US2707544A

US2707544A - Type bar actuating mechanism for typewriters or like machines

Info

Publication number: US2707544A
Application number: US307585A
Authority: US
Inventors: Edgar A Girouard
Original assignee: Royal Mcbee Corp
Current assignee: Royal Mcbee Corp
Priority date: 1952-09-03
Filing date: 1952-09-03
Publication date: 1955-05-03
Anticipated expiration: 1972-05-03

Description

May 3, '1955 E. A. GIROUARD TYPE BAR ACTUATING MECHANISM FOR TYPEWRITERS 0R LIKE MACHINES 2 Sheets-Sheet l Filed Sept. 5, ,1952

M. h Amig:

E. A. GlRouARD 2,707,544

TYPE BAR ACTUATING MECHANISI FOR TYPEWRITERS 0R LIKE IlAl'l-IINES May 3, 1955 2 Sheets-Sheet 2 Filed sept. s, 1952 musa www www? United States TYPE BAR ACTUATIN G MECHANISM FR TYPE- WRITERS 0R LIKE MACHINES Edgar A. Girouard, Hartford, Colm., assigner to Royal McBee Corporation, a corporation of New York Application September 3, 1952, Serial No. 307,585

18 Claims. (Cl. 1971'7) This invention relates to type bar actuating mechanism for typewriters or like machines, and more particularly to type bar operating mechanism having parts so structurally and functionally inter-related to each other and to case shifting mechanism as to adjust themselves automatically in response to operation of the case shifting mechanism for varying the printing force executed by a type bar according to whether it prints a character oi relatively large printing area or a character of relatively small printing area.

An object of the invention is to provide improved mechanism of the kind referred to.

Another object of the invention is to provide mechanism of the character stated in which positive driving effort is applied to the operating mechanism during a part only of the operating stroke, the final part of the type bar stroke being effected by the momentum of the parts, the arrangement being such that when the case shifting mechanism isV conditioned for the printing of the character of relatively large area the positive drive portion of the stroke will be relatively long and the momentum effected part of the stroke will be relatively short; whereas when the case shifting mechanism is conditioned for the printing of the character of relatively small area the positive drive portion of the stroke will be relatively short and the momentum effected portion of the stroke will be relatively long.

A further object of the invention is to provide mechanism of the class referred to in which the type bar operating mechanism is adapted to be actuated by power mechanism which, itself, may include an actuator driven positively during part of its operating stroke and driven by momentum for the remainder of its stroke.

Other objects of the invention will become apparent from a reading of the following description, the appended claims, and the accompanying drawings, in which:

, Figure l is a fragmentary view, partly in side elevation and partly in vertical section, fore and aft of a typewriter embodying the invention;

Figure 2 is a perspective view of an operating lever, drawn on an enlarged scale;

Figure 3 is a fragmentary sectional view on the line f z.

3 3 of Figure 1, drawn on an enlarged scale;

Figure 4 is a detail view, partly in section and partly schematic, showing different positions of a type bar and operating mechanism therefor during different phases of an operating stroke of the type bar when the machine is conditioned for typing lower case characters; and

Figure 5 is a view similar to Figure 4, but showing positions which the parts occupy during different phases of a typing stroke when the machine is conditioned for upper case typing.

The invention may be incorporated in typewriter or like machines of different constructions. The drawings show the invention as being embodied in a Royal electric typewriter many of the parts of which are of known construction and arrangement. The machine illustrated in- 2,767,544 Patented May 3, 1955 'ice formed with a groove for receiving anti-friction balls 2 supported on which is the upper track rail 3 of a carriage B. The rails 1 and 3 and the interposed balls 2 mount the carriage B for letter spacing and return travel on the frame A in the usual manner. The carriage is equipped with the usual cylinder or platen C.

Mounted for vertical shifting movements on the frame A is a type bar segment 4 provided with an arcuate pivot wire 5 serving pivotally to mount the usual complement of type bars, one of which is shown at 6. The type bar 6 is formed with the usual type bar head 6a having a lower case character 6b, such as a letter or numeral of relatively large printing area, and an upper case character 6c such as a punctuation mark, e. g., a period, of relatively small printing area. When the type bar is at rest in its normal position its head 6 is supported by an arcuate resilient cushion 7.

