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Publication numberUS3202779 A
Publication typeGrant
Publication dateAug 24, 1965
Filing dateJun 15, 1962
Priority dateJun 15, 1962
Publication numberUS 3202779 A, US 3202779A, US-A-3202779, US3202779 A, US3202779A
InventorsCall Daniel D
Original AssigneeBell & Howell Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Sensing switch
US 3202779 A
Abstract  available in
Images(3)
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Claims  available in
Description  (OCR text may contain errors)

Aug. 24, 1965 D. D. CALL 3,202,779

SENSING SWITCH Filed June 15, 1962 3 Sheets-Sheet l i col/Nrn I vzgnorx OBJ `Daniel ,D Ca ZZ Aug. 24, 1965 D. D. CAL.. 3,202,779

SENSING SWITCH Filed June l5, 1962 Fri 5.6.

3 Sheets-Sheet 2 if? 46; 12 12 l/ Aug. 24, 1965 D. D. CALL 3,202,779

SENS ING SWITCH Filed June 15, 1962 5 Sheets-Sheet 5 79 azz''i. @all 5 81 FB fp United States Patent C)` 3,292,779 SENSING SWITCH Daniel D. Call, 'Elk Grove, Ill., assigner to Bell & Howell Company, Chicago, Ill., a corporation of Illinois Filed June 1'5, 1962, Ser. No. 202,741 14 Claims. (Cl. 200--61.42)

y endorsing apparatus for which it was particularly devised,

a demand has arisen for a more compact, miniaturized, more simple, faster operating, more directly responsive, more wear free and foolproof version of such mechanism employing the flipper nger or arm principle.

In addition to uses such as in check endorsing apparatus, switches of this sort are well adapted for other 1 electrical control functions where responsiveness to serially moving members is required, and more especially sheet-form members, inclusive of checks, cards, record sheets of various sorts, and the like, which must be accurately individually sensed as they follow a predetermined path. This sensing may be for purposes including actuating `a functioning unit such as -a check endorser, energizing a counting mechanism, and the like. Additionally, because ofsubstantial advances in mechanical and electrical technology that have been made, greatly increasing the speeds of response of electrical systems and gadgetry, and speeds at which sheet processing machines can operate, more direct and higher speed responsiveness in switch mechanism is desirable than has been possible with systems'employing linkages and tripping mechanisms as heretofore.` f

It is, accordingly, an important object of the present invention to provide a new and improved sen-sing switch construction which will meet all of the foregoing and other desirable requirements in vhighly efficient, inexpensive form; f Y

Another object of the invention is to provide a novel sensing switch which, in addition to all oflits other'attributes, is adapted to be constructed in such small and compact size as to be readily mountedin extremely limited lspace,` whereby to afford distinct advantages in manufacturing design of associated apparatus, in keeping with the modern trend toward compactness and miniaturization of equipment.v i

' A further object of the invention is to provide a new A andimproved sensing switch construction which although it is rugged and long lived in service can be embodied in an unusually small and lightweight Yunit.

Still another object of `the inventionis to provide a novel flipper sensing switch construction especially adaptedv for substantially capsular untized form.

Yet another object of the invention is to provide a novel sensing switch construction employing rotary liipper arm motivated means alfordingpo'sitive, high speed step-bystep control. v

It is further an object of the invention to provide novel ysensing switch apparatus wherein a flipper arm Vrotated switch actuating' memberand electrical signal means coact with the dual functions of not only transmitting electrical signals responsive to the rotary movements of the r`oi tatable member, -but also oflmaintaining the rotary member and thereby the associated iiipper linger or arm means normally ina predetermined angular sensing disposition.

`A yet further object of the invention isto provide a new and improved sensing switch construction which lends itself readily to various uses and speed requirements and which functions sensitively in a novel direct-,manner and with great precision.

