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Патент USA US3038592

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June 12, 1962
|_. P. FRECHETTE, JR., ETAL
3,033,532
vRIBBON FEED MECHANISM FOR BUSINESS MACHINES AND THE LIKE
Filed Dec. 25, 1960
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June 12, 1962
L. P. FRECHETTE, JR., ETAL.
3,038,582
RIBBON FEED MECHANISM FOR BUSINESS MACHINES AND THE LIKE .
Filed Dec. 23, 1960
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s Sheets-Sheet 2
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INVENTORS
LEO I? FRECHETTE JR.
ROBERT E. McGRATI-l
ARTHUR L.CHARBONEAU
' B‘PEYNOLD E. WHEELER
14.’?
'-
ATTORNEYS
M
June 12, 1962
3,038,582
L. P. FRECHETTE, JR, ETAL
RIBBON FEED MECHANISM FOR BUSINESS MACHINES AND THE LIKE
Filed Dec.
23, 1960 V
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clutch is operatively disposed between the typewriter
RIBBQN FEED MECHANISM FOR BUSINESS
MAQHINES AND TI-m LIKE
Leo I’. Frechette, In, West Hartford, Conn, Robert E.
MeG-rath, Feeding Hills, Mass, and Arthur L. Char
boneau, West Hartford, and Reynold E. Wheeler,
Farmington, (101111., assignors to Royal McBee Corpo
ration, Port Chester, N.Y., a corporation of New York
Filed Dec. 23, 1960, Ser. No. 77,887
14 Claims. (Cl. 197-160)
This invention relates to a ribbon feed mechanism for
power roll and ribbon spool drive means, said wrap spring
clutch being controlled by the cyclic operation of a uni
versal bail assembly.
A further object of the invention is to provide a novel
power operated reversing mechanism for the ribbon feed
drive means of an electric typewriter whereby a wrap
spring clutch is operatively disposed between the type
writer power roll and the ribbon drive reverse means, said
10 wrap spring clutch being controlled by the ribbon reverse
sensing linkage of the typewriter.
business machines and the like, and more particularly
Other objects and many of the attendant advantages of
relates to power operated devices for incrementally and
this invention will be readily appreciated as the same be
reversibly feeding a typewriter printing ribbon.
comes better understood by reference to the following
In many conventional typewriters the spring barrel is 15 detailed description when considered in connection with
connected so as to not only incrementally drive the car
the accompanying drawings in which like reference nu
riage but also to rotatably drive the ribbon spools and/ or
merals designate like parts throughout the ?gures thereof
to reverse the ribbon feed mechanism. This type of rib
bon feed mechanism is undesirable in electric typewriters
and wherein:
FIGURE 1 is a perspective view of the instant power
where high speed typing occurs. If during such high
speed operations the spring barrel is overloaded by having
operated mechanisms for incrementally actuating and for
posite longitudinal direction.
made, such means including a pair of vertically disposed
reversing the typewriter ribbon drive means.
to rapidly drive the ribbon feed mechanism ‘as well as the
FIGURE 2 is a front elevational view of the apparatus
record supporting carriage then it may not be able to
of FIGURE 1.
impart an intermittent letter feeding movement to the car
FIGURE 3 is a fragmentary view in partial section and
riage which is vfast enough to accommodate the relatively 25 shows the construction of a wrap spring clutch arrange
‘high printing speeds. In that there are several readily
ment which is adapted to operatively couple the type
available power operated elements in an electric type
writer power roll to the ribbon drive means.
writer it is desirable to use one or more of these elements
FIGURE 4 is a partial side elevational view of the
to incrementally drive the ribbon feed device and/or to
means for controlling the operation of the wrap spring
reverse the ribbon feed drive means.
‘clutch of FIGURE 3.
One object of the instant invention is to provide an
FIGURE 5 is a perspective view illustrating the power
improved power operated ‘device for incrementally feed
‘operated ribbon drive reversing cam.
ing the printing ribbon of a business machine.
