JPH1086U - High frequency relay - Google Patents

Abstract

(57) [Summary] To provide a high-frequency relay having excellent high-frequency characteristics. A fixed terminal is inserted into a plurality of through holes provided in a base, and a gap between an inner peripheral surface of the through hole and the fixed terminal is filled with an insulator made of a fluororesin. The pair of fixed terminals 3 is opened and closed by a movable contact piece 9. The area of the portion of the fixed terminal 3 protruding from the surface of the base 1 is formed to be larger than the cross-sectional area of the portion inserted into the through hole 4, and the movable contact piece 9 is movable in the longitudinal direction of the fixed terminal 3. I have. Since the insulator 5 has a low dielectric constant, the diameter of the through hole 4 is reduced, and the distance between the fixed terminals 3 is reduced, so that the electric path between the fixed terminals 3 is shortened. Also,
The fixed terminal 3 has a large contact area with the movable contact piece 9 so that the contact resistance is reduced.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to a high-frequency relay for a printed circuit board.

[0002]

[Prior art]

 FIG. 2 shows a conventional high-frequency relay, in which an outer shell is composed of a flat metal base 1 and a box-shaped metal cover 2 covering the base 1. Fixed terminals 3 are arranged in a straight line on both sides of the base 1, and each fixed terminal 3 is arranged at the center of the through hole 4 so as to penetrate the base 1. Each fixed terminal 3 is insulated from the base 1 by an insulator 5 ′ arranged in the through hole 4. An electromagnet section 6 is disposed at a substantially central portion of the base 1 with an insulating material interposed therebetween. A pair of fixed terminals 3 is opened and closed by a contact spring 7 driven by the electromagnet section 6.

[0003]

[Problems to be solved by the invention]

 In such a high-frequency relay, a hermetic seal type printed board relay in which a metal base 1 is used, the fixed terminal 3 is surrounded by an insulator 5 ′, and the whole is covered with a metal cover 2 is used. It was said to be excellent in properties. However, there is a problem that impedance matching is poor and good frequency characteristics cannot be obtained. On the other hand, some devices use a coaxial connector to match the impedance.However, when the coaxial connector is used, the pitch between the terminals becomes large, so that the electric path inside the high-frequency relay becomes long and the insertion loss increases. Occurs.

The present invention has been made in view of the above points, and has as its object to provide a high-frequency relay having excellent high-frequency characteristics.

[0005]

[Means for Solving the Problems]

 The present invention provides a metal base provided with a plurality of small-diameter through holes, a plurality of fixed terminals which are inserted into the respective through holes and project from the back surface of the base to a printed circuit board, and a pair of fixed terminals. A movable contact piece movable between a position for connecting the movable contact piece and a position away from the fixed terminal, an electromagnet portion for driving the movable contact piece, and at least a contact portion between the fixed terminal and the movable contact piece with the base. A metal cover coupled to the base so as to surround it; and a fluororesin insulator filled between the fixed terminal and the inner peripheral surface of the through hole. The fixed terminal protrudes from the surface of the base. The area of the portion is formed larger than the cross-sectional area of the portion inserted into the through hole, and the movable contact piece is movable in the longitudinal direction of the fixed terminal. According to this configuration, since the fixed terminals connected to the printed circuit board and the base are insulated by the fluororesin insulator having a low dielectric constant, the diameter of the through hole provided in the base can be reduced. As a result, it is possible to reduce the distance between the fixed terminals and downsize the base. As a result, the electric path inside the high-frequency relay is shortened, and the insertion loss can be reduced. In addition, by forming the area of the portion of the fixed terminal projecting from the surface of the base to be larger than the cross-sectional area of the portion inserted into the through hole, and making the movable contact piece movable in the longitudinal direction of the fixed terminal, The contact area between the movable contact piece and the fixed terminal can be increased, and the insertion loss can be reduced.

