US2424826A - Sequential electric switching system - Google Patents

Description

July 29, 1947. F. R. JACKSON, JR

SEQUENTIAL ELECTRIC SWITCHING SYSTEM Filed June 20, 1945 Inventor: Frederick R. Jackson Jr,

Patented July 29, 1947 SEQUENTIAL ELECTRIC SWITCHING SYSTEM Frederick R. Jackson, Jr., Pittsiield, Mutt, asaignor to General Electric Company, a corporation of New York Application June 20, 1945, Serial No. 600,602

My invention relates to sequence control arrangements and particularly to an arrangement for sequentially controlling two switches so that they are alternately closed for a predetermined time interval with a predetermined time interval between successive switch closures.

One object of my invention is to provide an improved arrangement of parts whereby the time interval each switch is closed and the time interval between successive switch closures may .be readily adjusted independentlyof each other.

My invention will be better understood from the following description when taken in connection with the accom anying drawing, the single figure of which diagrammatically illustrates an embodiment of my invention in connection with an arrangement for alternately connecting two electric circuits to a third electric circuit, and the scope of my invention will be pointed out in the appended claims,

Referring to the drawing, I and 2 represent two electric circuits which are arranged to be connected to a third electric circuit I by the switches 4 and I, respectively. In accordance with my invention, I provide a control arrangement for the switches 4 and I so that the circuit I is alternately connected to and disconnected from the circuits I and 2 including a time relay I which controls the length of time each switch is maintained in its closed position and a time relay 1 which controls the length of time between successive switch closures. As shown, the time relay I is arranged to be energized when either the switch 4 or the switch I is closed, and the time relay I is arranged to be energized when both oi. the switches 4 and I are open at the same time. I is an auxiliary relay which, when deenergized, is arranged to be energized to effect the closing of the switch 4 in response to the time relay I completing its timing operation. I is another auxiliary relay which is arranged to be energized to eflect the opening oi! the switch 4 in response to the time relay I completing its timing operation while the switch 4 is closed. The auxiliary relays I and I are arranged to complete locking circuits for themselves. The time relay I, when it completes its timing operation in response to the opening of the switch 4, is arranged to eflect the closing of the switch I. and the time relay I, when it completes its timing operation in response to the closing of the switch I, is arranged to eflect the opening or the switch I and the opening or the locking circuits oi the auxiliary relays I and I so that the next completion of the timing relay 1 in response to the opening 01 the switch I initiates 5 Claims. (Cl. -075) 2 another cycle of operation of the switches 4 and I. A control switch II is provided which, when closed, renders the sequence control arrangement operative.

The operation of the control arrangement is as follows: When the control switch I0 is closed, an energizing circuit is completed for the time relay 1 through the contacts or the control switch III, the contacts I I of the open switch 4 and the contacts I2 oi the open switch I. When the time relay I completes its timing operation and closes its contacts II, an energizing circuit is completed for the auxiliary relay I through the contacts of the control switch It) and the contacts II of the auxiliary relay I. The closing of the contacts II of the auxiliary relay I completes a locking circuit tor the winding of relay I through the contacts o! the control switch II and the parallelconnected contacts II and II of the time relay I and of the switch I, respectively. The closing of the contacts II of the auxiliary relay I completes an energizing circuit for the operating winding of the switch 4 through the contacts II of the auxiliary relay 9, the parallel-connected contacts II and ll of the time relay I and oi! the switch I, respectively, the contacts II of the auxiliary relay I and the contacts 01' the control switch III. The closing of the main contacts oi! the switch I connects the electric circuit I to the electric circuit I, and the opening of the contacts IIoi the switch 4 interrupts the energizing circuit or the time relay 1. The closing of the auxiliary contacts 20 of the switch 4' completes an energizing circuit for the time relay I through the contacts of the control switch II. The opening of the contacts II of the time relay 1 does not effect the deenergization of the windings of the auxiliary relay I and the switch 4 at this time because the circuits of these windings are now completed through the parallel-connected contacts II and I1 0! the time relay I and of the switch I, respectively, and the contacts II of the auxiliary relay 8.

When the time relay I completes its timing operation and closes its contacts 2I, an energizing circuit is completed for the auxiliary relay 9 through the contacts ll of the switch I, the contacts II oi the auxiliary relay 8 and the contacts of the control switch II. The closing of the contacts 22 of the auxiliary relay 9 completes a shunt circuit around the contacts 2L0! the time relay I so that a locking circuit is completed for the auxiliary relay 9 to maintain the relay energized after the time relay I subsequently opens its contacts 2i. The opening of the contacts II 01' the auxiliary relay I interrupts the heretofore described energizing circuit for the operating winding of the switch 4 so that the electric circuit I is disconnected from the electric circuit 3. The openin of the contacts 20 of the switch I interrupts the energizing circuit for the time relay I, and the closing of the contacts I l of the switch 4 re-establishes the heretofore described energizing circuit for the time relay 1.

When the time relay 1 completes its timing operation and closes its contacts it while both of the auxiliary relays 8 and 5 are energized, an energizing circuit for the operating winding oi the switch 5 is completed through the contacts of the control switch l and the contacts 23 01 the energized auxiliary relay 9. The closing or the main contacts of the switch connects the electric circuit 2 to the electric circuit 3. The closing of the auxiliary contacts 24 of the switch 5 completes a locking circuit for the operating winding of the switch 5 through the contacts ll of the time relay ii, the contacts [5 of the energized auxiliary relay 8 and the contacts of the control switch Ill. The opening of the contacts [2 of the switch -5 interrupts the energizing circuit or the time relay 1, and the closing of the contacts 25 0f the'switch 5 completes an energizing circuit for the time relay 6 through the contacts of the control switch ill.