Other objects, features and advantages of the present invention will be readily apparent from the following detailed description of certain preferred embodiments taken in conjunction with the accompanying drawings, in which:

FIGURE 1 is a sectional elevational view of a sensing switch according to the present invention showing the same installed for use adjacent the path of serially movable sheet members to be individually sensed and with the relationship at the moment of engagement of one of the flipper arms by an advancing member;

FIGURE 2 is a View similar to FIGURE 1 but showing the relationship of parts after the switch has been actuated by movement of the engaged ipper arm by the advancing member;

Y kFIGURE 3 is another view similar to FIGURES 1 and 2 but showing a third relationship of the parts just before full cycle return ofthe switch to starting position;

FIGURE 4 is a sectional elevational detail view taken substantially on the line IV-IV of FIGURE l;

FIGURE 5 is a sectional elevational detail view taken substantially on the line V-V of FIGURE 1;

FIGURE 6 is a sectional elevational detail View disclosing the same switch unit in a slightly modified operating environment; s

FIGURE 7 is a sectional elevational view of a modified switch construction showing it in an operating environment;

FIGURE 8 is an enlarged sectional elevational detail view taken substantially on the line VIII-VIII of FIG- URE 7;`

"FIGUREQ is a sectional elevational detail view taken substantially on the line IXIX of FIGURE S; and

FIGURE 10 is a schematic illustration of utility of the switch in controlling a counter. s.

In anexemplary form of the invention as shown in FIGURES 1-5, a sensing switch structure 10 is constructed and arranged to be mounted on a suitable por-l tion 11 such as a guide trackmember alfording a path ofmovement for successive members `12 such as documents, cards, record sheets, checks, etc., to be sensed. Although for illustrative purposes all of the structures have been shown on ailarge scale, in this instance actu- 'ally in aV four to one ratio of an actual practical size porting means comprising a housing body 13 which is desirably molded from a suitable dielectric material such as a syntheticplastic and providedV with a switch chamber cavity 14.0pening from one face of the housing body.

About the open end of the switch chamber cavity 14 is provided a shallowrecessed seat 15 receptive of a cover plate 17, desirably made from transparent plastic sheet` material to enable inspection of the interior of the chamber. This cover plate 17 has, for convenience in illustration been omitted in FIGURES 1-3, but is shown in FIGURES 4 and 5 and may be permanently secured in place after the switch assembly has been completed.

In order to facilitate attachment of the housing body 13 tothe paper pathway Vguide member 11, as byfmeans of screws 18, a thickened attachment portion 19 is provided along one side of the chamber cavity 14. This enables mounting of the switch unit 10 as close as practicable to the path of movement of the members 12 to be v Highlystablavfree rotaryy support for the l with its distal end portion within the chamber I4 is afforded by 'journalling it in la bearing bore 27 extending through the base wall definingthe .chamber 14 and u., sensed, and in the illustratedexample alongside a longitudinal slot lla'in the member 11 through which sensing means in the form of a flipper arm 2t) of the switch unit is adapted to project across vth'epath of movement the members 12 to be sensed.

Desirably, although only one flipper arm or linger projects into the path of movement ofthe members 12 at anyone time, three of the flipper finger arms are provided on al hub 21. spaced equidistantly, that is, 120 apart. This yhub and the .flipper arms aredesirably made integrally in `one piece from suitable sheet metalsuch Vas stainless steel.' In a desirable form, the hub 2l is of equilateral triangular outline and the flipper arms 2t) extend from the respective sides of the triangle, being bent Irelative to the hub to be disposed in planes 90 relative to one face ofthe hub. This provides an arrangement wherein the flipper armsZ are arranged generally paddle wheel fashion with their broad sides facing in the direction of rotation` about the center of the hub 21 and extending tangent to a circleV described concentric with the center of the hub within the connes of the proximal end portions of the arms.

For rotatably mounting the'tlipperwheel on the supporting housing body13, a shaft 22 made from suitable metal such as stainlessfsteel is provided having adjacent to one end a stabilizing hub and spacer flange 23 of a diameter to be received freely but closely Within the conl insulating sheath 42 of respectivelead wires 43 extending through lead inlet passages afforded by the tubular sleeve rivets and attached at their ends as by means of solder ifi to the respective leaf spring arms.

