US1476363A

US1476363A - Electromagnetically-actuated apparatus

Info

Publication number: US1476363A
Application number: US626197A
Authority: US
Inventors: Herklotz Max
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1923-03-19
Filing date: 1923-03-19
Publication date: 1923-12-04
Anticipated expiration: 1940-12-04

Description

Dec. 4', 1923. 1,476,363'

M. HERKLOTZ ELECTROMAGNETI CALL! ACTUATED APPARATUS Filed March 19, 1923 A :i v 27;

InVc-antor i Max Her'klobz,

- Hls Attor' ney. I

iiatented Dec. 4, 1923.

UNITED STATES 1,476,363 PATENT OFFICE.

MAX HERKLOTZ, OF BERLIN, GERMANY, ASSIGNOR T GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

ELECTROMAGNETICALLY-AGTUATED APPARATUS.

Application filed March 19, 1923. Serial 110. 628,197.

To aZl whom it may concern:

Be it known that I, MAX HERKLoTz, a citizen of the German Republic, residing at Berlin, Germany, have invented certain new and useful Improvements in Electromag' netically-Actuated Apparatus (for which I have filed an application in Germany, March 2, 1922)., of which the following is a specification.

My invention relates to electromagnetically actuated apparatus which is energized by an electrical condition varying over a very wide range and has for its object the provision of means whereby the range of operation of the apparatus may be increased.

My invention is of particular value in connection with vibratory regulators of the well known Tirrill type. In these regulators one of the vibratory contacts is actuated by a magnet which is energized by the exciter voltage. Since this voltage varies over a wide ran e between no load and full load, considerahle difiiculty has been encountered in designing a relay which will operate satisfactorily over this entire range.

In accordance with my invention I provide suitable devices which cooperate with the electromagnetically actuated apparatus so that the energizatlon of the apparatus varies at a different rate than the electrical condition which energizes the apparatus. In one embodiment of my invention I connect in parallel with the apparatus, a device having a resistance which varies inversely with respect to the variations in the electrical condition energizing said apparatus. Such a device may be a resistor having a. negative temperature coefficient or an electron tube connected so that the resistance of the tube decreases with an increase in the electrical condition energizing the apparatus.

In another embodiment of my invention, I obtain the same result by providing the apparatus with a second exciting winding which opposes the main exciting winding and which is energized in accordance with variations in the electrical condition which energizes the main exciting winding.

My invention will be better understood from the following description taken in connection with the accompanying drawing in which Fig. 1 shows one embodiment of my invention, and Figs. 2 and 3 show modifications of the arrangement shown in Fig. 1.

Referring to Fig. 1, 1 represents a generator, the voltage of which is to be regulated. 2 represents an exciter which is provided with a shunt field winding 3, the excitation of which is controlled by a regulator 4 of the well known Tirrill type comprising a control magnet 5 connected so as to be energized in accordance with the voltage or other electrical condition of the generator 1, and a control magnet 6 connected so as to beenergized in accordance with the voltage of the exciter 2. 7 represents the differentially wound relay magnet of the regulator which has one winding 8 permanently connected across the exciter 2 and another winding 9 aranged to be connected across the eXc-iter 2 when the main contacts 10 of the regulator are in engagement. The

contacts 11 of the dilferential relay magnet 7 control a shunt circuit around a resistance 12 in the shunt field circuit of the exciter.

The arrangement heretofore described is old and well known in the regulator art. As stated above, the.range of such a regulator is limited by the construction of the magnets 6 and 7 which cannot be designed so as to respond to a wide variation in the voltage impressed thereon.

In the embodiment of my invention shown in Fig. 1, I increase the range of the regulator by connecting in parallel with the coil of the magnet 6, a resistor 13 of suitable material such as boron having a negative temperature coefficient. Preferably a resistor 14 which may have a positive temperature coeflicient is connected in series with the coil of the magnet 6 and the resistor 13. In like manner a resistor 15 having a negative temperature coefficient is connected in parallelf'with the coils 8 and 9 of the difierential relay 7 and a resistor 16, which may have a positive temperature coeflicient, is

connected in series with the coils 8 and 9 and the resistor 15.

Since the resistance of the resistors 13 and 15 decreases as the voltage of the exciter 2 increases, a smaller portion of the total currents flowing through the

resistors

14 and 16 flows through the coil of the magnet 6 and through the coils 8 and 9 of the differential relay 7 respectively so that a variation in the voltage of the exciter does not produce a proportional change in the ampere turns of. the magnets 6 and 7.

By means of the resistors 13 and 15, it

is possible to regulate the voltage of the generator over a very much greater range than when they are not used.

