JPS60180036A - Microwave switch - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical field to which the invention pertains] The present invention relates to a microwave switch suitable for a microwave band communication device. In particular, the present invention relates to a microwave switch having mechanical contacts with low power consumption and heat generation, high reliability, and short switching time.

(Description of the prior art) Among the switches in the microwave band, the ones most in demand are those used for switching between active and standby communication equipment.Switches used for such purposes are low-loss and , isolation (leakage attenuation between unconnected terminals)
Since a large value is required, switches using semiconductors as switching elements are not used due to performance problems, and switches with mechanical contacts are often used. Microwave switches with mechanical contacts use electromagnetic actuators to drive the contacts. Because electromagnetic actuators have a relatively long history, they have achieved a certain degree of performance and reliability, but they are not without problems, especially with the recent miniaturization and reduction of power consumption of communication equipment, as well as the need for maintenance. Conventional microwave switches, which use electromagnetic actuators as the drive source, have already been unable to make significant improvements in response to the need for higher reliability due to the trend toward free switching.

More specifically, power consumption and heat generated by the copper coil of the electromagnetic actuator become a problem.

There is also a limit to the reliability of operation due to the complexity of the electromagnetic actuator itself and the contact drive mechanism that transmits displacement and force from the actuator to the switching part of the microwave switch. Such switches are required to have extremely high reliability because they are inserted into a common path for switching between active and standby communication devices.

Furthermore, the shortcoming of electromagnetic actuators is that their switching times are long because their speeds are not fast, which is becoming a major problem as the digitalization of communication systems has expanded in recent years. Digital systems have a problem with signal loss when switching.

(Objective of the Invention) An object of the present invention is to provide a microwave switch which improves the above-mentioned drawbacks, has low power consumption, low heat generation, is highly reliable, and has significantly shortened switching time. .

[Features of the invention]

The present invention includes two first fixed contacts that are selection terminals, one second fixed contact that is a common terminal located between the two first fixed settings, and each provided between the fixed contact and the two first fixed contacts,
two movable central conductors that short-circuit one of the second fixed contacts and the two first fixed contacts; and two drive rods that respectively carry the two movable central conductors. A microwave switch equipped with an electrostrictive element whose length is displaced by an externally applied voltage, two lever arms that magnify the displacement of this electrostrictive element, and a microwave switch provided between these two lever arms. The present invention is characterized in that it includes a flexible beam-like member, and a transmission spring whose both ends are engaged with the two drive rods and whose approximately center portion is interlocked with the central portion of the beam-like member.

[Explanation based on examples]

Embodiments of the present invention will be described with reference to the drawings. 1st
The figure is a plan view of a microwave switch according to an embodiment of the present invention, with the cover of the portion for switching microwave signals removed. The second side is a diagram showing another switching state of the microwave switch shown in FIG. 1. Figure 3 is A of Figure 1.
- It is a figure showing the A cross section. FIG. 4 is a partially enlarged perspective view of the microwave switch of the present invention. In FIG. 1, the main body case 1 switches the microwave signal at the part where switching is actually performed (hereinafter referred to as the microwave switching part).
- Also serves as the outer conductor of the lithopline.

The center of the three fixed contacts 7 corresponds to a common terminal, and as a switch, a switching operation is performed by the one connected to the common terminal and either one of the left and right fixed contacts 7. When the movable center conductor 8 is in contact with the fixed contact 7, it functions as a strip line for transmitting signals. The drive rod 9 carries and drives the movable center conductor 8 and is made of an electrically insulating material. The drive rod 9 is fitted into a guide 1itb provided on the main body 1, and is arranged so as to slide smoothly. The electrostrictive actuator 20 uses a ceramic electrostrictive element 21 as a driving source.

The displacement of the ceramic electrostrictive element 21 causes the lever arm U to rotate around the hinge 23 via the hinge 22.
The displacement is magnified by a kind of lever principle. The electrostrictive actuator 20 is fixed to the main body case 1 of the microwave switch with screws 27. A leaf spring 25 is attached to the tip of the lever arm 24, and a transmission leaf spring 26 extends left and right from near the center of the leaf spring 25. It is connected to rod 9.

