US3444979A - Ribbon feeding device for a variable spacing typewriter - Google Patents

Description

B. FRANCISCO May 20, 1969 mason FEEDING nnvrcn FOR A VARIABLE SPACING TYPEWRITER Sheet Z or 2 Filed June 2. 1966 lllllll HHHHHH IHH mm mvsmom BERNARD'NO FRANCISCO BY M AGENT May 20, 1969 s. FRANCISCO 3,444,979

RIBBON FEEDING DEVICE FOR A VARIABLE SPACING TYPEWRITER Sheet 4? Filed June 2, 1966 Fig. 2

INVENTOR. B ERNARDINO FRANCISCO United States Patent US. Cl. 197-451 3 Claims ABSTRACT OF THE DISCLOSURE A variable spacing typewriter is provided with a carbon ribbon feeding device adapted to advance the ribbon a minor length when a first group of types is printed and a major length when a second group of types is printed. The ribbon is advanced through a ratchet wheel cooperating with a pair of parallel pawls, which are reciprocated upon printing each type, whereby a first pawl advances the ribbon a first increment during the forward stroke of the pawls, whereas the other pawl advances the ribbon a second increment during the return stroke thereof. A spacing selector is adapted to disable said other pawl upon selecting the spacing of any type of said first group.

This invention relates to a ribbon feeding device for a variable spacing typewriter, comprising means normally effective for feeding a predeterminate portion of ribbon in the printing advancing direction upon printing each character.

In the variable spacing typewriters, particularly in the case wherein carbon ribbon is used, it is useful to feed the ribbon through variable strokes according to the width of the printed character. There are known difierential ribbon feeding devices, wherein the ribbon is fed proportionally to the carriage spacing corresponding to each printed character. These devices are intricate and expensive since the carriage generally may advance through a variable number of unit spacings from two to six, whereby the ribbon feeding device needs to advance the ribbon through one of five different lengths.

To obviate this disadvantage, a feeding device has been proposed, wherein a member for feeding the ribbon is predisposed before the printing for effecting two different strokes corresponding to two different ribbon portions. Therefore, after the printing a time corresponding to the longer stroke must be provided for feeding the ribbon, whereby the speed of the machine is reduced.

A ribbon feeding device is also known which comprises a ratchet wheel and a pair of simultaneously reciprocating pawls to rotate the wheel. However, this device is unable to variably advance the ribbon relatedly to the spacing effected by the carriage.

The primary object of the invention is to provide in a proportionally spacing typewriter an eflicient ribbon feeding device which substantially avoids waste of carbon ribbon.

Another object of the invention is to provide for a proportionally spacing typewriter a ribbon feeding device which is inexpensive to manufacture, reliable in operation and feeds the ribbon efficiently through extents correlated to the characters being typed.

The invention is applied to a variable spacing type- Writer which includes a usual set of types, a set of intermediate operating members for said types, and a spacing control mechanism governed by the said intermediate members to execute incidental to each typing operation a variable, proportional space regulating movement correlated to the particular type that is being operated. -If the variable space requirement for the character being typed is greater than a certain size, the staetd control mechanism will execute an appropriate stroke transgressing a certain extent of operation. On the other hand if the variable space requirement for the character being typed is below said certain size, the stated control mechanism will execute an appropriate stroke short of transgressing said certain extent of operation. On the other hand if the variable space requirement for the character being typed is below said certain size, the stated control mechanism will execute a stroke short of transgressing said certain extent of operation.

A carbon ribbon feeding device is governed by said control mechanism so that if the latter executes a stroke transgressing said certain extent of operation, a ratchet wheel of a ribbon feeding device, through the medium of a first pawl, will receive a ribbon feeding motion from a power operable means during a forward stroke thereof, and further, through the medium of another pawl will receive a supplemental ribbon feeding motion from the power operable means during a return stroke thereof. On the other hand, if said control mechanism executes a stroke short of transgressing said certain extent of operation, the said ratchet wheel will receive a ribbon feeding motion from the power operable means only during the forward stroke of the power operable means, the said other pawl being held in a disabled condition due to the control mechanism having moved short of transgressing said certain point of operation.

