US1215704A - Automatic electric regulator with stop-charge relay. - Google Patents

Description

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AUTOMATIC ELECTRIC REGULATOR WITH STOP CHARGE RELAY.

7 APPLICATION FILED OCT-9.19M.

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H. H. POWELL.

AUTOMATIC ELECTRIC REGULATOR WITH STOP CHARGE RELAY.

APPLICATION FILED OCT- 9, I912.

Patented Feb. 13, 1917 2 SHEETS-SHEET 2.

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3. TED STATES PATENT OFFICE.

I-IARRY H. POWELL, OF LONDON, ENGLAND, ASSIGNOR, BY MESNE ASSIGNMENTS, TO

U. S. LIGHT 8; HEAT CORPORATION, OF NIAGARA FALLS, NEW YORK, A CORPORA- ILION OF NEW YORK.

AUTOMATIC ELECTRIC REGULATOR WITH STOP-CHARGE RELAY.

Application filed October 9, 1912.

To all whom it may concern:

Be it known that I, I'IARRY H. POWELL, a British subject, residing at 50 Tollington road, Holloway, London, N., England, have invented new and useful Improve ments in Automatic Electric Regulators with Stop-Charge Relays, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawing, forming a part of this specification.

My invention relates to automatic electric regulators adapted particularly for car lighting systems.

The elements which make up a car lighting system are a variable speed generator, a regulator therefor, a storage battery, lamps, a lamp regulator, and an automatic switch for connecting said generator to said storage battery and lamps. These are the main elements, although additional ele ments are often provided. The generator regulator may regulate the generator for constant current, constant voltage or mixed current and voltage regulation. In one of the prior systems the generator is regulated for constant current by a series solenoid which varies the resistance of a shunt circuit around the generator field. My invention relates more particularly to a regulator for a system of this kind, and the object of my invention is to provide such a regulator with a stop charge relay whereby the battery charging current will be discontinued after the battery has been fully charged.

In the accompanying drawings I have illustrated diagrammatically two relays which embody my. invention. The inven tion is, of course, not limited to the forms illustrated but may be embodied in further forms. r v

The view in the drawings are as follows:

Figure l-is a diagram of one form of relay showing the same connected as part of a car lighting system.

Fig. 2 is a diagram of another form of relay connected in a similar system.

Fig. 3 is an elevation partly in section of a mechanical pole changer used in connection with the circuit illustrated in Fig. 1.

Fig. l is a longitudinal sectional elevation thereof.

Specification of Letters Patent.

Patented Feb. 13, 1917.

Serial No. 724,824.

Fig. 5 is a sectional elevation of a modilied circuit closing arrangement such as used 1n connection with the circuit shown in Fig. 2.

The circuit diagram shown in Fig. 1 represents a car lighting system having a variable speed generator, with an armature 1 and shunt field winding 2. The generator supplies the main circuit 3, 4: across which the storage battery 5 and lamps 6 are connected in parallel branches. The automatic switch 7 closes the main "circuit from the generator to the storage battery as hereinafter described.

The generator is regulated for constant current by a solenoid 8 connected in series in the main circuit. when said solenoid is energized it operates to increase the pressure on the variable pressure rheostat 9 the resistance of which is normally a maximum. The rheostat is connected in a shunt circuit around the generator field winding 2 and accordingly when the pressure thereon is increased, the resistance thereof is decreased and the current is diverted around the field winding, thereby decreasing the energization thereof. In this manner the generator is automatically regulated to prevent the current exceeding a predetermined value even when the speed of armature rotation increases to a very high value.

The automatic switch 7 is closed when the generator voltage exceeds the battery voltage, the closing of the switch being elfected by a magnet having voltage responsive coils 10 connected in series with the shunt field winding of the generator and hence connected around the generator terminals. After the switch is closed the series coils 11 of said electro-magnet assist in holding the switch closed, and also act as release'coils, acting difierentially with respect to the shunt coils when the generator voltage drops below that of the battery and the battery begins to discharge through said generator.

An adjustable resistance 12, which may be of any suitable type, is provided to prevent excessive voltage from being impressed on the lamps. This resistance is short circuited when the automatic switch is opened, at which time the battery furnishes all the current to light the lamps. Although the variable resistance 12 is illustrated as a hand operated rheostat, an automatic regulator may, of course, be employed.

