US2216597A

US2216597A - Time delay control system

Info

Publication number: US2216597A
Application number: US185180A
Authority: US
Inventors: Minneci Salvatore
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1938-01-15
Filing date: 1938-01-15
Publication date: 1940-10-01
Anticipated expiration: 1957-10-01

Description

Oct. 1, 1940. s. MINNECl TIME DELAY CONTROL SYSTEM Filed Jan. 15, 1938 F I i I .AMU zum Inventor salvatore Minneci,

by is :J/MAM ttorney,

Patented Oct. 1, 1940 UNITED STATES TIME DELAY CONTROL SYSTEM Salvatore Minneci, Pittsfield, Mass, assignor to General Electric Company, a corporation of New York Application January 15, 1938, Serial No. 185,180

6 Claims.

This invention relates to time delay control systems, and more particularly to improvements in time delay control systems for automatic regulators.

' Many regulated quantities contain continual relatively small fluctuations which it is unnecessary for the regulator to correct and which would cause excessive operation of the regulator if it did attempt their correction. Consequently, time delay means are often included in the control of automatic regulators, so that they, will only respond when the regulated condition or quantity deviates from its normal value for a predetermined length of time. a In accordance with this invention a novel time delay system is employed in which the time delay is positive and is independent of changes in ambient temperature, circuit voltage and various other quantities which might efiect the duration of the time interval.

An object of the invention is to provide a new and improved time delay control system.

Another object of the invention is to provide a rugged and simple reversible motor-operated adjustable time delay contactor.

The invention will be better understood from the following description taken in connection with the accompanying drawing and its scope will be pointed out in the appended claims.

Referring now to the single figure of the accompanying drawing, which is a so-called exploded perspective view of a reversible motor-operated adjustable time delay contactor embodying my invention, there is shown therein a reversible motor I. This motor may be of any suitable type and is shown by way of example as consisting of an element 2 for producing forward rotation of the motor and an element 3 for producing reverse rotation of the motor. These elements may correspond to those used in the small self-starting single phase synchronous motors commonly employed to drive electric clocks. motor I is a speed reducing means 4 of any suitable type such as speed reducing gearing. Driven by the speed reduction gearing 4 is a crank shaft 5 rigidly fastened to which is crank 6 carrying a crank pin 1. Loosely mounted on the crank shaft 5 is a gear 8 which is arranged to be driven by the crank 6 by means of a detent 3 carried thereby. The detent is urged into its locking position by means of a spring I0 and is fastened to a knob II which when pulled toward the left,

releases the engagement of the gear 3 and he detent 9 and, thus, permits an adjustment to be made between the angular relation of the crank Driven by the 6 and the gear 8. Carried by'the gear 8is a pin I2.

Arranged for cooperation-with the pin 1 is a lever I3 fastened to a shaft I4 which carries a contact operating member I5 for controlling the opening and closing of a normally open set of contacts I6. Arranged for cooperation with the pin I2 is another lever II which is loosely mounted on the shaft I4 and which is rigidly fastened to a. contact operating member I8 for controlling the operation of a normally open set of contacts l9 and a normally closed set of contacts 20. A coil spring 2| serves to bias the contacts I6 and 20 to their closed positions and to bias the contacts I9 to their open position.

Carried by the gear 8 is a time scale 22 which is calibrated directly in units of time delay, so that, for example, the numbers thereon may be taken to represent seconds of time delay. For cooperation with this scale there is a pointer 23 carried by the crank 6. and the scale directly opposite this pointer is viewed through a window 24 in the crank 6.

The time delay contactor has a normal or reset position and it is in this position that the parts have been illustrated. This position is also indicated by the registration of a fixed reference mark 25 and a pointer 26 on the crank 8.

The motor elements 2 and 3 are selectively energized from a supply circuit 21 by means of a suitable circuit control switch 28. When this switch is closed in its uppermost position an energizing circuit for the forward motor element 2 is completed through the time delay opening contacts 20 and when the switch is closed in its lowermost position an energizing circuit for the reversing motor element 3 is established through the run back contacts I6.

