JPH113637A - High frequency switch - Google Patents

Abstract

(57) [Problem] To provide a small high-frequency changeover switch that can withstand a large number of inspections. SOLUTION: An elastic member is arranged below a switching spring to apply or strengthen an upward bias to the switching spring, and also to enhance a restoring force, so that a contact plate arranged above the switching spring is provided. To maintain the contact state. Furthermore, by making the shape of the elastic member, for example, an abacus, the switching spring and the contact plate can be reliably separated at the time of inspection.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-frequency changeover switch, and more particularly to a small high-frequency coaxial changeover switch used for inspecting a high-frequency circuit.

[0002]

2. Description of the Related Art High-frequency devices such as cellular phones, BS televisions, and wireless devices often require performance tests of high-frequency circuits provided in these devices. For this purpose, these devices usually incorporate a small high-frequency changeover switch. As a conventional example of such a switch, for example, Japanese Unexamined Patent Publication No.
No. 6 discloses this. The switch disclosed here is a type of switch called a so-called coaxial switch. This type of switch is provided with a pair of conductive plates including a conductive plate having a spring property and a conductive plate fixedly provided. These conductive plates are usually in a contact state, and the contact is interrupted only when a high-frequency circuit is inspected. The disconnection is performed by inserting an inspection needle or the like into the switch from the outside.
The inserted inspection needle divides the connection between the conductive plates by displacing the conductive plate having the spring property, and extracts electricity to the outside through electrical contact with the conductive plate having the spring property. The extracted electrical signal can be used for inspection or the like.

However, in this configuration, the number of inspections,
Therefore, as the number of times of displacement of the conductive plate having the spring property increases, the spring property of the conductive plate decreases, and as a result, the conductive plate displaced after the inspection cannot be completely restored to the original position, and the distance between the conductive plates cannot be reduced. May not be able to maintain the contact state. Because the spring property of the conductive plate relies only on the conductive plate itself that can be generated by applying a spring stress to the conductive plate, it is difficult to maintain the spring stress by a large number of displacements. It is. In order to solve this problem, a conventional method has been to strengthen a fixing portion of the conductive plate to be displaced so that it can withstand a large number of displacement operations.

[0004]

However, if the fixed portion of the conductive plate is strengthened so that it can withstand a large number of displacement operations, there is a disadvantage that the switch becomes large. This solution is not preferred in this type of switch where miniaturization is desired. In addition to this problem, in the conventional apparatus, dust easily accumulates between the conductive plates, and there is a risk that the dust may cause a contact failure. The present invention has been made to solve such a conventional problem, and provides a small-sized switch that can withstand a large number of inspections by reinforcing the spring property of a conductive plate in a smaller space. The purpose is to do. Furthermore, by placing the elastic member below the conductive plate to reinforce the spring property of the conductive plate, a small switch that can reliably maintain the contact state between the conductive plates even when displaced many times. To provide. Further, the present invention provides a switch for effectively preventing a possibility that a contact failure occurs due to dust generated between conductive plates.

[0005]

In order to achieve the above object, the present invention relates to a high-frequency change-over switch which is inserted and connected by dividing a high-frequency circuit of a high-frequency device, wherein one of the divided high-frequency circuits is provided. A switching spring portion having one end connected to the side,
A connection plate portion having one end connected to the other side of the high-frequency circuit to be divided, and the other end of the switching spring portion is always in contact with the other end of the connection plate portion to close the high-frequency circuit. But
An elastic member for reinforcing the resilience of the switching spring is provided in a high-frequency switching switch that separates the high-frequency circuit away from the other end of the connection plate by pressing and displacing the switching spring during signal extraction. It is characterized by. In the present invention, the elastic member is preferably made of a molded rubber material disposed below the switching spring portion with respect to a predetermined position in the insulating housing of the high frequency changeover switch.

