US1918732A - Automatic electric cut-out - Google Patents

Description

July 18,1933. 5 ADAMs 1,918,732

AUTOMATIC ELECTRICAL CUT-OUT Filed May 9, 1931 2 Sheets-Sheet. l

July 18, 1933. E. ADAMS AUTOMATIC ELECTRICAL CUT-OUT Filed May 9, 1931 2 Sheets-Sheet, 2

Patented July 18, 1933 UNITED STATES PATENT OFFICE ERVIN ADAMS, OF MOUNT CARMEL, PENNSYLVANIA, ASSIGNOR OF ONE-HALF TO MARTIN J. HANEY, 0F MOUNT CARMEL, PENNSYLVANIA, TEN PER GENT T0 SAMUEL W. BLAKSLEE, 0F POTTSVILLE, PENNSYLVANIA, AND TEN C 3153'? TC VZTIILTAM B.

GROVE, OF MERCERSBURG, PENNs'i-YLVANIA, AND I-I'UBEI'RE. V. GROVE, OF EVERETT,

PENNSYLVANIA AUTOMATIC ELECTRIC CUT-OUT Application filed May 9,

This invention relates to improvements in automatic cut-outs and more particularly to a cut-out for employment with a polyphased motor. Difiiculty has been experienced and great expense incurred in the operation of polyphased motors, as, for example, a triphased motor, due to the fact that should any of the leads to the motor break and flow of current is not out 01f, the motor is liable to be burned out.

Therefore one object of the invention is to provide an automatic cut-out so associated withthe circuit for the motor that should any of the leads break, the cut-out will immediately open, thereby breaking the circuit and preventing any danger of the motor becoming burned out.

-Another object of the invention is to provide a cut-out of this character which is positive in its operation and may be very easily installed in a motor circuit without material changes in the wiring.

Another object of the invention is to so construct the cut-out that blades forming part of the same may be easily and quickly v drawn into engagement with cooperating contact-s when solenoics forming part of the cutout are energized, the blades normally remainin in an opened position and due to their resiliency returned to an opened position when the solenoids are tie-energized.

Another object of the invention is to cause bars connected with cores of the solenoids and engaged by the switch blades to move easily whenthe solenoids are deenergized and the blades returned to an open position, means being provided. to prevent too rapid movement of the blade engaging bars and thereby eliminate chattering.

Another object of the invention is to provide a cut-out of this character having as sociated therewith visible indicators in the form of bulbs which are normally burning when the cut-out is-closed but will be extinguished when a break occurs.

This invention is illustrated in the accompanying drawings, wherein:

Figure 1 is a perspective view of the improved cut-out,

Figure 2 is a View taken vertically through Figure 1 showing the casing in section and the mechanism within the casing in elevation,

Figure 3 is a sectional view taken along the line 33 of Figure 2,

Figure 41 is an enlarged fragmentary view showing a portion of a bar and one of the blades engaged thereby, and

Figure 5 is a wiring diagram.

The cut-out embodying the invention comprises a panel 1 of insulating material such as slate or the like and which panel is preferably of general rectangular form and has fitted thereto the open side of a casing 2 which is designed to enclose the operating parts of the cut-out so as to exclude dust and other accumulations of foreign matter and to prevent tampering with the component parts of the cutout. The polyphase motor, which in this instance is of the tri-phasc type, illustrated diagrammatically in Figure 5 of the drawings and is indicated by the numeral 3. Conductor wires 4, 5, and 6 are connected to the binding posts of the motor and serve to conduct current to the several phase windings of the motor. Fixed upon the face of the panel 1 in a vertical series are brackets 7,8 and 9 which respectively support contacts 10. 11 and 12. The wires 1, 5 and 6 are led to and are electrically connected with the several contacts 1O, 11 and 12, respectively, the wires being led into the casing 2, in any suitable manner. The main leads or conductor wires from the source of current supply are indicated by the numerals 13, 14 and 15 and they are connected, respectively, to terminal contacts of the same character as the contacts 10, 11 and 12 and indicated respectively by the numerals 16, 17 and 18, these contacts being mounted upon brackets 19, 20 and 21 arranged in a vertical series parallel and opposite to the series of contacts 10, 11 and 12. Thus the contacts 10 and 16, 11 and 17, and 12 and 18 are located opposite each other in horizontal alineinent.

