SIGN FLASHERS
The devices used for giving the flashing and changeable effects to
electric lights in any form are called "flashers." The mechanism may be
constructed to flash a sign by spelling the words out, one letter at a
time, flashing border lights around a window, changing colors in glass
signs, or in fact in any way to attract the eye.
There are two advantages in favor of using a flasher: 1, it causes the
passerby to look at the sign, and 2, reduces the cost of electricity,
because the lamps are switched off periodically.
There are numerous kinds of flasher, and they may be classified,
according to construction of the switch contacts, as:
1. Carbon type;
2. Brush type;
3. Knife type.
Again, with respect to operation or the electrical effects, they may be
classified as
1. Simple on and off flashers;
2. High speed flashers;
3. Lightning flashers;
4. Script breakers;
5. Chaser flashers;
6. Thermo flashers;
7. Carriage calls;
8. Talking signs;
9. Electric clocks.
[Illustration: FIG. 1,011—Dull's carbon type flasher. This is a
main line flasher; that is, it is set into the main wires instead of
carrying down each circuit. The circuits are opened and closed on
carbon contacts, reinforced with standard knife switches. The blades
are opened and the current broken by gravity alone. Each switch can be
made to hold the lights for any period from 18% to 81% of a revolution
of the shaft. They can throw on the circuits progressively or all on
and all off together. Again, the circuits may be closed progressively,
remain on a few seconds, and then be opened progressively. No circuit
or circuits can be closed more than once per revolution.]
=Carbon Flashers.=—In this type of flasher, carbon breaks are
provided, that is, the arc which is formed when the circuit is broken,
falls on carbon, while metal switches are provided to carry the load.
Thus the carbon gets the arc which prevents the switches burning, while
the switches carry the load to prevent the carbons becoming heated and
disintegrated. The carbons must be adjusted occasionally according to
the load they are carrying. Carbon machines are made either double,
triple, or series break.
[Illustration: FIGS. 1,012 to 1,014.—Wiring diagrams for Dull's carbon
flashers. Fig. 1,012, usual method of wiring. The load is balanced by
running the neutral wire around the machine, to the cut outs, breaking
the outside "legs" only of a 220-110 volt system. While this method
of wiring is entirely feasible, it is no harder on the contacts, and
permits the use of a cheaper machine, but it is technically a violation
of the underwriters' rules, which say that all circuits of more than
660 watts must be broken double pole. If the load be balanced there
would be double pole break at 220 volts, and the lamps would be in
series, but if the load be not exactly balanced, there would be single
breaking to the extent of the amperes over the average balance.
In other words, it is a double break and it is not according to
circumstances, and the use of this machine wired as above is a matter
that should be taken up with the local inspector before installing.
Fig. 1,013, diagram for connecting a straight two wire carbon flasher
on a two wire system. Fig. 1,014, diagram for connecting a straight
three wire carbon flasher on a three wire system and breaking the
neutral.]
[Illustration: FIG. 1,015.—Reynolds' brush type flasher. The brush
type, as its name indicates, is of brush construction and is limited to
5 amperes capacity on each switch. The cams constituting a drum are of
heavy construction while the brushes are of fine copper several leaves
thick. It is most commonly used for spelling signs, that is, for letter
by letter flashing.]
[Illustration: FIG. 1,016.—Reynolds' knife type of flasher with metal
contacts. The construction is cheaper than the carbon type. It is
mounted on a slate base, and is heavily built throughout. The switches
are designed for 15 amperes capacity double break.]
=Brush Flashers.=—These machines are provided with brush contacts.
These bear on cams constituting a drum, and they are usually made
of several strips of copper. Brush flashers are generally used for
spelling out signs one letter at a time, or work of a similar nature.
[Illustration: FIG. 1,017—Sign flasher transmission gearing. The view
shows an oil tight gear case with cover plate removed. The gears are
equipped with ball bearings and run in graphite grease. By means of the
worm gear the large speed reduction necessary between the flasher shaft
and motor is obtained without a multiplicity of gear wheels.]
=Knife Flashers.=—This type of construction is cheaper than the carbon
type. The switches are of the knife type with metal contacts. One
manufacturer states that it is not advisable to build knife flashers
for more than 15 amperes per double pole switch, as they cannot be
depended upon to break a greater load for any length of time.
