US1997979A - Automatic clock setting mechanism - Google Patents

Automatic clock setting mechanism Download PDF

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US1997979A
US1997979A US452112A US45211230A US1997979A US 1997979 A US1997979 A US 1997979A US 452112 A US452112 A US 452112A US 45211230 A US45211230 A US 45211230A US 1997979 A US1997979 A US 1997979A
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circuit
controller
switch
disk
motor
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Smith Joseph Brodie
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    • GPHYSICS
    • G04HOROLOGY
    • G04RRADIO-CONTROLLED TIME-PIECES
    • G04R20/00Setting the time according to the time information carried or implied by the radio signal
    • G04R20/20Setting the time according to the time information carried or implied by the radio signal the radio signal being an AM/FM standard signal, e.g. RDS

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  • Patented Apr. 16, 1935 UNITED STATES rare at I SCialrns.
  • This invention relates to setting or correcting mechanism for clocks and it is especially concerned with setting mechanisms designed to utilize the radio time signals which are broadcast by the United States Government daily.
  • FIG. 1 is a diagrammatic View of an apparatus embodying this invention
  • Figs. 4, 5 and 6 are elevations showing successlve operations performed by one of the units of the mechanism shown in Fig. 1.
  • the organization there shown comprises a radio receiving set 2 adapted to receive the radio time signals and to convert said signals into impulses,wor to transmit impulses corresponding to said signals.
  • the time signals start at 11: 55 A. M.
  • the complete set of signals consists of dots sent out at one in at exactly 12 o'clock. As above indicated,
  • the radio receiver 2 is designed to transmit electrical impulses corresponding to the dots of the time signals. These impulses are sent from the receiver through a circuit 3 to a solenoid or electro-magnet I.
  • the armature 5 of this solenoid is pivoted at 6 on a bracket 1, and it is nor-- mally held in a raised position by a coiled spring 8, the movement of the armature under the in- 'fluence of this spring being limited by a' stop screw l0.
  • Carried by, but insulated from, the armature 5 is a-movable contact 12 adapted to engage a stationary but adjustable contact iii to close the setting circuit through one or more cloclrsiii.
  • the radio receiver 2 is inactive, and provision is made for turning it on or bringing it into operation at approximately the time that the signals start, namely, 11:55 A. M.
  • the battery circuit or filament circuit iii of the receiver is arranged to include 2. normally open switch ill which is under the control of a clock mechanism.
  • the clock which may be one of the clocks i l, or an independent clock, as desired, is equipped with a cam disk it so connected with the time mechanism that it makes one complete revolution every twenty-four hours.
  • An arm 2i? pivoted at 28 on the bracket 22 is provided with
  • An arm 2i? pivoted at 28 on the bracket 22 is provided with
  • An arm 2i? pivoted at 28 on the bracket 22 is provided with
  • Antiger 23 which bears against the edge of the cam disk l8 and with another finger 2 3 for engaging one of the spring supported contacts of the switch ill.
  • a spring 25 tends to raise this arm and holds the finger 23 constantly against the cam is.
  • Formed in the edge of this care is a. notch 26 provided with a step 2'21.
  • the edge of this notch slides over the end ofv the finger 23 and permits the spring 25 to move the arm 2Q upwardly far enough to cause the finger M to close the switch ill, as shown in Fig. .4, thus closing the battery in the notch 21 and it remains in this notch for a, brief interval, say two minutes, by the end of which time the disk it has moved far enough to permit the finger 23 to move upwardlystill further until it strikes the bottom of the notch 2t. as shown in. Fig. 5.
  • this motor is of the small synchroin Fig. 2, this controller consisting ci a disk 35 secured fast on or integral with a sleeve 85 carrying a small pinion' 36 at the end thereof opposite to the controller disk. l'nterposed between the disk 34 and the gear 32 is a dished or bowed-spring 31, Fig. 2, which tends to press the disk 34 away from the gear, this movement,
  • controller disk 34 tends to revolve with the gear 32 but it can also be rotated independently or the gear.