. In order to provide for the dual functions of switch operating and detenting action, the member 3f? is desirably in the form of a cam having its periphery coactively opposing the signal effecting means and more particularly the spring switch arm 32. Accordingly, fthe member 3i) has its cam periphery provided withr a plurality of successive switch arm biasing projections 45 and intervening detent faces 47.V In the directly corotatively. coupled relationship of the shaft 22 and the cam member 30, the peripheral outline of the cam member is preferably of equilateral triangular form with the projections 45 at the apices of the triangle and the detent faces providing the sides of the triangle. Location of the shaft 22 is adjacent to but spaced from the back 3l aslshownV in FIGURE l. This holds the shaft 22 and rfines of the proximal end portions of the flipper arms Ztl 1 (FIGS. l, 4 and 5). Attachment of the shaft hub 23 to the flipper hub 2l is convenientlyV effected by means of a riveted or` peened over central projection 24 on the hub 23 received through a complementaryy central aperture-Z in the flipper hub 21. r`

shaft 22 aligned external and internalrespective spacer bosses 2S and29 on such wall. .The length of. the'spacerboss 2S is sufhcient to maintain an` adequatespacing of'theadljacentmedges of the flipper arms 20 from the housing. 13V with the opposing face ofthe attachment and spacer hub flange 23 freelyengageably opposingkthe outer end of the externalv spacer boss;

' Meansare provided whereby in the rotationof the u ishaft 22,' as motivated by the flipper arms `2f) throughy ythe corotative hub attachment described to operateelecthereby the flipper arm wheel stationary until rotary or torque' pressure is applied toV one of the flipper arms Ztl to effect rotation.

` Disposition of thecam member 30 with respect to the flipper arms 26 is such that'in the detenting coaction of the spring arm 32 and a face k47 of the cam member one ofthe respective flipper arnrsZf) is located across the path of movement of the sheet members 12 to be sensed in travelling past the sensing switch 10, so that the leading edge of the member `12 will engage and swing the flipper arm in the direction offadvance of the member l2. Such interengagement is enhanced, and adequate swinging movement of the flipper arm 2t) is afforded to actuate the sensing switch, by a' normal inclination of this trigger-poised .arm toward the advancing edge of the member 12. In addition, eachof the arms 20 preferably has a terminalend kportion-48 angled to provide a bias toward the `advancing edge of the document member "12 and serving asaV lead-in andy engagement finger for the document edge.

combination switch operatingl and detenting member 3f) i leaf spring switch arms 3l and 32. carrying respective.

opposed electrical contacts 33 and 34; Mounting of the switch arms 3l and- 32 is such that one of them, herein the arm 32 is disposed to Vbe operatively engaged by the cam member 3.6).'

Y y In the exemplary sensing switch V10 shown, the switch. armsf31 and 32 are mounted in spaced superposed relation to maintainthe contacts 33 and 34 in normally separated .lopen switch relation.` VTo this end, the housing body V13 is provided within the chamber 14 on the side thereof oppositel tothe attachment portion 19 with a pair of steppedlands or platforms35 and 37 to which the switch'arms Bland 32 are respectivelyiattached cantilever fashion. Attachment is effected by means comprising identical, i respective tubular rivets 33 extending through respective bores39 through the adjacent wall of the housing body 13 which iat the outer side is counterbored as at fil) andfflll to accommodate rivets 'of as short as practicable length and also to receive end portions of As thesheet member 12 drives against the engaged flipper armti and swings it in the direction of movement of the `sheet member, the flipper wheel is turned to rotate. the. cam member 3f) countercloclwvise as viewed in FIG- URES l and`2 and thereby driving the contiguousfcam projection 4S toward and against the spring contact arm 32, as best visualized inFIGURE 2. ySince the switch .arm 32 is ofv substantial length and thus, resiliently flexible it affords only moderate resistance to flexure affording, in 'a practicalunit,yieldability in response to about seven grams force thrust against the triggering flipper arm 2li. `In order' to reduce frictional'resistance' to a tions 45 are curved on a -suitable radius.

