US2059925A

US2059925A - Timing apparatus

Info

Publication number: US2059925A
Authority: US
Inventors: Harry J Atticks
Original assignee: Individual
Current assignee: Individual
Priority date: 1933-07-06
Filing date: 1933-07-06
Publication date: 1936-11-03
Anticipated expiration: 1953-11-03

Description

3 Sheets-Sheet l ll Illlll H. J. ATTICKS TIMING APPARATUS Filed July 6,

Nov. 3, 1936.

Nov. 3, 1936. H. J. ATTlcKs 2,059,925

TIMING APPARATUS Filed July 6, 1935 I5 Sheets-Sheet 2 Nov. 3, 1936. H. J. A'r'rlcKs 2,059,925

TIMING APPARATUS Filed July 6,1935 s sheets-sheet 3 Jw/ '42?! i@ J0 Patented Nov. 3, 1936 'UNITED STATES PATENT OFFICE Harry J. Atticks, Mechanicsburg, Pa.

Application July 6, 1933, `Serial No. 679,257

5 Claims.

The invention relates to a variable timing apparatus adapted to close the operating circuit of a translating device or mechanism and maintain the closure for a predetermined and selected 5 time interval, the breaking of the circuit being effected by a synchronous or constant speed motor, which operates an adjustable trip, which, at the end of the selected time intervaL-releases the switchv from the locking means actuated 1o simultaneously with the closing of the switch, with means for resetting the trip to its initially adjusted position, so that the translating device may be' operated repeatedly for each selective setting of the apparatus and the duration l5 of each operation may be accurately regulated as to time.

The invention isy illustrated in the accompanying drawings, in which:-

Fig. l is a side elevation, partly in section, of

Q the apparatus with the cover removed.

Fig. 2 is a plan view. v

Fig. 3 is a section on line 3-3 of Fig. 1.

Fig. 4 is an enlarged horizontal section showing certain details.

Fig. 4L1 is an elevation of the spring motor.

Fig. 5 is a section on line 5-5 of Fig. 4.

Fig. 6 is an enlarged side elevation of part of the trip device.

Fig. 7 is an end elevation thereof.

50 Fig. 8 is a perspective view of the entire apparatus, including the casing.

Fig. 9 is a general perspective of the principal operating parts of the mechanism.

Fig. 10 is a diagram of the circuits.

Fig. 11 is a front elevation of a shutter operating device adapted to be operated by the timing apparatus.

Fig. 12 is a lateral sectional elevation of the same.

40 Fig. 13 is a plan view thereof.

Referring to 'the drawings, indicates the base of the apparatus, which is formed as a hollow casting having secured to the inner face of its top a block of insulation in which is 45 mounted the binding posts or connectors for the various circuit leads. Secured to the top surface of the base is a framework comprising front and

rear plates

2 and 3, which are connected together by cross bolts 4. Supported by 50 spacer members 6 and channels 5 is a glass panel 5, which is parallel with the front plate 2, and serves to protect the indicia carried by the front plate, as will be pointed out hereinafter. Associated with the base I and the frame 55 carried therebyis a cover provided with a,

front sight opening 8 and a handle 9, which is secured to the top and extends downward and is locked to the base by nuts engaging the threaded ends of the handle.

Secured by spacer bolts to the rear plate 3 5 is a synchronous or constant speed motor I0, which is preferably of the type commonly employed in electric clocks operated by alternating currents of commercial circuits, the motor driving a chain of reducing gearing, the final mem- 1U ber I2 of which meshes with a pinion I3 fixed to shaft I4 journaled in the

plates

2 and 3 and carrying on its forward end a hand or index I5, which corresponds to the second hand of a clock and associated with a dial I6 on the front 15 plate 2, said dial having a seconds scale thereon, the motor driving'the shaft 4 at the rate of one complete revolution thereof per minute, so that the hand I5 travels around the dial I6 once every minute. zu