FIGURE 6 is a side elevational view in partial section
Another object of the invention is to provide an im
and shows the control linkage for another ‘wrap spring
proved power operated device for reversing the ribbon
clutch arrangement which is adapted to operatively couple
feed mechanism of a business machine.
the typewriter power roll with the ribbon drive reversing
Another object of the invention is to provide a novel
means.
power operated ribbon feed reversing mechanism for busi
The conventional structure which comprises the me
ness machines whereby the reversing mechanism is cam
chanical environment for the instant invention will be
operated in one direction and spring operated in the op 40 described ?rst. Referring to FIGURES l and 2 there is
posite direction.
shown a cooperating pair of ribbon spools 10 and 11
Another object of the instant invention is to provide
that are operatively mounted at the respective upper ends
a novel power operated device for incrementally feeding
of a pair of vertically disposed shafts 12 and 13. The
the printing ribbon of an electric typewriter or the like
spools 10 and 11 are adapted to carry a printing ribbon
whereby a clutch is operatively connected between the 45 R in the usual manner so that said ribbon may be lon
typewriter power roll and ribbon spool drive means.
gitudinally fed :back and forth in front of the printing
Another object of the instant invention is to provide a
Zone or point of the machine. Shafts 12 and 13 are
novel power operated device for incrementally feeding
rotatably mounted in the machine frame 14 by any suit
the printing ribbon of an electric typewriter or the like
able means which may include the ?xed frame brackets
whereby a clutch is operatively connected between the 50 15 and 16 and are provided at their respective lower ends
with bevel gears 17 and 20. Drive means are provided
typewriter power and spool drive means, said clutch being
controlled by an escapement mechanism that is cyclically
for rotating the ribbon spool shafts, such means includ
operated by the typewriter universal bail.
ing an axially movable drive shaft 21 which is rotatably
supported in the machine frame, as by said frame brack
Another object of the instant invention is to provide a
power operated reversing arrangement for the ribbon feed 55 ets, and which has ?xed thereon a pair of axially spaced
bevel gears 22 and 23 that are adapted to alternately
drive means of an electric typewriter whereby the said
mesh with said gears 17 and 20‘ respectively in response
reversing arrangement is biased to a normal position
to an axial shifting movement of said drive shaft 21.
wherein the printing ribbon may be fed in one longitudinal
Arranged for cooperation with said ribbon spools are a
direction and whereby the said reversing arrangement may
be power driven to and then latched in an alternate posi ' '60 pair of ribbon feed sensing devices which are operated
when a reversal of the ribbon feed direction should be
tion wherein the printing ribbon may be fed in the 0p
Another object of the invention is to provide a novel
control levers 25 and 26 that are pivotally mounted on
means of an electric typewriter whereby a wrap spring
the axial displacement of shaft 21 serves to reverse the
the machine frame as by studs 27 and 30. The control
power operated ribbon feed reversing control mechanism
levers are provided at their upper ends with bent oif arms
65
for an electric typewriter whereby the typewriter power
31 and 32 which are respectively disposed adjacent the
roll is intermittently coupled to said mechanism under the
lower ?anges of said ribbon spools 10 and 11, said levers
control of the ribbon feed sensing devices of said type
also being spring biased to normal clockwise positions,
writer.
FIGURE 1, by means of springs 33 and 34 respectively.
Another object of the invention is to provide a novel
As will be apparent the rotational movement of shaft
70
power operated mechanism for the ribbon feed drive
21 serves to longitudinally feed the printing ribbon while
3,088,582
3
4
direction of longitudinal feed of the ribbon as will be
more ‘fully described below. The construction and op
tion occurs. In the normal condition of the parts, as il
lustrated in FIGURES l, 2 and 4, the pallet tooth 50
prevents the clockwise movement of both the wheel 43
and the attached right end of Wrap spring 46 and thus
releasably retains the clutch wrap spring 46 in an opened
or disengaged condition.
In operation each time one of the type bars of the
eration of the above described apparatus is more or less
conventional in nature and need not be further discussed
in detail here.
