US1592526A - Electric switch - Google Patents

Description

July 13,1926.

- c. L. HOPKINS ELECTRIC SWITCH Filed on. 18, 1919 4 Sheets-Sheet '1 July 13 1926. 1,592,526

0. L HOPKINS ELECTRIC SWITCH Filed Oct. 18, 191 9 4 Sheets-Sheet 2 fiver/for.-

' C. L. HOPKINS ELECTRIC SWITCH Filed Oct. 18, 1919 4 Sheets-Sheet 5 July 13 1926.

1,592,526 C. L. HOPKINS ELECTRIC SWITCH Filed Oct. 18, 9 4 Sheets-Sheet "4 2 M QWW v WI-@ 6.

Patented July 13,

UNITED STATES PATENT OFFICE.

CHARLES L. HOPKINS, or RIVER FOREST, ILLINOIS, Assreivon'ro Banner/Human H TRIO MANUFACTURING ILLINOIS.

COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION,OF

LECT IC SWITCH.

Application filed October 18, 1919. Serial No. 331,624.

breaks are made in the circuit substantiallysimultaneously,thereby dividing and decreasin the arcing effect, and consequently lessening the danger of injury to the switch, and other undesirable effects.

A further object of my invention is to provide an electric switch for use in an electrical receptacle, which will be simple in construction, and etlicient 'in use, and

cheap to manufacture. 1

Further objects will appear from the detaileddescription to vfollow and from the appended claims.

In the drawings, in which two embodiments of my invention are shown:

Fig. 1 is a plan view of a pull switch 90 socket embodying my invention;

Fig. 2 is a section on the line 22 of Fig. 1; i

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

Fig. l'is a section substantially on the line 4l-4 of'Fig. 1;

Fig. 5 is a section substantially on the line 55 of Fig. 2; I V

Fig. (Sis a section substantially onth'e line 6 7 of Fig. 1 looking to the left;

Fig. 7 is a section substantially on the line 6-71ot Fig. 1 looking to the right; j

Fig. 8 is a detail perspective view showing part of the switch frame;

Fig. 9 is a detail perspective view" showing a combined bearing and spring retaining member Fig. 10 is a. detail perspective view of:

one of the rotatably mounted switch contacts;

v Fig. 11 is a detail perspective view of of Fig. 12;

Fig. 14 is a section on. the. line 14-1 l of Fig-13; V

Fig. 15is a section substantially on the line 1515 of Fig. 12;

Fig. 16 is a section substantially on the line 16-17 of Fig. 12 looking to the left;

Fig. 17 is a section substantially on the "ing, repair, etc.

Fig. 13 is a section on theline13-13 line 16117 of Fig. 12 looking to the right;

Fig. 18 is a detail perspective viewof a fixed spring contact member forming part of the switch; 7 i i Fig. 19 isa detail perspective view showing a combined bearing and spring ,retaining member; and I I Fig. 20 is an exploded perspective view of certain'parts of theswitch. i 1

In order to give a general idea of the construction of. Figs. 1-11 inclusive, it is here stated-that my invention is here shown embodied in a pull switch socket, having shell and center contacts, 25 and 26 respectively, for engagement with an insertable 'de 1 vice of the Edison type and having wiring terminals 27 and 28 for connection with a pair of feed wires, (one of the wiring terminals 27jbeing connected directly with the threaded shell contact of the receptacle) and a pull switch mechanism having. two rotatably mounted contacts'29 and 30;(in sulated from each other in the off posi:

tion), one ofthese contacts 30 being electrically connected with the center contact, and the other contact 29 being electrically connected with the other wiring terminal 28, and a relatively stationary electrical conducting member '30 with which the two rotatable contacts 29 and 30 both inakecontact in their movement, and with'respect to which both of said contactsare movable out w of contact intlieir movement, whereby as ously. I p

The receptacle contacts, switch mechanism and Wiring terminals are all mounted on an insulating base 31. and this insulating base and parts carried thereby are housed in a sheet' metalcasing 32 having-a sheet metal'ca'p 33, whichcan be removed for. wirthe contacts are rotated, the circuit from the 'w1r1ng terminal to the center contact 15 brolc en at two points, substant ally snnultane The usual lining .34. of

above the insulating base 31 to prevent short cir'cuiting of the live parts carried by the insulating base.

v The wiring terminal 27 is electrically connected with the threaded shell contact 25 by means of a screw '36 (Figs. 1 and 3) the head of which engages the flange 87 of the threaded shell contact, and the upper end of which is threaded into the wiring terminal 27 The wiring terminal 28 is secured on the insulating base 31 by means of a screw 37 (Figs. 1 and The wiring terminals 27 and 28 are provided with the usual binding screws 38.

