US2843812A - Flasher mechanism - Google Patents

Description

July 15, 1958 c. L. CRADDOCK FLASHER MECHANISM 2 sheets sheet 1 Filed 001;. '7, 1954 CAW 5 4. 684290066 IN VEN TOR.

annex/5V July 15, 1958 c. L. CRADDOCK FLASHER MECHANISM 2 Sheets-Sheet 2 Filed Oct. 7. 1954 142.455 L. ce/woocz JNVENTOR.

FLASHER MECHANISM Charles L. Craddoclr, North Hollywood, Calif., assignor of one-half to J. E. Metcalf, Los Angeles, Calif.

Application October 7, 1954, Serial No. 460,809

3 Claims. (Cl. 318-434) This invention relates to mechanisms for causing an automatic recurrent flashing of an electric lamp and has particular utility in operating self contained neon tube flasher units energized by a low voltage dry battery.

A flasher unit of the latter type includes a transformer the primary of which functions also as an electromagnet, when energized, to attract an armature mounted on the free end of a spring reed and carrying a contact, which is thus caused to move another contact carried by a lightly spring biased oscillator to swing the latter through a substantial are against its spring and away from the reed contact. These contacts are terminals in a gap in the transformer primary and battery circuit and are initially brought into contact by movement of the oscillator imparted by its spring.

The initiating of a cycle in this manner energizes the transformer causing the armature to impart a rapid rotary impulse to the oscillator which breaks the engagement between the contacts. This deenergizes the transformer permitting the spring reed to return the armature to its normal spacing from the transformer. As the oscillator spring gradually overcomes the momentum of the oscillator the increased tension of that spring reverses the rotation of the oscillator and returns the latter to contact engaging position, thereby initiating another cycle. The making and breaking of the primary transformer circuit induces transient voltage impulses in the secondary which is connected with the neon tube, thereby producing correspondingly timed intermittent flashes in this.

It is the general object of the present invention to provide an improved automatic flasher operating mechanism for use in such a flasher unit which realizes one or more of the following specific objects:

(1) To provide a better mechanism at a lower cost.

(2) To decrease the cost by providing an integrated assembly unit including a sub-frame embodying therewith the contact oscillator, the actuating spring, and the contact reed, ready to mount on the transformer and connect.

(3) To decrease the cost by substituting for the expensive ball bearing, heretofore used to mount the oscillator, a relatively cheap smooth journal bearing made of nylon, Teflon, Kel F or other similar polymerized ester, the bearing thus substituted having high antifriction characteristics, requiring no lubrication, and having equal lasting qualities to the bearing replaced.

(4) To enhance the power applied to the reed in each power cycle by providing on the reed at the transformer gap a flat solenoid which is connected with the transformer primary and energized concurrently therewith.

(5) To extend the life of the dry battery energizing the mechanism by cutting the dwell time, getting cleaner contact operation, suppresing arcing, and reducing the transient A. C. voltage increment by reason of the high forward E and I characteristics of a diffused junction germanium rectifier placed in series with the battery and the contact points.

(6) To extend the life of said dry battery by dampenatent 2 ing the vibration of the armature reed between energizing contacts therewith, thereby rendering more uniform the successive operating cycles of the mechanism.

The manner of accomplishing the foregoing objects as well as further objects and advantages will be made manifest in the following description taken in connection with the accompanying drawings in which:

Fig. 1 is a front elevational view of a preferred embodiment of the mechanism of the invention with the housing thereof shown in section.

Fig. 2 is a right side elevational view of Fig. 1 with the housing also in section.

Fig. 3 is a left side elevational view of Fig. 1 with the housing omitted.

Fig. 4 is a back elevational view of Fig. 3.

Fig. 5 is an enlarged detailed sectional view of the improved oscillator bearing of the invention, taken on line 5-5 of Fig. 3.

Fig. 6 is a plan view of the invention.

Fig. 7 is a simplified wiring diagram of the circuits of the invention.

Fig. 8 is adiagrammatic illustration of the armature solenoid of the invention.

Referring specifically to the drawings, the invention is there shown as embodied in a flasher mechanism 16 having a base it which forms the cover for a cup shaped housing 12 which, with the base 11, completely encloses thev mechanism 10. The housing is omitted from most of the views to facilitate illustrating the working parts of the mechanism.

The base 11 comprises a fiat plate having a suitable aperture in which a four terminal electric outlet socket 13 is mounted and the purpose of which will be described later. The base 11 also has apertures for. receiving threaded studs 15, welded on the housing 2, to assemble the base and housing.

Spot welded on the base it is an angle member 16 the Vertical flange of which forms two legs 17 which are apertured near their upper ends to receive bolts 18.

Secured to the legs 17 by bolts 18 is the laminated core 19 of a transformer 2% the primary winding 25 of which also functions in the mechanism Ill as an electromagnet.

The core 19 extends centrall through the primary and I secondary windings 25 and 26 and is joined above and below the windings except for an air gap 27 at the upper left corner of the core (Fig. 1).

