JPS5910001A - Dielectric filter - Google Patents

Abstract

PURPOSE:To produce a dielectric filter having a reduced variance among products, highly stable quality and a low cost with no control process virtually required, by connecting the conductor films of holes across a resonator to an input/output circuit via a capacitor and using the capacitor as an exciter for a mobile radio device. CONSTITUTION:Holes N-1, N-2-N-n which function as resonators are provided in parallel to a dielectric block 5. A conductor film 7 is formed on the inner surface of each hole, and at the same time a conductor film 6 is formed on the lower surface as well as both side surfaces of each hole respectively. A conductor film 7' which is unified with the film 7 is formed around the upper flat surfaces of holes N-1 and N-n at both ends. A flat capacitor 10 is set at the upper part of the holes N-1 and N-n respectively. The electrode at one side of the capacitor 10 is connected to the film 7' by soldering, and the electrode at the other side is connected to an input/output connector 4 and then directly to the conductor films of the holes N-1 and N-n respectively. As a result, the coupling quantity between the input and the output of this dielectric filter is decided only by the capacity of the capacitor 10 and is stable regardless of the processing accuracy of the block 5.

Description

[Detailed description of the invention] ra+ Technical field of invention The present invention relates to improvements in dielectric filters.

(h) Behind the Technology - Dielectric fillers are widely used in portable and in-vehicle radio equipment called Kin'i Mobile @ Line, which are small, have low loss, and have little change in characteristics due to temperature changes. .

(()) An example of a conventional dielectric filter of this type is shown in Fig. 1 ('). (A) in Fig. 1 is a cross-sectional view, N
In the same figure, 5 is a planar cross section (2) of the part M, where 5 is a section where the loss of one body is small, for example, 1-1.
The number of holes N-1, N-2,...N-n is 11
It is set up C. In addition, the entire inner surface of the dielectric block 50, both sides 8 of the top surface 1, and the holes N-1, N-2, . . . The conductor film 6, 8 is metalized with etc. and the conductor [7]
! Formation 1t1. -ζ゛There is.

On the upper surface of the induction valve 1 and the cock 5, near both ends, there are V holes (exciter holes 8, 1, etc.) 1, and a metal example is the excitation of a copper rod for 9 months.

1) 1.1 y
Ri5 has 17 sides, and both sides of the ε-paralyze are in close contact with a box-shaped F-body l made of, for example, aluminum τ' horns.
U IW1 is covered with -7 T2 to maintain the desired air gap.

Adjustment screws 3 are installed in positions I of the -7 holder 2 corresponding to the holes N-1, N-2, and N-3. 7: The IJ vibrator 9i is connected to the input/output coifter 4 attached to the side plate of the housing l.

Then, each hole N-1 of the dielectric 5
゜N-2,...N-n (...) Since the two sides are open and the bottom surface is connected to the casing l through the conductor membrane 6, the hole N-1゜.
...The filter shown in Figure 71, which is a resonant element that resonates at a frequency with a total length of N-n, has good temperature characteristics because it is made of dielectric flock. Resonant element force 54 rest 7 is formed tl, 1. Since it has a single hole, it is resistant to vibration and is suitable for in-vehicle wireless devices.

However, the dielectric block 5 is formed by a sintering method,
Since the cost is low, the diameter of the exciter hole 8 and the distance between the exciter hole 8 and the holes N-1, )IN-n vary. Therefore, variations occur in the connection weight of input and output. Also, is there an excitation body 9 made of a metal rod in the excitation body hole 8? However, the amount of coupling varies depending on the contact state of the excitation body 9.

Completely eliminate this problem - "-Z, no V 11 shu'μm 4: Noronono 5 burnout Q15'
There is also a method of machining a thousand legs, but this method is expensive and not common. From then on, all the complicated work A was done, such as adjusting the length of the metal rod of the excitation body 9 one by one.

