US2559910A - Electric timer - Google Patents

Description

W. M. WHITE ELECTRIC TIMER July 10, 1951 Filed Sept. 25, 1946 FIG.1.

INVENTOR FIG.4.

'WYLLMM M. M/IiITE Z I I Ii ........FE....... DRE w w m 4 3 L 3 3 9 1 J 1 m Patented July 10, 1951 rric ELECTRIC TIMER William M. White, Rochester, N. Y., assignor to Eastman Kodak Company, Rochester, N. Y., a corporation of New Jersey Application September 25, 1946, Serial No. 699,225

9 Claims.

The present invention relates to timers, and more particularly to exposure timers for use in connection with photographic printers.

The purpose of such a timer is to provide electrical actuation as well as synchronous motor operation for the controls of printer lamps. A preset-table pointer is movable over the timer scale to a position to indicate a desired or predetermined time inteval. A self-starting synchronous clock motor is directly connected to and is adapted to drive a, shaft on which a second or timing pointer is loosely mounted. The timer is started by momentarily closing a switch of a self energizing relay. When the relay is thus energized, it serves to close a switch in a circuit to the motor and printer and simultaneously connect the second pointer to the drive shaft. The presettable pointer carries a switch arranged in the relay circuit and position d to be engaged and opened by the second pointer at the completion of the interval to open the circuit to the relay to disconnect the second pointer from the drive shaft and to open the switch to the motor and printer circuit. Thus the closing of the starting switch turns on the printer lamp and starts the timer. At the completion of the predetermined time, the timer motor is automatically stopped. and the printer lamps are extinguished.

The present invention has, therefore, as its principal object, the provision of a timer which may be adjusted selectively for various time intervals.

Still another object of the invention is the provision of a timer which automatically cuts off the printing lamps at the expiration of a predetermined time.

Yet another object of the invention is the provision of an arrangement for automatically connecting the timing pointer to the timing mechanism when the latter is started and for automatically disconnecting the pointer when the timing interval has elapsed.

A further object of the invention is the provision of an arrangement by which the moving timing pointer is utilized to open the motor and printer circuits at the end of the time interval.

And another object of the invention is the provision of a timer constructed of few parts of rugged construction, and which is accurate, simple, and highly eifective in use.

To these and other ends, the invention resides in certain improvements and combinations of parts, all as will be hereinafter more fully described, the novel features being pointed out in the claims at the end of the specification.

In the drawings:

Fig. l is a side view of the timer of the present invention with the side plate removed, parts in section, and showing the arrangement of the various parts;

Fig. 2 is a front view of the timer showing the relation of the presettable pointer and the timing pointer and the scale plate of the timer;

Fig. 3 is a front View of a portion of the mechillustrated in Fig. 1 and taken just behind the timer scale plate, showing the switch carried by the presettable pointer and the relation of the timing pointer thereto as well as a portion of the drive and return means for the timing pointer; and

Fig. 4 is a wiring diagram of the electrical circuits of the timer.

Similar reference numerals throughout the various views indicate the same parts.

The tim r mechanism itself will first be described after which the operation of the parts in the control of the printer lamps will then be set forth. The timer mechanism is positioned in a suitable housing which may comprise, for examplc, a bottom or support plate Ii, side walls 12, back and front walls is and M respectively, and a top id. The front wall i l may be transparent or may be provided with a transparent section or opening it through which an annular scale plate I? is visible, as best shown in Fig. 2. The scale plate is mounted on the front M, in any suitable manner, and is provided with a circular scale i8 which is divided to represent seconds of time.

The front wall is is provided with an opening 28 in which is positioned a bearing plate 2| for rotatably supporting a shaft 22, the outer end of which has secured thereto a manually-operated control or setting knob 23. The inner end of shaft 22 has mounted thereon a plate 25 which carries a presettable pointer 25 adapted to be moved across the scale E8 to indicate a predetermined or pro-selected time interval, as illustrated in Fig. 2. The position of pointer 25 is controlled by the rotation of knob so that by moving the knob the pointer may be adjusted to any desired position on the scale is to designate the time interval of a definite number of seconds. A fiat spring member or 25 is positioned intermediate knob 23 and the outer end of the bearing 2| to retain the knob and associated parts frictionally in any position of adjustment. The operator may thus set the time of operation of the printer merely by turning the knob to position the pointer 3 25 the latter being shown in Fig. 2 positioned to indicate a time of 10? seconds.

