US2141495A - Electric clock - Google Patents

Description

De.27,193s. ,ETTURNEY- y 2,141,495

y ELECTRIC CLOCK Filed Feb. 24, 1937 .ZZ EUGENE rra/@MSV INVENTOR A ORNEY Patented Dec. 27, 1938 *UNITED STATES PATENT ori-ics ELECTRIC CLOCK Eugene T. Turney, Holmes, N. Y., assignor to Eugene T. Turney, Jr., New York, N. Y.

Application February 24, 1937, Serial No. 127,361

A2 Claims. (Cl. 185-40) The invention disclosed herein relates to electric timepieces.

Special objects of the invention are to provide a clock construction, which will operate accu- 5 rately rand reliably on either alternating or direct current, which may be readily combined' with existing forms of clock movements and which will consist of but few simple and inexpensive parts. Further special objects are to provide clock actuating means, which will be highly eiicient electrically and will require but small electrical energy.

The vforegoing and other desirable objects are attained in this invention by the novel features of construction, combination and'relations of parts hereinafter described, illustrated in the accompanying drawing and broadly covered in the claims.

Y Y In the drawing,'there is-shown one practical commercial embodiment of the invention, but it is to be understood that the structure may be varied within the true intent and broad scope of the invention as hereinafter defined and broadly covered in the claims.

Fig. 1 is a broken rear View of one form of the invention as applied to an ordinary clock escapement.

Fig. 2 is a vertical sectional view as on'substan- 3Q tially the plane of line 2-2 of Fig. 1.

Fig. 3 is a broken part sectional enlargement of the main parts of the device.

In the illustration, a clock movement is indicated at 5, consisting in general of an escape- ,35 ment mechanism 6, at one end and a ratchet wheel l, at the opposite end of a short gear train.

The drive is effectedr through a gravity lever 8, shown as pivoted to swing about the center 9, of the ratchet and carrying a drive pawl Il),

40 engaging the teeth of the ratchet.

The ratchet lever is forced downwardly by a weight consisting in the illustration of a solenoid core II, of ilat laminations operating vertically up through the narrow rectangular guide passage 45 I2, in the solenoid winding I3, and loosely pivotally connected at its lower end with the lever at I4. A spring pawl is indicated at I5, for holding the drive ratchet against reverse motion in the retractive or recovery movements of the 50 gravity actuated ratchet lever.

Energization of the electromagnet is effected in the present disclosure from a small mercury switch indicated at I6, and shown as carried by a swinging bracket I1, pivoted at I8, over a con- 55 tact plate I9.

The mercury switch and necessary electric terminals and contacts are shown as all carried by a plate v20, of insulating material secured to the back of the clock movements by screws 2l. Y

The terminals for the external circuit wires g5z 22, 23, are indicated at 24 and 25. From the first of these terminals', a wire 26, is indicated extending across the back of the insulating base to a terminal 2l, from which a flexible conductor 28, extends to one of the mercury switch 10 terminals 29. From the other switch terminal 30, a conductor 3|, extends to the switch bracket I 7, and this side of the circuit then continues through contact I9 and wire 32, to one end of the solenoid coil. The opposite end of the sole- 15 noid coil is simply connected by a lead 33, -to circuit Vterminal 25.

From the latter description, it will be seenthat when the globule of mercury 34, in the switch tube engages switch contacts 29, 30, circuit will 20 be established through the magnet winding to 'effect the lifting of armature II, and the consequent retraction of the gravity lever 3.

A condenser 35, is shown connected at 36, 31, with contact bracket I9, and terminal 25, and 25 thus bridged across the magnet winding to suppress objectionable sparking in the mercur switch.

To render the device operable on alternating current, a lost motion connection is provided'be- 30 tween the gravity lever and tilting switch for effecting instantaneous firm closure of the circuit and immediate interruption. 'I'his lost m0- tion connection consists in the disclosure of a pin 33, projecting forwardly from an insulating disc 3,5

39, carried by the lever through a slot 40, in the dependentarm portion of switch bracket I'l.

In Fig. 3, the parts are shown as when the magnet has just lifted the armature to the top of its stroke. The movement thus imparted to the 40 lever is so sudden as to snap the mercury tube over beyond the angle of movement of the lever, the overthrow of the switch bracket leaving the pin 38, in an intermediate position clear of both ends of the slot 40. Consequently, the ratchet lever starts its downward active stroke acting only on the gear train and the pin 38, carried by the lever does not pick up the switch arm, by engagement with Vthe left hand end of slot 4.0, until the lever has performed most or a good part of its work and is approaching a position where it should be again returned to the top of its stroke.

