JPH0221089B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an improvement in an instant return type electromagnetic trip device.

Prior Art A conventional instant return type circuit breaker is shown in FIG. 4, in which a cylindrical pipe 1 is fitted into an L-shaped magnetic frame (yoke) 8, and an electromagnetic coil is attached to the outer periphery of the cylindrical pipe 1. Wearing 11,
A plunger 2 that can move up and down along the cylindrical tube 1 is combined with a spring 4, and further contains oil 3, and a hole 7 that can be penetrated up and down along the axis is bored in the plunger 2. A ball valve 6 is installed on the edge of the hole 7, and a stopper rod is attached to prevent the balls of the ball valve 6 from flying out. In addition, a magnetic pole piece 5 is provided on the upper end surface of the cylindrical tube 1, and an armature 9, which is biased by a spring 10, is provided on the L-shaped yoke 8 facing the magnetic pole piece 5.

Thus, when an overcurrent flows through the electromagnetic coil 11, the electromagnetic force acting on the plunger 2 increases, and the plunger 2 is attracted and raised against the spring 4. The through hole 7 bored in the plunger 2 at this time
The oil 3 tries to flow through the oil 3, but the ball valve 6 is pushed down by the oil flow and comes into close contact with the upper end of the through hole 7, thereby blocking the flow, and the plunger 2 receives resistance and slowly moves or rises.

Next, when the electromagnetic coil 11 becomes de-energized and loses its electromagnetic force, the plunger 2 descends due to its own weight or the force of the spring 4, and the ball valve 6 is pushed up by the action of hydraulic pressure, and the upper end of the through hole 7 opens to allow oil to flow through the hole. This improves the flow of oil, reduces the resistance of the oil acting on the plunger 2, and the plunger 2 quickly descends and returns to its original position.

Problems to be Solved by the Invention The electromagnetic tripping device having the plunger 2 which is braked by oil in this manner is used in a motor circuit, etc. so as not to react to a short-term overcurrent such as a starting current. At the same time, in the case of an elevator where the electric motor is repeatedly started and stopped, the time required for the overcurrent to pass is accumulated and a response is required. In the case of the present invention, it is desirable that the plunger 2 moves slowly when attracted by electromagnetic force, but moves rapidly when returning. If the electromagnetic part shown in Fig. 4 is used horizontally with respect to gravity (if it is used vertically, gravity acts on the plunger 2, and even a slight change in the mounting angle will change the characteristics), the ball valve 6 as shown in Fig. 3 is used. Due to the weak flow, it takes time to climb up the slope at the entrance of the hole 7 and prevent the through hole 7, and the operation is very complicated, and even if it is closed, if it is an alternating current, the oil may leak due to electromagnetic vibration. , is unstable. To this end, there were plans to prevent leakage by providing a pressure spring 15 on the ball valve 6 as shown in Figure 2, or by magnetizing the ball valve to make it easier to adhere to it, but the electromagnetic coil 11 was de-energized and the ball If the valve 6 opens, it will create resistance, which is very inconvenient, and it is difficult to adjust the strength of the push spring and magnetization to prevent this, making it unsuitable for mass production.

Means for Solving the Problems In consideration of the above points, the present invention has repeatedly carried out trial production and experiments to provide a stable instant return type tripping device that performs accurate valve action.

That is, in the present invention, the lower part of the plunger 2 is slightly shaved to make the diameter narrower, and the cylindrical body 13 made of a non-magnetic material is lightly fitted into the slightly narrower diameter part, and connected to the ball valve 6 by a connecting line 12, so that the upper and lower parts can be connected to each other. It can be slid freely.

By doing so, it is possible to obtain an instant return type tripping device that ensures reliable valve action even with a weak oil flow force and has stable characteristics regardless of the mounting angle.

