RU2795958C1 - Circuit breaker with adjustable thermal and electromagnetic current disconnectors - Google Patents

Abstract

FIELD: electric power and electrical engineering.

SUBSTANCE: invention relates to circuit breakers designed to protect electrical circuits from overload currents and short circuits. The invention relates to circuit breakers designed to protect electrical circuits from overload currents and short circuits. The electromagnetic disconnector regulator is configured to rotate around its axis, has a curved surface, the shape of which is determined by the dependence of the force of the return spring on its extension, and when rotated by a ledge, it unfolds the adjustment rail of the electromagnetic disconnector, thereby changing the tension of the tenfold current setpoint adjusting spring. In the position of the electromagnetic disconnector regulator for a five-fold current setpoint, the armature of the electromagnetic disconnector, when triggered, overcomes only the force of the five-fold setpoint adjustment spring, while the ten-fold setpoint adjustment spring is not deformed and does not generate force. In the ten-fold setpoint regulator position, the electromagnetic disconnector armature overcomes the calibrated force of the ten-fold setpoint adjustment spring and the five-fold setpoint adjustment spring. While being attracted to the magnetic circuit, the armature unfolds the release rail, which leads to the tripping of the automatic circuit breaker. The thermal disconnector regulator is configured to rotate around its axis, during rotation, the thermal disconnector adjusting rail moves linearly along the rotation axis of the main circuit breaker rail, thereby changing the gap between the adjusting screw and the complex-shape projections of the thermal disconnector adjusting rail.

EFFECT: providing adjustment of the setpoint of the thermal disconnector and the electromagnetic disconnector of the circuit breaker and providing, at the manufacturing stage of the circuit breaker, calibration of the specified trip current for each pole for a fivefold and tenfold current setpoint, whereas calibrating the pre-set trip current for a tenfold setpoint does not affect the specified trip current for a fivefold setpoint.

1 cl, 4 dwg

Description

FIELD OF TECHNOLOGY

The invention relates to the field of electric power and electrical engineering, in particular to circuit breakers designed to protect electrical circuits from overload currents and short circuits.

BACKGROUND OF THE INVENTION

To date, the closest solution in terms of technical essence is known from the prior art - a device for thermoelectromagnetic protection of an automatic circuit breaker, used in circuit breakers and providing for the possibility of adjusting and turning off the circuit breaker in the event of overload currents (abnormal currents) and short circuit currents, (https://www1 .fips.ru/, FIPS open register of useful models, utility model patent No. RU197945)

In the known circuit breaker, the holder with which the armature springs of the electromagnetic release are connected is made as a single piece without additional embedded parts. In each electromagnetic release switch pole, only one armature spring is installed, which creates a force corresponding to five and ten times the setting.

The disadvantages of this device are:

- increased requirements for the accuracy of manufacturing parts of the thermomagnetic protection device due to the use of one armature spring for all adjustable settings of the electromagnetic release;

- the absence of a calibration body for the set operating current for each pole at the stage of manufacture of the circuit breaker.

DISCLOSURE AND IMPLEMENTATION OF THE INVENTION

The claimed design of the technical solution consists of:

- case of the circuit breaker (4), containing electromagnetic and thermal releases for each of the poles of the circuit breaker, common for three poles of the adjustment rail of the thermal release (1), common for three poles of the rail of the adjustment electromagnetic release (2), common for three poles of the trip rail (3);

In the housing (4), for each of the circuit breaker poles are installed:

- electromagnetic release (hereinafter - EMR, Figures 1,2) consisting of racks (5) installed in the grooves of the housing (4), an adjusting EMR rail (2), common for three poles, installed in the racks (5) with the possibility of rotation around its axis, the regulator (6), installed in a special way in the cover of the automatic switch with the protrusion of the regulator (7) (Figure 3); adjusting springs with a tenfold current setting (8), coupled with hooks (9) to plates (10) of the adjusting EMR rail (2) and hooks (11), anchors (12) installed in plates with clamps (15), leads (13 ), magnetic circuits (14), adjusting springs with a fivefold current setting (16) installed between the armatures (12) and screws (17);

- thermal release (Figure 4, hereinafter referred to as TP), consisting of an adjustment rail with complex-shaped protrusions (1), mounted on the release rail (3) with the possibility of rotation together with the trip rail (3), the TP regulator (18), terminals ( 13), thermoelements (19) fixed on the output (13), adjusting screws (20).

The essence of the proposed technical solution lies in the fact that the EMR regulator is installed with the possibility of rotation around its axis, during rotation, the regulator turns the EMR control rail with a ledge, thereby changing the tension of the control spring by a tenfold setting. The regulator has a curved surface, the shape of which is determined by the dependence of the force of the return spring on its extension. In the position of the EMR regulator for five times the setting, the EMR armature, when actuated, overcomes only the force of the five times set adjustment spring, the ten times set adjustment spring is not stretched and therefore does not generate force. In the 10x setpoint adjuster position, the EMR armature overcomes the calibrated force of the 10x setpoint adjusting spring and the 5x setpoint adjusting spring. Attracted to the magnetic circuit, the armature unfolds the trip rail, which leads to the tripping of the automatic circuit breaker.

Calibration of the tenfold setting is carried out by bending embedded parts in the form of metal plates, which increases or decreases the tension of the tenfold adjustment spring, increasing or decreasing the force that the EMR armature must overcome when triggered. In addition, by bending embedded parts in the form of metal plates, the influence of backlashes that reduces the reliability of the EMR operation is eliminated. Calibration of the five-fold setpoint is carried out by turning the adjusting screw, which increases or decreases the compression of the five-fold setpoint spring.

