USRE14539E - By the - Google Patents

Description

s. H. KEEFER. micn.r PHLES8EMENTPG0ND COMPANY. ASSIGNgE. SYSTEM or Moms coNTnoL. APPLICATION FlLEDv OCT. I9. l91l6. 1

2 SHEETS-SHEEI y2.

Reissued im; 22,. 1918.

lalmlwll. .3

LIIIIII E11 xr. 2 i MFTTURN'EV SAMUEL n.

ASSIGNEE, NILES-BEMENT-EOND COMPANY,

A ,CQRPORATION F NEW JERSEY.

KEEEEE, nEcEAsEn, LATE or PLAINEIELE, NEW JERSEY, AEr THE OE JERSEY CITY, JERSEY,

SYSTEM or MOTOR eoNTEoE.

14,539.- Y Original No. 1,156,484, dated October 12,

reissue ledctober 19, 1916.

1915, Serial No. 754,753, tiled March 17, 1913. .epplication for Serial No. 126,633.

DIVISION A.

To all whom it may concern:

Be it known that SAMUEL H. KEEFEInr citizenof the United States, re-

siding in Plainfield, Union county, New Jersey, but now deceased, did'during his lifetime invent 'certain Improvements in Systems of Motor Control, of which the following is a specification.

This invention relates to a system 0f motor control, and with regard to certain more specific features, to apparatus designed for controlling the operation 'of electrically driven machine tools such a's planers.

The objects of the invention are, to provide a portable device of simple construction for "stopping 'the motor at any time from any part of the apparatus; to provide an inexpensive, simpleand durable switch adapted to make one or another of several sets of connections and substantially safe against an accidental shifting of its movable member from any cause whatever; to provide means whereby the reversing, acceleratng and deceleratingof a motor may be reac ily, effectively. and reliably controlled from a portable switch tothe exclusion, for the Vtime being, lly conformerly a of the means norma trollingr these operations; and to apply to a system automatically braking and reversing a motor, a switching device which may be carried to any' part'of the machine and there manipulated to control the operation of the entire system.

Other objects will be in part obvious in part pointed out hercinafter.

The invention accordingly consists 'in the features f construction, combinations of elements and arrangement of parts which will be exemplified in the construction hereinafter set forth, and the scope of the application of which will be indicated in the following claims.

1n the accompanying* drawings, in which are illustrated one ormore of various possible embodiments of the several features of the invention, Figure 1 is a wiring diagram of. a system of motor control operating in accordance with the present invention; Fig.

and

Q is an elevation, partly in section, of a preferred form of pendant or master there is represented switch; and Fig.' 3 is a sectional view on the line 3-3, Fig. 2.

Similar reference characters refer to similar parts throue'hout the several views of the drawings.

Referring now to Fig. 1 of the drawings, a motor comprising the armature 1, shunt lield winding 2 and interpole winding 3, the connections of these 'several parts being made or broken in vari# ous ways by means of the'service controller hereinafter described in detail, For controlling theseveral operations of the motor,

`Specification of Rc'ssued Letters Patent.. Reiguigd 00h, 2.2, 19181, l

there is provided a body of resistance It adapted to be inserted at` times in series with the armature 1, and two sections otresistance. 5, 5, through which, at predetermined times, the current to the shunt field winding Q'flows. For governing the amount of resistance 5, 5 in circuit with the shunt field, there are provided two pivoted or otherwise movable contact devices 8, 9, of any suitable construction. Y

Coming now to the service controller, which makes and breaks, at the proper-tinies, the several connections betweenl the'parts enun'ierated above, there are provided four solenoid switching devices 10. 11, 12 and 13, the first of which comprises a winding 14, a movable core 15,- a lower contactl engaged by said core'whenthe winding 1l is denergized, and an upper contact 17 so by the core located as to be engaged when said windingr 1.4 is energized'. ln addition, the lower contact 16 is so supported by any suitable by the core 15,'itis forced into engagement with an auxiliary Contact 18. from which, however, the lower Contact 1G frees itself when the core 15 rises. Similarly the sceond switch 11 comprises a. winding 19, a core E20, a rlower contact 21 engaged by said core when it is in its ylowered position, and an upper contact 22 electrically connectedV with the core when the windingi 19 is energized soas to lift the core from the positionrillustrated in the dra-wings. A. third switch 12 has a winding` 23, a core Q4, a lower contact 25. and. an upper contact 2G all dcsignedto cooperate as described in ,connection with means that when engaged the first switch l1. It is, however, to be noted thatthe two cores and 24 have,