In accordance with the present invention, shaft 21
is axially biased to a normal left hand position, FIGURE
2, by means of a spring 36 that is operatively disposed
‘between the bevel gear 22 and the adjacent end of
machine partakes of a printing stroke the pallet 47,
through link 54 and bail assembly 55, will be oscillated
Under these conditions the bevel gears 20 10 through one cycle. This cycle will permit the wheel 43
to rotatably advance in a clockwise direction, FIGURE
4, a distance equivalent to one tooth on said wheel. Dur
incrementally driven. The shaft 21 is adapted to be
ing the initial part of this advance the wrap spring 46
displaced to the right, FIGURES l and 2, to a latched
‘bracket 15.
and 23 are normally engaged and the spool 11 may be
will be free to twist itself into its engaged condition and
position wherein the bevel gears 17 and 22 will be op
in that gear 42 will thereby be operatively coupled to
eratively engaged so that the spool 10‘ may be incre
the power roll shaft, the drive shaft 21 will be driven
mentally driven. The detenting means to retain the shaft
through gear 41 so as to rotate the ribbon spool 11,
21 in its latched or right hand position against the action
spool 10 being free to pay out the printing ribbon Wound
of spring 36 comprises a collar 37 ?xed to said shaft
thereon. After the spool 11 has been driven by the
and a cooperating depending ?nger 38 formed on the
lower end of the control lever 26. The depending ?nger 20 power roll through a relatively short arcuate distance the
pallet tooth 50 will intercept the next one of the wheel
38 is normally biased into engagement with the cylin
teeth 52 thereby causing the wrap spring 46 to be moved
drical periphery of the collar 37 as indicated in FIGURES
to its disengaged condition. Thus during each successive
1 and 2; however, when shaft 21 is axially displaced to
printing operation of the typewriter the ribbon feed drive
the right the spring 34 will displace the control lever
?nger 38 towards the shaft 21 so the right hand edge, 25 shaft 21 is momentarily coupled to the rotating power
roll 40 so as to incrementally feed the printing ribbon.
‘FIGURE 2, of said ?nger moves into detenting relation
with respect to the adjacent left hand radial ‘face of col
Between the ribbon feed stepping actions if any random
lar 37. Subsequently when the ribbon has been payed
counter clockwise movement, FIGURES l and 4, of gear
off of spool 11 the control lever 26 will be displaced in
42 occurs which allows engagement of the Wrap spring
a counter clockwise direction, FIGURE 1, by the asso 30 clutch, such engagement will merely serve to slightly
ciated spool ear 35 so as to move ?nger 38 out of de~
rotate the gear 42 in a clockwise direction which in turn
tenting engagement with the collar 37 and thus permit the
spring 36 to displace the shaft 21 to its normal FIGURE
will immediately disengage the clutch. Thus the rotating
power roll normally assists in maintaining the wrap
spring clutch in a disengaged condition.
1 position so as to condition the drive arrangement so
that the ribbon is fed back onto spool 11.
The instant invention provides a power operated rib
35
bon feed mechanism for incrementally rotating the drive
When most of the printing ribbon has been wound
onto the spool 11 the shaft 21 must be axially displaced
to its latched or right hand position, FIGURE 1, against
shaft 21 and another power operated control or ribbon
the action of spring 36 so as to reverse the direction of
‘feed reversing mechanism for axially shifting the shaft
ribbon feed. The power operated means for accomplish
ing this comprises a ribbon feed reversing control bail
21 to its right hand position. These power operated
mechanisms each include a wrap spring clutch through
which the related mechanism may be operatively coupled
to the power roll of the typewriter. The clockwise mov
ing power roll 40 shown in the drawings may be ro
tatably supported and driven by any suitable means.
The means for rotatably connecting the shaft 21 to the
power roll comprises a gear 41 which is ?xedly secured
to the end of shaft 21 and which meshes with an axially
elongated gear 42. A toothed escapement wheel 43 is
56, FIGURES 1 and 2, having vertical leg portions that
are mounted on the shaft 21 between the gear 41 and the
bevel gear 22. The central body portion of bail 56 is
formed with an elongated slot 57 into which extends
a detenting tab 60‘ which is formed on the adjacent
bracket 15 or on any other suitable part of the machine
frame. ‘In this way the bail 56 is substantially axially
?xed with respect to the shaft 21 and hence is capable
of axially shifting the same but yet will accommodate the
disposed coaxially adjacent gear 42, the wheel and gear 50 rotational movement of said shaft 21. The lower end
being rotatably mounted on the reduced end 44, FIGURE
of the depending bail leg portion 61 is adapted to laterally
3, of the power roll shaft 45 and being respectively
engage the radial face of the helical camming surface 62
rotatably secured to the opposite ends of wrap spring
of a cam 63, FIGURES 1, 2 and 5, that is rotatably
46, said wrap spring comprising a clutch means between
mounted on the power roll shaft 45. A clutch wrap
the power roll and the spool drive means.
