close

Вход

Забыли?

вход по аккаунту

?

Патент USA US2119218

код для вставки
‘if 2,119,218
'Patented'May 31, 1938
‘UNITED’ STATES‘- PATENT‘ "or-‘rice A *
Stuart .1. Rodger, New main. Y.,-assignor to‘ .
Jacob Strauss and Isidore H. Goldman, both- of I
New'York, N. Y.
Application December 24, 1937, Serial No.‘181‘,495
4 Claims.
(01.
74-190)
~
-
a
‘
.
phonograph turntable drive~capab1e of operating
. gether with vinstantaneous changeability from
either speed to the‘ other. '
‘
Another object of this invention is to devise
such a phonograph turntable drive which drives
In the art of sound recording and reproducing,
two separate rims as disclosed in my copending
This inventionrelates-to phonographs- and
more ‘particularly '- to phonograph turntable
drives. Stillmore particularly it-relates- to a
5 at two different speeds.‘
-
from one rim on the turntable. rather than from 5
and especially in the ?eld of .so-called “instan- application Serial No. 1.22.170. ?led ‘January 25,
i‘taneous” sound‘ recording‘ and reproducing, it is‘ 1937, thereby saving considerable expense in ma
customary to employ two . different speeds or ro110 - tation of the turntable carrying the, record disk.
Thus for records 12 inches 'or less in diameter a
'chinlng and construction and avoiding the neces
sitlv for reversing the direction of rotation of the 10
electric moto’l‘llsed 85 a Source Of Power as the
rotational speed of '78 PR. P.M. is commonly em-
change in speed is effected.
‘
"
,
Ployed. For records greater than 12 inches. in ' Another ‘Object of this invention‘ is to'accom
diameter '_a speed of 33% R. P. M. is used. It. is plish the foregoing objects :WhiIe'Hsine. friction‘ I
15 customary in the art'to use the same equipment idlers to transmit the driving power fromthe 15
. ‘for recording and, reproducing sound at both of‘ shaft of the electric motor used to the driving
i ‘_
these speeds; in order-to minimize overhead and
rim of..the_-turnteb1e- Use of friction drive and
investment and for- convenience,
of idlers reduces vibration and variations ‘in speed '
}
i
-
_
It is necessary that the turntablebe capable of
to. a marked extent and is deemed necessary in
20 being rotated at exactly-313M301; 7a 13,; P,
iorder to obtain goodrecording and reproduction. gm
' since these speeds .have become standard in the ,My invention Drcvides a turntable drive capable
_ . art. ‘It is highly desirable that the design of the of driving the turntable at either of two desired
.. equipment- used be such that the change in ro-
,
speeds at will, while at the same‘ time utilizing V -
tational speed of the turntable from eithef of friction drive and friction idlers between the driv
25 these speeds to the other be convenient and rapid.‘ ing shaft. and the driven rim of the turntable.
It is also desirable that it be e?ected without
Referring to the accompanyingdrawing .which
‘disassembly of any parts or without removal of portrays my invention in its preferred embodi-"
v
the
turntable.
In
addition, the vdrive for ' the
ment:
'
-
‘
.
'
.
- turntable.-must be quiet and free from vibration ' Figure 1_ isjavertical sectional view along the
30 which would affect adversely-the quality of the line‘ l_——l of Figure 2.
'
'
‘Figure :2 is a horizontal plan view partly in 30
recording or the reproduction. Moreover the
vdesig? of the drive must be such that'long-life of ' section.
_
v Figure 3 is‘ a vertical sectional view along the I
allnioving parts is obtained.
'
' _
.
.
Various expedients for obtaining theydesired, line 3—3--of Figure 2. _ >
'
'35-’ change in speed of the turntable have been here'- . ‘The two speed turntable drive contemplated 35.
by this invention utilizes an electric motor the ~
tofore suggested but so far.‘ as I am ‘aware, none.
