USRE18238E

USRE18238E - whittingham

Info

Publication number: USRE18238E
Authority: US
Publication date: 1931-10-27

Description

1931- G. H. WHITTINGHAM FRICTION SWITCH MECHANISM Original Filed April 25, 1930 2 Sheets-Sheet 1 L l x 4 Oct. 27, 1931. G WH|TT|NGHAM Re. 18,238

FRICTION SWITCH MECHANISM Original Filed April 25, 1930 2 Sheets-Sheet: 2

gwue'ntoz W al ke 1140,64

Reissued Oct. 27, 1931 K UNITED STATES PAT ENT OFFICE GEORGE H. WHITTING-RAM, OI BALTIMORE, MKRYLRND, ESSIGNOR TO MONITOR GON- TROLLER COMPANY, OF BALTIMORE, MARYLAND, A"GORPIMTION OF MARYLAND rnxc'rmn swnrcn mammal Original No. 1,806,377, dated May 19, 1931, Serial No. 447,317, filed April 25, 1930. Application for reissue filed July 14, 1931.

This invention relates to circuit-controlling mechanism designed to control circuits in predetermined times and in predetermined order after the performance of an initial operation which starts the mechanism into operation. In the control of electric motors, where it is desired to operaterelays or contactors in predetermined times and order, delay in the actuation of the switches controlling the tOl'lbflttOl'S or relays may be obta ned. in various ways, as by the use of thern'iostats, but practical difficulties arise in the use of such devices Where long periods of delay are required in the actuation of the switches. The purpose of thepresent invention is to provide a circuit-controlling mei'hanism in which a. plurality of switches may be actuated in any desired order and reset siimiltaneously, and in which a very Lon delay in actuating the switches is readily obtained.

In carrying out the invention, I provide a shaft which is rotated at a very slow and constnnt speed; a series of switch members mounted upon a stationary support beside the sha ft, a plurality of movable circuit-cont rolling members loosely 'ournaled .on the shaft and having parts-a apted to engage the stationary members, these circuit-controlling members being biased away from the stationary members and adapted to rock freely on the shaft into engagement with a fixed stop; friction devices of conducting material rotatable with the shaft and ary, ranged on opposite sides of the movable members, and means for clam. ing said devices against the movable mem ers to cause the latter to move with the shaft in the direction lo engage the stationary switch members. Finch circuit-controlling member has an arm which is adjustable toward and from the opposing stationary switch member, to vary theorder in which the several switches will be actuated and the time of actuation. The shaft rotates very slowly and at a. known speed. that by adjusting the arm on the movable member the time of its engagement with the stationary member may be accuratelv pro-set. As each circuit-controlling member engages a. stationary member the Serial No. 5503.806.

former member stops, while the friction devices which engage it continue in operation. Whenit is desired to reset the circuibcontrollinmmembers, the'friction devices are released rpm the circuibcontrolling membflrs and-the'latter then rock on the shaft to their initial positions againsta fixed stop.

In the accompanying drawings,

Fig.' l is a front elevation of the mechanism;

Fig; 2 is a section on the line 22 of Fig. 3;

Fig; 3 is a front elevation of the ap aratus, the shaft which operates, the switc es and the mechanism thereon being shown in vertical section; i

Fig. 4is a top plan view of the apparatus with the motor removed, and,

Fig. 5 is a side elevation of one of the movable switch members, its contact arm bein removed.

lteferring to the drawings, 1 indicates a. suitable base of insulating material to which are secured forwardly rojectingmetal bars land '3, spaced apart" rom one another and forming supports for the workingjparts of A tubularshaft 4 extends the apparatils. horizontally through these bars and is journaled therein, afnd uponthis shaft is mounted a worm wheel '5', which is geared to a small electric motor 6 by reduction earing which causes the worm wheel and siaft 4 to turn at a very low speed when the motor is in operation. The motor is preferably a shuntwound motor which operates at constant speed. .A number of friction disks a, @10 andaf are mounted upon the'shaft 4, so as to turn witli'it, but these disks are movablerelatively to one another longitudinally of the shaft. The friction disks are composed of electrically conductive material, preferably carbon-graphite composition, molded into the desired shape. The shaftis provided with a longitudinal slot 7, which serves as a keyway into which keys 8, in the friction disks, extend. The key 8-, in the disk at, extends completely through the slot and projects slightly into the bore of the shaft, While the keys on the other disks areshorter and do not extend into the bore. The webs 9 of the frifitlon'disks are formed with central openings sufficiently large in diameter to permit the disks to move freely longitudinally of the shaft and to rock laterally to a slight extent, and to facilitate this latter movement the webs are beveled inwardly toward the openings, "as indicated at 9. Each friction disk has oppositely projecting annular flanges 10. One side of the disk or. rests against the side of the gear 5, and a pin 5 preferably extends from the gear into a socket in the disk near its periphery, as shown in Fig. 3, to assist in driving the disk. 7

