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Patented Sept. 24, 1946
2,407,996
e STRQBOSCQPIC APPARATUS .EGR
`PHONOGRAI’HS
WilliamL. Nies, `WheatonJIl.
:ApplicationFebl-.uary 7, 1945, SerialNo. 576,630
`4 Claims.
,
(CIL 88-`--14l- »
2
.1,
This ‘invention relates `.to stroboscopic appa
ratusior use inconnection withregulating .the
speed „of rotation. of a Aphonograph record, land it
has for its object the provision of a new andim
proved arrangementcf `parts ywhereby the speedv >
i of .the , phonograph .may ,readily be .adjusted so »as
.to .cause .the reproduction `>to be `at -precisely .the ‘
same ._pitch asthat at which the recording` was
effected.`
.At times .a-.musicianfor amusic 4pupil desires `to
'playf asapart of‘anensemble` and uses for .this
purpose a. phonograph, record of the selection,
`and-_sometimes a specially . made record from
which' the part to be added has been omitted in
"the recording. In any‘such case, it is highly Aim
portant ‘that ‘thereproduction `be effected at the
illustrated inv ‘the accompanying drawing, in
which
i
Fig; 1_ is a diagrammatic `Avertical sectional
View through a phonograph >provided :with ¿the
improved apparatus.
Fig.- 2 is a »face View of> the structurel of‘Fig...1
as seen «from the right insaid figure; andl
îFig.. 3 -is .a bottom'facefviewfof a portion'of the
ring :by which fa :stroboscopicxscale is «attached Ato
the bottom face of the turntable of the ¿phono
graphpf Figa-1.
i
.
‘Referring ,now «"tofthev several `figures »ofiethe
drawing, :in which ycorresponding partsîare indi
catedlby @the = same »referenceicharactersg ll il -indi
ißcates'lthe turntable ora Aphonograph of :any ap,
prloved typey :drinenfbym¿vertical shaft 'i2 con
1Vsame speed as that‘at `wl‘lich‘the record was made,
`nesteiîlc?ïhrougih'la :suitable `'gear “box yI 4 with» the
which >is; ordinarily ‘at the` rate ' of ' approximately
shafftrofua’variable-:speed.motor Hi.`-` .As shown,
78.26 revolutions per-minute. The-exact `rate at
'the "turntable: I0 iaisxrotatably Vmounted :above a
which :recording is -effected ordinarily is that at 20 /large'opening flßì'in‘ :the‘top face cida-,housing 23
which a moving 92 step stroboscopic scale is made
which serves to shield the bottom face of the
to appear stationary when illuminated by a lamp
turntable effectively from the room lighting.
energized by 60 cycle alternating current. It is
On its bottom face, the turntable I0 is pro
accordingly the object of this invention to pro
vided with an annular plate or ring 22 ñxedly
vide an improved arrangement by which the re
connected thereto, such ring 22 being provided
production may be effected easily and conven
on its bottom face in concentric position thereon
iently at precisely this same speed.
with a 9-2 step stroboscopic scale 24, comprising
For effecting this result in the easiest and most
92 similar dots arranged in equally spaced rela
satisfactory manner, at a minimum cost for ap
tionship to each other about the ring. Below the
paratus and operation, a 92 step stroboscopic 30 ring 22 at one side, an electric lamp 26 is pro
scale has been employed so as to rotate in syn
vided, such lamp being preferably a small neon
chronism with the record and in such position
glow lamp of a type adapted to be energized by
as to be shielded from the room illumination, a
60 cycle alternating current for providing a small
special source of intermittently flashing light
amount of light sufñcient for illuminating the
being employed for illuminating the scale and in
scale on the ring 22. A mirror 28 is also provided
volving 120 separate flashes per second. By plac
in ‘position to reflect the image of a portion of the
ing the stroboscopic scale on the bottom face of
scale 24 outwardly through a window opening 30
the turntable by which the record is rotated and
in the face of the housing 20 below the ring.
protecting the scale from the room lighting, a
With a record in position on the turntable, the
comparatively small neon glow lamp can be ern
motor l5 is energized for driving the turntable
ployed to advantage energized by 60 cycle alter
and the speed of the motor is adjusted for 'bring
nating current, being adapted in the absence of
ing the drive of the turntable and the record to .