During its arcfoffrnovement, the switch,v arm pressing cani projection' 45; sufficiently depresses. the 4switch arm ,32, to effectrm engagement Vof the contacts 33 and 34, with the opposing switch arm 3l affording cushioning resilient flexure yieldability, as indicated in FIGURE `2, and pressure -reliefafter the contacts have been closed.

Thereby, en electrical circuit through the leads 43 is leadsf may be included comprises a suitable power supply. 49 and; a counter 5f) of any preferred'electrically energized typeL commonly employed on machines where a record of the number of operationsornumber of units handledby a' machine is desired. Thus, upon closing ofl thel switch-10- through driving of the switch contacts, into 'closing relation by theV cam member 3l) Van electrical; Qrwit Vialnule'is supplied t0 the CounterV Si?. t0

effect recording of the fact that the switch has been actuated by movement thereby of one of the sheet members 12. This is repeated for each of the sheet members and thus affords `a count of the number of sheet members handled by the associated machine in any period of operation.

After the flipper arm 2t) in triggering position has been swung about 80 from its initial position in FIG- URE 1 to the position shown in FIGURE 2; wherein it clears the motivating sheet member 12, the switch arm engaging cam projection 4S moves sufficiently beyond center for the spring load reaction developed in the flexed spring arm 32 to snap the cam member 3i) and thereby the flipper arm wheel at an accelerated rate in the rotationally advancing direction so that the succeeding flipper arm 20 swings toward the opposing face of the motivating sheet member 12 until the finger terminal 48 thereof engages the trailing marginal portion of the sheet member as shown in FIGURE 3 to assure instantaneous movement of the terminal end portion of such flipper arm into the gap between the trailing edge of the motivating member 12 and the next succeeding sheet member 12, even though such gap may be quite narrow. Such ipping of the end of the arm 20 against such trailing edge of the motivating sheet member may even be accompanied by a slight deflection of such trailing margin and thus affording further assurance -that the finger terminal 4S will enter into sensing position with respect to the advancing edge of the next lsucceeding sheet member 12. As this action occurs, the points or contacts 33 and 34 separate as shown in FIGURE 3. As soon as the flipper arm 20 leaves the trailing edge of the .member 12, the next succeeding detent face 47 of the cam member 3@ is snapped by the spring action of the arm 32 into detenting coaction therewith so that overrunning of the ipper wheel is avoided and should there not be a succeeding sheet member 12 or should the gap between such succeeding and the preceding sheet member be unusually wide, the flipper arm 20 that has been moved into triggering position will maintain that position until the leading edge of the succeeding member 12 engages and swings the triggering arm to repeat the sensing cycle.

In the modification'of FIGURE 6, the same sensing yswitch 1t) is employed but in order to adequately handle sheet members 12 which are quite thin, a retainer track guide bar or plate structure 51 is mounted in suitably ,spaced relation to the transporting face of the supporting member 11 to provide a guideway S2 within which the advancing thin sheet member 12 is guided to move in its plane and thus assure adequate coaction of its leading edge with the triggering flipper arm 20 as shown. Gtherwise, it will be understood that operation of the sensing switch 1t) is identical to that already described.

Where it is desired and practical to have the gap between the contact points of the switch arm substantially closer than provided by the arrangement of the switch 10, a sensing switch structure 53 as shown in FlGURES 7-9 may be employed operating on substantially the same principle but embodying mechanism which reduces the switch arm throw or fleXure to effect closing of the contact points. Accordingly, the switch 53 ha-s a flipper wheel structure which is substantially the same as that employed in the sensing switch and includes a plurality, herein three circumferentially equally spaced iiipper arms S4 projecting from a triangular hub 55 and each provided with an angular lead-in terminal finger flange 57.

