SU1343461A1 - Current-limiting device for automatic switches - Google Patents

Abstract

The invention relates to electrical engineering, in particular to automatic switches with electrodynamic current-limiting devices. The aim of the invention is to reduce the consumption of materials and increase the reliability of the contacts. The movable contacts 2 are located at opposite ends of their common contact holder 6 on opposite sides with respect to a plane passing through the longitudinal axis of the contact holder 6. The longitudinal axes of said contact holders 6 of all poles are located in one plane and parallel to each other. The contact holder 6 has, along the length between the anchorage points of the movable contacts 2, a guide pin 8, which enters the grooves 9 of the insulating body 1, which limit the ability of the contact holder 6 to move in all directions in a plane perpendicular to the longitudinal plane of the longitudinal 05

Description

the axes of the contact holder 6 movable contacts 2, all poles, but makes it impossible for the contact holder 6 to rotate relative to the line of contact of one or the other pair of movable 2 and fixed 3 contacts in the plane of the longitudinal axes of the contact holder 6 when a short-circuit current occurs between contact1.

The invention relates to low-voltage electrical apparatus, in particular, electrodynamic current-limiting devices that are connected in series with automatic switches (AB) in order to increase their limiting switching capacity (PCB).

The aim of the invention is to increase the reliability of the contacts and reduce the consumption of materials.

The drawing shows the proposed device.

Its device has an insulating body 1 and in each pole there are two movable 2 and fixed 3 contacts, arcing horns 4 and arcing chambers 5, contact holders 6 movable contacts 2 in each pole parallel to each other, contact springs 7, pins 8, fixed in the co-holders 6 of the two podgaknyh contacts and included in the grooves 9 of the insulating body 1 or racks fixed in the insulating body 1.

In the absence of short-circuit current, both pairs (movable 2 and fixed 3) contacts in each pole are closed and pressed to each other by contact springs 7. Pins 8 entering the grooves 9 of the insulating body 1 fix the position of the contacts in all directions in the plane of their contact.

In the event of a short circuit, the operation of the current limiting device is as follows.

Depending on the phase of the voltage at which a short circuit occurs, the distribution of currents between the directional holders 6 of the movable contacts 2 creates electrodynamic forces that cause junk from the movable contacts 2, while the contact holder 6 and pin 8 move in groove 9 at each pole. An arc arises at the open contact, which then extinguishes in the arcing chamber 5. 1 sludge.

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The magnitude and magnitude at the poles may vary. At two adjacent poles, the direction of the currents may coincide and may be opposite. Therefore, contact holders 6 movable 2 contacts in these two poles can either be attracted or repelled.

Consider the operation of the device at the specified directions of currents in the poles.

Since the currents in the left and middle poles are opposite in direction, the contact holders 6 of the moving contacts 2 repel each other, with the result that the upper contacts of the left pole and the lower contacts of the middle contact open, and an arc along the arcing horns 4 enters the arcing chamber 5. Other pairs of contacts in these poles are pressed against each other due to the indicated interaction forces of the contact holders and the presses from the contact springs 7 and the contact holders 6 are movable relative to their contact line. x contacts 2, the pins 8 of which in this case move in the slots of the insulating body 1.

Let us consider how the currents in poles can be distributed in magnitude. This is of interest for analyzing the operation of the middle pole if the current direction in it is opposite to the direction of the current in two adjacent poles. In this case, it is understood that the duration of current flow is determined by the time of circuit disconnection by a switch and is no more than a half-cycle of current 50 Hz.

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a single half-period, the equality of the current of the poles is extremely small. therefore

two extreme poles may be the power of the occurrence of conditions

specific point in time. Therefore, it is suitable for welding the contact equality of the forces acting on the contacts for the proposed device

The holder of the middle pole with a side-less than that of the known extremes of the extreme poles, can only be Vaiupz x devices, in which at only a certain point in time. What are the electrodynamic forces involved in the impulse forces during the protector current of the busbar in the pole, the current passing through, - | Q

Claims (1)

the formula of the invention, the motion of the contacts, then the value of the extreme poles will be a Current-limiting device always different And this means that the automatic circuit breakers, which provide the impulse of forces to the contact-holding insulating body, the contact pole and the arc-suppressive pole are always directed to the center pole of the middle pole, the contact poles Well, one of these poles, vizin contacts with springs, so that, at any phases of contact pressing, and the voltage at which 20 moving contacts are located on a short circuit, the opposite ends of their common operation are ensured. Moreover, due to the contact holder and the opposite use of electrodynamic parties relative to the plane, the projections between the poles at the poles of the contact passing through the longitudinal axis of the contact do not need to make loops from current carriers and parallel flat tires. l and h and - the consumption of materials of the device, Using the fact that, in order to reduce the electrodynamic load of materials and extend between adjacent poles for the separation of the reliability of the contacts, The contacts of the contacts at the pole are significant; the contact holders of the movable contacts of all but reduces the likelihood of poles being set so that their welding conditions for the contacts. As longitudinal axes parallel to each other show research, are greatest and are located in the same plane, the probability of welding will be in the tomperpendicular touch plane if the contact contact us, the contact holder, is only small, that the molten metal-moving contacts of each pole of the contact point when opening, the length between the fixed points of the contacts cannot be further electrodiented by the moving contacts with the direction of the dynamic and gas-dynamic reinforcing pin entering the grooves, which They should be thrown out of the contact zone, 40 carried out in the housing, but at the same time limiting the amount of skip-the ability to move the contact-current current at the moment of dropping the largest-moving contacts in all of the shafts. It is quite obvious that such directions in the plane, perpendicular to the conditions, occur when the maximum plane of the location of the displacement of contacts to be thrown off due to the lines of gny contacts of all poles, but coinciding with the maximum meaning of the possibility of rotation of the main forces contact-breaking contact-moving contacts with the flow of short-circuit current. In relation to the line of contact of one or the proposed current-limiting device — another pair of movable and stationary probes — the probability of coincidence of the max contacts in the plane of the location of the maximum force of the contact contacts in the field of the longitudinal axes of the contact holders with the maximum of the interaction forces of the movable contacts.