When the time relay 6 completes its timing operation while the switch .5 is closed, the opening of the contacts H5 or the relay 6 interrupts the heretofore described locking circuits {or the auxiliary relays 8 and 8 and for the operating winding of the switch 5 so that the electric circuit 2 is disconnected from the electric circuit 3. The opening of the auxiliary contacts 25 or the switch 5 interrupts the energizing circuit for the time relay 8, and the closing of the auxiliary contacts (2 of the switch 5 re-establishes the energizing circuit for the time relay 1 which, after being energized for a predetermined time, initiates another closing of the switch 4 in the manner heretofore described.

It will be observed that in the arrangement shown in the drawing the length of time the switches 4 and '5 are closed may be adjusted by varying the operating time of the time relay 6 and that the length of time the two switches remain open may be adjusted by varying the operating time of the time relay 1, and any adjustment in the operating time of either time relay in no way affects the operating time of the other.

While I have, in accordance with the patent statutes, shown and described my invention as applied to a particular system and as embodying various devices diagrammatically indicated, changes and modifications will be obvious to those skilled in the art, and I therefore aim in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of my invention.

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

1. In combination, two switches, a timing device, means for effecting a timing operation of said timing device in response to both of said switches being simultaneously open, a second tim ing device, means for efl'ecting a timing operation of said second timing device in response to either of said switches being closed, and means jointly controlled by said timing devices for effecting the alternate closing of said switches in response to successive timing operations of said first mentioned timing device and 01- effecting the alternate opening of said switches in response 4 to successive timing operations or said second timing device.

2. In-combination, two switches, a timing device. means for eilecting a timing operation of said timing device in response to both of said switches being simultaneously open, a second timing device, means for eflecting a timing operation of said second timing device in response to either of said switches being closed. means for effecting the closing oi a predetermined one 0! said switches in response to said first mentioned timing device completing its timing operation, means for eflecting the opening of said predetermined one of said switches in response to said second timing device completing its timing operation while said predetermined one or said switches is closed, means for effecting the closing or the other of said switches in response to said first mentioned timing device completing its timing operation when said one of said switches is opened by said second timing device, and means for efl'ecting the opening of said other or said switches in response to said second timing device completing its timing operation when said other 01' said switches is closed.

3. In combination, two switches, a timing device, means ior effecting a timing operation of said timing device in response to both or said switches being simultaneously open, a second timing device, means for effecting a timing operation of said second timing device in response to either or said switches being closed, an auxiliary relay, means for effecting the energization of and the completion of a locking circuit for said auxiliary relay and th closing of a, predetermined one or said switches in response to said first mentioned timing device completing its timing operation while said auxiliary relay is deenergized, means for effecting the opening 01' said predetermined one of said switches in response to said second timing device completing its timing operation while said predetermined one of said switches is closed, means for effecting the closing 01' the other of said switches in response to said first mentioned timing device completing its timing operation when said one of said switches is opened by said second timing device, and means for eflecting the opening or said other 0! said switches and of said locking circuit in response to said second timing device completing its timing operation when said other of said switches is closed.

4. In combination, two switches, a timing device, means for effecting a timing operation or said timing device in response to both 01' said switches being simultaneously open, a second timing device, means for eflecting a timing operation or said second timing device in response to either or said switches being closed, two auxiliary relays, means for eiiecting the energization of and the completion or a locking circuit for one 01' said auxiliary relays and the closing oi a predetermined one 01' said switches in response to one or said timing devices completing its timing operation while both of said auxiliary relays are deenergized, means for eii'ecting the energization of and the completion of a locking circuit for the other or said auxiliary relays and the opening or said predetermined one of said switches in response to said second timing device completing its timing operation while said one of said auxiliary relays is energized, means for effecting the closing of the other or said switches in response to said one of said timing devices completing its timing operation while both of said auxiliary relays are energized, and means for eii'ecting the opening of said other of said switches and the opening of all of said locking circuits in response to said second timing device completing its timing operation while both of said auxiliary relays are energized.

5. In combination, two switches, a time relay, means controlled by said switches for efiectlng a timing operation of said relay when both of said switches are open, a second time relay, means controlled by said switches for eflecting a timing operation of said second time relay when either of said switches is closed, an auxiliary relay, a secondary auxiliary relay, means controlled by said first mentioned time relay and said second auxiliary relay for effecting the energization of said first mentioned auxiliary relay in response to said first mentioned time relay completing its timing operation when said second auxiliary relay is deenergized, a locking circuit for said first mentioned auxiliary relay, means controlled by said auxiliary relays for eflecting the closing of one of said switches when said first mentioned auxiliary relay is energized and said second auxiliary relay is deenergized, means controlled by said second time relay and said auxiliary relays for effecting the energization of said second auxiliary relay in response to said second time relay completing its timing operation when 6 said first mentioned auxiliary relay is energized and said second auxiliary relay is deenergized, a locking circuit for said second auxiliary relay, means responsive to the energization of said second auxiliary relay for effecting the opening of said one of said switches, means controlled by said second auxiliary relay and said first mentioned time relay for effecting the closing of said other switch in response to said first mentioned time relay completing its timing operation while said second auxiliary relay is energized, and means controlled by said second time relay for efiecting the opening of said other switch and said locking circuits in response to said second time relay completing its timing operation when said other switch is closed.

FREDERICK R. JACKSON, JR.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,140,601 Serriere Dec. 20, 1938 2,370,727 Holden Mar. 6, 1945

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