US 2619621 A
Description (OCR text may contain errors)
S. S. BROWN ELECTRIC MOTOR AND SELECTOR SWITCH THEREFOR Nov. 25, 1952 2 SHEETS--SHEET 2 Filed Oct. 4. 1950 220v cc IIO V CW v220v cw cw K 220v cc IlO V ||ov CC 220V CW INVENTOR STEFFEN S. BROWN B m SQ/1%.
Patented Nov. 25, 1952 ELECTRIC MOTOR AND SELECTOR SWITCH THEREFOR Steffen S. Brown, Dayton, Ohio, assigner to The Brown-Brockmeyer Company, Dayton, Ohio,
a corporation of Ohio Application october 4, 195o, serial' No. 188,454
This invention relates to a switching device, and particularly to a switching device adapted for use with an electric motor to change the operating voltage and rotation thereof.
In the ordinary type split-phase motor or in a double voltage motor, whenever it is desired to change the operating voltage or the direction of rotation, it is necessary to remove the conduit or terminal box cover and then change the motor connections at the terminal plate. This, of course, is troublesome and involves the removing of the clamping nuts from the terminal posts and the changing of the leads thereon and then the replacing of the clamping nuts.
According to the present invention, this procedure is greatly simplied, and all chance of error in making such change eliminated by providing a switch which is mounted on the motor and which can be moved to a plurality of positions for effecting the desired changes in the motor connections.
Accordingly, the primary object of thisinvention is the provision of an arrangement for changing the operating voltage or the direction of rotation of an electric motor without the usual procedure of interchanging lead connections at the motor terminal posts.
A particular object is the provision of a switch for changing the terminal connections of an electric motor at any time desired.
Another particular object is the provision of a switching arrangement which can be built integrally with the motor structure and which is readily accessible externally of the motor for making changes in the motor lead connections.
These and other objects and advantages will become more apparent upon reference to the following description taken in connection with the accompanying drawings, in which:
Figure 1 is a perspective view of an electric motor showing a switch of the nature referred to mounted on the side of the motor;
Figure 2 is a View looking in at the switch from the side of the motor drawn at a somewhat larger scale than it is shown in Figure l;
Figure 3 is a vertical section through the switch and is indicated by line 3 3 on Figure 2 Figure 4 is another section lookingin at the contact plates of the switch and is indicated by line 4 4 on Figure 3;
Figures 5, 6, and '7 are views similar to Figure 4 but showing the switch in other operative positions;
Figures 8, 9, 10, and 11 are wiring diagrams of a motor showing how the various motor leads (Cl. S18-202) are connected to the terminal posts of the switch; and
Figure 12 is a fragmentary view showing how an overload protection relay can be included in the motor circuit.
Referring to the drawings somewhat more in detail, the electric motor shown in Figure 1 comprises the usual frame l0 within which are positioned the stator windings and also within which is rotatable an armature for driving the output shaft I2.
Power may be brought into the motor in any suitable manner, as by means of a conduit I4, and connected to the terminals of the windings within the motor frame.
According to my invention, the motor is additionally provided with a switching mechanism, generally indicated at I6, and to `which all of the winding leads and the incoming power lines are connected, so that adjustment of the switch will adjust the operating conditions of the motor.
A somewhat enlarged view of the switch is illustrated in Figures 2, 3, and 4, and in these iigures it will be seen that the motor frame I0 is preferably apertured, as at i8, in Figure 4, for permitting access to the terminal posts of the switch, to which the various leads of the motor windings and the power lines are connected. The switch mechanism may comprise a pair of spaced insulating members 20 and 22 spaced by the spacer sleeves 24 and secured to the motor frame as by screws 23. Any suitably strong insulating material, such as flock, ber, or fabric-filled phenolic may be employed for the insulating disks. Other substances Well-known in the art may also be utilized for this purpose.