Normally, the type bar segment 4 is in the position shown in Figures 1 and 4 in which it is so related to the platen C that when the type bar 6 is moved to the printing position indicated in dotted lines in Figure l, the lower case character 6b will print on a work sheet positioned against the platen. In order to condition the machine for the typing or printing of upper case characters, the segment 4 is moved downwardly so that when the type bar 6 moves to its printing position the character 6c will print. The mechanism for moving the segment 4 downwardly to its upper case position may include links, one of which is shown at 8, pivoted at 9 to the segment and pivoted at 10 to a rock arm 11 on a rock shaft 12. The

-1 shaft may be rocked counterclockwise for moving the Lli) i printing character of relatively smaller area, and to the combination of such additional mechanism with parts previously described and other parts to be described later.

The type bar operating or driving mechanism shown as embodying the invention in a preferred form includes a; an operating lever 13 pivoted at 14 on a cross bar 15 secured to the main frame A. The top of the lever 13 is formed with a substantially vertically extending slot 16 through which extends a pivot part 17 on the front end of a link 1S the rear end of which is pivoted at 19 to :e5 an arm 20 on the type bar 6. A link 21 pivoted at 22 to the operating lever 13 extends rearwardly and is equipped with a spring 23 the rear end of which is xed to an anchorage (not shown) at the rear of the machine. The spring 23 and link 21 urge the lever 13 to its nonactuated or normal position shown in full lines in Figure 1.

Key operated or key controlled mechanism is provided for swinging the operating lever 13 forwardly, that is, counterclockwise as viewed in Figure 1, for pulling .l the link 18 and thereby swinging the type har 6 clockwise from its normal or at rest position to the printing position shown in dotted lines in Figure 1. In the form shown, the mechanism for actuating the lever 13 is power driven under the control of key mechanism similar to that disclosed in the patent to William H. Kupper, No. 2,567,945, issued September 18, 1951.

lt includes a driving element, which operates continuously, and controllable driving connections, which normally are inoperative, or ineffective, but which may be conditioned by the operator to effect operative driving connection cludes a frame A equipped with a lower track rail 1 between the continuously moving driving member L" and thc operating lever i3. The driver is constituted by a continuously rotating element, more particularly a toothed snatch roll or bar 24, which may be of known form, and which is adapted to be driven in the direction of the arrow x in Figure l by any suitable means, but preferably by an electric motor (not shown).

The means for transmitting drive from the driver 24 to the lever 13 includes an actuator 25 which extends fore and att of the typewriter and above the member 24. The actuator 25 is pivoted as at 25 to the lever 13, and has a forwardly extending part 27 projecting under an abutment or guide plate 28 mounted on a frame cross bar 29 to extend parallel to the snatch roll 2li. A spring 30, interposed between the front end of the actuator 2S and an anchor plate 3l, yieldably urges the actuator to rock clockwise, and thus normally maintains the actuator in the position shown in Figure l with its iront end part 27 bearing against the abutment of ,guide plate 28. Another abutment 32 is disposed below the abutment 23, and is slotted to receive and guide the lower extremity of the actuator part 27 for sliding movements.

ln order to apply a power impulse to the lever 13, the actuator 25 is operatively but indirectly connected to the driving member 24, the actuator itself never engaging the driving member. Mechanism for bringing about the operative connection of the actuator element 25 to the member 24, includes an interponent pawl or coupler 33, pivoted as at 34 on the actuator. A spring 35, anchored to the actuator 25 and connected to the pawl part 33, biases or urges the latter to rock clockwise so as to move its nose 36 into transient engagement with the snatch roll 24. Normally, the pawl is maintained out of engagement with the snatch roll by the restraining action of a control element or trigger 37 which is pivoted as at 322 on the actuator 25. in the normal position of the trigger, its rear end 39 engages a holding surface 40 on the pawl so as to prevent the spring 35 from rocking the pawl 33 into drive-transmitting engagement with the driving member 24. The pawl 33 is formed with an inclined resetter cam face 4l which is located just below thc holding surface 40, and which is acted upon by the trigger for rocking the pawl counterclockwise, and thus resettingI it in normal, inoperative position.

