US2128563A - Contact device for clocks driven by electric motors - Google Patents

Description

Aug. 30, 1938. F. SCHNEIDER CONTACT DEVICE FOR CLOCKS DRIVEN BY ELECTRIC MOTORS Filed Dec. 28, 1935 5 Sheets-Sheet 1 l I 1 J Aug. 30, 1938- F. SCHNEIDER 2,128,563

CONTACT DEVICE FOR CLOCKS DRIVEN BY: ELECTRIC MOTORS 5 Sheets-sheaf. 2

Filed Dec. 28, 1955 v Ema CONTACT DEVICE FOR CLOCKS DRIVEN B Y ELECTRIC MOTORS 5 Sheets-Sheet 3 Aug. 30, 1938. F. SCHNEIDER Filed Dec. 28, 1935 fig.

Patented Aug. 30, 1938 UNITED STATES PATENT OFFICE CONTACT DEVICE FOR CLOCKS DRIVEN BY ELECTRIC MOTORS 2 Claims.

This invention relates to contact-devices for clocks driven by electric motors, especially for the operation of the driving as well as of the striking trains of clockworks for main or master-clocks, 5 clocks for advertisement purposes and so forth.

According to this invention, the motor which serves for driving the clockwork is started by means of two contacts that are made simultaneously, one of said contacts being in the nature of a sliding contact comprising a contact-spring co-operating with a rotating contactdrum, the other of said contacts being of the nature of a pressure-contact comprising a contactspring co-operating with a contact-pin, said latter contact being operated by some other part of the clockwork. The latter contact, moreover, is arranged to assist in closing the circuit established by way of the other contact, while as a whole the two contacts form a double acting safety-device for establishing the electric circuit for the operating current. In an arrangement of this kind the contact-resistance will be essentially reduced, this being attained by the fact that the contact-pin connected to the source of current, such as a battery, simultaneously serves as a carrier for a sliding spring supplying operating current to the insulated contact-roller. A further advantage of the present double contact system is that the contact-surface of the rotating contact-roller is permanently kept in bright condition due to the friction of the contact-arm sliding thereon and, in addition, that the slidingspring for the current-supply is likewise kept in bright condition, even with a slight contact-pressure. According to this invention a third contact is provided which maintains contact with the contact-roller, even in case the first-mentioned two contacts are positively interrupted; By using said third contact the result is attained that the contact-surface of the first two contacts becomes free for subsequently closing the operating circuit and that, on the other hand, the contact including the contact-roller is positively guided as far as to a definite position thereof, even in case the current-source, such as the battery, should be eX- hausted to an extent insuflicient to keep the electric motor running in no-load condition. This mode of operation is of especial advantage, both for the striking-trains of clockworks as well as for master-clocks electrically controlling secondary clocks. In connection with striking trains of clockworks the advantage consists therein that the rack-pin is lifted to a sufficient distance above the notch on the last tooth of the rack 5 during being lifted out of the latter, While in case of master-clocks and secondary clocks there will be the advantage of providing a sufiicient amount of motion for the contact-pin from the respective companion contact-member, such as a contactbar.

An essential novel feature of my new contactdevice consists therein that the center of rotation of the swingable contact-system is at a relatively great distance from that place at which said system is released by the driving-train of the clockwork. By reason of this it will be possible to successfully release the locking-mechanism for the striking-train by means of a small weighted lever lifted by the driving-train, the

weight of said lever being only very small, about one gram. With electric clocks, as known, it is of great importance that they actually keep accurate time without attention. This is attained in the present case firstly, in that the driving-train is required to furnish only the very smallest amount of energy for operating the contacts, secondly, in that a constant very small weight is used for this purpose as a releasing organ, and thirdly, by periodically re-winding the drivingspring of the clockwork at even intervals of time. In this mannner the clocks may be operated to keep time with the greatest degree of accuracy and this even in case the source of current, such as a battery, is almost exhausted. Moreover, for

master-clocks which serve for the operation of secondary clocks, a contact-system constructed according to this invention is of especial importance, because this system will permit the minute-release by the driving-train of the clock to be effected in a very simple manner.

