JPS63132406A - Electromagnet driving device - Google Patents

Abstract

PURPOSE:To prevent the fusion of the contact point of a making switch by a method wherein an electromagnet operating coil is divided into two parts at a suitable ratio, and one of the divided parts of the coil is inserted into the charging circuit of the capacitor to be used for noise absorption. CONSTITUTION:An electromagnet controlling coil is divided into a coil 51 and a coil 52 at a suitable ratio. The coil 51 is connected to the side of a making switch 2, not on the side of a noise absorbing capacitor 3. As the coil 51 works as a choke coil, the circuit impedance from a power source 1 to the capacitor 3 becomes higher. As a result, the sudden flowing of a charging current to the capacitor 3 at the moment when the making switch 2 is closed can be prevented, and the fusion of the contact point of the making switch 2 can be prevented.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention allows a continuous current to flow through the electromagnet operating coil when the electromagnet is turned on, and a continuous current to flow when the electromagnet is held. The present invention relates to an electromagnet drive device that reduces power consumption by switching to an intermittent current that only maintains the current.

[Prior art]

This type of conventional technology is shown in FIG. 5, in which by turning on the turn-on switch 2, the AC voltage of the single-phase AC power supply 1 is transferred to the AC terminal ζ of a full-wave rectifier circuit 9 consisting of a diode bridge circuit.
This is applied. The DC terminal of the full-wave rectifier circuit 9 is connected to the collector of the electromagnet operating coil 5 and the switching transistor 6.
It is connected to the series circuit of the emitter path and to the drive circuit 7. 3 is a noise absorption capacitor,
4 is a flywheel diode, and 8 is a line inductance. As shown in the time chart of FIG. 6, when the closing switch 2 is turned on, the driving circuit 7 applies continuous pulses to the base of the switching transistor 6 for a certain period of time T necessary for attracting the movable core of the magnet. After the movable core has been suctioned, it is necessary to hold the movable core.
An intermittent pulse of is applied to the base of the switching transistor 6. As a result, an intermittent current is applied to the operating coil 5 of the electromagnet after the movable core is attracted, so that power consumption can be reduced.

[Problem that the invention seeks to solve]

As mentioned above, the switching transistor 6 is operated in a switching operation in order to reduce power consumption, and the capacitor 3 is connected to remove switching noise caused by this switching operation. However, a sudden charging current flows through the capacitor 3 from the power supply 1 through the switch 2 the moment the switch 2 is turned on, and depending on the configuration of the capacitor 3 and the switch 2, the contact point of the switch 2 may This may cause welding and wear of the contacts, and may also cause deterioration of the capacitor 3. When a semiconductor switch such as a 1-11 relay is used as the closing switch 2.

Power supply 1. Switch 2. A series resonance phenomenon occurs due to the capacitor 3 and the line inductance 8, and a reverse voltage is applied to the semiconductor switch, which causes it to be turned on and off again, causing deterioration due to rapid charging and discharging of the capacitor 3 and adversely affecting the operating coil 5. It has the disadvantage of having a negative impact.

Therefore, the present invention eliminates the drawbacks of the conventional device and welds the closing switch contact without adding any parts.

The purpose is to prevent capacitor deterioration and provide a highly reliable electromagnet device.

[Means to solve the problem]

In order to achieve the above-mentioned object, this invention connects a power switch, an electromagnetic operating coil, and a switching element in series with a power supply, and a noise absorbing capacitor is connected in parallel to the operating coil and switching element, In an electromagnet drive device having a drive circuit that supplies continuous pulses to the switching element when the electromagnet is turned on and supplies intermittent pulses when the electromagnet is held, the operating coil is divided into two at an appropriate ratio, and one of the divided The coil was used as a charging circuit for a noise absorbing capacitor.

[Effect]

By dividing the electromagnet operating coil into two at an appropriate ratio and connecting one of the coils to the charging circuit of the noise absorbing capacitor and using it as a choke coil, the circuit impedance from the illumination to the noise absorbing capacitor can be reduced. This prevents charging current from suddenly flowing into the noise absorbing capacitor at the moment the closing switch is turned on.

[Embodiments of the invention]

1 and 3 each show an embodiment of the present invention, and the same components in FIG. 1 as those in the conventional device shown in FIG. 5 are given the same reference numerals, and their explanation will be omitted.