  • the controller 34 carries two pins 4c and 4! insulated therefrom, and both designed to engage at certain times with a stop lever 42, Fig. 1. Norv mally the controller is held in the position shown in Fig. l by means of asector 43, pivoted at 44, and connected by a link with an arm 46 which forms part of, or carries, an armature tor the solenoid 41. This arm is pivoted at 48 and it is normally .drawn away from the solenoid by a weak coiled spring 50.
  • this-circuit are simultaneously set to 12 o'clock, this setting action occurring substantially simul- "sector'43 to return the controller disk-34 again a oi the switches 1-1 or 28. Both of these switches normally are held open by the resiliency. of the I and the motor-3i. The presence of the mercury during'all of this time the controller 34 has been held in such a position that the armature 5 could not move far enough to close the switch I 2l3 of the clock setting circuit. The parts are, however, caused to come into a relationship permit- 5 I ting this action at approximately 'two. seconds prior to l2 oclock.
  • each of the clocks i 4 is equipped with some suitable setting mechanism arranged to be operatedby the closing of the circuit so that all'of the clocks in taneously with the final signals. Provision is also made for restoring the controlling apparatus or selector to its initial condi- 12 o'clock dot of the time tion and opening the switches 81 and 28 of the receiving set and motor 3!, respectively, when the setting operation has been completed. For this, P rp se the pin 4!
  • guard is pivoted on the disk 18 at 58 and the spring 59 normally acts on it to hold it yieldingly againsta stop pin 60. It is moved away from this pin by its initial contact with the finger 23 when this finger drops into the notch 26, as shown in Figs. 4 and5, but when it is lowered the guard 51 is swung over the upper end of the finger by the spring. 59, sothat when the switch53 is opened an instant later by thereturn of the controller disk- 34 to its original position and the solenoid i5 consequently is deenergized, the arm 23 then is held in its lowermost position where theflnger 24 cannot close either springs on which the spring contacts are mounted. Both the radio receiver 2 and the motor ll therefore, are turned oil substantially simultaneously with the return of the controller 24 to its initial position.
  • the invention provides a" relatively simple or: 1 on which ll operates entirely automatically to correct or set a clock, or series of clocks, when the time signals are broadcast.
  • the apparatus is relatively inexpensive to manufacture and the various element-s of it are of such a nature that the entire organization has a high degree of reliability.
  • a switch for closing said circuit said switch including a movable contact and another contact with which it cooperates, an electro-magnet operated by each of the impulses of the series, an armature for said magnet carrying said movable contact and tending to cause its engagement with the other contact when the electro-magnet is energized, a rotatable controlling member having provision for preventing the engagement of the movable contact with the other contact in certain positions of the member in response to the energization of the magnet and permitting such engagement in another position thereof, means including a motor connected to said controlling member for rotating it at a predetermined rate in one direction from said certain positions tosaid other position, return means for rotating the controlling member in the opposite direction, a circuit including said return means, and circuit closing means for said last mentioned circuit comprising a second contact carried by said armature and cooperating with said controlling member in said certain positions only, where
  • a switch for closing said circuit said switch including a movable contact and another contact with which it cooperates, an electro-magnet operated by each of the impulses of the series, an armature for said magnet carrying said movable contact and tending to cause its engagement with the other contact when the electro-magnet is energized, a rotatable controlling member having provision for preventing the engagement of the movable contact with the other contact in certain positions of the member in response to the energization of the magnet and permitting such engagement in another position thereof, means including a constant speed motor connected to said controlling member for rotating it at a constant rate in one direction from said certain positions to said other position, return means for rotating the controlling member in the opposite direction, a circuit including said return means, circuit closing means for said last mentioned circuit comprising a second contact carried by said armature and cooperating with said controlling member in said certain positions only, whereby
  • a switch for closing said circuit operative to close a circuit in response to an interval of predetermined minimum length occurring in the reception of a series of electrical impulses
  • operating mechanism for said switch including apparatus arranged to be actuated by the latter impulses, a rotary controller cooperating with said switch to prevent said operating mechanism from closing it in certain positions of the controller but permitting closing movement of the switch in another position of the controller, an electric motor for rotating said controller toward the latter position, electro-magnetic means responsive to the last mentioned electrical impulses to rotate said controller in the opposite direction against the action of said motor, whereby said motor will move said controller into position for the, closing of said switch during an interval of predetermined minimum length in the reception of said signals, electro-magnetic re-setting means for restoring the selector to its initial condition after said switch has been closed, and a circuit for said re-setting means under the control of said controller.