In the drawings I have represented my novel contact-device as well as its mode of operation in connection with a plain driving-train as well as with a striking-train of a clockwork.

Figs. 1, 2 and 3 show my novel contact-device in a side-view in several positions, and more particularly Fig. 1 in the initial locked position, both contacts being open, Fig. 2 in released condition, both contacts being closed, and Fig. 3 again in locked condition, only one of the two contacts being closed. Figs. 4a, 4b, 4c, and 4d are, respectively: fragmentary perspective views of the contact roller together with the contact arms associated therein; a side elevation of the contact roller and its driving gear; a transverse sectional view of the contact roller and its driving gear; and an end elevation of the contact roller and its driving gear. Fig. 5 is a side-view of my novel contact-device used in connection with the driving-train of a clockwork, Fig. 6 shows the drivingtrain forming part of Fig. 5 developed out in a plane, Fig. '1 shows the novel contact-device as applied to a striking-train of a clockwork, and Fig. 8 shows the driving-train forming part of Fig. '1 developed out in a plane.

Referring now more particularly to the drawings, on a pivot 23 fast on the main plate I of the clockwork is mounted a hollow shaft 4| rotatable about said pivot and secured against being drawn off by means of a plate and a locking-pin. Said hollow shaft 4| carries a contact-wheel 22 as well as a contact-roller consisting of an insulating bushing 24 fast on said hollow shaft, of a metal tube 25 placed on said bushing and fastened thereto, and of a metal pin 26 projecting from said tube. From the free end of the contact-roller as far as about to the center of its length a part is cut off, said part extending into said insulating bushing 24 so that at this place there will be provided a cut-away portion 4|] in said contact-roller. Underneath the pivot 23, as shown in Figs. 1, 2 and 3, there is mounted a shaft I6 carrying two contact-arms I1 and I8 together with a horizontal actuating arm I4 of relatively great length. The two contact-arms I1 and I8 are displaced with respect to each other by a certain constant angle, as well as in lateral direction, that is in direction of said shaft I6. The arms I1 and I8, moreover, are in such position with respect to the intermediate contact- rollers 25 and 26 that said arm I8 will be directed towards the cut-away portion 40 of the contact-roller 25. At the free inner end of said arm I8 there is fastened a spring I9, the free inwardly directed end of the latter sliding resiliently on said roller. A further contact-spring 20 is mounted on said other arm I1 on the outer side thereof, the free end of said latter spring cooperating with a contactpin 29 on a contact-bolt 28 mounted in an insulating bushing 21 on the plate I of the clockwork, in such manner that the free end of said contact-spring 20 during swinging towards said bolt will firmly abut against the latter. The contact-bolt 28 is furthermore equipped with a spring 30 sliding with its free end on the full periphery of the contact-roller 25, that is not in the cut-away portion of the latter, said spring 30 serving for the supply of current.

The actuating arm I4 associated with the two contact-arms I1 and I8 is actuated by a spring I5 preferably being rigidly connected to the former at a point as near as possible to the axis of rotation, that is to the shaft I6. At the free end of the actuating arm I4 is a transverse pin I3, by means of which said arm I4 may abut against the vertical arm 9 of a bell crank 8, 9 acting as a locking-lever and being pivoted upon a pin, a pivot 1 on the plate I, said bell crank being actuated by a spring I0 permanently drawing the horizontal arm 8 against a fixed pin II on the plate I. Pivotally mounted about another pin 4 on the plate I is, doub1e- armed lever 5, 6 having straight arms, a short inwardly directed arm 5 and a longer forwardly directed arm 6, the latter carrying at its end a small weight I2. The weight I 2 rests on the horizontal arm 8 of the bell crank 8, 9. The contact-Wheel 2 is rotated by the driving-train of the clockwork and provided with a lateral release-pin 3. Said contactwheel is so positioned with respect to the swingable weighted lever 5, B that during rotation of the former the release-pin 3 will be able to rock said weighted lever when abutting against the short arm 5 thereof.

To the terminal binding post 3| mounted on the plate I of the clockwork is connected the lead 32 which leads to one brush 33 of the electric motor 34, said brush sliding on the commutator 35. The companion-brush 36 likewise sliding on said commutator 35 is connected by a lead 31 with the one pole of the battery 38, the other pole of the latter being connected by the lead 39 with the contact-bolt 28 as shown in Figs. 1, 2 and 3.

