JPS594426Y2 - Overcurrent detection device - Google Patents

Description

[Detailed explanation of the idea] This invention relates to an overcurrent detection device.

An embodiment of the present invention will be described below with reference to the drawings. Reference numeral 1 denotes a U-shaped yoke, which is fixed to the casing 2.

Reference numeral 3 denotes a salient magnetic pole having a through hole 4 on its central axis, one end of which has an outer circumferential body fixed through the mounting hole 5 of one end plate 1a of the yoke 1, and the salient magnetic pole 3 is provided to protrude from the inner surface of the one end plate 1a. .

Reference numeral 6 denotes a guide tube made of a magnetic material that is fixed through the attachment hole 7 of the other end plate 1b of the yoke 1, and 8 is a movable iron core having a through hole 9 on the central axis, and the outer peripheral side of the base end thereof is a guide tube. The movable iron core 8 is slidably inserted into the shaped body 6, and the front end surface of the movable iron core 8 is opposed to the magnetic pole surface at the front end of the salient magnetic pole.

10 is a spring compressed between the movable iron core 8 and the salient magnetic pole 3;
Reference numeral 11 denotes a drive rod made of a non-magnetic material having a locking step 12 in the middle portion, and the proximal end of the rod 11 is slidably inserted into the through hole 9 of the movable iron core 8 and locked. The tip end side of the stepped portion 12 is inserted through the through hole 4 of the salient magnetic pole 3 .

Reference numeral 13 denotes a recess into which the locking step portion 12 is inserted, and is formed in at least one of the magnetic pole surface at the tip of the salient magnetic pole and the tip surface of the movable iron core 8.

14 is a coil wound around the outer circumferential side of the salient magnetic pole 3 and the outer circumferential side of the movable iron core 8; 15 is a bimetal whose base end is fixed to the housing 2; its free end side surface is connected to the base end of the drive rod 11; The free end of the bimetal 15 is connected to one end of the coil 14 by a lead wire.

This proposal has the above configuration, with bimetal 15 and coil 1.
4 are connected in series to a distribution line, and when an overcurrent of a certain level or more flows through the distribution line, the bimetal 15 is heated by the overcurrent flowing through it, and its free end is bent, causing the drive rod 11 to exceed a certain level. An overcurrent in the power distribution line can be detected by pressing and moving the drive rod 11 beyond a certain level.

Next, when a short circuit current flows through the wiring, the magnetic flux created by the short circuit current flowing through the coil 14 causes the movable iron core 8 to move to the salient magnetic pole 3.
The drive rod 11 is pressed and moved by the movement of the movable iron core 8, and the short-circuit current of the distribution line can be detected by the movement of the drive rod 11.

By moving the drive rod 11, a circuit breaker connected in series to the power distribution line can be opened.

Note that when the bimetal 15 is heated and bent by the overcurrent and then allowed to cool naturally, the bimetal 15 bends in the opposite direction, and the driving rod 11 is in a free state without receiving any external force, and the movable iron core is also bent due to the short circuit current. When the short circuit current disappears after the salient magnetic pole 8 is attracted to the salient magnetic pole 3, the movable iron core 8 is separated from the salient magnetic pole by the spring force of the spring 10, and the drive rod 11 is free from any external force.

In this way, in normal times, the drive rod 11 is in a free state without receiving any external force, and therefore the drive rod 11 is reset by the tripping section of the circuit breaker or the like.

The drive rod is driven to move in the axial direction by the bending of the free end of the bimetal, and is also driven to move in the axial direction by the movement of the movable core, so it can be constructed compactly, and the drive rod is always moved in the axial direction. When the circuit breaker is opened by moving the driving rod, the point of action of the driving rod on the circuit breaker coincides, making it easy to interlock multiple poles and stabilize operation of the circuit breaker. It has the effect of being done.

[Brief explanation of the drawing]

The drawing is a sectional view of an embodiment of the present device. 1 is a yoke, 2 is a housing, 3 is a salient magnetic pole, 4 and 9 are through holes, 6 is a guide tube, 8 is a movable iron core, 10 is a spring, 11 is a driving rod, 12 is a locking step, 14 is a coil.

Claims (1)

[Scope of utility model registration request] The yoke 1 is fixed to the casing 2, and one end of the salient magnetic pole 3 having the through hole 4 in the central axis is fixed through the mounting hole 5 of the one end plate 1a of the yoke 1, and the guide cylindrical body 6 is attached to the yoke 1. Other end plate 1
The outer circumferential side of the proximal end of the movable core 8, which is fixed through and fixed to b, and has a through hole 9 in the center, is slidably inserted into the guide cylinder 6, and the distal end surface of the movable core 8 is inserted into the distal end of the salient magnetic pole 3. A locking stepped portion 12 of a drive rod 11 which faces the surface, is elastically loaded with a spring 10 that separates the movable iron core 8 from the salient magnetic pole 3, and has a locking step portion 12 at the intermediate portion.
The proximal end is slidably inserted into the through hole 9 of the movable core 8, and the distal end is slidably inserted into the through hole 4 of the salient magnetic pole 3 from the locking step portion 12. and salient magnetic pole 3
A coil 14 is wound around the outer circumferential side of the bimetal 14, and the free end side surface of a bimetal 15 whose base end is fixed to the housing 2 faces the base end of the drive rod 11, and the free end of the bimetal 15 is connected to one end of the coil 14. An overcurrent detection device connected to the lead edge.