A key operated lever 42, pivoted at s3 on the cross bar 29, has an upward projection 44 disposed behind an arm 45 of a lever 46 pivoted at 47 on a frame cross bar 48. The lever 46 has another arm 49 on which a limber dog or lipper 50 is pivoted at 51. A spring 52 urges the limber dog 50 to rock clockwise to retain it yieldably in its normal position of rest against a limit stop 53. The dog can swing eounterclockwise from the position shown in Figure 1, but cannot move clockwise from this position. in the normal positions of the parts, the lower end of the lmber dog 50 overlies a contact ear 54 on the actuator 25.

In operation. when the key ft2 is depressed, the lever 46 is rocked clockwise so as to cause the ipper 50 to push the actuator 25 downwardly to an initial extent sucient to bring the trigger 37 into engagement with the abutment 32. This causes the trigger to be rocked clockwise about its pivot 38, so as to release the pawl 33, which is then moved by the spring 35 into engagement with the snatch roll 24. The snatch roll then drives the pawl 33 and actuator 25 as a unit so as to rock the lever i3 and operate the link i8 and type bar 6. When the pawl 33 is cast ofi from engagement with the snatch roll 24?. the spring 30 lifts the actuator 25 to bring the trigger 37 into engagement with the upper, trigger-resetting abutment 28. This causes the trigger' 37 to be rocked counterclockwise, so as to move its end 39 against the resetting cam face i1 of the pawl 33, thereby restoring the latter to its inactive position. The parts of the power mechanism will then be returned toward their normal positions by the spring 23. A compression spring 55 interposed between an arm 56 on the lever 46 and a seat S7 ou the cross bar 4S assists in returning the lever 46 l to its normal position. A contractile spring 58 connected between the key lever 42 and the lever arm 56 yieldably holds the key lever in its normal position against a cushion 59.

Means are provided for adjusting or varying the amount of driving impulse generated by the power mechanism. This variation or adjustment is effected by variably limiting the extent to which the actuator pawl nose 36 enters a tooth interspace on the snatch roll 24 under the urge of the spring 35 when the restraint of the trigger' 37 on the pawl 33 is discontinued. ln the form shown, the actuator 25 is provided with a downwardly extending stop element or finger 60 which is disposed in front of. and normally out of contact with a downwardly extending stop part, heel, or linger 6l on the pawl 33. When the pawl 33 is rocked clockwise by the spring 35 so as to move the pawl nose 35 into a snatch roll tooth interspace, the pawl stop 61 moves toward the actuator stop 60, which may be so positioned as to be engaged by the stop 6l to arrest rocking of the pawl 33 before the tooth 36 moves to the root of the snatch roll tooth interspace. By variably positioning one of the stops 6), 61, e. g., by bending the stop 6d towards or away from the stop 61, the extent to which the pawl tooth 36 enters the tooth interspace can be varied. Consequently, the angle through which the snatch roll rotates while in contact with the pawl, which determines the amount of driving of the pawl 33 and ractuator 25 by the snatch roll 24, can be varied. Any suitable means or construction may be provided for adjusting one of the stops 6i), 6l relatively to the other, but in the preferred construction the stop 60 is formed integrally with the actuator 25 so as to be bendable toward or away from the stop 6l.

In typewriters or like machines in which all or some of the instrumentalities to be operated, e. g., type bars, carriage return mechanism, tabulating mechanism, and escapement mechanism, are operated by power, it may be desirable to provide means for varying collectively the extent of driving of the several actuator pawls corresponding to the pawl 33 and associated with the other mechanisms referred to. This may be accomplished by providing a knock off bar 62 mounted on the main frame so as to extend under the front ends of all of the actuators corresponding to the actuator 33 shown in Figure l. Any suitable means (not shown) may be provided for adjustably tilting or otherwise variably positioning the knock oi bar 62 so that it will be engaged by the lower ends of the actuators to control the timing of disengagement of the associated actuator pawls from the snatch roll.

