DK144495B - COACIAL TYPE QUARTER RESONATOR - Google Patents

Description

(φ

(19) DENMARK

t β (12) PUBLICATION <10 144495 Β

DIRECTORATE OF THE PATENT AND TRADEMARKET SYSTEM

(21) Application No. 992/78 (51) Int.CI.3 H 01 P 7/04 (22) Filing Date 6 Mar. 1978 (24) Race day 6 Mar 1978 (41) Aim. available Nov. 10; 1978 (44) Posted 15 Mar 1982 (86) International application # - (86) International filing day - (85) Continuation day - (62) Master application no -

(30) Priority May 9, 1977, 771 620, NO

(71) Applicant IVAN BACH, 4990 Søndel ed, NO.

(72) Inventor Same.

(74) Clerk of the Office of Industrial Excellence v. Svend Schønning.

(54) Coaxial quarter wave resonator = type.

The present invention relates to a coaxial-type quarter-wave resonator in which the free end of the central conductor is temperature compensated with respect to its fixed end by a combination of elements of material with different coefficient of thermal expansion.

Resonators of this kind are known in which the central conductor consists of two telescopic-like movable tubes, one of which forms the free end of the central conductor and with the outer end connected to the compensating elements. Upon expansion or contraction due to temperature variations, the outer end will be fixed relative to the fixed end of the central conductor formed by the inner end of the second tube so that the compensation in itself works satisfactorily. , but the sliding contact between the two tubes means a variable contact resistance between the two tubes, which affects the stability of the resonator.

The object of the invention is therefore to provide a quarter-wave resonator of the kind mentioned at the outset by which this disadvantage is eliminated.

This is achieved according to the invention by a quarter-wave resonator, of the type mentioned initially, which is characterized in that the free end of the central conductor, which is connected to its fixed end by means of temperature compensating elements, is provided with transverse breakthroughs in a flexible pattern. which allows it to expand and contract, depending on the temperature, between the fixed end and that of the fixed relative to the fixed end, the fixed free end of the central conductor.

The compensating elements according to the invention can advantageously consist of a central rod of steel alloy having an expansion coefficient of 0.0000115, one end of which is threadedly connected to the fixed end of the central conductor and the other end of which is connected to one end of a coaxial aluminum alloy ambient tubes having an expansion coefficient of 0.000023, the other end of which is connected to one end of a coaxial steel alloy tubing having an expansion coefficient of 0.0000115, the other end of which is connected to the free end of the central conductor.

For roughly adjusting the frequency of the resonator, the central conductor can consist in a known manner of telescope-like movable tubes, according to the invention, one tube is fixed at one end and at the other end carries a conically acting clamping connection with the other tube, which forms the free end of the central conductor and is provided with the flexible breakthrough pattern.

An embodiment of the invention will be described in more detail below with reference to the drawings.

Pig. 1 shows an axial section through an exemplary embodiment of a quarter-wave resonator according to the invention.

Pig. 2 shows a section of FIG. 1, in which section the flexible pattern at the free end of the central conductor is shown.

The embodiment shows a quarter wave resonator of the UHF and SHF coaxial type, with a closed outer conductor consisting of a resonator housing 15 and a lid 10, e.g. of aluminum, and an inner central conductor 4, consisting of two telescopically slidable tubes, 3 HU95 of which one end of the tube, which is fixed in the resonator, is fixed centrally in the lid 10, which has a threaded central bore which occupies a central steel alloy rod 1 with a coefficient of expansion of 0.0000115. The outer end of the rod 1 is connected to the outer end of a coaxial surrounding aluminum alloy tube 2 with a heat expansion coefficient of 0.000023, the other end of which is connected to the inner end of a coaxial surrounding steel alloy tube 3 with a heat expansion coefficient of 0. 0000115 and the outer end of which is connected to the free end of the central conductor 4. The material properties of the compensating elements 1, 2, 3 cause the central conductor to have a fixed length L. within a very large temperature range, to allow the free end of the central conductor to retain the desired fixed distance L from the lid 10 within the desired large temperature range, the outer part of the central conductor is provided with a pattern 14 of transverse breakthroughs which makes it flexible, that is, the patterned portion can be compressed and expand again. without any change in transition resistance. The second tube in the central conductor 4, which is provided with the pattern that makes it flexible.1, is connected to the first tube by means of a conical clamp connection 13 to coarsely adjust the resonant frequency of the resonator. The rod 1 enables fine tuning of the resonator, its upper end being connected to rotatable and lockable members 5,6,7,9.

As indicated in FIG. 1 is an oscillator or amplifier 8 by means of a coupling loop 12 extending through an opening 11 in the lid 10 coupled to the interior of the resonator.