Specifically said first and said other pawl are arranged for feeding cooperation with said ratchet wheel at two diametrically opposite sides thereof. Furthermore, said first pawl and the other pawl are adapted to feed said ratchet wheel respectively during the forward and the return stroke of said power operable means.

However, in any typing operations in which said stated control mechanism does not transgress said certain extent of operation, the said second pawl is held disabled so that no supplemental ribbon feeding operation will materialize.

This characteristic of the invention will become apparent from the following description of a preferred embodiment thereof and from the accompanying drawings, wherein:

FIG. 1 is a right hand partial longitudinal sectional view of a variable spacing typewriter incorporating a ribbon feeding device according to the invention; and

FIG. 2 is a partial plan view of the typewriter of FIG. 1.

With reference to FIG. 1, the variable spacing typewriter comprises a set of type actions, each one having an intermediate lever 3 fulcrumed on a stationary shaft 4 and connected through a link 6 to a type bar 7. This latter is fulcrumed on a wire rod 8 carried by a conventional basket 9. Furthermore the typewriter comprises a shaft 11 continuously rotated counterclockwise by an electric motor not shown in the drawing. A sleeve 12 is adapted to be cyclically rotated degrees by the shaft 11 at the depression of each printing key in the manner described in the United States Letters Patent No. 3,151,722. A pawl 13 fulcrumed on the corresponding intermediate lever 3 engages then a universal bar 14, which through a link 15 is connected to a lever 16 fulcrumed on a stationary pivot 17 and cooperating with a cam 18 secured to the sleeve 12. Then the cam 18 releases the lever 16, thus causing a spring 19 to rock the bar 14 counterclockwise, whereby the lever 3 is rocked also counterclockwise and causes the type bar 7 to strike against the conventional platen 20.

Furthermore, the typewriter is provided with a variable spacing control mechanism comprising a lever 22 fulcrumed on the pivot 17 and urged by a spring 21 to contact cam 18. The lever 32 is connected through a link 23 to a universal bar 24 fulcrumed at 25 and adapted to predispose a spacing corresponding to the character to be printed in the manner described in the United States Letters Patent No. 3,288,262, wherein the bar 24 is indicated by the numeral 183. To this end the universal bar 24 is provided with a set of teeth 26 (FIG. 2) having a variable length and each one adapted to sense a projection 27 (FIG. 1) of the intermediate lever 3 of the corresponding type action when operated. The universal bar 24 when rocked counterclockwise may be arrested at four different positions to correspondingly select a spacing variable from two to five unit spacings. Therefore the stroke of the universal bar 24 is substantially proportional to the spacing effected by the carriage. It is to be pointed out that the conventional space bar, not shown in the drawing, does not cause a cycle of the sleeve 12, but it operates the escapement mechanism independently from the universal bar 24.

The typewriter is provided with a device for feeding a carbon ribbon 28 in front of the platen 20. The ribbon 28 (FIG. 2) is supplied by a spool not shown in the drawing and is fed in the printing advancing direction, that is from left to right through a conventional ribbon vibrator 29. This latter is fulcrumed on an arm 101 secured to a shaft 99 rotatably mounted on the machine frame. The ribbon 28 is then guided by a roller 30 and is finally wound on a winding spool 31. The ribbon feeding device comprises a pair of friction rollers 32, 34 of which the roller 32 is secured to a vertical pivot 33, whereas the roller 34 is rotatably mounted on a pin 35 carried by a lever 36. This latter is fulcrumed on a stationary pivot 37 and is urged counterclockwise by a spring 38. The lever 36 is also provided with a projection 39 manually operable from the top of the machine, for inserting a fresh ribbon between the rollers 32, 34.