Between the friction disks are mounted circuit-controlling members I), b and 6, each comprising a metal plate 11., having a central opening 12, through which the tubular shaft extends. The plates are in the form of disks which, for about one-half of their circumferential lengths, project radially beyond the peripheries of the friction disks, and the projecting portion of each plate has a flange 13 which projects at opposite sides of the plate. This flange, on each plate, forms a support and guide for an adjustable contact arm. A. Ushaped clamp or yoke 14 fits around the flange of the member 6 and a'contact arm 15 has a short right-angled portion a', which is clamped against the periphery of the flange by a set screw 16 at the center of the clamp or yoke. The contact arm 15 extends in an approximately radial direction from the flange and is adapted to engage a stationary contact member a, which is mounted upon the switchboard. Similarly, contact

arms

15 and 15" are adjustably secured to the flanges of the members I) and b by clamps 14 and 14', respectively and these members 15* and 15 are adapted to engage stationary contacts c' and 0 respectively. A weight 17 projects radially from the member b at one end of its flange, and similarly arranged

weights

17 and 17" project from the members b and 5 These weights tend to rock the plates to which they are attached so as to hold the contact arms out of engagement with the stationary contact members, and normally these weights rest against a strip of insulating material 1.8 which is supported by a bracket 19 connected to the insulating base 1. The edge of the strip 18, which the weights rest against, is parallel with the axis of the shaft 4;.

A rod 20 extends longitudinally through theshaft 4. and is provided with a head 20 at one end, and between said head and the friction disk a is a metal clamping disk 21 of the same diameter as the disk (1 The rod 20 fits freely in the bore of the shaft 4 and is movable longitudinally therein so that if the rod 20 is moved to the right in Fig. 1, it will cause the clamping disk 21 to bear against the friction disks a and the several friction disks will be clamped against the plates of the movable circuit-controlling members b, b and 77 A magnet d is susin which an armature 23 is pivotally mount- This armature has an arm 24.- which projects upwardly and has an opening through which 'the right hand end portion of the shaft 20 extends. The shaft 20 has a shoal der 2(7) and when the magnet is de-energized and its armature is away from its pole-piece. the arm 24presscs the washer against the shoulder and holds the rod in position to release the friction disks, as shown in Figs. 1 and 3. The armature is normally held in this position by a spring 25 which is coiled upon a stud 26, the latter projecting horizontally from the arm 22 on the support 22 through an opening in the arm 24. The arm 24 con stitutes a lever for moving the shaft 20. On this lever, midway between the shaft 20 and the spring 25, a projection 27 is provided and this forms a fulcrum for another lever 28, the lower end of which is interposed between the spring 25 and the lever 24. The upper end of the lever 28 has an opening through which the'shaft 20 extends and this end of the lever bears against a Washer 29 which is held in place by a cotter pin 30, passing through the shaft 30.

When the armature 23 is lifted by the magnet. the lever 24 swings away from the sh0ulder20, and pressure is applied to the central part of the lever 28 at the fulcrum 27. As the spring 25 bears against the lower end of the lever 28. the upper end of said lever applies a yielding pressure to the rod 20, tending to force it to the right to clamp the friction disks against the plates of the movable circuit-controlling members. when the armature 23 drops, the lever 24 swings to the left, releasing the pressure at the center of the lever 28, and the lever 24, hearing against the shoulder 21, moves the rod 20 to. the left, releasing the pressure of the fric-. tion disks against the plates of the movable cirouit controlling members.

In order to avoid any adhesion of the friction disks to the plates when the rod is moved to unclamp the disks, I provide a collar 20* on the'rod 20 which strikes the long tooth or key 8 in the friction disk 0;, when the rod 20 is moved to the left by the lever 24, and the jar given to the disk (1 is imparted to the other disks and the plates, insuring their immediate separation.

A conductor 31 is shown connected to the supporting bar 3 and all of the movable parts of the apparatus are electrically connected to this support and wire 31.

Conductors

32, 33 and 35! are shown connected to the stationary switch members 0, c and 6 respectively. The coil of the magnet may be connected to the current source in any desired way, according to the use which is to be made of the apparatus.

