JPS6213394Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a communication protector used at a line lead-in point for telephones and other wired communication household equipment.

A communication protector is installed at the indoor lead-in point of the track.
To protect in-house equipment and protect operators from danger when communication lines come into contact with power lines or when surges arrive on the lines due to lightning. In recent years, semiconductor integrated circuits have come to be used in household equipment, and there has been a demand for higher performance communication protectors.

In response to this demand, excellent communication protector circuits have been proposed. An example of a conventional circuit is shown in FIG.
Line terminals L ₁ and L ₂ are connected to contact breakers TB ₁ and TB ₂ , respectively.
It is connected to the home equipment terminals T ₁ and T ₂ via. M ₁ and M ₂ are the drive windings of the contact circuit breaker. Fuses F ₁ and F ₂ are connected in parallel with the normally closed contacts K ₁ and K ₂ of the contact breakers TB ₁ and TB ₂ , respectively. There are 2 wires between the home equipment terminals T ₁ and T ₂ and the ground.
Polar discharge tubes A ₁ and A ₂ are connected. Furthermore, diode discharge tubes A ₃ and A ₄ are connected in parallel to the drive windings M ₁ and M ₂ , respectively.

In devices with this kind of circuit configuration, the contacts are always connected.
Since K ₁ and K ₂ are closed, most of the communication current flows through the contacts K ₁ and K ₂ , and only a small proportion is shunted to the fuses F ₁ and F ₂ . When a lightning surge arrives at the line terminals L ₁ and L ₂ in this condition, the diode discharge tube
A ₁ and A ₂ are short-circuited. Therefore, the home equipment terminals T ₁ and T ₂ have the same potential (ground potential), and the home equipment is protected. Generally, the duration of a lightning surge is short, so the contact breakers TB ₁ and TB ₂ do not operate. Therefore, when the lightning surge ends, the diode discharge tube
The discharge of A ₁ and A ₂ also ends, and the circuit returns to its normal state.

When the line terminals L ₁ and L ₂ come into contact with the power line and a high voltage alternating current arrives, current flows through the drive windings M ₁ and M ₂ following the discharge of the diode discharge tubes A ₁ and A ₂ .
Contact breakers TB ₁ and TB ₂ operate and contacts K ₁ and K ₂ open. This allows current to flow through the fuses F ₁ and F ₂ , and if the abnormally high voltage continues, the fuses F ₁ and F ₂ will melt.

When fuses F ₁ and F ₂ blow, the circuit becomes open and the household equipment is protected.

Furthermore, when a lightning surge with a sharp voltage rise occurs due to the operation of the diode discharge tubes A ₃ and A ₄ , it is possible to prevent the contact breaker from operating. In other words, since the impedance of the drive windings M ₁ and M ₂ is quite low, a voltage higher than the operating voltage may be present at both ends of the bipolar discharge tubes A ₃ and A ₄ due to contact with power lines or normal lightning surges. does not occur. but,
A lightning surge with a sharp voltage rise arrives, and the drive winding
Even if the voltage across M ₁ and M ₂ is instantaneous, the voltage across the diode discharge tube A ₃ ,
Higher than the operating voltage of A ₄ , the contact breaker TB ₁ ,
Before the operation of TB ₂ , the drive windings M ₁ and M ₂ are short-circuited by the discharge of the diode discharge tubes A ₃ and A ₄ , and the contact breaker
The operation of TB ₁ and TB ₂ is prevented.

Therefore, in the event of a lightning surge, the fuses F ₁ and F ₂ do not blow out, and the number of times the fuses need to be replaced or maintained can be reduced. In addition, even if the fuse blows due to cross-contact, etc., once the cause of the abnormally high voltage is removed, the subscriber can manually restore the contacts K ₁ and K ₂ of the contact breakers TB ₁ and TB ₂ . Communication can be restored for the time being. Therefore, there is no need for urgent dispatch of maintenance personnel from the telephone office, and the number of maintenance personnel can be significantly reduced.

Furthermore, since the fuses F ₁ and F ₂ are inserted in parallel to the contacts K ₁ and K ₂ , there is almost no spark when the contacts K ₁ and K ₂ are opened. Fuses F ₁ and F ₂ are contacts K ₁ and K ₂
It will melt after opening sufficiently. Therefore, the contact breakers TB ₁ and TB ₂ can be made smaller and less expensive.

Furthermore, contact breakers TB ₁ and TB ₂ do not operate when a lightning surge with a sharp voltage rise occurs.
Contacts K ₁ and K ₂ open due to lightning surges, and the device cannot be used for a long time without noticing this.

In this way, the conventional circuit is excellent, but
It requires a large number of diode discharge tubes, which complicates the circuit configuration.
This method has drawbacks such as increased cost, and when a deviation occurs at the start of operation of the discharge tube, lateral voltage is generated and there is a risk of damaging household equipment.

The present invention is intended to improve these points, and aims to provide a communication protector that does not have a complicated circuit configuration, is inexpensive, and does not generate lateral voltage.

The present invention consists of fuses F ₁ , _{F 2 whose} one ends are connected to line terminals L _{1 ,} L ₂ , contacts K ₁ ,
K ₂ and a pentode discharge tube A in which the other ends of the fuses F ₁ and F ₂ are respectively connected to the outermost electrode and the innermost electrode is grounded.
A drive coil of the contact breaker is connected between the other ends of F ₁ and F ₂ and each intermediate electrode of the pentode discharge tube.
M ₁ and M ₂ are connected, and the potential points of the intermediate electrodes are connected to the home equipment terminals T ₁ and T ₂ , respectively.