. of them has been entirely‘ vsuccessful. Many of“
shaft of which projects vertically upward below‘
them involve gearing and undue complication to-' the turntable. The turntable is provided with a
one downwardly‘ extending driving rim which is
‘
gether with noisy anduncertain operation and 'most-‘conveniently
located
at
the
outer»
edge
of
40
4'0 short life. ' Many cause: excessive vibration‘ of the
turntable . with consequent detrimental effect .theturntable. The portion ofthe motor shaft
upon‘the recording or-r'e'production. Others in-», which extends or projects above thelowerv edge of
> volve removal of the turntable in order to ‘effect ’ this driving rim is'so constructed asito have two
the change in speed. Thislis objectionable be- portionsof different diameter, which are so cal
cause of the length‘ of time required, because of _ culated‘in ‘relation to the diameter of the tum- 45.
. ‘45
the ‘inconvenience incurred and because of the
resulting wear on the parts.
~
‘
Y
.
.
4
.
table driving rim that when this driving vrimis
.driven from the smaller portion/of the motor
" The principal object of this‘ invention is to
‘ devlseaphonograph- tumtable' drive which 'o'ver-.
comes the foregoing disadvantages and which at'50 ‘tains
many new advantages not heretofore <at-~"
- tained in this art.
-
‘
'
'
-
shaft it turns at, a speed of 33%» R. P. M. and.
that when the driving rim is driven from the
larger portion ‘ofpthe motor shaft, .it turns 'at a 50
speed of. '18 R. P.‘ M.. In placeoi' ‘the speci?c
a. - speeds mentioned, speeds approximating thereto
' ‘ ' 'Another' object of this invention isto devise may be used. Thus in the device contemplated
- =a phonograph turntable drive with which vibra- - by .this invention, I prefer to so calculate the
tio?-free anduniform operation is attained; to-
sizes of the parts that speeds-slightly in excess 16
2
2,119,218
of these standard speeds would theoretically ob
jecting solid edge portion 9. The driving rim 8'
tain so as to compensate for the slight slippage
may be formed in any desired manner and may
be machined in the turntable or may be formed
encountered in practice.
The driving force of the motor is transmitted
from the extending portion of the motor shaft
described to the turntable driving rim by means
of two rubber friction idlers disposed in a plane
parallel to the turntable. These idlers are lo
represents a motor which is of any suitable type
and is ?exibly mounted on metal plate Ii by
cated between the motor shaft and the driving
means of rubber mountings I2 and I3 which are
of any ordinary type which permit the motor
to ?oat and which absorb its vibration to a con
siderable extent. The plate II upon which the
motor I0 is mounted is pivoted at one end by
means of pivot I4 which allows the outer end
I5 of plate I I to move circumferentially in either 15
of the directions indicated by arrows I 6 and
10 rim.
One of these idlers is so disposed that up
on moving the motor shaft in the proper direc
tion the idler is driven by the smaller por
tion of the motor shaft and drives the turntable
at the lower speed, namely 331/3 R. P. M., by con
16 tact with the driving rim. The other of these
idlers is so disposed that upon moving the motor
shaft in the opposite direction the idler is-driven
by the larger portion of the motorshaft and
drives the turntable at the higher speed, namely
20 78 R P. M., by contact with thedrivirig rim.
30
40
45
60
separately and rigidly attached to the turntable
by any suitable means.
Describing now the turntable drive itself, I0
I1.
Motor mounting plate II is preferably lo
cated above the panel I8 which serves to hover
the mechanism and as a support mounting the
various parts as shown in the drawing. Thus 20
The motor shaft is movable in a direction sub~ . pivot I4 for the motor mounting plate II is pref
stantially perpendicular to a radius of the turn
erably rigidly attached to the panel LI8, as shown.
table. This movement is effected by mounting At the outer end of motor mounting plate I I is lo
the motor on a movable lever which is pivoted cated an upwardly projecting threaded member
to the panel under the turntable. The motor is
I9 which projects through panel I8. At the end 25
capable of being placed in a neutral position in .of this threaded member I9 is a knurled knob 20
which it touches neither idler. It is also ca
provided internally with threads which ?t the
pable of being moved in either direction from cooperating threads of member I9. Thus when
this neutral position so as to cause the larger knob 20 is screwed down it locks plate II in the
portion of its shaft to contact the idler for the position in which it then is. When knob 20 is 30
higher speed or so as to cause the smaller por
loose it is used to push plate II backwards and
tion of its shaft to contact the other idler for the forwards by means of member I9, thus causing
lower speed.
the motor I0 to move backwards and. forwards.
