US2032671A - Code call apparatus - Google Patents

Description

March 3, 1936. B. H. SMITH CODE CALL APPARATUS Filed May 20, 1931 4 Sheets-Sheet l 1 N VEN TOR. Eyilffim/ffi ATTORNEY? March 3, 1936. B. H. SMITH CODE CALL APPARATUS Filed May 20, 1931 4 Sheets-Sheet 2 Ei-E:

3710 INVENTOR.

March 3, 1936. B. H. SMITH CODE CALL APPARATUS Filed May 20, 191 4 Sheets-Sheet 5 INVENTOR. jgyH/ilin/f/z ca m w 9M4 ay fly? ATTORNE .2

March 3, 1936. B H s H 2,032,671

CODE CALL APPARATUS Filed May 20, 1931 4 Sheets-Sheet 4 70/ Row "H I 1 i l f :L INVENTOR.

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Patented Mar. 3, 1936 PATENT OFFICE coon CALL APPARATUS Boyd H. Smith, Shelby, Ohio, assignor to The Autocall Company, Shelby, Ohio, a corporation of Ohio Application May 20, 1931 Serial No. 538,669

2 Claims.

The present invention, relating as nominally indicated to a code call apparatus, pertains more particularly to an improved mechanism for the transmission of code signals from a central sta-. tion to a plurality of distant and distributed stations. The instant improvements herein provided for are contemplated to be more precisely applied to the apparatus embodying the principle of invention which forms the subject matter of my prior U. S. Letters Patent No. 1,823,221 granted Sept. 15, 1931.

The code signal impulses transmitted by my apparatus may be made audible or visible, that is, they may be ultimately communicated by means of ringing bells or flashing lights, etc. The fundamental features of novelty in the present invention reside in what may most conveniently be termed a supplemental call system and a variable limited call device. In larger establishments such as factories, stores and ofiices, where it is desired to summon individuals to a particular place, it is found convenient to provide a system of call signals, each signal having a distinctive code applicable to a certain individual. In order to transmit additional information to such call signals, such as urgency of call, departmental call, etc., my present invention provides for a means for supplementing the regular code signal with a variety of distinctive general calls. It is a further object of my invention to provide means whereby such supplemental calls may be transmitted together with the regular call, or omitted entirely at the will of the central operator.

Furthermore, the regular calls and supplemental calls may be transmitted for an indefinite continuous period, or for a limited number of repetitions at the will of the operator. Such option may be exercised by simple manipulation of the operating and signal-selecting key. It is also possible to transmit the supplemental signals either prior or subsequent to the regular signals. When making the last-named change, in order to maintain a uniform interval between the cessa tion of the supplemental signals and the inception of the regular code, it is necessary to reverse the coding order of the regular signals. This latter step shall be more definitely described later on in the following description.

Another object of my invention is to provide a means to predeterminately vary the number of limited calls which the apparatus will transmit upon an initial energiaation by the operating key. Such factors as frequency of calls, availability of the persons summoned, size of the establishment,

etc., are determinative of the desirability and number of repetitions of the limited calls.

Further advantageous features which commend the novelty of my invention shall become apparent as the description proceeds. To the accomplishment of the foregoing and related ends, said invention, then, consists of the means hereinafter fully described and particularly pointed out in the claims.

The annexed drawings and the following description set forth in detail certain mechanism embodying the invention, such disclosed means constituting, however, but one of various mechanical forms in which the principle of the invention may be used.

In said annexed drawings:

Fig. 1 is a perspective view of the central station apparatus with the cover in position; Fig. 2 is an end elevation of the apparatus of Fig. l with the side wall of the cover removed; Fig. 3 is a perspective view of the signal selecting and operating key; Fig. 4 is a perspective view of the revolving switch arm; Fig. 5 is a plan view of the interior of the apparatus embodying the principle of my invention, the cover being removed; Fig. 6 is a section taken substantially upon the line 66 of Fig. 5;; Fig. I is a sectional view taken substantially upon the line 1-'l of Fig.5; Fig. 8 is a sectional elevation of the suplemental signal switch; Fig. 9 is a section taken substantially on the line 9-9 of Fig. 8; Fig. 10 is a perspective view of the supplemental switch contact disc; Fig. 11 is an elevational view of the supplemental switch rear insulating block; Fig. 12 is a fragmentary sectional view taken substantially on the line l2-l2 of Fig. 2; Fig. 13 is a sectional view of the motor switch and motor switch operating gear; and Fig. 14 is a wiring diagram illustrative of the various electrical circuits embodied in my apparatus.