Secured to the back plate 3 are spaced brackets 2|, 2| connected together by tie rods 22, between which brackets is mounted a solenoid provided with a surrounding casing or armor 20. Cooperating with the solenoid 20 is a core 23, to 25 the upper end of which is attached a rod 24 extending through an opening in the top bracket 2| and carryig on its threaded end set nuts 25, which limit the downward movement of the core 23. Pivoted to the lower end of the core 23 is a 30 link 26, the lower end of which is, in turn, pivoted to a rock lever 21 fixed to a longitudinal shaft 28 journaled in bearings in the lower portions of the front and

rear plates

2 and 3, as more pariicuiariy illustrated in Fig. 1. The lever 21 is 35 connected to link 29, which is connected to the outer end of a rock lever 30 secured to a sleeve 3| loosely mounted on the shaft I4, said sleeve having secured to its forward end a plate 32 provided with spring clips 33, 33, which support the tubular member 34 of a mercury switch, which tubular member is provided with two

downward extensions

35 and 35 in which are sealed the ends of circuit wires, the parts being so arranged that, when the solenoid is energized and the core 23 elevated, the tube of the mercury switch will be locked in the position shown in Fig. 3, so that the body of mercury inthe main part of the tube will bridge the smaller bodies of mercury in the nipple-like extensions 35 and 35' and close the circuit between the wires sealed in said extensions, thereby closing the circuit from the source of electric current to the translating device or mechanism, which is to be operated for a predetermined time, as will be more particularly explained hereinafter.

Mounted on a lateral extension of the upper bracket 2| is an insulating block 35, to which is secured two leaf spring terminals 31 and 31' interposed in one of the main circuit leads to the solenoid 20, which Jterminals are adapted to be bridged by a metal pin 4| mounted in a rock lever 48 secured to a shaft 38, which isl journaled in the

plates

2 and 3, respectively, said rock lever 48, leaf spring terminals 31 and 31 and bridging contact 4| constituting a switch or circuit breaker to interrupt the circuit of the solenoid, when the core 23 of the latter has completed its upward movement, as will be more particularly described hereinafter.

Secured to the rear plate 3 by spacer bolts 45* is a casting comprising a generally triangular plate 45 having formed integrally therewith a cylinder 41 disposed in horizontal relation and extending toward the front plate 2, the forward end of said cylinder having a central opening therein. The end of the casting toward the rear plate 3 is closed by a casing 45', which is secured to the plate 45 by screws and has projecting from its inner face and located axially within the cylinder 41 a hollow boss 48 provided with screw threads on its outer surface, which screw threads are engaged by a threaded nut 49 having gear teeth 58 on its periphery and also having a forward helical extension 5|, which constitutes a yielding stop or detent. Extending through the central opening in the casing 45 is a sleeve 52, which is pinned to a longitudinal shaft 53, the forward end of which is journaled in the front end of the screw threaded boss 48. The pin connecting the sleeve 82 to the shaft 58 also secures thereto and to the shaft a clutch disk 54, the operating face of which is preferably serrated and is adapted to cooperate with a washer of leather or other flexible material mounted in the coordinate face of cooperating clutch member 55, which is loosely journaled on the shaft 53, said clutch member being provided with a toothed gear 56, which meshes with the gear I2 in the train of gearing driven by the synchronous motor I0, as hereinbefore described. The rear face of the lclutch member 55 is provided with an inwardly beveled face 51 with which cooperates the coned or beveled head 58 of a sleeve 58', said head 58 also constituting a collar by means of which the clutch member 55 is released from engage ment with clutch member 54. The sleeve 58 telescopes with an exteriorly threaded thimble 5I, which is adjustably mounted in an interiorly threaded socket 5|) secured to the outer face of the rear plate 3 and is locked in adjusted position by a set nut 62. 'I'elescoping in the sleeve 58 is a bushing 63 having a beveled shoulder which engages a beveled shoulder on the interior of thimble 6|, when the clutch members are disengaged, and an interiorly beveledend engaging the coned end of a nut E5, on the threaded end of shaft 53, when the clutch is in engaged relation, said nut being held in adjusted position by set nut 66. The bushing 53 serves as the outer abutment for a helical spring 64 which surrounds shaft 53 and snugly engages the inner wall of sleeve 58', the opposite end of said spring. abutting the head 58, so that the normal tendencyr o! the spring is to force clutch member 55 into engagement with member 54 and couple shaft 58 to the motor I8, The outer end of the shaft 58 is Journaled in a bracketi secured to the rearplate 3. This particular coordination constitutes means for normally engaging the