Mounted upon the panel 1 in vertical alinement between the brackets 7, 8 and 9, and 19, 20 and 21, heretofore referred to, are brackets 22, 23 and 24. Supported by the bracket 22 is a resilient strip bent to form arms 25 and 26 which diverge upwardly. Other resilient strips are secured to the brackets 23 and 24 and form blades 27, 28, 29 and 30. The blades 25, 27 and 29 are provided intermediate their ends with contact buttons de- 7 signed to coactrespectively wit-h the contacts 10, 11 and 12 and have their ends twisted to form relatively thin flat vertical fingers 31 which are curved longitudinally as shown in Figure 4 and engaged in slots 32 formed through a bar 33 of insulating material in vertical spaced relation to each other. Rollers 34 are mounted in the slots and bear against the curved upper edges of the fingers to facilitate movement of the fingers through the slots. The resilience of the blades normally retains them spaced from the contacts 10, 11 and 12, but when the bar is drawn downwardly the arms will simultaneously engage the contacts. The blades 26, 28 and 30 are designed to coact respectively with the contacts 16, 17 and 18 and they are connected for movement in unison and in parallelism by means of a bar 35 similar to the bar and formed with slots 36 through which fingers 37 at the ends of the blades extend. At this point it will be evident that the blades of each series are so connected that they will move in unison but the two series may be moved independently of each other. Brackets 38 are provided to guide sliding movement of the bars 33 and 35.

Referring now to Figure 2 it will be evident that when the blades 25 and 26 are in electrical engagement with the contacts 10 and 16, respectivelv, current will flow from the conductor wire or lead 13 through the contact 16, blade 26, blade 25, contact 10 and through the wire 4 to one phase winding of the motor 3. Similarly, when the blades 27 and 28 are in electrical engagement with the contacts 11 and 17, current will flow through the wire 14, the contact 17, the blade 28, the blade 27, the contact 11, and through the wire 5. to another phase winding of the motor; and, when the blades 29 and 30 are swung downwardly into electrical contact with the contacts 12 and 18, current will flow through the wire 15, the contact 18, blade 30, blade 29, contact 12, and through the wire 6 to the third phase winding of the motor. It is, of course, necessary, that when the motor is operating under normal conditions, all of the blades 25, 26, 27, 28. 29 and 30 be lowered into engagement with their respective contacts so that current will flow from the leads 13, 14 and 15 through the blades and their respective contacts and through the wires 4, 5 and 6, respectively, to

the several phase windings of the motor, and in order that this adjustment of the several blades may be automatically effected at the time the current is turned 011, means is provided which will now be described.

blades is accomplished through the energization of two solenoids indicated one by the numeral 39 and the other by the numeral 40. The solenoid 39 comprises the usual winding 41 and core 42 to which the bar 33 is attached. A conductor wire 43 leads from the bracket 22 supporting the switch blades 25 and 26 to one terminal. of the winding 41, and a conductor wire 44 leads from the other terminal 01'. the winding to the bracket 24 supporting the switch blades 29 and 30, a manually operable switch, as, for example, of the single throw knife blade type, indicated by the numeral 45, being interposed in the conductor wire 43, for a purpose to be presently explained. At this point it will be evident that when the current is turned on, it will flow through the wire 13 to the contact 16, blade 6 and wire 43 to the winding 41 of the solenoid 39 and, passing through the winding and energizing the solenoid, will flow through the wire 41, blade 30, contact 18, and wire 15 back to the source of supply. The energization oi. the solenoid winding will result in r traction of the core 42 and as this core is connected to the lower end of the bar 33 en- ;zaged by the fingers 31 of the blades 25, 27 and 29. all of these blades will be caused to simultaneously electrically engage the cooperating contacts 10, 11 and 12. Retraction of the core through energization of the solenoid winding will be against the tension of the resi ient blades. It will likewise be understood that upon de-energization of the winding of the solenoid, the resilient blades wiil immediately act to move the switch blades 25, 27 and 29 out of electrical engagement with the contacts 10, 11 and 12, respectively, until they assume substantially the position shown in Figure 2 of the drawings and at the same time the bar 33 and core 42 will be drawn upwardly.