Referring more particularly to Fig. 1, the exterior construction of my apparatus consists essentially of the base plate I having mounted thereon the metallic cover 2 which has the side portion 3 and front portion 4. Positioned in the lower part of the front of the cover 4 is the operating switchboard 5 having the selective circuit sockets 6, the supplemental call switch 1 and the pilot lamp panel 8. A plurality of fastening screws 9 are positioned around the base of the cover 2 in order to removably secure it to the base plate I.

In Fig. 2 the interior assembly of the mechanism is generally indicated. Immediately behind the switchboard 5 are positioned the selective switch bars indicated generally at 10, the pilot lamp H, and the supporting brackets [2.

The particular construction and mode of operation of the selective switch bars Ill are not intended to be claimed within the scope of the present invention inasmuch as they are covered by my prior U. S. Letters Patent No. 1,823,221 granted Sept. 15, 1931, and the patent to George Thompson,-No. 1,230,946, issued January 26, 1917.

More or less centrally positioned upon the base plate I is the signal transmitting mechanism. The latter mechanism is resiliently mounted upon the volute springs 14 and I in order to minimize vibration and expedite smoothness of operation of the moving parts.

An operating key as shown in Fig. 3 is provided for the purpose of selecting predetermined circuit connections by means of inserting it into the sockets 6. This key 16 consists essentially of the flattened handle. portion I] composed of insulation having positionedtherein the cylindrical extension 18 composed of conducting material. On the outer end of the extension I8 is the flattened portion l9 which is adapted to make and break contact with the motor energizing bars positioned in the switchboard panel 5 upon rotation of the key l6.

Referring back to Figs. 2 and 5, the code signal transmitting mechanism includes a sector plate I3 of insulating material having positioned thereon the laterally extending contact pins 20 to 26 inclusive, which are circumferentially' disposed and spaced from each other at equal arcuate distances. In the same circumferential line are positioned the supplemental call contact pins 21 to 30 which are also spaced from each other at equal arcuate distances, but such arcuate spacings are different from those of the contact pins 20 to 26 inclusive. Centrally mounted of the above enumerated contact pins is the revolving switch arm 3| having the retaining spring 32 secured in the lateral groove 33 of the metallic block 34 by means of the fastening screw 35.

The revolving switch arm 3| has a transverse groove 3'! which is adapted to carry the contacting brush 38.

As illustrated by Fig. 5, the general interior layout of the apparatus consists of the driving motor 46, the terminal block 4|, the dismissal solenoid 42, the insulated exterior cable collar 43,

the metallic gear train journal plates 44 and 45, the dismissal clutch 41, and the motor governor 48.

The driving shaft 50 of the motor 46 (see Fig.

"7) is journaled in the bearing 5| and carries upon its end the pinion gear 52. The latter pinion gear 52 meshes with a large gear 53 which is preferably made of fibre or similar material. The large fibre gear 53 is secured to the shaft 54 which carries upon its opposite end the small pinion gear 55. The latter gear 55 in turn meshes with another large gear 56 mounted upon and secured to the shaft 51. The shaft 5! likewise carries the small gears 58 and 59 which are shown to best advantage in Fig. 5. The small gear 58 serves to rotate the largesector arm gear 60. As shown in Fig. 12, the large gear 66 is secured to the revolving switch arm shaft 6| which is journaled in the bearing 62 at its innermost end and carries the metallic commutator sleeve 90 and the switch arm block 34 at its outermost end.

Referring back to Fig. 7, the second small gear 59 mounted upon the shaft 5'! drives the gear 63 mounted upon the sleeve 64. The sleeve 65 is carried on the journal stud 65 which, in turn, is