[0006]

[Embodiment of the invention]

 Hereinafter, embodiments of the present invention will be described with reference to the drawings. In FIG. 1, a base 1 is made of metal, and three through holes 4 are drilled in a longitudinal direction of a central portion, and the fixed terminal 3 is arranged to penetrate on a center line of each through hole 4. . An insulator 5 is filled between each fixed terminal 3 and the inner peripheral surface of each through hole 4. A card 8 is arranged between each pair of adjacent fixed terminals 3 so as to be freely movable in parallel, and each card 8 holds a movable contact piece 9 which is conductive and springy. Each of the movable contact pieces 9 is integrally formed with the card 8 by a single piece, and is brought into contact with the fixed terminal 3 so that the movable contact piece 9 is moved between the fixed terminal 3 at the center and the fixed terminal 3 at each end. They are connected via the Internet. A part of the fixed terminal 3 and the movable contact piece 9 are covered by the base 1 and the metal cover 2. That is, the cover 2 has a recess 10 formed on the lower surface, and the cover 2 is coupled to the base 1 so that a part of the fixed terminal 3 and the movable contact piece 9 are accommodated in the recess 10. . Ground contacts 12 are formed on the inner lower surface of the cover 2 corresponding to the tip of the movable contact piece 9, and the ground terminal 13 electrically connected to the ground contact 12 protrudes from the lower surface of the base 1. An electromagnet section 6 (see FIG. 2) for driving the card 8 is disposed on the cover 2. When both cards 8 are driven by the electromagnet unit 6, the space between each pair of fixed terminals 3 is opened and closed, respectively.

The upper end of the fixed terminal 3 protruding from the upper surface of the base 1 is formed to have a diameter larger than that of the portion inserted into the through hole 4. That is, the area is larger than the cross-sectional area of the portion inserted into the through hole 4. Further, the movable contact piece 9 is movable in the longitudinal direction of the fixed terminal 3, that is, in the vertical direction in FIG. 1, and can contact the upper surface of the fixed terminal 3. The two cards 8 are opened and closed by moving the pair of fixed terminals 3 through the movable contact pieces 9 with the up and down movements being opposite to each other. Here, since the area of the upper end portion of the fixed terminal 3 is relatively large, a contact area with the movable contact piece 9 can be secured, and the contact resistance can be relatively small. That is, the insertion loss is reduced.

The insulator 5 for insulating the metal base 1 and the fixed terminal 3 is made of a fluorine resin. Fluororesins have characteristics of a low dielectric constant (dielectric constant ε = 2 to 3), a small dielectric loss tangent, and a high heat resistance. The characteristic impedance Z _{0 at} a portion corresponding to the through hole 4 is expressed by Expression 1.

[0009]

(Equation 1)

Here, D ₁ is the outer diameter of the fixed terminal 3, D ₂ is the inner diameter of the through hole 4, and ε is the dielectric constant of the insulator 5. The characteristic impedance Z ₀ can be expressed by a simple formula such as Equation 1 because the fixed terminal 3 has a circular cross section and a constant diameter inside the through hole 4 and the through hole 4 has a circular cross section and a constant diameter. This is because the fixed terminal 3 is inserted through the through hole 4 on its center line. As is apparent from Equation 1, the characteristic impedance Z ₀ increases as the dielectric constant ε of the insulator 5 decreases. Although fixed terminal 3 can be regarded as a constant value because the lower limit by the intensity defined upper limit the implementation of the print plate is defined, the through-hole 4 is larger inside diameter D ₂ than the fixed terminal 3 yo rather, this larger the inner diameter D ₂ according to Equation 1 the characteristic impedance Z ₀ is increased Togawakaru. That is, assuming that the characteristic impedance Z ₀ is constant, the smaller the dielectric constant ε of the insulator 5, the smaller the inner diameter D ₂ of the through hole 4 can be. Therefore, a low dielectric constant and a fluorine resin can be reduced inner diameter D ₂ of the through-hole 4 by using as the insulator 5, resulting in the distance between the fixed terminal 3 small to Rukoto is capable Become. That is, the electric path passing through the movable contact piece 9 is shortened, which leads to a decrease in insertion loss. In addition, since the fluororesin has a smaller dielectric loss tangent than PBT (polybutylene terephthalate) generally used as an insulating material, the insertion loss can be reduced from this point as well.