`. ment being frat their lower ends, contacts, respectively which engage the lower contacts" 2l and 25, While being insu *lated from the respective e them. The fourth switch 13, like the first4 indicatedy at 27 and 28,

cores which carry7 lower contact 31, an upper vcontact 32, and an auxiliary vlower contact 33, the arrangesuch that the core 30 in its lower osition no t `only engages the contact 31, ut causes the latter to engage at that time '.the'auxiliarycontact 33. When the core 30 gaged fromthe lower contact 31 by suitable to extinguish any is raised the auxiliary contact 33 is disen- Inechanism corresponding to that used in connection with the first switch 10.` The first andsecond switches l() and 11 have in common a blow-out magnet comprising a .winding 34 and a fixed core 35 so placed as arc yforming between the upper' or lower setsof contactsof these two switches. Similarly the thirdy and fourth switches 1x2-and 13 have a common blow-out magnet comprising a fixed core 36, and

a winding37 likewise placed to extinguish arcs formed at any of the contacts ot the switches l2 and 13. `ltlovably mounted, ad`

jacent and partly within the lower end of the fixed core 351of the first blow-out magnet is a contact 38 ada there being a body` of magnetic n'laterial connected to the movablecontact 38 in such a Way `that when the winding 34 vis sutliciently energized the contact`38 is drawn upward out of engagement with the 'fixed i Similarly the blow-out magl v the latter whenever the winding 37 of said magnet is sufciently energized. It will be `noted that the winding `switchll has in series with it resistance 42, and that the series-circuit con- 19.' of the second a body` of taining the winding'l), and the resistance 42is connected in parallel withthe winding l23 of the thirdswitch 12.

For controllingthe operation ofthe four automatic switches heretofore described, there is and a master switch44, of Lwhich the first preferably comprises a rotatable drumV 45 carrying two elongatedcontacts 46 and 47.

`Of these'the `contact 47 is designed to con-A nect together eithertlie contacts 48 and 49, or two other contacts. 50 and 51, While the second elongated contact g46 is capable of connecting together either the 50 andy 51 or the contacts 52 master switch 44, shown more two contacts and 53. The

`in detail.

Figs. 2 and 3, comprises,n the illustrated switchfl0, has a winding 29,a core 30, a"

`head 58 through which ted to coperate inits 4lowered position with ay fixed contact 39, jconnects the contacts 'movement of the provided a suitable pilot switch 43,

embodiment of the cylinder .54, with `insulating material'A 55 and. having mounted concentrically within it a `tube 56, also of insulating material and spaced away from the inner wall of said cylinder as indicated in Fig. V2. One vend of the cylindrical casing .54 yhas an outlet 57 curved to prevent injury toa cable (not shown) made upV of' the electrical conductorsentering the same, and its opposite end is provided with a asses a longitudinally movable and rotata ably of. insulating material and having an operating handle 60 of suitable shape. The inner end 6l of this rod 59 is uidedin a suitably formed recess 62 in a p ug or head 63 in that `end of the tube 56 a jacent the outlet 57, and it carries` two contacts 64 and V65,. the'iirst of which is preferably in the invention,` aupipe or preferably ofmetal and lined le rod59, prefer`- form' of a ring so placed as `to be capable of electrically'connecting two relatively lixed contacts 66 and 67 when the rod 59 is in itsL outer position. These two 'contacts 66 and 67, as well as three other'pairs of contacts 68, 69, 70, 7l,` 72 and 73, project through the walls of'. the insulating tube 56 and ex tend for a tube. tion 74 so located asto be capable of electrically connecting the fixed contacts 68 and 69`at the same time that the first ring 64 has a portion 7 5 extending longitudinally of the rod 59 so as to be capable of engagin;L with and electrically connecting either the contacts 71 and 73 0r the contacts 70 and 7 2 when the rod 59 is pushed inwardly to a; suflicient extent to its position vand is then, rotated one wayor the other through an angleof about ".L For the purpose'ot guiding and limiting the a projecting pin 76 designed to slide withina` slot 77r in aL head 78 in thatend of the sui-table distance insideof the The contact 65comprises a ring por- 66 and67 and it also i neutral or open-circuit rod 59', it is provided with tube 56 adjacent thehead 58; 'the slot 77 I comprising alongitudinal portion 79 and two portions 80, 81 extending in opposite" `directions from the inner end-of the longitudinal portion 79 forabout one-fourth the way around the head 78, whereby/it is possible to turn the rod 59 through an angle'of 900 either way from the neutral position, or tomove the `rod 59 from said position, vthe respective paths of' movement being guided and limited by the respective portions 80, 8179ot the slot 77.l Current from any suitable source of'supply Tis delivered to the above-desc`ribed sys-` tern of apparatusthrough a; pair ofinains 82 longitudinally outward j and 83, Fig. il, connectedv to a manually or automatically operated circuit-breaking device, illustrated conventionally at `84, and across the mains 82 and 83 on the motor side, of the circuit-breaking device 84 is prefer-` ably connected a'body of choking resistance 85.