The pull switch mechanism comprises (in addition to the two separated rotatably mounted contacts 29 and the connecting member 30, previously referred to), a rotatably mounted insulating contact-carrier 39 to which the contacts 29 are secured, (the contact-carrier, together with the contacts carried thereby forming a commutator memher), an oscillatable operating member or switch-lever -10, which is operated to impart movement-to the co mnutator, ratchet mechanism 41 between the oscillatable lever 40 and the commutator for changing the oscillating movement of the switch lever 40 to av step by step. movement in the commutator, a pull chain 42 carried by a chain-rail 43 for operating the switch lever 40, and a coil tor sion spring a l for returning the switch lever 40, after it has been operated by the pullcliain A shaft i5 is secured to the contact-carrier 39. This shaft may be molded into, the contact-carrier if desired. One end of this shaft is rotatably mounted in a combined bearing and spring retaining member to which is adjustably secured in an opening l7 in a bracket d8. This bracket 4-8 is secured in place on the insulating base 31 by means of a screw 418, which screw also serves, to electrically connect this bracket 18 with the center contact 26. The contact 30 is electrio-ally connected with the shaft; (4:5 by means of an arm or connecting member 5,0, which e:-:tends inwardly from the contact, and surrounds the shaft i c, this shaft 4 43, being of conducting material, so that the contact 30 is always electrically connected with the center contact 26 through the screw 49, the bracket as, the shaft all), and the arm 50.

This arm 50 is also provided with ratchet teeth 51 which form part of the ratchet mechanism -11 between the switch leverl0. and the commutator, the switch lever 40 being provided with depressions 52 for cooperating with the ratchet teeth These. depressions 52' have sloping bottoms, which slope down from the surface of the lever 40, terminating against the shoulders 53, against which the free ends ot the ratchet members 51 engage when the switch lever 40 is rotated. These depressions 52 may be formed in the lever 10 in the operation of stamping, the lever 40 being made from sheet fibre, which is of such a nature that these depressions can be formed by stamping. The chain-rail i3 may be a sheet metal stamping, having a curved arcuate portion 54- in which the chain lies, and having a hook portion 55 for engagement with one of the balls of the chain 42, whereby the chain is secured to the chain-rail. The chain-rail is secured to the switch lever 0 by means of integral projections 57 (Figs. 2 and T) which extend through openings in the lever 40, the ends of these lugs being bent over to firmly secure the chain-rail in place.

One end of the torsion spring ell is secured to the switch lever it) as shown in Figs. 2 and l, the end of the spring engaging a lug 58, and the other end oil the spring is secured to a lug 59 (Figs. l and 9) formed integral with this bearing and spring securing member 4-6. For adjustably securing this bearing and spring member in the bracket 48, tor adjusting the tension of the torsion spring i i, the member is provided with a struck-up portion, or lug (50 (Figs. 2 and which struck-up portion can be made to engage in any one or three slots 61, extending outwardly from the opening i7 in the bracket l-S. (Fig. 8), the member 46 is provided with a slot 61 for engagement with a screw-driver, whereby the member L6 can be pushed inwardly and turned to the desired position, and then allowed to spring out again, (under the action of the spring a l) to cause the lug ($0 to again engage one of the slots (31. As previously stated, the purpose of this torsion spring ll is the return to. switch lever l0 after it has been operated by he pull chain 4L2. It also exerts endwise pressure to keep the ratchet members in engagement. Pulling down on the chain 42 revolves the commutator through the ratchet mechanism 41. After the chain has been pulled down, it is released, and the torsion spring l i returns the switch lever 40 and pull chain 42 to their original positions, the commutator, however, remaining stationary during this return movement, the ratchet mechanism all permitting this return movement of the switch lever elO without a corresponding movement of the commutator, 1 it The binding terminal 28 has a bracket portion 62 formed integral therewith, which has an opening which provides a bearing for one end of the commutator. The contact 29 is electrically connected with this bracket portion (32 by means of an arm (33 (Figs. 5 and 10) extending inwardly from the contact, this arm 63 being provided with a sleeve portion 6% which tits snugly in an opening in the bracket portion (32, and in which sleeve Get an extension 65 of the contactcarrier 39 fits snugly (Figs. 2 and 5). The contact 29 is thus always in electrical connection with the wiring terminal 28 thru the arm 63, sleeve portion 64 and bracket portion 62.