While it is possible to vary the movement imparted to the operating elements 1.3 either individually or collectively as explained above, uniform movement strokes are imparted to the elements 13 once the desired adjustment has been made. The positioning of the type bar segment 4 selectively in upper case and lower case positions does not affect this adjustment.

In order to adapt the mechanism to perform repeat typing operations, particularly when underscoring with dashes, or typing a line of dots, the machine may bc equipped with repeat typing mechanism of the kind disclosed and claimed in the copending application of William H. Kupper, Serial No. 187,587, tiled September 29, 1950, now Patent No. 2,620,056, dated December 2. 1952. A portion only of the repeat typing mechanism is shown as including a repeat key lever 63 pivoted at 64 on a frame mounted bracket 65 and connected at its rear end to a link shown only partially at 66. The link 66 connects the key lever 63 to repeat operation mechanism disclosed in detail in the aforementioned copending application Serial No. 187,587.

Operation When the machine is conditioned for lower case typing with the segment 4 in its upper position, the parts will be in the relative positions shown in Figures 1 and 4.

The relative dimensions and locations of the parts of the variable motion transmitting means are such that the adjustable pivot device 17 between the link 18 and the operating lever element 13 will be in the lower end of the slot 16, and the link 18 will be inclined rearwardly and upwardly from the pivot 17. Both pivots 17 and 19 will be below the pivot 5 and above the pivot 14. When/ the lever 13 rocks counterclockwise from its normal position indicated at a to the partial stroke position indicated at b, the shiftable pivot 17 will automatically be moved linearly into the upper end of the slot 16 and the motion transmitting link device 18 will be pulled forwardly to swing the type bar 6 from its normal position indicated at a to its partial stroke position b. Thereafter the pivot parts 17 will remain in the upper end of the slot 16 while the lever 13 moves to the position indicated at c, thereby swinging the type bar 6 to the position indicated at c. At about the time the lever 13 reaches the position c and the type bar reaches the position c', the pawl or interponent 33 is cast olf the snatch roll 24 so as no longer to be positively driven thereby. Consequently, the lever 13 and type bar 6 will complete their operating strokes by momentum of the parts, the lever 13 moving to the position indicated at a' and the type bar 6 moving to the position indicated at d', which is its printing position. During the movement of the lever 13 from its position indicated at b to its linal position indicated at rl, the pivot part 17 will be in the upper end of the slot 16, and thus will be at a maximum distance from the pivot 14 of the lever 13 so that the type bar will be driven rapidly.

When the machine is conditioned for upper case typing, the segment 4 will be below the position shown in Figure l and the parts will be in the relative positions shown in Figure 5. The pivots 17 and 19 will be below the pivot 5 and above the pivot 14, as is the case when the parts are conditioned for lower case typing; but the position of the pivotal connection 17 on the operating element 13 will be changed so as to be at the upper end of the slot 16 and above the pivot 19 instead of below it, as is the case when the parts are conditioned for lower case typing. The pivot 17 will have been moved to the upper endot' the slot 16 in response to lowering of the segment 4 and pivot 5, exerting a forward thrust through the link 18, causing the pivot 17 to move upwardly in the slot 16. When the lever 13 rocks counterclockwise during the initial part of its stroke from its normal position aa to the position bb, the pivot 17 is moved downwardly to the lower end of the slot 16 and the link 18 is pulled forwardly to rock the type bar from its rest position indicated at a'a' to the position indicated at bb. During the next part of the stroke of the lever 13 from its position bb to the position indicated at cc, the pivot 17 will remain in the bottom of the slot 16 and the link 18 will be pulled forwardly to swing the type bar from its position bb' to its next position cc. During the major part of the travel of the type bar from its initial position aa to its position cc, the pivot part 17 will be in the lower end of the slot 16 and relatively close to the pivot 14 of the lever 13, so that the type bar will be driven at less speed than when the parts are positioned and operated for lower case typing as described above with referenceto Figure 4. When the lever 13 has reached the position shown at cc in Figure 5 and the type bar has reached the corresponding position cc', the interponent or pawl 33 will be cast ot the snatch roll 24 so that the remainder of the stroke of the lever 13 and type bar 6 will be performed by momentum. The type bar 6 will travel from its position cc to its printing position rld' 'under the iniluence of the momentum of the parts only, and without positive drive transmission from the snatch'roll 24. This momentum will be sufficient to move the pivot 17 into the upper end of the slot 16 when the lever 13 is in the position shown at dd.