clutch members

54 and 55 with each other through the action of the spring 64, but which will permit the clutch member 55 to rotate freely, when disengaged from clutch member 54, without imposing any undue stress on the motor spring |06, hereinafter described. While there is no positive connection between the head 58 and the clutch member 55, it is found, in actual practice, that the movement of the sleeve 58' to disengage the clutch members will effect this result apparently by reason of the slight cohesive effect of the lubricant between the coned surface of the head 58 and the beveled recess 51 in the clutch member 55.

Secured to the forward end of the shaft 53 is a cage-like element comprising annular members 81 connected by a series of bars 58 and slidably mounted on the bars 58 is a nut 59 having a radially projecting arm 10. The forward end of the cage-like element is journaled on the boss 12 formed as an integral part of a screw th'readed stud 1|, which is fixed in a plate 14 closing the forward end of the cylinder 41, said screw threaded stud being secured in position by nut 13. The nut 88 engages the threads on the stud 1| and, as the latter is stationary, the rotation of the nut 88 will cause the latter to move axially of the stud 1| so that one complete rotation of the shaft 53, when driven by the synchronous motor i8, and, therefore, one complete rotation of the nut 58 on the stud 1| will be eil'ected in one minute. Normally the outer end of the radial arm 10 rests against the end of the helical extension 5| of the toothed nut 48, which is mounted on the threaded boss 48 and is moved out of engagement with the end of said helical member, when the shaft 5I is driven by the motor l0. The adjustment 0f the toothed nut 48 on the threaded boss 48 determines the extent of travel of the `nut 88 on the threaded stud 1|, when the shaft 53 is connected to the motor I8 by engagement of the

clutch members

54 and 55, the projecting member I8 of the nut 58 constituting the effective element 0i' a trip device, which accurately determines the period of time during which the mercury switch maintains the circuit to the translating device closed.

As it is characteristic of the apparatus that only a momentary closure ofthe energizing circuit to the solenoid is necessary, means are provided for locking the mercury switch in its circuit closing position and also holding the core of the solenoid in its upper or attracted position. To effect these operations, there is fixed to the shaft 28 a crank arm 80, which is connected by link 8| with a rock lever 82, which is fixed on shaft 38, said rock lever carrying near its outer end a stop or detent 83 projecting laterally therefrom, which is adapted to be engaged by the upper end of a bell crank lever 1E pivoted on a collar 15 clamped about the end of the cylinder 41, which lever is actuated by a spring 11, which moves the upper end of the bell crank lever under the detent 83, when the latter is elevated, thereby holding said rock lever 82 in its elevated position and locking the mercury switch in its circuit closing position and also retaining the core of the solenoid in its elevated position. The opposite end of the bell crank lever 18 projects through an opening in the cylinder 41 into the path of movement of the lug or trip member 10 of the nut 89, so that. when the nut is advanced along the screw threaded stud 1| and simultaneously rotated on said stud, the trip lug 18 ultimately engages the end of the bell crank lever 16 and rocks the same against the tension of the spring 11 to move the upper end of said bell crank lever out of engagement with said detent 83, thereby permitting the weight of the core 23 of the solenoid to move rock lever 21 downward which imparts a partial rotation to shaft 28 and also to crank arm 30 and sleeve 3|, which causes the mercury switch to tip in the opposite direction and break the circuit to the translating device controlled by said switch.

