US2566309A - Time-delay relay circuits - Google Patents

Description

G. E. BRODE sept. 4, 1951 TIME DELAY RELAY CIRCUITS Filed Nov. 1o, 194'.'

INVENToR. 650x765 f. 5,9005

Patented Sept. 4, 1951 2,566,309 y rma-DELAY RELAY cmcurrs George E. Brodo, Newark, N. J., assignor to Fed- Yeral Telephone and Radio Corporation, New

York, N. Y., a corporation of Delaware Application November 10, 1947, Serial No. 784,985

2 Claims. (Cl. 175-320) l My invention relates to time delay relay circuits and is particularly directed to circuits for accurately measuring a predetermined time interval after an initiating electric pulse.

2 normally open contacts 5, the winding and contacts being electrically connected in series. Relav 6 comprises winding l and the normally closed contacts 8. With contacts 5 in series with There are numerous applications of time delay 5 winding 4, contacts 5 lock-up once winding I circuits. In industrial counting mechanisms, for is energized. Hence,switch Il is placed across example, a power relay-must be actuated a given the contacts I. time after actual counting by a phototube or a The rst and instantaneous result of the clotrigger ilnger. Heretofore, the necessary time sure of contacts 5, is the ignition of a discharge delay has been obtained by ordinary slow rei in the gaseous discharge device 9, the anodelease relays using direct current power supplies. Cathode Space being COIIHCCted aCrDSS the volt- There is not only no control over the length age SO'JI'C@ 2 through Contacts 5. 'I'he control of the delay period, but it is oftenv inconvenient. 0r starter electrode l0 may be a grid or a pointed to obtain the direct current. The copper-oxide igniiing eleCtIOde and the CathOde ll may be type rectifier is undesirable because of vsize and iof the cold type such as a cold oxide coated memtemperature limitations while vacuum tube recbei 01' a D001 of mercury. Anode potential is tiers employing hot cathodes are not suitable applied to the starter electrode Ill through rebecause of the time delay involved in raising the sistor I2. The discharge current will cause a cathode to operating temperature and because, considerable voltage drop across cathode resistor for intermittent operation, it is eostly to maini I3. the half-wave pulses being smoothed as detain a cathode hot. Alternating current-oper- Sired with condenser Il. ated relays have obvious advantages. Condenser I5 and resistor I6 are connected The general object of my invention is an imin series and across the cathode resistor, the proved time deiey circuit, time constant of this network being adjusted to A more specic object of my invention is a any desiredvalue by adjustment of the values Iinie delay nii-cuit which is simple in consti-unof the condenser I5 and/or the resistor I6. It tion, adjustable as to time delay, and is ecowill more fully appear hereinafter that the time nomical and reliable in operation. constant of this capacity-resistance network A stiii more speciiie object of my invention easily predetermines the delay time of the system. is a time delay circuit that 1s entirely operable 30 The Second gaseous discharge device I1 is also on alternating current. Connected across the source 2 through contacts The Scope of my invention is particularly de- 5. Ignition of a discharge in tube II, and enerilned in the appended claims'and exemplary lemvSizliiorl 0f the Winding 7. must, however, await bodiments thereof are described in the following the Proper potential on the control electrode la, specification vand ShdwnA in Vthe accompanying The condenser I5 is connected directly across drawing in which the grid-cathode of tube I l, so that this ignitpig'e i and 3 are circuit diagrams of two nf ing potential is determined by the charge of the seid embodiments, and condenser I5. Hence, ignition of a discharge Ngs 2 and 4 are time-Sequence graphs of im.. in tube 1 S delayed fOr an interval Of portant voltages of the circuits of Figs. 1 and 3, 40 determined by the timi! Constant 0f the Capacityie5pectiveiy, I resistance network Iii-I6. Energization of wind- AAt il is shown e pu5h bntt0n switch which is ing, 'l opens the normally closed rcontacts 8 of arbitrarily chosen for illustration here to exrelay 6 Which in turn deenel'EiZeS the Winding emplify any switch or key that serves to momen- 4. allOWiIlg Contacts 5 t0 fall Opentarlly close a circuit, the lgsure of which is to A Utilization Cll'cllllL'Ol Circuit t0 be cOVIltI'Olled, be followed by the actuation of certain relays may comprise l.` relay Winding in any Portion 0f in predetermined time sequence and at predetermined intervals. Switch I may. for example, comprise the contacts oi.' a photoelectric-actuated relay of an industrial counter, and the sequential operations to follow may include motor start-stop switching. At I is represented'a voltage source which according to my invention is alternating current. At 3 is an electromagnetic relay of conventional design with winding I and the circuits shown which carries current only during the delay period, or conveniently, aux- A iliary contacts may be operated by the armature of either relay 3 or 8. In Fig. 1, for example. contacts I9 in the circuit to be controlled are operated by the armature of relay 3.- The contacts I9 may be normally open or normally closed. as desired.

