Switch for high frequency

Information

  • Patent Grant
  • 6424242
  • Patent Number
    6,424,242
  • Date Filed
    Wednesday, February 3, 1999
    25 years ago
  • Date Issued
    Tuesday, July 23, 2002
    21 years ago
Abstract
Insulating walls 14 and 15 are arranged between fixed contacts 21a and 23a that face a movable contactor 51b while being able to come in and out of contact with it and a shield plate 24 positioned on the back surface side of the fixed contacts 21a and 23a. With this arrangement, a compact high-frequency use switch having the desired high-frequency characteristic can be obtained with high productivity.
Description




TECHNICAL FIELD




The present invention relates to high-frequency use switches, and in particular, to a high-frequency use switch intended principally for switching a high-frequency current circuit.




BACKGROUND ART




Conventionally, there has been a high-frequency use switch as disclosed, for example, in Japanese Utility Model Publication No. HEI 6-38354, for the purpose of improving the high-frequency characteristic of the high-frequency use switch.




This is a high-frequency use switch such that a box-shaped shield casing is mounted on a substrate that is insert-molded in line with a fixed contact member and a movable contact member is brought in and out of contact with an upper end portion of the fixed contact member that is projecting from a bottom surface of this shield casing, thereby opening and closing the high-frequency current circuit.




However, the aforementioned high-frequency use switch is hard to obtain the desired high-frequency characteristic and also necessitates the box-shaped shield casing having a complicated shape. These factors lead to the problems of low productivity and difficulties in dimensional reduction.




In view of the aforementioned problems, the present invention has the object of providing a compact high-frequency use switch of a high productivity.




DISCLOSURE OF THE INVENTION




In order to achieve the aforementioned object, a first inventive feature of the present application is a high-frequency use switch, wherein a dielectric is arranged between a fixed contact that faces a movable contact while being able to come in and out of contact with it and a shield member located in the vicinity of the fixed contact.




A second inventive feature of the present application is a high-frequency use switch, wherein a plurality of movable contactors that reciprocate in the direction of thickness thereof on the basis of excitation and nonexcitation of an electromagnet block are brought in and out of contact alternately with a common fixed contact and a normally-open fixed contact and with the common fixed contact and a normally-closed fixed contact so as to open and close a high-frequency current circuit, and wherein a dielectric is arranged between the fixed contact and a shield member positioned in the vicinity of the fixed contact.




According to the first or second inventive feature of the present application, the desired frequency characteristic can be secured without using a box-shaped shield casing having a complicated shape as in the prior art. For this reason, a compact high-frequency use switch can be obtained with high productivity.




A third inventive feature is a high-frequency use switch characterized in that the dielectric is an insulating wall integrally formed with a base.




According to the third feature, the dielectric is the insulating wall integrated with the base, and there is a reduction in the number of components and assembling processes. For this reason, a compact high-frequency use switch can be obtained with higher productivity.




A fourth feature is that the dielectric is constructed of a plurality of insulating walls arranged parallel to each other with a distance between opposite faces equal to the thickness of the shield member.




According to the fourth feature, the dielectric serves as a member for positioning the shield member, and therefore, the assembling performance is improved.




A fifth feature is that a lower end portion of a fixed contact terminal provided with the fixed contact and a lower end portion of a ground terminal extended from the shield member are arranged in line with each other.




According to the fifth feature, the terminal portion of the fixed contact terminal and the ground terminal of the shield member are arranged in line with each other. For this reason, the mounting work on a printed board or the like is facilitated to a convenience.




A sixth feature is that a ground tongue with which the movable contactor comes in contact when separated from the fixed contact extends on the shield member.




According to the sixth feature, the movable contactor comes into contact with the ground tongue of the shield member when separated from the fixed contact, and therefore, the high-frequency characteristic when the contact is opened is further improved.




A seventh feature is that an engagement pawl with which a restoration spring for urging the movable contactor is engaged extends on the shield member.




According to the seventh feature, the restoration spring for urging the movable contactor is engaged with the engagement pawl of the shield member, and therefore, the assembly of the switch is facilitated.




An eighth feature is that a pair of common fixed contacts whose contact surfaces to be brought in contact with the movable contactor are directed in opposite directions are provided in upper portions of the common fixed contact terminal.




According to the eighth feature, the different movable contactors alternately come into contact with the pair of fixed contacts provided at the upper portions of the common fixed contact terminal. This arrangement allows the obtainment of a high-frequency use switch capable of opening and closing different high-frequency current circuits with interposition of the dielectric.




A ninth feature is that a pair of movable contactors that are arranged in parallel so as not to face each other are made to simultaneously reciprocate in the direction of plate thickness so as to come in contact alternately with the fixed contact, thereby opening and closing different high-frequency current circuits.




According to the ninth feature, the pair of movable contactors that are arranged in parallel so as not to face each other come in and out of contact alternately with the different fixed contacts. This arrangement allows the obtainment of a high-frequency use switch of which the adjacent movable contactors are magnetically influenced less, assuring a superior high-frequency characteristic.




A tenth feature is that a pair of movable contactors that are arranged in line with one another in an insulated state are made to simultaneously reciprocate in the direction of plate thickness so as to come in contact alternately with the fixed contact, thereby opening and closing different high-frequency current circuits.




According to the tenth feature, the pair of movable contactors arranged in line with each other in the insulated state alternately come in and out of contact with the fixed contact, thereby opening and closing the different high-frequency current circuits. This arrangement allows the obtainment of a high-frequency use switch that facilitates the manufacturing of a movable block having the movable contactor, assuring higher productivity.




