CN103247492A - Electromagnet back-up protection device of low-voltage circuit breaker - Google Patents

Abstract

The invention discloses an electromagnet backup protection device for a low-voltage circuit breaker. The device includes a support member fixed in the circuit breaker, a linkage draw bar that is movably connected to the support member and can rotate along a movable connection shaft, and is fixed on the The yoke iron on the main circuit wire row of the circuit breaker body and located under the linkage drawbar, one end is fixed on the support and the other end is fixed on the compression spring on the linkage drawbar. The position of the iron corresponds to the armature. The device is small in size and compact in fit, and can be directly installed on the circuit breaker body. The device directly drives the drawbar to rotate, thereby pushing the plastic lock to release, which greatly shortens the time required for the short-circuit action and improves the safety performance of the circuit breaker. short circuit protection capability. Especially for small-capacity electronic circuit breakers, the use of this device will make the protection function of the circuit breaker more comprehensive.

Description

An electromagnet backup protection device for a low-voltage circuit breaker

technical field

The invention relates to an electromagnet backup protection device for a low-voltage circuit breaker, which belongs to the field of low-voltage electrical appliances.

Background technique

Low-voltage circuit breakers, as protective appliances for low-voltage power distribution systems, can not only switch on and off circuits under load, but also automatically trip under short-circuit, overload and low voltage (loss of voltage). Molded case circuit breakers in the prior art often do not have an electromagnet backup protection device due to their small size. In addition, a secondary mechanism is usually used to trigger the tripping of the circuit breaker, and there are many triggering links, resulting in a long time for triggering; The circuit breaker of the trip unit needs to go through the main circuit current detection, amplification, and then send a signal to the electronic trip unit to trigger the tripping action of the circuit breaker. If a fault occurs, the circuit cannot be broken normally, and the protected equipment and switching appliances will be subjected to huge thermal shock and electromotive force, and the consequences will be very serious.

Contents of the invention

Aiming at the above-mentioned defects of low-voltage circuit breakers in the prior art, the present invention provides an electromagnet backup protection device for low-voltage circuit breakers.

Technical scheme of the present invention is:

An electromagnet backup protection device for a low-voltage circuit breaker, including a support fixed in the circuit breaker, a linkage drawbar that is movably connected to the support and can rotate along a movable connection shaft, and fixed to the main circuit of the circuit breaker body The yoke on the wire row and below the linkage drawbar, one end is fixed on the support, and the other end is fixed on the compression spring on the linkage drawbar, which is set on the bottom surface of the linkage drawbar, and its position corresponds to the position of the yoke armature.

As a further improvement of the present invention, the yoke is provided with a fixing hole, and the yoke is fixedly connected to the main circuit conductor bar of the circuit breaker body through the fixing hole and screws.

As a further improvement of the present invention, a cylindrical first boss is provided on one side of the support, a cylindrical first groove is also provided on the support, and the support passes through the first boss and the first recess. The slot achieves its fixation between the two bases of the circuit breaker.

As a further improvement of the present invention, a bayonet is provided on the support, and a cylindrical connecting shaft is provided on the side of the linkage drawbar corresponding to the bayonet, and the connecting shaft is clamped in the bayonet of the support, so that The linked drawbar can only perform rotational movement about the connecting axis.

As a further improvement of the present invention, a second groove is provided at the bottom of the linkage drawbar, and the armature is arranged in the second groove at the bottom of the linkage drawbar.

As a further improvement of the present invention, the linkage drawbar is provided with a conical second boss, the support is provided with a conical third boss corresponding to the position of the second boss, and one end of the compression spring It is fixed on the third conical boss on the support, and the other end is fixed on the second conical boss on the linkage drawbar.

The beneficial effects of the present invention are:

The electromagnet backup protection device of the low-voltage circuit breaker of the present invention is small in size and compact in fit, and can be directly installed on the circuit breaker body. The time required for short-circuit operation improves the ability of short-circuit protection. Especially for small-capacity electronic circuit breakers, the use of this device will make the protection function of the circuit breaker more comprehensive.

Description of drawings

Fig. 1 is the structural diagram of the electromagnet backup protection device of a kind of low-voltage circuit breaker of the present invention;

Fig. 2 is the installation schematic diagram of the electromagnet backup protection device of a kind of low-voltage circuit breaker of the present invention;

Fig. 3 is the structural diagram of yoke iron among the present invention;

Fig. 4 is a structural diagram near the half of the outer surface of the support in the present invention;

Fig. 5 is a structural diagram near the half of the inner surface of the support in the present invention;

Fig. 6 is the structural diagram of linkage drawbar among the present invention;

Fig. 7 is a structural diagram of an armature in the present invention;

Fig. 8 is a working state diagram of the electromagnet backup protection device when there is no short-circuit current in the circuit breaker;

Fig. 9 is a working state diagram of the electromagnet backup protection device when there is a short-circuit current in the circuit breaker.

In the figure: 1. Support piece; 2. Linkage draw bar; 3. First groove; 4. Compression spring; 5. Armature; 6. Fixing hole; 7. Bayonet; 8. Connecting shaft; 10, the third boss; 11, the second groove; 12, the first boss; 13, the yoke; 14, the main circuit wire row; 15, the lock.

Detailed ways

The present invention will be described in further detail below in conjunction with the accompanying drawings.