Fast to the shaft 28 is a rock arm 85 adapted to engage the laterally bent arm of a rock shaft 86 journaled in bearings 81 secured to the rear plate 3 and having fast thereon a yoke 88, which engages the collar formed on the head 58 of the sleeve 58', Normally the rock arm 85 engages the rock shaft 86 to force the sleeve 58 against the tension of spring 64 to uncouple the

clutch members

54 and 55, thereby disconnecting shaft 53 from the motor l0. When, however, the solenoid 20 is energized, rock arm 85 is partly rotated, together with the shaft 28, thereby releasing the pressure on the bent end of the rock shaft 86 and permitting the spring 64 to force the clutch member 55 into engagement with clutch member 54 and coupling the shaft 53 to the motor |0.

The apparatus is provided With-means for setting the same to retain the mercury switch in closed relation during predetermined time intervals, so that the length of time which the translating device, connected with said mercury switch, is operated, may be accurately'determined and regulated. The setting device includes a shaft 9|), which is journaled near one end in a bearing in the plate with its other end projecting through the front plate 2 and through an opening in the glass panel 5, said shaft being provided on its outer end with a knob 9| and having mounted on the squared section thereof inside the glass panel a hand or pointer 92, which cooperates with a seconds scale ||1 on the front plate 2, said shaft driving a train of clock gears indicated as a whole by' the reference numeral 93, the nal gear of said train having mounted thereon a minute hand 94, which cooperates withaminute scale ||8 on the fro-nt plate 2. Fixed to the shaft 90 is a broad faced gear 96, which projects through an opening in the cylinder 41 and engages the gear teeth on the periphery of the nut 49, which latter is in threaded engagement with the threaded boss 48, so that, when the shaft 90 is rotated, the gear 96 drives the gear nut 49 and causes the latter to traverse the threaded boss 48 axially. thereby moving the nut 49 and its helical detent 5| longitudinally of the cylinder 41 and determining the rest position of the trip lug 10 on nut 69. The number and pitch of the threads on the axial boss 48 corresponds with those on the threaded stud 1|. One complete rotation of the nut 49 will change the setting of the trip linger 10 by just one minute, as the

gears

96 and 50 have the same number of teeth and accordingly any partial rotation of the shaft will change the setting of the trip device by a given number of seconds indicated by the hand 92 and the markings on the outer dial ||1.

In order to hold the shaft 90 in its position of adjustment and to prevent. accidental displacement of the same, which would result in changing the time of operation of the apparatus, the gear 96 is provided on its inner face with a countersink 91, which engages the beveled face of a pad of leather or the like, which bears against the face of the plate 45. Fixed to the shaft on the opposite side of the plate 45 is a friction pad or washer |00 of leather or the like, which is engaged by a collar 99, which is forced against the element |00 by a helical spring |0| mounted on the inner end of the-shaft 90 and adjusted as to tension by means of set nuts |02. This forms an effective clamp, which, while permitting the shaft 90 to be readily rotated by hand, will prevent any accidental movement of the shaft.

Mounted in the casing 45' is a spiralvspring |06, one end of which is attached to the sleeve 52 by means of a collar 52' having a hexagonal opening engaging a hexagonal section of sleeve 52 and the other to the inner wall of the casing, said spring constituting means for rotating the shaft 53 in a direction opposite to that imparted to said shaft by the synchronous motor I8, said spring motor serving to return the trip arm 10 on the nut 69 to engagement with the end of the cushioning stop or detent 5| whenever the motor is disconnected from shaft 52 by separatic-n of the

clutch members

54 and 55.

In order to indicate the number of operations of the timing device, the latter is provided with an integrating meter or register ||9 of conventional type, mounted on the rear face of the front plate, so that the indicating disks will be visible through an opening in said front plate. This register is operated by the crank arm the outer end of which is connected by lift rod ||2, which passes through an opening in the end of rock lever 82, said lift rod having a detent ||3 thereon which is engaged by said rock lever whenever the latter is elevated, so that the register will be advanced one number for each operation ofthe apparatus. l