=Simple On and Off Flashers.=—These are used for flashing whole signs
or heavy loads on and off. A flasher of this type consists essentially
of a revolving double pole switch with reducing gear and connection to
a small motor for operating same.
[Illustration: FIG. 1,018.—Simple on and off double pole flasher for
"all on" or "all off" sign flashing. The machine is furnished with any
number of switches ranging from 5 amperes up.]
The machine may have only one switch or any number of switches. The
connection to motor may be by belt or chain, or the motor may be
directly connected to the worm gear.
* * * * *
=Flash System of Gas Lighting=—This system for simultaneously lighting
a large number of gas burners, is used in large halls, churches,
theatres, etc. Two sparking points, each insulated one from the other
and from the burner, are arranged at each burner, so that a spark
between the points passes through the jet of gas and ignites it. A
number of sparking points and the secondary of an induction coil
are connected in series. When the circuit through the primary of
the induction coil is closed, sufficient pressure is induced in the
secondary to cause sparks to jump across every jet in the series. Since
the voltage is high, the wires must be installed with great precaution.
The wire should be enclosed in glass tubing wherever it comes within
less than 1¼ in. from the gas piping, except where purposely
grounded.
=High Speed Flashers.=—Machines of this type are used for giving what
is generally known as _high speed effects_, such as fountains, water,
steam, smoke and fire effects, whirling borders, revolving wheels and
work of a similar nature.
[Illustration: FIG. 1,019.—Dull's high speed flasher. It is mounted on
a slate base 12 inches wide, the length being governed by the size of
the machine. Motion is given to the rotary switches through worm and
belt gearing. Iron cams are used, the current being taken therefrom by
six-leaf brushes, provided with stiffeners. The wiring for the machine
is simple; 4 c.p. lamps can be run on one wire. A border or ornament
containing 160 lamps requires 12 wires between the sign and flasher.
The flasher is made in 4 switch sizes only, viz.: No. 4, 8, 12, 16,
etc. This is due to the fact that there are three parts of light to one
of darkness.]
=Lightning Flashers.=—These machines are for giving the appearance
of a streak of lightning going across a display. There is very little
expense attached to their operation, because not more than two-thirds
of the lamps are turned on at one time, and this number for only about
one-sixth of the time, as compared with the sign burning steadily.
Lightning strokes can be utilized in various ways, either alone or with
other advertising pieces. Alone they can be placed along a cornice,
across the front of a building, up and down the corners leading to a
doorway, etc. They can be used in the center of a sign with letters
above and below. In this case, it is best to alternate the stroke with
the letters, that is, flash the wording on and then off. As soon as it
goes out, the stroke flies across in the darkness, then the wording
comes up again, say six times a minute.
[Illustration: FIG. 1,020—Wiring diagram for flags. These may be
wired for high speed flashers by gradually increasing the lamp centers
between the vertical rows from the flag staff to the end.]
[Illustration: FIG. 1,021.—Diagram showing method of wiring for high
speed effects on single lines. This wiring diagram would be carried out
the same in the case of a travelling border, whether it be straight or
otherwise. In the case of a fountain, begin numbering each stream at
the bottom and carry out the same scheme to the end of that stream.
When several streams are parallel, all the lamps may be connected in
a row the same as though they were an individual lamp. Care should be
taken not to get more than twenty No. 1 lamps on a circuit. Among the
effects that may be obtained are a revolving wheel, a column of flame,
and a straight travelling border with part of the No. 1 lamps from
each effect to the same No. 1 wire, carry it back to any No. 1 switch
on the machine, and the effect will come out right. For instance, in a
flame effect with sixteen No. 1 lamps, four No. 1 lamps could be taken
in the straight border, and put on the same wire, and the effect would
come out right. The spacings for high speed effects vary, according
to the size of the sign. Travelling borders around an ordinary sign 3
x 10 feet should have their lamps spaced about six inches apart. In
a fountain fifteen feet high, the lamps should be spaced about nine
inches apart.]