secured to the journal plate 45 by means of the fastening nut 66. Adjacent the gear 63 and also secured to the sleeve 64 is the small gear 67 which meshes with the large motor switch gear 68. The latter gear 68 is of the same diameter as the sector arm gear 65 and is concentrically mounted upon the shaft 6!, but not secured thereto. It will thus be seen that by means of the gear train 59, 63 and 67, that the motor switch gear 68 is caused to rotate in an opposite direction and at a lower speed than that of the gear 66. In the particular form of construction contemplated, the gear ratio of the train 59, 63 and 6'! is so designed that the motor switch gear 68 will rotate at a speed which is one-fourth that of the sector arm gear 68. As best shown in Figs. 7 and 13, the motor switch gear 68 has an integrally formed laterally projecting hub 59 and the diametrically oppositely disposed depressions l6 and H in the lateral gear face. The depressions l6 and "ii are adapted to receive the plunger 12 which is positioned in the sleeve 73 carried by the journal plate 45. The plunger 12 is adapted to actuate the motor switch contact arm 74. When the motor switch gear 68 is rotated in such a position that the plunger 72 is clear of the depressions l8 and 'H and riding upon the face of the gear, the motor switch contact arm 14 will be forced against its associated contact arm 75. The contact arm 75 is positioned against the reinforcing arm '16 and mounted in the insulating switch block H.

The laterally extending hub 69 of the motor switch gear 68 has a flattened portion 80. The plane of the fiat portion 86 is parallel to that of the diametric plane of the depressions and H. A contacting element SI of insulating material is adapted to ride upon the face of the motor switch gear hub 69 and to actuate the contact arms 82 and 33 of the auxiliary motor switch 84.

The outer half of the revolving switch arm shaft 65 carries the solid ring 96 which is insulated from the shaft by means of the fibre sleeve 9!. As shown in Fig. 6, the sector arm brush 92 is adapted to contact with the revolving ring 96. Referring to Fig. 12, the motor switch gear .58 is also adapted to mesh with the dismissal clutch gear 95 which is carried upon the shaft 96. The dismissal clutch mechanism is composed of the clutch driving plate 9'! immovably secured to the shaft 96. On the opposite face of the dismissal clutch gear 95 is positioned the friction plate 98, the degree of pressure which the friction plate 58 will exert upon the clutch gear 65 is regulated by means of the clutch arm 59 carrying the cams N30. The latter cams I06 are held in compression against the face of the friction plate 98 by means of the concentrically positioned helical springs Bill and I02. In order to prevent rotation of the dismissal shaft except upon its proper actuation by means of the dismissal solenoid, which shall be later described, there is provided a metallic disc I53 eccentrically mounted upon the pin N16. The disc I 63 carries the laterally extending and concentrically positioned pin I64 which is adapted to register with the recess H in the face of the dismissal clutch driving plate 91. As shown in Fig. 7 in order to automatically move the stop pin E54 out of registry of the recess I05 when the clutch is shifted into a different lateral position by means of the solenoid 42, there is provided thev tension spring I01 secured to the periphery of the metallic disc I 63 by means of the screw I08. The other end of the tension spring I! is secured to the face of the journal plate 44 by means of the screw I09.

The dismissal solenoid 42 which is adapted to shift the lateral position of the dismissal shaft 96 is essentially composed of the windings H0 and the adjustment means III and the solenoid plunger II2, the latter being coned at H3 to mate with the cup in the end of the stationary core H3 in order to prevent chattering when alternating current is employed.

Mounted upon the outer end of the dismissal shaft 96 is the dismissal code wheel II4 secured thereto by means of the washers I I6 and Ill and the fastening nut H8. The dismissal code wheel H4 has the major portion of its periphery composed of the smooth cam track H5. The remainder of its periphery is composed of the series of radially extending teeth I20 and the transverse recess IIS. The dismissal code wheel follower I2I mounted upon the arm I22 which is pivotally secured to the pin I23 is adapted to ride upon the peripheral surface of the code wheel II4. As the dismissal code wheel rotates, it will impart an oscillating action to the arm I22 which, in turn, functions to make and break contacts between the dismissal contact arms I24, I25 and I26. The stop strips I21 and I28 are secured adjacent the dismissal switch contact arms I25 and I26 respectively in order to limit the travel of the contact arms I25 and I26. The latter contact arms are secured in lateral position by means of the terminal block I29. A fulcrum point I29a is positioned centrally of the base of the terminal block I29 so that by means of adjustment of the fastening screws, the relative angular position of the contact arms I25 and IE6 may be regulated in relation to the oscillating arm I22.

When the dismissal code wheel is in inoperative position, the recess H9 is in registry with the follower i2I, so that the arms I24 and I25 will be in contact. When the follower I2I rides out of the notch I I9, the revolving switch arm circuit is broken with the result that the signal code will not be transmitted. When the dismissal code wheel is rotated into such position that the follower I2I rides upon the teeth I20, the arm I24 will be forced into a series of contacts with the upper switch arm I26, transmitting the dismissal code to the signal relay. When the follower I2I again registers with the recess II9, the revolving switch arm circuit is reestablished.