An eleventh feature is a high-frequency use switch, wherein a dielectric is arranged between a fixed contact that faces a movable contact while being able to come in and out of contact with it and a shield member positioned roughly in a plane identical to that of the fixed contact.




A twelfth feature is a plurality of movable contactors that reciprocate in the direction of thickness thereof on the basis of excitation and nonexcitation of an electromagnet block are brought in and out of contact alternately with a common fixed contact and a normally-open fixed contact and with the common fixed contact and a normally-closed fixed contact so as to open and close a high-frequency current circuit, and wherein a dielectric is arranged between the fixed contact and the shield member positioned in a plane roughly identical to that of the fixed contact.




According to the eleventh and twelfth features, the desired frequency characteristic can be secured without using a box-shaped shield casing having the complicated shape as in the prior art. For this reason, a compact high-frequency use switch can be obtained with high productivity.




Particularly by arranging the shield member and the fixed contact in the roughly identical planar form, the so-called coplanar guide structure can be constructed. For this reason, a high-frequency use switch having the desired frequency characteristic can be obtained.




Furthermore, the ground terminal of the shield member and the fixed contact are arranged in line with each other, so that the mounting work on the printed board or the like is facilitated.




A thirteenth feature is that the shield member and the fixed contact are integrated with each other by a dielectric.




According to the thirteenth feature, the shield member and the fixed contact are integrated with each other by the dielectric, and therefore, the number of components and the number of assembling processes in the assembling line are reduced to allow the productivity to be improved.




A fourteenth feature is that a ground tongue with which the movable contactor that is separated from the fixed contact comes in contact extends at least in one end portion of the shield member.




According to the fourteenth feature, the movable contactor comes into contact with the ground tongue of the shield member when separated from the fixed contact, and therefore, the high-frequency characteristic when the contact is opened is further improved.




A fifteenth feature is that a bending use shoulder portion is integrally formed with a base portion of the ground tongue.




According to the fifteenth feature, the bending use shoulder portion integrally formed with the base portion of the ground tongue can be used as a reference plane. For this reason, the ground tongue bending work becomes accurate, thereby allowing the assembling accuracy to be improved. Furthermore, the bending work can be performed rapidly, producing the effect of further improving the productivity.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is an exploded perspective view showing a first embodiment of the high-frequency use switch of the present invention;





FIG. 2

is a cross sectional view of the high-frequency use switch shown in

FIG. 1

;





FIG. 3

is a perspective view of the high-frequency use switch shown in

FIG. 1

;





FIG. 4

is a perspective view showing a state in which the electromagnet block is dismounted from the high-frequency use switch of

FIG. 3

;





FIG. 5

is a plan view of

FIG. 4

;





FIG. 6

is a perspective view of the fixed contact mechanism shown in

FIG. 1

;





FIG. 7

is a front view of

FIG. 6

;





FIG. 8

is an exploded perspective view of the movable block shown in

FIG. 1

;





FIG. 9A

is a perspective view of a movable block according to another embodiment;





FIG. 9B

is a side view thereof;





FIG. 10

is a perspective view showing a second embodiment;





FIG. 11

is a plan view of

FIG. 10

;





FIG. 12

is a perspective view of the fixed contact mechanism shown in

FIG. 10

;





FIG. 13

is a front view of

FIG. 12

;





FIG. 14

is a perspective view of a third embodiment;





FIG. 15

is a sectional plan view of

FIG. 14

;





FIG. 16

is a perspective view of a fourth embodiment;





FIG. 17

is a plan view of

FIG. 16

;





FIG. 18

is a perspective view of the fixed contact mechanism shown in

FIG. 16

;





FIG. 19

is a graph showing measurement results of high-frequency characteristic in the case where the contact is opened;





FIG. 20

is a graph showing measurement results of high-frequency characteristic in the case where the contact is closed;





FIG. 21

is an exploded perspective view showing a fifth embodiment of the high-frequency use switch of the present invention;





FIG. 22

is a longitudinal sectional view of the high-frequency use switch shown in

FIG. 21

;





FIG. 23

is a perspective view of the high-frequency use switch shown in

FIG. 21

;





FIG. 24

is a cross sectional view of the fixed contact block shown in

FIG. 21

;





FIG. 25

is a perspective view showing a method for manufacturing a fixed contact block according to a sixth embodiment;





FIG. 26

is a perspective view showing a method for manufacturing a fixed contact block according to the sixth embodiment;





FIG. 27

is a perspective view of the fixed contact block of the sixth embodiment;





FIG. 28A

is a plan view of the fixed contact block shown in

FIG. 27

;





FIG. 28B

is an enlarged view of part thereof;





FIG. 29

is a perspective view of a high-frequency use switch according to a seventh embodiment;





FIG. 30

is a perspective view of the fixed contact block shown in

FIG. 29

;





FIG. 31

is a front view of

FIG. 30

;





FIG. 32

is a perspective view of the base assembled with the fixed contact block shown in

FIG. 30

;





FIG. 33

is a plan view of

FIG. 32

;





FIG. 34

is a graph showing measurement results of high-frequency characteristic in the case where the contact is opened; and





FIG. 35

is a graph showing measurement results of high-frequency characteristic in the case where the contact is closed.











BEST MODE FOR CARRYING OUT THE INVENTION




Embodiments of the present invention will be described next with reference to the accompanying drawings of FIG.