In the embodiment shown in FIG. 1, the tip of the transmission leaf spring 26 is inserted into a hole 9a provided at the end of the drive rod 9, thereby making the connection.

Next, the operation of the microwave switch of the present invention will be explained. FIG. 1 shows one state of the microwave switch of the present invention, which corresponds to one state of the electrostrictive actuator 20. FIG. 2 shows another state of the switch, which corresponds to another state of the electrostrictive actuator 20. A microwave switch performs a switching operation by alternately switching between the states shown in FIG. 1 and FIG. 2. First, in the state shown in FIG.
No voltage is applied to. The handling spring 25 is almost fully extended in a straight line. The transmission leaf spring 26 pulls the drive rod 9 upward in FIG. Therefore, on the left side of FIG. 1, the movable central conductor 8 carried by the drive rod 9 is pressed against the inner wall of the outer conductor.

On the other hand, on the right side of FIG. 1, the movable center conductor 8 is in contact with both the fixed contacts 7 of the ii1 terminal and the right selection terminal.

Here, the movable central conductor 8 needs to be brought into contact with the wall surface on the non-connection side and with the fixed contact 7 on the signal connection side with appropriate pressure. The reason for this is explained below.

First, the reason wall contact is necessary is to obtain large isolation. If the movable center conductor 8 is not grounded, it becomes a transmission path that has low impedance but can propagate real energy, so that great isolation cannot be obtained. Most ideally, the movable central conductor 8 should be in contact with the inner wall of the outer conductor over its entire length. In the embodiment shown in FIG. 1, the movable central conductor 8 is brought into contact with the grounding protrusion 1a protruding from the inner wall of the outer conductor without making full-surface contact. This method is simple at relatively low frequencies.

On the other hand, contact pressure on the conductive side is also required. However, the larger the value, the better, and the optimum value must be determined by taking into consideration driving power, durability, reliability, etc.

The wall surface contact pressure and the contact point contact pressure explained above are given by the displacement of the transmission leaf spring 26 and the leaf spring 25.

To reverse this switch, electrostrictive actuator 20
A voltage is applied to the electrostrictive element 21, and the electrostrictive element 21 is expanded in the vertical direction in FIG. When the electrostrictive element 21 expands, it lifts the hinge 22, so that the lever arm 24 rotates about the hinge ridge. Since the ratio of the distance between the hinge 22, which is the center of rotation and the point of force application of the electrostrictive element 21, and the distance between the hinge 22 and the tip of the lever arm 24 is large, the displacement of the electrostrictive element 21 increases. As a result, the distance between the tips of the pair of lever arms 24 moves in the direction of narrowing (the direction of moving closer to each other). When the distance between the lever arms 24 is narrowed, the leaf spring 25 sandwiched therebetween buckles and bends, pushing the drive rod 9 via the transmission leaf spring 26.
When the leaf spring 25 pushes the drive rod 9, the second movable center conductor 8
The one on the left side of the figure is brought into contact with both the fixed contacts 7 of the common terminal and the selection terminal on the left side, and the two fixed contacts 7 are closed.

The movable center conductor 8 on the right side is grounded to the outer conductor. The contact pressure and the wall surface contact pressure are transmitted from the electrostrictive actuator 20 by the transmission leaf spring 26 and the leaf spring 25.

In FIG. 3, fixed contact 7 is connected to coaxial connector 2. In FIG. The end of the fixed contact 7 may be connected directly to the circuit to be switched, but as shown in Figure 3, it is guided to the coaxial connector 2 and connected to another circuit to be switched or a communication device via the coaxial connector 2. In some cases, it may be done.

FIG. 4 is a partially enlarged perspective view of the transmission leaf spring 26 and the leaf spring 25. FIG. Here, the transmission leaf spring 26 is welded to the leaf spring 5 as a separate member, but both leaf springs 5 and 26 may be integrally formed from one plate material.

Further, the leaf spring 26 does not have to be plate-shaped; for example, it can be a linear spring. Although the leaf spring δ may not be plate-shaped, it is preferable to use a leaf spring in order to easily obtain the directionality.