. The shaft sitar-main the-clo kwise dimes time when" niolwedcfrmrr its'right hande while she weights onzthe wearable circuitcontrolliaag members tend to rock :said memhers on theshaft away from the stationary switch members. Normally, the movable members are held out of engagement with the stationary members by the weights on the former, which rest against the stop 18. The motor may runconstantly, or it may be switched into and out of circuit, as desired, according to the purpose forgwhioli the appanatus is used. The amnesia, and Vii-Rube set on the movablemembers atsmy desired distance from the stationary members according to the delay desired in ac tuatisng the switches. Assuming the motor to be running and the arms to be set on the movable members as shown in Figs. 1 and 2, if the magnet d is energized, it will attract its armature 22 andtbe lever 24, connected to tbaarmature, will press the lever 28 to the right. and this latter letter will move the rod 29 in the dinection to draw themetal .disk' 21 against the adjacent friction disk 0, and canse the movable members 6, b and b to be clamped between the friction disks a, a, a and of. As the friction disks slowly rotate, the

arms

15, 15" and 15 will engage the stationary switch members 0, a and respectimei in saccessiom As each arm engages a; stationary switch membenthe metal plate to whichmhe arm is eonneetedstops while the friction diskson either side; of the plate continue to rotate; When rt-is desired, to reset the switches the circuit-of the magnet d is broken. and the armature of the magnet drops, causing the lever 24 to be moved by the spring against the shoulder on the 40 rod 20, and the rod is thereby moved to the left. When the rod 20 is moved to the left, the pressure of the clamping disk 21 against the friction disk at is relieved and the collar or tappet 20 jars the disks and plates loose.

When this occurs, the weights on the movable circuitfcontnolling members immediate ly rock said members about the shaft until the weights on said members engage the stop 18. The contact arms on said members are thus returned to their original pro-set positimes.

As the friction disks, of carbon graphite composition, are electrically conductive and mounted upon a metal shaft which is con- 66 nestedtbrongh its bearings to the current source, good electrical contact is made through the frictiondisks to the circuit-controlling members when they are clamped between the friction disks. Friction disks '00 of impregnated woodmight be substituted for the carbon-graphite disks, but in that event it would be necessary to provide flexibleolectrical connections to the circuit-controlling members if the latter are to serve as $6 switch members.

1. In an trieaslinzsvitehslefi am a a shafts m ans f r rotating the shaf 1 s .tionary switch-member, a movable circuitcontrolling member comprising a metal body jcurnaled upon the shaft and having a part adapted to engage said stationary memben said movable member biased away from said stationary member, friction devices on opposite sides of said body, said devices secured to the shaft so as to rotate therewith and being relatively movable longitudinally of the shaft, "and means for clamping said devices frictionally against said body to cause rotation of the movable mom er into engagement with the stationary member.

1n. electric slip-switch mechanism, a shaft, means for rotating theshaft, a stationary switch-member, a movable circuit- .controlling member comprising a metal body iournaled upon the shaft and ha ing a p rt adapted to wg ge i stationary member said movable member being biased away from said stationary member, friction devices of carbon-graphite composition on opposite sides of said body, said devices secured to the shaft so as to rotate therewith and being relatively movable longitudinally of the shaft, and means for clamping said devices frictionally against said body to cause rotation of the-movable member into gag ment with the stat o a member 11 an electric slip-switch mechanism, a shaft, means for rotating the shaft, a plarality of stationary switch members; a plu rality of movable circuit-controlling 'members each comprising a metal body journaled upon the shaft and having a part adapted to engage one of said stationary members, said movable members being biased away from said stationary members, friction devices on opposite sides of the several bodies, said devices secnredto the shaft so as to rotate therewith and being relatively movable longitudinally of the shaft, and means for clamping said devices frictionally against said bodies to cause rotation of the movable members into engagement with the stationary members.

4. In an electric slip-switoh mechanism, a shaft, means for rotating the shaft, a pluralit of stationary switch members, a plurality o movable circuitrcontrolling members each empl s ngametel body jou a ed upon each shaftand having a. part adapted to engage one ofsaid stationary members, said movable members being biasedawazy from said stationary members, friction devices of carbongraphite composition on opposite sides of the several bodies, said devices secured to the shaft so as to rotate therewith and being relatively movable longitudinally of the shaft, and means for clamping said devices fric tionally against said bodies to-cause rotation of the movable membersinto engagement with the stationary members.

5. In an electric slip-switch mechanism, a

shaft, means for rotating the shaft, a plu rality of stationary switch members, a pinrality of movable circuit-controlling' 'members each comprising a plate loosely journaled upon the shaft and having a part adapted to engage one of said stationary members, said movable members being biased away from said stationary members, a stop for liniiting the free rotation of the several plates, friction devices on opposite sides of the several plates, said devices secured to the shaft so as to rotate therewith and being relatively movable longitudinally of the shaft, and means for clamping said devices frictionaily against the plates to cause rotation of the movable members into engagement with the stationary members.

6. In an electric slip-switch mechanism, a shaft, means for rotating the shaft, a stationary switch member, a movable circuit-controlling member comprising a metal disk loosely journaled upon the shaft and an arm adjustable on said disk toward and from the stationary switch member, said movable member being biased away from the stationary member, friction devices on opposite sides of the metal disk, said friction devices secured to the shaft so as to rotate therewith and being relatively movable longitudinally of the shaft, and means for clamping said friction devices against the metal disk to cause rotation of the movable member into engagement with the stationary member.