As shown in Fig. 3, a gear 93', journaled on a stud mounted in the front plate 2, meshes with the first gear of the clock train 93 and is provided With a stop lug 46, which cooperates with a pin or detent 95 mounted on plate 2, said lug 46 serving to stop the rotatio-n of the knob 9| at -both the upper and lower limits of the time setting mechanism as indicated by the second and

minute hands

92 and 94 on the dial scales and ||8. The movement 0f the knob 9| to bring the dial hands to stop or zero setting causes gear 96 to rotate and advance nut 49 on screw threaded boss 48 and the helical stop or detent 5| on said nut engages trip arm 10 and rotates and advances nut 69 on the threaded stud 1|, so that, at the exact zero setting, the arm of bell crank 16 will just clear detent or stop 83 on arm 82. Preferably gear 83 is so adjusted that the stop lug 46 engages pin 95, when knob 9| has moved the hands 92 and 94 a slight distance to the left of the zero position in resetting the apparatus, so that the trip arm will engage the bell crank 16 and prevent the same functioning, but, when an exact zero setting is effected, by turning the knob a slight distance from the stop position in a clockwise direction. the trip arm 10 will be moved out of contact with the bell crank, so that the latter may be operated in carrying out its normal function in locking the mercury switch in its closed position, when the timing mechanism has been properly set and the electromagnet 20 is momentarily energized.

The apparatus is also designed to operate an ancillary translating device, such as a shutter operating device for photographic apparatus, said device being illustrated in Figs. 11, 12, and 13. This device comprises a bracket |50 carrying a block |54 on the sides of which are mounted two solenoids |5| and |52 having a common core |53,

slidably mounted in a transverse opening in the block |54 and having rack teeth |53' formed on its midsection, which engage a pinion |55 fast on a shaft |55"journaled at one end in a bearing in block |54 and at its opposite end in a bushing |51 threaded into an enlarged opening in the front face of the block. Fixed to the outer end of shaft |55 is a disk |58 carrying a crank pin |59 to which is attached one end of a connecting rod |50, the other end of which is pivoted to a piston or plunger |5| operating in cylinder |52 extending from bracket |50, said cylinder having on its lower end a nipple |53 adapted to be connected by a flexible tube to a conventional photographic shutter. As shown, the travel of the solenoid core will carry the crank pin |59 somewhat beyond the dead center in both the upper and lower positions of said crank pin, so that accidental actuation of the piston |5| is prevented.

As conventionally illustrated in Fig. l0, the electromagnet 20,'the primary translating device, represented by lamp |28, and the shutter operating device, are energized by current from the main leads |20, |2| of an ordinary commercial supply of electric current. Motor I is connected directly across main leads |20, |2I. The circuit of the magnet 20 is from main lead-|2l, lead |22, momentary switch |25, lead |23, coil of magnet 20, lead |24, contact 31', pin 4|,\contact 31, lead |25 to main lead |20. The circuit of the lamp is from main lead |2|, lead |25 to terminal 35 oi mercury switch through the mercury to terminal 35, lead |21, lamp |28, lead |29 to main lead |20. The circuit of solenoid is from main lead |2I, lead |22-, switch |28, lead |30, coil of solenoid |5I, lead |3|, lead |32, contact 31', pin 4I, contact 31, lead |25 to main lead |20. The circuit of solenoid |52 is from main lead |2|, lead |25', mercury switch, lead |21, lead |33, coil of solenoid |52, leads |3|, |32, contact 31', pin V4|, contact 31, lead |25 to main lead |20. As solenoid |52 is energized at the time the circuit of lamp |28 is broken at the mercury switch, it isl necessary that the circuit be completed between contacts 31 and 31 before it is interrupted at the mercury switch, and the initial movement of rock lever 82, when the latter is released, effects the closing of the circuit at said contacts 31, 31 by pin 4| and, as the breaking of the circuit at the mercury switch is not effected until the end of the release-movement of the core of magnet 20 and the linkage connecting the same with rock lever 82, the opening of the circuit at the mercury switch occurring after the closing of said circuit at contacts 31, 31'. The time interval between the closing of the circuit at contacts 31, 31' and the breaking of said circuit at the mercury switchis increased somewhat by the time required for the body of mercury to flow from one end to the other of the tubular container, so that there is an appreciable lag in the action of the mercury switch and, as a momentary energization of solenoid 52 is all that is required, the said solenoid will attract core |53 and reverse the action of the shutter operating device before the circuit is broken at the mercury switch.