In view of the'clear showing of the drawings, it is considered unnecessary to describe, in detail the eonnections'between the various pieces ofapparatus shown. Accordingly, the sequence of operations occurring when the pilot switch 43 and the master switch 44 are in vvarious combinations of positions will be next considered.

Assuming that the pilot switch 43 has its movable member 45 so turned that the elongated contact 46 thereon connects the contacts 50 and 51 and the elongated.V contacts 47 similarly connects the contact-s 48 and 49, current will Ifiow from the supply conductor 82 to the contact 68 of the master switch 44, through the contacts and 69 thereof, 'thence through the 'contacts 49, 47, 48 of the pilot switch 43, winding`14 of the first switch 10, and thence through the'contaets 40 and 41 to the second supply main 83. It will be'noted that previous to the operation of thepilot switch 43 from its neutral or open-circuit position, illustrated in Fig. 1, the closure of the circuit-breaking device 84 permits the shunt field winding 2 of the motor toy be energized, since current flows from jthe supply main 82 tosaid field winding 2, thence through contacts 28, 25 of the switch 12, and thence to the second supply main 83. As a result of the energization of the first switch windi'ng14, thecore 15 rises into engagement with the upper Contact 17 and the motor starts by virtue of thc current which flows from the suppl-y main 82 to the upper contact -17 and' core 15 of the first switch, thence through all of the series armature resistance 4, interpole winding 3, motor armature 1, core 30 of the fourth switch 13, lower Contact 31, winding 34 of the blow-out magnet adjacent the first andv second switches 10 and 11, and thence to thc second current supply main 83.

The rising of the core 15 of the first switch 10 permits current to flow y from the supply main 82 through the upper contact 17 and core 15 of the first switch 10, to theI windings 19 and 23 of the second and third switches 11 and 12, respectively, which windings, as beforenoted, are connected in parallel, and from these windings the current then flows through the pilot- switch contacts 50, 46 and 51, thende through the master switch contacts` 64 and 66, to the core 30 of the fourth switch 13, lower contact 31 thereof, blow-out winding`34 and so to the second supply main 83. .As a consequence` the core 24 of the third, switch 12 rises and shortly thereafter the core 2O of thc'second switch 11 is `likewise drawn up into engagement with its upper contact 22, the difference in the time of action of these two switches being duc toY the retarding effect tacts 28 and 2,5

of the body of resistance 42 in series with the winding 19 of the second switch 11. The rising of thel c'ore 24 of the third switch 12 short-circuits a 'portionof 'the series armature resistance 4, causing the motor to speed up, and the engagement of the core 2() of the second switch 11 with its upper'contact 22` causes thesho'rtscircniting of the balance of said armature resistanceV 4. 1t is noted, however, that the rising of the third switch 12 .separates the lower conthereof, thus removing the short-circuit` around a variable portion of the field resistance 5, so that even before thev rst half ofthearmature resistance 4 is cut ont, the motor` is speeded up by the weakening of its shunt field; After this first. half of the armature resistance 4 has been short-cireuited, the rising of the core 2O of the second switch 11 by removing the last part of the armature resistance 4 permits the direct connection of the motor armature 1 across the mains 82, 83, so that by the abovedescribed series of operations the motor is graduallyv accelerated to full speed.