The construction of the supplemental switch is generally illustrated by Figs. 8 to 11 inclusive.

' Said switch is composed of the contact disc I39 rotatably mounted in the front plate I3I. The insulating blocks I32 and I33 are secured in position to the rear of the plate I3I by means of the fastening screws I34. The contact disc I30 has the laterally projecting shaft I35 upon which is mounted the switch handle I36 which is removably secure-d thereto by means of the set screw I3'I. On the inner face of the switch handle I36 there is positioned the filister head screw I33 which is adapted to bear against the stop screws I39 and I40 in the face of the plate I3I. By means of said screws I38, I39 and I40 it is possible to limit the degree of rotation of the switch handle I36 and its associated contact disc E39. As best shown in Fig. 10, the arcuate contacting strip MI is mounted in the contacting face of the disc I30. The contacting strip I4I has the depressions I42 and I43 which are adapted to register with the contact pins I46 to I49 inclusive. Said contact pins are spring loaded against the face of the contacting strip MI by means of the compression springs I45. A plurality of ball bearings I44 are mounted in the inner face of the plate I3! in order to minimize the rotational friction of the disc I35. The contact pin I46 always remains in contact with the arcuate plate I4 As the disc MB is rotated the contact pins I41, I48 and I49 come successively into contact with the plate IM and are thereby electrically connected to the pin I46.

The wiring diagram (as illustrated in Fig. 14) representative of the various electrical circuits embodied in the apparatus will now be described.

Motor circuit The motor circuit is as follows: wire I56, terminal TI, wire II, terminal Tl, wire I52, motor bars MBI and M33, motor bars M132 and M54, wire I53, terminal T8, wire I54, motor 49, wire I55, terminal TIO, wire I55, terminal T3, wire I51, terminal T2, wire I58. it will thus be seen that the closing of the motor circuit and initial energization thereof is caused by making contacts between the motor bars MBI and MB2 or the motor bars MB3 and MB4.

Motor switch circuit The circuit connections for the regular limited call device which is dependent upon the actuation of the motor switch 'I'I by means of the motor switch gear 68 is as follows: wire I59, terminal TI, wire I5I, terminal T'l, wire I59, wire I65, contact arm I4, contact arm 75, wire I63, wire I6I, terminal T3, wire I54, motor 43, wire I55, terminal TIO, wire I56, terminal T3, wire I57, terminal T2, wire I58. It will thus be seen that actuation of the contact arms 14 and I5 serve to furnish energization of the motor 40 as long as said contacts 14 and I5 remain together.

Variable limited call circuit The circuit connections of the variable limited call device as embodied in the functioning of the auxiliary motor switch 84 is as follows: wire 59, terminal TI, wire I5I, terminal T'i', wire 04, contact arm 83, contact arm 82, wire I62, wire I6I, terminal T8, wire I54, motor 45, wire I55, terminal Th3, wire I55, terminal T3, wire I51, terminal T2, wire I58. When it is desirous to render the auxiliary motor switch inoperative, its power-connecting wire I64 may be connected to the dead terminal T9 as shown by the position of the wire 563. However, when the auxiliary switch 34 is rendered operative by means of the connection of the wire I64, it will be seen that the main motor switch TI is shunted and energization of the motor is continued until both switches TI and 84 open.

Signal relay circuit Wire I50, terminal Ti, wire I5I, terminal T'I, wire I52, motor bars MBl and M133, selective switchboard bars, wires 85 to Hit inclusive, contact pins 20 to 26 inclusive, revolving switch arm 3|, switch arm brush 92, terminal block I29, wire I6'I, contact arm I25, contact arm 24, wire I68,

impulses will be transmitted to the signal relay. The precise construction of the selective switchboard ID has not been illustrated or described in the present specification inasmuch as it forms the subject matter of the United States patent to George Thompson, No. 1,230,946, issued June 26, 1917, and various improvements of which are set forth in my prior U. S. Letters Patent No. 1,823,221 granted Sept. 15, 1931. For the purposes of present convenience, however, in Fig. 14 there is represented the manner in which a regular code signal of single impulse is selected and transmitted. The vertical arrow drawn through the diagrammatic representation of the selective switchboard bars represents the position of the operating key I6. It will be noted that the bars 2I 3I, 4I, 5I, 6-I and 1I have suitably positioned notches in their edges so that the operating key will not contact with them. The sole contact will be made with the switchboard and bar I I in such a manner that the electrical current from the motor bars MB3 and M134 will be supplied only to the bar II, to the wire I85, contact pin 25, and thence to the signal relay as has been already set forth and described.