56 The sequence o! operations oi.' the circuits of Fig. 1 may be diagrammed as Fig. 2. Switch I is at least momentarily closed and relay l locked up. Contacts I9 close, assuming these contacts are normally open. A discharge in tube 9 is immediately initiated and condenser I5 starts charging. After a. predetermined time grid I8 ignites tube I'I, whereupon Winding 'I opens contacts 8. The then deenergized winding 4 releases and opens contacts 5 and I9. That is, contacts I9 operate at the beginning and at the end oi this sequence, the time interval being measured by the size or capacity of condenser I 5/or the ohmic value of resistor I6, either of rwhich is easily adjusted. The same sequenceiollows each time switch I is closed.

The circuits of Fig. `3 are in all respects the same as the circuits of Fig. 1but with the addie commercial alternating current, -requires no tion of relay windings and 2l specically for I operating contacts I9. The contacts I9, oi the circuit to be controlled, are here mechanically connected withl a common armature for the two windings 2'0 and 2| so that energization of either winding will serve to actuate contacts I9. The l windings 20 and 2| may he placed on Separate or on a common core as desired. Winding 20 is connected across the voltage source 2 back of switch I so that at the instant switch I is closed, the armature of contacts I9 pulls up. Thev other winding 2| is connected in series with resistor 22 and the back and `normally closed contacts A23 of relay 3 across condenser'IS. Thus, with contacts '23 closed, and with condenser I5 charged, winding 2I may also energize and pull up the armature of contact I9.

In operation, closure of switch I locks up rel lay 3 as in Fig. 1, andthe sequence of operations graphically represented in Fig. 4 follows. Contacts 5 close and contacts 23 open. In addition to initiation of a discharge in tube 9, winding 20 is immediately energized and condenser I5 startscharging. After a predetermined time', condenser I5 is charged to asuilicient potential to ignite tube I1, whereupon winding 1 opens contact B, deencrgizing winding 4 andreleasing its armature.V As contacts -5 open, contacts 23 close, connecting the now charged condenser I5 across the winding 2|, and transferring the holdstand-by or idling current, is easily adjustable,

is simple and inexpensive in construction, and

is reliable in operation.

' I claim:

1. Altime delay circuit comprising a voltage source, a lock up relay, said relay having at least one winding connected across said source, at least one pair of contacts controlled by said relay, said winding being in series with said pair of contacts, said source connectedl to said relay for holding closed said contacts, a normally open switch across said contacts of said relay, rst and second discharge tubes .connected in parallel across said source through said pair of contacts, i

a resistorA in the cathode circuit of said rst discharge tube, a capacity-resistance network coning force on the arma-ture and contact I9 from winding 20 to winding 2|. It is assumed in this While in some applications of my time delay circuit, an overlap of the energzation penected in` series across said cathode resistor, a vsecond-relay in the anode circuit of said second tube, normally closed contacts associatedwith saidl second relay, said normally closed contacts .being connected in series with the winding-of said lookup relay. j

l 2. A time delay circuit according to claim 1 and further comprising third and fourth relay windings, ,andal further slet of contacts controlled by saidfirst mentioned winding, said third winding being connected across said source, said fourth wlndingbeing connected in series with said capacity-resistancenetwork, said'third and fourth .windings being alternately energized correspondingly with the energization and deenergization of said iirst mentioned winding.

, GEORGE E. BRODE.

REFERENCESv CITED The following references are of record in the le of this patent:

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