An embodiment of the present invention will be described based on the drawings.
FIG. 2 is a diagram showing the main circuit configuration of an embodiment of the present invention. Contact breakers TB ₁ and TB ₂ are connected to the line terminals L ₁ and L ₂ , respectively. This contact breaker TB ₁ ,
TB ₂ are respectively connected to the middle electrodes of the pentode discharge tube A. In-house equipment terminals T ₁ and T ₂ are connected to the middle electrode of this pentode discharge tube A, respectively. The outermost electrode of this pentode discharge tube A is connected to the contacts K ₁ and K ₂ of the contact breakers TB ₁ and TB ₂ and the drive winding M ₁ ,
M ₂ and are respectively connected to the intermediate potential point. The innermost electrode of this pentode discharge tube A is grounded. Furthermore, fuses F ₁ and F ₂ are connected in parallel to the contacts K ₁ and K ₂ , respectively.

The characteristic operation of the present invention will be explained using such a circuit configuration.

When a lightning surge arrives at the line terminal L ₁ or L ₂ , a discharge starts between the grounded electrode of the pentode discharge tube A and an intermediate electrode with a short electrode spacing. . This discharge immediately propagates throughout the pentode discharge tube A. This allows the line terminal
L ₁ and L ₂ are shorted. For this reason, the home equipment terminal
T ₁ and T ₂ are also at the same potential (ground potential), protecting household equipment and users from lightning surges. Generally, lightning surges have a short duration, so contact breakers are
TB ₁ and TB ₂ do not operate, and when the lightning surge ends, the discharge ends and the circuit returns to its original state.

Furthermore, when a lightning surge with an extremely sharp voltage rise occurs, the entire pentode discharge tube A is discharged and short-circuited, so the drive windings M ₁ and M ₂ have impedance against the lightning surge with a sharp rise. More current flows through the outermost electrode of the pentode discharge tube A and is shorted to ground than through the outermost electrode of the pentode discharge tube A. Therefore, even if a lightning surge with an extremely sharp voltage rise occurs, the contact breakers TB ₁ and TB ₂ will not operate. Therefore, even though contact breakers TB ₁ and TB ₂ were activated due to a lightning surge, the contacts were disconnected.
K ₁ and K ₂ are never left open and used.

In addition, power line contact may occur in the communication cable, and abnormally high voltage alternating current is transmitted to line terminal L ₁ or L ₂ (e.g.
L ₁ ), a discharge is started between the ground electrode and the intermediate electrode of the pentode discharge tube A, and this discharge propagates throughout the tube. This discharge causes the line terminal to
L ₁ and L ₂ are short-circuited, and the home equipment terminals T ₁ and T ₂ have the same potential (ground potential), thereby protecting the home equipment and the user from abnormally high voltage.

If this abnormally high voltage continues, the current flowing through the pentode discharge tube A to the ground will be divided into the outermost electrode and the middle electrode, and the drive windings M ₁ and M ₂ will be divided into the outermost electrode and the middle electrode.
(for example, M ₁ ), the contact breaker
TB ₁ , TB ₂ (e.g. TB ₁ ) operate, contacts K ₁ , K ₂
(e.g. K ₁ ) is opened. At this time fuse F ₁ ,
There is no spark as F ₂ are connected in parallel. If the abnormally high voltage continues in this state, fuses F ₁ and F ₂ (for example, F ₁ ) will melt. Hughes F ₁ ,
When F ₂ blows, the circuit is opened, protecting the equipment and the user.

After this, if the cause of the abnormal high voltage is removed, the subscriber can manually disconnect the contacts of contact breakers TB ₁ and TB ₂ .
K ₁ and K ₂ are restored and communication is restored. For this reason,
There is no need for emergency fuse replacement maintenance from the telephone office.

As explained above, the present invention has the following advantages: (1) Since the pentode discharge tube is used, the circuit configuration is not complicated and the cost can be reduced. (2) In cases such as lightning surges, The fuse does not blow out, and the number of times the fuse needs to be replaced and maintained can be reduced.

(3) Even if a fuse blows due to power line cross-contact, etc., the contact of the contact breaker can be restored by manual operation by the subscriber, and communications can be restored; (4) Since the fuses are inserted in parallel with the contacts of the contact circuit breaker, there is almost no spark when the contacts are opened, and the number of maintenance personnel at the telephone office can be significantly reduced. (5) In the event of a lightning surge with an extremely sharp rise in voltage, the contact breaker will not operate and the contact will break. It has excellent effects such as preventing the circuit breaker from being used unnoticed even though it has been opened by a lightning surge.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the main circuit configuration of a conventional example. FIG. 2 is a diagram showing the main circuit configuration of an embodiment of the present invention. L ₁ , L ₂ ... line terminal, T ₁ , T ₂ ... home equipment terminal, F ₁ , F ₂ ... fuse, TB ₁ , TB ₂ ... contact breaker, M ₁ , M ₂ ... drive winding Line, K ₁ , K ₂ ... contact,
A...5-pole discharge tube, _A1 to _A4 ...2-pole discharge tube.

Claims (1)

[Scope of utility model registration request] Fuse with one end connected to line terminals L ₁ and L ₂
F ₁ , F ₂ , contacts K ₁ , K ₂ of the contact circuit breaker connected in parallel with these fuses F ₁ , F ₂ , and the other ends of each of the fuses F ₁ , F ₂ are the outermost electrodes, respectively. and a pentode discharge tube A connected to the pentode discharge tube A whose innermost electrode is grounded, and the contact breaking point is provided between each other end of the fuses F ₁ and F ₂ and each intermediate electrode of the pentode discharge tube. 1. A communication protector characterized in that drive windings M ₁ and M ₂ of the device are connected, and the potential points of the intermediate electrodes are connected to in-home equipment terminals T ₁ and T ₂ , respectively.