Centrally the hub 55 is secured to the end portion of a shaft 5S by riveting over the end lof the shaft to clamp -the wheel hub against a spacer flange S9 integral on the shaft. This shaft 58 is rotatably journalled through rerepective opposite face wall panels 6ft of a body member including an integral connecting web portion 61 arranged to provide an attachment base adapted to be secured by means such as screws 62 to a supporting member 63 affording a guide path for sheet members 64 to be sensed by the arms S4 successively projecting through a clearance slot 65 in the member 63.

Completing the body of the switch member 53 is a generally U-shaped dielectric member 67 fitting snugly between the margins of the wall panels 60 vand secured in place by means such as screws 68 threaded into threaded bores 69 in the base member 61. This provides an enclosed housing chamber 70 within the switch body wherein are mounted respective switch arms 71 and 72 having opposed respective closely spaced switch contact points 73 and 74. The switch arm 71 is the shorter of the arms and is mounted cantilever fashion on a stepped offsetting platform portion 75 on the connecting web portion of the housing member 67 opposite the base portion 61, while the longer resiliently tiexible switch arm 72 is mounted on an offsetting platform step 77. It will be understood that since the housing portion 67 is made from a dielectric material such as a suitable moldable plastic, it may conveniently be transparent.

Attachment of the switch arms 71 and 72 is effected by means of tubular sleeve rivets 78 similarly as described in connection with the switch 1t), accommodating electrical lead wires 79 therethrough electrically connected to the switch arms as by means of solder 80. Respective coun-terbores 81 and 82 outwardly from the platform offsets 75 and 77 accommodate the end portions of insulating sheaths 83 for the electrical lead wires 79.

In the switch 53, the flipper wheel shaft 58 is mounted adjacent to the mounts for the spring arms 71 and 72, and the end portion of the shaft opposite the iiipper wheel projects beyond the housing wall and has corotatively attached therto a small gear or pinion 84 which meshes with a larger gear 8S corotatively attached to an end portion of a cam shaft 87 also rotatably journalled through the wall panels 60 in suitably spaced parallel relation to the shaft 58 `and carrying corotatively fast thereon, within the chamber 70 a switch actuating cam member 8S. In the illustrated embodiment, the gear wheel is made from a dielectric material and the shaft 37 has a spacer collar flange 89 thereon between the gear 85 and the adjacent housing wall 6). A spacer hub 90 on the gear 84 serves the same purpose.

In order to accommodate the small gap for closing of the switch contacts 73 and 74, the cam member S8, which is also preferably made from a dielectric material, is provided with twice the number of switch closing projections 91 and detent faces 92 on its periphery as there are ipper arms 54. Thus, in the arrangement shown, there are six of the prejections 91 and of the detent faces 92 and it will be understood that these projections and faces coact with the longer resiliently flexible switch arm 72 in the same manner as the c-orresponding projections 45 and detent faces 47 of the switch 10. However, because the switch actuating projections 91 project to a shorter distance relative to a circle through the centers of the detent faces than is true with respect to the three-projection cam member 30, the projections 91 depress the switch arm 72 a correspondingly shorter distance, but ample to effect full closing of the contacts 73 and 74 during the sweep of each of the projections 91 cyclically against the switch arm 72.

As each of the flipper arms 54 is swung by the advancing document member 64 it rotates the shaft 58 and thus the gear 84 through one-third of a revolution. By having the gear 85 in a 2-to-1 ratio to the gear 84, the gear 85 will be rotated one-sixth of a revolution and effect corresponding revolvement of the cam 88 to advance the same by one projection and one detent face in each sensing cycle of operation of the switch 53.

It will be understood that modifications and variations may be effected without departing from the scope of the novel concepts of the present invention.

