JPH0215387Y2 - - Google Patents

Description

[Detailed description of the invention] [Technical field of the invention] The invention relates to a lumped constant variable delay line that combines a coil made of a conductor wound and a capacitor.
This invention relates to an improvement of a small variable delay line that has good productivity and can finely switch the delay time.

[Prior art and its problems]

Conventionally, this type of variable delay line was constructed so that a capacitor was connected between the connection point of adjacent coils among multiple coils and the ground, and the delay time was changed by switching the connection points of these coils. There is something.

In order to switch the connection point of the coil, the variable delay line configured in this way has a fixed contact connected to the connection point formed on a terminal board such as a printed circuit board,
When the movable contact is slid over this fixed contact,
Easy to switch.

However, when the variable delay line is miniaturized, it becomes difficult to handle the lead wires that connect the coil connection point and the fixed contacts, and not only do they come close to each other, but also adjacent fixed contacts also come close to each other.

As a result, productivity does not improve, and the lead wires protruding from the individual fixed contacts tend to short-circuit between the fixed contacts, causing problems in terms of both productivity and quality.

[Purpose of invention]

The present invention was developed to solve these conventional drawbacks, and it is a small, inexpensive, adjustable lead wire that connects the coil connection point and fixed contact, which is easy to handle, and has good productivity and quality. The purpose is to provide a delay line.

[Structure and effect of the idea]

In order to achieve this objective, the present invention connects a plurality of coils made of wound conductors in series at a predetermined pitch, and connects adjacent among the coils to a plurality of fixed contacts constituting a fixed contact row formed on a terminal board. Connect the connection point of the coil with a lead wire, connect a capacitor between the connection point and ground, and alternately repeat single contact with each fixed contact among the fixed contacts and double contact with each other adjacent fixed contacts. In addition to disposing a movable contact means that moves with the terminal plate, an uneven portion for positioning the lead wire is formed at the end of the terminal plate.

With this configuration, it is easy to handle the lead wires that connect the connection points of adjacent coils and the fixed contacts, improving productivity and quality, and making it possible to reduce the size and price. .

[Example of idea]

The details of the present invention will be explained below.

1 and 2 are a front sectional view and a side sectional view showing an embodiment of the present invention.

In the figure, a rod-shaped non-magnetic bobbin 1 with a rectangular cross section has a plurality of coils 2 wound in series and coaxially at a predetermined pitch in a single-layer solenoid-like manner with a plurality of coils 2, forming an inductance element 3. ing.

The inductance element 3 has support portions 4 protruding from both side surfaces at both ends of the non-magnetic bobbin 1.
It is placed on the inner bottom of the casing 5 and placed horizontally within the casing 5.

A terminal plate 6 as shown in FIG. 4 is placed on the support portion 4 located above the horizontally placed inductance element 3 so as to pass over the coil 2.

The terminal board 6 has a plurality of fixed contacts 8 formed on the main surface of a thin and elongated insulating plate 6a, perpendicular to and parallel to the axial direction of the insulating plate 6a, and these fixed contacts 8 form a fixed contact array. 9 are configured.

A plurality of V-shaped cuts 10 are continuously formed on the end surface of the insulating plate 6a along the axial direction. A cut groove 11 is formed in each fixed contact 8 from a direction opposite to the cut 10 to the middle of each fixed contact 8.

Note that these fixed contacts 8 are preferably formed by photoetching or the like from a printed circuit board, and the notches 10 are formed by press working.

A connection point between adjacent coils 2 and a capacitor 12 are connected to the end of each fixed contact 8 on the notch 10 side. Connection between the connection point of the coil 2 and the fixed contact 8 is performed by twisting and leading out the lead wire 2a from between the adjacent coils 2 and passing through a V-shaped notch 10.

The capacitor 12 is made of a thin and elongated dielectric plate 12a.
A ground electrode 13 is formed on the main surface of the casing 5, and a plurality of capacitance electrodes 14 are formed at predetermined intervals on the main surface opposite the ground electrode 13. A ground electrode 13 is connected to the tip and is supported so as to extend above and parallel to the inductance element 3. The capacitive electrode 14 of the capacitor 12 and the fixed contact 8 are connected by a lead wire 16.

In this way, the inductance element 3 and the capacitor 12 are combined to form a lumped constant delay line.

Input/output terminals 17, 18 and input/output ground terminals 19, 20 are implanted at the bottom of the housing 5.