1


through FIG.


35


.




As shown in FIG.


1


through

FIG. 9

, a first embodiment is constructed roughly of a base


10


, a fixed contact mechanism


20


, an electromagnet block


30


, an armature


40


, a movable block


50


and a casing


60


.




The base


10


is provided with support walls


12


and


13


that project at the corner portions on the opposite sides of a flat base body


11


made of a dielectric (synthetic resin) and with discontinuous insulating walls


14


,


15


,


16


and


17


arranged between them. Upper end portions of the support walls


12


and


13


are formed with bearing grooves


12




a


and


13




a,


respectively, for pivotally supporting the movable block


50


described later. A base portion of the support wall


13


is formed with a positioning use projecting portion


18


provided with an arc surface that serves as a pivot support of the armature


40


described later.




The fixed contact mechanism


20


is constructed of identically-shaped fixed contact terminals


21


and


22


having fixed contacts


21




a


and


22




a,


respectively, a common fixed contact terminal


23


having common fixed contacts


23




a


and


23




b


and a shield plate


24


.




In particular, the fixed contact


21




a


and the common fixed contact


23




a


constitute a normally-open fixed contact mechanism, while the fixed contact


22




a


and the common fixed contact


23




b


constitute a normally-closed fixed contact mechanism.




As shown in FIG.


6


and

FIG. 7

, the shield plate


24


is formed by punching a plate-shaped conductive material into a specified shape and press-processing the same. Then, the shield plate


24


has a plurality of ground terminals


25


projecting in line with one another on the lower side and ground tongues


26




a


and


26




b


formed by inwardly bending extended both end portions. Further, an engagement pawl


27


to be engaged with a restoration spring


56


for the movable block


50


, described later, is projecting from an upper edge portion of the shield plate


24


.




By press-fitting the lower end portions of the fixed contact terminals


21


and


22


and the common fixed contact terminal


23


as well as the ground terminals


25


of the shield plate


24


into terminal holes of the base


10


, then, as shown in

FIG. 5

, the lower end portions of the fixed contact terminals


21


and


22


, the common fixed contact terminal


23


and the ground terminals


25


are arranged in line with one another. Further, the fixed contacts


21




a


and


22




a


and the common fixed contacts


23




a


and


23




b


abut against the side surfaces of the insulating walls


14


and


17


and the insulating walls


15


and


16


, respectively, thereby shielding one side of the fixed contacts


21




a


and


22




a


and the common fixed contacts


23




a


and


23




b


. With this arrangement, a shield structure utilizing the principle of the so-called strip line is obtained.




The electromagnet block


30


is formed by inserting an iron core


33


having a roughly. T-figured section shape into a center hole


32




a


of a spool


32


around which a coil


31


is wound. The one end portion projecting from the center hole


32




a


is made to serve as a magnetic pole piece


33




a,


while the projecting other end portion


33




b


is fixed in a caulking manner to one end portion of a yoke


34


bent roughly in an L-figured shape. Coil terminals


35


are press-fit into flange portions


32




b


of the spool


32


, and a lead wire of the coil


31


is wound around and soldered to this.




Then, by press-fitting the coil terminals


35


into terminal holes


11




a


of the base


10


, the electromagnet block


30


is positioned in the specified position.




The armature


40


is made of magnetic material and bent roughly in an L-figured shape, and its one end portion is formed into a narrowed portion


41


.




The armature


40


is assembled from above along the positioning use projecting portion


18


that is projecting from the upper surface of the base. Therefore, the armature


40


is pivotally supported on the inner surface of the positioning use projecting portion


18


used as a support, and its one end portion


42


can abut against the magnetic pole piece


33




a


of the iron core


33


.




As shown in

FIG. 8

, the movable block


50


is made of a pair of movable bases


51


and


52


having an identical shape and a restoration spring


56


.




The movable bases


51


and


52


are constructed so that movable contactors


51




b


and


52




b


are insert-molded into the lower end portions of projecting bars


51




a


and


52




a


extended downward from the side surfaces. The movable bases


51


and


52


have shaft portions


53


that project laterally from their one side end portions as well as engagement use projecting portions


54


and


54


that project laterally from their other side end portions.




The shaft portions


53


have an escape formed with flat surfaces


53




a


and


53




b


that are vertically parallel to each other. Further, a burr that cannot be avoided in the resin forming process is generated on the flat surfaces


53




a


and


53




b,


thereby allowing a smooth pivoting operation to be obtained.




The base portion of the engagement use projecting portion


54


is formed with a recess portion


55


to be engaged therewith. Further, the projecting portion


54


is formed with a projection


54




a


to be press-fit into the through hole


55




a


formed in a recess portion


55


for the engagement.




Then, the projecting portion


54


of the movable base


51


is positioned while being fit in the recess portion


55


of the movable base


52


. Then, the projection


54




a


and the through hole


55




a


of the movable base


51


are press-fit on the through hole


55




a


and the projection


54




a


of the movable base


52


, temporarily fixed and thereafter connected and integrated with each other by adhesive, high-frequency welding or other means.




Further, by mounting a gripping portion


57


of the restoration spring


56


on the upper edge portions of the movable bases


51


and


52


that have been connected and integrated with each other, the movable block


50


is completed.




According to the present embodiment, the movable bases


51


and


52


having the identical shape are used, and accordingly, there is the advantage that the resin molding is simplified and the manufacturing of the metal mold can be facilitated.