Description

April 16, 1935. J, B. SMITH I 1,997,979
AUTOMATIC .CLOCK SETTING MECHANISM Filed May 13, 1930 2 Sheets-Sheet l RADIO RECEIVER INVENTOR ATTORNEY. I
April 16, 1935. J. B. SMITH 1,997,979
AUTOMA'IiIC CLOCK SETTING MECHANISM Filed May is, 1950 2 Sheets-Sheet 2 INVENTOiEi 2 6g a k ATTORNEY.
Patented Apr. 16, 1935 UNITED STATES rare at I SCialrns. This invention relates to setting or correcting mechanism for clocks and it is especially concerned with setting mechanisms designed to utilize the radio time signals which are broadcast by the United States Government daily.
' read in connection with the accompanying draw- It is the chief object of the invention to devise an apparatus which will automatically reset a clock or series of clocks in accordance with these signals and which will be simple in organization, reliable in operation, and economical to manufacture.
The nature of the invention will be readily understood from the following description when ings, and the novel features will be particularly pointed out in the appended claims.
In the drawings, I
Figure 1 is a diagrammatic View of an apparatus embodying this invention;
Figs. 2 and 3 are sectional and end views, respectively, showing certain details of the con= troller used in the apparatus shown in Fig. 1, together with means for operating the controller; and
Figs. 4, 5 and 6 are elevations showing successlve operations performed by one of the units of the mechanism shown in Fig. 1.
Referring first to Fig. l, the organization there shown comprises a radio receiving set 2 adapted to receive the radio time signals and to convert said signals into impulses,wor to transmit impulses corresponding to said signals. The time signals start at 11: 55 A. M. The complete set of signals consists of dots sent out at one in at exactly 12 o'clock. As above indicated,
the radio receiver 2 is designed to transmit electrical impulses corresponding to the dots of the time signals. These impulses are sent from the receiver through a circuit 3 to a solenoid or electro-magnet I. The armature 5 of this solenoid is pivoted at 6 on a bracket 1, and it is nor-- mally held in a raised position by a coiled spring 8, the movement of the armature under the in- 'fluence of this spring being limited by a' stop screw l0. Carried by, but insulated from, the armature 5 is a-movable contact 12 adapted to engage a stationary but adjustable contact iii to close the setting circuit through one or more cloclrsiii. in the arrangement shown these clocks are all connected in parallel in a circuit supplied with current fromthe battery $16. ,An impu se transmitted through the circuit a 3 and solenoid G will tend to operate the armature 5 to close the switch 'i2-flii of the clock setting circuit 65. This movement, however, normally is prevented by a controlling apparahis or selector so organized that the switch l2 i3 is allowed to close only upon the final dot of the time signals.
