US1508359A - System of selective control - Google Patents

Description

Se t. 9 1924. 1,508,359

E R. CARICHOFF SYSTEM OF. SELECTIVE CONTROL Filed Jan. 4, 1922 Inventor-fif- Eugene CaPicho-F His fl-h-torne g.

Patented Sept 9, 1924.

\ ,508,35- T FIcE,

EUGENE R. canrcrrorr, or sorrnunoranr, NEW Year, A'SSIGNOR' 'r'o GENERAL ELECTRIC ooMrAuY, A CORPORATION or NEW YORK.

SYSTEM OF SELECTIVE CONTROL.

Application filed. January '1 0 all whom it may concern:

Be it known that I, EUGENE R. CARL errors, a citizen of the United States, residing at Schenectady, in the county of Sche- My invention relates to an improved se lective control system whereby any desired portion of a plurality of separate paths from the supply conductor maybe selected and established at will. The invention has a particular application in the selective control of the direction of operation of an electric vehicle from a point remote from the vehicle, although the invention is not necessarily limited to such use. I

One of the-objects of the invention is to provide an arrangement whereby afterthe particular portion of the paths for the current from a single supply conductor has been selected and established, the uninten- 'tional establishment of another portion of the paths is prevented.

My invention is particularly improvements in the system of selective control, for which John Eaton filed an application for patent, Serial No. 526,983, filed January 4, 1922, which is assigned to the same assignee as this invention.

In general, the system of selective control, disclosed and claimed in the said Eaton application, comprises elect'ro-responsive switch mechanism energized from the supply conductor for establishing the particular portion of the paths for the current from the conductor, and the selective operation of the electro-responsive switch mechanism is controlled. by means of a selector relay which is controlled responsively to the potential of the supply conductor. The potential of the supply conductor is controlled by means of a controller located at a remote point. While the Eaton sys% tem is entirely operative and practical for the ordinary conditions encountered in the service for which the system is intended, diificulties are encountered due to unusual or certain special conditions. Thus, in case the full potential of the supply conductor is rendered ineffective to control the selector relay, due for instance, to the presence of a high resistance condition such as sleet or dirt on the supply conductor, dirt on the directed to 4, 1922. SerialNo. 526,885.

track return when the systemis used for the control of an electric vehicle, or the trolley of the vehicle temporarily leaving the trolley wire, the selector relay may not function exactly as intended, and, may .select one portion of the paths for thecur: rent when it is desired that another portion be selected. Anothercondition to'bepro-a vided againstis encountered, when the path established from the, 'supplyconductor is opened, either intentionally or unintentionally. In such a case, it may happen that a gradually decreasing current from the supply conductor may :cause the unintentional operation of the selector relay, and in case,,for example, the control system be used to govern the direction of operation of an electric vehicle, the vehicle may be unintentionally reversed at such a time. 7 My invention provides improved means whereby this unintentional establishment of any one of the particular portions of the paths from the conductor is prevented.

In carrying my invention into 'efi ect in one form, I have provided electromagnetic means-under the control ofthe potential of the supply conductor for preventingthe operation of the selector relay after it has operated to select aparticular path for the current and so effectively lock the relay in the position, to which it has been operated and thereby prevent any unintentional operation of the same.

For a better understanding of the invention, reference is had to the accompanying drawing wherein I have illustrated an embodiment of my invention in the selective control for an electric vehicle from a point remote from the vehicle. Referring to the drawing, the electric vehicle has not been shown since that would add nothing to an understanding'of the invention; The electric motor for driving the vehicle has an armature 10, a comniutating'field 11 and a series field 12. The direction of operation of this motor and the vehicle driven thereby is controlled by means of the electro-respon-' sive reversing switch mechanism which comprises the double-p0le electromagnetically operated switch or contactor'13 for the forward direction of operation and the double-pole contactor 14 for the reverse direction of operation. These direction contactors are suitably interlocked by means of the pivoted locking bar 15 so that only one contactor may close at a time. The direction contactors 13 and 1 1 are provided for establishing separate paths for the current from the single supply conductor 16 with which the trolley 17 ot the vehicle is nor mally in engagement.