Then, the shaft portions


53


and


53


of the movable block


50


are fit into the bearing grooves


12




a


and


13




a


of the base


10


, thereby pivotally supporting the movable block


50


in the direction of its thickness. With this arrangement, the movable contactor


51




b


faces the fixed contacts


21




a


and


23




a


or the ground tongue


26




a


while being able to come into and out of contact alternately with them. On the other hand, the movable contactor


52




b


faces the fixed contacts


22




a


and


23




b


or the ground tongue


26




b


while being able to come into and out of contact alternately with them. Then, the tip portion of the restoration spring


56


is engaged with the engagement pawl


27


of the shield plate


24


, thereby urging the movable block


50


toward the electromagnet block


30


side.




Although: the aforementioned embodiment has been described on the basis of the case where the movable block


50


is formed by combining the two movable bases


51


and


52


with each other, the present invention is not always limited to this. As shown in

FIGS. 9A and 9B

, the movable block


50


may be integrally formed originally. According to this embodiment, the movable block


50


having a high dimensional accuracy free of any assembling error as observed in the aforementioned embodiment can be obtained. This arrangement has the advantage that a high-frequency use switch of uniform operation characteristics can be obtained.




The casing


60


has a box-like shape that can fit on the base


10


, and portions that belong to its ceiling surface and are located just above the shaft portions


53


of the movable block


50


are provided with a positioning use projecting portion


61


for preventing a lift (see FIG.


2


).




When the casing


60


is fit on the base


10


integrated with the internal components, the positioning use projecting portion


61


faces the flat surface


53




a


of the shaft portion


53


with a minute gap retained between them. Then, by sealing the contact surface of the base


10


and the casing


60


with a sealant, the assembling work is completed.




The operation of the high-frequency use switch having the aforementioned construction will be described next.




When no voltage is applied to the coil


31


of the electromagnet block


30


, the movable block


50


is urged toward the electromagnet block


30


side by a spring force of the restoration spring


56


. Then, the movable contactor


51




b


is put in contact with the ground tongue


26




a,


while the movable contactor


52




b


is put in contact with the fixed contacts


23




b


and


22




a.






When a voltage is applied to the coil


31


for the excitation, the one end portion


42


of the armature


40


is attracted to the magnetic pole piece


33




a


of the iron core


33


. By this operation, the armature


40


pivots to make its narrowed portion


41


press the movable block


50


outward against the spring force of the restoration spring


56


. Consequently, the movable block


50


pivots around the shaft portions


53


, and the movable contactor


51




b


separates from the ground tongue


26




a


and comes into contact with the fixed contacts


21




a


and


23




a


. On the other hand, the movable contactor


52




b


separates from the fixed contacts


23




b


and


22




a


and comes into contact with the ground tongue


26




b.


Thereafter, the one end portion


42


of the armature


40


is attracted to the magnetic pole piece


33




a


of the iron core


33


.




Subsequently, if the application of the voltage to the coil


31


is stopped, then the movable block


50


pivots in the direction opposite to the pivotal direction by the spring force of the restoration spring


56


. By this operation, the movable contactor


51




b


comes into contact with the ground tongue


26




a


, and the movable contactor


52




b


comes into contact with the fixed contacts


23




b


and


22




a,


achieving restoration into the original state.




In contrast to the aforementioned first embodiment in which the movable block


50


is pivotally supported by the support walls


12


and


13


that are integrally formed with the base


10


, a second embodiment is as shown in FIG.


10


through

FIG. 13

, in which support flaps


28


and


29


extend from both end portions of a shield plate


24


that is arranged upright while being press-fit into the base


10


and the shaft portions


53


and


53


of the aforementioned movable block


50


are pivotally supported while being inserted in bearing holes


28




a


and


29




a


provided for the support flaps


28


and


29


.




As shown in

FIG. 11

, similar to the aforementioned first embodiment, the back surfaces of the fixed contacts


21




a


and


22




a


and the common fixed contacts


23




a


and


23




b


abut against the insulating walls


14


and


17


and


15


and


16


projecting from the base


10


, constituting a strip line in the present embodiment.




It is to be noted that the shield plate


24


has an engagement pawl


27


which is laterally extended from its support flap


28


and with which the free end portion of the restoration spring


56


is engaged. Further, the shield plate


24


has positioning tongues


29




b


which are laterally extended from the other support flap


29


and are brought in pressure contact with the bent corner portion of the armature


40


so as to pivotally support the armature.




According to the present embodiment, the fixed contact terminals


21


and


22


and the common fixed contact terminal


23


can be press-fit from below the base


10


, while the shield plate


24


can be press-fit from above. This arrangement has the advantage that the degree of freedom in assembling expands. The other part is similar to that of the aforementioned first embodiment, and therefore, no description is provided therefor.




A third embodiment is as shown in FIG.


14


and

FIG. 15

, in which a strip line is constituted via an insulating wall


18


separated from the base


10


.




That is, the fixed contact terminals


21


and


22


and the common fixed contact terminal


23


are press-fit between three pairs of press-fitting use projecting portions


18




a


and


18




b


projecting from lower edge portions of the surface of the insulating wall


18


of a synthetic resin mold, while a shield plate


24


is assembled with the back surface of the insulating wall


18


.




Then, a movable contactor


51




b


or


52




b


that reciprocates in the direction of plate thickness on the basis of excitation and nonexcitation of the electromagnet block (not shown) is brought in and out of contact alternately with the fixed contacts


21




a


and


23




a


or the fixed contacts


23




b


and


22




a,


thereby opening and closing the contact.