Diamagnetic pads 28 space the core 1? from support legs 17.

Also secured to the core 19 by bolts 18 and spaced from said core by diamagnetic pads 29 is a unitary subassembly frame 30. This frame preferably comprises a sheet metal stamping, the main body of which lies in a vertical plane parallel with the core 19 and spaced therefrom by the thickness of pads 29, and with an inverted U-shape so as to extend down about windings 2526 to receive bolts 18 (Fig. 4).

Bent horizontally from an upper edge portion of frame 30 to closely overlie core 19 at the opposite side portion thereof from core gap 27 is a spring reed mounting lug 31. Clamped to the bottom surface of this lug by a bolt 32 with a large square nut 33 is a laminated spring reed 34,. The reed 34 has a soft iron armature 35 spotwelded to the under surface thereof and overlying the area surrounding the core gap 27.

Secured, as by riveting, to the free end portion of reed 34 is an electric contact 40 which faces downwardly. To dampen vibration in reed 34, this is of laminated construction and includes a layer of thin plastic material 41 which overlies and is coextensive with the upwardly exposed portion of reed 34, and is secured thereto by a suitable tacky pressure adhesive.

Adjacent the lug 31 and from the same edge of frame 3 30, a lug 42 extends straight upward and is apertured to receive a plastic grommet 43 for a purpose to be explained later.

Bent rearwardly from the left vertical edge of frame 30 is an oscillator mounting lug 44 having a bearing hole 45. Extending through this hole is an externally threaded sleeve 46 having a bore 47 and an external hexagonal flange 48 at one end. A nut 49 and lock washer 50 secures the sleeve 46 in hole 45 with the bore 47 normal to the vertical plane of lug 44.

Pressed into the bore 47 is a tubular cylindrical bearing 55 having a flange 56 at one end which is pressed against the adjacent end of sleeve 46 with the opposite end of bearing 55 extending from bore 47.

The bearing 55 is made of nylon, Teflon, Kel F or the like; and provides a smooth bore journal for metallic shaft 57 to one end of which a metallic oscillator 58 is fixed. This oscillator may have any .of a variety of shapes but is preferably shaped as shown in the drawings with one end narrowed and twisted to provide a mount for an electric contact 59.

Fixed on the opposite end of shaft 57 is a collar 60 having a hair spring 61 mounted thereon. This collar also limits end play of shaft 57 to locate oscillator 58 in a plane causing oscillator contact 59 to squarely engage spring reed contact 40 as shown in Figs. 1 and 3 when the oscillator is rotated in counter-clockwise direction.

The outer end of hair spring 61 is embedded in a lump of solder 62 deposited in the opening of grommet 43, so as to maintain oscillator 58 spring biased in a counterclockwise direction with oscillator contact 59 engaging reed contact 40 as shown in Figs. 1 and 3.

The outlet socket 13 mounted on the base plate 11 has four terminals 63, 64, 65 and 66. An outlet plug (not shown) plugs into the socket 13 so as to electrically connect said terminals respectively with ungrounded terminal 70and grounded terminal 71 (of a neon tube 72) and with negative terminal 73 and positive terminal 74 of a 6-volt dry battery 75.

A lump of solder 76 is deposited on the lug 31 to adhere thereto.

In the mechanism 10, terminal 63 is connected by insulated wire 83 with the outer end of secondary winding 26; terminal 64 is connected by a wire 84 to lump of solder 76; terminal 65 is connected by a diffused junction germanium rectifier 85 having lead wires 86 and 87 with solder lump 62; while terminal 66 is connected by a wire 88 with the outer end of primary winding 25.

The inner ends of both primary and secondary windings 25 and 26 are connected by a wire 89 with solder lump 76. Shunted across solder lump- s 62 and 76 is a condenser 90 having leads 91 and 92.

Outside the mechanism 10, a wire 95 leading from negative battery terminal 73 to the plug (not shown) connecting with terminal 65 of socket 13, has a snap.

switch 96 by which the mechanism is manually turned on or shut off.

In practice, the mechanism 10 is embodied with a flasher unit (not shown) said unit containing the battery 75, neon lamp 72, and switch 96.

When switch 96 of that unit is closed, thus turning the unit on, contacts 40 and 59 are already in engagement thereby causing energizing of the transformer and the immediate initiation of a flasher cycle by a sudden thrust of the contact against contact 59. Being applied to oscillator 58 at its maximum radius, this thrust imparts a rapid rotary movement to oscillator 58 against the constant reverse bias of hair spring 61.

Disengagement with reed contact 40 by oscillator 'contact 59 breaks the circuit of transformer primary 25, thereby creating a transient voltage impulse in the secondary winding 26 which produces a flash of light in neon tube 72. This also releases reed 34 and armature 35 from magnetic attraction by the transformer 20 allowing the '4' reed to return to its normal spaced relation with transformer core 19.