The idlers used are preferably rubber rimmed Member I9 moves through a slot 2| the ends
metal wheels which construction gives high fric
of which 22 and 23 act as stops to limit the 35
tional driving power with very little vibration movement thereof and therefore the movement
or ?uctuation in speed. The idlers used are rela
of plate II and of motor I0.
tively large in diameter compared to the motor
As the plate II is moved in either direction
shaft (either the larger or the smaller section). away from the middle neutral position, it carries
This allows the motor shaft to make good fric
the motor I0 and consequently the motor shaft 40
tional engagement with the idler. The idlers ‘indicated generally as 24 with it in the same
are relatively small compared to the size of the direction.‘ The motor shaft 24 is therefore
turntable driving rim. This allows very good moved in a direction substantially perpendicular
contact with the turntable rim.
to a radius of the turntable. In the neutral po
The idlers drive the turntable at either speed sition of the parts in which position the parts 45
from the inside of the ‘turntable rim. This al
are shown in the drawing, the motor shaft 24
lows a greater area of contact between the idler is in a neutral position in the middle of the path
and the rim than if either of them were to drive of its travel.
.
against a rim which was convex as to it._ Thus
Motor shaft 24 projects upwardly beneath the
greater torque and a more even speed is made turntable I as shown. The portion of the motor 50
possible‘ than in the construction where one idler shaft 24 which projects upwardly beyond the
drives a rim which is convex as to its, asin my lower edge 'of the driving rim 8 of the turntable
_copending application Serial No. 122,170 above
identi?ed.
~
is machined or otherwise constructed so as to
form a larger portion 25 and a smaller por
Describing now the embodiment shown in the tion 26. This construction may be attained by
drawing: I represents a rotatable circular turn
tightly ?tting sleeves which are tightly ?tted
table the top portion of which is in the usual onto the motor shaft 24, as indicated in the draw
form, with a projecting pin 2 in its center to ing, or it may be attained by machining down
accommodate the record. Downwardly pro
the projecting portion of motor shaft 24, where
60 jecting shaft 3 of the turntable is of substantial
diameter, say 1,41 .to 1 inch, and rests in the this shaft is of su?icient size to enable this to
turntable bearing 4 which is of any suitable type be done. As the motor shaft 24 is moved in the
and may comprise a closely ?tting sleeve portion ‘direction corresponding to movement of plate
II in the direction of arrow II, it drives the tum
5 and a steel ball Ii located in the rounded bot7
table at the higher speed (78 R. P. M.) by means
65 tom portion ‘I of the turntable bearing.
‘of rubber friction idler 21 which the larger por
The turntable I is of metal such as cast alu
minum and is formed or machined on its under tion 25 of the motor shaft 24 frictionally en
gages. Idler 21 then drives the turntable by
- side so that a driving rim 8 adapted to be driven
frictional engagement with the turntable driv
by frictional engagement is formed. The diam
70 eter of this driving rim is variable within wide ing rim 8.
limits, and will depend largely upon the size of
As the motor shaft 24 is moved in the direction
the turntable, it being usually most convenient corresponding to movement of plate II in the
to have it near the edge of the turntable I as direction of arrow I6, it drives the turntable I
shown in the drawing wherein the drivingv rim at the lower speed (33%; R. P. M.) by means of
75 8 islthe inner circular edge of downwardly PI'QF" rubber friction idler 28 which frictionally engages
-55
55
60
70
75.
