DE1068775B - Switching device for microwave ovens - Google Patents

Description

The invention is concerned with a switching device for microwave ovens and is particularly suitable for switching from operating to Reserve device.

In radio relay technology, it is customary to use the company radio to increase operational reliability Assign reserve radio device, which is automatically switched into the radio line in the event of failure. In addition In addition to other switchings in the intermediate frequency and low frequency, it is especially a high frequency switch required, which switches the transmitter or receiver in the line to the antenna. In the case of directional radios in the cm wave range, the inputs and outputs of the devices and the antenna cable are constructed with hollow tubes, and there is therefore a need for a switch within the Ductile pipe system. For this purpose, a number of technical solutions are known that are mechanically moving hollow pipe parts work. All of these arrangements have the disadvantage that they are extensive and require expensive constructions and because of the large mass of the moving parts relatively long Umsrihaltzeiten to have. In the case of a switching device for microwave devices, in particular for switching from the operating to the reserve device is therefore proposed according to the invention by the movement a small conductive pin in the course of the permanently installed waveguide or hollow tube oscillating circuits to block or open for the flow of energy of the electromagnetic waves. By using them at the same time of ferrite circulators (directional forks) switching these pins on and off causes the switching.

The invention thus brings about the essentials compared to the previously known changeover switches Advantage that moving hollow tube parts are completely avoided and the switching process only the movement of a small and light pen in the course of the permanently installed hollow pipes. Due to the simultaneous Use of ferrite circulators (direction forks) will take the place of an elaborate one and slow mechanical switchover between three terminals a simple and fast on-off switching set between two terminals, which in the circuit according to the invention in a switchover is implemented.

Fig. 1 shows such an arrangement. The two radio devices FG ₁ and FG ₂ contain the transmitters S ₁ and S ₂ on the frequency f _t and the receivers B ₁ and B ₂ on the frequency Z ₂ . The radio device FG ₁ is the operating device and FG ₂ the reserve device. A ferrite circulator Z ₁ or Z _{2 is} assigned to both devices, within which the energy is passed on in the sense of the indicated rotary pointer. At the switching device
for microwave ovens

Applicant;

Telefunken GmbH,
Berlin NW 87, Sickingenstr. 71

Dipl.-Ing. Erwin Willwacher, Backnang (Württ.) _R
has been named as the inventor

Circulator Z ₁ , the transmitter S ₁ (at connection 11), the receiver E ₁ (at connection 31), the antenna ^ (at connection 21) are connected, while the fourth connection 41 is connected to the connection 22 of the circulator Z. Sender S ₂ and receiver B ₂

The reserve device is connected to the connections 12 and 32 of Z ₂ , and the last connection 42 of Z ₂ is closed with the absorber R without reflection. The switchover between S ₁ and JT ₂ or E ₁ and E ₂ takes place with short-circuit devices K ₁ and K ₂ , which essentially each consist of a pin s , which is moved with the aid of a magnet system and either into the hollow tube L ₁₁ or L ₃₁ is immersed so far that a short circuit occurs, or is pulled out of the hollow tube, so that the energy can flow through unhindered.

For normal operation (with FG ₁ in operation) the short-circuit devices K ₁ and K _{2 are} open. The transmitter energy from S ₁ runs over the line X ₁₁ to the connection 11 of the circulator Z ₁ and is conducted within Z ₁ to the connection 21 and to the antenna A. The connections 31 and 41 remain decoupled due to the non-reciprocal Ciculator effect and thus receive no energy. The path of the received energy from the antenna via connection 21 to connection 31 and from there to receiver E ₁ is corresponding. In this case, the circulator connections 11 and 41 are decoupled and do not absorb any received energy. Since the connection 41, which leads to the reserve device, receives neither transmitter nor receiver energy,

4-5, the reserve device can remain firmly connected via the hollow pipes and Z _{2 without any repercussions from FG 2} to FG ₁ occurring. In particular, no short-circuit interference is _{required in lines L 12 and L 32.} Transmitter, S ₂ and receiver E _{2 of} the reserve device are of course, z. B. by switched off operating voltages, put out of operation.