The moving of the member 45 of the pilot switch to its olf .position and then to its reversing position, in the first instance causes the short-circuiting of the motor armature and the s'o-called dynamic braking of the motor. The short circuit current Hows from the armature through the interpole winding 3, the resistance 4, the core 15, the lower contact 16, the coil 37 the coil 34, the lower contact 31, the core 0 and back to the arma' ture. So long as an appreciablel amount of current flows in this short circuit the two contacts 38 and 4() are held elevated and out of engagement respectively with the contacts 39 and 41. So long as these contacts are separated, it is `impossible to close the energizing circuit for either of the magnets 10 or 13*A Preferably two high resistances 6 and 7 are connected' respectively between the. two contacts 38l and 39 and the two contacts 4f) and 41. These resistances are `such that lthey do not permit sutiicient currentto flow to energizethc coils of the magnets 10 and 13, but they do` serve to prevent any serious art-ing between the contacts 38 vand 39 and the contacts 40 and 41. 'After the motor speed has decreased to the desired, extent, the motor is automatically started in the rcverse direction, as may be noted by tracing the various circuits. For the reverse direction use is made ofthe magnet 13 instead of the vmagnet 10, but the connections are otherwise similar to those already described.

lf while vthe movable member 45 of the pilot switch '43 is in-its off position (shown in Fig. 1) themovable member 5 9 of the master switch 44 bepushed inwardly from its outer position (shown in Fig. 1), the electrical connection between the contacts 66 and 67 as Well as between' the contacts 68 the core 24 of icc A and 69 isf intim.VV if the rod 59 be niet rotated through', an angle of 90, the elon gated portion 75 of the movable contact 6.5- wil'l be brought into engagement with the fixed contacts'71 and 73, for example, Witlw. the resultthat current will How from thesupply "main 82 to said `iixed contact 7l, thence through the elongatedr Contact 75 and fixed contact 7 3, through' the winding 14 of the iirst switch 10, to the second supply `main 83. As a consequence, the core is moved to its upper position of engagement with the upper contact 17 and current flows through ythemotor armature 1 as above de- `switch 43.A Itis thus possible to Vmotor to turn at itsI lowest speed independ-f ently of the pilot switch 43 by the above-i scribed, although in this `case there is no speeding up ofthe motor by reason of thek cutting out of thear1nature resistance 4 because the circuit including the windings 19 and 23 of the accelerating switches 11 and 12 is open at the contacts 66, 67 of the pilot cause thel described manipulation of the operating handle of the master switch 44, and if said handle b e soturned that ,able contact 74 connects the. two xed convtacts 70 and 72 instead of the two'fixed con;

tacts 71 and 73,`then the Winding 29. of the fourth switch 13 instead of the winding 14 of the first switch 10 is energized, and current is supplied to the motor armature in a direction the reverse of that previously" noted, thus causing a reversal of the direcltion of rotation of the motor. however, the motor is necessarily operated only at its lowest speed, as lthe solenoids 19 and 23 ofthe accelerating switches 11 and 12 are open-circuited previous case.

It 'will be lnoted that the pilotv switch' 43 cannot ycause theoperation of the apparatus while the operating member 59 of lthc master switch 44 isdn its inner or open-circuit `position, for the reason that two of the circuits controlling the reversing and accelerating switches, 'which pass through said pllot switch, are broken aty the contacts 66, 67 and 68, 69 in the masterswitch. o

If, while the apparatus is operating with thepilot switch 43 in either of its two on pos1tion`s, ther movable member 59 of the master switch 44 be pushed lnwardly, the

actuating current is out oil' fromA the service controller, Whose cores at .once drop, thus causing the motor to be quicklybrought to a stopy byjvirtue of the dynamic current flowing throughthe short-circuited Aarma- -ture 1.

The above-described arrangement of apparatus is particularly adapted for use with machine tools, such as planers, and when so used ,the pilotswitch 43 would Vbe manipu- `lated by hand or automatically to cause the rotation ofthe 'motor first in4 one directionthe machine and there tion regardless of the pllot'svvitch` 43happens to be.

the elongated mov'- 1 As before,`

Y in combination y'at 66, 67, as in the 'automatic' means,

and thenin the other, suitable mechanical connections being provided between the Inotor and the reciprocating table ofthe .planer so that the rotation ofthe motor .inthe tv vo directions causes the reciprocation of` the table. The master switch 44 'is peculiarly' well` adapted to hang as a pendant at any; desired part of the apparatus and tube carried at will by an operator to'anypart 'of l manipulated to stop the motor or to run itsloWly in either direcposition inwhich th thus be clearthat the several ob- ]ects of, the im ention are secured and other advantageous ends attained.