[Illustration: FIG. 1.022.—Method of wiring for a torch. This wiring
diagram gives the correct method of wiring smoke, flames, steam, and
water effects. It may be the flame in the top of a torch as here shown,
liquid pouring out of a bottle, smoke rising from a cigar, or dust
behind an automobile wheel. The only difference being in the direction
each goes and the outline of the bank of lamps. Wire the lamps in
unequal lines across; avoid any straight lines because it gives a
mechanical effect which is not natural. If the effect be to rise, mark
the lower row No. 1, the next row above No. 2, etc. Pick up all the
No. 1 rows until there are twenty lamps, and attach them to No. 1 wire
which will go back to any No. 1 switch on the machine. Do the same with
the other numbers. Do not overload line as this will decrease the life
of the contacts.]
[Illustration: FIGS. 1,023 and 1,024.—Wiring diagrams for high speeds.
Where a high speed flasher is used on a spoked wheel containing more
lamps in the rim than the number of spokes, the extra rim lamps must
be connected to the spoke circuits, so that the number of rim circuits
will equal the number of spokes; otherwise, the rim will appear to
travel slower than the spokes.]
In the case of a sign already in use, on the front of a building or
over the sidewalk, a stroke can be placed leading to the sign from any
point above. The flash goes down and when it hits the sign the latter
lights up, holds a few seconds, goes out, and repeats about four times
a minute.
[Illustration: FIG. 1,025—Dull's lightning type flasher for giving the
appearance of a streak of lightning going across a display.]
Lightning flashes are not usually constructed for heavy loads, the one
shown in fig. 1,025 being designed for two amperes.
=Script Breakers.=—Flashers of this type are used for breaking large
script signs, one socket at a time; that is, each lamp is lighted one
after another until all are on. After a few seconds they all go out
simultaneously and repeat. This gives the appearance of an invisible
hand, writing the name in the darkness, and is very effective. The
result can be accomplished only with script, and to get the proper
effect the smallest letter in a sign should be not less than two feet
high; the larger the letter, the better the effect.
[Illustration: FIG. 1,026.—Betts' script breaker (brush type). This
flasher is especially designed for spelling out signs one letter at a
time, or work of a similar nature, The brushes for the revolving cam
contacts are of copper, several leaves thick and provided with special
brush holder to prevent loose contact and abnormal burning.]
Script breakers are also used for fancy border signs of other kinds,
and in order to produce these results, it is necessary that the return
wire of every lamp go back to the flashers independently, which means a
wire for each lamp.
=Chaser Flashers.=—This class of flasher is designed to operate signs
whose lamps are arranged to give the effect of snakes chasing each
other around the border. This peculiar effect is produced by having a
separate wire and a separate switch on the flasher for each two lamps
in the border, and the mechanism so arranged that when the tenth lamp
is lighted (assuming the snake to be ten lamps long) the first lamp
goes out; when the eleventh is lighted, the second goes out, etc.,
progressing in this way around the entire border.
[Illustration: FIG. 1,027.—Reynolds chaser type of flasher, as used on
electric signs whose lamps are arranged to give the effect of snakes
chasing each other around the border of a sign.]
In operation, the lamps are turned on and off so rapidly that it
produces the effect of snakes.
It is not advisable to build these signs small nor cheaply, as
in order to produce the desired effect, the curved path taken
by the snake should cover at least 10 inches width, which
would mean a total of 20 inches lateral space for the snake in
addition to the electric letters in the center. In order to get
the proper effect, the sign should be at least ten feet long.
=Ques. Why are chaser signs expensive?=
Ans. It is on account of the care required in their construction, large
amount of wiring necessary and large flasher required.
A sign four by ten feet outside dimensions, would require in
the neighborhood of 150 lamps in the border alone on each side.
This would require a flasher with 75 switches and about 82
wires to run between the sign and flasher.
[Illustration: FIG. 1,028.—Chaser wiring diagram for two snakes.
Draw a line diagonally through the sign (as shown in dotted line) so
that one-half the total lamps will be on either side. Begin to number
from one consecutively to the line. Over the line commence again at 1
and number as before. For three snakes, divide total lamps into three
parts and number as before. In each case, connect all lamps of the same
number to the same wire whether the sign be single or double face. The
wire containing all the No. 1 lamps goes to the No. 1 switch on the
flasher, and the remaining sets are connected similarly.]
=Ques. How are chaser signs worked?=
Ans. There are several ways of operating these signs. The border is
generally working continuously, while the center can be flashed or not,
as may be desired. Flashing the wording reduces the current expense,
which offsets in a measure the extra cost of the sign.