The selective operation of the direction contactors 13 and 1 is under the control of the selective relay 18. This relay comprises a single switch member 19 Which is under the joint control of the two series lockouttype electromagnets 20 and 21. These electromagnets are each of the well-known type which is magnetically held in a biased poition when the current in the winding of the electromagnet is above a predetermined value and which causes a movable member of the electromagnet to operate to another position and be magnetically hold therein when the current in the winding of the electromagnet is below a predetermined value. The relays are diagrammatically illustrated as of the type fully described in Letters Patent to Harry R. Caniield No. 1,3l4,260, dated June 22.. 1920, although my invention is notnecessarily limited to the particular type of series relay disclosed in this application and covered broadly by the said Canfield patent. The electromagnet 20 is provided with a movable magnetic member or plunger 22 which is adapted to be brought into engagement with the switch member 19 to tilt the same, and the electromagnet 21 is provided with a plunger for tilting the switch member 19 in the opposite direction. The electromagnet 20 is provided for selecting the forward direction o'l' operation and the electromagnet 21 is provided for selecting the reverse direction of vehicle operation.

The selector relay 18 is controlled by means of a reversing controller at 2% which is also provided with means for controlling the acceleration and the speed of operation of the motor vehicle after the selected path .tor the current has been established by the operation of either one or the other of the direction contactors 13 and. l-il. The controller 2 l is adapted to control the compaia tively high resistance resistors and 26 tor controlling the selective operation ot' the relay 18. The accelerating and speed varying resistor 2? is adapted to be short circuited step by step by means of suit le contact segments on the controller for b= forward and reverse operation. The 1 section of this resistor 2'? is controlled by the series eontactor 28 which is provided for the purpose of insuring that at a portion of the resistor 27 will be included. in the motor armature circuit until the current taken by the motor has dropped to a predetermined value. The series lockout type c'ontactor 28 is diagrammatically illustrated as of the type fully disclosed in Letters Patneoaeee ent to Edwin J, Murphy No. 1,352,307, dated September 7, 1920.

The unintentional operation of the selec tor relay is prevented by electro-responsive means comprising the electromagnet 29, the winding 01 which is permanently connected to the supply conductor 16 through the trolley 17. This electromagnet is provided with a magnetic movable member 30 which serves as a locking detent tor the pivoted switch member 19. The magnetic locking member 30 is normally biased out of engagement with the arm secured to the switch member 19, and is arranged so that when the electromagnet is energized, the locking member makes engagement with this arm 31 to prevent the operation of the switch 19 to its other position until after the electromagnet 29 is deenergizec. rlrlthough the general controlv system is disclosed and claimed broadly in the aforesaid Eaton ap plication the particular form of selector relay which I have selected for the purpose of illustrating my invention and the connection of this relay in a selective system of control is disclosed and claimed in an application tor patent filed by Charles Coir nely, Serial No. 54l(5,'?76, filed lilarch 25, 1922, and assigned to the same assignee as this invention.

As thus constructed and arranged, the op eration oi my invention is as follows: It is believed that an understanding of the invention will be more readily had by indicating generally a particular system in which the various devices are intended to operate at selected voltages or current values, and l shall therefore describe my invention in this manner, but would have it understood that my invention is not necessarily limited to the following relation of the various parts, but that the particular example is given for the sole purpose of obtaining a quick understanding of the invention. Let it be as sumed that the voltage of the source of supply indicated at is volts and that the operating electromagnets of the direction contactors 18 and 1 1 will be energized to close at any voltage above volts, but not at any lower voltage. Assui'ne that it is desired that the motor vehicle operate in the forward direction. The switch member 19 of the selector relay 18 is in the proper tion for this *ClllCCiiOD oiioperation, so that by moving the reversing controller 24 from its oil position toward the right to its first operative position the series windings or the relays 20 and 21 will be connected from the source of supply through a circuit in cluding the high resis "108 selector resistor 26, the accelerating resistance 2?, supply conductor 16, trolley 17, throughthe windings of the electromagnets 20 and 21, the armature 10 of the electric motor and commutating .field 11 to the ground return,