Figs. 5 and 6 show, besides the arrangement of my new contact-device with a driving-train for hourly control of secondary clocks, the drivingtrain of the clockwork and the wheels for re-winding the driving-spring, said wheels being mounted between both plates of the clockwork.

To the spindle 42 of the minute-wheel 43 is fixed the arbor 44 for the spring-barrel 45 and the contact-wheel 2 with the contact-pin 3 thereon, while the spring-barrel 45 and its wheel 46 is mounted loosely on the shaft 42 and rotatable thereon. The driving-spring 4B is fastened within the spring-barrel 45 with its inner end to the arbor 44 and with its outer end to some point on the periphery of the spring-barrel. The minute-wheel 43 meshes with the pinion 48 of the wheel 49, the latter being in mesh with the pinion 59 of the ratchet-wheel 5| which forms part of the clockwork. The pawl of the escapement pallet 52 engages with the teeth of said ratchet-wheel 5|. The spring-barrel wheel 41 meshes with the gear 53 and the latter with the gear 54. The gear 54 meshes with a pinion 55 rigid with .a worm-wheel 56, the latter being engaged by the driving worm 51 driven from the shaft of an electric motor. Said driving worm 51 is mounted with its axle 63 in a small bearingbracket 58 fast on the rear plate of the clockwork. One end of the axle 63 carries a slotted coupling-disk 59. On the rear plate of the clockwork there is further mounted a small electric motor 34, the shaft of the latter carrying a coupling-disk with a coupling or catch-pin 6|, the free end of the latter resting with some play in a cut-away portion or slot in the coupling disk 59 which is fast on the shaft of said driving worm 51.

In Fig. 5 the contact-device is shown in open, that is in inoperative position, in accordance with Fig. 1. Fig. 2 shows the contact-device after being released and upon simultaneous contacting of the arm I1 with the roller 25 and of the spring 20 with the contact-pin 29, while the slidingspring I9 is out of action. In Fig. 3 the contactdevice is shown in the position in which the sliding-spring I9 rests on the part of the contactroller that merges into the recess or incision 40 thereon, thus still maintaining the circuit for the final running of the electric motor. As soon as the several parts have come into the position shown in Fig. 1, the device is again in condition of rest. In order to interrupt the circuit, the pin 26 on the roller 25 presses the contact-arm I1 back into its initial position, the contact 2|], 29 being open, while the free end of the slidingspring I9 is still sliding on the peripheral surface of the contact-roller 25, thus maintaining the operating current until the electric motor finally stops. The mode of operation of the contact-system used in connection with the drivingtrain of a clockwork as shown in Figs. 5 and 6 is as follows:

the latter, the pin 3 on the wheel 2 will abut from above against the short arm 5 of the weighted lever 5, 6 pressing the arm 5 of the latter downward, the weight l2 ioeing thus gradually lifted. As soon as the arm 5 during continued rotation slides off the pin 3, the weight I2 falls back onto the arm 8 of the locking-lever 8, 9 rocking the latter counter-clockwise, so that the transverse pin I3 on the actuating arm I4 will drop along the vertical arm 9 of said lockinglever 8, 9. Now the spring l5 comes into action, swinging drawing the actuating arm l4 clockwise (Fig. 5) about the pivot I5. The two arms I! and I8 are thus moved until the contact-arm I'I engages the periphery of the contact-roller 25 as shown in Fig. 2. At the same time, the contactspring 20 fast on the arm I! abuts against the contact-pin 29 so that this double make of the contact will establish the circuit I1, 25, 28, 29, 38, 28, 39, 38, 31, 36, 35, 33, 32, 3| and I6 for the electric motor. Thereupon, the electric motor 34 operates the. driving-train, the pinion 2| now driving the wheel 22 in clockwise sense and simultaneously rotating the contact-roller 25, the latter sliding along the arm I! until this arm is slidingly gripped by the pins 26 on said roller and pressed away from the latter, the one contact 29, 20 being first broken as shown in Fig. 3. Upon backward motion of the arm H the actuating arm l4 had been lifted simultaneously to such an extent that the pin I3 thereon slides along the edge of the arm 9 of the locking-lever 8, 9 and finally permits the latter to swing back into its initial position by action of the. spring III, as far as to i abut against the pin I in which position said pin I3 is again stopped by the locking lever B, 9. Simultaneously with the backward motion of the contact-arm H the contact-arm I8 swinging together with the former is moved in the same direction, so that the end of sliding-spring |9 fast on said arm I8 is pressed against said roller 25, maintaining its sliding contact therewith until said spring drops off the periphery of the contactroller 25 into the cut-away portion 40 thereof, thus effecting complete interruption of the operating circuit for the electric motor. Meanwhile the pin 26 on the contact-roller 25 had been moved out of the. range of action of the. contactarm I! so that the contact-surfaces will again I be free for the subsequent closing of the circuit,

