JPH0421313B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a connection structure for microwave circuits, and particularly to a connection structure for connecting connected units or microwave components.

[Conventional technology]

Conventionally, microwave circuits were generally called MIC (Microwave
It was often realized as a type of integrated HIC (Hybrid Integrated Circuit). Also recently, MMIC
(Monolithic Microwave Integrated Circuit)
There has also been an increase in the number of circuits integrated on semiconductor substrates, called ``electronics''. In any case, these unit circuits are generally enclosed in a shield case in order to prevent deterioration in reliability due to the environment, electromagnetic shielding, and prevention of excitation of unnecessary propagation modes. In actual applications, a plurality of these cased components are used in combination. In that case, connections between components are required, but the structure that has generally been used is to make the RF terminal part a coaxial line structure,
The connection structure was such that the conductors of the RF terminals were led out to the opposite side by penetrating the thick plate, and the RF terminals were connected using a microwave strip line.

In other words, as shown in Figure 5 a and b, case 1
The lead wire of the RF terminal 12 is connected to the coaxial line 15 between the connected units 11 housed in the microstrip board 14 through an insertion hole drilled in the microstrip board 14, and soldered onto the conductor of the microstrip line. They were connected by attaching.

[Problems to be solved]

Conventional connection structures have the following disadvantages: First, they require access from both the top and bottom during assembly, which is time-consuming.Second, they require soldering, which takes time and is not suitable for assembly work. There is a drawback that the discontinuity of the line changes depending on the amount of solder, and the characteristics fluctuate. Third, it is possible to reduce the electrical discontinuity at the transition point from the coaxial line connected to the RF terminal section to the microstrip line section. This has the disadvantage that impedance mismatch becomes noticeable especially at high frequencies.Fourthly, the cavity of the microstrip line becomes large, which may excite unnecessary modes or cause other problems. It has the disadvantage that it often causes unnecessary coupling with the circuit.

[Means for solving problems]

In order to solve the above-mentioned conventional problems, the present invention includes a plate spring-shaped center conductor supported by a dielectric material in a groove bored in a case serving as an outer conductor of the line; It is an object of the present invention to provide a novel microwave circuit connection structure including a fixed contact disposed at an RF terminal of a connected component that is in contact with the tip.

To this end, the present invention provides a flexible center conductor in the shape of a leaf spring, a support member made of an insulating material that supports the center conductor, a fixed contact disposed on an RF terminal of a connected unit, and a center conductor that supports the center conductor. and a groove-shaped outer conductor that accommodates a support member and a fixed contact, and the connected units are connected by contact between the center conductor and the fixed contact. The present invention provides a connection structure for a microwave circuit.

〔Example〕

Next, the connection structure of the microwave circuit of the present invention will be specifically explained with reference to the accompanying drawings.

FIG. 1a is a longitudinal cross-sectional view of an embodiment of a connection structure for a microwave circuit according to the present invention. 11 is a connected unit, and 12 is its RF terminal pin. Reference numeral 1 denotes a center conductor shaped like a leaf spring, and 2 and 2A support members for the center conductor 1, which are made of an insulating material. 3 is a fixed contact attached to the RF terminal 12 of the connected unit 11. The fixed contact 3 may be formed integrally with the RF terminal 12, or may be formed separately. It is desirable that the entire center conductor 1 and fixed contact 3 or at least the portions where they contact each other be plated with gold. Reference numeral 5 denotes a post formed on the support member 2 for positioning the storage depth with respect to the groove 6 bored in the case 6A made of a conductor.

FIG. 1b is a plan view with the connected unit 11 removed. Reference numeral 4 denotes a positioning guide hole for the fixed contact 3, which is provided in the support member 2 of the center conductor 1.

FIG. 1c is a sectional view taken along the line A-A in FIG. 1a, and
The relative positional relationship between the center conductor 1, fixed contact 3, and groove 6 is shown.

Fig. 2 shows an example of mounting in which connected units 11 are connected in series, and Fig. 2a is a cross-sectional view of the second unit.
Figure b is a plan view thereof. Fixed contact 3 attached to the center conductor 1 and the RF terminal of the connected unit 11
A connection is made by contact. This will be explained with reference to FIG.

FIG. 3a illustrates the central conductor 1 in a state in which the fixed contact 3 is not inserted. center conductor 1
The elastic deformation of is zero or small. In FIG. 3b, the fixed contact 3 is inserted and the center conductor 1 is pushed down, and its displacement generates a constant contact pressure. This constant contact pressure is very important. If it is too weak, a contact failure will occur, and if it is too strong, the center conductor may deform beyond the stress limit.

FIG. 4 is an exploded perspective view of an embodiment of the microwave circuit connection structure of the present invention. Reference numeral 7 denotes a metal plate for completely shielding the connection line, which is covered with the center conductor support member 2 and the connected unit 11 is attached thereon. This completely shields the connecting line portion.

