US2385779A

US2385779A - Electromagnetic circuit controller

Info

Publication number: US2385779A
Application number: US494279A
Authority: US
Inventors: Clarence T Evans
Original assignee: Cutler Hammer Inc
Current assignee: Cutler Hammer Inc
Priority date: 1943-07-12
Filing date: 1943-07-12
Publication date: 1945-10-02
Anticipated expiration: 1962-10-02
Also published as: GB580278A

Description

Oct. 2, 1945. c. T. EVANS ELECTROMAGNETIC CIRCUIT CONTROLLER Filed July 12, 1943 max I 42/ 5. 81mm @g wvwk a;

I i fifm ua x ing in both time and Patented Oct. '2, 1945 it ELECTROMAGNETIC cmourr CONTROLLER Clarence '1. Evans, Wauwatosa, Wis, assignor to Milwaukee, .Wis., a cor- Cutle'r-Hammer, Inc poratlon of Delawar Application July 12, 1943, Serial No. 494,279

A (or. 115415) 4 Claims.

This invention relates to electromagnetic cir-- I cult controllers and is particularly applicable to those for use aboard ships or in other locations where severe shocks are likely to be encountered and where large switches are required.

i As will be understood, the demand for switches to meet test for severe shocks extends to large switches as well as tosmallswitches oi the relay type of which several forms have been designed and developed to possess inherently the required characteristics to meet test or the aforementioned character. Also as'will be understood, redesign of a complete line of switches of dinerent sizes isboth-very costly and time consuming.

e test to be met does not require that the of more: than momentary break and also against possibility" of circuit making when the switch is supposed to be open, and the present invention has among-its objects to'affordthe needed characteristics to a switch not inherently possessing the same, and by way of. simple additions savcost as compared with redesign. p x

Another object is to provide means to thus render shock proof switches subjected tocontrol in various ways including the so-called 3 wire control afl'ording' low voltage protection.

Various other objects and adva'ntages of the invention will hereinafter appear.

According to the present invention it is proposed to aflord the needed characteristics to a switch not inherently possessing such characteristics through'coordinating therewith one or another of therelativelyinexpensive relays which have been designedto possess inherently the switch be restrained against.m0mentary break circuit butdoes require protection against characteristics required to meet tests of the afore mentioned character..

The accompanyingdrawing illustrates schematically and diagrammatically one embodiment or the present invention which will now be describedyit being understood that the embodiment illustrated is susceptible of various modiilcations without departing from the'scope of the appended claims. I

In the drawing,

Figure 1 is a more or less schematic view of the switch and associated relay, and

Figs. 2 and 3 are diagrammatic views of diiferent control circuits for the switch and relay.

Referring to Fig. l, the switch schematically illustrated therein comprises stationary contacts 1 and 2 carried by a suitable fixed support 3 and cooperating

movable contacts

4 and 5 carried by the armature 6 of a suitable electromagnet. The electromagnet as shown comprises a winding 7 carried by a magnetic frame 8 having a portion 8 constituting a supporting core for the winding 1. The armature 6 has an angular extension I 0 which may be assumed to coact with part of the magnet frame 8 to limit outward movement of the armature 6 under the force of gravity to disengage

contacts

4 and 5 from contacts I and 2. As will be understood, winding 1 is energizable to effect attraction of armature 6 for engagement of

contacts

4 and 5 with contacts I and 2 and as will become apparent the switch might assume various forms other than that illustrated.

The associated relay selected for illustration (see Fig. l) is of a form now in use and disclosed in a pending application assigned to the assignee hereof, Serial No. 493,81l,.filed July 8, 1943, by C. W. Kuhn. This relay briefly described comprisesan electromagnet having a stationarily mounted winding l2, and axially aligned magnet plungers l3 and I4 therefor biased apart by springs I5 and I6, respectively, and adapted to be drawn together electromagnetically upon energization of winding l2. The plungers l3 and H carry respectively at their outer ends across bars I! and I8 in turn respectively carrying contacts l9 and 20. These contacts are separated by the plungers I3 and it when moved apart and are engaged by attraction of the plungers upon energization of winding l2, the contacts being thus afforded rectilinear movements for engaging and disengaging. While in practice the contacts l9 and 20 preferably are additionally afforded limited rocking play against the bias of suitable springs, thus being yielding when brought into engagement, this detail has been omitted from the schematic showing. The floating structures comprising the plungers and the contacts carried thereby are preferably balanced and are interconnected to prevent at all times independent movements thereof and to subject them to counteraction one by another under shocks. This interconnecting means is shown as comprising a disk 2i having a fixed axis 22 and I

arms

23 and 24 which respectively link the cross bars I! and I8 of the two plungers to the disk 2| vat diametrically opposed points on the disk equally spaced from its axis.