As previously described, the other rotatable contact 30 is always in electrical conrier.

. as will move the commutator degrees of movement.

nection with the center contact. In the off position o1 the switch, these two ro-' tary contacts 29 and 30 are insulated from each other, but in the on position of the switch they are electricallyconnected with each other through the connecting member 30. The circuit from the wiring terminal 28 to the center contact isthus made and broken at two, points simultaneously by mov- 30 can be moved into'and out of engagement therewith, by rotating the commutator. The contact carrier 39 'is provided with a centralflange p'ortion70, which forms an insulating barrier and serves to prevent short circuiting or arcing between the con tacts 29 and 30. "Each of the contacts 29 and 30 is spirally curved to conform to a corresponding spiral portion ofthe contact carrier, the contact being provided. with an inturned projection 72 (Fig. 6) which serves to position the contact onthe contact car- It will be observed that in this form of my switch mechanismthe insulating contact carrier comprises a pair of cam wheels having spiral cams, and a circular flange extending above the camsand forming an insulating barrier between the contacts can.

ried by the cam wheels.

The switch operating mechanism is so constructed that each'pull of the pull chain 7 As shown in Fig. 6 the cam Wheels of the contact carr1er 72are each provided w th a spiral cam portion 73 against which the spring contact fingers GS and 68 bear during a. part of the movement of the contact carrier. hen the commutator is rotated from the position shown in Fig. 6 the contact fingers 6S and -3 ride upon the surfaces of the spiral cams 73 and finally snapoif from these spiral portions down into contact with the spirally curved contacts 29 and 30. During the neXt 180'degrees of movement, the spring fingers 68 and '68 ride along the spiral contact-s29 and 30 and-finally snap down on" from the ends of the spiral contacts onto the spiral insulating portions 73.

The operation of the switch has been outlined in connection with the description of the construction.

39 through 180 chain is then released,

When the switch is in on position,

that is when the spring fingers 68 and 68:

are in engagement with the contacts 29 and p '30, the circuit is from the wiring terminal 28 throu h the bracket oortion 62, arm

63, contact portion of the contact 29, spring finger 68, base portion 66, spring linger 68,

contact portion of the contactBG, arm 50,

shaft 45, bearingmember 46, bracket 48 and screw e9 to the center contact 26, thence through whatever translating device is inserted in the receptacle,to the shell contact 25, and throughthe screw 36 to the wiring terminal 27. a l

Assuming that the parts are in positions corresponding to that shown in Fig. 6 (in which theswitch is in oii position), the

spring contact fingers 68 and 68 being out of engagement withthe contacts 29 and 30 and resting on the insulating spiral cam portions 73 016 the commutator, i'f/it is desired to move the switch to on position, the chain 421is pulled down until the projection 74 engages the shoulder 7 5 of the insulating base 31. This moves the lever a0 thru 180 degrees and also moves the commutator thru 180 degrees thru theinten' mediary ofthe ratchet mechanism 4L During this movement of 180 degrees, the spring contact lingers 68 and 68 ride upon the spiral portion and at the end or" the movement snap down simultaneously upon the contacts29 and 30 respectively. This simultaneously makes a connection at two points, and completes the circuit between the wiring terminal 28 and the center con tact. the torsion spring 44; returns the switch lever t0 and pull chain 42 to their original position, the commutator however remaining stationary during this return movement of the switch lever t0, the ratchet mechanism ll permitting this return movement or movement of the commutator. The spring The pull chain is then released, and

lingers 68 and 68 would resist a ret'urng movement of the commutator as the ends of these spring fingers would engage the shoulders at the end oi'the spiral cam por- 1 tions 73, and would prevent a return movement of the contact-carrier.

V The return movement of the switch lever 40 under the actionof the torsion sprlng it is limited by the engagement of the projection 7-lwith the shoulder 76 (Fig. 4).

If it is desired to move the switch from ment of 180 degrees, the cormnutator re- During this &

maining stationary during the return of the switch lever. During this forward movement of 180 degrees of the commutator, the spring contact lingers 68 and (38 ride upon the spiral contact 29 and respectively, and at the end of the movement these 7 spring fingers 68 and 68 snap oil from the ends of the spiral contacts, thus making a quick simultaneous double break in the circuit from the wiring terminal 28 to the center contact, thus breaking the are at two points and greatly lessening the chances of injury to the contacts and other undesirable effects.