The structure of a kind of electromagnet backup protection device of the present invention is as shown in Figure 1, comprises:

The yoke 13 has a fixing hole 6 and is fixedly connected to the main circuit conductor bar 14 of the circuit breaker body by screws. (Refer to Figure 3)

The support member 1 is used to support the linkage drawbar 2, and has a cylindrical first boss 12 on one side, and a cylindrical first groove 3 on both sides, through the first boss 12 and the first groove 3 to Realize the fixation of itself between the two bases of the circuit breaker (refer to Figure 2). The upper end of the support member 1 has a conical third boss 10 and a bayonet 7 . (Refer to Figure 4 and Figure 5)

The linkage drawbar 2, the cylindrical connecting shaft 8 on the linkage drawbar 2 is stuck in the bayonet 7 of the support member 1, so that the linkage drawbar 2 can only perform rotational movement. There are two conical second bosses 9 on the linkage drawbar 2 . (Refer to Figure 6)

Compression spring 4, one end of compression spring 4 is fixed on the conical third boss 10 on the support member 1, and the other end is fixed on the conical second boss 9 on the linkage drawbar 2.

The armature 5 is arranged in the second groove 11 at the bottom of the linkage drawbar 2 . (Refer to Figure 7)

The support 1 is fixed by cooperating with the boss and groove on the circuit breaker, the connecting shaft 8 on the linkage drawbar 2 is stuck on the bayonet 7 of the support 1, and the two ends of the compression spring 4 are respectively fixed on the support 1 and On the conical boss of the linkage drawbar 2, the compression spring 4 applies a spring force to the linkage drawbar 2 to cause the linkage drawbar 2 to rotate away from the yoke 13, and the linkage drawbar 2 is prevented by the limit of the electronic release. Continue to rotate. At this time, the linkage drawbar 2 forms a certain acute angle with the horizontal plane. This angle is the starting angle of the linkage drawbar 2. The corresponding state is the working state of the electromagnet backup protection device when there is no short-circuit current in the circuit breaker. This state As shown in Figure 8.

When a short-circuit fault occurs, a short-circuit current greater than the set value flows in the electromagnet backup protection device, and the yoke 13 and the armature 5 are magnetized to become two magnets with opposite polarities, and the electromagnetic force between them is greater than that of the compression spring 4 spring force, the two attract. The suction of the yoke 13 and the armature 5 drives the linkage drawbar 2 to rotate in the direction close to the yoke 5 until the yoke 13 contacts the armature 5, and then pushes the plastic lock 15 on the circuit breaker to trip the circuit breaker, thereby cutting off Circuit, the state is shown in Figure 9. When the current of the main circuit is less than a certain value or the power supply is interrupted, the electromagnetic attraction force is less than the spring force of the compression spring 4, and the linkage draw bar 2 will return to the original release position under the action of the spring.

The armature 5 and the yoke 13 in the magnetic back-up protection device provided by the present invention can be magnetized into magnets with opposite polarities by the current in the same direction, and generate an electromagnetic force sufficient to overcome the spring force of the compression spring under a small current. The yoke 13 and the armature 5, the armature 5 directly drives the linkage drawbar 2 to push the lock 15 to make the circuit breaker trip.

The electromagnet backup protection device provided by the present invention is small in size and compact in fit, and can be directly installed on the circuit breaker body. The device directly drives the drawbar to rotate, thereby pushing the plastic lock to release, which greatly shortens the short-circuit action The required time improves the ability of short-circuit protection, especially for small-capacity electronic circuit breakers, the use of this device will make the protection function of the circuit breaker more comprehensive.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (6)

1. the electric magnet backup protection apparatus of a low-voltage circuit breaker; it is characterized in that: comprise the strutting piece (1) that is fixed in the circuit breaker; be movably connected on the strutting piece; can be along the interlock draw bar (2) that flexibly connects axis rotation; be fixed on the major loop lead row of breaker body; be positioned at the yoke (13) of interlock draw bar (2) below; one end is fixed on the strutting piece (1); the other end is fixed on the stage clip (4) on the interlock draw bar (2), is arranged on interlock draw bar (2) bottom surface; the armature (5) that its position is corresponding with the position of yoke (13).

2. the electric magnet backup protection apparatus of low-voltage circuit breaker as claimed in claim 1; it is characterized in that: described yoke (13) is provided with fixing hole (6), and yoke (13) is fixedly attached to the major loop lead row of breaker body by fixing hole (6) and screw.

3. the electric magnet backup protection apparatus of low-voltage circuit breaker as claimed in claim 1; it is characterized in that: a side of described strutting piece (1) is provided with columniform first boss (12); also be provided with columniform first groove (3) on the strutting piece (1), strutting piece (1) is realized from fixing between two bases of circuit breaker by first boss (12) and first groove (3).

4. the electric magnet backup protection apparatus of low-voltage circuit breaker as claimed in claim 1; it is characterized in that: described strutting piece (1) is provided with bayonet socket (7); the position corresponding with bayonet socket (7) is provided with cylindrical connecting axle (8) on interlock draw bar (2) side; connecting axle (8) is arranged in the bayonet socket (7) of strutting piece (1), makes interlock draw bar (2) be rotated motion around connecting axle (8).

5. the electric magnet backup protection apparatus of low-voltage circuit breaker as claimed in claim 1 is characterized in that: interlock draw bar (2) bottom is provided with second groove (11), and described armature (5) is arranged in second groove (11) of interlock draw bar (2) bottom.

6. as the electric magnet backup protection apparatus of any described low-voltage circuit breaker in the claim 1 to 5; it is characterized in that: described interlock draw bar (2) is provided with conical second boss (9); strutting piece (1) is provided with position conical three boss (10) corresponding with second boss (9) position; one end of stage clip (4) is fixed on taper shape the 3rd boss (10) on the strutting piece (1), and the other end is fixed on taper shape second boss (9) on the interlock draw bar (2).

Images