I claim as my invention:

l. In a sensing switch construction,

supporting means adapted to be disposed adjacent to the path of movement of successive members t0 Vbe sensed as they pass thereby and including attachment structure for securing itin operative position relative to said path,

a shaft rotatably supported by said supporting means,

a liipper arm carried by said shaft and of a length to extend beyond said supporting means and to project across' said path of movement of the membersV so as to be engaged thereby to rotate said shaft,

electric signal effecting means carried by said supporting means,

and a member having a periphery opposed to said signal effecting means and rotatably actuated by said shaft to operate said signal-effectingfmeans,

lsaid periphery of said member and said signal-effecting means coacting to maintain said rotatably actuated member and thus saidshaft and said flipper armin a normal disposition wherein said arm projects across said path.

2. A sensing switch construction as delinedin claim 1 wherein said electrical signal effecting means includes a spring arm, and said rotatably actuated member comprises a cam s-tructure having on said periphery a projection which engages and liexes said spring arm when said liipper arm effects rotation of said shaft, said periphery .also having a detent face coacting with said spring arm to maintain said normal disposition.

3. In a sensing switch construction as defined in claim 1, said'rotatably actuated member having a shaft rotatably mounted on said supporting means, and a gear train connecting the arm-carrying shaft and said rotatably actu- Y ated member shaft for coordinated rotary operation when said arm-carrying shaft is rotated by `the `flipper arm.

4. In a sensing switch construction, Y

a supporting body defining an enclosed chamber theremeans for mounting said body adjacent to the Vpath of movement of a succession of members to be sensed `as they pass thereby, Y

a shaft rotatably supported by said body, f'

a flipper wheel carried by said shaft externally of said chamber and-having a plurality of circumferentially spaced flipper arms each of :a length to extend beyond said supporting body and adapted to project successively into the path of movement of the members to be sensed so as tobe engaged bythe members to rotate said shaft,

electrical signal effecting means mounted within-said chamber, l

and means actuated by said shaft in the rotation therey of for operating said'signal effecting means.

5. ln a sensing switchconstruction,

a supporting body defining an enclosed chamber therein,

'means for mounting said body adjacent to the path of movement of a succession of members to be` sensed as they pass thereby,

a shaft rotatably supported by said body,

a flipper wheel carried by said shaft externally of said chamber and having a plurality of circumferentially spaced flipper arms each of a length to extend beyond said supporting body and Yadapted to project successively into the path of movement of the members to'be sensed so as to be engaged Vby the members to rotatesaid shaft,

electrical signal effecting means mounted within said chamber,

said signal effecting means including a spring arm,

and a cam member directly engaging said spring arm and operatively connected with said shaft for rotation when the shaft is rotated by said flipper arm elfecting means.

6. In a sensing switch construction,

a supporting body defining an enclosed chamber therein,

means for mounting said body adjacent to the path of movement of a succession of members to be sensed asthey pass thereby,

a shaft rotatably supported by said body,

a llipper wheel carried by said shaft externally of said chamber and having a plurality of circumferentially spaced flipper arms each of a length to extend beyond said supporting body and adapted to project successively into the path of movement of the members to be sensed so as to be engaged by the members to rotate said shaft, electrical signal effecting means mounted within said chamber,

said signal effecting means including a spring arm,

and a cam member directly engaging said spring arm and operatively connected with said shaft for rotation when the shaft isrotated by said flipper arms for moving said spring arm to operate said signal effecting means,

said cam member having a series of detent faces thereon coactive with said spring arm to maintain the cam and thereby said shaft against overrunning.

7. In asensing switch construction,

a housing delining a switch chamber therein,

a pair of opposed switch contacts mounted on said housing within said chamber and one of which is carried by a spring arm attached at one end to the housing and normally biasing said one contact away from the other contact,

a rotary shaft mounted on said housing within said chamber and having a cam member thereon engaging said spring arm,

said cam member being rotatable with the shaft and having a portion thereon acting during rotation of the cam member to liex said spring arm and thereby move said one contact into closing engagement with the other contact,

a portion of the shaft extending out of the housing,

and means carried by said portion of the shaft and engageable by an object to be sensed to effect rotation of the shaft. p

