JPH051886Y2 - - Google Patents

Description

[Detailed explanation of the idea] Industrial applications This invention relates to electromagnetic devices for circuits and breakers.

BACKGROUND ART Conventionally, oil dump pots have been mainly used as electromagnetic devices for circuit breakers.

Fig. 4 shows a conventional oil doss pot. In the figure, 1 is a container. Inside this container 1 is oil 13, which is usually used silicone oil, and a plunger is sealed inside this container 1. 2 is pressed by a spring 3.

Reference numeral 4 indicates an excitation coil that can be wound around the container 1, 5 indicates a movable iron piece, and 6 indicates a spring provided between the movable iron piece 5 and the yoke 7. Further, 8 is a magnetic pole provided at the upper end of the container 1. When current flows through the excitation coil 4, the plunger 2 gradually rises in the container filled with oil 13, and when the plunger 2 rises and comes into contact with the magnetic pole 8, the yoke 7, the plunger 2, and the magnetic pole 8 cause the plunger 2 to rise. A circuit is formed, and the movable iron piece 5 is attracted against the force of the spring 6, and due to the movement of the armature, other devices (not shown), such as a shear breaker device, are actuated as the movable iron piece 5 moves. It is.

It has also been proposed to provide a plug body 5 with a protruding rod 6 in the through hole 3 of the plunger 2 as in Japanese Utility Model Application No. 50-25057, but the effect of this plug body 5 is that the current of the coil 13 is When the plunger 2 is about to return to the bottom of the cylinder 1 after being cut off, the plug body 5 opens the through hole 3 and reduces the oil braking to hasten the return of the plunger 2. Also, in terms of structure, the plug body 5 and the protruding rod 6 are housed in the plunger 2,
It will not fall off at the stopper 7, and will not come out of the plunger 2 and elicit other effects.

Problems to be Solved by the Invention Figure 5 is a diagram showing various characteristic curves, with time on the vertical axis and full load current on the horizontal axis, where a is the fuse blowing characteristic curve and b is the general purpose one. The characteristic curve of the electromagnetic device for circuit breakers and breakers, c, shows the ideal characteristic curve of the electromagnetic device of this invention. Curve b is the characteristic of general circuits and circuit breakers, but the intersection of curves a and b is Q.
1 and Q2, the b curve protrudes to the right side of the a curve between Q1 and Q2, causing the inconvenience that the fuse blows out first. If the length of the plunger 2 is unavoidably adjusted, the lower frequency band will be cut off within the rated current due to the left side, which will cause another inconvenience.

Means for Solving the Problems With these points in mind, the inventor tried various prototypes and experiments, and as a result of this invention, the through hole 12 was drilled in the center of the plunger 2, as shown in Fig. 1. A brake rod 10 having a head 11 passes through the through hole 12, and a cylindrical brake member 9 made of a non-magnetic material is sealed together with silicone oil 13 in a container 1, similar to the plunger 2, with a slight gap between the brake rod 10 and the container 1. The flow of the silicone oil 13 acts as a brake when the plunger rises together with the plunger 2, and has a long time delay.

Operation When the overload current flowing through the excitation coil 4 is a medium current, the brake element 9 made of a non-magnetic material remains in the same position, but the plunger 2 gradually rises along with the brake rod 10, If sufficient leakage flux is generated before the plunger 2 reaches the stop 11 as shown in FIG. 2, the movable iron piece 5 will be attracted by the magnetic pole 8. Further, when the overload current flowing through the excitation coil 4 is small, that is, in the low range region around 125%, the plunger 2 gradually rises as shown in FIG. 3, hits the stop head 11, and closes the through hole 12.
While stopping the flow of the silicone oil 13, it further rises and pulls up the brake 9 as well, reaching the maximum delay state and hitting the magnetic pole 8, causing the magnetic pole 8 - movable iron piece 5
A magnetic path is formed between - yoke 7 and the plunger 12, and the movable iron piece 5 is attracted by a sufficient magnetic force generated despite a small current. Furthermore, the low frequency delay characteristic is improved by the brake 9.
This can be adjusted arbitrarily by adjusting the length of the brake rod 10. The longer the brake rod 10 is, the later the braking of the brake element 9 will be, so the time delay characteristic will be faster, and the shorter it is, the longer the time delay will be. Become. Further, the middle range time delay characteristic can be adjusted as desired by changing the diameter of the through hole 12 of the plunger 2. In other words, in the case of a low current, the suction to the plunger 2 is weak, so there is little flow friction of the silicone oil 13 flowing through the through hole 12, so there is little effect, but in the case of a medium current, the suction force is stronger, so the through hole 12 is less affected. If the diameter is small, the flow friction will be large and the time delay will be extended.