In the present invention, it is preferable that the molded rubber material has a shape which can be elastically displaced without any trouble in the insulating housing when the switching spring is pressed and displaced. In the present invention, the elastic member preferably has a symmetric shape. In the present invention, the elastic member preferably has an abacus bead shape. In the present invention, the elastic member is preferably formed by bending a metal piece. In the present invention, the elastic member is preferably formed integrally with the main body of the high-frequency device by molding.
In the present invention, the switching spring portion is normally pressed and displaced by the elastic member in the vicinity of the central portion toward the connection plate portion,
The other end of the switching spring portion is in contact with the other end of the contact plate portion while the center portion is slightly displaced, and when the switching spring portion is pressed and displaced away from the connection plate portion during signal extraction, the center is When the displacement near the contact returns, the other end of the switching spring slides on the connection plate while maintaining the contact state with the other end of the connection plate, and then moves away from the other end of the contact plate. Is preferred.

[0007]

FIG. 1 is a schematic vertical sectional view of a center line of a high-frequency coaxial changeover switch according to an embodiment of the present invention.
FIG. 2 is a schematic horizontal sectional view taken along line AA of FIG. As shown in these figures, the switch 1 of the present invention
Is mainly composed of an insulating case 10, a terminal fixing cover 20, a switching spring 30, a contact plate 40, an elastic member 50, and a ground plate 60. The size of the switch cannot be read from the drawing, but is extremely small, about 3 mm (length) × 3 mm (width) × 2 mm (height). Hereinafter, each component will be described with reference to these drawings. During actual use, the insulating case 10 is fixed to a board (not shown) by soldering the ends of a switching spring, a contact plate and an earth plate. The insulating case 10 may be integrally formed by molding a resin such as plastic. The insulating case 10 has a substantially rectangular shape as a whole, and is provided with a depression 12 which is open upward and resembles a kind of a key hole shape, in particular, in the upper part thereof. The recess 12 is closed at the bottom, and
In the side part, only one side part (the direction of the bottom of the keyhole) 14 is open, and the other side part is closed. The elastic member 50 is accommodated in the recess 12 at the time of assembly.

The terminal fixing cover 20 is attached to the insulating case 10 so as to cover substantially the entire upper part of the insulating case. Similarly to the insulating case 10, the terminal fixing lid 20 may be integrally formed by molding a resin such as plastic. The terminal fixing lid 20 is formed in a substantially cylindrical shape as a whole, and is closed only at its ceiling. However, the ceiling does not completely close the terminal fixing lid, and the inspection needle (see “74” in FIG. 3) is located almost at the center.
Has an opening 22 for penetrating through. Even after the terminal fixing cover 20 is fixed to the insulating case 10, the operator can access the inside of the terminal fixing cover 20 from outside through the opening 22.
Further, the depression 12 of the insulating case 10 can be accessed. The lower portion 24 of the terminal fixing cover 20 has a shape similar to a key hole that exactly corresponds to the shape of the recess 12 of the insulating case 10. The size of the lower portion 24 is such that it fits exactly into the depression 12 of the insulating case 10. The terminal fixing lid 20 is attached to the insulating case 10 such that the lower portion 24 is fitted into the recess 12 of the insulating case 10. Lower part 24 of terminal fixing lid 20
Is completely fitted into the recess 12 of the insulating case 10,
The outer side surface of the lower portion 24 of the terminal fixing lid 20 and the inner side surface of the recess 12 of the insulating case 10 are engaged with each other, so that the recess 12 of the insulating case 10
Except for the lower part, almost all the inner side surfaces are closed by the lower part 24 of the terminal fixing lid 20.

The switching spring 30 and the contact plate 40 are provided so as to be fixed to the terminal fixing lid 20 described above. Each of these can be integrally formed by punching and bending from one metal material sheet. For each of the switching spring 30 and the contact plate 40, first, a single flat metal sheet is punched to form a large rectangular sheet 32.
(42), and one strip-shaped connection terminal 34 having a width smaller than that of the rectangular sheet 32 (42) and extending from the center of one side edge of the rectangular sheet 32 (42). (44) is formed. Thereafter, the metal sheet is converted into a rectangular sheet 32 (4
2), at the boundary between the strip-shaped connection terminals 34 (44) and at a predetermined portion of each of the strip-shaped connection terminals 34 (44) in parallel with this boundary, the strip-shaped connection terminals 34 (44) and the rectangular sheet 32 (42). ) Is bent at a right angle so that each end faces in the opposite direction to form a substantially “S” shape as a whole. However, the rectangular sheet 32 of the switching spring 30 is formed to be considerably longer than the rectangular sheet 42 of the contact plate 40. The rectangular sheet 32 of the switching spring 30 is to be easily displaced later by the inspection needle (see “74” in FIG. 3), while the rectangular sheet 42 of the contact plate 40 is fixed. This is for use in a state.