A self-starting synchronous electric clock motor Ell is operatively connected to a drive shaft 29 to d We or rotate the later at a constant and uniform speed, for example in clockwise direction, as viewed in 2. A radially extending arm as is connected to shaft by means of a pin Si, or other suitable means, so that the arm will rotate as a unit with the .iart 2Q. One end of arm 38 has journacd therein a shaft 52 on one end of which is mounted a disk 32 having a roughened or so rated sur face 34, the purpose of which construction will be later described. The other end of shaft 3.: carries a pinion 35 which engages a large gear 35 loosely mounted on the shaft as. t will now I be apparent from an inspection of Fig. that if the shaft 29 is rotated and the gear 3t is h ld stationary, the pinion 35 will roll around on riphery oi the gear If, however, the shaft 32 is held rota ion, by means to be 1; described, the pinion will be loelzed to the to gear 36, and the gear wil then rotate a u: with the arm 33 and the pinion will not rotate relative to the gear.

The right face 3? of the gear 35, as viewed in Fig. 1, has mounted thereon a coil spring one end 39 of which is anchored to a sleeve or collar l carried by gear while the other end 4! is anchor d to a bracket :32 carried by and extending upwardly from the bottom i, as shown in Figs. 1 and 3. The collar as has secured thereto a timing pointer &3 of the shape best shown in Fig. 1 adapted to overlie the scale IS, as best shown in Fig. 2. Thus, as the gear 36 is rotated at a constant speed by the shaft is, the pointer it will progressively move over the scale It to indicate a of the time in seconds. Such rotation of the gear 35 also serves to wind up or tension'the spring When, however, the gear 3% is disconnected from the shaft 253, in a manner to be later described, the gear is free and is then rotated in a counter-clockwise direction, under the action of the tensioned spring 218, to return the pointer as to an initial or starting position, such as the zero position shown on the scale it in Fig. 2. Thus the pointer 43 will indicate the lapse of time so long as the gear 36 is connected with shaft 29, but when the gear is disconnected, the pointer will be automatically returned to the zero position. In order to limit such return movement and to bring the pointer 13 to the zero position, the gear is provided with an axially-extending pin it which is adapted to engage the bracket as when the pointer 43 reaches the zero position, thus limiting the movement of the pointer, as will be apparent from an inspection of Fig. 3.

With the abcve-described arrangement, the knob may be rotated to adjust the pointer 25 to the time interval desired, such as 107 seconds as shown in Fig. 2. Then, when the motor 28 is started and the gear 35 is connected with drive shaft 29, the pointer 43 will progressively move over the scale !8, as is apparent. When, however, the pointer registers with the preset pointer 25 to indicate the lapse of the predetermined time, a switch i? is automatically opened to stop the motor and to open the circuit to the printer lamps. The switch ll comprises a pair of contacts 48 and 5.9 carried by the free ends of a pair of metal strips till and the other ends of which are mounted in insulating relation in a block secured to the back of the or plate is, as best shown in Fig. 1. When the 4 pointer 25 is in a zero position, the strips 50 and 5E lie just to the left or the lower portion 53 of the pointer 6.3.

Now as the knob 23 is rotated in a clockwise direction to adjust the pointer 25, the switch ll is similarly rotated so that when the pointer 25 is, for example, in the position shown in Fig. 2, the switch ll will be in the position shown in Fig. 3. Now when the gear 35 and timing pointer 33 are rotated in a clockwise direction, the lower end 53 of the pointer 3, at the lapse of the time interval and when the pointers 25 and i3 register, will engage finally with an extension 55 of the strip Elil to move the latter to the left, as viewed in Fig. 3, to open the contacts 25 and of the switch ll to st the motor and extinguish the printer lamps as ".111 be presently described.