Tracing the circuits illustrated in Figures 2 and 5 it will be evident that when the current is turned on, the solenoid 40 will have its winding 46 energized simultaneously with the energization of the winding of the sole noid 39,inasmueh as a conductor wire 47 is tapped to the lead 14 and leads to one terminal of the said winding 46, a wire 48 being connected to the other terminal of the solenoid winding and electrically connected to the contact 18 to which the lead 15 is likewise connected. A manually operable switch 49 of the same type as the switch 45 is interposed in the wire 47. The bar 35 has its lower end connected to the core 50 of the solenoid 40 so that when this solenoid is energized the bar 35 will be drawn downwardly against action of the blades 26, 28 and 30 and these blades moved into engagement with the contacts 16, 17 and 18. It will now be evident that when the current is turned on from the source of supply, both solenoids 39 and 40 will be ener ized thus effecting a downward swinging movement of all of the switch blades into electrical I engagement with their respective contacts and'thereby closing the circuit through the several phase windings of the motor 3.

The motor 3, being in operation, let it be as sumed that the lead 13 becomes broken or disconnected. Current will then cease to flow through the winding of the solenoid S9 and the solenoid will be Clo-energized. The resiliency of the switch blades 25, 27 and 29 will cause them to move upwardly thereby breaking the circuitto the motor throughall three of the wires 4, Sand 6. Should either-of the leads 14 or 15 become broken or disconnected the circuit through the winding 46 of the solenoid will. be broken and this solenoid will" be deeenergized whereupon the three blades 26, 28 and 30 will swing upwardly, thus breaking the circuit through the wires 13, 14 and 15 to the wires l, and 6 through the switch blades. It will be obvious, there fore, that a breakage or disconnection of any of thewires13, 1 1 and 15 will result in immediate automatic operation of the cut-out to prevent any further flow of current through the wires which remain intact, and to the mo tor so that there can be no burning out ot the motor Winding in the event of such a contingency. Socket- s 51, 52 and 5?) can'ying bulbs 54:, 55 and 56 are cut into the wires 13, 14 and 15 and connected with a return wire 57. These bulbs are illuminated except when a-wire 13, 14 or 15 is broken and serve as visible indicators.

In order to prevent the bars 33 and 35 from moving upwardly too rapidly there has been provided dashpots 58 into which extend the reduced upper ends 33 and 35 of the bars, each carrying at its upper end a piston 59 hearing against a light spring 60 which cushions upward movement of the bar. Openings 61 are provided to prevent air being trapped in the dashpots. I

If for any reason it should become neces sary to manually open the circuit, either of the manually operable switches 4. .5 and 49 may be swung open, thereby respectively decnergizing the solenoid 39 or the solenoid 40 and producing the same result as though the cut-out were operating automatically.

lVhat is claimed is: v

1. In an electric cut-out, a vertically disposed panel of insulation, mountingscarried by said panel intermedate its width in vertical spaced relation to each other, contacts spaced from opposite sides of each mounting and adapted to have conductors attached thereto, the conductors attached to the contacts at one side constituting line wires and the conductors attached to the contacts at the other side connected to a motor, strips of resilient conductive material rigidly secured intermediate their ends to said mountings and projecting from opposite sides thereof to form resilient upwardly diverging resilient blades, contact buttons secured to the intermediate portions of the blades and extending over the first mentioned contacts and normally spaced therefrom, pull bars of insulation extending vertically and each slidably receiving the ends of the adjacent blades at one side of said mountings, and electrically energized elements operatively connected with said bars to move the bars downwardly against the tension of the blades and effect engagement of said blades with said contacts when the said elements are energized.