Instead of using a resistor of a material having a negative temperature coeflicient,

any other suitable device may be used, the

resistance of which varies inversely with the variable electrical condition to which the particular electrical apparatus is subjected. For example, an electron tube such as a kenotron may be used. Fig. 2'shows a modification of a portion of the system shown in Fig. 1 in which a kenotron 17 is substituted for the resistor 13. The kenotron comprises a plate 18 connected to the positive terminal of the exciter and a filament 19 connected in parallel with the coil of the ma et 6. A resistor 20 is connected in series between the positive terminal of the exciter 2 and the filament so that theplate 18 is more positive than the filament. At low voltages the resistance of the plate circuit of the tube is high so that very little current flows through the tube. As the exciter voltage increases, the temperature of the filament increases and the plate becomes more positivewith. respect to the filament so that a greater portion of the current through the resistor 14 flows through the tube. Consequently 'a variation in the exciter voltage does not produce a proportional variation in the ampere turns of the magnet 6.

In the modification of Fig. 1 shown in Fig. 3, the field winding 3 of the exciter is connected to an auxiliary exciter 25 which is self-excited. The contacts 11 of thedifferentially wound magnet 7 control a short circuit around a resistor .26 in the field circuit of the exciter 25. The magnet 6 of the regulator in this embodiment of my invention is provided with three windings 27, 28 and 29. The winding 27 is connected across the exciter 25. The winding 28 is connected to a source of constant potential such as a pilot generator 30 driven in any suitable manner. As shown, the rotors of the exciter 25 and pilot generator 30 are mounted on the same shaft. The winding 29 is connected across a shunt 31 in the field circuit of the generator 1 so that the excitation of this winding is dependent on the magnitude of the exciting current of the generator 1 which in turn depends upon the voltage of the exciter 25. The windings 27 and 28 are arranged so that they aid each other and oppose winding 29. Preferably windings 28 and 29 are so proportioned that when the generator 1 is running at no load these two windings neutralize each other and only the ampere turns of the winding 27 are effective to operate the magnet. As the load on the generator increases, the excitation of the generator automatically increased by the regulator in the well known manner. Since the excitation of the windage-vanes ing 28 remains constant and the excitation of the winding 29 increases, the resultant ampere turns of the three windings is less than the ampere turns of winding 27. Therefore the action of this device secures the same result as the arrangement shown in Fi s. 1 and 2.

IVhile I have shown and described several modifications of my invention, it is evident that my invention is not limited thereto and I seek to cover in the appended claims all those modifications of my invention that fall within the true spirit and scope of my in--' vention.

What I claim as new and desire to secure by Letters Patent of the United States, 1s:

1. In a regulating system for a dynamo electric machine, an exciter connected to the field winding of said machine, an electromagnet for controlling the excitation of said exciter having a winding so connected that it is energized in accordance with the voltage of said exciter, and means connected so as to be afi'ected by variations in the voltage of the exciter for causing the energization of said electromagnet to vary at a difi'erent rate than the exciter voltage varies.

2.111 a regulating system for a dynamo electric machine an exciter connected to the field winding of said machine, an electromagnet for controlling the excitation of said exciter having a winding so connected that it is energized in accordance with an electrical condition of said exciter, and means so connected and arranged that the current through said means is controlled by the electrical condition of the exciter in accordance with which said winding is energized and the change in current through said means produced by said electrical condition effects a smaller proportional change in the ampere turns of said electromagnet.

3. In a regulating system for a dynamo electric machine, an exciter connected to the field winding of said machine, and an electromagnet for controlling the excitation of said exciter having a winding 'so connected that it is energized in accordance with an electrical condition of said exciter,

nected that it is energized in accordance with an electrical condition of said exciter, a second winding supplied from a constant potential source of current, and a third winding so connected that its excitation varies in accordance with the variations in the electrical condition controlling the excitation of said first mentioned winding, said third winding being wound differentially with respect to the other two windings and arranged so that at no load the combined magnetizing effect of said second and third windings is substantially zero.

5. In a regulating system for a dynamo electric machine, an exciter connected to the field winding of said machine, a second exciter connected to the field winding of said first mentioned exciter, a source of constant potential, and an electromagnet for controlling the excitation of said second exciter having a winding connected so that it is energized in accordance with the v0ltage of said second exciter, a second winding energized in accordance with voltage of said constant potential source, and a third winding connected so as to be energized in accordance with the current supplied to the field Winding of said machine, said third winding being wound differentially with respect to the other two windings and arranged so that at no load the combined magnetizing effect of said second and third windings is substantiall zero.

In witness whereof, have hereunto set my hand this 12th day of February, 1923.

MAX HERKLOTZ.