[0010] Terminal fixing lid 2 of switching spring 30 and contact plate 40
To fix the switching spring 30 or the contact plate 40, the terminal fixing lid 20 is molded with respect to the switching spring 30 or the contact plate 40, or the switching spring 30 is fixed to the molded contact terminal lid 20. The contact plate 40 may be press-fitted. The switching spring 30 and the contact plate 40 are each a rectangular sheet 3
2 and 42, the terminal fixing cover 2 near the boundary between the rectangular sheet 32 (42) and the strip-shaped connection terminal 34 (44).
0, it is fixed so as to be sandwiched from the upper side and the lower side. On the other hand, for the band-like connection terminals 34, 44, one of the terminal fixing lids 20 near the boundary between the rectangular sheet 32 (42) and the band-like connection terminals 34 (44) Fixed to be supported by the part. At this time, the contact area of the band-shaped connection terminal 44 of the contact plate 40 with the terminal fixing cover 20 is larger than that of the band-shaped connection terminal 34 of the switching spring 30, and the band-shaped connection terminal 44 is more completely fixed to the terminal fixing cover 20.

Switching spring 30 fixed to terminal fixing lid 20
Each of the rectangular sheets 32 and 42 of the contact plate 40 is disposed on the terminal fixing cover 20 such that a portion other than the fixing portion extends into the terminal fixing cover 20. Especially,
The rectangular sheet 32 of the switching spring 30 has a length sufficient to cover at least the center of the terminal fixing lid 20, and its tip is a free end that can be displaced vertically. On the other hand, the rectangular sheet 42 of the contact plate 40 is
It only has a length that extends slightly inside the
The tip is in a fixed state. These rectangular sheets 32 and 42 are in contact with each other at their distal ends inside the terminal fixing lid 20. Normal state, ie
This contact state can be maintained except during the inspection. As is clear from the above description and the drawings, the contact positions of these tip portions are on the side closer to the fixed portion of the contact plate 40, more specifically, on the side farther from the fixed portion of the switching spring 30.

In particular, an inverted U-shaped contact portion is provided at the tip of the rectangular sheet 32 of the switching spring 30. The inverted U-shaped convex portion 36 is provided with a rectangular sheet 42 of the contact plate 40.
In contact with the underside of the tip. The contact between the switching spring 30 and the contact plate 40 is made into a point (line) contact by the convex portion 36,
As a result, when dust enters between the switching spring 30 and the contact plate 40, dust is less likely to remain between them. Conversely, if such a convex portion is not provided, and if it is merely a flat tip portion, the contact point between the switching spring and the contact plate is brought into surface contact, and as a result, dust tends to accumulate, It can cause serious problems such as poor contact. Of course, instead of providing the switching spring 30 with the projection 36, a U-shaped projection may be provided below the distal end of the contact plate 40, or the projections may be provided on both of them. A point (line) contact may be provided.

The contact between the switching spring 30 and the contact plate 40 may be a natural contact where little force is applied when the elastic body 50 is not provided, or a spring directed upward to the switching spring 30. The bias contact may be maintained by applying a stress. Furthermore, it can be set in a non-contact state. In any case, in the present invention,
A bias contact can be made by the function of the elastic body 50. In particular, when bias contact is made by the elastic body 50 as in the present invention, the following advantages can be obtained in connection with the above-described problem of dust. That is, in the normal state, the switching spring 30 is pushed upward near the center portion thereof by the action of the elastic body 50 and is slightly displaced upward. The convex portion 36 is slightly in contact with the distal end of the contact plate 40 on the side far from the fixed portion of the contact plate 40, more specifically, on the side near the fixed portion of the switching spring 30. When the downward pressing by the inspection needle (see "74" in FIG. 3) is started near the center of the switch 30, the displacement of the switching spring 30 is returned to the original position. While maintaining the contact state with the contact plate 40, the contact plate 40 slides to a side slightly closer to the fixed portion of the contact plate 40, more specifically, to a side far from the fixed portion of the switching spring 30. The dust between the convex portion 36 and the contact plate 40 can be pushed out to the outside (wipe Grayed function). As described above, according to the present invention, even with the wiping function, it is possible to prevent poor contact due to adhesion of dust or flux.

