JP2008159327A - Contact switching device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a contact switching device capable of preventing adhesion of a surplus conductive fluid, in the surrounding of an injection port. <P>SOLUTION: The contact switching device is provided with the body part 1 which has a housing chamber 1d in which a conductive fluid L is stored and a pair of contacts are installed and an injection groove part 20 which is connected to the housing chamber 1d on one end side and has an injection port 2f for injecting the conductive fluid L into the housing chamber 1d on the other end side, a closing plate 4 for closing the injection port 2f, and an actuator 7 which is a drive means for moving the conductive fluid L stored in the housing chamber 1d and switches the conduction status between the pair of contacts 5a, 6a. A projected wall part 21, which protrudes inside and has a projection face 21a substantially in parallel to the injection port 2f opposed to it is formed with a prescribed spacing from the injection port 2f in the thickness direction of the body part 1, on the inner wall of the injection groove part 20. <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 the driving fluid injection in the conventional example, if the injection port is sealed after the conductive fluid is injected from the injection port into the storage chamber, excess conductive material is formed around the injection port. There has been a problem that it becomes difficult to seal the injection port due to adhesion of the ionic fluid.

  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 device that can prevent an excessive conductive fluid from adhering around the inlet.

  In order to achieve the above object, the invention according to claim 1 is a storage chamber for storing the conductive fluid and a note for injecting the conductive fluid into the storage chamber at the other end while being connected to the storage chamber at one end. A main body having an inlet groove provided with an inlet, one or more contacts provided with at least a portion facing the storage chamber, and a wall of the storage chamber in the thickness direction of the main body being deformed. Driving means for conducting or opening between the contacts via the conductive fluid by moving the conductive fluid, and the injection groove protrudes inward from the inner wall and faces the injection port. A protruding wall portion having a surface is provided at a predetermined interval from the injection port in the thickness direction of the main body portion.

  The invention of claim 2 is characterized in that, in the invention of claim 1, the protruding wall portion is formed of a rough surface having fine irregularities on the protruding surface facing the injection port.

  A third aspect of the invention is characterized in that, in the first aspect of the invention, the projecting wall portion is formed with a coating of a water-repellent material having water repellency on the projecting surface facing the injection port.

  According to the first aspect of the present invention, the protruding wall portion that protrudes inward from the inner wall of the injection groove and has a substantially parallel protruding surface facing the injection port is spaced from the injection port in the thickness direction of the main body. Since the conductive fluid is injected into the storage chamber, the conductive fluid is injected up to the projecting surface of the projecting wall portion, so that an extra conductive fluid may adhere to the periphery of the injection port spaced a predetermined distance from the projecting surface. Therefore, the operation of closing the injection port can be easily performed.

  According to the second aspect of the present invention, since the projecting surface of the projecting wall portion is a rough surface having fine irregularities, the conductive fluid is difficult to adhere to the projecting surface, and therefore excess conductive fluid is easily removed. can do.

  According to the invention of claim 3, since the coating film of the water-repellent material having water repellency is formed on the projecting surface of the projecting wall portion, it becomes difficult for the conductive fluid to adhere to the projecting surface. Can be removed.

  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 this embodiment, as shown in FIGS. 1A and 1B, a storage chamber 1d in which a conductive fluid L is stored and a pair of contact points 5a and 6a are exposed, and a storage chamber 1d on one end side, A main body 1 having an injection groove 20 provided with an injection port 2f for connecting and injecting the conductive fluid L into the storage chamber 1d at the other end, and a closing plate 4 for closing the injection port 2f; An actuator 7 is provided as a driving means for moving the conductive fluid L stored in the storage chamber 1d and switching the conduction state between the pair of contacts 5a and 6a. 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 portion 2 e is formed in a substantially rectangular shape and communicates with the lower end portion of the substantially truncated pyramid-shaped injection groove portion 20 penetrating in the thickness direction of the substrate 2. Further, the upper end of the injection groove 20 communicates with a substantially square injection port 2f on the front surface of the substrate 2 (see FIG. 1C). The injection port 2f is provided for injecting the conductive fluid L into the first channel 1b through the injection groove 20, and is a blocking plate made of a substantially rectangular glass plate after the conductive fluid L is injected. 4 (see FIG. 1A).

  As shown in FIG. 1C, a projecting wall portion 21 having a substantially triangular cross section projecting inwardly protrudes from the inner wall of the injecting groove portion 20 in the circumferential direction. The upper surface of the projecting wall portion 21 is a projecting surface 21a substantially parallel to the injection port 2f, and the projecting surface 21a and the injection port 2f are spaced apart from each other in a vertical direction. Further, the portion surrounded by the projecting surface 21a is a substantially square through hole 21b communicating with the first groove 2e, and the conductive fluid L passes through the through hole 21b from the inlet 2f into the storage chamber 1d. It is supposed to be injected into. The lower portion of the protruding wall portion 21 is an inclined portion whose opening area increases from the through hole 21b toward the storage chamber 1d, and the conductive fluid L flows backward from the storage chamber 1d toward the through hole 21b. To prevent it.

  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.

  The recess 2a, the recess 2b, the protrusion 2d, the grooves 2e and 2g, the injection groove 20 and the protrusion wall 21 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.

  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 this embodiment, since the projecting wall portion 21 is provided in the injecting groove portion 20, as shown in FIG. 3, the projecting surface of the projecting wall portion 21 when injecting the conductive fluid L into the storage chamber 1d. If the conductive fluid L is injected up to 21a, it is possible to prevent the conductive fluid L from adhering to the inner wall between the projecting surface 21a of the injection groove 20 and the injection port 2f. Thus, by preventing the conductive fluid L from adhering to the periphery of the inlet 2f, the operation of closing the inlet 2f with the closing plate 4 can be easily performed.

  Note that a film made of a material having water repellency such as a fluororesin may be formed on the projecting surface 21a of the present embodiment. In this case, when injecting the conductive fluid L into the storage chamber 1d, The conductive fluid L can be prevented from adhering to the projecting surface 21a, and the excess conductive fluid L can be easily removed. Further, any other configuration may be used as long as it can prevent the conductive fluid L from adhering to the projecting surface 21a. Instead of forming a film with a water repellent material as described above, for example, by sandblasting. The protruding surface 21a may be roughened by forming fine irregularities.

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 partial enlarged view of a main-body part cross section same as the above.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Main-body part 1d Storage chamber 20 Injection groove part 21 Projection wall part 21a Projection surface 2c Diaphragm part (wall part)
2f Inlet 5a, 6a Contact 7 Actuator (drive means)
L Conductive fluid

Claims (3)

  A main body having a storage chamber in which a conductive fluid is stored, an injection groove provided with an inlet for connecting the storage fluid to the storage chamber on one end side and injecting the conductive fluid into the storage chamber on the other end; Conductive fluid between one or a plurality of contacts provided with a part facing the storage chamber and the contacts by moving the conductive fluid by deforming the wall of the storage chamber in the thickness direction of the main body. Drive means for conducting or opening through the injection groove portion, and the injection groove portion protrudes inward from the inner wall and has a protruding wall portion having a substantially parallel protruding surface facing the injection port in the thickness direction of the main body portion. A contact opening / closing device provided at a predetermined interval from   2. The contact switching device according to claim 1, wherein the projecting wall portion is formed of a rough surface having fine irregularities on the projecting surface facing the injection port.   2. The contact switching apparatus according to claim 1, wherein the protruding wall portion is formed with a water-repellent water-repellent material coating on the protruding surface facing the injection port.

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