The operation of the apparatus is as follows: The knob 9| is turned in a clockwise direction to bring the pointers controlled thereby in registry with the desired time interval on the minute and seconds dials. If the desired time interval is measured in seconds, it will be indicated by turning the knob for a partial rotation until the pointer is opposite the 'proper index on the seconds dial. Should the ltime interval be measured in minutes and fractions thereof, the knob is rotated until the minute hand 94 indicates the number of minutes and the second hand the number of seconds in addition. When the timing device has been thus set, the switch |28 is closed momentarily either manually or by the movement of some part of the mechanism of the translating device with which the timing apparatus is associated. For example, if the apparatus is employed for timing photographic printing, the switch |26 may be momentarily closed during the closing movement of the printing frame by engagement of said frame or an element connected therewith with the moving element of the switch, as will be understood by those familiar with the art. The closing of the switch |25 energizes solenoid 20, drawing up the core 23 and raising rock lever 21, which imparts a partial rotation to shaft 28, which, in turn, moves rock lever 30 through link 29 and tilts the mercury switch, connected to said rock lever 30, to cause the mercury to bridge the contacts in the switch terminals 35 and 35', thereby closing the circuit to the lamp |28. The movement of rock shaft 28 imparts a similar rocking movement to shaft 38 through crank arm 80, link 8| and lever 82 secured to said shaft 38, elevating the outer end of the rock lever 82 ancl permitting the upper end of bell crank 15 to pass under the stop or detent 53 on the lever 82, thereby locking the several elements referred to, including the mercury switch, in their adjusted positions. The rocking movement of shaft 38 moves the switch arm 4l) to disengage the bridging contact 4| with the stationary contacts 31 and 31', thereby interrupting the circuit of the solenoid, so that the latter will be deenergized even if the switch |25 is left closed. The movement of rock shaft 28 causes rock arm 85 to relieve pressure on the horizontal arm of rock shaft 85, permitting the spring 54 to force the clutch member 55 into engagement with clutch member 54, thereby coupling the motor I0 to the shaft 53, as hereinbefore explained. Therotation of the shaft 53 causes the cage-like element secured to the end thereof to rotate therewith, thereby rotating the nut 59, which, by reason of its screw threaded engagement with the stud 1|, moves axially along said stud until the trip arm 10 'on said nut 89 engages the end of the bell crank lock and rocks said bell crank against the tension of the spring associated therewith and moves the upper end of said bell crank out of engagement with the detent 83 on the rock lever 82. This unlocks the entire mechanism and permits the weight of the solenoid core to reverse the movement of all of the parts connected therewith, including lever 21, rock shaft 28, rock shaft 39` and the mercury switch, which latter is tilted to break the circuit through the lamp. 'I'he reverse movement of rock shaft 38 causes the switch arm 40 to move to engage the bridging contact 4| with the terminals 31 and 31', thereby restoring the break in the solenoid circuit at this point. The reverse rocking movement of the shaft 28 causes rock arm 85 to engage the lateral arm of rock shaft 85, which causes the yoke 88 to move sleeve 58 against the tension of spring 84, thereby releasing the clutch member 55 from engagement with clutch member 54 and disconnecting the motor I0 from shaft 53, which latter is now free toA rotate in the opposite direction and is so rotated by the spring motor |08. This reverse rotation of the shaft 53 causes a similar rotation ofthe hut 69 on the threaded stud 1| and also an axial movement of said nut because of the threaded engagement between the same and the stud until the trip arm 10 on said nut 69 engages the end of the resilient detent formed on the toothed nut 49. The upward movement of the rock lever 82, during the operation of closing the mercury switch, actuates the lift rod |l2, which, in turn, actuates the register ||9 to indicate the particular operation.