Asmany changes could be made in the above `construction and many apparently Widely different embodin'lents of this inven tion could be made without departing from the 'scope thereof, it is intended that all lnatter contained in the above description or shown in the `accompanying drawings shall be interpreted `as'illustrative and not in a` limiting sense.

It is also to be understoodthat the lain guage used in the following claims is in tended to Coverall of the generic and specific fea-tures of theinvention herein described and all statementsof the scope of the invention, which, as, be said to fall therebetween.

The electrical apparatus herein disclosed, including the 1notor,the switches Vand the various connections and operating devices therefor, is not in the present case claimed with a planer or other machine comprising a reciprocating table, such It will in application Serial Number 126,634 led lill) on even date herewith andy constituting Division B of thisr application for reissue.

Having'described the invention, what is claimed as neur and desired to be secured by Letters Patent is:

'L Apparatus ofthe character described' comprising, in combination, a motor, auto.- matic means comprising'devices for controlu ling the direction of rotation of said'motor,

and other devices for controlling the acceleration of said motor, means for governing the operation of all of said devices of said a second means for governing independently of and to the excluv sion of `said first named governing means theoperation of those devices of said auto matic'means that'control the direction of rotation of said motor fwhile rendering inoperative those devices of control the acceleration of said moto-r.

2.' Apparatus of the character described comprising;- in combination, means adapted to influence the operation of a motor in two directions and atl a' plurality of'y speeds, means adapted to energize said Iirst means said means that to rotate the motor in either direction at onev otsaid speeds, and means adapted to energize said irst means to rotate the motor in either direction at another speed.v and to render the .said first means inoperative.

3. Apparatusof the character described comprising, in combination, a motor, a pilot switch, a switching device controlled thereby for starting and accelerating the motor, and a master switch for starting or stopping the motor independently of the pilot switch, a circuit of the pilot switch extending through the master switch so as to be broken when said master switch is operated.

4. Apparatus of the character described comprising, in combination, a motor, a pilot l switch, switching devices governed thereby I switch without permitting operation of thefor controlling the starting and accelerating of the motorrespectively,` and a master switch adapted to cause operation of the starting device independently of the pilot accelerating device. i 4

5. Apparatus-of the character described comprising, in combination,

switch, a starting device and an accelerating device governed by said pilot switch, and' a master switch connected andadapted to govern the operation. of the starting device independently of the pilot switch, the controlling circuit of the accelerating device passing through the pilot switch and the master switch and being broken by operation of said master switch.

6. Apparatus of he character described comprising, in combination, a motor, a pilot switch, switching devices connected to form a reversing switch and an accelerating switch all governed by said pilot switch, and a master switch connected to govern operation of the reversing switch independently of the pilot switch, the controlling circuit of the accelerating switch passing through the pilot switch and the master switch so as to be broken' by operation of said master switc 7. Apparatus of the character described comprising, in combination, a motor,.a pilot switch, a starting switch and an accelerating Coplel of thi! patent may be obtained for nv cents each, by addressing the Wuhfngton, D. 0.

a motor, a pilot.'

and a master switch connecte-d to govern the starting switch independently of the pilot switch, the controlling circuits of the reversing switch and of the accelerating switch both passing through the master switch so as to be broken when said latter operated to cause operation of the reversing switch. y

9. A control system comprising an electric motor, means for controlling the motor circuits, and a master switch for governing the control-,means and for establishing a dynamic braking. circuit whenever it is adju'sted to reverse the motor,` said master switch being operatively 'connected to the motor, and a manually operated master switch adapted to intervene `and govern the control means independently of the motoroperated master switch.

10. In a motor-control system, the combination with an electric motor and reversing switches a master switch actuated by said motor for controlling said reversing switches and a manually operable switch in series with the master switch for rendering the latter ineffective and for controlling` said reversing switches independently of said master switch.

In testimony whereof, the Ninns-BEMENT- PONDI COMPANY causes its corporate seal to be hereto attached and its signature to be hereto affixed by its proper officer.

[1.. 8.] N lLES-BEMENT-POND C OMliiNY,

By FAY INGALLS,

Secretary.

Commissioner of Patents,

switch isy

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