The spool 31 is frictionally driven by a flange 40 secured to a gear 41 rotatably mounted on a stationary shaft 42. The gear 41 meshes with a second gear 43 rotatably mounted on the pivot 37 and meshing with a third gear 44 secured to the pivot 33. This latter is connected through a pair of friction disks, generically indicated by the numeral 45 (FIG. 1), to a vertical shaft 46 rotatably mounted on the machine frame. Secured to the lower end of the shaft 46 is a ratchet wheel 47 cooperating with a spring urged locking member 48 (FIG. 2)

The feeding device is provided with normally effective first means comprising a first pawl cooperating with ratchet wheel 47 and formed of a lug 49 of a slide 51 slidably mounted on a stationary shaft 52 (FIG. 1). The feeding device is also provided with normally ineffective second means comprising a second pawl cooperating with the ratchet wheel 47 at the diametrically opposite side with respect to the lug 49 and formed of a lug 57 (FIG. 2) of a second slide 58 slidably mounted on the shaft 52 (FIG. 1).

The two slides 51 and 58 are simultaneously reciprocated by a common member or bar 53 through a forward and a return stroke, the forward stroke being efiected susbtantially before the printing, the return stroke being effected after the printing. Therefore, the lug 57 is adapted to rotate the ratchet wheel 47 before the printing, and the lug 49 is adapted to rotate the wheel 47 after the printing. More particularly, the slide 51 is rotatable on the bar 53 and axially shiftable thereon, whereas the slide 58 is provided with a slot 60 engaging the bar 53 so as to enable the bar 53 to be rearwards (rightwards in FIG. 1) moved with respect to the slide 58, and this latter to be rotated and axially shifted on the bar 53. A spring 61 (FIG. 2) tensioned between the slides 51 and 58 urges said slides to contact two flanges 62 of the bar 53, and the lugs 49 and 57 to engage the ratchet wheel 47. The bar 53 is secured to a pair of arms 55 and 54 of a bail 56 fulcrumed on a stationary shaft 71.

Yieldable connecting means are provided between the bar 53 and the slide 58. Particularly said connecting means comprise a spring 63 (FIG. 1) tensioned between the arm 55 of the bail 56 and the slide 58. This latter is also provided with a lug 64 contacted by a lever 66 fulcrumed on the shaft 52, under the urge of a spring 65. The lever 66 is provided with an element or shoulder 67 normally locatedin the path of the lug 64. Finally, the lever 66 is provided with a projection 68 adapted to be engaged by a lug 69 of the lever 22 when the universal bar 24 is rocked for predisposing at least five unit spacings.

Furthermore, the bail 56 is provided with a third arm 72 pin and slot connected with a lever 73 fulcrumed at 74 and normally urged by a spring 76 to contact a cam 77 of the sleeve 12. A further arm 78 of the bail 56 is provided with a lug 79 adapted to cooperate with a shoulder 81 of a lever 82 fulcrumed at 83. The lever 82 is normally urged by a spring 84 to contact a pin 86 of a lever 87 fulcrumed at 88 and provided with a pin 89 cooperating with a spring urged locking member 91. The lever 87 is connected through a link 92 to a lever 93 fulcrumed at 94 and having a manually operable projection 95. Finally, the lever 87 is provided with a shoulder 96 adapted to cooperate with a lug 97 of a lever 98 secured to the shaft 99 (FIG. 2). The lever 98 is linked with a link 102 provided with a slot 103 normally urged by a spring 104 to contact a pin 105 of the arm 72 of the bail 56.

The ribbon feeding device operates as follows.