which is indicated as the return conductor for the system. The value of the resistor 26 will be such that the potential of the supply conductor 16 will be reduced to such a value that substantially 2 amperes will flow through the windings of the relays. This value of current will cause the operation of the plunger 22 of the electromagnet 20, but the plunger 23 of the electromagnet 21 will be magnetically held in its biased position. The operation of the plunger 22 produces no efiect on the switch member 19, for the reason that it is already in the proper position for selecting the forward direction of operation. The voltage of the supply conductor 16 will be belew 230 volts, the value at which the direction contactor 13 will be energized to close, and this con'tactor will not be energized to close until the controller 24:

is advanced to its second operative position, at which the resistor 26 will be excluded from the circuit. When this happens, the potential of the supply conductor 16 will be increased above 230 volts and the direction contactor will be energized to close through the switch member 19 ot' the selector relay. When the contactor 13 closes, one path for the motor current is closed from the plus side of the source of supply 32, through the accelerating resistor 27, supply conductor 16, trolley 17 upper contacts of the contactor 13, through the series field 12 of the motor, through the series holding winding 33 associated with the lower contacts of the contactor 13, lower contacts of contactor 13, through the motor armature 10 and commutating field 11 to the ground return. The locking electromagnet 29 for the selector relay will be substantially simultaneously energized to attract its locking member 30 with the closing of the direction contactor 13. The winding of the locking electromagnet 29 and the magnetic circuits of this electromagnet are designed so that the locking member 30 will not be attracted into locking engagement with the arm' 31 until a voltage is applied to the winding which is above the voltage at which the re lays 20 and 21 will operate so as not to interfere with the operation of the relays under normal conditions, but after the looking member 30 is operated to the attracted position it will be maintained in the at tracted position even though the current through the winding of the electromagnet drops to a very lowvalue.

In order to accelerate the electric motor, the controller 24 is advanced toward the right through its successive operating positions until the final position has been reached at which the winding of the series lock-out type contactor 28 is included in circuit. When the current taken by the motor has dropped to a predetermined value this series contactor will close and short circuit the final section of the resistor 27, thereby connecting the motor directly across the source of supply. If for any reason the ei fective potential applied to the motor and applied to maintain the direction contactor 13 closed should drop below the value at which the direction contactor 13 will open, the windings of the electromagnets of the selector relay are included in series with the motor armature, so that the current through these windings may drop to such a value that the plunger 23 of the electromagnet 21 will operate to endeavor to throw the switch member 19 to its opposite position. The locking electromagnet 29 is provided for taking care oi conditions of this general nature. If, for example, the trolley 17 should temporarily leave the conductor 16 and draw an arc, the direction cont-actor 13 may open and in this case the relay windings are included in series with the are, so that the relay may tend to select for the other direction of operation in such a condition. Another condition provided against by the locking electromagnet 29 is the drawing of an arc at the final segment of the con.- troller 24L when the controller is returned to its of? position. The establishment of such an are at the controller for asmall interval of time may cause the selector relay to attempt to operate and establish the connections for the opposite direction of rotation. Another condition provided against by the provision of the locking electromagnet is the presence of sleet or dirt on the trolley wire 16 or some high resistance condition on the track return for the vehicle. 3 i

