JPH057435Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention relates to the wiring structure of a reverse phase prevention relay switch in an electric switchgear such as an electric shutter installed at the entrance/exit of a building or a show window. .

[Problems to be solved by the prior art and the invention] In general, electric opening/closing machines such as electric shutters raise, lower, and stop the shutter curtain by driving and controlling an electric motor by operating a push button switch or the like. It's summery. In this case, the electric motor may be a three-phase AC motor, but in this case, there is a risk that a wiring error may occur during construction or repair of a building and the connection will be in the opposite phase. For this reason, a reverse phase prevention relay device is provided in the drive control circuit to prevent accidents due to reverse rotation of the motor.

However, conventionally, the reverse phase prevention relay device 5
As shown in the figure, a resistor R, a capacitor C, and an excitation coil L of an electromagnetic relay are Y-connected to each phase of the power supply.
are wired in parallel, and when the power is turned on, the load voltage of the excitation coil L changes significantly depending on the direction of phase rotation, and when the reverse phase connection is made, the relay switch Ra has been developed to regulate motor drive. However, this one is the main switch.
When the KS is inserted, the reverse phase prevention relay device is always in a closed state with current flowing through it, which has the disadvantage of shortening the life of the capacitors, relay coils, etc. that make up the reverse phase prevention relay device. It's becoming a problem.

[Means for solving the problems] In view of the above-mentioned circumstances, the present invention was devised for the purpose of providing a wiring structure for a reverse phase prevention relay switch in an electric switchgear that can eliminate these drawbacks. In an electric switch, the power supply circuit of the three-phase motor is provided with a reverse phase prevention relay switch whose switch contacts open to prevent the three-phase motor from driving when the three-phase motor is connected to the reverse phase. A switch contact is activated by the closing operation of the on-off switch provided in the on-off switch circuit between the on-off switch circuit for forward and reverse driving of the three-phase motor and any phase line of the three-phase power supply. A line is connected to a main relay switch such that the main relay switch is closed, and a switch contact of the main relay switch is connected to a line between the reverse phase prevention relay switch and the power supply circuit of the three-phase motor. Connecting a switch contact of a phase prevention relay switch to a line between a switch contact of an opening/closing relay switch that is activated based on a closing operation of the opening/closing switch circuit to close the power supply circuit and the opening/closing switch circuit, The present invention is characterized in that the reverse phase prevention relay switch is configured to be energized in conjunction with the closing operation of the opening/closing switch circuit.

With this configuration, the present invention prevents voltage from being applied to the reverse phase prevention relay device except when the shutter curtain is opened or closed.

[Example] Next, an example of the present invention will be described based on the drawings. In the drawings, reference numeral 1 denotes an electric shutter, and the electric shutter 1 moves a shutter curtain 3 along a guide rail 4 by forward and reverse driving of an opening/closing machine 2.
The opening is opened and closed by moving up and down while being guided by the user. FIG. 2 shows a circuit diagram for controlling the elevation. Here, R,
S and T are each phase of the three-phase AC power supply, M is the motor, MB is the brake, E is the power supply, KS is the main switch, F is the fuse, PBU, PBD, and
PBS is a push button switch for raising, lowering, and stopping, respectively. EMS is an emergency stop switch, and LSU and LSD are limit switches for upper and lower limits, respectively.
RYU and RYD are the relay switches for raising and lowering, respectively, and their switch contacts, and these are all wired using conventional circuits.

5 is a main relay switch, and the main relay switch 5 is connected to a push button switch circuit for raising and lowering (PBS-PBU or PBS-PBD) from the phase T power supply circuit.
One end is connected to terminals B2 and B4 before reaching relay switch RYU or RYD via a diode D, and the other end is connected to the phase R power supply circuit.

On the other hand, 6 is a reverse phase prevention relay device, and the capacitor 7, the excitation coil 8 of the electromagnetic relay, and the resistor 9 that constitute the reverse phase prevention relay device 6 are the same as the conventional ones described above. Phase R, S,
However, switch contacts 5a, 5b, 5c of the main relay switch 5 are connected to the lines between the capacitor 7, the excitation coil 8 of the electromagnetic relay, the resistor 9, and each phase R, S, and T. Each is provided. And push button switch PBU for raising and lowering,
By pressing the PBD and closing the circuit from phase T to phase R of the main relay switch 5, the switch contacts 5a, 5b, 5c are closed and the reverse phase prevention relay device 6 is energized. ing.