The TP regulator is installed with the possibility of rotation around its axis, during rotation, the TP adjustment rail moves linearly along the axis of rotation of the circuit breaker trip rail, thereby changing the gap between the adjusting screw and the complex-shaped protrusions of the TP adjustment rail. The gap is determined by the dependence of the deflection of the thermoelement on the current, the thermoelement, when TP is triggered, by bending, ensures the action of the adjusting screw on the adjusting rail, which leads to the tripping of the circuit breaker.

Thus, due to the appropriate calibration and adjustment elements, it is possible to adjust both overload protection and protection against short-circuit currents of the automatic circuit breaker, while adjusting the protection against short-circuit currents does not change the time limits for the operation of protection against overloads.

The technical result of the proposed technical solution is to provide adjustment of the TP and EMR settings of the circuit breaker by the consumer, providing at the stage of manufacture of the circuit breaker calibration of the specified trip current for each pole for a five-fold and ten-fold setting, while calibrating the preset trip current for a ten-fold setting does not affect the specified current operation for five times the setpoint. It becomes possible to exclude the influence of backlashes, which reduces the reliability of the EMR operation, allowing the use of a design with much larger tolerances for the manufacture of parts. When adjusting the protection against short-circuit currents, the time limits for the operation of the protection against overloads do not change.

The technical result of the proposed technical solution is achieved due to the following:

- installation in the body of the circuit breaker (4) of an electromagnetic and thermal release for each of the poles of the circuit breaker, common for three poles of the adjustment rail of the thermal release (1), common for three poles of the rail of the adjustment electromagnetic release (2), common for three poles of the trip rail (3);

Installations in the housing (4), for each of the poles of the circuit breaker:

- an electromagnetic release (Figures 1, 2) consisting of racks (5) installed in the grooves of the housing (4), an adjusting EMR rail (2) installed in the racks (5) with the possibility of rotation around its axis, a regulator (6), a special way installed in the cover of the automatic switch with the protrusion of the regulator (7) (Figure 3); adjusting springs with a tenfold current setting (8), coupled with hooks (9) to plates (10) of the adjusting EMR rail (2) and hooks (11), anchors (12) installed in plates with clamps (15), leads (13 ), magnetic circuits (14), adjusting springs with a fivefold current setting (16), installed between the armatures (12) and screws (17);

- thermal release (Figure 4), consisting of an adjusting rail with projections of complex shape (1), mounted on the release rail (3) with the possibility of rotation together with the trip rail (3), TP regulator (18), terminals (13), thermocouples (19) fixed on the terminal (13), adjusting screws (20).

The proposed technical solution works as follows;

When an electric current passes through the terminal (13), energy is released in the form of heat, the thermoelement (19) heats up and bends to the side with a lower thermal expansion coefficient. When the set current value is exceeded, the bending of the thermoelement (19) reaches a value sufficient for the screw (20) of the thermoelement (19) to interact with the adjusting rail TP (1) and turn it together with the release rail (3), which leads to to trip the circuit breaker.

To adjust the setting of the operating current, it is necessary to turn the regulator of the thermal release (18). Under its action, the protrusion (21) of the TP regulator (18) interacts with the adjusting rail TP (1), the linear movement of the adjusting rail TP (1) occurs along the axis of rotation of the release rail (3), which leads to a decrease or increase in the gap between the screw (20 ) and the intricate projections of the TP adjusting rail (1). With different clearances, TP trips at different overload currents.

When an electric current passes through the output (13), a magnetomotive force is created, which ensures the conduction of a magnetic flux through the working gap between the armature (12) and the magnetic circuit (14). When the set current value is exceeded, the armature (12) is attracted to the magnetic circuit (14), overcoming the force of the spring (16) at a fivefold setting and of the springs (8), (16) at a tenfold setting. Under the influence of the armature (12), the trip rail (3) turns around, which leads to the tripping of the circuit breaker.

To adjust the short-circuit protection setting, turn the EMR regulator (6). Under its action, the protrusion (7) interacts with the protrusion (22) of the adjusting EMR rail (2), the adjusting EMR rail (2) turns around its axis, which leads to a decrease or increase in the tension of the adjusting spring tenfold setting (8). At different values of the spring tension, the electromagnetic protection unit operates at different values of the short circuit currents.

At the stage of manufacturing the circuit breaker, the set trip current of the tenfold setting for each pole is calibrated by bending the embedded parts in the form of metal plates (10), which increases or decreases the tension of the tenfold setting adjusting spring (8). In turn, this increases or decreases the force that the armature (12) must overcome when triggered. Calibration of the set operating current for a five-fold setting is carried out by turning the screw (17), which increases or decreases the compression of the five-fold adjustment spring (16).

Claims (1)

Automatic circuit breaker with adjustable thermal and electromagnetic current releases, containing a housing with placed adjustable electromagnetic current release and thermal current release installed for each of the poles of the circuit breaker, characterized in that the electromagnetic current release contains adjusting springs of tenfold and fivefold settings common to all poles an adjusting rail installed in racks with the possibility of rotation around its axis, with embedded parts in the form of metal plates, an electromagnetic release regulator with a protrusion in the form of a curved surface, which, when turned in the position for a tenfold setting, unfolds the adjusting rail, which provides a tension of the adjusting spring tenfold settings, and in the position for a fivefold setting, the necessary play is structurally provided between the hooks of the adjusting springs and embedded parts in the form of metal plates.

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