Normally the radio receiver 2 is inactive, and provision is made for turning it on or bringing it into operation at approximately the time that the signals start, namely, 11:55 A. M. For this purpose the battery circuit or filament circuit iii of the receiver is arranged to include 2. normally open switch ill which is under the control of a clock mechanism. As shown in Fig. l the clock, which may be one of the clocks i l, or an independent clock, as desired, is equipped with a cam disk it so connected with the time mechanism that it makes one complete revolution every twenty-four hours. An arm 2i? pivoted at 28 on the bracket 22 is provided with afinger 23 which bears against the edge of the cam disk l8 and with another finger 2 3 for engaging one of the spring supported contacts of the switch ill. A spring 25 tends to raise this arm and holds the finger 23 constantly against the cam is. Formed in the edge of this care is a. notch 26 provided with a step 2'21. At approximately 11:55 A. M. the edge of this notch slides over the end ofv the finger 23 and permits the spring 25 to move the arm 2Q upwardly far enough to cause the finger M to close the switch ill, as shown in Fig. .4, thus closing the battery in the notch 21 and it remains in this notch for a, brief interval, say two minutes, by the end of which time the disk it has moved far enough to permit the finger 23 to move upwardlystill further until it strikes the bottom of the notch 2t. as shown in. Fig. 5. In this position of the arm 20 the finger 2C is raised far enough to close a second switch -28 ct a circuit 30 leading to a motor 3i, Fig. 1, which forms a part of theoperating mechanism for the controlling apparatus, above referred to, for determining the precise point in the time signals at which the switch l2-|3 will be closed.
' Preferably this motor is of the small synchroin Fig. 2, this controller consisting ci a disk 35 secured fast on or integral with a sleeve 85 carrying a small pinion' 36 at the end thereof opposite to the controller disk. l'nterposed between the disk 34 and the gear 32 is a dished or bowed-spring 31, Fig. 2, which tends to press the disk 34 away from the gear, this movement,
however, being by a collar 33 secured on the spindle 33.. Due to this arrangement the controller disk 34 tends to revolve with the gear 32 but it can also be rotated independently or the gear. A
The controller 34 carries two pins 4c and 4! insulated therefrom, and both designed to engage at certain times with a stop lever 42, Fig. 1. Norv mally the controller is held in the position shown in Fig. l by means of asector 43, pivoted at 44, and connected by a link with an arm 46 which forms part of, or carries, an armature tor the solenoid 41. This arm is pivoted at 48 and it is normally .drawn away from the solenoid by a weak coiled spring 50.
Assuming that the cam disk I! has been moved far enough to turn on the receiver 2 and to start the motor 3|, it will be clear that-the motor will operate through its connections with the controller disk 34 to revolve the controller slowly in a counter-clockwise direction, as indicated by the arrow in Fig. 1. As each signalv dot is transmitted through the receiver 2 and the electro-magnet 4, the armature 5 is drawn downwardly but. is not allowed to close the switch l2-'-l3 because the spring mounted contact 5|, carried by the arms.- ture 5. strikes the edge of the controller disk 34.
when this occurs currentirom the battery 52 is transmitted through the disk and the solenoid 41, as will be evident from the circuit connections shown in Fig. 1 thus energizing the solenoid and causing it to transmit a quick rotative movement to the. disk 34 in a clockwise diwposition shownin Fig. 1. 'Assoon as the impulse picks up the controller disk 34 and rotates it in rection, this movement returning the disk to the dueto the signaldot dies out, the gear- 22 again a counterclockwise direction, this movement beparticular point in the time signals at which the .controlling apparatus was brought into operaing interrupted a second later by the arrival ofanother dot of .thesig'n'al. These operations are repeated for a length or time depending upon the tion. 1
As above stated, there is an interval of ten seconds immediately prior to 12 o'clock noon. in
which no signal ,dots' are sent, and during this ten second interval the motor 3! and its connections with the controller 34 move the controller far enough to bring the notch 52 in the edge of the controller disk into a position immediately,
" under the contact 5|. This-occurs at about the expiration of the eighth second, or, in other" words, two seconds prior. to twelve oclock. It willbe observed, however, that the longest gap in the time signals prior to'this ten second intervalis an interval of five seconds. and that the spw- *ing of the'contact M from the edge of the notch.