'
‘2,119,218
‘ .‘
~
3
the smaller portion 26 of the motor shaft. .' Idler
28 then drives the turntable l by frictional-en
II by means'of knob 20' whereupon knob 20 is.
tightened to lock the plate II and ‘the motor in‘
either‘ idler, the point where the driving‘portion
is now rotating contacts the vrim 8 of the turn
table causing it to rotate at the higherv speed (78
position. As the'motor is moved in this direction
gagemen‘t with the turntable driving rim 8. .
The parts, namely, idlers 21 and 28, motor shaft ' the larger portion 25v of the projecting portion of ‘ ,
5 24 together withgit's larger and smaller portions, vthe motor shaft 24 contacts idler 21 which begins 5
_ 25 and 28, respectively, are so arranged that to‘ rotate. As the motor is continued in its move-' fwhen. the motor is in the driving position for , ment until pin l9 touches stop 23, idler 21 which
25 or 28 of the motor shaft 24 contacts the rubber
l0 ‘\‘idler 21 or 28, the point wherethe idler 21 or 28“ R. P. M.) in the direction indicated by the arrow 10 w
38 in Fig.‘ 2., When it is desired to- cause the
turntable at the other and lower speed the motor
.circle representing- the periphery of the idler 21 ‘is moved. in the other direction until pin l8
touches stop 22 and the motor drives the tum
‘or 28 are allv substantially 120° apart. This. con
'15 struction is not vital ‘to theoperation of the tabl'e through the‘ smaller portion 26 of the pro- 15
.jecting motor shaft and idler 28-. ,_ ‘
Y
,
devicebut results in the most e?lcient trans
When the apparatus is not in use, the speed
mission of the driving‘force from the motor shaft .
. 24 to the turntable rim 8 at either of the two control ‘knob 20- is moved to the center position,
freeing the idlers from the turntable rim 8 and
speeds.‘
’
‘
contacts the turntable driving rim 8 and the point
> where the axis of the idler support intersects the
20 Idlers 21 ‘and 28 are not located in vthe Isame the driving portions of the, motor shaft, relieving 120 ,
‘ horizontal plane‘. ‘Idler' .28 which contacts the . the‘pressure and lengtheningtheir life. ~'
As will be obvious the projecting portion of the . '
upper and smaller driving portion 28 of the motor
motor shaft 24 is machined to the proper sizes so
‘ shaft is ‘located in a plane above the‘plane of
that the desired speeds are obtained.
idler 21- which contacts the lower- and larger driv
25 in? portion of the motor shaft.
‘
‘
,The idlers 21 and 28 are metal wheels having
relatively thick rubber rims 29 and 38 respec~
tively, although they may be of any other con
.- struction provided they are adapted to frictionally
'of rotation of the motor shaft 24. Thus ‘when
using a motor having a speed of 1750 R. P. M., and
a driving rim having a diameter of ~16 inches, the
smaller part 28 of the motor shaft is made 0.310 .30
30 transmit the torque of the motor to the turntable
in a satisfactory manner and are of such mate
rials as to have desirable long wearing qualities.
These sizes ’
are calculated with reference to the diameter of 25". ._
,the driving rim 8 and with‘reference to the speed- -
.inch in diameter and the larger‘ part 25 is made
. 0.730 inch in'diameter.‘ These sizes cause the
turntable to rotate atspeeds of 33.6 .RhP. M. and
‘ The use of these friction idlers isjhighly desirable
since they I‘ act' as ?lters, absorbing whatever
-80' R. P._wM.,-respectively.' These increases over
,
standard‘ speeds of 78R. P. M. and 33% R. P; M. 35 -
.35, minute vibrations are set up by the motor before
they reach the turntable. Idlers 21 and 28 are
have been found sufficient to allow‘ for the slight
‘driven by straightline engagement‘with the drive ' loss in speed due to slippage.
The advantages of this drive are numerous.