The microwave switch of the present invention is not limited to microwaves, but can of course be used at lower frequencies, such as VHF '11. Also, various modifications are possible. Shape of movable center conductor 8, fixed contact 7, drive rod 9
Various guiding methods and transformations can be considered. For example, by relatively firmly engaging or attaching the drive rod 9 to the transmission leaf spring 26, the drive rod 9 can be guided only by the groove on one side instead of being guided by grooves on both sides of the main body as in the embodiment. is also possible.

The electrostrictive actuator 20 may also be of any type as long as it deflects the leaf spring 25 (which also does not need to be a leaf spring if it is a flexible member). For example, the type proposed in Japanese Patent Application No. 58-049248 Mechanical Amplification Mechanism 1 can be used.

〔Effect of the invention〕

As explained above, the present invention uses an electrostrictive actuator to open and close contacts, so that in a steady state, power consumption is extremely low, and therefore, the amount of heat generated is also low. In addition, the switch structure has a high response frequency for the electrical-mechanical energy conversion system, so a switching time that is more than an order of magnitude faster (less than 0.5 m5ec) can be obtained compared to a conventional microwave switch using a Denken actuator. It has excellent effects. Furthermore, it has the advantage of simple structure and high reliability. Therefore, it greatly contributes to lowering the overhead power costs of communication devices, and by shortening the switching time, it is possible to expand the usage to the Ik-mode, where digital communication is considerably increasing.

[Brief explanation of drawings]

FIG. 1 is a plan view of a microwave switch according to an embodiment of the present invention. FIG. 2 is a diagram showing another switching state of the microwave switch shown in FIG. 1. FIG. 3 is a sectional view taken along the line AA in FIG. 2. FIG. 4 is a partially enlarged perspective view of the microwave switch of the present invention. DESCRIPTION OF SYMBOLS 1... Main body case, 2... Cover, 7... Fixed contact, 8... Movable center conductor, 9... Drive rod, 2o...
・Electrostrictive actuator, 21... Ceramic electrostrictive element, 22.23... Hinge, 24... Lever arm,
25... Leaf spring, 26... Transmission leaf spring. Patent Applicant NEC Corporation Agent Patent Attorney Nao Ide Takaatsu 3 Sonomoto 4 Drawing procedure amendment 1 Display of 1 case per month 1988 Patent Grant II No. 36818 2 Name of the invention My 70 Shiv I-7 3 Relationship with the person who makes the amendment 1 month Applicant 4, agent 5 Date of amendment order (Number of inventions increased due to spontaneous oil stop 9 6111ij 1- None + 1
1. The scope of claims shall be amended as shown in the attached sheet. (2) In the specification, page 4, line 4, 1 switching time is also corrected to ``]-switching time''. (3) ``Correct the fixed setting j to 1 - fixed contact - 1'' on page 4, line 15 of the specification. power consumption]. [Separate] [Claims] (1) A common terminal I provided between the two first fixed contacts which are selection terminals and the first fixed origin of the nymph. a second fixed contact, and each provided between the second fixed contact and the two first fixed contacts,
two movable center conductors that short-circuit between this second fixed contact and either one of these two first fixed contacts; A microphone with a stick) and a wave switch, an external force 1
1. Does the length change depending on the applied voltage? Lj, a strain element, two rehaar Js that magnify the displacement of the electrostrictive elements, a flexible beam-like part provided between this one bar arm, and G. Both ends are engaged with T drive rods, and the beam-shaped portion (A
A microphone 1-1 wave sui-nochi, characterized in that it is provided with a transmission spring interlocking with approximately the center or the center portion of the microphone.

Claims (1)

[Claims] +11 Two first fixed contacts that are selection terminals, one second fixed contact that is a common terminal provided between the two first fixed settings, and this second fixed contact. and the two first fixed contacts, and short-circuit between the second fixed contact and either one of the two first fixed contacts. In a microwave switch equipped with a movable center conductor and two drive rods respectively supporting the two movable center conductors, an electrostrictive element whose length is displaced by an externally applied voltage; two lever arms that magnify the displacement of the beam; a flexible beam-shaped member provided between these two lever arms; both ends of which are engaged with the two drive rods; A microwave switch characterized in that the center includes a transmission spring interlocked with the center portion.