In the form of my invention shown in Figs. 12 to 90 inclusive the shell and center contacts and 26, the wiring erminals 27 and 28, the electrical connecting member 30 the insulating has 31, the casing 32, the cap 33, the fibre lining 3 2, the fibre cover 35, the screw 36, the pull chain 4-2, the bracket 18, and the screw 1-9, which secures this bracket in place and electrically connects it with the center contact, may be the same as in the form previously described, the main features of difference being in the switch mechanism itself.

The switch mechanism shown in this form of my invention comprises a rotatably mounted connnutator, including a contact 77, (which is always in electrical connection with the wiring terminal s8) a contact 78, (which is always in electrical connection with the center contact 26), and a builtup contact-carrier 79, to which the contacts 77 and 78 are secured, and comprises also a built-up oscillatable switch operating member or lever 80, which as it is oscillated imparts a step by step, movement to the commutator, a ratchet mechanism 81 between the switch lever and the commu tater, and a coil torsion spring 82 for returning the oscillatable switch lever after it has been operated by the pull chain 42.

Many of the details of the switch mechanism are shown in perspective in an en ploded view in Fig. 20. The built-up switch lever or operating member com )rises acentral spider like member 83 (Fig. 20) (having an opening 84 through which the supporting shaft 85 extends) three discs 86, 87, and 88, which are slipped over the legs of the spider 83, and a spacer sleeve 89 which separates the discs 87 and 88 and is also slipped over the spider. These discs 86, 87 and 88 are formed of suitable insulating material, such as sheets of fibre, and the sleeve 89 is also formed of insulating material. The spider 83 is also provided with ratchet teeth 90 for engagement with cooperating ratchet teeth 91, stuck up from the arm 92 of the contact 7 8. The spider 83 may be a suitable sheet metal stamping, as may also be contacts 77 and 78. The pull chain a2 is secured to the switch lever 80 by means of a hook member 93, (Fig. 20) having laterally extending lugs 9 1, which engage openings and 96 respectively in the fibre discs 87 and 88.

The legs of the spider are provided with outwardly projecting portions or lugs 97, to hold the insulating discs 86, 8'7 and 88 and the sleeve 89 in position on the spider.

In assembling the switch lever, the legs of the spider are bent inwardly enough to permit the discs 86 and 87, the sleeve 89 and the disc 88 to be slipped over the outwardly extending projection 97. The cars 9st of the hook member 93 are inserted in the openings 95 and 96 respectively before the discs 87 and 88 are moved up snugly against the ends of the sleeve 89. The discs 86, 87 and 88 are prevented from slipping ofi' at one end by their engagement with the ratchet teeth 90 and are prevented from slipping otl' at the other end by their engagement with the outwardly extending projections 97. In order to position the discs 86, 87 and 88 on the spider 83 and prevent relative rotation therebetween, each of these discs is provided with a number of recesses 98 extending from its central opening, these recesses 98 being provided to receive the legs of the spider, when the parts are in assembled position. The chain 12 is secured to the hook member 93 by engaging one of the balls in the hook portions, the shank which connects the balls lying in the space between the two hook members 99. ' ihc discs 86, 87 and 88 and the sleeve 89 fully insulate the pull chain 42 from the spider 83, (the disc 86 serving to cover up the end of the projection 94, which would otherwise be exposed). The switch lever 80 is supported at one end directly by the shaft (which extends through the opening 8& of the spider), and is supported at its other end by a combined bearing and spring securing member 100 (Figs. 13 and 19) this member 100 having a cylindrical portion 101, which fits inside the legs of the spider 83, and extends through the opening in the disc 88, and thus forms a bearing for the spider and disc.

One end of the coil torsion spring 82 is secured to the spider, as indicated at 102 in Fig. 17, and the other end of this coil torsion spring is secured to the member 100 as indicated at 103 in Fig. 13. The member 100 is adjustably mounted in the bracket l8 in a manner similar to that in which the member 4:6 is mounted in the form of my invention previously described, the member 100 being provided with a struck-up portion 104, which can be made to engage in any one of the notches in the bracket 18, the end of the member 100 being provided with a notch 105, to receive a screw-driver or other suitable tool. By inserting a, screw-driver in this notch, and pressing the member 100 in- Cir wardly, until the lug 104 is disengaged from the notch in the bracket 48, the member can be turnedin either direction, 'to

tighten or loosenthespring as may be de- Letters Patent is: I

sired, to give it the proper tension, and the screw-driver can then be withdrawn to permit the lug 104 to engage the, proper notch in the bracket 48.