The border, although working continuously consumes very little
current.
=Ques. What is the relative cost of a one snake sign as compared with a
two snake sign?=
Ans. One snake running around the border would cost twice as much for
flasher and wiring as a two snake flasher.
Three snakes would cost about 25 per cent. less for flasher and
wiring than for two snakes. The smaller the number of snakes
travelling around the border at one time, the greater the
expense of wiring and flasher.
[Illustration: FIG. 1,029.—Thermo flasher. It consists of two metal
strips, one of brass and the other of iron, about 5"x ½" x 1/32" each.
The brass strip is provided with a winding of fine wire over asbestos
and the two strips are connected to the base as shown. One terminal of
the winding is connected to J, and the other end to M. At the end of
the strips is a small contact screw N with locknut O, and below is a
contact plate L, fastened to the base and terminal post R. The flasher
is connected at P and R in series with the lamp it is to flash, and
N adjusted so that it clears the plate about 1/32 inch when there is
no current flowing in the winding. When the switch is turned on there
will be a current through the lamp and winding in series. The brass
strip will be heated more than the iron and it will expand more, thus
forcing the point of the screw N down upon the brass plate, which will
result in the winding about the brass strip being shorted and the full
voltage will be impressed upon the lamp, and it will burn at normal
candle power. When the coil is shorted there will of course be no
current in its winding and the brass strip will cool down, the screw
N will finally be drawn away from contact with the brass plate, and
the winding again connected in series with the lamp. The lamp will
apparently go out when the winding is in series with it, as the total
resistance of the lamp and winding combined will not permit sufficient
current to pass through the lamp to make its filament glow. The time
the lamp is on and off may be varied to a certain extent by adjusting
the screw N.]
=Ques. How many snakes should there be for best effect?=
Ans. Two is considered best. Three may be used on some signs, but more
than four would, in most cases, so crowd them as to spoil the effect
entirely.
=Thermo Flashers.=—These flashers work on the thermo or heat expansion
principle, that is, the movement of the contact points of the flasher
necessary to open and close the circuit is obtained automatically by
the alternate heating and cooling of the metal of the flasher, which
causes it to expand and contract.
[Illustration: FIG. 1,030.—Thermal flasher. This simple flasher
consists of a brass strip fixed at each end to a porcelain base and
slightly arched upwards. The amount of this arching, however, is much
less than is shown in the figure. The center of the strip carries a
platinum contact on its upper surface, and opposite this is a platinum
tipped contact screw which is carried in a brass angle piece fixed
to the base. One terminal is fitted on one end of the strip, and the
other is connected, through the angle piece, with the contact screw.
The strip is wound from end to end with an insulated resistance wire,
one end of this being soldered to the strip, and the other connected
to the right hand terminal. When this device is switched into circuit
with the lamps, the current first flows through the resistance, which
cuts it down so much that the lamps are not visibly affected. The heat
generated in the resistance causes the strip to curve still more, till
at length contact is made, the resistance short circuited, and the
lamps lighted.]
[Illustration: FIG. 1,031.—General Electric thermal flasher. It
consists of a small brass cylinder fixed at its left hand end to one
of the terminal blocks. The junction between the two is hidden by a
portion of the cover, which is shown broken away. The right hand end
of the cylinder carries a cross piece bearing a platinum contact; and
opposite this is the platinum tip of a contact screw carried in the
other terminal block. The cylinder is wound with a heating coil of
manganin resistance wire, one end being soldered to the cylinder and
the other to the right hand terminal. When the current is switched
on, the coil and the cylinder warm up and the cylinder elongates
sufficiently to make contact and light the lamps. The coil being then
short circuited, it and the cylinder cool down, and contact is broken,
whereupon the coil is put in circuit once more, and warms up again.
In some sizes of this flasher, the contact gap is shunted by a small
condenser fitted beneath the base. This helps to eliminate the sparking
at the contacts.]
=Carriage Calls.=—These are used to avoid the confusion and noise at
the theatre, club house or department store when vehicles are called by
a megaphone.
[Illustration: FIG. 1,032.—Monogram or unit for carriage call or
talking sign. It consists of a collection of metal compartments
each arranged to receive an incandescent lamp. The purpose of these
compartments is to confine the light to a certain space, thus forming a
clearly defined number or letter which can be read from a distance.]