8. In a sensing switch construction,

a housing defining a switch chamber therein,

a pair of opposed switch contacts mounted on said housing within said chamber and one of which is carried by a spring arm attachedk at one end to the housing and normally biasing said one contact away from the other contact,

a rotary shaft mounted on said housing within said vchamberand having a cam member thereon engaging said spring arm,

said cam member being rotatable withthe shaft and having a portion thereon acting during rotation of the cam member to liex said spring arm and thereby move said one contact into closing engagement with the other contact, n

a portion of the shaft extending out of the housing,

and a sensing arm carried by said portion of the shaft and projecting beyond the housing to be engaged by a member to be sensed for rotating the shaft and thus rotating the cam to actuate'said spring arm and close said contacts.

9. In a sensing switch construction,

a dielectric housing having means thereon for securing it to a support adjacent to the path of movementiof a Vsuccession of 'members to be sensed on the support,

said housing lhaving a switch chamber therein,

a pair of opposed electrical contacts mounted in said switch chamber,

a resiliently flexible spring arm carrying one of said contacts and normally biasing said one contact away from the other contact into switch-open position,

a shaft carried by said housing and extending across said chamber,

a dielectric cam member carried corotatively by said shaft and having a series of peripheral detent faces and intervening arm biasing projections,

said detent faces coacting with said arm to maintain the cam and shaft normally stationary,

and means outside of said chamber and operatively connected with said shaft and arranged to be interposed in said path of movement to be motivated by said members and thereby to rotate the shaft and said cam member and drive said projections to flex said arm to move said one contact into closing relation to the other contact.

10. In a sensing switch as defined in claim 9, said means outside of the chamber for rotating the shaft comprising a plurali-ty of flipper arms mounted on and projecting laterally from the shaft, and said cam having projections and detent faces each corresponding in number to the flipper arms.

11. In a sensing switch construction,

dielectric means defining a housing having a switch chamber therein,

relatively offset platforms in said chamber,

respective resiliently flexible switch arms mounted cantilever fashion on said platforms in spaced relation and having on their distal end portions respective normally spaced contacts which are opposed to one another and normally in spaced relation,

a shaft mounted on said housing in said chamber in spaced relation to one of said arms adjacent to said contacts,

a cam corotative with said shaft and engaging said one arm,

said cam having a detent face coactive with said one arm in the spaced contact disposition of the arms t maintain the cam and shaft in a normal at rest position and having a projection operative in the rotation of the cam to flex said one arm toward the other of said arms to close the contacts,

said shaft having an end portion externally of said housing,

and a flipper arm wheel corotative on said end portion and including a flipper arm adapted to be engaged by a moving member to be sensed and swung thereby to rotate said shaft and thereby rotate said cam to drive said projection against said one arm to flex it and close said contacts.

12. In a sensing switch construction,

a housing defining a switch chamber,

said switch chamber having mounted therein opposed electrical contacts one of which is carried on an end portion of a spring arm attached cantilever fashion on its opposite end portion to the housing in the chamber and normally biased to open contact position,

a rotary shaft carried by said housing in said chamber adjacent to said arm and having a portion outside of the chamber,

a cam on said shaft having its periphery in engagement with said arm,

a flipper arm wheel carried by said portion of the shaft and having three flipper arms disposed 120 apart circumferentially,

said cam having a substantially triangular periphery v with three projections and three intervening detent faces,

said projections being successively operable in the rotation of the cam to press against said arm and deflect it to move said one contact into engagement `with the remaining contact and said detent faces being successively engageable with said arm in its biased position to retain the cam and shaft and wheel in respective dwell positions,

said detent faces and said switch arms being relatively oriented to maintain the arms in said dwell positions in a predetermined relation to the housing for engagement by a relatively moving member to be sensed and to be swung thereby to rotate the shaft and the cam to drive one of said projections against said switch arm and swing it into contact-closing position,

said projections having surface contours cooperable with said switch arm for reacting to the arm bias after 80 rotation of the shaft with the respective projections in engagement with the arm to snap the cam in rotary direction and move the succeeding detent face rapidly into dwell engagement with the switch arm.