Now falls z. B. the transmitter S ₁ off, the reserve _{transmitter S 2} is activated by switching on

909 648/294

Claims (5)

and at the same time the magnet system of K1 is excited, so that a short circuit, ie total reflections, occurs in L11. The energy from S2 then runs from connection 12 to 22, from there via the connecting line between Z2 and Z1 to connection 41 and arrives inside Z1 to connection "1" and into line L11. Since there is almost total reflection in L11, almost all of the energy is thrown back into the Ciculator Z1 and arrives at antenna A via connection 21 Short circuit established. The received energy passes from connection 21 to connection 31, is totally reflected in line L31 and fed via connection 41 to 22 and finally to 32 and the reserve receiver E2. The system described thus allows the independent reserve switching of transmitter and receiver. Another, even more advantageous embodiment of the invention makes use of the fact that in most cases band filters are available for selection at the transmitter output and receiver input, and therefore relocates the switching process leading to total reflection to an oscillating circuit of the multi-stage hollow tube filter. Fig. 2 shows such a circuit in principle. In this case, the hollow tube filters F1, F2, F3 and F4 are three-circuit and assumed to have resonant circuits C11, C21, C31, etc. The short-circuit or switching devices K1 and K.- are attached in the first hollow tube resonant circuits of the radio device FG1. If the state of total reflection is to be generated in L11 or L31, the pin s with the magnetic drive system is inserted so far into the HoM pipe circuit C11 or C12 that a sufficiently large detuning of the circuit occurs. This has the advantage that the switching path of the pen can be significantly shorter than in the case of FIG. 1 and consequently the switching time is shorter. In addition to the simple switching, the arrangements described so far also have the property that reflections due to incorrect adaptation of the antenna do not affect the devices, since the two circulators lead these returning waves into the absorber resistor R. This is explained using an example: The wave generated by the transmitter S1 runs via the circulator Z1 to the antenna A, and let a wave reflected by A run back on the antenna line. This reflected wave of frequency ft does not return to terminal 11 and transmitter S2, but is directed to 31. There it is totally reflected on the receiver filter tuned to the frequency / and passed on to connection 41 and the circulator Zg. Then it passes from connection 22 to connection 32, is reflected again at the receiver filter and finally comes to connection 42 and the absorber resistor R. If this separating property is dispensed with, the invention can be carried out in an even simpler form with only one circulator. This arrangement is shown in FIG. The filters F1 and F2 and F3 and F4 are e.g. B. via i / 4 lines, combined into a branching switch, which combines a transmitter and a receiver. Then only the two connecting lines L1 and L3 remain, which are connected to the connections 1 and 3 of the circulator. At the connection 2 is the antenna A, the connection .4 is terminated with a short-circuit plate P totally reflective. The two holding devices K1 and K2 are now distributed between the devices FG1 and FG2, K1 is located in the filter F1 of the transmitter ^ 1, K., in the filter F4 of the receiver E2. The filters F2 and F3 therefore do not contain any switching device. When the device FG1 is in operation, K1 is switched to transmission and K2 to reflection. The transmitter .5 \ is connected to antenna A via L1, connection 1, connection 2. The connection 3 is decoupled. The received energy comes via connection 2 to 3, is reflected in L3 at the filter F4 detuned by K2, runs back in 3 and arrives at connection 4. There the energy is reflected again at the shorting plate P and comes via connection 1 to the filter F2 and the Receiver F1. If the transmitter Jv1 fails, z. B. by appropriate relay arrangements, the transmitter ^ automatically brought into operation by switching on the operating voltages and at the same time the short-circuit device K1 switched to reflection. The energy from S2 then passes via connection 3 to connection 4, is reflected there, comes to connection 1, is reflected there again and reaches antenna A via connection 2. switched, and the received energy finds its way to receiver F2 via terminals 2 and 3. If the direction of rotation of the circulator runs in a different sense than assumed in FIG. 3, then the filters F1 and F4 remain without a switching device. That is, the two filters F2 and F3 are equipped with conductive pins. Patent claims: 1. Switching device for microwave devices, especially for switching from operating to the reserve device, characterized in that the movement of a small conductive pin in the course of the permanently installed waveguide or HoM tube oscillating circuits, these for the energy flow of the blocks or opens electromagnetic waves, whereby by simultaneous use of ferrite circulators (Direction forks) the on-off switching of these pins causes the switching. 2. Switching device according to claim 1, characterized in that a first radio device is connected with its transmitter and receiver each with an arm of a circulator, with in these two connections each have a short-circuit pin insertable; that another arm of the circulator leads to the antenna and that the fourth arm of the circulator with an arm of a second circulator is connected to the transmitter or receiver of a second on each of a further arm Radio device is connected directly, and that its fourth arm with an absorber is reflection-free is completed. 3. Switching device according to claim 2, characterized in that the short-circuit pins in the filters of the transmitter output and the receiver input are relocated. 4. Switching device according to claim 1 ,. characterized in that the two radios switched to the common antenna via a single circulator and the transmit and receive filters to each radio set via Λ / 4 lines a branch switch are combined, the short-circuit pins in the filters of the first transmitter and second receiver or in the filters of the first receiver and the second Transmitter lie. 5. Switching device according to one of the preceding claims, characterized in that the short-circuit pins are controlled so that in the event of failure of a device automatically on the corresponding Reserve device is switched over. 1 sheet of drawings ® 909 645/294 11:59