction of the conductive fluid is smaller than that of the hollow portion and is connected to the hollow portion on one end side and the contact is exposed on the other end side A contact opening / closing device characterized in that the height dimension in the thickness direction of the flow path portion is smaller than the height dimension in the thickness direction of the cavity portion.   The main body portion includes a semiconductor substrate and an insulating substrate, and the storage chamber is formed by bonding the insulating substrate so as to close a groove formed on the semiconductor substrate side. 2. The contact switching device according to claim 1, wherein a stepped portion projecting in a direction toward is integrally formed on the insulating substrate.   The main body portion includes a semiconductor substrate and an insulating substrate, and the storage chamber is formed by bonding the insulating substrate so as to close a groove formed on the semiconductor substrate side, and the insulating substrate is separated from the semiconductor substrate in the flow path portion. 2. The contact switching device according to claim 1, wherein a stepped portion projecting in a direction toward is formed integrally with the semiconductor substrate.   The main body portion includes a semiconductor substrate and an insulating substrate, and the storage chamber is formed by bonding the insulating substrate so as to close a groove formed on the semiconductor substrate side, and the insulating substrate is separated from the semiconductor substrate in the flow path portion. The first step portion protruding in the direction toward the semiconductor substrate is integrally formed on the semiconductor substrate, and the second step portion protruding in the direction from the insulating substrate toward the semiconductor substrate is formed integrally on the insulating substrate. Item 1. The contact switching apparatus according to Item 1.   The contact switching device according to claim 4, wherein the first step portion and the second step portion have different lengths in the moving direction of the conductive fluid.

Images