Although the present embodiment has been described on the basis of the case where the insulating wall


18


is formed separately from the base


10


. However, the present invention is not always limited to this, and the insulating wall may be integrally formed with the base


10


.




A fourth embodiment is as shown in FIG.


16


through

FIG. 18

, in which movable contactors


51




b


and


52




b


are arranged in line with each other. Due to this arrangement, the insulating walls


14


,


15


,


16


and


17


of the base


10


are projecting in correspondence with a shield plate


24


bent roughly in the middle portion thereof.




According to the present embodiment, the two movable contactors


51




b


and


52




b


are arranged in line with each other. This arrangement has the advantage that the manufacturing can be facilitated to allow a movable block having a high dimensional accuracy to be manufactured and allow the prevention of the occurrence of a variation in operation characteristics. The other part is similar to that of the aforementioned embodiment, and therefore, no description is provided therefor.




FIRST EXPERIMENTAL EXAMPLE




The high-frequency use switch having the shield structure described in connection with the first embodiment was measured with regard to its high-frequency characteristic in the case where the contact circuit corresponding to the movable contactor


51




b


was opened and in the case where the contact circuit was closed. The measurement results are shown in FIG.


19


and FIG.


20


.




PRIOR ART EXAMPLE




The high-frequency use switch described in connection with the prior art was measured similar to the first experimental example with regard to its high-frequency characteristic in the case where the contact circuit corresponding to the movable contactor was opened and in the case where the contact circuit was closed. The measurement results are shown in FIG.


19


and FIG.


20


.




As is apparent from

FIG. 19

, it can be found that the present first experimental example is always superior with regard to the high-frequency characteristic in the case where the contact is opened. The difference is remarkable particularly above 2000 MHz.




As is also apparent from

FIG. 20

, it can be found that the present first experimental example is always superior with regard to the high-frequency characteristic in the case where the contact is closed. The difference is remarkable particularly above 2000 MHz.




This can be considered to be ascribed to the fact that impedance matching can be attained almost throughout the entire range in the first experimental example as compared with the fact that impedance matching can be attained only partially in the prior art.




The dielectric positioned on the back surface of the fixed contact is not always required to be an insulating wall projecting from the base and is allowed to be a coating film or a sheet, which is made of a dielectric material and is laminated on the side surface of the shield plate.




As shown in FIG.


21


through

FIG. 24

, a high-frequency use switch according to a fifth embodiment is constructed roughly of a base


110


, a fixed contact mechanism


120


, an electromagnet block


130


, an armature


140


, a movable block


150


and a casing


160


.




The base


110


is provided with support walls


112


and


113


that project at the corner portions on the opposite sides of a flat base body


111


made of a dielectric (synthetic resin) and terminal holes for arranging a fixed contact block


120


described later between them. Upper end portions of the support walls


112


and


113


are formed with bearing grooves


112




a


and


113




a,


respectively, for pivotally supporting the movable block


150


described later. A base portion of the support wall


113


is formed with a positioning use projecting portion


114


provided with an arc surface that serves as a pivot support of the armature


140


described later.




The fixed contact block


120


is constructed of identically-shaped fixed contact terminals


121


and


122


having fixed contacts


121




a


and


122




a,


respectively, a common fixed contact terminal


123


having fixed contacts


123




a


and


123




b


and a shield plate


24


, which are integrally formed with a retainer


120




a


made of a synthetic resin, or a dielectric.




In particular, the fixed contact


121




a


and the common fixed contact


123




a


constitute a normally-open fixed contact mechanism, while the fixed contact


122




a


and the common fixed contact


123




b


constitute a normally-closed fixed contact mechanism.




The shield plate


124


is formed by punching a plate-shaped conductive material into a specified shape and press-processing the same. Then, the shield plate


124


has a plurality of ground terminals


125


projecting in line with one another on the lower side and ground tongues


126




a


and


126




b


formed by inwardly bending extended both end portions. Further, an engagement pawl


127


to be engaged with a restoration spring


156


for the movable block


150


, described later, is projecting from an upper edge portion of the shield plate


124


.




Therefore, by positioning the upper end portions of the fixed contact terminals


121


and


122


and the common fixed contact terminal


123


in cut portions provided on the lower side of the shield plate


124


and thereafter integrally forming these members with the retainer


120




a,


the fixed contacts


121




a


and


122




a


and the common fixed contacts


123




a


and


123




b


are exposed sideward. Further, as shown in

FIG. 24

, the fixed contacts


121




a


and


122




a


of the fixed contact terminals


121


and


122


, the fixed contacts


123




a


and


123




b


of the common fixed contact terminal


123


and the shield plate


124


are arranged roughly in line with one another via the retainer


120




a.


With this arrangement, the so-called coplanar guide structure is obtained.




Then, the fixed contact block


120


is assembled by press-fitting its fixed contact terminals


121


and


122


, the lower end portion of the common fixed contact terminal


123


and the ground terminal


125


of the shield plate


124


into the terminal holes of the base


110


.




The electromagnet block


130


is formed by inserting an iron core


133


having a roughly T-figured section shape into a center hole


132




a


of a spool


132


around which a coil


131


is wound. The one end portion projecting from the center hole


132




a


is made to serve as a magnetic pole piece


133




a,


while the projecting other end portion


133




b


is fixed in a caulking manner to one end portion of a yoke


134


bent roughly in an L-figured shape. Coil terminals


135


are press-fit into flange portions


132




b


of the spool


132


, and a lead wire of the coil


131


is wound around and soldered- to this.