7. In an electric slip-switch mechanism. a shaft, means for rotating the shaft, a stationary switch member, a movable circuit-controlling member comprising a metal disk loosely journaled upon the shaft and having a peripheral flange and a part adjustably mounted on said flange, a stop for limiting the free rotation of said metal disk, friction devices of carbon-graphite composition on opposite sides of themetal disk, said friction devices secured to the shaft so as to rotate therewith and being relatively movable longitudinally of the shaft, and means for clamping said friction devices against the metal disk to cause rotation of the movable'memher into engagement with the stationary member.

8. In an electric slip-switch mechanism, a shaft. means for rotating the shaft, a stationary switch member, a movable circuit-controlling member comprising a metal disk loosely journaled upon the shaft and having a part adapted to engage the stationary memher and a weighted arm, said arm tending to rock the movable member away from the stationary member, a stop adapted to be engaged by said arm to limit the free rotation of the metal disk, friction devices of carbon-graphits composition on opposite sides ofthe metal against the metal diskto cause rotation of the V.

movable member into engagement with the stationary member.

9. In an electric SIi sWitch'mechanism, a tubular shaft, means for rotating the shaft, a

stationary switch member, a movable circuitcontrolling member comprising a metal plate loosely journaled upon the shaft and having a part adapted to engage said stationary member, said movable member being biased away from said stationary member, a stop for limiting the free rotation of the plate, friction devices of carbo -graphite composition on opposite sides of the plate, said devices secured to the shaft so as to rotate therewith and being relatively movable longitudinally of the shaft, and means for clamping said friction devices against the plate comprising a rod extending through the bore of said shaft, a clamping disk mounted on said rod and adapted to engage one of the friction devices, an electromagnet, and means operated by the magnet for moving said rod end- Wise to cause the clamping disk to press the friction devices against the metal plate.

l0. In an electric slip-switch mechanism, a. a

shaft, means for rotating the shaft, a station'- ary switclrmember, a movable circuit controiling member comprising a metal body journaled upon the shaft and having a part adapted to engage said stationary member, said movable member being biased away from said statiouarymember, friction devices on opposite sides of said body, said devices secured to the shaft so as to rotate therewith and being relatively movable longitudinally of the shaft, means for clamping said devices against the plate and for releasing the devices, and means for jarring said devices and metal body when they have been released.

11. In an electric slip-switch mechanism, a

tubular shaft, means for rotating the shaft, a stationary switch-member, a movable circuit-controlling member comprising a metal body journaled upon the shaft and having a part adapted to engage said stationary member, said movable member being biased away from said stationary member, friction devices on opposite sides of said body, said devices secured to the shaft so as to rotate therewith and being relatively. movable longitudinally of the shaft, a rod extending through the bore of the shaft, a clamping disk on the rod adaptedto engage one of the friction devices, means for moving said rod to clamp and unclamp said devices, and

means on the rod for jarring said devices when therod is moved to. unclamp the disks.

12.. An electric slip-switch mechanism comprising a shaft,means for rotating the shaft, a stationary switch member, amovahlecirv cuit-controlling member journaled upon the shaft and biased away from said stationary member, friction devices carried by the shaft on opposite sides of the movable member and positively driven by the shaft, a stop for limitingthe movement of the latter member away from the stationary member and means for clamping said devices against the mov able member and for releasing said devices.

13. An electric slip-switch mechanism comprising a shaft, means for rotating the shaft, a stationary switch member, a movable circuit-controlling member journaled upon the shaft and biased away from said stationary member, a part adjustable on the movable member toward and from the stationary member, friction devices carried by the shaft on opposite sides of the movable member and positively driven by the shaft, a stop for limiting the movement of the latter member away from the stationary member, and means for clamping said devices against the movable member and for releasing said devices.

14. An electric slip-switch mechanism comprising a shaft, means for rotating the shaft, a plurality of stationary switch members, a plurality of movable circuit-controlling members journaled on the shaft and biased away from the stationary members, friction devices carried by the shaft on opposite sides of the several movable members and positively driven by the shaft, and means for clamping said devices against the movable members and for releasing said devices.

In testimony whereof I aflix my signature.

GEORGE H. WHITTINGHAM.

CERTIFICATE OF CORRECTION.

Reissue Patent No. 18,238. Granted October 27, 1931, to

GEORGE H. WHITTINGIIAM.

It is hereby certified that erro above numbered patent requiring co 4, for the word "each" with this correction the in the Patent Office.

Signed and sealed this 9th day of February, A. D. 1932.

r appears in the printed specification of the rrection as follows: Page 3, line 120, claim read the; and that the said Letters Patent should be read rein that the same may conform to the record of the case M. J. Moore. (Seal) Acting Commissioner of Patents.