Inasmuch as car lighting generators are subject to reversal in the direction of armature rotation, it is necessary to provide a pole changer or other suitable means to reverse the connections between the generator armature and the storage battery when the armature reverses its direction of rotation in order to prevent a reversal in the direction of flow of the battery charging current. A pole changer suitable for this purpose is disclosed in United States Patent No. 751,7a5, February 9, 190st, issued to Morris Moskowitz. In Fig. 3 of the present application drawings I have illustrated enough of the Moskowitz pole changer to indicate the operation thereof and have also illustrated certain additional elements which cooperate with said pole changer to adapt the same for use with the stop charge relay which I have devised.

Referring to said figure, the reference character 13 indicates the generator casing or field frame which is suitably supported by lugs 14: on cross bars 15. The generator armature shaft 16 has mounted thereon a centrifugallv operated latch 17 which is di rectly connected to a weight 18 so that when the armature is rotating above a certain speed the weight 18 tends to fly out by centrifugal force and thereby holds the latch 17 in the retracted position shown in Fig. 3. IVhen the armature begins to rotate, the latch 17 projects radially from the armature shaft 16 a greater distance than shown in said figure and engages a suitable switch tuating member which it moves a short distance in one direction or the other, depending upon the direction of rotation, before said latch is forced inwardly by riding up either of the two inclined walls 19. In cordance with my invention I provide an auxiliary PIXOtGd member 20 which rests on a short plunger 21 carried by the resilient contact member 22, which latter normally tends to engage the stationary contact member 23. As long as the armature is rotating above a certain speed the. contact members 22, 28 are in engagement as shown in Fig. 3, and thereby close a circuit as hereinafter described in connection with Fig. 1. Whenever the armature comes to rest, however, the latch 17 depresses the pivoted member 20 and the plunger 21, thereby opening the circuit at the contacts 22, 23'. The contacts are suitably mounted in a box or receptacle 2-1 which is adapted to be secured directly to the. generator casing 13. It will be seen that in attaching this auxiliary apparatus to a generator already provided with a pole changer, all that is necessary is to drill a few holes and attach the auxiliary equipment. In Fig. 5 I have illustrated a modified arrangement of contacts adapted to operate with the form of stop charge relay illustrated in Fig. 2 hereinafter described more fully. In this modified arrangement the circuit is normally open at the contacts 22, 23 when the generator armature is rotating, but said circuit is closed when the armature comes to rest. Both forms of circuit closers may, of course, be operated by an independent centrifugal device. I have illustrated them as operated by certain elements of the Moskowitz pole changer in order to take advantage of the construction provided therein, for a different purpose. The contact members 22, 23 are indicated in Figs. 1 and 2 by these same reference characters.

The stop charge relay is provided with an electromagnet (or solenoid) having voltwindings connected across the main circuit. When the battery approaches a fully charged condition, the counter electromotive. force rises and the generator voltage rises accordingly. The voltage coils 25 respond to this rise in voltage and attract a pivoted armature 26, thereby closing the auxiliary contacts 27 and 28. The contact 27 closes a circuit through the magnet windings 29 which are connected around the bat tery 5 in a circuit which includes also the contacts 22, 23 operated by the automatic pole changer. It is to be understood, of course, that at the time this circuit is closed by the auxiliary contact 27, said circuit is also closed at the contacts 22, 23 as the generator armature is, of course, rotating, consequently the weight 18 is held out by centrifugal force. Accordingly, the coils 29 are energized by the battery current, and when the current in the voltage coils 25 diminishes, said coils hold the armature 26 in closed position. The attraction of this armature opens the excitation circuit in which the exciting resistance 39 is included. The attraction of the armature also closes a circuit through the contact 28, thereby short-circuiting the variable pressure resistance 9. All current being shunted from the generator field winding, the generator output is eliminated. In this manner the battery charging current is cut oil' and accordingly there is no danger of overcharging said battery. To prevent a dead short circuit across the mains, the fixed resistance 30 is provided.

Inasmuch as the magnet coils 29 are connected around the storage battery, the contacts 27, 28 are held closed and consequently the generator remains inoperative until, in the course of time, its armature slows down below the critical speed, at which time the circuit around the battery is opened at the contacts 22, 23 by a series of kicks imparted by the latch 17, thereby temporarily open-circuiting the coils 29 and permitting the armature 26 to fall back against the contacts 31 and close the excitation circuit. The opening of the circuit at contacts 27 prevents current flowing in coils 29 when contacts 22, 23 regain their normal position and make contact, which they may do immediately, unless the latch 17 happens to come to rest in vertical position. Whenever the generator armature again begins to rotate and the battery again becomes fully charged, the previous cycle of operation is repeated.