When the timing apparatus is employed to operate a second or ancillary translating device, such, for example, as the shutter actuating mechanism, the closing of the momentary switch |26` energizes solenoid |5I, causing the same to attract its core, and the movement of the latter imparts a partial rotation to gear |55 and crank disk |58, thereby lifting piston |6| in cylinder |62 and applying suction to the shutter to open the same in the conventional manner, the circuit of said solenoid |5| being broken by the movement of rock lever 40 to withdraw contact pin from engagement with terminals 31, 31'. 'Ihe shutter remains open until the mercury switch is released by the trip device at the end of the predetermined time interval to which the apparatus is adjusted, when the initial return movement of rock lever 38 causes contact pin lil-to engage contacts 31, 31', thereby closing the circuit of solenoid |52, as before described, causing said solenoid to attract core |53, which rotates pinion |55 and crank shaft in the opposite direction, forcing piston |6| downward in cylinder |62, which is eiTective to close thc shutter. This circuit is closed only momentarily and is broken at the mercury switch as soon as the latter completes its opening movement, but the lag of the said mercury switch, due to the inertia of the body of mercury therein, allowsthe circuit to remain closed for av suiiicient period of time to energize the solenoid |52.

It will be understood that the application of the timing apparatus to operate the shutter actuating device is merely exemplary and that it may be employed to operate many other forms of translating devices.

The particular form of the apparatus shown is capable of effecting extremely accurate timing of the operations of translating devices of various kinds that are to be actuated for predetermined time periods varying from a few seconds to as long as five minutes, the operations of the translating device being susceptible of indefinite repetition without any variation in the time intervals whatever, as the latter are controlled and regulated by the accurate adjustment of the nut 49 on the threaded boss 28, which fixes the starting point of the trip arm 10, and a similarly accurate adjustment of the nut 69 and the movement thereof on the threaded stud 1|, which movement is effected by the shaft 53, which, in turn, is driven by the synchronous motor I0.

This application is a continuation in part of application Serial No. 574,142, filed November 10, 1931, for Automatic electric time elapsed control mechanism. l

What I claim is:

1. A timing apparatus, comprising a switch for closing an electric circuit of a translating device to be timed, an electromagnet for moving the switch to circuit closing position, locking means for maintaining the switch in closed position independent of the energization of the electromagnet, trip mechan sm for moving the locking meansv to inoperative position to permit movement of the switch to open position, said locking means being movable into operative position upon movement of the switch to circuit closing position, means for moving the trip mechanism to an adjusted position so as to operate at the end of a predetermined time interval following the closing of the switch, a substantially constant speed motor, a clutch for connecting the motor to the trip mechanism to advance the same while the switch is closed, and means for retracting the trip mechanism to its adjusted position after each tripping operation.

2. A timing apparatus, comprising a switch for closing an electric circuit of a translating device,

1 an electromagnet for moving said switch to circuit closing position, means for locking the switch in closed position and time controlled means for releasing said locking means, said time controlled means including a constant speed motor and a rotary and axially movable member operable thereby for moving said locking means to releasing position.

3. A timing apparatus, comprising a switch for l`closing an electric circuit of a translating device,

an electromagnet to move said switch to circuit closing position, means for locking the switch in closed position, trip mechanism for releasing said locking means including a rotary and axially movable member cooperable with said locking means, a constant speed motor for actuating said member, means for retracting said memberafter each tripping operation, and an adjustable stop to limit the return movement of said member.

4.= A timing apparatus as described in claim 1, including means for momentarily closing the circuit of the electromagnet and additional means operable by the magnet independently of said motor for interrupting the circuit of said magnet upon completion of the switch closing operation.

5. A timing apparatus for translating'devices, said apparatus comprising means for momentarily closing an electric circuit of the translating device for causing said device to effect one operation, a switch for closing a second circuit of the translating device for causing said device to effect another operation, an electromagnet for effecting movement of said switch to circuit closing position, means acting after a predetermined interval for opening said switch, and a second switch common to both of said circuits and controlled by the electromagnet for opening the flrst named, circuit during circuit closing movement of the first named switch, said first named switch having a lag in its opening and closing movement relative to the respectively opposite movements lof said second switch, whereby in the cycle of operation of said apparatus said second switch opens before therst named switch closes and the second switch closes before the first switch opens.

HARRY J. ATIICKS.