Then, by press-fitting the coil terminals


135


into terminal holes


111




a


of the base


110


, the electromagnet block


130


is positioned in the specified position.




The armature


140


is made of magnetic material and bent roughly in an L-figured shape, and its one end portion is formed into a narrowed portion


141


.




The armature


140


is assembled from above along the positioning use projecting portion


114


that is projecting from the upper surface of the base. Therefore, the armature


140


is pivotally supported on the inner surface of the positioning use projecting portion


114


used as a support, and its one end portion


142


can abut against the magnetic pole piece


133




a


of the iron core


133


.




The movable block


150


is made of a pair of movable bases


151


and


152


having an identical shape and a restoration spring


156


.




The movable bases


151


and


152


are constructed so that movable contactors


151




b


and


152




b


are insert-molded into the lower end portions of projecting bars


151




a


and


152




a


extended downward from the side surfaces. The movable bases


151


and


152


have shaft portions


153


that project laterally from their one side end portions as well as engagement use projecting portions


154


that project laterally from their other side end portions.




The shaft portions


153


have an escape formed with flat surfaces


153




a


and


153




b


that are vertically parallel to each other. Further, a burr that cannot be avoided in the resin forming process is generated on the flat surfaces


153




a


and


153




b,


thereby allowing a smooth pivoting operation to be obtained.




The base portion of the engagement use projecting portion


154


is formed with a recess portion


155


to be engaged therewith. Further, the projecting portion


154


is formed with a projection


154




a


to be press-fit into the through hole


155




a


formed in a recess portion


155


for the engagement.




Then, the projecting portion


154


of the movable base


151


is positioned while being fit in the recess portion


155


of the movable base


152


. Then, the projection


154




a


and the through hole


155




a


of the movable base


151


are press-fit on the through hole


155




a


and the projection


154




a


of the movable base


152


, temporarily fixed and thereafter connected and integrated with each other by adhesive, high-frequency welding or other means.




Further, by mounting a gripping portion


157


of the restoration spring


156


on the upper edge portions of the movable bases


151


and


152


that have been connected and integrated with each other, the movable block


150


is completed.




According to the present embodiment, the movable bases


151


and


152


having the identical shape are used, and accordingly, there is the advantage that the resin molding is simplified and the manufacturing of the metal mold can be facilitated.




Then, the shaft portions


153


and


153


of the movable block


150


are fit into the bearing grooves


112




a


and


113




a


of the base


110


, thereby pivotally supporting the movable block


150


in the direction of thickness. With this arrangement, the movable contactor


151




b


faces the fixed contacts


121




a


and


123




a


or the ground tongue


126




a


while being able to come into and out of contact alternately with them. On the other hand, the movable contactor


152




b


faces the fixed contacts


122




a


and


123




b


or the ground tongue


126


b while being able to come into and out of contact alternately with them. Then, the tip portion of the restoration spring


156


is engaged with the engagement pawl


127


of the shield plate


124


, thereby urging the movable block


150


toward the electromagnet block


130


side.




The casing


160


has a box-like shape that can fit on the base


110


, and portions that belong to its ceiling surface and are located just above the shaft portions


153


of the movable block


150


are provided with a positioning use projecting portion


161


for preventing a lift (see FIG.


22


).




When the casing


160


is fit on the base


110


integrated with the internal components, the positioning use projecting portion


161


faces the flat surface


153




a


of the shaft portion


153


with a minute gap retained between them. Then, by sealing the contact surface of the base


110


and the casing


160


with a sealant, the assembling work is completed.




The operation of the high-frequency use switch having the aforementioned construction will be described next.




When no voltage is applied to the coil


131


of the electromagnet block


130


, the movable block


150


is urged toward the electromagnet block


130


side by a spring force of the restoration spring


156


. Then, the movable contactor


151




b


is put in contact with the ground tongue


126




a


, while the movable contactor


152




b


is put in contact with the fixed contacts


123




b


and


122




a.






When a voltage is applied to the coil


131


for the excitation, the one end portion


142


of the armature


141


is attracted to the magnetic pole piece


133




a


of the iron core


133


. By this operation, the armature


140


pivots to make its narrowed portion


141


press the movable block


150


outward against the spring force of the restoration spring


156


. Consequently, the movable block


150


pivots around the shaft portions


153


, and the movable contactor


151




b


separates from the ground tongue


126




a


and comes into contact with the fixed contacts


121




a


and


123




a


. On the other hand, the movable contactor


152




b


separates from the fixed contacts


123




b


and


122




a


and comes into contact with the ground tongue


126




b.


Thereafter, the one end portion


142


of the armature


140


is attracted to the magnetic pole piece


133




a


of the iron core


133


.




Subsequently, if the application of the voltage to the coil


131


is stopped, then the movable block


150


pivots in the direction opposite to the pivotal direction by the spring force of the restoration spring


156


. By this operation, the movable contactor


151




b


comes into contact with the ground tongue


126




a


, and the movable contactor


152




b


comes into contact with the fixed contacts


123




b


and


122




a,


achieving restoration into the original state.




A sixth embodiment is as shown in FIG.


25


through

FIG. 28B

, in which the retainer


120




a


is integrally formed with the fixed contact terminals


121


and


122


integrally cut out of a lead frame


124




a


, the common fixed contact terminal


123


and the shield plate


124


(see FIG.