The microwave circuit connection structure of the present invention has stable characteristics with little line discontinuity and little variation in the connection state.

The reason why line discontinuities can be reduced is because the structure is simple and the discontinuities are small. That is, the line exiting the pin of the RF terminal 12 of the connected unit 11 is converted into a so-called trough line at the fixed contact 3. The trough line has a structure in which a circular central conductor is placed within parallel ground plates, and the electromagnetic field distribution is concentrated on both ground plates. The line is connected from the trough line to a central conductor 1 shaped like a leaf spring, and the central conductor 1 shaped like a leaf spring is a so-called edge line in which the electromagnetic field is concentrated at the edge. Therefore, from the fixed contact 3 to the leaf spring-shaped central conductor 1
The electrical connection to is made smoothly.

Next, we will explain why the connection has little variation and is highly stable and reproducible. In order to improve stability, it is sufficient to keep the relative positional relationship of the components constituting the transmission line constant, including the outer conductor. In the microwave circuit connection structure of the present invention, the support member 2 of the center conductor 1 plays a role in accurately providing relative positional relationship. In other words, the post 5 has a shape and size that allows it to fit into the groove 6 of the case 6A without any gaps.
The position of the center conductor 1 in the depth direction of the groove 3 is determined accurately. The center conductor 1 is supported by supporting members 2, 2
It is accurately positioned and supported by A. There are various methods in addition to the method using two pins 16. Since the fixed contact 3 attached to the RF terminal 12 of the connected unit 11 is inserted into the insertion hole 4 provided in the center conductor support member 2, the relative positional relationship between the fixed contact 3 and the center conductor 1 can also be maintained accurately. As described above, since the relative positional relationship of the parts involved in the connection is maintained accurately, there is very little variation in characteristics.

The connection structure of the microwave circuit of the present invention disposes the connection line in the groove 6, which has a significantly smaller volume than the microstrip line of the conventional connection structure, and therefore excites discontinuities (mainly surface wave mode). It is very good because it does not mix with other signals. However, since there are cases where a large amount of isolation is required, such as when the transmitting circuit and the receiving circuit are configured close to each other, the metal plate 7 is provided as a shielding member. Therefore, the microwave circuit connection structure of the present invention achieves an extremely good connection state.

〔Effect of the invention〕

As is clear from the above, since the present invention is assembled by dropping from above, there is no need for assembly work on both mounting surfaces as in conventional connection structures, and the assembly work time can be shortened. This has the effect of lowering the product price. The present invention has the effect of speeding up assembly work because soldering work is not required for connection, and also has the effect of reducing variations in line discontinuity and stabilizing performance. The present invention has the effect that since the connection structure is simple, line discontinuity can be reduced and good characteristics can be achieved. Since the present invention employs a transmission line structure consisting of a leaf spring-like center conductor and a groove, most of the electromagnetic field on the line is concentrated at the edge of the leaf spring-like center conductor, and the center conductor is centered within the groove. This has the effect of maintaining the characteristic impedance of the line constant even if the conductor bends and changes its position. Therefore, in the present invention, by bringing the fixed contact attached to the RF terminal of the component into contact with the leaf spring-like center conductor, the amount of deformation of the leaf spring-like center conductor due to variations in the dimensions of the components is reduced. This has the effect that the characteristic impedance of the line can be kept constant even if it changes, thereby realizing a stable connection.

Since the connecting line is formed in a small groove, the present invention has the effect of not excitation of unnecessary modes, and conversely can reduce the influence from other sources, especially when a metal plate for shielding is arranged. The effect of bastards can be noticeable.

[Brief explanation of drawings]

FIG. 1a is a longitudinal cross-sectional view of one embodiment of the connection structure for a microwave circuit according to the present invention, FIG. 1b is a plan view of FIG. 1a with the connected unit removed, and FIG. Fig. 2a is a sectional view of the same mounting example, Fig. 2b is a plan view of the same, Fig. 3a, b
4 is an exploded perspective view of the contact connection, and FIGS. 5a and 5b are diagrams showing the connection structure of a conventional microwave circuit. DESCRIPTION OF SYMBOLS 1... Center conductor, 2, 2A... Support member, 3... Fixed contact, 4... Guide hole, 5... Post, 6... Groove, 7...
Metal plate, 11... connected unit, 12... RF terminal.

Claims (1)

[Claims] 1 A flexible center conductor shaped like a leaf spring, a support member made of an insulating material that supports the center conductor, a fixed contact provided at the RF terminal of the connected unit, and a fixed contact between the center conductor and the support member. a groove-shaped outer conductor for accommodating a contact, and the connected units are connected by contact between the central conductor and the fixed contact. connection structure.