[Illustration: FIG. 1,033 and 1,034.—Wiring diagrams showing proper
methods of wiring for illuminating a painted sign. The lamps are placed
about one foot apart in an overhead inverted trough. They should
project out in front of the sign one-half its width, but no sign should
be more than eight feet wide, as ordinary 16 c.p. lamps will not carry
any farther. Black and white paint only should be used. The lamps may
be flashed on and off as a whole, saving one-half the current, or they
can be flashed in different colors as desired. For flashing in colors,
only red and amber should be used. No other colors, such as green,
blue, etc., will give sufficient light to produce a good effect.]
The call itself consists of two or more sheet steel boxes, one of which
is shown in fig. 1,032, with incandescent lamps arranged in metal
compartments in such order that any number may be produced by lighting
the proper lamps.
[Illustration: FIG. 1,035.—Operating keyboard for three number
National carriage call. The keyboard here shown is designed to control
a three number call, there being a row of keys for each monogram or
unit of the call. Its dimensions are 4 inches deep, 18 inches wide and
19 inches long. The base is of slate. There are fourteen wires for each
monogram and one return wire, coming out of the call.]
The flashing of the number is controlled by a keyboard or switch which
may be placed in any convenient location. When the switch and call
are connected together, any numeral may be flashed by pressing the
corresponding key. The numeral automatically remains lighted until the
releasing button is pressed.
[Illustration: FIG. 1,036.—Clock monogram or electric sign clock,
operated by the mechanism shown in fig, 1,037.]
[Illustration: FIG. 1,037.—Betts' clock mechanism for operating
electric monogram time flasher. The secondary mechanism consists of
a three cylinder flasher and is controlled by a master clock which
transmits an electric impulse through a relay switch one each minute.
This flashes the time in figures on the monogram, viz.: 11.45, 11.46,
11.47, 11.48, etc. The first monogram to the left consists simply of a
vertical row of lights representing the figure one. Each of the other
monograms of metal compartments so arranged that any figure may be
produced by lighting the proper combination of lamps.]
=Talking Signs.=—This type of electric sign automatically flashes out
in brilliant letters, different phrases or announcements. These are
flashed out repeatedly and continuously during the operation of the
sign and the changes follow each other without intermission of darkness.
[Illustration: FIG. 1,038.—Two way thermal flasher. The moving portion
consists of a rocking arm _A_ pivoted at _p_, and carrying two sealed
bulbs, _B_, _B'_, whose bottoms are united by the tube _T_. Inside
there is sufficient mercury _M_ to fill _T_ and the bottoms of the
bulbs, the remainder containing air. At each end of _A_ is fixed an
insulating block _I_, _I'_, carrying two contact prongs _P_ and _P'_,
which are connected together at the top through heater wires _H_, _H'_
sealed in the bulbs _B_ and _B'_ respectively. _MC_, _MC'_ are pairs
of mercury cups, the further one of each pair whose stud is marked +,
being connected together to the positive pole of the circuit, while
the front ones are joined up to the respective groups of lamps. The
action is as follows: If the apparatus be in the position illustrated,
when the circuit is closed at the time _P_ is down, lamp group No. 1
will light up, the current passing through _H_ on its way. The air
in _B_ consequently expands, and gradually forces the mercury down
in _B_, along _T_, and up in _B'_. The arm _A_ will gradually become
horizontal, and will then overbalance, _P_ being withdrawn from _MC_,
and _P'_ dipped into _MC'_. Lamp group No. 1 will consequently be
extinguished and lamp group No. 2 lighted; _H_ will cool down, and _H'_
will warm up. Thus, in due course, _A_ will be tilted the other way
again.]
The talking sign consists of any desired number of monograms or units,
in each of which any letter or figure can be formed by lighting
certain combinations of incandescent lamps. A unit is shown in fig.
1,032. The lamps are controlled by a simple mechanical arrangement
operated by a small motor. Any reading matter can be flashed by
properly setting the mechanism.
The flashing of the letters or numerals in the monogram is controlled
by commutators, one commutator being required for each monogram, except
for a double faced sign where the corresponding monogram on each side
is controlled by the same commutator.