52 is 'sufliciently great to prevent the edge of this I notch arriving in alinenient with the contact during this five second interval. In other words,
this-circuit are simultaneously set to 12 o'clock, this setting action occurring substantially simul- "sector'43 to return the controller disk-34 again a oi the switches 1-1 or 28. Both of these switches normally are held open by the resiliency. of the I and the motor-3i. The presence of the mercury during'all of this time the controller 34 has been held in such a position that the armature 5 could not move far enough to close the switch I 2l3 of the clock setting circuit. The parts are, however, caused to come into a relationship permit- 5 I ting this action at approximately 'two. seconds prior to l2 oclock. Consequently, when the final dot of the signals is received at 12 o'clock and the armature 5 of the solenoid 4 is drawn downwardly, the contact 5! then enters thenotch 52 and the agmature is moved far enough to close the switch l2-I3 of the setting circuit. Each of the clocks i 4 is equipped with some suitable setting mechanism arranged to be operatedby the closing of the circuit so that all'of the clocks in taneously with the final signals. Provision is also made for restoring the controlling apparatus or selector to its initial condi- 12 o'clock dot of the time tion and opening the switches 81 and 28 of the receiving set and motor 3!, respectively, when the setting operation has been completed. For this, P rp se the pin 4! is so located on the controller disk 34 that it strikes the lever 42 immediatelyafter the switch I 2-43 has been closed. This results in closing the switch 53; Fig.4, which controls a circuit including .electro-magnets or solenoids 54 and 55, thus energizing both of these solenoids. The energizing of the solenoid it closes amercury switch 56 which also closes'the circuit through the solenoid 41, thus operating through the armature 46 of this solenoid and the to the position shown in When the solenoid as is energized it draws down the armature 20 to approximately the position shown in Fig. 6, where the end of the finger 23 is htly below the lower edge 01 a guard 51 carri by the cam disk l8. guard is pivoted on the disk 18 at 58 and the spring 59 normally acts on it to hold it yieldingly againsta stop pin 60. It is moved away from this pin by its initial contact with the finger 23 when this finger drops into the notch 26, as shown in Figs. 4 and5, but when it is lowered the guard 51 is swung over the upper end of the finger by the spring. 59, sothat when the switch53 is opened an instant later by thereturn of the controller disk- 34 to its original position and the solenoid i5 consequently is deenergized, the arm 23 then is held in its lowermost position where theflnger 24 cannot close either springs on which the spring contacts are mounted. Both the radio receiver 2 and the motor ll therefore, are turned oil substantially simultaneously with the return of the controller 24 to its initial position.
It will be clear, therefore, that when-the solenoids 54 and 55 are energized the solenoid 55 will disconnector turn oflf both the radio receiver 2 switch 58. serves to delay for a'small interval of time the. energizing ofthe solenoid 4'! which operates to return the controller 34 to its initial position. Consequently; such return of the controller does not occur until after the radio receiver 2 and the motor 3| are turned ofl, the return of the controller serving to deenergize all three solenoids 54,55 and 41.
It will now be anpleciatedthat the invention provides a" relatively simple or: 1 on which ll operates entirely automatically to correct or set a clock, or series of clocks, when the time signals are broadcast. The apparatus is relatively inexpensive to manufacture and the various element-s of it are of such a nature that the entire organization has a high degree of reliability.
While I have herein shown and described a preferred embodiment of my invention, it will be understood that the invention may be embodied in other forms without departing from the spirit or scope thereof. For example, the apparatus shown has been designed to utilize the particular set or series of time signals above described, but it is clear that it would operate equally as well with some other time signals and that an apparatus of essentially the same organization could be used with a considerable variety of time signals to produce essentially the same results.