Fig. 1 illustrates the relation of parts where the ratchet lever 8, under the weight of the solenoid core has lowered far enough to take up all lost motion at the left end of slot 40, and to rock the switch tube far enough for the mercury 34, to roll down the incline of the tube and press itself rmly across the ends of the contact pins 29, 3B. This closure of the circuit is instantaneous and so complete that the magnet is immediately fully energized. As a result, the armature is snapped upward and as there is lost motion for the pin 38, at rthe right hand end of slot 40, at such time, the ratchet lever 8 is free to move with the armature, clear of any impediment which the tilting vswitch might offer to such movement. Thus the lever can move in- A' stantly with the armature and as the travel of pin 38 takes up lost motion at the right hand end of the slot, a hammer-like blow will be imparted to the switch arm to snap the switch tubeY into the circuit open relation shownV in Fig. 3.

By such instant, full closing and immediate interruption of the circuit, the solenoid I3 will denitely and positively lift the Ycore with an instantaneous snap action and free of any chattering or other objectionable effects, commonly experience-d in A. C. operation.

The pivotal connection at Ill between the ratchet lever and solenoid core is preferably sufficiently loose to permit the core to have a substantially vertical motion despite the arcuate travel of the gravity lever and there may be sufcient freedom at this point to actually provide a definite amount of lost motion,.enabling the solenoid core to start free and then immediately pick up the ratchet lever.

The laminated structure of the core provides a convenient and elfective method of connecting the same with the ratchet lever. Thus as shown in the illustration, two of the relatively spaced laminations IIa,l IIb, may be extended down over opposite sides of lever 8, each engaged with the pivot'pin I4, projecting from opposite sides of the lever.

The construction is particularly simple and direct in action. The operation is quiet, but if desired, the entire movement may be cushioned and insulated so as to deaden any sound from the movement; In this particularillustration,

themovement is shown as connected by through` screws 4I, to a, panel 52, of wood or the like, and to. a supporting screen 43, and the latter is indicated as secured by screws 44, to the front of the case 45. This provides a non-resonant connection between the movement and the case, forms a resilient cushion mounting for the movement and keeps the movement quiet in operation.

To provide definite limits of movement'for the ratchet lever and attached solenoid core, the switch operating pin 38, of the lever is shown `extending freely through a stroke limiting arcuate slot 46, in the insulating base plate 20.

The pivot mounting screw I8 holds the Swinging switch arm I'I, in yielding face-to-face engagement with the terminal I9, assuring proper contact between these parts, but a spring washer, pigtail connection or equivalent may be provided at this point if considered desirable.

The magnet coil I3, preferably is of suiciently high resistance to operate safely on either 110 or 220 volts and since the construction disclosed is suited to either A. C. or D. C. operation the clock may be connected in on any usual service outlet. While the actuation of the ratchet lever by gravity alone is a desirable feature, the movement of the lever may be assisted or caused by a suitable spring or springs. Other changes may be made within the scope of the invention. The terms employed have been used in a descriptive rather than in a limiting sense, exceptpossibly as limitations may be imposed by state of the prior art.

What is claimed is:

1. In combination, a clock train including a ratchet, a lever pivoted on substantially the same center as said ratchet, a drive pawl for said ratchet carried by said lever, a substantially vertically operating solenoid core connected with and supported by said lever to. thereby operate as a weight for driving the clock train, a solenoid winding having a loose guide passage for said solenoid core, a swinging bracket pivoted on substantially the same center as the gravity lever, a lost motion connection between said lever and bracket, a mercury switch carried by said swinging bracket, circuit connections from said switch to said solenoid winding, said electromagnet winding being a high resistance A; C., D. C. winding and said solenoid core being laminated for A. C., D. C. operation. l v

2. In combination, a clock train including a ratchet, a lever pivoted on substantially thesame center as said ratchet, a drive pawl for said ratchet carried by said lever, a substantially vertically operating solenoid core connected with and supported by said lever tothereby operate as a weight for driving the clock train, a solenoid winding having a loose guide passage for said solenoid core, a swinging bracket pivoted on substantially the same center as the gravity lever, a lost motion connection between said lever and bracket, a mercury switch carried by said swinging bracket, circuit connections from said switch to-said solenoid winding and a spark suppressing condenser across the terminals of sai-dsolenoid winding.

EUGENE T. TURNEY.

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