Mounted on member 20 are a plurality of studs 28 which are threaded on their one ends for receiving clamping nuts 30, and which have their other ends rounded, as at 32, on the other side of the insulating member for being contacted by the contact elements of the movable part of the switch mechanism. The said movable part of the switch mechanism comprises an insulating disk element 34 having riveted or otherwise suitably aixed thereto the contact plates 3S and 3f?. As illustrated, rivets 40 secure the contact plates to element 34, but it will be understood that other means could be utilized, if desired.
Insulating disk 34 is suitably mounted on a shaft 42 which preferably has its opposite sides iiat, as at 44, so that rotation of the shaft will also rotate the said disk. A spring 46 bears between insulating member 22 and the back of disk 34 and thereby continuously urges the said disk the other well-known means that may be employed for shifting the phase of the current in Winding 14 or for interrupting the circuit through winding 14, or both.
It has been mentioned that this invention is adapted for use in connection with motors hav- '.ing--an overload relayiincircuit;andf'this is in- .idicatedxin Figure l2,-.wherein1thereis' placed in series with line L2 the overload relay 80, so that Allofgwhenever the running winding of the motor .becomes overloaded, the said relay will open and :ininterrupt'the supply of power to the motor. So far as the switch of this invention is concerned,
toward the ends of studs 28 to hold contact plates 3S and 3G in good electrical contact with the said studs. A bushing S supports the one end of shaft 52, and nuts 56 secure the shaft against axial movement in one direction.
A shoulder 52 on the shaft on the opposite side of insulating memberl provides abearing for preventing axial movement 'of the shaftv in the other direction and the said shaft is thus held in its proper location at all times while rotation thereof is permitted for adjusting disk 34.
The aperture i8 in themotor frame'iszenclosed by a cover plate 54 secured to the frame by screws 55 and through which the-*shaftiexinthe;introduction-of the overload relay involvesV tends for receiving the indicator-.59).` Indicatorf has a pointed end E adapted for registering with the indicia E2 for indicating the` operating. conditions of the motor for each particular switch adjustment.
Inasmuch as the switch will ordinarily remain in; an adjustedposition for a considerableilength of time, plate d may comprise a plurality-of ...threaded'holes-S adapted-for receiving afscrew A`-5l extending through -indicatorg wherebythe indicator may be locked in each of its-operative. i positions.
'.'Turning for the moment Vto Figures 8 through l1, there isshown1the wiring diagramror aspl-it- 'aphase' motor of thedouble Voltage type having y"running windings'l' and2 and a starting .wind-A ing 14. The studs 2S which are mountedffin in- .sulatingrnemberl are*v connected withl the ter- `minals of Pthe windingsas illustrated. Thus,
f'rwinding 'l0 hasone'end connected;toither-terminal marked I, and its other'end 'connected-tc;y
C. vthe terminal marked 2; winding l2 has its one end connected `Iwith-the terminal,A marked S', and its i'otherlendconnected to thepterminalI marked pand :winding 'llzfhas onef .end :connected to y.the
1 :terminal marked 8, .and its other .endzconnectedg to :the terminal marked.
; Power tlinei `L l 1 is connected .withthe ;.terminal I, :and :power lineLZ.Y is connected with terminal f. 4. 1Alli-,other connection's'between' the terminals .5.; are effected Kbythe .contact plates i 35 .and'x S. f off'Y i'fhegselector switch fof this invention.
"Atgthis pointp itniayfloe noted' that` the switch .layoutsgof Figures Llithrough 7 each .indicateseven .terminalsg'and this1is-accounted orby the-'fact ;that;twofo the terminals are connected together, ..'thusgiving.twosconnections'for the :terminal stud :smarked 2. .Thisiisdone because'. it "somewhat ;;.;simplies the construction ofthecontact-'plates -...ofithezfswitch. l
'- It may Valso berpcintedoutithatf the: order.. int:
which the terminal1studs are` indicated-...in Fig- .ures 81 through '311:A is ".not theusame v.as :the order tifying' numerals applied to the terminal: studs correspond-for'all of theviews.
'-The motor -or the diagram Vof'lFigures 8 through 1l may `he a'v split-phase motor of the rupt the circuitfthrough the starting Vwinding when the armature'of' the motor :attains 1 -pre-r determined speed.