Embodiment Next, a device according to an embodiment of the present invention will be described with reference to FIG. 1, and for convenience of explanation, the same parts in FIG. 4 will be indicated by the same reference numerals. An electromagnetic coil 11 is attached to the outer periphery of the cylindrical tube 1, and a plunger 2 that moves up and down along the cylindrical tube 1 is combined with a spring 4, and further contains oil 3, and the plunger 2 has a shaft. A hole 7 that can be penetrated vertically along the center is bored, and a ball valve 6 made of a non-magnetic material is housed in the mouth edge of the through hole 7. In addition, a magnetic pole piece 5 is provided on the upper end surface of the cylindrical tube 1, and an armature 9 that is biased by a spring 10 to an L-shaped yoke 8 is provided opposite to the magnetic pole piece 5.

Furthermore, in the present invention, the lower end of the plunger 2 is slightly shaved to make the diameter slightly narrower, and a ball valve made of a non-magnetic material is attached to the center of the bottom of the cylindrical body 13 made of a non-magnetic material to make the outer diameter of the plunger 2 the same as that of the plunger 2. 6 is a cylindrical body 13 that is connected by brazing with a non-magnetic wire 12 that can pass through the through hole 7.
The structure is such that the ball valve 6 is opened and closed according to the vertical movement of the ball valve 6. Reference numeral 14 denotes a plurality of oil discharge holes provided at the bottom of the cylindrical body 13.

Next, the electromagnetic tripping device according to the present invention will be explained. When an overcurrent flows through the electromagnetic coil 11, the electromagnetic force acting on the plunger 2 increases and the plunger 2 is attracted, but the cylindrical body 13 is a non-magnetic material. Therefore, the ball valve 6 connected by the connecting line 12 is pulled by the flow of oil passing through the gap between the plunger 2 and the cylindrical pipe 1 and the through hole, and is securely connected to the through hole 7.
is closed.

Next, when the electromagnetic coil 11 is no longer energized, the attractive force disappears and the plunger 2 tries to return due to the return spring 4, causing the cylinder 13 to fully open the ball valve 6 due to the flow, and the oil passes through the through hole 7 and the discharge hole 14. and rapidly recur.

Effects of the Invention In the trip device of the present invention, the ball valve 6 is operated by the cylindrical body 13 which is operated by sufficiently receiving the flow action of the oil, so the valve action is reliably performed even with a weak flow force. An instant return type tripping device with stable characteristics regardless of the current condition can be obtained.

That is, in the present invention, the plunger moves slowly when attracted by electromagnetic force, but moves quickly when returning.

[Brief explanation of drawings]

FIG. 1 is a side sectional view of an embodiment of a trip device according to the present invention, and FIGS. 2, 3, and 4 are side sectional views of different embodiments of a conventional trip device. In the figure, 1 is a tube, 2 is a plunger, 3 is oil, and 4
is a return spring, 5 is a magnetic pole piece, 6 is a ball valve, 7 is a through hole, 8 is a yoke, 9 is an armature, 10 is a spring, 11 is an electromagnetic coil, 12 is a connecting wire, 13 is a cylinder, 14 is oil Exhaust hole.

Claims (1)

[Claims] 1. A hole 7 that can be penetrated vertically along the axis is bored in the cylindrical tube 1 in which the electromagnetic coil 11 is wound.
In an electromagnetic trip device in which a plunger 2, a return spring 4, and an oil 3 are housed in combination, a ball valve 6 made of a non-magnetic material is accommodated in the mouth edge of the plunger 2, and the cylindrical pipe 1 is fitted into an L-shaped magnetic frame 8. , the lower end of the plunger 2 is slightly shaved to make the diameter slightly narrower, and the ball valve 6 is connected to the center of the bottom of the cylindrical body 13 made of a non-magnetic material, which has the same outer diameter as the plunger 2. An instant return type electromagnetic tripping device characterized in that by connecting a non-magnetic connecting wire 12 passing through the through hole 7, stable and immediate return with accurate valve action can be achieved.