During each cycle of the sleeve 12, the cam 77, through the lever 73, rocks the bail 56 at first counterclockwise and then clockwise. Assuming that the lever 93 is located in the position of FIG. 1, the spring 104 moves the link 102 downwards, and rocks the lever 98 clockwise together with the shaft 99 and the arm 101. The vibrator 29 is thus displaced upwards so as to insert the ribbon 28 between the type bar 7 and the platen 20. Furthermore, the bar 53 of the bail 56 is displaced at first rearwards (rightwards in FIG. 1) and then forwards, a stroke corresponding to two steps of the ratchet wheel 47 (FIG. 2)

In the case the universal bar 24 is arrested by the projection 27 of the operated type action in a position corresponding to a number of unit spacings from two to four, the lug 69 (FIG. 1) of the lever 22 does not engage the projection 68 of the lever 66. Then the shoulder 67 of the lever 66 arrests the slide 58 after such a stroke as to cause its lug 57 (FIG. 2) to advance the ratchet wheel 47 about half a step before the printing is effected. On the contrary, the slide 51 is positively drawn rearwards by the bar 53 about two steps of the ratchet wheel 47, whereby the lug 49 engages the second tooth starting from the one engaged at the beginning of the cycle.

After the printing, the cam 77 (FIG. 1) causes the spring 76 to return the lever 73 counterclockwise and the bail 56 clockwise. Then the pin 105, through the link 102, the lever 98 and the arm 101, restores the vibrator 29 downwards, while the bar 53 restores the slides 51 and 58 forwards. Now the lug 49 (FIG. 2) of the slide 51 rotates the ratchet wheel 47 clockwise one step and a half, whereby the ratchet wheel 47 in the whole is rotated two steps, corresponding to a predetermined portion of ribbon 28.

On the contrary, in the case the universal bar 24 is arrested in a position corresponding at least to five unit spacings, the lug 69 (FIG. 1) engages the projection 68 of the lever 66 which is rocked clockwise and removes its shoulder 67 out of the path of the lug 64.

Now, when the bail 56 is rotated counterclockwise, the slide 58 is no longer arrested and the lug 57 (FIG. 2) previously advances the ratchet wheel 47 one step and a half before the printing, while the lug 49 engages the third tooth starting from the one engaged at the beginning of the printing cycle. After the printing, the lug 49 is returned forwards and advances the ratchet wheel 47 one step and a half as in the preceding case, whereby in the whole the ratchet wheel 47 is rotated three steps instead of two steps, thus advancing an additional portion of the ribbon 28.

It is thus clear that, neglecting the half a step advancement caused in any case by the lug S7 to make sure the engagement of the lug 49 between two teeth of the ratchet wheel 47, the pawl 49, 51 is normally effective for feeding a predeterminate portion of ribbon in the printing advancing direction upon printing each character, whereas the pawl 57, 58 is normally ineffective for previously feeding an additional portion of ribbon, and is rendered effective by the means 22, 69 when a character requiring at least a predetermined spacing is conditioned for printing. Since the ribbon is advanced from left to right the additional portion previously fed predisposes at left a sufficient length of fresh ribbon for printing the widest characters.

If the ribbon 28 is to be prevented from being fed, for example, for cutting a stencil, the lever 93 (FIG. 1) must be rocked clockwise. Then the lever 93 through the link 92 rocks the lever 87 counterclockwise, to the position shown by broken lines in FIG. 1. The shoulder 96 of the lever 87 is thus brought into the path of the lug 97, while the pin 86 causes the lever 82 to temporarily contact the lug 79.

Thereafter, upon printing the first character, the cam 77 rocks the bail 56 counterclockwise, but the vibrator 29 is not raised because the lug 97 is arrested by the shoulder 96 of the lever 87. On the contrary, the lug 79 of the bail 56 is brought in front of the shoulder 81 and is locked by this latter in the position shown by broken lines in the FIG. 1. Therefore, the bail 56 is prevented from being restored clockwise and the ribbon feeding device rendered ineffective in the first, as well as in the following printing cycles, until the lever 93 will be returned to the position of FIG. 1.