'One advantage is that change‘in speed is‘ se
cured instantlyby moving a lever, it being un- 40
ing portions of motor shaft '24 ‘and drive the
' turntable i by straight lineengagement with the
40 driving rim 8 of the turntable l. -
‘
'
The idlers 21 and 28 are mounted so as to rotate
about bearings 3| and 32 at their center. . Bear
necessary to remove the turntable or anyidlers ,
'.to effect the change in speed.
ings 3| and 32 are preferably self-oiling bearings
which prevents oil, getting on the idler friction
45 surfaces and_.ruiningthem; by disintegrating the
rubber or by destroying the frictional! engage
me'nt between the idler surface and the rim or the
motor shaft.‘
.
‘
‘
I
a
'
Idlers 21 and 28 are supported in .such a man
Another ad
vantage-is that by having a neutral position in ‘
which the idlers are not under pressure, the life
of‘ the idlers is increased considerably. Also be- 45
cause it is not necessary to, remove the idlers to ‘ '
change the speeds, an‘automatic' self-oiling bear
ing can be used on them. This prevents oil
getting on the idlers and‘ruining them. By hav
50 ner that they may move outwardly so as to engage ‘ing suitable'stops to limit the motor movement,‘ 50 .
the driving rim 8. v This is accomplished by means > the correct pressure on the idlers is assured. The’
vof ?at supporting members 33 and 34, respec
“ t1vely,which are pivoted so as to be movable about
?xedpivots 35 and 38, respectively. Idler 28 is
turntable is readily removable from the machine
by simply pulling it upward, whichv gives free
access to any. of the working parts. Siricethe
turntable is driven at both speeds on its outer '55 '
,55 so mounted as to rotate about pin 38 by means of ~rim
a greater torque is developed .at both speeds
its own bearing surface 82 and pin 38 is integrally fastened to supporting member 34. Idler. 21 is so . than'is-the' case where’ the turntable is.driven
onespeed by a driving-rim which is smallin
-mounted as to rotate about pin -31 by means of-its at
own bearing surface 3| and pin 81 is integrally diameter as in my copending application Serial
No. 122,170, above identified. In‘the device 0011- 69
‘no fastened to supporting member 83.
"
templated
by this invention the turntable is ‘
_ Idler supporting member's Y33 and 34 are mov
driven at either speed by means of an idler which
able about, ?xed pivots '85 and", repectivel'y,
which are preferably‘ integrally attached to main
panel l8, as shown. I The construction shown en
65 ables theidlers to ?oat freely and to absorb vibra
tion to the fullest extent.
7
.
,
‘
-
The mode of operation of the device will be
. obvious from the foregoing description.
How
' ever, it may be'descr'ibed in ‘detail as followsi
70
,
The motor I8 is in its neutral position as shown
in the drawing. It is started by sending an elec
,tric current through it. After it‘has. come up to
speed it is moved in a direction corresponding to
movement of plate I I in the direction of arrow I1.
contacts a driving rim which is concave relative '
to it,v
This gives better frictional transmission
tothe turntable driving rim than is the case in 65'
-my application Serial No.~122,170 wherein the '
drive at the higher speed is'by means of a driv
ingirim which is. convex relative to the surface of.‘
the driving idler. Another advantage of this in
vention is that the device contemplated thereby 70 ' '
makes it unnecessary to reverse the direction of _
the‘ motor as it is moved from driving engage
ment at one speed to driving engagement at the
other speed.‘ The elimination of this reversing
75 This movement is accomplished by moving plate. switch makes for sim'plicity'of construction and 17s '
4
2,119,218
operation and lessens the cost of construction.
capable of operating at either a lower or a higher
Also it makes possible a more rapid change of
speed as it is not necessary to let the motor come
to a stop before changing to the other speed.
While generally it will be desirable to operate
the machine with the turntable in the horizontal
plane, ‘as shown in the drawing, it will be appre
speed comprising, in combination, a rotatable
circular turntable having a downwardly extend
ing circular driving rim, an electric motor so
located that its shaft projects upwardly above
.the lower edge of said driving rim, the projecting
ciated that if desirable it may be operated with
the turntable in a vertical plane. The principle
a larger circular driving portion, a lowerspeed
friction idler located between the smaller por
if) of my invention is applicable regardless of the
plane in which the turntable is located.