2. In an electric cut-out, a panel of insulation, mountings carried by said panel intermediate its width in vertical spaced relation to each other, contacts spaced from opposite sides of each mounting and adapted to have conductors attached. thereto, the conductors attached to the contacts at one side constituting line wires and the conductors attached to the contacts at the other side being connected to a motor, strips of resilient conductive material rigidly secured intermediate their ends to said mountings posite sides thereof to form upwardly diverging resilient blades extending over said con tacts and normally spaced therefrom, pull bars of insulation extending vertically of the panel and. each slidably receiving therethrough the ends of the adjacent blades at one side of said mountings, and solenoids beneath said bars and having their cores connected to the bars, one solenoid having its coil connected with the upper and lower ones of said mountings and the other having its coil connected with the lower and intermediate ones of said line wires, said solenoids when energized serving to draw the bars downwardly against the tension of the blades and move the blades into engagement with said contacts to complete a circuit through the motor, the tension of the blades serving to elevate the bars and disengage the contacts when the solenoids are de-energized.

3. In an electric cutout, a panel of insulation, mountings carried by said panel intermediate its width in vertical spaced relation to each other, contacts spacedfrom opposite sides of each mounting and adapted. to have conductors attached thereto, the conductors attached to the contacts at one side constituting line wires and the conductors attached to the contacts at the other side connected to a motor, strips of resilient conductive material rigidly secured intermediate their ends to said mountings and projecting from opposite sides thereof to form upwardly diverging resilient blades extending over said contacts and normally spaced therefrom, pull bars of insulation extending vertically of the panel and each having transverse openings formed therein in vertical spaced relation to each other, the free ends of said strips being bent to form relatively thin flat arcuate fingers and projecting from opat the ends of said blades, the fingers being slidably engaged through transverse openings in cooperating bars whereby the blades will be moved into engagement with said contacts when the bars are drawn downwardly against the tension of the blades, and solenoids disposed beneath the bars with their cores attached to lower ends of the bars.

4. In an electric cut-out, sets of contacts spaced transversely and each set having its contacts disposed in vertical spaced relation to each other, line wires attached to the contacts of one set, conductor wires attached to the contacts of the other set, supports between said sets, normally upwardly diverging resilient blades rigidly secured to and extending in opposite directions from said supports and yieldably held by their resiliency out of engagement with said contacts, bars of insulation slidably receiving the ends of companion blades to ei'i'ect movement of the blades in unison, and solenoids having their cores connected to said bars for drawing the bars downwardly against the tension of the blades and retaining the blades in engagement with said contacts when the solenoids are energized.

5. In an electric cut-out, sets of contacts spaced transversely and each set having its contacts disposed in Vertical spaced relation to each other, line wires attached to the contacts of one set, conductor wires attached to the contacts of the other set, supports between said sets, upwardly diverging resilient blades extending from said supports and yieldably held by their resiliency out of engagement with said contacts, said blades being provided with flat arcuate fingers, bars of insulation slidably receiving the fingers of companion blades to effect movement of the blades in unison, and provided with spaced transverse openings, rollers journaled in said openings and bearing against the upper arcuate edges of the fingers, solenoids having their cores connected to said bars for drawing the bars downwardly against the tension of the blades and retaining the blades in engagement with said contacts when the solenoids are energized, one solenoid having leads extending from ends of its coil to certain of said supports and the other having leads connecting ends of its coil with certain of said line wires, and switches to inate fingers of companion blades to efi'ect movement of the blades in unison and provided with openings receiving the terminal fingers, solenoids having their cores connected to said bars for drawing the bars downwardly against the tension of the blades and retaining the blades in engagement with said contacts when the solenoids are energizcd, and means to cushion upward movement of the bars when the solenoids are deenergized.

7. In an electric cut-out, sets of contacts spaced transversely and each set having its contacts disposed in vertical spaced relation to each other, line wires attached to the contacts of one set, conductor wires attached to the contacts of the other set, supports between said sets, upwardly diverging resilient blades extending from said supports and yieldably held by their resiliency out of engagement with said contacts, said blades being provided with terminal relatively fiat arcuate fingers, bars of insulation slidably receiving the arcuate fingers of companion blades to effect movement of the blades in unison and provided with spaced openings slidably receiving said fingers, solenoids having their cores connected to said bars for drawing the bars downwardly against the tension of the blades and retaining the blades in engagement with said contacts when the solenoids are energized, a dash pot above each bar, the upper ends of said bars extending into said dashpots and having pistons slidable in the dashpots and springs in the dashpots engaging said pistons to cushion upward movement of the bars when the solenoids are deenergized.

ERVIN ADAMS. [1..s.]

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