Also, let's apply this exciter 9 to a duplexer that can be used for antennas.・5
If so, there is a problem that the phase changes depending on the contact α state of the exciting body 9.

tdl OBJECTS OF THE INVENTION An object of the present invention is to provide a dielectric main filter that eliminates S, which is one of the problems of the conventional art.

Structure of the Invention In order to achieve this object, the invention connects the 7.1 body membrane of the hole at both ends of the resonant element and the input/output circuit via a capacitor, and by making the capacitor gold exciter ≧, The input/output coupling amount is determined by the capacitance of the capacitor (-C).
It's something new.

[fl Embodiment of the Invention Figure 2 is an embodiment of the present invention, (A) is a cross-section 1hI diagram, (q
is a cross-sectional view of the chain ridge N-74 portion in (a), FIG. 3, and FIG.

In Fig. 2 VC, the dielectric flock 5 has holes N-s, N-2,...N-11, which serve as resonant elements, arranged in parallel. A conductor film 7 is formed on the inner surface, and a conductor film 6 is also formed on the bottom 1t-1 and both side surfaces.

A conductor film 71 having a shape of 11ff is provided integrally with the conductor film ``1'' around the holes N-1 at both ends and the upper plane of the hole N-n.

lO is an XF-type condenser → J, and one is placed at the top of hole N-1° and hole N-n, and one of them! 1. The exposed conductor 7
The front poles of No. 11 and 11, which are soldered to N8, are connected to the input and output coils and the lid 4, respectively.

In this way, the combination → No. 10 is directly connected to hole N-1, hole N-
Since the r & conductor membranes of n are connected, the input/output coupling weight of the dielectric filter ζ is determined only by the capacitance of the capacitor 1o, and is stable without being affected by the processing accuracy of the dielectric 5. are doing.

In the third m, the contact 1) J'lO is fixed on the upper plane of the dielectric block 5 near both ends with adhesive, for example, and -10,000! The poles are lined up with the conductor 11 in the shape of a hoop, and the holes IX
J-t, the solder explodes on the conductor film 7 of the hole N-n,
The other electrode is connected to the input/output coifter 4.

This method of installing the condenser lo is simpler than the one shown in FIG. 2. In FIG. 4 VC, hole N-1. A metal rod 12 made of copper, for example, whose diameter is approximately equal to the hole diameter is fitted into the hole N-n &, and a capacitor 10 is placed on the upper end surface of the metal rod 12.
The -10,000 electrodes are fixed by soldering, and the other electrodes are respectively connected to the input/output connectors 4.

The capacitor 10 is made of such a thin piece of plastic, and the capacitor 10 can be attached at the same time with a reliable and simple device. As a whole, the total cost is +7, which means that the variation between products is 1 less, the quality is less, and the amount of adjustment required is almost 1 ton, and the cost is too high. This dielectric filter has excellent practical effects.

[Brief explanation of the drawing]

Figure 1 shows a conventional dielectric filter (A) is a front cross-sectional view, control 'A) is a cross-sectional view of the chain 4-M section, and Figure 2 is an embodiment of the present invention; (A) is a cross-sectional view of a conventional dielectric filter. Front sectional view, (C71 is the chain diagram of (A), 1 is the housing, 2 is the lid, 3 is the adjustment screw, 4 is the input/output connector, 51- is the dielectric block, ft, 7°7
' is a conductor film, Ri- is an excitation body hole, 9 is an excitation body, 10 is a nodenser, IN is a conductor, 1:N, ':i gold parrot, N-1
゜N-2,...N-n is a hole? show. To substitute Tomoshi Hiroshi Matsuoka 1R Haku 1 figure - Me 3 figure

Claims (1)

[Claims] ill Upper and lower surfaces? A conductive film is formed on the bottom surface of a rectangular parallelepiped dielectric block in which a plurality of holes that move forward and backward are arranged in parallel, and a conductor film is formed on both sides and the inner surface of the core. A Z-dielectric filter is characterized in that the conductive film is connected to the input/output circuit through a capacitor (7).
4. The dielectric material according to claim 1, characterized in that it is placed at the upper end of the rod.