other lighting to provide sufñcient illumination
precisely the desired speed, such result when`
for enabling lthe operator readily and easily to
effected being shown by the fact that under such
observe the scale for determination as to whether
circumstances the stroboscopic `scale 24 appears
or not it appears to be moving. For- facilitating
to be stationary. By reason of the exclusion of
the observation of this scale, a mirror is pref
erably employed for directing the reflection of a
the room light from the face of the scale 24, a
fairly small amount of light from the lamp 26 is
adequate for enabling the operator easily to de
portion of the scale outwardly through a window
opening in the housing by which the scale is 50 termine when the adjustment of the motor is cor
shielded.
rect for holding the scale 24 apparently station
It is one of the objects of the invention to im
ary. The arrangement is such also that during
prove apparatus of this type in sundry details
the 4playing of the record the operator is able
hereinafter pointed out. The preferred means by
readily to observe any deviation'in the speed of
which the several objects have been attained is 5 01 rotation of the record, as shown b-y an apparent
2,407,996
4
said Window, and an electric lamp mounted in
said motor housing means in position to illumi
nate said scale Without illuminating said mirror
and adapted to be energized by alternating cur
rotation of the scale as reflected through the
window opening 30.
In case the lamps 26 Were to be energized by
an alternating current of a frequency other than
rent of a frequency to cause the scale markings
to appear to the eye to remain stationary when
the scale is rotated at a predetermined selected
the usual 60 cycles, the number of the markings
in the stroboscopic scale employed should be in
creased or cut down to correspond, as will be
speed.
readily understood by those skilled in the art.
3. A stroboscopic apparatus for use in connec
While >theforrn of apparatus as shownis pre
ferredfthe .invention’is not to be limited there 10> tion with regulating the »speed of .aïphonograpn
comprising in combination a turntable having a
to except so far as the claims may be so limited,
it being understood that changes might wellloe , ',stroboscopic scale on its bottom face, variable
speed mechanism for driving - said turntable,
made in the form and arrangement ofthe parts
_' housing means shielding ’said scale from the light
without departing from the invention.
of the room and having a window opening at one
What is claimed is:
' ’side ashortdistance below said turntable, a neon
` l.- A stroboscopic apparatus for use in connec
glow lamp adjacent to said Window opening in
tion with regulating the speed of a phonograph,
said housing means in position to illuminate said
comprising in combination a turntable having a
scale and adapted to be energized by alternating
stroboscopic scale on its bottom face, housing, 1
current of a frequency to cause the scale mark
20
means shielding said scale from the light of the
ings to appear to remain stationary when the
room, and an electric lamp mounted within said
scale is rotated at a predetermined selected speed,
housing in position to illuminate said- scale to the
Y and a mirror in position to reflect the light from
exclusion of other light, a window in said hous
said scale outwardly through said Window open
ing, means reñecting the image of said scale for
observation through said window, said lamp be» 25
4,. A stro‘boscopic apparatus for use in connec
ing.-
ing adapted to be energized by alternating cur
to appear to the eyeA to remain stationary vwhen
speed.
'
~
.
2. A stroboscopic apparatus for use inconnec
K
,
tion with regulating, the speed of' a phonograph,
rent of a frequency to cause the scale markings
~`the vscale is rotated at a predetermined selected
'
comprising in combination a turntable having a
92 step stroboscopic scale on itsbottorn face,
variable speed mechanism for driving said turn
430 tableyhousing means‘shielding said scale from
tion' with regulating the speed of a phonograph,
v‘comprising’ in combination a motor and a turn
“tablehaving ‘a stroboscopic scale on itsy bottom
the light of theroom> and havinga windowvopen
ingV at oneV side a short distance below said turn
table„a neon glow lamp adjacent to said window
opening in said housing means in position to il
face, motorv housing means shielding said scale` 35,
Y luminate said scale and adapted to be energized
‘from the light of the room,'said'motor housing
by60 cycle alternating current,l and amirror in
"meanshaving an opening adjacent the bottom of
said turntable and having a windowopening, a
mirror mounted‘a short distance below said turn- ï'
table to reilect the image of said scale through
position to reflect the Vlight fromr‘said scale
outwardly through said Window opening.
WILLIANI L. NIES. '
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