The difference in FIG. 1 from the conventional device shown in FIG. 5 is that the electromagnet operating coils are arranged in an appropriate ratio between coil 51 and coil 5.
The coils 51 and 52 are the power supplies 1. Closing switch 2. The coil 51 is connected in series with the collector-emitter path of the switching transistor 6.
is connected closer to the closing switch 2 than the noise absorbing capacitor 3, the noise absorbing capacitor 3 is connected in parallel to the coil 52 and the collector-emitter path of the switching transistor 6, and the flywheel diode 4 is connected in parallel to the coil 52. It is a connected point. FIG. 3 is a structural diagram of the electromagnet device, in which divided coils 51 and 52 are attached to an E-shaped fixed core, and movable cores 5 and 3 are arranged opposite to each other between the fixed cores.

In FIG. 1, when the closing switch 2 is turned on, the drive circuit 7 supplies continuous pulses with a fixed time width of 1'' and pulses that are intermittent after a fixed time T, as shown in FIG. 2, to the base of the switching transistor 6. . During the electromagnet closing operation in which continuous pulses are applied from the drive circuit 7 to the base of the switching transistor 6, the coil 51
, 52 have a current of equal value i1. i2 flows. This causes a large attractive force to act on the movable core of the electromagnet, which attracts it to the fixed core, completing the closing operation. After the closing operation is completed, intermittent pulses are applied from the drive circuit 7 to the base of the switching transistor, and when the switching transistor 6 starts the switching operation, the capacitor 3 is connected to the coil 5 while the switching transistor 6 is on.
A charging current flows through the capacitor 1, and the capacitor 3 is charged while the switching transistor 6 is off.
Il 52 f Intermediate.

The coil 52 performs the holding operation of the electromagnet. Since the coil 51 is inserted closer to the closing switch 2 than the capacitor 3, the coil 51 acts as a choke coil, so the circuit impedance from the power supply 1 to the capacitor 3 becomes high, and as a result, the moment the closing switch 2 is turned on. Since a charging current does not suddenly flow through the capacitor 3, the contacts of the closing switch 2 are not welded.

If the operating coil is divided into the coil 51 and the coil 52 at a ratio of 1:1, a difference will occur in the current flowing through each coil 51, 52i during the holding operation of the electromagnet. This is because a flywheel diode is connected to the coil 52, so the current flowing through the coil 52 is larger than the current flowing through the coil IX, which acts as a choke coil.

For this reason, there is a difference in temperature rise between the coils 51 and 52, so it is preferable to reduce the ratio of the coil 51 acting as a choke coil.

FIG. 5 shows another embodiment of the present invention, and in this figure as well, the same parts as shown in FIG. 1 are given the same reference numerals. In FIG. 5, a coil 51 acting as a choke coil is connected to the AC side.

A noise absorbing capacitor 3 is connected in parallel to the power supply 1. In this embodiment as well, the operation of the electromagnet device is the same as that shown in FIG. 1, so its explanation will be omitted, but the coil 51 acts as a choke coil and can increase the circuit impedance from the power source 1 to the capacitor. .

〔Effect of the invention〕

As explained above, by dividing the electromagnet operating coil into two at an appropriate ratio and inserting one of the divided coils into the charging circuit of the noise absorbing capacitor, noise can be removed from the power supply without adding any parts. The line impedance up to the absorption capacitor can be increased, and the current that flows when the closing switch is turned on can be limited by a coil that acts as a divided choke coil, which prevents welding of the closing switch contacts and deterioration of the capacitor. can be prevented. Further, by selecting appropriate values for the inductance and resistance of the coil that acts as a choke coil, it is possible to prevent the occurrence of the series co-photographing phenomenon.

[Brief explanation of the drawing]

Figures 1 and 3 each show an embodiment of the present invention, Figure 1 is a circuit diagram of an electromagnet and a vomiting device, Figure 2 is a waveform diagram of a main part, and Figure 3 is a configuration of a main part of an electromagnet device. 4 are circuit diagrams showing different embodiments of the present invention, and FIGS. 5 and 6 are circuit diagrams and waveform diagrams showing conventional devices, respectively. ]: Power supply, 2: Turn-on switch, 3: Capacitor, 6:
Switching transistor, 7: Drive circuit, 51, 52
:coil. Tomi 20 Figure 3

Claims (1)

[Claims] 1) A closing switch, an electromagnet operating coil, and a switching element are connected in series to the power supply, a noise absorbing capacitor is connected in parallel to the operating coil and the switching element, and a continuous pulse is generated when the electromagnet is turned on to the switching element. In an electromagnetic drive device having a drive circuit that supplies intermittent pulses during holding, the operating coil is divided into two at an appropriate ratio, and one of the divided coils is used as a charging circuit for a noise absorption capacitor. An electromagnetic drive device characterized by being inserted.