Also in practice the biased movements of the plungers are limited by suitable means not illustrated in the schematic showing. Such a relay, as aforeindicated, has

been found to meet satisfactorily severe shock test regardless of direction of shock.

The aforedescribed relay is associated with the switch both mechanically and electrically. Considering the mechanical association the relay is used to control a latch to lock the switch in open position. This latch is shown schematically as comprising a double ended lever 25 having a fixed pivot 28, the upper end of the lever being adapted to underlie the extension It of the armature of the switch when the switch is open, and

the lower end of the lever having a suitable connection 21 with the relay through a link II. The arrangement is such that when the switch and relay are deenergized the relay plungers under their bias throw the lever 25 into interlocking relation with the switch to block closure thereof, whereas energization of the relay winding effects movement of the plungers to swing the lever 2| chanical influence of the relay through the latch lever 25. To make the switch when closed sufficiently shock-proof to meet the aforementioned test which permits, of momentary break of circuit by the switch the relay is used to afford a maintaining circuit for the switch winding I so long as closure of the switch is desired. This the relay will accomplish because it is inherently shock-proof and with the switch supplied uninterruptedly with current if said switch opens under shock it will be quickly reclosed with at the most mere momentary interruption of circuit. Different ways in which the relay maybe so utilized to protect the switch winding against interruption or supply of current to winding 1 are depicted in Figs. 2 and 3.

Referring to Fig. 2 which shows one form of so-called 3-wire control, the windings l and I! are arranged to be supplied from a circuit 33- under the control of a normally closed push button switch and a normally open push button switch 36. Supply of current to the winding 1 is dependent upon prior response of the relay to engage its contacts l9 and 20. When the push button switch 3! is closed it connects the relay winding I2 across the circuit 3lfl through the normally closed push button switch II, whereupon said relay responds to connect winding I across said circuit through the normally closed push button switch 3!. Thus energization of switch winding I is not dependent upon continued closure of the normally open push button switch It and relay contacts l9'and 20 when eneaged shunt the push button switch it, wherefore the relay winding I! will remainenergized upon release of push button switch 38. This provides for continued energization of winding "I so long as the relay winding i2 remains energized. and as aforestated energization of the latter will be continuous regardless of shock, assuming continued normal voltage. Should abnormally low voltage occur the relay would, of course. release. deenergizing the switch winding 1, insuring against reenergization thereof pending restoration of normal voltage and pending reclosure of push button switch 36.

Referring toFig. 3, the same also shows a socalled 3-wire control for the switch winding I comprising a normally closed push button switch I! and normally open push button switch it like those of m. 2, but in this instance the relay is provided in addition to contacts I! and 2| with other contacts 31 and fl, to afford separate maintaining circuits for the two windings. More speciflcally, contacts I! and." control the circuit of the switch winding I just as in Fig. 2, whereas the relay contacts 81 and 38 establish for the relay winding I! a maintaining circuit shunting the push button switch II. This arrangement is in practice usually preferred to the arrangement shown in Pig. 2, and the additional relay contests may comprise another set of contacts like contacts II and 2| or may comprise certain of the auxiliary contacts with which the relay of the type shown is commonly provided, preferably of that type disclosed in the aforementioned Kuhn application.

It will, of course, be understood that other forms of shock-proof relay may be substituted for the particular form shown for illustration.

What I claim as new and desire to secure by Letters Patent is:

1. The combination with an electromagnetic switch, likely under severe shock, when said switch is either energized or deenergized, to effect circuit commutation, of an electromagnetic relay of greater stability under likeshock, and means coordinating said relay with said switch electrically and mechanicalhr to enhance the shock proof characteristics of said switch when energized or deenergized.

2. The combination with an electromagnetic switch likely when energized or deenergized to eflect circuit commutation under sever shock, of control mean therefor comprising an electro- 0 magnetic relay having greater stability under like shock, said means locking said switch in a fixed position when said switch and said relay are deenergized and said means when said'relay is energized maintaining said'switch energized whereby any change in position of said switch when said relay is energized will be only momen- 3. In combination, an electroresponsive switch, an electroresponsive relay having under severe shock, when energized or deenergized, greater stability than said switch, circuit connections rendering said relay and said switch responsive progressively with said switch under the control of said relay for initial and continued energization of said switch, and locking means under the control of said relay to restrain said switch in a ilxed position under severe shock when said switch is deenergized.

4. In combination, an electroresponsive switch,

an electroresponsive relay having under severe shock, when energized or deenergized, greater under the control of said relay to'restrain said switch in a fixed position under severe shock when said switch is deenergized.

CLARENCE T. EVANS.