Dismissal solenoid The energization of the dismissal solenoid 42 and the consequent lateral shifting of the dismissal clutch shaft 96 is accomplished through the closing of the following electrical circuit. Wire I58, terminal TI, wire I1I, terminal T5, wire I12, dismissal switch, wire I13, terminal T8, wire I 14, terminal TI2, wire I15, solenoid 42, wire I16, terminal TIO, wire I58, terminal T9, wire I51, terminal T2, wire I58.

Dismissal code circuit The wiring circuit for transmission of the dismissal code by means of rotation of the dismissal code wheel is as follows: wire I50, terminal TI, wire I5I, terminal T1, wire I59, wire I11, contact arm I28, contact arm I24, wire I68, terminal Ti I, wire I69, terminal T4, wire I10, signal relay, wire I65, terminal T3, wire I51, terminal T2, wire I58. It will thus be seen that the alternate making and breaking of the contacts I24 and I26 will serve to impart the dismissal code impulses over the signal relay cable.

Supplemental switch circuit The electrical connections which render operative the supplemental switch 1 are as follows: wire I 58, terminal TI, wire I5I, terminal T1, wire I18, contact pin I46, contact plate I4I, contact pins I41, I48 or I49, wires I19, I8I, or I82, contact pins 21 to 38 inclusive, revolving switch arm 3I, switch arm brush 92, terminal block I29, wire I81, contact arm I25, contact arm I24, wire I68, terminal TII, wire I59, terminal T4, wire I18, signal relay, wire I65, terminal T3, wire I51, terminal T2, wire I58. Wire I80 connects both the supplemental contact pins 21 and 28 so that the shortest supplemental code signal that it is possible to select and transmit consists of two impulses. It is obvious that a supplemental code signal consisting of merely one impulse would be of no avail since the distinctive feature of the supplemental call signal is dependent upon the differential impulse interval. It will thus be seen that by selection of various contacts of the contact pins I41 to I49 inclusive that a variety of supplemental calls ranging from signals having two to four impulses in the particular instance, may be selected. When switch 1 is turned to the position designated by the letter N (signifying normal), no supplemental code is set up and only the regular code will be transmitted.

Pilot lamp circuit The wiring circuit for the pilot lamp II which is designed to inform the operator of the various calls which are being transmitted is as follows: wire I58, terminal TI, wire I5I, terminal T1, wire I52, motor bars MB! and M33, selective switchboard bars, wires I85 to ISM inclusive, contact pins 20 to 26 inclusive, revolving switch arm 3i, switch arm brush 92, terminal block I29, wire I61, contact arm I25, contact arm I24, wire I68, terminal TI I, wire I84, pilot lamp II, wire I 83, terminal TIE, wire I 58, terminal T3, wire I51, terminal T2, wire I58.

Connected in parallel with the regular call contacts as above described, is the supplemental call circuit which also serves to energize the pilot lamp circuit.

Watchmans circuit The circuit connections for the watchmans circuit which is an optional feature of the apparatus, is as follows: wire I 59, wire 2III, watchmans switch, wire 292, wire I18, signal relay, wire I85, terminal T3, wire I51, terminal T2, wire I58. The result of the closing of the latter circuit will be to transmit an impulse to the signal relay system so that the bells or lights will be energized throughout the plant. The above described watchmans circuit may be used to call the building attendant by pressing the button at the entrance.