In Fig. 2 the operation of the system in general is similar to that just described. WVhen the battery approaches a fully charged condition, the voltage coils 32 respond to the rise in voltage of the generator and the armature 33 is attracted, thereby closing a short circuit around the generator field winding through the contact 34. The

armature 33 is retained locked in the upper position by the pivoted trip rod 35, after the current in coils 32 dies away. The movement of the armature 33 also closes a circuit at the contact 36 arranged in a circuit around the battery, which circuit includes the magnet coil 37 and the contacts 22, 23, the arrangement of the latter corresponding to that shown in Fig. 5. These contacts 22, 23 being separated while the armature is rotated above the critical speed, the circuit to the magnet coils 37 is not completed by the closing of the contact 36. The battery charging current, however, is cut off by the short-circuiting of the generator field winding and accordingly the necessary current for the lamps is furnished by the storage battery after the operation of the stop charge relay. WVhenever the armature slows down below the critical speed, the circuit through the magnet coils 37 is closed by the contacts 22, 23 which are brought into engagement just before the armature ceases to rotate. The upper end of the trip rod 35 is accordingly attracted and unlocks the pivoted armature 33, which thereupon falls to normal position and restores the exciting circuit. All the circuit connections are now restored so that when the generator armature subsequently begins to rotate, the previous cycle of operation will be repeated. The object of providing two gaps in the circuit around the battery, which includes the.magnet coils 37, is to prevent waste of battery current if the generator armature should remain at rest with the pole changer latch in such a position that it continues to keep the contacts 22, 23 in engagement.

It is apparent that the invention is not limited to the details shown and described, as these forms are selected simply for the purpose of illustrating a few embodiments of the invention. Accordingly I do not desire to limit myself to said forms but desire to include suitable equivalent devices and circuit connections wherever covered by the appended claims.

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

1. A regulator for variable speed generators, comprising means for regulating the field strength of the generator, and means for short circuiting said field upon predetermined voltage rise of said generator, said short circuiting means being controlled by auxiliary means responsive to speed of armature rotation.

2. A regulator for variable speed generators, comprising a variable resistance ar ranged in a shunt circuit around the generate-r field, and means for closing a short circuit around said variable resistance, said means including a holding coil connected in circuit across the terminals of a storage battery, said circuit being controlled by the operation of said means and by an additional circuit closer.

3. The combination with a variable speed generator and a storage battery which is charged thereby, of a centrifugally operated circuit closer controlled by the rotation of the generator armature, a voltage relay connected across the generator terminals and arranged to short circuit the generator field upon the attainment of a predetermined voltage, and an auxiliary circuit closed by the operation of said relay, said circuit closer being arranged in said auxiliary circuit.

4. The combination with a variable speed generator and storage battery which is charged thereby, of a centrifugally operated circuit closer controlled by the rotation of the generator armature, a voltage relay connected across the generator terminals and arranged to short circuit the generator field upon the attainment of a predetermined voltage, said relay having auxiliary coils connected in a shunt circuit around said battery, said centrifugally operated circuit closer being also arranged in said shunt circuit and arranged to open said circuit when the generator armature is rotating below the critical speed, and additional contacts in said circuit closed by the operation of said relay, whereby said auxiliary coils hold said relay closed until speed of armature rotation has been reduced nearly to zero.

5. The combination with a variable speed generator and a storage battery which is charged thereby, of a centrifugally operated circuit closer controlled by the rotation of the generator armature, a voltage relay connected across the generator terminals and arranged to short circuit the generator field upon the attainment of a predetermined voltage, said relay having auxiliary coils connected in a shunt circuit around said battery, said centrifugally operated circuit closer being also arranged in said shunt cir cuit and arranged to close said circuit when the generator armature is rotating above the critical speed, and additional contacts in said circuit closed by the operation of said relay, whereby said auxiliary coils hold said relay closed until speed of armature rotation has been reduced nearly to zero at which time said shunt circuit is opened by the operation of said centrifugally operated circuit closer, thereby permitting the relay to fall open.

6. A stop charge relay for an automatic electric regulator, comprising a lifting coil, a holding coil and a movable armature controlled by the energization of said coils, the circuit of said holding coil being closed through contacts controlled by said movable armature, and an additional circuit also controlled by said armature.

7. In a car lighting system,- a variable speed generator having a shunt field winding, a variable resistance for varying the energization of said field winding, and a relay which responds to the predetermined voltage increase of the generator, said relay comprising a lifting coil, a holding coil and a movable armature controlled by the energization of said coils, the circuit of said holding coil being closed through contacts controlled by said movable armature, and an additional circuit also controlled by said armature.