The built-up contact-carrier comprises two similar ratchet shaped discs 106 of insulating material (see Fig. 20). these discs supports the curved contact 77 and the other supports the curved contact 78. This contact carrier also comprises a sleeve 108 of insulating material, (which is slipped over the shaft 85 and uponwhich the insulating discs are slipped), and a separating disc 109 of insulating material, also'slipped on the sleeve 108, which serves to insulate the contacts 77 and 78 from each other. The contact 77 is provided with an integral arm 110, extending inwardly, and having an opening through which the shaft 85 extends,

this arm 110 serving to assist in holding the contact in place on the contact-carrier, and

also serving to electrically'connect the contact'with the wiring terminal 28. The insulating sleeve 108 extends through the opening in the bracket portion 62 of the wiring terminal 28, and thus insulates the shaft 85 from this bracket portion, thus preventing a short circuit between the contact 78 and the Wiring terminal 28.

'The contacts are positioned on the discs 106 by means of an inturned lug 111 which engages a corresponding notch 112 which prevents the contact from slipping on its support.

The contact 77 is thus always in electrical connection with the wiring terminal 28, through the arm 110 and the bracket portion 62. The contact 78 is alwaysin electrical connection with the center contact, through its arm 92,,shaft 85 or spider 83, member 100, bracket 98 and screw 4L9.

In the off position of the switch, the contacts 77 and 78 are not electrically connected, being insulated from each other. In moving to the on position of the switch, however, the spring fingers68 and 68 snap into engagement with the contacts 77 and 7 8 respectively and establish electrical connection therebetween. When the switch is moved from on to off position the spring fingers 68 and 68 snap oft ofthe rear ends of the contacts 77 and 78 respectively and thus break the electrical connection therebetween simultaneously at two points, as in the form previously described, thus dividing the arc. I l

The movement of the switch lever 80 is limited to 180 degrees by means of a projection 113 on the disk 88 which engages the shoulder or abutment 7 5 to limit the movement in one direction, and engages the One of ioulder 'Tfi'to limitthe movement in the other direction. j p 'Having thus described my invention, what I claim new and desire to secure by 1. A switch comprising a base, a movably mounted contact carrier of insulating mate.-

rial supported bysaid baseftwo contacts of conducting material mounted on said contact carrier, and insulated -from each other base and arranged to be engaged by both oi? said contacts in their movement, and with respect to whichboth of saidcontacts also move out of engagement 111 their movement,

whereby said contacts are alternately con-- nected and disconnected electrically with respect to eachother by means of said bridgingmeans, said bridging means being provided with a pair of contact tongues strad dling said barrier. 2

2. A mounted. commutator, having two spiral insulating portions lying alongside each other, and two spiral conducting portions lying alongside each other, said'spiral conducting portions being insulated from each other in the off position of the switch, and bridging means of conducting material with which both of said conducting portions make contact in their movement, and with respect to which both oflsaid insulatingportions also make contact in their movement, said bridging means being provided with two contact fingers, said fingers beingarranged to snap o-li said conducting portions on to said insulating portions to break the circuit at two points. simultaneously and to snap o'li' said insulatingportions on to said conducting portions to make the circuit at two points simultaneously.

3. The combination of an insulating base, a.-

rotatably mounted insulating member car- -make and breakthe circuit through the same and electrically connect and disconnect said bearings. 1 v p p 7 4:. A switch socket comprising an insulating base, a wlring terminal and receptacle switch comprising a irotatably ried thereby, ratchet means for rotating said contact supported on saidinsulating base, a

rotatably mounted insulatingmember carried thereby, ratchet means for rotating said member. a pair of switch contacts carried by said insulating member, bearings for said.

insulating member having electrical connection with said contacts, one of said bearings being electrically connected to said wiring terminah aml the other of said bearings being electrically connected co said receptacle contact, and a stationary bridging member arranged to connect and disconnect said switch contacls, and thereby make and break he circuit" through the same and elecl'rica ly connect and disconnect said bearings. 10

in witness whereof, I have hereunto subscribed my name.

CHARLES L. HOPKINS;

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