It `will be observed by a comparison of Figures 4 and 5v. that the angle through which the type bar 6 travels by momentum from its position c'c to its typing position dd, when the parts are conditioned for upper case typing, is considerably greater than the angle through which the type bar travels in passing by momentum from its position c to its printing position d shown in Figure 4, when the parts are conditioned for lower case typing. Therefore, the upper case character 6C of relatively small printing area will type with less force than the lower case character 6b of relatively large printing area, and the intensity or darkness of the printed characters will be substantially uniform, irrespective of which case is typed, and much more uniform than if the upper and lower case characters of dierent printing areas exterted equal printing forces.

The mechanism disclosed embodies the invention in a preferred form, but it is intended that the disclosure be illustrative rather than delinitive of the invention. The invention is defined in the appended claims.

I claim:

l. In a typewriter or like machine, a platen; a type bar having a lower case character and an upper case character, said characters being of different printing areas and being adapted selectively to print on a work sheet positioned against said platen; means mounting said type bar for printing movement relative to said platen; case shifting means for effecting relative shifting between said type bar mounting means and said platen for selecting which of said case characters is to print; and mechanism for operating said type bar to cause it to perform a printing stroke and including an actuator, an operating element, means driven by said actuator for imparting uniform movement strokes to said operating element irrespective of the relative positions of said type bar mounting means and said platen, and variable motion transmitting means operatively connecting said operating element to said type bar and being automatically adjustable in response to operation of said case shifting means for causing said type bar to print with a force when said upper case character prints which is diiferent from the force with which it prints when said lower case character prints.

2. In a typewriter or like machine, a platen; a type bar having a lower case character and an upper ease character, said characters being of different printing areas and being adapted selectively to print on a work sheet positioned against said platen; means mounting said type bar for printing movement relative to said platen; case shifting means for effecting relative shifting between said type bar mounting means and-said platen for selecting which of said case characters is to print; and mechanism for operating said type bar to cause it to perform a printing stroke and including an actuator, an operating element, means driven by said actuator for imparting uniform movement strokes to said operating element irrespective of the relative positions of said type bar mounting means and said platen, and variable motion transmitting means foroperatively connecting said operating element to said type bar to transmit positive driving effort from said operating elementA to said type bar during a rst portion only of the printing stroke of said type bar and for enabling the type bar to complete its typing stroke by momentum, said motion transmitting means comprising an adjustable device automatically adjustable in response to operation of said case shifting means for decreasing the positive drive portion of the type bar stroke and increasing the momentum effected portion of said stroke when a predetermined one of said characters prints.

V3. In a typewriter or like machine, aplaten; a type bar having a lower case character and an upper case character, said characters being of different printing areas and being adapted selectively to print on a work sheet positioned against said platen; means mounting said type bar for printing movement relative to said platen; case shifting means for effecting relative shifting between said type' bar mounting means and said platen for selecting which of said case characters is to print; and mechanism for operating said type bar to cause it to perform a printing strol-re and including an actuator, a lever, means driven by said actuator for imparting uniform movement strokes to said lever irrespective of the relative positions of said type bar mounting means and said platen, and variable motion transmitting means for operatively connecting said lever to said type bar to transmit positive driving effort from said lever to said type bar during a rst portion only of the printing stroke of said type bar and for enabling the type bar to complete its typing stroke by momentum, said motion transmitting means comprising a motion transmitting device, and a pivotal connection between said lever and said motion transmitting device automatically adjustable in response to operation of said case shifting means for varying the position of said pivotal connection on said lever so as to decrease the positive drive portion of the type bar stroke and increase the momentum effected portion of said stroke when a predetermined one of said characters prints.