The support plate 15 is connected to the input/output ground terminals 19 and 20, and the fixed contact 8 at one end of the fixed contact array 9 is connected to the output terminal 18.

A conductive plate 21 connected to the input terminal 17 is attached to the opening of the housing 5 so as to close the opening. A recess 22 facing the inductance element 3 is formed in the conductive plate 21 along the inductance element 3 .

A spring holder 24 is disposed between the recess 22 and the fixed contact row 9 so that its upper portion protrudes from a sliding groove 23 formed in the recess 22 along the fixed contact row 9.

A sliding spring 25 curved into an arcuate shape is housed within the spring holder 24 . The sliding spring 25 has an end slidably in contact with the conductive plate 21, and has a movable contact 26 formed into a curved bulge.
is elastically brought into contact with both the individual fixed contacts 8 in the fixed contact row 9 and the adjacent fixed contacts 8, and constitutes movable contact means.

Then, if the knob 27 attached to the upper part of the spring holder 24 is moved along the sliding rod 23, the sliding spring 25 will move between the individual fixed contacts 8 and the movable Contact 2
It moves on the fixed contact row 9 while repeating single contact with the fixed contact 6 and double contact with both the adjacent fixed contacts 8 and the movable contact 26.

Therefore, the input terminal 17 is connected to any fixed contact 8 via the conductive plate 21, the sliding spring 25, and the movable contact 26.

Note that since the movable contact 26 is biased against the fixed contact 8, as the spring holder 24 moves,
The depressions are repeated between the fixed contacts 8 and between the cut grooves 11 in the fixed contacts 8. Therefore, an operational feeling such as a clicking sound can be obtained, and the contact between the movable contact 26 and the fixed contact 8 can be ensured.

In the variable delay line configured in this way, the lead wire 2a connecting between the connection points of adjacent coils 2 and the fixed contact 8 is connected to the V-shaped notch 10 provided in the terminal plate 6 on which the fixed contact 8 is formed. Since the position is regulated by the variable delay line, even if the shape of the variable delay line is miniaturized, the lead wire 2a can be easily handled, short circuits between fixed contacts are less likely to occur, and productivity and quality are improved.

Moreover, the V-shaped notch 10 can be easily manufactured by press working, and the mold for press working is also easy to manufacture and inexpensive, making it possible to suppress an increase in price.

Next, the operation of the variable delay line of the present invention will be briefly considered using an equivalent circuit diagram.

FIG. 3 is an equivalent circuit diagram showing the variable delay line shown in FIG. 1 including an external circuit.
6 indicates a single contact state.

In the variable delay line shown in FIG. 1, as shown in FIG. 3, a plurality of inductances L and capacitors of capacitance C are alternately connected in a ladder shape, and a coupling coefficient a is established between the inductances L in adjacent sections. The present is shown in an induced m-type configuration.

Then, the delay time td in one section is td=√(1+2)・...(1), and the characteristic impedance Ro is: becomes.

Additionally, a terminating resistor Ro is connected between the output terminals 18 and 20.
is connected, and a resistor Ro is also connected between the other end of the inductance element 3 and the ground (not shown in FIG. 1). The pulse signal source PG has an output impedance of Ro/2, and input terminals 17 and 19.
connected between.

The input signal from the pulse signal source PG is transmitted to the conductive plate 21
It is input to the fixed contact 8 via the sliding spring 25, etc.
The energy is divided into two and propagated both to the left and right from the input point. In other words, the signal propagated to the right is 1
After a delay time obtained by multiplying the delay time td for the section by the number of sections on the right side from the input point, it is output to the output terminals 18 and 20, and is absorbed by the terminating resistor Ro as a load.

Therefore, by moving the knob 27 shown in FIG. 1 and sliding the movable contact 26, the delay time of the output signals from the output terminals 18 and 20 can be changed.

On the other hand, the signal propagated to the left side of the delay line also reaches the casing 5 after a delay time multiplied by the number of sections on the left side from the input point.
It is consumed by the resistance Ro within.

In this case, in the case of double-contact operation, the inductance L adjacent to the short-circuited inductance L has only one side of mutual induction, so the value of each inductance L as a delay line element is L(1
+a).

Usually, the coupling coefficient a between inductance L is 0.15
The delay time and characteristic impedance Ro in this section are approximately 7% lower than in equation (2) above, but are not related to the delay time variable function at all.