The operation of the apparatus embodying the principle of my invention is substantially as follows. When the operating key I8 is inserted in any one of the plug sockets 6 of the selective switchboard I8, and rotated into such a radial position that contact is made between the motor bars, the motor 41! will then become initially energized to cause rotation of the revolving switch arm SI and subsequent contact with the sector pins 25 to 28 inclusive. If the operating key I6 immediately after initial energization of the motor circuit is then rotated back into such a radial position that contact is no longer made between the motor bars due to the flat projection I9 on the end of the key, the operating mechanism will nevertheless continue to be energized due to the fact that the motor switch gear 68 has actuated the plunger 12 to bring together the motor switch contacts 14 and 15. The energization of the gear train and revolving switch arm will continue through two cycles of revolution until the plunger 12 again registers with one of the depressions 18' or II in the face of the motor switch gear 88, at which time the arms 14 and 15 will spring back out of contact and interrupt further operation of the mechanism. On the other hand, if it is desirous to continue the cycle of operations through four repetitions, the wire I84 leading from the auxiliary motorswitch 84 is connected to the power terminal T1 so that the main motor switch 11 will be shunted. In this manner the auxiliary motor switch contact arms 82 and 83 will not be opened until the motor switch gear 68 has completed an entire revolution and its flattened hub portion 88 returns to registry with the insulated follower SI.

When the dismissal signal switch is closed, the solenoid 42 will be actuated. the code wheel II4 put in motion by the switching mechanism (elements 91 to I 8! inclusive), the revolving switch arm circuit opened by the separation of the arms I24 and I25, and the dismissal code signal will then be transmitted, interrupting and superseding the regular and supplemental code signals.

When the supplemental call switch I is so positioned that two or more of the contact pins 21 to 39 are energized, then the supplemental call signal will also be transmitted subsequently to that of the regular code signal. By means of the expedient of changing the relative position of the revolving switch arm 3! on its shaft 6| into the position 3! as shown in Fig. 2, it is possible to transmit the supplemental call prior to the regular code call. As has been previously indicated, in order to maintain a uniform interval between the transmission of the supplemental and the regular codes when the former is transmitted prior to the latter, it is necessary to reverse the coding order of the regular code and of the supplemental code, so that the last impulse of the supplemental code shall occur at the contact pin 30 and the first impulse of the regular code will begin on the contact pin 28. By way of example, supposing that it is desired to transmit a signal consisting of a regular code denoting the number 22 and a supplemental code consisting of three impulses, the contacts 22, 23, 25 and 26 will be connected into the circuit by means of the selective switch plug l6 and the supplemental code contacts 21, 28 and 29 will be connected in the circuit. Thus when the revolving switch arm turns in a counter-clockwise direction, the interval between the last of the regular code, namely, the contact with the terminal 26, and the first impulse of the supplemental code, the contact with terminal 2'5, will be spaced apart at an interval corresponding to the time interval between the terminals 26 and 21. When the transmission of the signal order is reversed, in order to transmit the same code signal, the electrical connections will likewise be reversed so that the terminals 24, 23, 2! and 2% will be connected and the terminals 30, 29 and 28 of the supplemental code will be connected, whereby a uniform interval corresponding to the distance between terminals 20 and 30 will separate the transmission between the two codes. The latter expedient has not been illustrated in the accompanying drawings due to the fact that the reversal of electrical circuits is a device well understood by those skilled in the art.

It should also be observed that the selective switchboard connections are so arranged that I therefore particularly point out and distinctly claim as my invention:

1. In a driving mechanism for a selective signalling apparatus, the combination of a motor for the prime movement of said mechanism, a

motor switch and an auxiliary switch connectible in parallel electric connection therewith, and actuating means for said switches comprising a rotating gear and a hub laterally extending from said gear, the latter having a plurality of concentrically positioned depressions in its face adapted to register with a plunger for actuating said motor switch, and said hub having a flattened portion to register with means for actuating said auxiliary switch, said depressions being adapted to actuate said motor switch at intervals corresponding to the time for the transmission of a certain number of such signals, and said flattened portion being adapted to actuate said auxiliary switch at intervals corresponding to a greater number of repetitions of such signals.

2. In a driving mechanism for a selective signalling apparatus, the combination of a motor for the prime movement of said mechanism, a motor switch and an auxiliary switch connectible in parallel electric connection therewith, and actuating means for said switches comprising a rotating gear and a hub laterally extending from said gear, the latter having a plurality of concentrically positioned depressions in its face adapted to register with a plunger for actuating said motor switch, and said hub having a flattened portion positioned in synchronization with one of said gear face depressions to register with means for actuating said auxiliary switch, said depressions being adapted to actuate said motor switch at intervals corresponding to the time for the transmission of a certain number of such signals, and said flattened portion being adapted to actuate said auxiliary switch at intervals corresponding to a greater number of repetitions of such signals.

BOYD H. SMITH.

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