In order that the opening of the switch i' may be utilized to stop the motor 28 and turn off the lights the printer 5?, the various elements are electrically inte "connected as illustrated in Fig. l which shows a pair oi lead-in wires 58 and 59 adapted to be connected to an electric circuit to supply power for the timer. Tlr wires 58 and 55 may, therefore, be broadly considered as a source of power for the timer mechanism. A relay St has one side connected directly to the lead-in wire 58 and the other side connected to wire 59 through a connection Si in which is positioned a normally-opened switch (52. It will now be apparent that if the switch is closed, the relay to will be connected to the wires 55; and E59, and will be energized.

As the relay it is thus energized, the armature 63 thereof will be drawn inwardly or to the left, as viewed in Fig. 4 to close a pair of switches 65 and 65, the latter being connected, in turn, by lead 65 to the normally-closed switch ll above mentioned, which, in turn, is connected by lines El and St to the lead-in wire 58. Thus as soon as the s vitch 62 is closed, a parallel circuit is established through the relay tit, and the switch may be immediately opened, but the circuit through the relay will be maintained so long as switch ll remains closed, as will be apparent from an inspection of Fig. 4. The switch 62 need therefore be operated only momentarily.

The other switch E l is connected by a wire 68 to a wire 69 which, in turn, is connected both to the motor 28 and to the printer 51, as shown in Fig. 4 to energize the motor and turn on the printing lamps. A return line 10 connects the motor to the lead-infill, and is, in turn, connected by a line H to the printer El. Thus the printer and the motor are arranged in a parallel relation but in series with the switch 66 so that the opening of the latter Will disconnect automatically both the motor and printer circuits, as will be apparent from an inspection of Fig. 4.

Thus, the closing of the switch 62 will start the motor 28 and turn on the lights of the printer. In order, however, that the timing may be in proper relation to the lighting of the printer lamps, means is provided for connecting the gear 36 to the drive shaft 29 substantially simultaneous with the closing of switch 62. To this end, a lever E3 is pivoted at 7 3 to the relay and has the upper end 15 thereof bifurcated to engage a collar or sleeve 76 slidably mounted on the shaft 29.

It will be apparent from inspection of Fig. 1 that when the relay t@ is energized by the closing of switch 62, as mentioned above, the lower end i? of lever is will be drawn to the left by the magnet of the relay. Such movement will pivot the lever in a clockwise direction about its pivot 14 to shift the collar 16 to the right. A Z-shaped arm 18 has the lower end rigidly secured to the arm so that the two arms will rotate as a unit with shaft 29. The upper end of arm 18 is provided with a member 19 adapted to engage the serrated surface 34 of disk 33, as shown in Fig. 1. Thus as the collar 151s shifted to the right by lever 13, the arm 18 will be flexed to the right to bring the member l9 into holding relation with the disk 33 to lock the latter, as well as shaft 32 and pinion 35, against rotation. Such locking serves to connect the gear 36 to the arm 36 and hence to the shaft 29. Thus the lever 18, member 19, disk 33, shaft 32 and pinion 35 constitute, in effect, a clutch mechanism for connecting the gear 36 detachably to the drive shaft 29 whenever the switch 62 is closed. When however, the relay 6!) is de-energized by the opening of switch 41, the lever 13 will be moved in a counterclockwise direction by reason of the flexible arm 18 to withdraw the member 19 out of holding relation with the serrated surface 34 to unlock the pinion 35. Such unlocking releases gear 36 and as the latter is now free, it will rotate in a counter-clockwise direction, as viewed in Fig. 3, under the action of the spring 38 until the pin 44 engages bracket 42, at which time the timing pointer 43 has been returned to its zero or initial position as shown in Fig. 2.

Thus the momentary closing of switch 62 serves to connect or clutch the gear 35 automatically to the drive shaft 29 so as to rotate the gear and pointer 43, and also to energize the drive motor 28 and to turn on the printer lights. As the relay is self-energizing, by reason of the switches and 41, the switch 62 need be closed only momentarily. However, at the completion of the time interval the timing pointer 43 has moved into register with the preset pointer 25 so that the end 53 of the pointer 43 would then open switch 41 to thus de-energize the relay and to open switch 64 to interrupt or cut off the motor and printer circuits. Thus the timer may be preset for a desired or predetermined time at the completion of which the circuit to the printer lamps is interrupted automatically to extinguish the lamps.