The rotary movement imparted to oscillator 58 is of course decelerated by the hair spring 61 so that after rotating through an arc of from to 90, the oscillator reverses direction and is swung back by hair spring 61 to engage contact 59 with contact 40. This starts another cycle which in turn starts another so that as long as switch 96 remains closed, neon lamp 72 is illuminated by a continuous series of spaced flashes.

The diffused junction germanium rectifier 85 by reason of its high forward E and I characteristics reduces the transient of A. C. voltage increment, gives cleaner contact operation, tends to suppress arcing and gives a shorter dwell time. The net result is thus to extend the battery life.

A modified form of armature 97 is shown in Fig. 8 which may be substituted for the plain soft iron armature 35 described. To accommodate the greater depth of armature 97, the spring reed 34, in such a case, is preferably applied to the upper face of lug 42 instead of to the lower face, as shown in Figs. 1, 2, 3 and 6.

The armature 97 comprises a solenoid including a spool 98 of soft iron and a winding 99 thereon the axis of which lies in the vertical plane of transformer core gap.27. The winding 99 is connected in series with transformer primary winding 25 so as to be energized each time contact 59 engages contact 40.

When using armature 97, the result of such engagement is to develop a substantially greater downward thrust of contact 40 against contact 59, as the magnetic field of the transformer 20 is enhanced by that of the solenoid comprising armature 97. This increase in thrust increases the angle through which oscillator 58 is caused to rotate before the momentum. imparted thereto by said thrust is overcome by hair spring 61 and the energy thus stored in the latter expended in returning the oscillator to where it is halted by engagement of its contact 59 with reed contact 40.

The annature 97 may either be used to produce a greater movement of the oscillator to increase the period between successive flashes of the neon tube 72 or it may be used to decrease the size, weight and cost of transformer 20 while still producing the same total thrust in the power phase of each operating cycle.

The claims are:

1. In a flasher mechanism the combination of: a base; an electromagnet mounted on said base, said electromagnet including a core and a winding applied to said core; a unitary sub-assembly frame comprising a U-shaped sheet metal stamping the main body of which lies parallel with and close to the core of said electromagnet and straddles the winding thereof; a first lug extending at a right angle from one edge of said stamping to overlie said core; a second lug extending at a right angle from a diflerent edge of said stamping and in the opposite direction from said stamping from the direction said first lug extends therefrom, said second lug being disposed in a plane lying at right angles to the plane of said first lug; a spring reed having a base end portion and a free end portion, said base end portion of said reed being mounted on said first lug; a contact mounted on the free end portion of said reed; an armature mounted on said reed between said end portions thereof; a bearing provided on said second lug on an axis at right angles to said lug; an oscillator pivotally mounted in said bearing; a hair spring one end of which is connected to said oscillator and the other end of which is connected to said frame; a contact provided eccentrically on said oscillator so as to travel on a path when said oscillator rotates which brings said oscillator contact into engagement with said reed contact, said hair spring normally biasing said oscillator to bring said contacts into engagement; means securing said sub-assembly frame to said core to properly relate said armature to said core whereby the energizing of said electromagnet delivers an impulse from said reed contact to said oscillator contact causing an oscillation of said oscillator which temporarily separates said contacts; and conductor means which, with said contacts, provides an electric circuit for energizing said electromagnet.

2. In a flasher mechanism the combination of: an electromagnet the core of which has an air gap; an armarure comprising a fiat solenoid; a spring reed fixed at one end and having said armature mounted on the other end close to and bisected by the plane of said gap and yieldable toward and away from said core; a contact on the magnet side of the free end of said spring reed; an oscillator having a contact; means rotatably mounting said oscillator whereby rotation thereof in a given direction brings the oscillator contact into engagement with the spring reed contact with the latter spaced from said core; a hair spring rotatably biasing said oscillator to normally produce such an engagement of said contacts; and conductor means providing 'an electric circuit for energizing said electromagnet, said circuit including said contacts and the winding of said armature solenoid.

3. In a flasher mechanism the combination of: an electromagnet; an armature; spring means for mounting said armature in closely spaced relation with the core of said magnet and yieldable rapidly towards said core when attracted by said magnet; a contact carried by said means to move said armature as aforesaid; an oscillator having a contact; means rotatably mounting said oscillator whereby rotation thereof in a given direction brings the oscillator contact into engagement with the armature contact; a hair spring rotatably biasing said oscillator to normally produce such an engagement of said contacts; a battery; a diffused junction germanium rectifier; and conductor means providing an electric circuit extending from the positive pole of said battery through said electromagnet, then through said points, and then back through said rectifier to said battery.

References Cited in the file of this patent UNITED STATES PATENTS 858,928 Varley July 2, 1907 2,122,847 Shattuck July 5, 1938 2,129,882 Shattuck Sept. 13, 1938 2,219,923 Henninger Oct. 29, 1940 2,240,781 Ives May 6, 1941 2,459,598 Stott Jan. 18, 1949 2,645,729 Frank July 14, 1953 2,666,677 Miller Jan. 19, 1954 FOREIGN PATENTS 710,530 Great Britain June 16, 1954

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