_
Having described my invention, what I claim
is:
1. A two-speed phonograph turntable drive
capable of operating at either a lower or a higher
speed comprising, in combination, a rotatable
circular turntable having a downwardly extend
ing circular driving rim, an electric motor so lo
cated that its shaft projects upwardly above the
portion of said motor shaft having a smaller and
tion of said'motor shaft and said driving rim, 10v
a higher speed friction idler located between
the larger portion'of said motor shaft and said
driving rim, said idlers being so supported that
they are free to move outwardly to contact said
driving rim, said motor shaft being movable in 15
either direction along a line substantially per-'
pendicular to_a radius of the turntable and be
ing so located that as it is moved in one direc
lower edge of said driving rim, the projecting
tion, its smaller portion drives the turntable at
the lower speed through said lower speed idler
portion of said motor shaft having a smaller and
a larger circular driving portion, a lower speed
friction idler located between the-smaller por
tion of said motor shaft and said driving rim, a
the other direction its larger portion drives the
turntable at the higher speed through said high
er speed idler and said driving rim.
higher speed friction idler located between the
larger portion of said motor shaft and said
driving rim, said motor shaft being movable in
capable of operating at either a lower or a higher
speed, comprising in combination, a rotatable
and said driving rim and that as it is moved in
4. A two-speed phonograph turntable drive 25
a plane parallel to the turntable in such manner . circular turntable having a downwardly extend
ing circular driving rim, an electric motor so lo
that its smaller portion may drive the turntable
at the lower speed through said lower speed idler
and said driving rim and that its larger portion
may drive the‘ turntable at the higher speed
through said higher speed idler and said driving
rim.
cated that its shaft projects upwardly above the 30
lower edge of said driving rim, the projecting
portion of said motor shaft having a ‘smaller
and a larger circular driving portion, a lower
speed friction idler located between the smaller
2. A two-speed phonograph turntable drive portion of ‘said motor shaft and said driving rim, 35
capable of operating at either a lower or a higher
speed comprising, in combination, a rotatable
circular turntable having a downwardly extend
ing circular driving rim, an electric motor so
40 located that its shaft projects upwardly above
the lower edge of said driving rim, the project
ing portion of said motor shaft having a smaller
‘and a larger circular driving portion, a lower
7 speed friction idler located between the smaller
portion of said motor shaft and said driving rim,
a higher speed friction idler located between the
larger portion of said motor shaft and said driv
ing rim, said motor shaft being movable in either
direction along a line substantially perpendicular
‘
a higher speed friction idler located between the
larger portion of said motor shaft and said
driving rim, said idlers being mounted on mov
able supporting members so that they are free
to move outwardly to contact said driving rim, 40
said motor shaft being movable in either direc
tion along a line substantially perpendicular to a
radius of the turntable and being so located that
as it is moved in one direction its smaller por
tion- drives the turntable at the lower speed 45
through said lower speed idler and said driving
rim and as it is moved in the other direction
its'larger portion drives the turntable through
said higher speed idler and said driving rim, the
to a radius of the turntable and being so located arrangement of the parts being such that when
that as it is moved in one direction its smaller
the motor shaft is in the driving position for
portion drives the turntable at the lower speed either idler the point where the driving portion
through said lower speed idler and said driving of ~the motor shaftcontacts the idler, the point
rim and as it is moved in the other direction its where the idler contacts the driving rim and the
larger portion drives the turntableat the higher » point where the axis of the idler supporting
speed through said higher speed idler and said member intersects the periphery of the idler are 55
driving rim.
"
all substantially 120° apart.
3. A two-speed phonograph turntable drive
‘
STUART J. RODGER.
Документ
Категория
Без категории
Просмотров
0
Размер файла
752 Кб
Теги
1/--страниц
Пожаловаться на содержимое документа