While one embodiment of the invention has been disclosed, it is to be understood that the inventive idea may be carried out in a number of ways. This application is, therefore, not to be limited to the precise details described, but is intended to cover all variations and modifications thereof formed within the scope of the appended claims.

I claim:

1. An exposure timer comprising, in combination, a scale, a presettable pointer movable relative to said scale to indicate a predetermined time interval, a drive shaft, an electric motor for driving said shaft at a uniform speed, a second pointer freely mounted on said shaft, clutch means for connecting said second pointer in driven relation with said shaft to move said second pointer from an initial position over said scale at a uniform rate, a switch carried by said first pointer for controlling the circuit of said motor, and means controlled by said second pointer for opening said switch at the completion of said interval to open the circuit of said motor to stop the movement of said second pointer.

2. An exposure timer comprising, in combination, a scale, a presettable pointer movable relative to said scale to indicate a predetermined time interval, a drive shaft, an electric motor for driving said shaft at a uniform speed, a second pointer freely mounted on said shaft, clutch means for connecting said second pointer in driven relation with said shaft to move said second pointer from an initial position over said scale at a uniform rate, a switch movable with said presettable pointer for controlling the circuit of said motor, means controlled by said second pointer for opening said switch at the completion of said interval to open the circuit of said motor to stop the movement of said second pointer and to disengage said clutch means to disconnect said second pointer from said shaft, and means to return the disconnected pointer to said initial position.

3. An exposure timer comprising, in combination, a scale, a presettable pointer movable relative to said scale to indicate a predetermined time interval, a drive shaft, an electric motor for driving said shaft at a uniform speed, a second pointer freely mounted on said shaft, clutch means for connecting said second pointer indriven relation with said shaft to move said second pointer from an initial position over said scale at a uniform rate, a relay, means for controlling the circuit of said motor from said relay, a normally-open, momentarily-operated switch arranged in the circuit of said relay so that the momentary closing of said switch will serve to energize said relay and simultaneously to operate said controlling means to close the circuit of said motor, said switch being then opened upon the closing of the motor circuit, a normally closed switch adjustable with said presettable pointer and arranged in the circuit of said rela and rendered operative upon the closing of said first switch to complete the circuit through said relay to retain the motor circuit in a closed condition, and means controlled by said second pointer for opening said second switch at the completion of said interval to open the circuit of said relay to render said control means inoperative so as to open the circuit of said motor to stop the latter.

4. An exposure timer comprising, in combination, a scale, a presettable pointer movable relative to said scale to indicate a predetermined time interval, a drive shaft, an electric motor for driving said shaft at a uniform speed, a second pointer freely mounted on said shaft, clutch means including a slideable member on said shaft for connecting said second pointer in driven relation with said shaft to move said second pointer from an initial position over said scale at a uniform rate, a relay, a source of power, a normally-open switch arranged in the circuit of said relay and momentarily closable to energize said relay, a pair of switches operatively connected to said relay and moved to closed position when said relay is energized, one of said pair of switche being arranged in the circuit of said motor to connect the latter to said source of power when said relay is energized, a normally closed switch adjustable with said presettable pointer and arranged in series with the other of said pair of switches and connected into the circuit of said relay when said pair of switches are closed to close the circuit through said relay upon opening of said first switch, and means controlled by said second pointer for opening said normally-closed switch upon the completion of said interval to simultaneously open the circuits to said relay and motor.

5. In a photographic apparatus, the combination with a photographic printer, of an exposure timer, said timer comprising a scale, a presettable pointer movable relative to said scale to indicate a predetermined time interval, drive means including a constant-speed electric motor, a second pointer, a source of power, a relay, a normallyopen switch adapted to be closed momentarily to connect said relay to said source of power, means controlled by said relay for connecting said second pointer to said drive means, a pair of switches operatively connected to and adapted to be closed when said relay is connected to said source of power, one of said switches being arranged in the circuit of said motor and printer to connect the motor and printer to said source of power, a normally-closed switch carried by said-presettable pointer and arranged in series with the other of said pair and adapted to complete the circuit through said relay when said first switch is reopened, and means controlled by said second pointer for opening said normally closed switch at the completion of said interval to open the circuit to said motor and printer.