this closing of the circuit taking again place after a revolution of the contact-wheel 2.

In. consequence of the co-operation of the aforedescribed three contact-systems which form part of my present invention, a safety of operation of the contact-device. is attained which had heretofore not been possible. It may be mentioned that a special advantage of my new contact-device is that a uniformly definite end position of the driving-train is attained even though the source of energy (battery) is in weak condition. In the present driving-train the operation of switching takes place after one revolution of the contact-wheel 2, that is every hour, so that the driving-spring of the clockwork will be rewound every hour. It is, however, also possible to use shorter intervals of time for the re-winding of the driving-spring without necessarily changing any essential feature of the system as described. In Figs. 5 and 6 there is shown a gear train which is necessary for an hourly re-winding of the driving-spring.

Figs. '7 and 8 represent an arrangement of my new contact-device in connection with an elec-- trically operated striking-train of a clockwork for half-hour and full hour striking as well as the driving-train of the clock and the wheels for winding-up the clockwork. In principle, the contactdevice is the same as hereabove described and is solely modified to comply with the requirements connected with an electrically operated striking-train. Thus, the contact-wheel 2 on the arbor of the minute-wheel is equipped with two release-pins 3 for half-hour and full-hour release of the striking-train, the one of said pins being mounted nearer the center of the arbor than the other, while the driving wheel 2| in mesh with the wheel 22 on the contact-roller 25 forms simultaneously the control-member for the striking-train. Furthermore, the contact-pin 26 on the contact-roller 25 is omitted. The contactarm i8 is provided at its under part with a noseshaped outwardly curved extension 68. The contact-wheel 2 meshes with the change-wheel 61, which on its part is rotatably mounted between the plate I and the bridge 69, the pinion 68 of said wheel 61 meshing with the hour-wheel 16. At the front of said hour-wheel I9, there is mounted co-axially therewith the snail or stepwheel Fast on the plate I is the pivot 12 which serves as a carrier for the rack 13, I4 having toothed sectors 98, 99 and being mounted swingably about said pivot 12. The under arm of the rack I3, I4 extends towards the contact-arm l8 and comes in engagement with the rounded part of the extension 66 on thearm l8 with its likewise rounded head I4. Together with the rack swings the rack-arm 15 fast thereon, said rack-arm carrying at its forward end the pin 91. The actuating arm |4 forming part of the con tact-device is provided in proximity to its pivot I6 with an upwardly directed locking-nose I6. At the front surface of the wheel 2| which simultaneously serves to drive the contact-roller there is mounted the pin 8| and at the rear surface of said wheel 2| the pin 80 for the rack and in addition an arm TI with a stop I8 thereon. The weighted lever 5, 6 is provided in proximity to its swinging axis with a further arm 82 which extends obliquely in forward and upward direction. Finally, the plate I of the clockwork is provided with a pivot 83 on which there is swingably mounted the detent in the form of a bell crank lever 84, 81. Intermediately of the horizontal arm 84 of said detent is provided a pin 85 adapted to engage with the inner toothed sector 99 of the rack, while the free end of said horizontal arm terminates in a curved part 86 open towards above. The arm 81 of the detent is directed obliquely downwardly and provided at its lower end with a pin 88 engaging with the surface of the arm 82 connected to the weighted lever 5, 6.

