US1470896A - Starting switch - Google Patents

Description

' Octfm, 1923.. y 1,470,896

H. L. VAN VALKENBURG l STARTING SWITCH Filed Dec. 3o,y 1919 4 sheatsheef 1 H. L. VAN VALKENBURG Oct. 16, 1923.

STARTING SWITGH Filed Dec. 50. 1919 4 Sheets-Sheet 2 Oct. 16, 1923.v f

H. l.. VAN VALKENBURG v STARTING SWITCH Filed Dec. 50, 1919 4 Sheets-Sheet 3 Patented Oct. 16, 1923.

UNITED STATESv PATENTv OFFICE,

HERMON L. VAN VALKENBURG, OF MILWAUKEE, WISCONSIN, ASSIGNO'R T0 INDUS- TRIAL CONTROLLER COMPANY, OF IVIILWAUKEE; WISCONSIN, A CORPORATION OF i WISCONSIN.

STARTING SWITCH.

Application ledDecember 30, 1919. Serial-N0; 348,332'.

To all 'whom t may concern: f f

Be it known that I, HERMON L. VAN VAL- KENBURG,' a citizen of the .United States, residing at Milwaukee', in the; county of Milwaukee and State of lVisconsin, have invented a certain new and useful Improvement in Starting Switches, of which the following is a specification. Y

. My invention relates to startersfor elec#v is no harm in throwing the motor t'erm'nals y directly across the line in the first instan ce; but when this is done the initial inrush of current is usually so greatlas to blow the fuses. It has, therefore., become recognized as good practice to iirstconnect the motor to the line thru a path ,which does not inl, clude the fuses and then when the motor hasA attained sufiicent speed to generate the.

necessary counter E; M. F cha-nge the connections so that the current will thereafter be supplied thru the fuses. One object of my invention is to provide apparatus so constructed as to compel the operator to start the motor in the manner stated. According to the design illustrated, when the operator .moves the handle from of position to startl ing position, \ity first causes a `subsidiary switch to close, thus-establishing a `by pass or shunt around 4the fuse. The continued movement of the handle then closes themain switch and the current passes direct from the source of supplyto the'motor. The handle is now in. starting position. The operatorthen moves the handle part way backward, (or he'may simply release it, as the handle tends automatically to move part way back) whereupon the subsidiary Aswitch opens the shunt circuit and the current flows thru the fuses and mainswitch. The handle is now in running position. It is left here until it is desired to stop the motor, whereupon the 'operator moves the handle still further backward'to initial or off position thus opening the main'switch My purpose is-to 'render the mechanism automatic with respectl to the most'important steps or at .least to make it impossible to operate itin improper sequence. Another object of the invention is tofprovide protective mechanism by enclosing the operating parts in a box,` or housing furnished with a cover and supplyswitch cannot beclosed until the door has been closed and the door cannot be opened' vwithout first opening the switch.

I obtain my objects byl the mechanism illustrated in the accompanying drawings in which, i

Figure l is aigeneral perspective view showing the outside ofthe apparatus. This view shows the operating handle and indi- Cates the off, start, andl run positions thereof.' tric motors. In starting small motora there l Figure 2 isa perspective view of the appa- Figure 5 is similar to Figure 4, but shows l the position which the parts will occupy when the handle is vmoved part way toward start position. The subsidiary switch hasv been closed but the main switch is still open. Figure 6 is similar to Figure .5, but shows the position which the parts occu y when the handle yis in start position. ereboth switches areclosed." i

Figure 7' shows the position`v vwhich the parts will occupy when the handle has moved'backward from startingto running position. I

Figure 8 shows the parts in the same position as in Figure 7, but certain elements are shown in .section in order to give a better understanding of .the parts. Figure 9 is a diagram principle .of the apparatus.

Like numerals denote `like parts thruout the several views.