` Thisfhas been/indicated in'fthe drawings-by P the rectangle 'F16 whichv is A-intendedtorepresent fthecentrifugalswitch, or-the vcombination of aA condenser and a centrifugal switch, vorl any of' Jl 5.an'o changeswhatsoever.
l'Y Returning now: to the switch proper, Figure 4 illustratesthe manner in which the contact Figure 4 that.theterrninall studsare generally a. located. onf-two 'loa-se...circlesI which-.are-radially spacedso f the rivets 40 caribe positionedoon'ian intermediate fbase f.- circle -iand. thus `prevent? the rivets 'from interfering with the contacting of the studs bythe contact-plates.
this mannemtis, insuredrthan .thereaviu -always vbe fproper-- contact made .and .no-:undue f wear-on .the studsor contact Aplates willyoccur. Contact plate 36 is fa4 simple l arcuatemembersexvtending aboutv approximately 11345. degr eesof.the peripheryof-the insulatingidisk .34..andhaving a notch AV82 .thereinwhich will register with the one stud marked .2,1 as 'wille-.be .seen irri-Figurev 6. The other. contact.-.plate -38 extends eabout slightly. more..than l'rdegreesloflthe periphery of the: disk x34 and-.has its .endsspacedifroni the Y -.ends Vof contact plate A-36. Contact lplate t is.-.notched, fasi-at 84, lfurthepurpose.Otxearing .'thecontactstuds marked land 2..in-icertain.-posi tions of the switch, as will .be.seen.i`r'il..F'igures 4 through 7.
- `Operation fInorder more fully tdi'sclosethe natureand operation Aof the switching- "arrangement of 'ithis invention, reference' may fbe'f lhad Ito" Figures 4 through 7 taken inconneotion'withFigures 8 through-'1 1, respectively.
In Figure 4 vthefswitchfv is shown. .adjusted-1f to the position where the operating voltage' is i110 andthe direction of'rotation-is-lcounterclockwise. V'-With" the switch this 'positionftermirialsl lf; 3, and 5'a-re connected togetherrandterminals:2i 4,
'and 8 fare' connected* together. *'it'lnasmuchf "line LI is connected'to terminal l'andlnellzflsrcon- 'f nected toter'rninal 4;'"this results inthe-arrangement disclosedV in Figure l8,whereir'ith'fr1IIining other and with'startingwinding'lll.
'To adjust the motorto `counteifc'zlockwise"rotation with the same voltageobtainingf;the-:switch may be indexed ina clockwise directionf'byremovingthe screw-66 'and turning f the indicator so that pointer rB points tol thel indexforl LtheIlO -the index marked CC.onjthe-1f220lyoltnside,Lthe' connections shown in Figures 6 and 10 are obtained. In this case, terminals 2, 3, and 5 are connected together and terminals 4 and B, with terminal l not being interconnected with any of the others.
Reference to Figure will indicate that the running windings 'I0 and 12 are now in series between the power lines Ll and L2, and that the starting winding 14 is in parallel with running winding 12. Thus, each of the running windings is subjected to 110 volts, as well as the starting winding. It will be noted in Figure 6 that the notch 82 is in register with the terminal stud 2 toward the right-hand side of the view, and that the terminal stud 2 toward the left-hand side of the view is in engagement with contact plate 38.
In order to adjust the motor to clockwise rotation under 220 volts, indicator 58 of the switch is turned until its pointer 60 points to the index marked CW on the 220 volt side. The position of the switch that this produces is illustrated in Figure 7 and the motor connections in Figure 11.
It will be noted that terminal I is still not connected to any of the others of the terminals, that terminals 2, 3, and 8 are connected together, and that terminals 4 and 5 are connected together. The conditions within the motor are then the same as in Figure 10, except that starting winding 14 is reversed relative to the running windings 'l0 and l2.
It will be seen from the foregoing that my invention provides for a relatively simple switching arrangement for incorporation in a splitphase electric motor which makes it very convenient to change the operating voltage of the motor or to change its direction of rotation without the necessity of ever having to change the connections at the terminal box of the motor in the customary manner.