The minute-wheel 43 is in mesh with the pinion 48 of the wheel 48, while the latter is in mesh with the pin 58 of the escapement 5|. The pawls of the pallet 52 engage with the teeth of said ratchet-wheel 5|. The spring-barrel wheel 41 is in mesh with the running-wheel 53 and the latter with the lifting wheel 54 carrying the lifting-pins 89. Wheel 54 meshes with the pinion 55 connected to the wheel 2| and the wormwheel 56. The wormwheel 56 is rotated by the worm 51 driven by the electric motor 34 about the shaft 19 and pressed in axial direction by means of the spring 96 against the catch-disk 9| fast on the shaft 19. The disk 9| is axially displaceable on the shaft 19 and may be fixed thereon by means of a small screw. In this manner the pressure and therewith the frictional effect between the spring 99 and the disk 9| may be adjusted. The-shaft for the striking hammer 92 is mounted intermediate the two plates of the clockwork, the horizontal lifting arm 93 of said shaft extending with its free end into the path of motion of the lifting pins 89 on the wheel 54, while its downwardly directed arm 94 firmly abuts against a fixed pin 95 on the plate of the clockwork. The arm of the striking hammer is designated with the numeral 96, said arm striking against a bell, gong or the like, whenever it is actuated.

The mode of operation of my contact-device when used in connection with a striking-train as shown in Figs. '7 and 8 is as follows:

During progressive rotation of the minutewheel 43, of the hour-wheel 10 mounted on the same shaft with said minute-wheel, of the snail or hour-disk 1| and of the contact-wheel 2, the one of the two pins 3 on said latter wheel will abut from above against the short arm 5 of the weighted lever 5, 6, pressing the latter downward. By this, the weight I2 is gradually lifted, while the arm 82 connected to the weighted lever 5, 5 will be pressed against the pin 88 on the arm 81 forming part of the detent 84, 86, 81 swingable about the pivot 83, causing the detent to be lifted by means of the lifting pin 85 on the arm 84 out of the toothed segment 99 of the rack which is swingable round the pivot 12 together with the arm 15. The rack by action of its weight now swings counter-clockwise until the arm 15 abuts with the pin 91 thereon against the snail or hour-disk 1! at the respective step of the latter, while the rounded head 14 on the rack-arm 13 will slide along the nose 66 of the contact-arm l8, thus releasing the latter.

As soon as the arm 5 of the weighted lever 5, 6, upon further rotation of the contact-wheel 2, slides off the pin 3, the weight l2 will drop back onto the arm 9 of the bell crank lever 8, 9, pressing said arm 8 downward so that the lever 8, 9 swings about the pivot 1, causing the transverse pin l3 on the actuating arm M to fall off the vertical arm 9. Thereupon the spring I 5 comes into action releasing the arm 11 on the wheel 2| driving the wheel 22 of the contact-roller 25. The wheel 2| which drives said contact-roller 25 by way of the wheel 22 serves simultaneously by action of pins 89 and BI thereon as a control-member for the backward swinging or backward lifting of the detent 84, 86, 81 as well as of the rack 13, 14, 98, 99 and of the arm 15 co-operating with the snail or step-wheel 1|. By action of the downwardly moving actuating arm l4 the two contact-arms I1, l8 are caused to participate in the motion of said actuating arm until said first contact-arm |1 abuts against the peripheral surface of the contact-roller 25, while the contact-spring 28 on said contact-arm will make contact with the contactpin 29. Now there will be attained a double making of the contact establishing an electric circuit I1, 25, 29, 29, 38, 28, 39, 38, 31, 36, 35, 33, 32, 3|, I5 including the electric motor 34 so that the latter will actuate the driving-train of the clock. The wheel 2| driving the wheel 22 will now be rotated in clockwise sense and simultaneously rotate the contact-roller 25. Upon each revolution of the wheel 2| by action of the pin 8| mounted eccentrically on said wheel 2| the rack 13, 14, 98, 99 at a time is lifted a distance corresponding to one tooth of the toothed segment 98. The pin 89 which is displaced in forward direction with respect to the direction of rotation of the wheel 21 relatively to the pin 8| will now lift the pin 85 on the arm 84 above the curved extenson 86 on the arm 84 of the detent, thus releasing the rack during such lifting motion. Owing to the lead of the pin during further rotation of the wheel 2|, the pin on the arm 84 of the detent simultaneously locks both lever-systems when dropping into the next notch of the toothed segment 99, this dropping taking place prior to the pin 8| Sliding off the tooth with which it had been in engagement. During gradual lifting of the rack the rounded head 14 of the arm 13 slides along the nose or curved extension 66 on the contact-arm l8, at the same time carrying back the system of arms I1, I8, |4 into initial position by action of the bell crank 8, 9. In accordance with the operation of the contact-device in connection with the driving-train the electric motor 34 will be switched out of circuit in this condition of the clockwork.