The clutch
wrap spring coil diameter is normally slightly less than the
diameter of the reduced end v44 of the power roll shaft and
hence the wrap spring tends to rotate the load driving gear
42 and the wheel 43 in counter clockwise and clock
wise directions respectively so that the wrap spring coils
are always attempting to operatively grip the outer cy
lindrical surface of the said reduced shaft end 44. A
pallet 47 is rotatably mounted on the machine frame by
means of a suitable stud 48 and has formed at its lower
end two teeth 50 and 51 which are adapted to alternately
spring 64 is mounted on the power roll shaft 45 and has
one end 65, FIGURE 6, secured in a radially disposed
hole 66 formed in the cam 63 while the other spring
end 67 is radially disposed and normally overlies a bent
off ear 70 formed on the depending tooth 71 of a pallet
72 that is integrally formed at the lower end of said
control lever 25. The radial end 67 of the wrap spring
64 together with the bent off ears 70 and 73 of the pallet
teeth 71 and 74 operatively de?ne a conventional type
escapement device which in operation is similar in effect
65 to a one revolution clutch in that a 360 degree rotation
cooperate with the successive teeth ‘52 of the escapement
of the cam 63 is permitted in response to each cyclic os
wheel 43 so as to permit gear 42 to incrementally rotate,
cillation of the pallet 72. The clutch Wrap spring 64
the mode of cooperation here being similar to that in any
is nominally smaller in coil diameter than the cylindrical
conventional type of escapement mechanism. Pallet 47
surface of the power roll shaft 45 and hence tends to
is lightly biased in a counter clockwise direction by 70 move into an engaged condition wherein it circumferen
means of a spring 53, FIGURE 4, and is articulately con
tially grips said surface of shaft 45. The bent-off car
nected to a link 54 which is operatively connected so as
70 however normally maintains the clutch wrap spring
to be actuated by the operation of a conventional type
64 in a disengaged condition. Any random counter
universal bail assembly 55, the latter being cyclically
clockwise movement, FIGURE 1, of cam 63 which moves
operated in the usual manner each time a typing opera 75 the wrap spring 64 to its engaged condition will immedi
3,038,582
6
ately cause a slight clockwise rotation of said cam which
in turn moves the wrap spring back to a disengaged con
so as to power shift said control means and thereby permit
dition. Thus the rotating power roll 40 also‘ acts to
assist in maintaining this clutch wrap spring in its .dis
engaged or opened condition.
.In the operation of the above described power operated
integral bent ‘off ear 70 will swing out from under the
2. In a business machine having a pair of rotatably
mounted ribbon spools carrying a printing ribbon that is
adapted to be fed longitudinally past the printing zone of
the machine, drive means for rotating said spools, shift
able control means for said drive means for controlling
the effective direction of operation of said drive means
whereby said ribbon may be fed in either longitudinal
direction, and a continuously rotating power driven mem
ber, and a bail assembly cyclically operable during each
radially disposed end 67 of the wrap spring 64 thereby
permitting the latter to grip the clockwise rotating power
prising clutch means operatively connected between said
ribbon ‘feed reversing control mechanism when the control
lever 25 is pivotally displaced in a counter clockwise
direction, FIGURE 1, due to the fact that most of the
priting ribbon has been wound onto the spool 11, the
the driving of said spools in the other operative direction.
printing operation of the machine; the improvement com
roll shaft 45 so as to temporarily rotatably couple the
continuously rotating member and said drive means, and
power roll and the cam. 63. During the resultant 360 15 clutch control means operable in response to the actua
degree rotational movement of cam 63 the helical cam
tion of said ball assembly ‘for engaging said clutch means
ming surface ‘62 will displace the depending bail leg 61
for a predetermined period, said clutch means including
and hence shaft 21 to the right, FIGURE 1, against the
a wrap spring and said clutch. control means including an
action of spring 36 until the bevel gears 20 and 23 move
escapement device which controls one end of said wrap
out of mesh ‘and gears 17 and 22 move into mesh; the 20 spring.