In a single contact, the inductance L is not short-circuited by the movable contact 26, and the adjacent left and right inductances L are coupled with a coupling coefficient of -a, and each is further coupled with the neighboring inductance L with a coupling coefficient of +a. Therefore, the value of each inductance is L(1+a-a)=L, and the value is lower than that in the case of multiple contact described above.

Therefore, in the case of single contact, the capacitance of the capacitor at the single contact point is reduced to 1/2 and the inductance is reduced to 1/(1+a) compared to double contact, so the delay time is approximately 0.3 td shorter than in double contact.

In the variable delay line shown in Fig. 1,
The delay time is the smallest when the movable contact 26 is moved to the right, and this point serves as the reference point for the variable range of the delay time. When the movable contact 26 is sequentially moved to the left from this point, the movable contact 26 alternately repeats double contact and single contact, and the delay time of the signal obtained at the output terminals 18 and 20 is 0.3td, td with respect to the reference point. , 1.3td,
Changes to 2td, 2.3td...

As a result, it becomes possible to realize more detailed stepwise changes in delay time, td, 2td, etc., obtained by repeating single contacts.

The inventor proposed a non-magnetic bobbin 1 having a rectangular cross section with a width of 3 mm, a thickness of 0.4 mm, and a length of 16 mm, and a polyurethane-coated copper wire with a diameter of 0.07 mm.The number of turns in one section is 9 turns, and the number of turns in the adjacent section is The pitch is 0.7mm, total
An inductance element 3 with 20 sections is formed, and the capacitance C of each section is 10 pF, and the coupling coefficient a is 0.15.
We selected and conducted an experiment.

As a result, the delay time td per section is calculated at 1nS.
A variable delay line containing a delay line with a characteristic impedance Ro of 20nS and 100Ω is obtained.In the single contact position, the delay line is 1nS, 2nS...20nS, and in the double contact position, approximately
0.3nS, 1.3nS, 2.3nS...19.3nS were obtained.

In the above-described embodiment, the lead wire 2a from the connection point of the coil 2 was positioned by the V-shaped notch 10, but the present invention is not limited to this, and for example, a plurality of small protrusions in series can be used. In short, the object of the present invention can be achieved by forming an uneven portion for positioning the lead wire. It is sufficient to form it at the end of the terminal board 6.

Coil 2 in the above-mentioned inductance element 3
Although the conductive wire is wound into a single-layer solenoid shape, it is also possible to use a spiral winding or a multilayer winding, and the bobbin is not essential. Also,
For example, a delay line unit in which a wire is wound around a ferrite drum core, a tap is pulled out from the middle of the winding, and a capacitor is connected can also be implemented as an inductive m-type delay line in which a plurality of delay lines are connected in cascade.

Furthermore, the movable contact means may be of any type as long as it slides by alternately repeating single contact with each fixed contact and double contact with adjacent fixed contacts.

As explained above, in the present invention, the lead wire connecting the connection point of adjacent coils and the fixed contact is positioned by the uneven part provided at the end of the terminal board, so the shape of the variable delay line is Even if it is made smaller, the lead wires are easier to handle and short circuits between fixed contacts are less likely to occur.

Therefore, productivity and quality can be improved and costs can be kept low.

[Brief explanation of the drawing]

1 and 2 are front sectional views and side sectional views showing one embodiment of the present invention, FIG. 3 is an equivalent circuit diagram of the variable delay line shown in FIG. 1, and FIG. 4 is the same as shown in FIG. 1. FIG. 3 is a partial perspective view showing the vicinity of a fixed contact array. 1...Non-magnetic bobbin, 2...Coil, 2a...
...Lead wire, 3...Inductance element, 5...
Housing, 6... Terminal board, 8... Fixed contact, 9... Fixed contact row, 10... Uneven part (V-shaped notch),
21... Conductive plate, 24... Spring holder, 25...
Movable contact means (sliding spring), 26... Movable contact means (movable contact).

Claims (1)

[Claims for Utility Model Registration] (1) A plurality of coils made of wound conductors are connected in series at a predetermined pitch, and a plurality of fixed contacts constituting a fixed contact row formed on a terminal board are connected to adjacent ones of the coils. Connect the coil connection points with lead wires,
Connect a capacitor between the connection point and ground,
Arranging a movable contact means that moves by alternately repeating single contact with each of the fixed contacts and double contact with adjacent fixed contacts, and positioning the lead wire at the end of the terminal plate. A variable delay line characterized by forming uneven parts. (2) The variable delay line according to claim 1, wherein the uneven portion is a V-shaped notch.