6. In a photographic apparatus, the combination with a photographic printer, of an exposure timer, said timer comprising a scale, a presettable pointer movable relative to said scale to indicate a predetermined time interval, drive means including a constant-speed electric motor, a second pointer, a source of power, a relay, a normallyopen switch adapted to be closed momentarily to connect said relay to said source of power, means controlled by said relay for connecting said second pointer to said drive means, a pair of switches operatively connected to and adapted to be closed when said relay is connected to said source of power, one of said switches being arranged in the circuit of said motor and printer to connect the motor and printer to said source of power, a normall closed switch opcratively connected to and movable as a unit with said presettable pointer and arranged in series with the other of said pair to maintain the circuit and said relay in closed position when said first switch is reopened, and means movable with said second pointer for engaging and opening said normally-closed switch at the completion of said interval to open the circuit to said motor and printer.

'7. In a photographic apparatus, the combination with a photographic printer, of an exposure timer, said timer comprising, a scale, a presettable pointer movable relative to said scale to indicate a predetermined time interval, drive means including a constant-speed electric motor, a second pointer, an electric circuit, a switch for connecting said circuit to said motor and printer, a control circuit in parallel relation to said first circuit, a relay in said second circuit, means operated by said relay for connecting said second pointer to said drive means to be moved thereby, a norma'ilywpen, momentarily-operated switch adapted to be closed to energize said relay, means controlled by said relay for closing said first switch to complete the circuit to said motor and printer, another switch adapted to be connected in series with said relay when the latter is energized, a normally-closed switch carried by and movable with said presettable pointer and arranged in series with said other switch to complete the circuit through said relay to maintain the latter operative when said normally-open switch is reopened, and means carried by said second pointer adapted to engage and open said normally-closed switch at the completion of said interval to open said other switch to de-energize said relay to disconnect said second pointer from said drive means and to open the switch in the motor and printer circuit,

8. In a photographic ap aratus, the combination with a photographic printer, of an exposure timer comprising a scale, a presettable pointer adjustable relative to said scale to indicate a predetermined time interval, drive means including an electric motor and a drive shaft connected to said motor, a gear loosely mounted on said shaft, a timing pointer connected to said gear for rotation as a unit therewith, a radially extending arm fixed to said shaft adjacent said gear, a shaft rotatably carried by said arm adjacent the outer end thereof, a pinion fixed on said second shaft and meshing with said gear, said pinion being adapted to roll on said gear when said arm is moved upon rotation of said first shaft, means for holding said secondshaft against rotation to lock said pinion to said gear so that the latter will rotate with said arm to move said timing pointer over said scale, a switch carried by said presettable pointer and arranged in the circuit of said motor, and means on said timing pointer for opening of said switch at the end of said interval to open the circuit to said motor to stop the latter.

9. In a photographic apparatus, the combination with a photographic printer, of an exposure timer comprising a scale, a presettable pointer adjustable relative to said scale to indicate a predetermined time interval, drive means including an electric motor and a drive shaft connected to said motor, a gear loosely mounted on said shaft, a collar carried by said gear, a timing pointer connected to said collar for movement as a unit with said gear, a radially extending arm fixed to said drive shaft adjacent said gear, a shaft journaled in said arm adjacent the outer end thereof, a pinion fixed to said second shaft and engaging said gear for rolling movement thereon, a disk fixed to said second shaft, means controlled by the starting of said motor for engaging said disk to hold said second shaft against rotation relative to said arm to lock said pinion to said gear so that the latter and said timing pointer will rotate as a unit with said arm to move said timing pointer over said scale, a switch mounted on said presettable pointer and arranged in the circuit of said motor, means on said timing pointer for engaging and opening said switch at the end of said interval, means operative upon the opening of said switch for releasing said disk to unlock said pinion from said REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,157,300 Dempster Oct. 19, 1915 2,053,143 Frederick Sept. 1, 1936 2,143,592 I-Iaar Jan. 10, 1939 2,163,419 Warren June 20, 1939 2,459,876 Gibson 1 Jan. 25, 1949

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