When the terminal fixing cover 20 is fixed to the insulating case 10, one end of each of the strip-shaped connecting terminals 34, 44 is connected to the end 34 a, 44 a of the tip side of the insulating case 10. It is folded parallel to the boundary between the strip-shaped connection terminals 34 (44) and the rectangular sheet 32 (42) so that it can be located at the bottom. Each bent strip-shaped connection terminal 3
When fixing the switch to the board, the ends 34a, 44a of the 4, 44 are soldered to the corresponding positions of the board forming the high-frequency circuit. The high-frequency circuit is electrically disconnected in the vicinity of the position where the switch is disposed, and the terminal 34a is connected to the signal input side and the terminal 44a is connected to the signal output side of the disconnected circuit. Although the high-frequency circuit itself is in a disconnected state, the circuit is actually maintained in an electrically connected state through the contact between the switching spring 30 and the tip of the contact plate 40.

The elastic member 50 is provided in the recess 1 of the insulating case 10.
2 and is accommodated in a switch such that its upper part is covered by a rectangular sheet 32 of the switching spring 30. The elastic member 50 pushes the switching spring 30 disposed on the upper part thereof upward. This elastic body 50
A contact force is generated between the switching spring 30 and the contact plate 40 or the contact force between them is strengthened, and the switching spring 30 is separated from the contact plate 40 and is restored to make contact again. Power is maintained or strengthened. As a material of the elastic member 50, for example, rubber can be used. In the present embodiment, fluororubber is particularly used, but is not limited to this. Silicon can also be used as another rubber material. However, in the case of using the silicone rubber, the gas is generated during heating (for example, at the time of soldering) with normal silicon rubber, and there is a risk that the contact portion between the switching spring 30 and the contact plate 40 is contaminated. It is necessary to use degassed ones.

The shape of the elastic member 50 is substantially an abacus. Since this shape has a symmetrical shape as a whole, there is an advantage that when the elastic member 50 is accommodated in the recess 12 of the insulating case 10, there is almost no need to care about the accommodation direction of the elastic member 50. As described above, this advantage is very large because the actual size of the switch is as small as about 3 mm square. Other advantages will be described later. The ground plate 60 is assembled from the upper portion of the terminal fixing cover 20 so as to cover almost the entire switch. Similarly to the switching spring 30 and the contact spring, the ground plate 60 can be integrally formed by punching and bending one flat metal material sheet. Ground plate 60
Is assembled from the upper portion of the terminal fixing cover 20, the ground plate 60 is formed of the entire upper portion of the terminal fixing cover 20, a part of the side surface on which the strip-shaped connection terminals 34 and 44 are fixed, and the remaining side surface. Of the insulating case 10 and crimped into a concave portion provided on the bottom surface of the insulating case 10 (not shown) to fix the insulating case 10 and the terminal fixing cover 20 so as not to come off. The side surfaces of the switches to which the band-like connection terminals 34 and 44 are fixed are connected to the band-like connection terminals 34 and 44 by the ground connection terminals 66 similar to the band-like connection terminals 34 and 44, two of which are provided on each side. Covered in the same way as.
These ground connection terminals 66 are arranged so as to be separated from each other so as to sandwich the strip-shaped connection terminals 34 and 44 from both sides on each side surface. Earth connection terminal 66
Is bent and fixed to the substrate in the same manner as the band-like connection terminals 34 and 44. These ground connection terminals 66 are used to ground the switch and to fix it to the substrate.

When the ground plate 60 is fixed to the switch, two portions of the ground plate 60 (60a in FIG. 2) that cover the side surfaces other than the side surface to which the strip-shaped connection terminals 34 and 44 are fixed.
Are arranged at positions opposing each other, and the switching spring 30 is positioned between these parts so as to be always orthogonal to these parts. Such a positional relationship between the ground plate 60 and the switching spring 30 is very suitable for inspection of a high-frequency circuit. This is because even when the switching spring 30 is displaced in the vertical direction, the above-described positional relationship between the switching spring 30 and the ground plate portion 60a is maintained, so that the switching spring 30 is connected to the ground plate 60 (particularly, the portion 60a). Is small, and therefore, the impedance matching of the switch is hardly broken. The ground plate 60 has openings 6 corresponding to the openings 22 of the terminal fixing lid 20 so that the opening 22 provided in the terminal fixing lid 20 is not closed when the ground plate 60 is fixed to the switch.
4 are provided. These openings 22, 64 have approximately the same size. The inspection needle (see “74” in FIG. 3)
Through these openings 22, 64, the elastic member 50 housed in the depression 12 of the insulating case 10 can be accessed.