During rotation of the wheel 2| the wheel 54 is rotated by way of the pinion 55 on said wheel 2|, a proper ratio of gearing being chosen to rotate said wheel 54 through a proper angle, the shaft 92 for the striking-hammer being moved by action of a lifting-pin and by way of the arm 93, thus lifting the arm of said hammer and causing the same to drop so that said hammer will strike against a bell or similar device. If now the other pin 3 comes into action upon further rotation of the contact-wheel 2 at the arm 5 of the Weighted lever 5, 6, the rack 13, 14, 98, 99 as well as the arm 15 on the step-wheel 1| will be released so that half-hour striking is attained in known manner. Upon further rotation of the clockwork the wheel 54 carrying the lifting pin for full-hour striking will be rotated further through a proper angle at a time, so that two, three, four or more lifting pins will act in succession on the arm 93 and thereby on the shaft 92 of the striking hammer in accordance with the temporary position of the step-wheel 1|.

The one of the two pins 3 on the contact-wheel 2 which is nearest the center of rotation of said wheel serves for the release of the half-hour striking mechanism and therefore lifts the detent for the rack only a short distance, causing the release pin 85 on the arm 84 of the detent to drop into the next notch of the toothed segment 99 of the rack, while the other pin 3 which is at a somewhat greater distance from the center of rotation of the contact-wheel 2 serves for the release of the hour-striking mechanism, keeping the rack always lifted by means of the pin 85, until the rack comes to rest by engagement of the pin 91 on the arm 15 with the step of the snail 1| at a required time.

I claim:

1. In a contact device for electric motor wound clockworks in which the motor is periodically energized to wind the driving spring, the combination of a rotatable contact making element having a recess on the periphery thereof, a driving connection to rotate said element, a sliding contact spring engageable with said element to make contact therewith, said contact spring engaging said element at the periphery thereof axially spaced from said recess, a fixed contact pin, a pair of contact arms rigid with respect to one another and mounted for pivotal movement toward said element from the opposite sides thereof, a spring contact member secured to one of said arms and engageable with said element along the recessed portion of the periphery thereof, a resilient contact member carried by the other of said contact arms, said latter member being engageable with said fixed contact pin, an actuating arm rigid with said pair of contact arms, a 75 spring for swinging said contact arms and actuating arm in one direction, means carried by said element for moving said pair of contact arms and actuating arm in opposition to the tension of said spring, latching means engageable with said actuating arm for holding the latter against movement by said spring, and periodically operated means to release said latching means.

2. In an electric motor wound clock mechanism provided with a clockwork having an escapement mechanism, a spring to drive said clockwork mechanism, and an electric motor for periodically winding said spring; the combination of contact means for periodically closing a circuit, said contact mechanism comprising, a rotatable contact drum having a notch in the periphery thereof, the notched portion of said drum being of insulating material, a sliding contact member engageable with the periphery of said drum for continuously making contact therewith, a spring contact engageable with the periphery of said drum in the line of' said notch, a pair of arms rigid with respect to each other and mounted for pivotal movement with respect to said drum, one of said arms being on each side of said drum, a fixed contact pin, a resiliently mounted contact element carried by one of said arms and engageable with said fixed contact pin, resilient means to bias said pair of contact arms for pivotal movement in a direction to bring said resilient contact element into engagement with said contact pin, means rotatable with said drum to move said resiliently mounted contact element away from said contact pin, means for latching said contact arms against movement by said spring, and periodically actuated means to trip said latching means.

FERDINAND SCHNEIDER.

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