As is apparent from FIG. 1, the distance between both ends of the through hole 4 (the thickness of the insulator 5 in the longitudinal direction of the fixed terminal 3) is different from the distance between the fixed terminal 3 and the upper surface of the base 1. Since the amount of protrusion is sufficiently small, the influence on the characteristic impedance of the portion of the fixed terminal 3 protruding toward the upper surface of the base 1 (that is, the portion exposed in the air) can be reduced. That is, the amount of protrusion of the fixed terminal 3 on the upper surface side of the base 1 is relatively small, and the movable contact piece 9 contacts the fixed terminal 3 at a position near the base 1, so that the fixed terminal 3 projects on the upper surface side of the base 1. The impedance of the part where it is located has little effect on the overall impedance. This means that it is possible to obtain a characteristic impedance that substantially matches the design value according to Equation 1, and it is easy to set the characteristic impedance.

[0012]

[Effect of the invention]

 The present invention provides a metal base provided with a plurality of small-diameter through holes, a plurality of fixed terminals which are inserted into the respective through holes and project from the back surface of the base to a printed circuit board, and a pair of fixed terminals. A movable contact piece movable between a position for connecting the movable contact piece and a position away from the fixed terminal, an electromagnet portion for driving the movable contact piece, and at least a contact portion between the fixed terminal and the movable contact piece with the base. A metal cover coupled to the base so as to surround it; and a fluororesin insulator filled between the fixed terminal and the inner peripheral surface of the through hole. The fixed terminal protrudes from the surface of the base. The area of the part is formed larger than the cross-sectional area of the part inserted in the through hole, and the movable contact piece is made movable in the longitudinal direction of the fixed terminal. Low dielectric between Since the insulation is provided by the fluororesin insulator, the diameter of the through-hole provided in the base can be reduced, and as a result, the distance between the fixed terminals can be reduced, and the base can be downsized. Therefore, there is an advantage that the electric circuit inside the high-frequency relay is shortened and the insertion loss can be reduced. In addition, the area of the portion of the fixed terminal projecting from the surface of the base is formed larger than the cross-sectional area of the portion inserted into the through hole, and the movable contact piece is movable in the longitudinal direction of the fixed terminal. In addition, there is an advantage that the contact area between the movable contact piece and the fixed terminal can be increased, and the insertion loss is reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

2A and 2B show a conventional example, wherein FIG. 2A is a cutaway plan view, FIG. 2B is a transverse sectional view, and FIG. 2C is a longitudinal sectional view.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Base 2 Cover 3 Fixed terminal 4 Through-hole 5 Insulator 6 Electromagnet part 9 Movable contact piece

Claims (1)

[Utility model registration claims] 1. A metal base provided with a plurality of small-diameter through-holes, a plurality of fixed terminals inserted into the respective through-holes and projecting from the back surface of the base and connected to a printed circuit board, and a pair of fixed terminals A movable contact piece that is movable between a position connecting the movable contact piece and a position away from the fixed terminal, an electromagnet portion that drives the movable contact piece, and at least a contact portion between the fixed terminal and the movable contact piece between the base. A metal cover coupled to the base so as to surround the same, and a fluororesin insulator filled between the fixed terminal and the inner peripheral surface of the through hole, and protruding from the surface of the base at the fixed terminal. A high-frequency relay in which the area of the portion is formed larger than the cross-sectional area of the portion inserted into the through hole, and the movable contact piece is movable in the longitudinal direction of the fixed terminal.