26


). A shoulder portion


120




b


that serves as a reference in bending the ground tongues


126




a


and


126




b


extends from one end portion of this retainer


120




a.






According to the present embodiment, the shoulder portion


120




b


serves as a reference in bending the ground tongues


126




a


and


126




b.


This arrangement has the advantage that the bending work of the ground-tongues


126




a


and


126




b


can be performed correctly and speedily.




Therefore, according to the present embodiment, the fixed contact terminals


121


and


122


, the common fixed contact terminal


123


and the shield plate


124


are cut out of the lead frame


124




a


, and thereafter the retainer


120




a


is integrally formed. Then, by separating the fixed contact terminals


121


and


122


and the shield plate


124


from the lead frame


124




a


and thereafter bending the ground tongues


126




a


and


126




b,


the fixed contact block


120


is completed. The other part is similar to that of the aforementioned first embodiment, and therefore, no description is provided therefor.




In contrast to the aforementioned fifth and sixth embodiments in which the movable block


150


is pivotally supported by the support walls


112


and


113


that are integrally formed with the base


110


, a seventh embodiment is as shown in FIG.


29


through

FIG. 33

, in which support flaps


128


and


129


extend from both end portions of the shield plate


124


that is arranged upright while being press-fit into the base


10


and the shaft portions


153


and


153


of the aforementioned movable block


150


are pivotally supported while being inserted in bearing holes


128




a


and


129




a


provided for the support flaps


128


and


129


.




As shown in

FIG. 30

, similar to the aforementioned fifth and sixth embodiments, the fixed contacts


121




a


and


122




a


and the fixed contacts


123




a


and


123




b


are arranged roughly in line with the shield plate


124


, constituting a coplanar guide structure in the present embodiment.




It is to be noted that the shield plate


124


has an engagement pawl


127


which is laterally extended from its support flap


128


and with which the free end portion of the restoration spring


156


is engaged. Further, the shield plate


124


has positioning tongues


129




b


which are laterally extended from the other support flap


29


and are brought in pressure contact with the bent corner portion of the armature


140


so as to pivotally support the armature.




Therefore, similar to the aforementioned sixth embodiment, the retainer


120




a


is integrally formed with the fixed contact terminals


121


and


122


, the common fixed contact terminal


123


and the shield plate


124


cut out of a lead frame (not shown). Subsequently, by separating the fixed contact terminals


121


and


122


and so on from the lead frame, the fixed contact block


120


is obtained. Further, the fixed contact terminals


121


and


122


of this fixed contact block


120


, the lower end portion of the common fixed contact terminal


123


and the ground terminals


125


of the shield plate


124


are press-fit into the base


110


to be assembled therewith. The other part is almost similar to that of the aforementioned first embodiment, and therefore, no description is provided therefor.




SECOND EXPERIMENTAL EXAMPLE




The high-frequency use switch having the shield structure described in connection with the fifth embodiment was measured with regard to its high-frequency characteristic in the case where the contact circuit corresponding to the movable contactor


51




b


was opened and in the case where the contact circuit was closed. The measurement results are shown in FIG.


34


and FIG.


35


.




PRIOR ART EXAMPLE




The high-frequency use switch described in connection with the prior art was measured similar to the second experimental example with regard to its high-frequency characteristic in the case where the contact circuit corresponding to the movable contactor was opened and in the case where the contact circuit was closed. The measurement results are shown in FIG.


34


and FIG.


35


.




As is apparent from

FIG. 34

, it can be found that the present second experimental example is always superior with regard to the high-frequency characteristic in the case where the contact is opened. The difference is remarkable particularly above 2000 MHz.




As is also apparent from

FIG. 35

, it can be found that the present second experimental example is always superior with regard to the high-frequency characteristic in the case where the contact is closed. The difference is remarkable particularly above 2000 MHz.




This can be considered to be ascribed to the fact that impedance matching can be attained almost throughout the entire range in the second experimental example as compared with the fact that impedance matching can be attained only partially in the prior art.




The retainer


120




a


of the fixed contact block


120


is not always required-to be separated from the base


110


and is, of course, allowed to be integrally formed with the base


110


.




INDUSTRIAL APPLICABILITY




The present invention can be applied not only to the high-frequency use switches of the aforementioned embodiments but also to the high-frequency use switches of other high-frequency use switches.