In the form selected to illustrate the ,invention, the operating parts are enclosed within a box 1 made usually 'of metal and in cover 3 which for convenience may -be provided with ahandle 4 for openingand'closing it. By reference to. Figures 1 and 2, it

-will be seen that provision is also made whereby the box can be padlocked, the cover havingya flange jsuitably apertured to accommodate a post 7 rising from the top of the box. This post is apertured and the reillustrating the lthe resent instance having flanges 2, 2 Y

e immesse means ot a handle which7 as best shown in Figure 3, is journaled in one ot the side walls of theI box and is rigidly connected to a bail 11. .The bail is located within the box and is coaxial with the operating handle. 1t has two side arms 13, one of which is pivotally supported 'on a pin 12 fastened to ythe wall of the box.

hastened/to the back ot the inside of the box is a panel ot slate or other insulating material. Near the bottom of this panel are binding screws 1G Jfor connection to the supply conductors 17 shown in Figure L1. The illustrated device is tor a three wire system of distribution and is therefore a three pole.

- switch and the binding screws are three in number. Similarly, there are three binding screws 18 for the distributingl conductors 19; but it will be understood that the number. of poles is immaterial. yThe screws 16 hold the conductors 17 in contact with terminals-21 which are electrically connected to stationary conductive brackets 22 provided with fuse clips 23. Said terminals also have contacts 2st adapted to be engaged by discs 25 whose function to. bridge the gap between said contacts and the corresponding contacts 26 located opposite to them. The contacts 26 iorm part ot the conductive strips 27 and are electricallyv connected to stationary conductive brackets 28 provided with tuse'elipsv 30. the latter beng adapted to cooperate with the clip 23 to hold the fuses 31. 1t will be evident that when the discs 25 are out ot engagement-with' the contacts 241, 26, as shown in Figure eh current will pass from the supply conductors thru the brackets7 clips, and fuses to the strips 27, but when thel discs are in engagement with said contacts, the' fuses will be short circuited and the discs will bridge the gap .between the contacts and permit the current to pass direct-ly from one to the other.

rThe strips 27 are electrically connected to conductive posts to which the switch blades 36 are pivoted. The pivotal axes of the switch blades are substantially in line with the axisot the bail 11. Said blades are adapted to be rotated into engagement with the Fixed aws 38which are electrically connected to the terminal strips L10. Strips L10 are electrically connected to the' binding screws 18. The switch blades are all tastened to the cross bar 43 which 'is of insulating material and of rigid construction and affords means for compelling the switch blades to operate in unison. Said cross bar and blades are swung to open and closed position by means ot flat bars 15 which are rigidly fastened to said bai; and have tingers G at the upper end and fingers 17 at the lower end. By preference, the bars are curvedv so' as to be approximately concentric with the axis of the bail and ot the switch blades. Said bars in the present desigmare two in number and they are bolted or otherwise rigidly fastened to the cross bar. Their lingers 46 and 117 are so placed to be in the path Vof the cross bar ot bail 11 as the latter rotates about its axis; and the proportions are such that when the bail is swung to its uppermost position7 as shown in Figure G, the switch blades 36 will engage the jaws 3S and the switch will be closed. itter this the bail may be swung down 'for a considerable distance before it engages the lower fingers a7. Aturther downward movement ot the bail after it has engaged4 the lingers 7 swings the switch blades out ot engagement withY the jaws and opens the switch. The first mentioned position in which the bail is at its highestpoint corresponds to the start position as will presently more tully appear.

I have now described the opening and closing of the main switch by means of the bail and the fingers 4G and L17 ot the segmental bars 45. I will next describe the operation of the subsidiary switch. This has discs 25 which /are freely slidable upon rods 50 rigidly secured to but. completely insulated trom a cross bar 52. While the precise method ot' insulation is immaterial` it is accomplished in the )resent design largely by means of the insu ating washers 53. The rods are surrounded by helical compression springs one end o1 which abuts the lower washers and the other end bears against the discs to yieldino'ly hohll them in contact with the stop pins 5r at the lower end ot the rods.

Cross bar 52 forms part ot a second bail having side arms C() pivoted upon the stationary pins 61 secured to the sides oi the box near the top. The discs 25 are moved into and out ot' engagement with the con tacts 241, 2G by the movements ot this second bail about its axis. This bail is biased to open position by helical springs (51, one end .of which abuts thetop ot the box and the other is anchored to the bail arms GO. The second bail is operated by the main bail 11, the side arms 13-ot which lie in tront ot and are adapted to engage the lugs 65 on arms 60 to' promote the wearing qualities ot the apparatus. These lugs may be rounded at the lower` end where first engaged by the bail arms 13, see Figures f1 to 8. The parts are so arranged and proportioned that when the operating handle and main bail are in oft osition, which in the present design is the owermost position, the main bail will he out of engagement with the lugs 65 and the springs 64 will hold the discs'25 in open position out of engagement with their contacts 24, 26, but when the handle is rotated upward toward start position, the side arms 13 will engage the lugs 65 and move the discs y into engagement with saidcontacts and short circuit the fuses.