The switch is inexpensive to manufacture and nals are individually connected, said plate forming a part of a switch comprising a movable part having contact members thereon engaging said receiving the wires to be connected to the tercan readily be incorporated in a motor structure at the time of manufacture. The switch is accessible for adjustment at all times and is adapted for being locked in each position of adjustment, thereby insuring that the switch can not accidently become moved to an improper location.
The arrangement of my invention has been described and disclosed in connection with the usual type single-phase double voltage splitphase motor. It has been explained how it can be used with either a straight split-phase motor or with a capacitor start motor, but it will beunderstood that this 'mvenuon is also adaptable for other types of motors, for example, double voltage two-phase motors, double voltage three-phase motors, as well as electrical reversible motors and other types where changes in motor connections are made to adapt the motor to diierent usages, are all ideal subjects for combination with a switching device according to my invention.
It will be understood that this invention is susceptible to modication in order to adapt it to different usages and conditions, and, accordingly, it Vis desired to comprehend such modifications within this invention as may fall within the scope of the appended claims.
l. In combination: an electric motor having a frame with a stator therein having a plurality of windings with terminals, an aperture in the wall of the frame, a terminal plate mounted over the aperture inside said frame having a plurality of terminal posts to which said termiminal posts.
2. In combination with an electric motor having a pair of running windings and a starting winding all with terminals, said motor having a frame with an aperture in one wall, a terminal plate mounted in the frame over the aperture having posts to which said terminals are individually connected, said plate forming a part of a switch comprising a single movable part having contact members thereon engaging said posts, a shaft connected to said part and extending out the aperture, said movable part having a first pair of positions wherein all of the windings are in parallel for operation of the motor at a lower voltage and a second pair of positions where the running windings are in series and with the starting winding in parallel with one thereof for operation of the motor at a higher voltage, said starting winding being connected in circuit in one direction for one of each of said pairs of positions and in the opposite direction for the other of each pair of positions, whereby either direction of operation of the motor can be had :for either voltage, a cover plate outside the frame closing said aperture and through which said shaft extends, a combination indicator and turning knob on the outer end of the shaft, indicia on the cover plate to indicate the four operative positions of the said movable part, and means for clamping the indicator to the cover plate in only the said four positions.
3. In combination: an electric motor having a frame with a stator therein having a plurality of windings with terminals, an aperture in the wall of the frame, a terminal plate mounted over the aperture inside said frame having a plurality of terminal posts to which said terminals are individually connected, said plate forming a part of a switch comprising a movable part having contact members thereon engaging said posts to connect the windings, a shaft connected with the movable part extending out said aperture, said part being movable by actuation of the shaft to change the windings from series to parallel connection and to reverse the direction of rotation of the motor, an indicator on the outer end of said shaft, and a cover plate closing said aperture and bearing indicia to register with said indicator, means for locking said indicator to said cover plate in each position of said movable part, the space between the terminal plate and cover plate defining a space for receiving the wires to be connected to the terminal posts.
4. In combination: an electric motor having a frame with a stator therein having a plurality of windings with terminals, an aperture in the wall of the frame, a terminal plate mounted over the aperture inside said frame having a plurality of terminal posts to which said terminals are individually connected, said plate forming a part of a switch comprising a movable part having conneotithe windings@ shaft connected with the;
moyable `part extendingVV out `said aperture, said papt'being movable -by actuationo the shaft to change;` the windings-.from series to parallel connecton andto reverse-the direction of rotation oi-the motor, a back .plate spacedfrom said terminaLplate` behind*` saidv rotatable member :for supporting said shit and spring means positioned'between said,` movable member andsaid back-plate forfurgingl said contacts against said posts.,V an indicator on the. outer end of said shaft, and aA cover plate closing-said aperture and bearingindica. to.v register with said indicator, the space between the terminal plate and .cover plate defining kva Space forreoeiving the .Wiresto vbe connected tothe terminal. posts.
SFIEFINv S. BROWN..
REFERENCES' :CITED '121145 ,followingreferences.u are of record in Vthe le Vof:this,patent:
Number 15 lNTLunber