What I claim is:

1. In a variable spacing typewriter having a cyclically operating mechanism, a set of types, a set of intermediate members associated with said types and individually movable from a rest position to an operated position to condition the associated type for printing, and a spacing control mechanism comprising a universal member controlled by said cyclically operating mechanism for sensing the intermediate member so moved, said universal member being arrested by the various intermediate members upon being moved through different extents for causing a letter spacing proportional to said extent, a carbon ribbon feeding device for feeding a carbon ribbon through a printing point, comprising in combination:

(a) a pair of friction rollers for feeding said ribbon in an advancing direction,

(b) a ratchet wheel connected to one of said rollers,

(c) a pair of parallel pawls cooperating with said ratchet wheel at two diametrically opposite sides thereof,

((1) a bar mounting said pair of parallel pawls,

(e) means operated by said cyclically operating mechanism for reciprocating said bar through a forward stroke and a return stroke,

(f) resilient means connecting said bar to a first one of said pair of parallel pawls for rotating said ratchet wheel a first increment during said forward stroke, the other pawl being effective to rotate said ratchet wheel a second increment during said return stroke,

(g) a removable stop element normally located on the path of the forward stroke of said first pawl,

(h) and a member connected to said universal member for removing said element from said path when said universal member has been moved at least through a predetermined one of said extents.

2. A ribbon feeding device according to claim 1, wherein said pawls are formed of a pair of slides at two opposite sides of said ratchet wheel, said bar being parallel to said ratchet wheel, said pair of slides being pivotable and axially shiftable on said bar, a pair of lugs being integral with said pair of slides and directed in opposite directions for cooperating with said ratchet wheel at two diametrically opposite sides thereof, said ribbon feeding device further comprising in combination:

(i) a spring urging said pair of slides axially toward each other,

(i) and a slot on one of said pair of slides and engaging said bar for enabling said first slide to be moved perpendicular to said bar.

3. In a variable spacing typewriter having a set of types, a set of intermediate members associated with said types and individually operable to condition the associated type for printing, and a spacing control mechanism cooperating with the so operated intermediate member for causing a letter spacing shorter than a predetermined spacing when the intermediate member associated with one of a first group of said types is operated and for causing a letter spacing at least equal to said predetermined spacing when the intermediate member associated With one of said second group of types is operated, a carbon ribbon feeding device for feeding a carbon ribbon through a printing point, comprising in combination:

(a) a pair of friction rollers for feeding said ribbon in an advancing direction,

(b) a ratchet wheel connected to one of said rollers,

(c) a pair of pawls cooperating with said ratchet wheel at two diametrically opposite sides thereof,

(d) a common member reciprocable concomitantly with the operation of each one of said intermediate members through a forward stroke and a return stroke during the printing of each one of said types,

(e) means connecting said common member with said pair of pawls to cause said common member to simultaneously reciprocate said pair of pawls,

(f) a spring comprised in said connecting means to cause said common member to yieldably operate a first one of said pair of pawls for rotating said ratchet wheel a first increment during said forward stroke, the other pawl of said pair of pawls being effective to rotate said ratchet wheel a second increment during said return stroke,

g) an element normally effective for preventing said first pawl from being operated by said common member through said spring,

(h) and a member operated by said spacing control mechanism for disabling said element when causing a letter spacing at least equal to said predetermined spacing.

References Cited UNITED STATES PATENTS 805,060 11/ 1905 Disbrow 197151 1,643,266 9/ 1927 Aichele l97-160 2,161,856 6/ 1939 Coxhead 197151 2,224,766 12/ 1940 Dodge 19784 2,425,967 8/1947 Toggenburger 197-151 2,609,077 9/ 1952 Schroder 197151 2,734,614 2/1956 Page 197151 2,972,402 2/ 1961 Howard 197165 3,026,987 3/ 1962 Gather 197165 X 3,151,722 10/ 1964 Salto 19717 3,288,262 11/ 1966 Salto 197-84 3,346,090 10/1967 Golf et al 197-151 X ERNEST T. WRIGHT, In, Primary Examiner.

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