Claims
  • 1. A high-frequency switch, wherein a pair of movable contacts that reciprocate in a direction of thickness thereof on a basis of excitation and nonexcitation of an electromagnetic block have end portions, both of the end portions of each movable contact are brought in and out of contact alternately with a normally-open common fixed contact and a normally-open fixed contact and with a normally-closed common fixed contact and a normally-closed fixed contact to open and close different high-frequency current circuits; andwherein the pair of movable contacts are arranged in parallel so as not to face each other, the normally-open common fixed contact and the normally-closed common fixed contact extend in opposite directions, and dielectrics, made of insulating walls molded integral with a base, are respectively arranged between the normally-open common fixed contact and the normally-open fixed contact, and a normally-open shield member, and between the normally-closed common fixed contact and the normally-closed fixed contact, and a normally-closed shield member.
  • 2. A high frequency switch, wherein a pair of movable contacts that reciprocate in a direction of thickness thereof on a basis of excitation and nonexcitation of an electromagnet block have end portions, both of the end portions of each movable contact are brought in and out of contact alternately with a normally-open common fixed contact and a normally-open fixed contact and with a normally-closed common fixed contact and a normally-closed fixed contact to open and close different high-frequency current circuits; andwherein the pair of movable contacts are arranged in parallel so as not to face each other, the normally-open common fixed contact and the normally-closed common fixed contact extend in a same direction so as to be integral with each other, and a dielectric made of a molded insulating material is arranged between the normally-open common fixed contact, the normally-closed common fixed contact, the normally open fixed contact and the normally closed fixed contact, and a shield member.
  • 3. A high-frequency switch, wherein a pair of movable contacts that reciprocate in a direction of thickness thereof on a basis of excitation and nonexcitation of an electromagnet block have end portions, both of the end portions of each movable contact are brought in and out of contact alternately with a normally-open common fixed contact and a normally-open fixed contact and with a normally-closed common fixed contact and a normally-closed fixed contact to open and close different high-frequency current circuits; andwherein the pair of movable contacts are arranged in line with one another in an insulated state, the normally-open common fixed contact and the normally-closed common fixed contact extend in opposite directions, and dielectrics made of a insulating walls, which are molded integral with a base, are respectively arranged between the normally-open common fixed contact and the normally-open fixed contact, and a normally-open shield member, and between the normally-closed common fixed contact and the normally-closed fixed contact, and a normally-closed shield member.
  • 4. A high-frequency switch as claimed in claim 2, whereinthe dielectric is constructed of at least a pair of insulating walls arranged parallel to each other with a distance between each pair adjacent insulating walls equal to a thickness of the shield member.
  • 5. A high-frequency switch as claimed in claim 1, whereina lower end portion of a fixed contact terminal provided with the fixed contact and a lower end portion of a ground terminal extended from the shield member are arranged in line with each other.
  • 6. A high-frequency switch as claimed in claim 2, whereina ground tongue extending on the shield member and with which the movable contact comes in contact when separated from the fixed contacts.
  • 7. A high-frequency switch as claimed in claim 1, further comprisingan engagement pawl engaging a restoration spring and extending on the shield member, the restoration spring biasing the movable contact.
  • 8. A high-frequency switch, wherein a pair of movable contacts that reciprocate in a direction of thickness thereof on a basis of excitation and nonexcitation of an electromagnet block have end portions, both of the end portions of each movable contact are brought in and out of contact alternately with a normally-open common fixed contact and a normally-open fixed contact and with a normally-closed common fixed contact and a normally-closed fixed contact to open and close different high-frequency current circuits; andwherein the pair of movable contacts are arranged in parallel so as not to face each other, the normally-open common fixed contact and the normally-closed common fixed contact extend in opposite directions; a normally-open shield member is arranged between the normally-open common fixed contact and the normally-open fixed contact, a normally-closed shield member is arranged between the normally-closed common fixed contact and the normally-closed fixed contact, and dielectrics made of insulating walls, which are molded integral with a base or the shield member, are respectively arranged between the fixed contacts and the shield member.
  • 9. A high-frequency switch, wherein a pair of movable contacts that reciprocate in a direction of thickness thereof on a basis of excitation and nonexcitation of an electromagnet block have end portions, both of the end portions of each movable contact are brought in and out of contact alternately with a normally-open common fixed contact and a normally-open fixed contact and with a normally-closed common fixed contact and a normally-closed fixed contact to open and close different high-frequency current circuits; andwherein the pair of movable contacts are arranged in parallel so as not to face each other, the normally-open common fixed contact and the normally-closed common fixed contact extend in opposite directions, a normally-open shield member is arranged between the normally-open common fixed contact and the normally-open fixed contact, a normally-closed shield member is arranged between the normally-closed common fixed contact and the normally-closed fixed contact, and dielectrics made of a insulating walls, which are molded integral with a base or the shield member, are respectively arranged on a side surface of the normally-open common fixed contact, the normally-closed common fixed contact, and the normally-open shield member, and on a side surface of the normally-closed common fixed contact, the normally-closed fixed contact and the normally-closed shield member.
  • 10. A high-frequency switch as claimed in claim 8, whereina ground tongue extending from at least one end portion of a shield member and with which the movable contact that is separated from the fixed contacts comes in contact.
  • 11. A high-frequency switch as claimed in claim 9, whereina bending shoulder portion is integrally formed with a base portion of a ground tongue.
Priority Claims (2)
Number Date Country Kind
8-210924 Aug 1996 JP
8-222186 Aug 1996 JP
PCT Information
Filing Document Filing Date Country Kind
PCT/JP97/02747 WO 00
Publishing Document Publishing Date Country Kind
WO98/07169 2/19/1998 WO A
US Referenced Citations (4)
Number Name Date Kind
4740771 Motoyama et al. Apr 1988 A
5025237 Yamazki et al. Jun 1991 A
5025238 Matuo et al. Jun 1991 A
5644115 Knauer Jul 1997 A
Foreign Referenced Citations (9)
Number Date Country
0 249 758 Dec 1987 EP
0 334 393 Sep 1989 EP
0 336 445 Oct 1989 EP
0 361 442 Apr 1990 EP
3-167725 Jul 1991 JP
5-205597 Aug 1993 JP
6-38354 Oct 1994 JP
6-333481 Dec 1994 JP
7-65684 Mar 1995 JP
Non-Patent Literature Citations (1)
Entry
European Search Report for EP Application No. 97934718.4-2302-JP9702747