In addition, the switch contact 6 of the reverse phase prevention relay device 6
Terminals B2, B4 are connected to the relay switches RYU, RYD for rising and falling, and upper and lower limit switches LSU, LSD for falling, and are connected to the switch contacts RYU, RYD of the relay switches for rising and falling on the power supply side.
The load voltage of the excitation coil 8 of the reverse phase prevention relay device 6 drops significantly, and the switch contacts 6a, 6b
are kept in an open state, so that in the reverse phase connection, the motor M will not be driven even if the up and down push button switches PBU, PBD are pressed.

In the embodiment of the present invention configured as described above,
Complete the installation or repair of the shutter, complete the necessary wiring to the power source for operation, raise the shutter,
When the lower push button switches PBU and PBD are pressed, the motor M will be driven if the wiring is correct, but if the reverse phase connection is made, the motor M will not be driven.

In other words, when the up/down push button switch PBU or PBD is pressed, if the wiring is correct,
As mentioned above, the circuit of main relay switch 5 is closed,
As a result, the switch contacts 5a, 5b, and 5c are closed, and the reverse phase prevention relay device 6 is energized. Then press the stop push button switch PBS, or
When the shutter curtain moves to the upper or lower limit and the upper and lower limit switches LSU and LSD open, and the motor M stops, the circuit of the main relay switch 5 also opens at the same time, and the switch contact 5a, 5b and 5c are opened, and energization to the reverse phase prevention relay device 6 is stopped.

As described above, in the present invention, although the reverse phase detection is performed by the reverse phase prevention relay device 6, the reverse phase prevention relay device 6 is
Since no current is applied when the relay is stopped, the life of the negative phase prevention relay device is significantly longer than that of the conventional relay device in which current is constantly applied.

Moreover, in the embodiment, the main relay switch 5
Since it is Y-connected via two diodes D, it can be used for rising and falling, which has the advantage of simplifying the structure and reducing the number of parts.

It should be noted that the present invention is of course not limited to the above embodiment, but even if the switch contacts of the main relay switch 5 are provided at two locations, it is difficult to energize the reverse phase prevention relay 6. can be cut off.

[Operations and Effects] In summary, since the present invention is constructed as described above, it is possible to check whether or not the connection between the three-phase motor and the power supply circuit is in reverse phase using a reverse phase prevention relay device. Although the motor is not driven in the case of a reverse-phase connection, the power to this reverse-phase prevention relay device must be operated by operating an on/off switch. The lifespan of the reverse phase prevention relay device is significantly longer than that of conventional relay devices, and safety can be improved.

[Brief explanation of the drawing]

The drawings show one embodiment of the wiring structure of the reverse phase prevention relay switch in the electric switchgear according to the present invention, in which Fig. 1 is a schematic front view of the electric shutter, and Fig. 2 is a diagram of the elevation control circuit mechanism. Circuit diagram, 3rd
The figure is a circuit diagram of a conventional lift control circuit mechanism. In the figure, 1 is an electric shutter, 2 is a switch, 5 is a main relay switch, 5a to 5c are the switch contacts, and 6 is a reverse phase prevention relay device.

Claims (1)

[Scope of utility model registration request] In an electric switch, the power supply circuit of the three-phase motor is provided with a reverse-phase prevention relay switch that opens a switch contact to prevent the three-phase motor from driving when the three-phase motor is connected in reverse phase. A switch is installed between the open/close switch circuit for driving the motor in forward and reverse directions and any phase line of the three-phase power supply, and the switch contact closes when the switch is closed. A line is formed to which a main relay switch is connected, and a switch contact of the main relay switch is connected to a line between the reverse phase prevention relay switch and the power supply circuit of the three-phase motor; The switch contact of the switch is connected to the line between the switch contact of the on-off relay switch, which is activated based on the closing operation of the on-off switch circuit and closes the power supply circuit, and the on-off switch circuit to prevent reverse phase. 1. A wiring structure for a negative phase prevention relay switch in an electric switchgear, characterized in that the relay switch is configured to be energized in conjunction with the closing operation of the open/close switch circuit.