It will be understood that in case it is desired to operate the motor vehicle in the reversedirection the controller 24 is first returned to its off position. The direction contactor 13 will thereupon be deenergized and open, and the winding of the locking electromagnet- 29 will be deenergized so as to release the locking member 30. In order to reverse the direction of motor operation, the controller 24 is moved from the 01f position toward the left to its first operative or selective position. Both of the high re sistance resistors 25 and 26 are thereupon included in the circuit of the windings of the electromagnets 20 and 21 of the selector relay 18. The two resistors 25 and 26 will limit the value of current through the relay windings to 1 ampere, tor example. With this value or current, the electromagnet 20 will not be sufficiently energized to operate its plunger 22, but the electromagnet 21 will be sufliciently energized to operate its plunger 23 and thereby tilt the switch memof current through the winding of the looking electromagnet 29 will not be suiiicient to cause the locking electromagnet to operate. When the controller 2% is moved to its second operative position to the left, substantially full potential is applied to the supply conductor 16, and the direction contactor id will be energized to close to establish the circuit for the motor from the supply conductor and the locking electromagne-t 29 will be energized. to att ct the locking member 30 to prevent further unintentional opera tion of the selector relay. The path for the motor current will now be established from the source of suppl through the acceleratif resistor 27, the supply conductor 16, trolley ll} lower contacts of the direction c :-ntactor 314i, through the series holding coil through the iirmtor field 2.2 in a direction opposite to that established by the closing of the direction contactor 13, through the upper contacts oi? the direction contactor 14, motor armature l0 and eommut-ating field ll. to the ground return. The acceleration of the motor will be governed by short circuiting step by step the accelerating resistor 27. The locking electromagnet 29 will now prevent the unintentional operation of the selector relay in the same manner that previously explained.

In accordance with the provisions of the patent statutes, I have described the principle of operation oi? my invention, together with the apparatus which I now consider to represent the best embodiment thereof, but I desire to have it understood that the apparatus shown is only illustrative and that the invention may be carried out by other means.

lVhat l claim as new and desire to secure by letters Patent of the United States, is

The combination in a selective system of control of a supply conductor, electro responsive switch mechanism for establishing a selected portion of a plurality of separate paths from the said conductor, an electro-responsive relay connected to the said conductor and operated responsively to the potential of the conductor for controlling the energization of the said switch .mechaitiism to select the portion of the said paths "from the said conductor to be established, and electro responsive means energized responsively to the potential of the said conductor for locking the said relay from further unintentional operation after the desired portion of the said paths has been selected.

2. The combination in a selective system of control of a supply conductor, electroresponsive switch mechanism for establishing a selected portion of a plurality of separate paths from the said conductor, an electro-responsive relay connected to the said conductor and operated responsively to the 3. The combination in a selective system oi control of a supply conductor, a plurality of separate paths from said conductor, electroresponsive switch mechanism for establishing a selected portion of said paths, an electro-responsive relay connected to the said conductor and operated responsively to the potential ot' the conductor for controlling the energization of the said switch mechanism to select the portion of the said paths from the said conductor to be established, and an electron'iagnetic lock energized from the said conductor for preventing turther unintentional operation oi the said relay utter the desired portion oi? the said paths l'xas been selected the said lock arranged to operate at higher value of potential than. the operating potential of said relay and maiiuiain its locking efi ect at a lower value of potential than the operating potential of said relay.

Z The combination in a selective system ot' a control of a supply conductor, electro responsive switch mechanism for establishing a selected portion of a plurality of separate paths from the said conductor a relay connected to the said conductor for controlling the energization of the said switch mechanism to select the desired portion of the said paths to be established, electro magnetic operating means for the said. relay arranged to operate within one range of values of the potential of said conductor and be magnetically held "from operating at higher values of the potential of the said conductor, and electro-responsive means for locking the said relay to preventthe unintentional operation of the same, the said locking means arranged to operate at a higher potential of the supply conductor than the said operating range of said relay and to n- "intain its locking effect at a poten-- tial of the supply conductor below the said operating range of potential oi the said relay.

A reversing control system for electric motors comprising a motor supply conductor electro-responsive reversing switch mechanism, a selector relay operated responsively to the potential of the supply conductor for controlling the said switch mechanism, a reversing controller for controlling the potential of the supply conductor to con trol the operation of the said relay, and an.

"too

able in the other direction to connect the supply conductor to the source of supply with the said resistor excluded, electroresponsive motor reversing switch mechanism, an electro-responsive selector relay 7 operated responsively to the inclusionand GXClUSlOD of the said reslstor 1n clrcult With the said supply conductor for controlling v i the said reversing switch mechanism, and a;

normally released electromegnetically con trolled lock energized from the said supply conductor for preventing the operation of the said relay except under the control of the said controller.

In Witness whereof, I have hereunto set my hand this 28th day of December, 1921 EUGENE R. CARIGHOFF

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