shaft collar and the depending ?nger 38 of control lever
3. In a business machine having a pair of rotatably
26 then becoming effective to hold shaft 21 in this axially
mounted ribbon spools carrying a printing ribbon that is
shifted position as above described. If the oscillatory
adapted to be fed longitudinally past the printing zone of
motion of control lever pallet 72 is relatively slow the
the machine, drive means for rotating said spools, shift
wrap spring end 67 may be intercepted by the bent off 25 able control means for said drive means for controlling
car 73, however even in this case the drive shaft 21 will
the effective direction of operation of said drive means
have been shifted to its right hand position in that the
whereby said ribbon may be ‘fed in either longitudinal
effective camming surface 62 extends about only a rela
direction, and a continuously rotating power driven mem
tively short portion of the periphery of the cam 63. Due
ber, and a ribbon feed sensing device normally operated
to the elongated character of gear 42 the shaft 21 may 30 when the direction of feed of said ribbon requires reversal;
still be rotatably driven from the power roll after shaft
the improvement comprising a clutch operatively con
21 has been shifted to its latched position.
nected between said driven member and said control
The bevel gears 17 and 22 will remain in engagement
means, and a clutch control means responsive to the
until the ensuing intermittent rotary indexing movement
operation of said ribbon {feed sensing device for engaging
of the drive shaft 21 rotates the spool 10 to the extent 35 said clutch for a predetermined period so as to power
necessary to collect most of the printing ribbon. When
shift said control means.
about all of the ribbon has played out from spool 11
4. Apparatus as de?ned in claim 3 wherein said clutch
the control lever 26 will be actuated thereby removing
includes a wrap spring, and wherein said clutch control
the detenting effect of ?nger 318 on the collar 37 where
means includes an escapement device which controls one
upon shaft 21 is free to axially move to the left under
end of said wrap spring. a
action of spring 36 so as to disengage bevel gears 17'
5. In a business machine having a pair of rotatably
and 22‘ and re-e'ngage bevel gears 20 and 23. This action
mounted ribbon spools carrying a printing ribbon that is
will cause the printing ribbon to again be fed back onto
‘adapted to be longitudinally fed past the printing zone of
the spool 11 during subsequent typing operations.
the machine, drive means for rotating said spools, shift
In accordance with the above described apparatus 45 a'ble control means for said drive means for controlling
the printing ribbon is power driven longitudinally back
the effective direction of operation of said drive means
and forth across the printing point by apparatus that is
so that said ribbon may be fed in either longitudinal di
intermittently actuated directly from the typewriter power
rection, a ribbon feed sensing device normally operated
when the direction of ‘feed of said ribbon requires reversal,
peatedly automatically reversed by apparatus which is 50 a bail assembly cyclically operable during each printing
also power actuated directly from the typewriter power
operation of the machine, and a continuously rotating
roll. The instant structure has been extensively tested
power driven member; the improvement comprising a
roll.
Likewise this ribbon feed drive apparatus is re
and ‘has been found to be very e?'icient and to have a
?rst clutch means connected between said power driven
long life of reliable performance.
member and said drive means and operative in response
While there is in this application speci?cally described 55 to the cyclic operation of said bail assembly to inter~
one form which the invention may assume in practice, it
mittently feed said printing ribbon in one longitudinal
will be understood that this form of the same is shown
direction, and a second clutch means connected between
for purposes of illustration only and that the invention
said power driven member and said control means and
may be modi?ed and embodied in various other forms
operative in response to the operation of said ribbon feed
without departing from its spirit or the scope of the ap 60 sensing device so as to power shift said control means
pended claims.
and thereby reverse the direction of longitudinal feed of
The invention elaimed is:
said printing ribbon.
1. In a business machine having a pair of rotatably
6. Apparatus as de?ned by claim 5 wherein said first
mounted ribbon spools carrying a printing ribbon that is
clutch means includes a wrap spring one end of which is
adapted to be fed longitudinally past the printing zone of 65 controlled by said cyclic operation of said bail assembly,
and wherein said second clutch means includes a wrap
the machine, drive means for rotating said spools, shift
spring, one end of which is controlled by the operation
a'ble control means for said drive means for controlling
the effective direction of operation of said drive means
of said ribbon feed sensing device.