The operation is such that when the forward direction motor element 2 is energized, the crank 6 will rotate in a counter-clockwise direction. Substantially the instant that it starts to turn in this direction the pin I will allow the lever I3 and the contact-operating member I5 to turn sufiiciently under the influence of spring 2| to cause closure of the contacts l6. After a predetermined amount of counter-clockwise rotation, the pin I2 will engage the lever Il, thus, rotating the member I8 and causing substantially simultaneous closure of the contacts I9 and opening of the contacts 20. Contacts I9 are the main control contacts which upon their closure cause the delayed energization of a controlled device, such as a regulator motor or operating winding. The contacts 20 are normally connected in the energizing circuit of the forward motor element 2 so that operation of the contactor is immediately stopped when it reaches its timed out position. This timed out position is of course characterized by the closing of the contacts l9 and the opening of the contacts 20.

When it is desired to run the contactor back to its normal or reset position the control switch 28 is moved to its lowermost position. This will energize the reversing motor element through the run back contacts [6 and after a predetermined time the pin I will engage the arm l3, thereby causing opening of the run back contacts [6 and automatic stopping of the contactor.

As indicated by the illustrated relative positions of the crank 6 and the gear 8, the contactor is set for a time delay of ten seconds. By pulling out the knob H and rotating the gear clockwise, the time delay may be increased up to seconds and by rotating it counter-clockwise the time delay may be reduced to one second. However, it should be realized that whether the time delay is in seconds, minutes or any other unit of time depends merely upon the speed of the motor l and the ratio of the speed reducing gearing 4,

so that any time delay desired may readily be secured.

While there has been shown and described a particular embodiment of this invention, it will be obvious to those skilled in the art that various changes and modifications can be made therein without departing from the invention and, therefore, it is aimed in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of the invention.

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

1. An adjustable time delay relay comprising, a normally de-energized electric motor having forward and reverse directions of operation, a first rotatable member having a normal position, means connected to said motor for rotating said first member away from its normal position when said motor operates in its forward direction, a normally open set of contacts for connection in a circuit for energizing said motor for reverse rotation, means operated by said first member for closing said contacts when said first member is out of its normal position, a second rotatable member, adjustable means for connecting said second rotatable member to be driven by said first rotatable member at any predetermined angular relation between said members, a set of normally closed contacts for connection in a circuit for energizing said motor for forward operation, means operated by said second rotatable member for opening said normally closed set of contacts after said second member has been rotated a predetermined amount, a set of normally open main control contacts, and means operated by said second rotatable member for closing said main control contacts after said second rotatable member has been rotated said predetermined amount.

2. A time delay control system comprising, a reversible electric motor, rotatable contact operating means having a normal position and mechanically connected to be operated by said motor, a set of normally open contacts for connection in a reversing circuit for said motor, said contacts being closed by said means when it is out of said normal position, and a set of normally closed contacts for connection in a forward running circuit for said motor, said last-mentioned contacts being opened by said means after said motor has rotated a predetermined amount in its forward direction.

3. An adjustable time delay control system comprising, an electric motor, speed reduction gearing connected to be driven by said motor, a first member connected to be rotated by said reduction gearing, a second member connected to be rotated by said first member, means for adjusting the angular relation between said members, and separate contacts connected respectively to be operated by said members.

4. An adjustable time delay control system comprising, a normally deenergized electric motor, a first member having a. normal starting position and connected to be rotated therefrom by said motor, a second member connected to be rotated by said first member, time delayed operating contacts operated by said second member, and means for permitting adjustment of the angular relation between said members so as to adjust the interval between the time when the first member leaves its normal position and the time when the second member operates said contacts.

5. An adjustable time delay control system comprising, a normally denergized electric motor, a first member having a normal starting position and connected to be rotated therefrom by said motor, a second member connected to be rotated by said first member, time delayed operating contacts operated by said second member, means for permitting adjustment of the angular relation between said members so as to adjust the interval between the time when the first member leaves its normal position and the time when the second member operates said contacts, a scale on one of said members calibrated in units of time delay, and a pointer on the other of said units for cooperating with said scale.

6. An adjustable time delay control system comprising, a motor having separate self-starting single phase synchronous motor elements for causing motor operation in forward and reverse directions respectively, speed reducing means driven by said motor, a crank having a normal position from which it is driven by said speed reducing means, a gear arranged for concentric rotation with said crank, a detent on said crank for engaging the teeth of said gear for adjustably fixing the angular relation between said crank and said gear, a set of normally open contacts, means operated by said crank whenever it leaves its normal position for closing said contacts, a second set of normally open contacts, a set of normally closed contacts, and means operated by said gear after it has been rotated an amount corresponding to said angular relation for simultaneously closing said second set of normally open contacts and opening said set of normally closed contacts.

SALVATORE MINNECI.