curs before the cross arm 11 of the main bail This conditionochas closed the main switch. Consequently vwhen the main bail has moved far enough to actually close themain switch -the current will flow, not thru the fuses, but around them: that is, thru-a shunt or short circuiting path formed by the contacts '24, discs 25, and contacts 26. y

' The cycle of operation of the parts thus far described is as follows: Assume that the operating handle 10 is in lowermostor off position in which case the parts will be in the positions shown in Figure 4. If now the operator lwishes to start the motor, he grasps the operating handle and moves it `forward (in the present case, upward). As the handle advances, the main bail, which moves with it, engages the lugs 65 of t-he second bail' and causes the latter to'bring the discs 25 into engagement with their con-l tacts. The parts are now in the position shown in Figure 5. Incidentally during this vmovement the main bail picks up the main e switch by engaging the fingers 46 which are fastened to it. But the main switch does not close until the handle has reached starting position at thepforward end of the travel. The parts are now in the position shown in Figure 6 and the current passes frorn'the supply conductors to thedistributingconductors thru the short subsidiary switches 25 and the main switch blades 36. Consequently the fuses are protected against the initial inrush of current. The operator next permits the handle to move in theA reverse directionthat is, towards running position which in the present case is about half way between the start and ol" positions. As the handle moves backward the main bail l1 permits the springs 64 ofthe second bail to lI'nove the discs 25 out of engagement with the contacts'24, 26. The apparatus isthen in running condition and the parts are in the positions shown in Figures 7 and 8. The reverse movement of the main bail does not open the main switch at this time because the jaws 38' frictionally engage the switch blades and hold them in closed position.

The operator may now remove his hands from the handle and the motor will continue to run with current supplied thru the fuses. When he desires to stop the motor, he

, swings the handle down I to off `position which causes the main bail to engage the fingers 47 and open-the main switch. The parts then return to the position shown in Figure 4.

t is not necearyL for the operator to consciously return the handle from startto run position. All that is necessary is for him to let go ofthe handle after he has moved it to start position, whereupon gravity and the action fof the springs 64 will move it'to start position where it will be arrested lby the contact of the main bail with the lower fingers 47. It will hence be evident that the device is incapable of misoperation for if the operator when intend! ingfto start simply moves the handle from off to run position themain switch will notI close and no current will be supplied to the motor.` He mustmove the handle fully to start position before the motor will start at all and after he has done this, he need not make any movement other than to release the handle', Ifvleft to itself, the apparatus will automatically assume running condition with the fuses ,in circuit.

It will be observed that in the form shown 1 whenthe handle `is" in off position `the two switches'are in the same condition-that is,

is moving backward. This is here made possible by the last motion Iof the handle relatively to the 'main' switch due to the fact that the main bail does not 'pick up the lingers 47 until after it has moved a considerable distance backward and in the meantime permitted the subsidiary switch (discs 25) to open. l

In order that the electrical relationship of the parts may -be readily understood, reference'y is made to the diagram, Figure 9, .In this ligure the parts bearthe same referenee numerals 'as in the other figures, ex-

cept that the 'counterpart of the circuit clos` ing element 25 v'of the starting or subsidiary switchis conventionally lillustrated by thev element 25a'. By referring to the diagram arein series with eachother and that'the protective device 31 is arranged in shunt with the subsidiary or starting switch and is controlled by it.