FIG. 3 shows a schematic vertical sectional view of the center line of the high-frequency coaxial change-over switch under test in the same manner as in FIG.
As shown in FIG.
The connection between the contact spring and the contact plate 40 is cut off, and at the same time, the switching spring 30 and the signal extracting member 70 are connected. The signal extraction member 70 is mainly composed of a cylindrical main body 72 connected to the ground plate, and the inspection needle 7 extended from the center to the outside.
4 Signal extraction member 70 is switch 1
The inspection needle 74 of the signal extracting member 70 is positioned between the terminal fixing lid 20 of the switch 1 and the
Reaches the switching spring 30 through the opening. Inspection needle 74
Further, a switching spring 30 extending inside the terminal fixing lid 20 is provided.
Is pressed downward against the restoring force of the elastic member 50, and further against the bias force generated when the switching spring 30 is subjected to a spring stress. When the switching spring 30 is displaced downward by the inspection needle 74, the connection between the switching spring 30 and the contact plate 40 is disconnected, and at the same time, the current of the switching spring 30 passes through the connection between the switching spring 30 and the inspection needle. 74, and as a result, the current can be extracted to the outside. The extracted current can be used for device inspection and the like.
Note that the distal end portion 76 of the main body 72 of the signal extraction member 70 has a convex shape so that the inspection needle 74 contacts the predetermined position of the switching spring 30, and the edge 62 of the opening of the earth plate 60 of the switch is correspondingly formed. It has a concave shape.

After the inspection, the signal extracting member 70 is separated from the switch. At this time, the switching spring 30 is surely restored to the original position by the restoring force of the elastic member 50 and, when a spring stress is applied to the switching spring 30, further by the bias force generated thereby. Therefore, according to the present invention, the contact state between the switching spring 30 and the contact plate 40 can be maintained even after the inspection is completed. According to the test results performed by the inventor, in the conventional switch having no elastic member as in the present invention, the contact between the switching spring 30 and the contact plate 40 can be obtained only seven or eight times. While the state could not be maintained, the switch of the present invention provided with the elastic member 50 was able to withstand more than 4000 inspections. Abacus beaded elastic member 5 of the present invention
Zero has proven to be very favorable for such an effect. Because, in this shape, since the corners of the outer peripheral area are removed, when the elastic member 50 is pressed by the switching spring 30, the displacement generated by the pressing is transferred to the preliminary space formed in the corners. Because it can be accepted. Furthermore, it is possible to displace the elastic member 50 with less force than when using the elastic member 50 that fills all of the storage portions. Further, in this shape, the contact point between the switching spring 30 and the elastic member 50 before pressing is the projection of the upper part of the abacus and the center of the switching spring 30. Therefore, the switching spring 30 and the contact plate 40 can be safely separated from each other. For example, if a simple columnar elastic member 50 is used, the central part of the switching spring 30 is pressed down when pressed,
In particular, the inverted U-shaped contact portion 36 of the switching spring 30 is displaced upward by a portion around the center of the cylinder, and the contact plate 4
There may be a danger that the connection between the zero and the contact portion 36 cannot be completely disconnected. However, the abacus beaded elastic member 50 of the present invention is used.
No such danger can arise.