7. In a typewriter having a pair of rotatably mounted
whereby said ribbon may be fed in either longitudinal
direction, and a continuously rotating power driven mem 70 ribbon spools carrying a printing ribbon that is adapted to
be fed longitudinally past the printing point of the ma
ber; the improvement comprising a ?rst clutch means (for
intermittently coupling said power driven member to said
chine, drive means for rotating said spools, control means
drive means so as to incrementally drive said spools in
for said drive means for controlling the effective direction
of operation of said drive means so that said ribbon may
one operative direction, and a second clutch means for
coupling said power driven member to said control means 75 be ‘fed in either longitudinal direction, a universal bail
3,038,582
7
8
assembly cyclically operable in response to the successive
tween said power roll and said drive means, and clutch
control means cyclically operated in response to the op
printing operations of the typewriter, a ribbon feed sens
ing device normally operated when the direction of longi
eration of said bail assembly for controlling the opera
tudinal feed of said ribbon requires reversal, and a con
tion of said second clutch means.
tinuously driven power roll; the improvement comprising
10. Apparatus as de?ned by claim 9 wherein each of
a ?rst clutch means operatively connected between said
power roll and said drive means, an escapement mecha
said clutch means includes a wrap spring, and wherein
said clutch control means for said second clutch means in
cludes an escapement device.
11. Apparatus in accordance with claim 1 wherein
nism cyclically operated by said universal bail assembly
‘for controlling the engagement of said clutch means and
the resultant incremental feeding of said ribbon, and a 10 said shiftablc control means includes a shift arm and said
second clutch means includes a driven element provided
second clutch means operatively connected between said
with a cam adapted to engage said arm when said element
power roll and said control means and controlled by the
operation of said ribbon feed sensing device for power
shifting said control means and reversing the direction of
the ribbon ‘feed.
8. In a typewriter having a pair of rotatably mounted
ribbon spools carrying a printing ribbon that is adapted to
be longitudinally fed past the printing pointof the ma
chine, drive means for rotating said spools, shiftable con
trol means for said drive means having normal and
shifted operative positions for respectively controlling the
effective direction of operation of said drive means
whereby said ribbon may be fed in either longitudinal
direction, a pair of ribbon feed sensing devices respec
tively associated with said ribbon spools and each being
normally operated when the direction of ‘feed of said
ribbon requires reversal, a bail assembly cyclically oper
able in response to each successive printing operation of
the typewriter, and a continuously driven power roll; the
improvement comprising clutch means operatively con 30
nected between said power roll and said control means,
means ‘biasing said control means to a normal position,
means controlled by one of said ribbon feed sensing de
vices for engaging said clutch means so that said control
means is displaced to a shifted position, and detent means
connected to the other of said ribbon feed sensing devices
for releasably retaining-said control means in said shifted
position, the subsequent operation of said other ribbon
feed sensing device effectively releasing said control
means for movement back to its said normal position
under the action of said biasing means.
9. Apparatus as de?ned by claim 8 additionally com
prising a second clutch means operatively connected be
is driven upon engagement of said second clutch thereby
to shift said control means.
12. Apparatus in accordance with claim 1 wherein
said shiftable control means includes a shift arm and said
second clutch means includes a driven element provided
with a cam adapted to engage said arm when said element
is driven upon engagement of said second clutch thereby
to shift said control means, and detent means operatively
associated with said shiftable means to hold said shiftable
means in one of its shifted positions.
13. Apparatus in accordance with claim 1 wherein
said shiftable control means includes a shift arm and said
second clutch means includes a driven element provided
with a cam'adapted to engage said arm when said element
is driven upon engagement of said second clutch thereby
to shift said control means, and detent means operatively
associated with said shiftable means to hold said shiftable
means in one of its shifted positions, and ribbon spool
operated means for releasing said detent means from its
holding position thereby to permit shifting of said shift
able means to its other shifted position.
14. Apparatus in accordance with claim 1 including
means operated by one of said ribbon spools for effecting
engagement of said second clutch means when the ribbon
is substantially unwound from said one spool.
References Cited in the ?le of this patent
UNITED STATES PATENTS
2,565,985
2,616,547
Norton et a1 _________ __ Aug. 28, 1951
Dodge ______________ __ Nov. 4, 1952
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