Now referring to the locking mechanism lby which the cover is prevented from being opened when the switch is `closed and vthe switch is prevented from being closed when the cover is open:

A lug 70 is screwed or otherwise fastened lto the inside of the cover near the lowerend thereof. This lug is here shown to be approximately Z-shaped, one iiange lying in Contact with and bein-g fastened to the cover as best shown in Figure 2. Under ordinary conditions the onlyA necessity for opening the ico vit will be readily seenv lthat the two switches open position. But the lug hasother locking functions: Loosely pivoted upon the stationary pin l2 i's a locking plate 75. TWhen in normal non-acting position, as shown in Figure Al, it lies entirely out ot' the path ot theJ lug 70 and hence permits the covento open. The plate is so designed that gravity tends to hold it in this non-acting position.V

i-'it its upper edge the plate has a lug 'T6 adaptedfto be engaged and moved upward by one of the side arms 13 of the main bail. When the bail is in oil position with the switches both open, the plate will permit the locking lug T() to pass, and it will be iiietlective upon lug T6, but as said bail is moved forward it rotates the. locking plate and causes it to move its locking edge 75, into the path of the flange T01 ot the locking lug. This holds the cover closed. open the locking lug willA occupy thc position shown in dotted lines in Figure 4- and will obstruct the movement otI the bail ll and prevent it from closing the main switch. Thus the lug TO locks the cover closed so long as the switch is closed and locks the switch open so long` as the cover is open.

As a matter of convenience, a'lug 7S is outstruck from plate 75. This prevents the main bail Jfrom swinging too far downward-that is, past ott' position.- The saine effect, however, but in a less advantageous way may be accomplished by fastening a bracket 79 on the outside ot the box as shown in Figure l. e

Having thus described my invention what l claim as new and desire to secure by Letters Patent, is

l. A motor starter having a'main switch, a subsidiary switch, a protective device in series with the main switch and connected in shunt around the subsidiary switch. an oplV erating handle, means operated by said liandle in moving from initial ott position to tirst close the subsidiary switch, and a spring interposed between the handle and the circuit closing element of the subsidiary l havev It' the cover is around the subsidiary switch, an operating handle, means operated by said handle in moving forward from initial ottl position to tirst close the subsidiary switch, and a spring interposed between the handle and the circuit closing element o' the subsidiary switch to enable the handle to continue its forward movement. a'lter vthe circuit closing element of the subsidiary switch has been closed.

3. A motor starter having a. main a subsidiary switch in series with the main switch, the subsidiary switch having a pair ot stationary contacts and a tlat circuit closing element adapted to move toward and Ytrom the terminals in a direction approximately normal to the surt'ace of the circuit closing element, a protective device in series with the main switch and connected in shunt around the subsidiary switch, an operating handle, means operated by said handle in moving forward from initial,` oil'` position.A

to iirst move the circuit closing element of the subsidiary switch into engagement with its cooperating terminals, and a spring ins tei-posed between the handle and the circuit closing element of the subsidiary switch to venable the handle to continue its forward movement atter the circuit closing element ot' the subsidiary switch has been brought into engagement with its cooperating terminals.

l. ln a motor starter, the combination of a -inain switch, a subsidiary switch, an

operated by the handle, whereby the iiiovements of said switches are independent to a limited extent, but interdependent as a whole.

5. 'ln a motor starter, the combination of a main switch, a subsidiary switch, a bail tor operating the subsidiary switch, a s econd bail for operating the main switch, said bail being independently. movable, one of said bails beine adaptedto actuate the other,

and an operating handle adapted to operate the bail-actuating bail.

6. In a motor starter, the combination of a main switch, a subsidiary switch, an operating handle, a bail for operating the subsidiary switch, a bail for operating the main switch, said bails being independently movable and one of them being operated by llO the handle, the other of said nails being` adaptedto be operated by the bail which is operated by the handle, there being lost motion between the main switch and the i bail which operates it.

T. A motor starter having a rotatable handle, a running switch having a circuit closing element rotatable about the reduced axis of the handle and actuate by the handle, and a starting switch having a circuit closing element rotatable about an independent axis, the circuit closing element of the running switch being adapted to engage the circuit closing element of the startlng switch at a point at least halfway distant from the axis of the startin switch to thereby increase the leverage o the action.

8. A motor starter having a rotatable handle, la-running switch having a circuit closing element rotatable about the reduced axis of the handle and actuate by the handle, and a starting switch having a circuit closing element rotatable about an independent axis, the circuit closing element of the running switch being adapted to engage the circuit closing element of the startlng switch at a point at least halfway distant from the axis of the starting switch to thereby'increase the leverage of the action, and the int of engagement on the circuit closing e ement of the running switch being nearer to the axis thereof than is the handle.

In witness whereof, I have hereunto subscribed m name. l,

HERLON L. VAN VALKENBURG.

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