JPH0132616B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical field to which the invention pertains] The present invention relates to a switch used in a microwave band or a millimeter wave band. In particular, the present invention relates to switches having mechanical contacts without using semiconductor elements such as diodes or transistors.

[Description of prior art]

A conventional actuator for a microwave switch having mechanical contacts uses an electromagnetic actuator driven by solenoid operation. When this electromagnetic actuator was used to drive a microwave switch, some performance was obtained, but
There was heat generation due to solenoid coil copper loss, power consumption was large, and there was a limit to switching speed.

Since microwave switches are mainly used for switching between active and standby communication devices, high reliability is required. Furthermore, with the recent trend toward lower power consumption of communication devices, the large power consumption of electromagnetic actuators has become a problem. On the other hand, as the signals handled by communication devices have shifted from analog signals to digital signals, it has become a problem that switching times of 10 to 30 milliseconds are required when electromagnetic actuators are used. . Furthermore, since the fewer the signal dropouts when switching between the active and standby communication devices, the better, there is a need for a microwave switch that has a fast switching time.

On the other hand, semiconductor switches used as conventional switches are suitable for high-speed switching, but have drawbacks such as the inability to provide a large amount of cut-off attenuation when disconnected.

[Purpose of the invention]

The present invention eliminates the above-mentioned drawbacks, and the switch part has a large cutoff attenuation when disconnected, and
It is an object of the present invention to provide a microwave switch which has a short switch operation time and low power consumption of a driving section.

[Key points of the invention]

The present invention provides a fixed contact connected to a center conductor of a high-frequency signal terminal, a movable center conductor that takes two positions with respect to the fixed contact, a contact state and an open state, and a position of the movable center conductor that changes. In the ultra-high frequency switch, the movable center conductor is configured to have a shape that, when in contact with the movable center conductor, becomes a center conductor that is well aligned with the outer conductor, and the means for changing the position has one end attached to the movable center conductor. a drive rod formed of an electrically insulating material with the other end extending outside the external conductor; a leaf spring with its center approximately attached to the other end of the drive rod; and a piezoelectric element that gives deflection to the leaf spring. and an actuator including a ceramic element.

[Explanation based on examples]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be explained based on the drawings. FIG. 1 is an external view showing the structure of this embodiment device in a state where the contacts are made, with a part cut away. Moreover, FIG. 2 is an outline drawing showing the structure of this embodiment device in a contact broken state.
A portion is shown broken away.

First, the configuration of this embodiment device will be explained based on FIG. 1 and FIG. 2. The device of this embodiment is composed of a switch section 10 and an actuator section 20. Here, the switch section 10 includes a main body 11,
It is composed of a main body cover 12, a coaxial connector 13, a shell 14, an insulator 15, a central conductor 16, a fixed contact 17, a movable central conductor 18, and a drive rod 19. The shell 14 also serves as the outer conductor of the microwave signal transmission path, and is a member that fixes the coaxial connector 13. The center conductor 6 is fixed with an insulator 9, and the drive rod 19 is an electrical insulator and is a member that fixes the coaxial connector 13. It carries a conductor 18. The actuator section 20, which is a feature of the present invention, includes a piezoelectric ceramic element 21, hinges 22 and 23, a lever 24, and a leaf spring 2.
5 and a stopper 26, the piezoelectric ceramic element 21 is fixed to the main body 11 by the stopper 26, the lever 24 is pivotally connected to the piezoelectric ceramic element 21 by hinges 22 and 23, and the leaf spring 25 is attached to the lever 24.
The drive rod 19 is held near the center of the leaf spring 25.

Next, the operation of this embodiment device will be explained based on FIGS. 1 and 2.