Embodiment FIG. 1 is a side sectional view of an electromagnetic device for a circuit breaker according to this invention, and FIGS. FIG. 3 is a partial cross-sectional view of the electromagnetic device of the circuit and the circuit breaker, showing the moving states of the circuit and the circuit breaker.

In FIG. 1, 1 is a container made of a non-magnetic material, and 2 is a plunger made of a magnetic material. A through hole 12 is bored in the center. A brake rod 1 having a stop head 11 is installed in the through hole 12.
0 is inserted and penetrated, and is connected to a cylindrical brake 9 made of a non-magnetic material, and the plunger 2 and the container 1 are connected to each other.
sealed inside. 5 is a movable iron piece, 7 is a yoke, and a spring 6 is provided between the two, and the movable iron piece 5 is biased clockwise by this spring 6. 4 is an excitation coil. Next, to explain the operation, if the overload current flowing through the excitation coil 4 is a medium current, the brake 9 remains as it is;
The plunger 2 gradually rises along the brake rod 10, and when the plunger 2 reaches the vicinity of the stop 11 and sufficient electromagnetic force is generated to attract the movable iron piece 5 as shown in FIG. It is strongly attracted by the magnetic pole 8. In this case, since the silicone oil 13 passes through the through hole 12 when the plunger 2 is raised, the time delay becomes faster, so Q1, Q2, and 2 of the curve b
The portion shifts to the left and approaches curve c in Figure 5. In addition, when the overload current flowing through the excitation coil 4 is small, that is, in the low range region around 125%, the plunger 2 gradually rises as shown in FIG.
When it hits, it moves up further while closing the through hole 12, and pulls up the brake 9 together with it, and after the maximum delay time, it comes into contact with the magnetic pole 8 and attracts the movable iron piece 5. That is, even though the delay time is increased when the overload current is medium, the delay time is sufficiently long in the low band, so that the ideal curve c in FIG. 5 can be obtained. In the experiment, the distance 1 between the magnetic pole 8 and the stop head 11 was
When it was set near 200%, an ideal c-curve could be obtained.

Effects of the invention As described above, this invention provides a wider range of time delay characteristics than the conventional plunger type overload current electromagnetic device using one element. That is, in addition to selecting the viscosity of the silicone oil, the time delay characteristics of the electromagnetic device according to this invention can be adjusted arbitrarily by adjusting the lengths of the brake element 9 and the brake rod 10, and the time delay characteristics in the middle range can be adjusted as desired. can be arbitrarily adjusted by changing the diameter of the through hole 12 of the plunger 2.

Therefore, by using the electromagnetic device according to this invention, it is possible to easily obtain a curve c that is in harmony with the characteristic curve a of the fuse, which has a great industrial effect.

[Brief explanation of the drawing]

FIG. 1 is a side cross-sectional view of the electromagnetic device for circuit breakers and circuit breakers according to this invention, and FIGS. 2 and 3 show the state of movement of the plunger 2 and brake 9 as the excitation coil 4 is excited. FIG. 4 is a side sectional view of a conventional circuit breaker electromagnetic device, and FIG. 5 is a comparison diagram of ideal characteristic curves according to the conventional and this invention. In the figure, 1 is a container, 2 is a plunger, 3 is a spring, 4 is an exciting coil, 5 is a movable iron piece, 6 is a spring,
7 is a yoke, 8 is a magnetic pole, 9 is a brake, 10 is a brake rod, 11 is a stop, 12 is a through hole of a plunger, 1
3 is oil.

Claims (1)

[Scope of utility model registration request] Oil 13 is sealed in a container 1, and a magnetic plunger 2 is housed in the container 1 while being pressed downward by a spring 3. A movable iron piece 5 is installed using an excitation coil 4 that can be wound around the container 1. In a circuit and disconnector that sucks against a spring 6, a through hole 12 is formed in the vertical center of the plunger 2 and a stop head 1 is provided.
1 with a brake rod 10 at the upper end, extend the lower end of the brake rod 10, connect it with a cylindrical brake 9 made of a non-excitable material, and insert it into the container 1 together with the plunger 2. An electromagnetic device for a circuit breaker, characterized in that the time delay characteristic of the electromagnetic device can be arbitrarily adjusted by adjusting the lengths of a brake element 9 and a brake rod 10 by sealing the device.