DE281109C - - Google Patents

Description

IMPERIAL

PATENT OFFICE.

PATENT LETTERING

- JiS 281109- CLASS 21 c. GROUP

CARL GUSTAV GSELL in BERLIN.

Electromagnetic switching device for electric motors.

Patented in the German Empire on April 17, 1913.

With the previous reversal of DC motors, it was always necessary to have four Lines and five lines between the engine and the starter system for final switch-offs to lay.

In systems where the motor is far away from the control apparatus (e.g. cranes, Elevators ο. Like.) or where the motor with the control unit by sliding contacts

ίο is connected, makes the large number of lines, all of which are traversed by the entire motor current in the main current motor, or In the case of sliding contacts, the large number of these causes considerable additional costs for the system. Yes, in the case of electric suspension railways is the accommodation of such a large number of pantographs mostly impossible, especially with automatic limit switch-off.

The invention reduces the lines, but without affecting the rapid switching of the motor. This is achieved by arranging an electromagnetic switch, the excitation coil of which is directly fed by the motor leads (between starter and motor). The introduction of a limit switch is possible without any further line. .
The mode of action is as follows:
Assume that the motor is to rotate in position I of the controller 9 on the left and in position II on the right (FIG. 1). The current will flow in the first case: from 9 (brought to position I) through resistor I, 13, magnet 10 to the - pole. The coil of the reversing magnet 10 picks up and closes contacts 1, 2, 3, 4. The current now divides before 13 and also goes to:

2, ι through the armature 11 of the engine according to 4, 3, Field 12 of the motor back to -—Pol. The limit switch 13 would only have in this case disconnecting the coil current of 10 can therefore be kept very small.

If the motor is to run clockwise, crank 9 is set to II. The current makes the way: from the + pole to 9, II, 6, 5 in the opposite sense through the armature 11, 7, 8 (since the magnet 10 is not excited at all and the core is not attracted) to 12 to the —- Pol. Switches 1 to 8 are advantageously designed as a contactor to prevent switching to interrupt the current safely with blowing.

Instead of the four-pole magnetic switch, two double-pole or four single-pole Contactors are used, with 1 or 2 contactor coils even with clockwise rotation of the motor are excited and only cause the motor to short-circuit. The four single-pole contactors have two excitation coils connected in parallel and each two coils fed by a supply line.

In Fig. 2, for. B. the circuit represented by two double pole contactors. The flow of electricity takes place in this case when the starter 22 is set to I: from + pole, 22, 24, - pole; Before entering the magnetic coil 24, the current divides, goes to 17, 16 (since coil 24 contacts 14, 15, 16, 17 closed). From 16 the current continues to the armature 25, after 15,14, the field 26 after the —Pole. Intended to If the engine is running in the other direction of rotation, the starter 22 is switched to II and finds a current flow instead of: + pole, 22, 27, 23

after the pole; at 27 (limit switch) divides

the current and flows, since coil 23 has closed contacts 18, 19, 20 and 21, from 27 to 21, 20 after anchor 25, in the opposite sense than before, after 18, 19, 26, the —Pol.

The coil 10 or 23, 24 is to be wound in such a way that, for. B. at a mains voltage of 110 volts the magnetic core is attracted to 110 volts and still holds safe on the first control creation, that is at about 20 volts. There like that operated motors almost always work intermittently, so the magnetic coil ίο can be very small.

However, there is no obstacle to the aforementioned circuit also for continuous operation use. In this case, small carbon switches are used when the contactors are attracted Ballast resistors switched on, so that the excitation coils only from part of the flow through the required amperage when tightening and accordingly an overload in the attracted state of the magnetic cores will not experience the coils in continuous operation.

The above-mentioned circuit has, compared to the previously known magnetic circuits, at where the changeover was carried out by a roller, which by a magnet and locking gear is moved, the significant advantage that the complicated control roller is eliminated, the automatic final switch-off by contactors, which also serve as changeover switches, takes place, so no special heavy current end switch is required, also that the

3.5 operational reliability is the greatest conceivable and the motors are switched over directly, so the maneuverability is the greatest conceivable.

In the case of a different switchover, the switching relays used there are designed differently and one of the relays receives two windings, which must be specially coordinated, because the working current of the motors flows through one winding. With the present Switching is the same when using several relays, so that this switchgear for mass production and every motor size suitable is.

The excitation coils are used for higher operating voltages in the present switchover equipped with series resistors. The number of contacts is opposite to known circuits presently reduced to a minimum with intermittent operation.

Claims (1)

Patent claim: Electromagnetic switching device for electric motors, where the armature or the field is switched to change the direction of rotation of the motors and to Motor lead only three long-distance lines, characterized in that of the three Lines, all of which serve as working lines for the engine, two for each each direction of rotation can also be used as control lines for the changeover relay and the relays fed by them always have the same voltage flowing through them as the motor at any given moment receives. · 1 sheet of drawings.