Having thus described my invention, what I desire to claim as new is:
1. In a selector operative to close a circuit in response to an interval of predetermined minimum length occurring in the reception of a series of electrical impulses, the combination of a switch for closing said circuit, said switch including a movable contact and another contact with which it cooperates, an electro-magnet operated by each of the impulses of the series, an armature for said magnet carrying said movable contact and tending to cause its engagement with the other contact when the electro-magnet is energized, a rotatable controlling member having provision for preventing the engagement of the movable contact with the other contact in certain positions of the member in response to the energization of the magnet and permitting such engagement in another position thereof, means including a motor connected to said controlling member for rotating it at a predetermined rate in one direction from said certain positions tosaid other position, return means for rotating the controlling member in the opposite direction, a circuit including said return means, and circuit closing means for said last mentioned circuit comprising a second contact carried by said armature and cooperating with said controlling member in said certain positions only, whereby during the reception of impulses the return means will be repeatedly operated to rotate the controller in the direction opposite to its rotation by the motor but during the predetermined interval will permit the motor to move the controlling member to a position permitting the first mentioned switch to close its circuit in response to the impulse following the interval.
2. In a selector operative to close a circuit in response to an interval of predetermined minimum length occurring in the reception of a series of electrical impulses, the combination of a switch for closing said circuit, said switch including a movable contact and another contact with which it cooperates, an electro-magnet operated by each of the impulses of the series, an armature for said magnet carrying said movable contact and tending to cause its engagement with the other contact when the electro-magnet is energized, a rotatable controlling member having provision for preventing the engagement of the movable contact with the other contact in certain positions of the member in response to the energization of the magnet and permitting such engagement in another position thereof, means including a constant speed motor connected to said controlling member for rotating it at a constant rate in one direction from said certain positions to said other position, return means for rotating the controlling member in the opposite direction, a circuit including said return means, circuit closing means for said last mentioned circuit comprising a second contact carried by said armature and cooperating with said controlling member in said certain positions only, whereby during the reception of impulses the return means will be repeatedly operated to rotate the controller in the direction opposite to its rotation by the motor but during the predetermined interval will permit the motor to move the controlling member to a position permitting the first mentioned switch to close its circuit in response to the impulse following the interval, further circuit closing means, means operated by the controlling member for closing said further circuit closing means immediately after the closing of the first mentioned switch, and an additional circuit for said return means closed by said further circuit closing means.
3. In a selector operative to close a circuit in response to an interval of predetermined minimum length occurring in the reception of a series of electrical impulses, the combination of a switch for closing said circuit, a radio receiver for receiving signals and relaying electrical impulses corresponding to them, operating mechanism for said switch including apparatus arranged to be actuated by the latter impulses, a rotary controller cooperating with said switch to prevent said operating mechanism from closing it in certain positions of the controller but permitting closing movement of the switch in another position of the controller, an electric motor for rotating said controller toward the latter position, electro-magnetic means responsive to the last mentioned electrical impulses to rotate said controller in the opposite direction against the action of said motor, whereby said motor will move said controller into position for the, closing of said switch during an interval of predetermined minimum length in the reception of said signals, electro-magnetic re-setting means for restoring the selector to its initial condition after said switch has been closed, and a circuit for said re-setting means under the control of said controller.
JOSEPH BRODIE SMITH.
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2614383A (en) * 1945-09-27 1952-10-21 Pfeffer Vaclav Method and device for wireless control of master clocks
US2958179A (en) * 1950-01-23 1960-11-01 Northrop Corp Electronic clock and intervalometer
US4501502A (en) * 1983-07-21 1985-02-26 James Van Orsdel Apparatus and method for timekeeping and time correction for analog timepiece

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2614383A (en) * 1945-09-27 1952-10-21 Pfeffer Vaclav Method and device for wireless control of master clocks
US2958179A (en) * 1950-01-23 1960-11-01 Northrop Corp Electronic clock and intervalometer
US4501502A (en) * 1983-07-21 1985-02-26 James Van Orsdel Apparatus and method for timekeeping and time correction for analog timepiece

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