8. In a car lighting system, a variable speed generator having a shunt field winding, a variableresistance for varying the energization 01 said field winding, and a relay which responds to the predetermined voltage increase of the generator, said relay comprising a lifting coil, a holding coil and a movable armature controlled by the energization of said coils, the circuit of said holding coil being closed through contacts controlled by said movable armature, and a short circuit around said generator field winding also controlled by said movable armature.

9. A car lighting system comprising a variable speed generator, having a shuntfield winding, a variable resistance connected in a shunt circuit around said field winding, said resistance being normally a maximum, whereby the energization of said field winding is normally a maximum, a current responsive coil in the generator circuit adapted to decrease said resistance as the generator current tends to increase, thereby regulating the generator for constant current, a voltage responsive relay connected around the generator terminals and adapted upon predetermined voltage rise of the generator to close a short circuit around said generator field winding, and means for maintaining said short circuit closed after said generator voltage drops below the point necessary to cause the operation of said relay, and additional means permitting the restoration of said relay when the generator comes to rest.

10. A car lighting system comprising a variable speed generator, having a shunt field winding, a variable resistance connected in a shunt circuit around said field winding, said resistance being normally a maximum, whereby the energization of said field winding is normally a maximum, a current responsive coil in the generator circuit adapted to decrease said resistance as the generator current tends to increase, thereby regulating the generator for constant current, a voltage responsive relay connected around the generator terminals and adapted upon predetermined voltage rise of the generator to close a short circuit around said generator field winding, and means for maintaining said short circuit closed after said generator voltage drops below the point necessary to cause the operation of said relay, and additional means permitting the restoration of said relay when the generator comes to rest, said means including centrifugallyoperated circuit closing contacts.

11. A car lighting system comprising a variable speed generator and a shunt field winding, a storage battery connected across the external circuit of the generator, a regulator for maintaining the generator current within' predetermined limits, a stop charge relay for decreasing the generator current after the storage battery has become fully charged, and an excitation circuit in which said shunt field winding is included also controlled by said relay.

12'. A car lighting system comprising a variable speed and shunt field generator, a main circuit supplied thereby, a storage battery and translating devices connected across said main circuit, a generator regulater for maintaining the generator current within predetermined limits, a stop charge relay connected across the generator terminals, said relay being adapted to close a shunt circuit around the generator field winding and thereby cut off the generator charging current after the battery has become fully charged, and means for maintaining the shunt circuit around said field winding until the generator armature comes nearly to rest.

13. In a car lighting system, a variable speed generator, a storage battery to be charged thereby, means depending on the state of battery charge to reduce the generator output when the battery is fully charged, and means depending on the speed of the generator armature to render said generator capable of delivering its normal output.

14, In a car lighting system, a variable speed generator, a storage battery to be charged thereby, a stop charge device for reducing the normal generator output when the battery becomes fully charged, and means for rendering the generator capable of delivering its normal output, said means being operated by the slowing down of the generator below a predetermined speed.

15. In combination, a variable speed generator, a regulator -tor reducing the generator output under predetermined electrical conditions, and mechanical means for ren dering the generator capable of delivering its normal output.

16. In combination, a variable speed generator, a regulator for causing said generator to deliver less than its normal output, and a centrifugal device for restoring said generator to normal condition whenever its armature speed reduces below a predetermined point.

17. In combination, a variable speed shunt wound generator, electrical means for diverting current from the shunt field winding under predetermined conditions, and mechanical means for restoring said electrical means to normal condition.

18. In combination, a variable speed shunt Wound generator, electrical means for diverting current from the shunt field winding under predetermined conditions, and mechanical means for restoring said electrical means to normal condition whenever the generator speed reduces below a predetermined point.

19. In combination, a variable speed shunt wound generator, electrical means for diverting current from the field winding, a centrifugal switch operated by the generator armature, and means whereby said centrifugal switch restores said electrical means to normal condition whenever the generator speed reduces below a predetermined point.

20. In combination, a car lighting gen erator subject to reversals in the direction of armature rotation, a centrifugally operated pole changing switch associated with said generator and controlled by the speed of armature rotation, auxiliary contacts controlled by said pole changing switch, and an inclosing receptacle for said contacts, said receptacle being detachably secured to said pole changing switch whereby it may be attached thereto or removed therefrom without interfering with the operation of said pole changing switch.

In witness whereof, I have hereunto subscribed my name in the presence of two witnesses.

HARRY H. POWELL.

Witnesses ALEXANDER AUBREY BLAKER,

O. J. WORTH.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. G.

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