13. In a sensing switch construction,

means providing a housing having means attaching it to a support with -respect to which a succession of members to be sensed move,

said housing defining a switch chamber,

means in said chamber supporting a pair of switch contacts and including a spring arm carrying one of the contacts and normally biasing such contact away from the other contact into switch-open position,

a shaft carried by the housing in said chamber and supporting a corotative cam,

said cam having a plurality of detent faces and switch arm actuating projections arranged to engage said spring arm successively in the rotation of the cam,

a second shaft carried by the housing on a rotary axis spaced from the first mentioned shaft and having a portion outside of said chamber,

a gear train connecting said shafts,

and a flipper arm wheel carried by said portion of the second shaft and having arms of a length to project into the path of movement of the members to be sensed,

said cam having twice the number of projections and detent faces as the number of arms.

14. A sensing switch construction including:

supporting means including means for mounting the same adjacent the path of movement of a succession of members to be counted as they pass thereby,

a shaft rotatably supported by said supporting means,

a flipper arm carried by said shaft and of a length adapted to project across the path of movement of the members so as to be engaged thereby to rotate said shaft,

electrical contact means for connection in a counteractuating electrical circuit and supported by said supporting means,

said electrical contact means including a resiliently biased arm normally maintaining said contact means in open circuit relation,

and a cam member rotatably actuated by said shaft and having a periphery opposed to said biased arm and functioning during rotation of the shaft by the flipper arm to operate said biased arm to close said contact means,

said periphery having detent means coactive with said biased arm normally to maintain the cam member and thereby the shaft in an at-rest position and to avoid overrunning of the shaft.

References Cited bythe Examiner UNITED STATES PATENTS 2,126,967 8/38 Lyons 23S- 92 2,278,087 3/42 McLaughlin 235-98 2,802,914 8/57 Karkow 20G-61.41 2,940,667 6/60 Hawkes 23S- 98 2,974,862 3/61 Eichorn 23S- 98 BERNARD A. GILHEANY, Primary Examiner.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2126967 *Nov 9, 1937Aug 16, 1938Lyons Charles ENewspaper counting apparatus
US2278087 *Oct 26, 1939Mar 31, 1942Mclaughlin William HMeans for actuating electrically controlled mechanisms
US2802914 *Sep 28, 1955Aug 13, 1957Bell & Howell CoSwitch operating mechanism
US2940667 *Sep 18, 1957Jun 14, 1960Emory L Groff JrEgg counting device
US2974862 *Aug 14, 1957Mar 14, 1961IbmDifferential counter
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3317131 *Sep 23, 1965May 2, 1967Walsh Richard WCounter-actuator device
US3594519 *Jan 9, 1970Jul 20, 1971Addressograph Mulltigraph CorpSwitch assembly feeler
US3806677 *Jan 15, 1973Apr 23, 1974Stop Motion Devices CorpDetector mechanism for broken strands of yarn
US3867593 *Nov 7, 1973Feb 18, 1975Diebold IncPneumatic tube carrier detector assembly with cam operated microswitch and resilient finger heeler means
US3912890 *Jun 12, 1974Oct 14, 1975Bacom IncSensing switch having resilient finger sensor for detecting a document
US4148393 *May 27, 1977Apr 10, 1979Wiseman Raymond LSensing device and method
US4328402 *Aug 27, 1979May 4, 1982Bell & Howell CompanySensing switch for detecting a document
US4671441 *Apr 24, 1985Jun 9, 1987Mannesmann AgMonitoring plural feeding in printers
US4960966 *Nov 6, 1989Oct 2, 1990Enterprise Sales & Company Inc.Limit switch
Classifications
U.S. Classification200/61.42, 235/98.00R, 200/568
International ClassificationH01H35/00
Cooperative ClassificationH01H35/00
European ClassificationH01H35/00