As another preferred shape of the elastic member,
Some are shown in FIGS. 4A to 4E. A) in the figure,
The elastic members 50A and 50B shown in b) have a substantially symmetrical shape as a whole, and therefore can exert substantially the same effect as the shape of the abacus shown in FIGS. In addition, FIG.
The elastic members 50C, 50D, and 50E shown in e) cannot obtain the advantage at the time of storage, that is, the effect of not having to worry about the direction of storage, but have the other effect, that is, with a small force. It is sufficient to obtain the effect of displacing the elastic member and the effect that the end of the switching spring 30 is less likely to be displaced upward. Further, rubber is exemplified as the material of the elastic member, but is not limited to this. As a material other than rubber, a metal piece or a mold material can be used. For example, FIG.
The elastic member of (e) may be formed by bending a metal piece. However, when a metal piece is used, it is preferable to use a relatively low frequency (up to 3 MHz) or perform an insulation treatment so as not to affect the high frequency characteristics of the switch. FIG. 5 shows an example of the elastic member 52 using a molding material. This figure shows the cross section of the switch in the same manner as in FIG. As shown in this figure, the elastic member 52 can be provided integrally with the molding material of the switch body. It should be noted that the molding material may be inferior in strength and durability as compared with rubber or metal pieces, so that some care must be taken.

[0021]

By disposing the elastic member under the switching spring, a restoring force can be generated in the switching spring or the restoring force can be further strengthened, thereby enabling a large number of inspections. A tolerable switch can be provided. Further, dust accumulated between the switching spring and the contact plate can be pushed out by the wiping function of the switching spring.

[Brief description of the drawings]

FIG. 1 is a schematic vertical sectional view of a center line of a high-frequency coaxial changeover switch according to an embodiment of the present invention.

FIG. 2 is a schematic horizontal sectional view taken along the line AA of FIG.

FIG. 3 is a schematic vertical sectional view of a center line of the high-frequency coaxial changeover switch under inspection.

FIG. 4 is a diagram showing another preferred shape of the elastic member.

FIG. 5 is a schematic vertical sectional view of a center line of a high-frequency coaxial changeover switch according to an embodiment of the present invention in which an elastic member is a molding material.

[Brief description of reference numerals]

 DESCRIPTION OF SYMBOLS 10 Insulation case 12 Depression 20 Terminal fixing lid 22 Opening 24 Lower part of terminal fixing lid 30 Switching spring 32 Rectangular sheet 34 Band-shaped connection terminal 34a End 36 Reverse U-shaped convex part 40 Contact plate 42 Rectangular sheet 44 Belt Connection terminal 44a End 50 Elastic member 60 Ground plate 64 Opening 66 Ground connection terminal 74 Inspection needle

Claims (8)

[Claims] 1. A high-frequency changeover switch which is inserted and connected by dividing a high-frequency circuit of a high-frequency device, comprising: a switching spring portion having one end connected to one side of the high-frequency circuit to be divided; A connection plate portion having one end connected to the other side of the circuit, and the other end of the switching spring portion is always in contact with the other end of the connection plate portion to close the high-frequency circuit. However, at the time of signal extraction, in a high-frequency switching switch in which the switching spring portion is pressed and displaced to separate from the other end of the connection plate portion and divide the high-frequency circuit, to reinforce the spring property of the switching spring. A high-frequency changeover switch provided with an elastic member. 2. The high frequency changeover switch according to claim 1, wherein the elastic member is formed of a molded rubber material disposed below the changeover spring portion with respect to a predetermined position in the insulating housing of the high frequency changeover switch. 3. The high frequency changeover switch according to claim 2, wherein said molded rubber material has a shape capable of being elastically displaced without any trouble in said insulating housing when said switching spring portion is displaced by pressing. 4. The elastic member has a symmetric shape.
2. The high frequency changeover switch according to item 1. 5. The high-frequency changeover switch according to claim 4, wherein the elastic member has an abacus shape. 6. The high frequency changeover switch according to claim 1, wherein the elastic member is formed by bending a metal piece. 7. The high frequency changeover switch according to claim 1, wherein the elastic member is formed integrally with a main body of the high frequency device by molding. 8. The switching spring portion is normally pressed and displaced in the vicinity of the center by the elastic member toward the connection plate portion, and the switching spring portion is slightly displaced in the vicinity of the center. The other end of the contact plate portion is in contact with the other end of the contact plate portion, and at the time of signal extraction, the displacement near the central portion returns when the switching spring portion is pressed and displaced away from the connection plate portion, 2. An operation in which the other end of the switching spring portion slides on the connection plate portion while maintaining the contact state with the other end of the connection plate portion, and then moves away from the other end of the contact plate portion. 8. The high frequency changeover switch according to any one of items 1 to 7.