FIG. 1 shows a state in which a voltage is applied to the piezoelectric ceramic element 21 and the element is stretched. In this state, the displacement of the piezoelectric ceramic element 21 is converted to the displacement of the lever 24 via the hinge 22, and the lever 24 is displaced so that its tip rotates around the hinge 23. As shown in the figure, since the distance between the hinges 22 and 23 is short and the length of the lever 24 is long, the amount of displacement of the piezoelectric ceramic element 21 is increased. When the distance between the left and right levers 24 is narrowed, the leaf spring 25 attached between the tips of the levers is buckled and bent downward in FIG. The amount of displacement magnified by the lever 24 is further magnified by the spring 25, and the drive rod 19 attached to the leaf spring 25 is pushed downward. When the drive rod 19 is pushed, the movable central conductor 18 carried by it and the fixed contact 1
7 comes into contact and becomes a make state.

In this state, the microwave signal transmission path becomes a transmission path from the coaxial connector 13 through the movable center conductor 18 to the other coaxial connector 13, and the cross-sectional dimensions of each part are adjusted so that the characteristic impedance of this transmission path becomes the specified value. It is determined. Therefore, the voltage standing ratio of the entire system can be suppressed to a small value.

Next, FIG. 2 shows a state in which no voltage is applied to the piezoelectric actuator. In this state, the piezoelectric ceramic element 21 is not extended, so the space between the pair of levers 24 is widened, and the leaf spring 25 is , since no force is applied in the direction of buckling it,
The leaf spring 25 is stretched and its deflection is reduced.
The drive rod 19 attached thereto is also in a pulled up state, and the movable central conductor 18 carried by the drive rod 19 is in close contact with the inner wall of the main body cover 12. At this time, between the two fixed contacts 17, the movable center conductor 18 is in close contact with the outer conductor wall. In this state, the structure between the fixed contacts 17 is equivalent to that of a cutoff region waveguide, so the electromagnetic wave energy propagating between the fixed contacts 17 is attenuated exponentially, and a large cutoff attenuation can be obtained. . In order to ensure this close contact state, the dimensions of the drive rod 19 are determined so that the leaf spring 25 is not in a completely free state and a slight amount of displacement remains.

Although a lever mechanism is used as part of the mechanism for magnifying the displacement of the piezoelectric ceramic element described in this embodiment, the present invention can also be practiced using other displacement magnifying mechanisms.

〔Effect of the invention〕

As explained above, in the present invention, since a piezoelectric ceramic element is used in the actuator section, the driving power is extremely low, and in the steady state when the switch operation is completed, power is required to maintain this state. Since the structure is such that it does not occur, it has the effect of extremely reducing power consumption.

In addition, actuators using piezoelectric ceramic elements have a high response speed for converting electrical energy into mechanical energy, so the limit switching time of electromagnetic actuators using solenoids, which is about 10 milliseconds, takes about 0.5 milliseconds. This has the effect of significantly shortening the time.

Further, the present invention has a simpler structure than a switch using an electromagnetic actuator, and
The structure has fewer mechanical sliding parts, which has the effect of increasing operational reliability.

Furthermore, since the present invention can be constructed thinly, the installation space can be saved.

Therefore, if the present invention is applied to a microwave communication device, the effect will be significant.

[Brief explanation of drawings]

FIG. 1 is an external view showing the structure of the device according to the present invention in a contact-made state. FIG. 2 is an external view showing the structure of the device according to the present invention in a contact broken state. 10...Switch part, 11...Main body, 12...
Body cover, 13... Coaxial connector, 14... Shell, 15... Insulator, 16... Center conductor, 17
... Fixed contact, 18 ... Movable center conductor, 19 ...
Drive rod, 20... actuator section, 21... piezoelectric ceramic element, 22, 23... hinge, 24
... Lever, 25 ... Leaf spring, 26 ... Stop.

Claims (1)

[Claims] 1. A fixed contact connected to a center conductor of a high-frequency signal terminal, a movable center conductor that takes two positions with respect to the fixed contact, a contact state and an open state, and a position of the movable center conductor. The movable center conductor is configured to be a center conductor that is well aligned with the outer conductor when in contact with the movable center conductor, and the means for changing the position of the movable center conductor a drive rod formed of an electrically insulating material with one end attached to the conductor and the other end extending outside the outer conductor; a leaf spring with its approximate center attached to the other end of the drive rod; and an actuator including a piezoelectric ceramic element that provides a high frequency coaxial switch.