4. in a typewriter or like machine, a platen; a type bar having a lower case character and an upper case character, said characters being of different printing areas and being adapted selectively to print on a work sheet positioned against said platen; means mounting said type bar for printing movement relative to said platen; case shifting means for effecting relative shifting between said type bar mounting means and said platen for selecting which of said case characters is to print; and mechanism for operating said type bar to cause it to perform a printing stroke and including an actuator, and variable motion transmitting means for operatively connecting said actuator to said type bar to transmit positive driving effort from said actuator to said type bar during a rst portion only of the printing stroke of said type bar and for enabling the type bar to complete its typing stroke by momentum, said motion transmitting means comprising an element operable by said actuator, a link connected to said type bar, and a shiftable pivot device connecting said link to said element and being automatically adjustable in response to operation of said case shifting means for decreasing the positive drive portion of the type bar stroke and increasing the momentum effected portion of said stroke when a predetermined one of said characters prints.

5. In a typewriter or like machine, a platen; a type bar having a lower case character' and an upper case character, said characters being of different printing areas and being adapted selectively to print on a work sheet positioned against said platen; means mounting said type bar for printing movement relative to said platen; case shifting means for effecting relative shifting between said type bar mounting means and said platen for selecting which of said case characters is to print; and mechanism for operating said type bur to cause it to perform a printing stroke and including an actuator, and variable motion transmitting means ior operatively connecting said actuator to said type bar to transmit positive driving effort from said actuator to said type bar during a rst portion only of the printing stroke of said type bar and for enabling the type bar to complete its typing stroke by momentum, said motion transmitting means comprising a pivotcd lever operable by said actuator and having a slot, a link connected to said type bar, and a pivot part on said link mounted in said slot for movements relatively to said lever both pivotally and linearly along said slot, said pivot part being automatically movable along said slot in response to operation of said case shifting means for dccreasing the positive drive portion of the type bar stroke and increasing the momentum effected portion of said stroke when a predetermined one of said characters prints.

6. In a typewriter or like machine, a platen; a type bar having a lower case character and an upper case character, said characters being of different printing areas and being adapted selectively to print on a work sheet positioned against said platen; means mounting said type bar for printing movement relative to said` platen; case shiftiii.

ing means for cfecting relative shifting between said type bar mounting means and said platen for selecting which of said case characters is to print; and mechanism for operating said type bar to cause it to perform a printing stroke and including an actuator, an operating element, means driven by said actuator for imparting uniform movement strokes to said operating clement irrespective of the relative positions of said type bar mounting means and said platen, and variable motion transmitting means operatively connecting said operating element to said type bar and including a device automatically adjustable in response to the operation of said case shifting means for so varying `the motion transmitting characteristics of said motion transmitting means as to cause the smaller area one of said characters to print with less force than that '.'ith which the larger area one of said characters print.

7. ln a typewriter or like machine, a platen; a type bar having a lower case character and an upper case character, said characters being of different printing areas and being adapted selectively to print on a work sheet positioned against said platen; means mounting said type bar for printing movement relative to said platen; case shifting means for effecting relative shifting between said type bar mounting means and said platen for selecting which of said case characters is to print; and mechanism for operating said type bar to cause it to perform a printing stroke and including an actuator, an operating element, means driven by said actuator for imparting uniform movement strokes to said operating element irrespective of the relative positions of said type bar mounting means and said platen, and variable motion transmitting means operatively connecting said operating element to said type bar and including a shiftable pivot device automatically shiftable in response to the operation of said case shifting means for so varying the motion transmitting characteristics of said motion transmitting means as to cause the smaller area one of said characters to print with less force` than that with which the larger area one of said characters prints.

8. in a typewriter or like machine, a platen; a type bar having a lower case character and an upper case character, said characters being of different printing areas and being adapted selectively to print on a work sheet positioned against said platen; means mounting said type bar for printing movement relative to said platen; case shifting means for effecting relative shifting between said type bar mounting means and said platen for selecting which of said case characters is to print; and mechanism for operating said type bar to cause it to perform a printing stroke and including an actuator, and variable motion transmitting means operatively connecting said actuator to said type bar and including a pivotcd lever operable by said actuator and having a slot, a link connected to said type bar, and a pivot part on said link mounted in said slot for movements relatively to said lever both pivotally and linearly along said slot, said pivot part being automatically movable along said slot in response to the operation of said case shifting means for so varying the motion transmitting characteristics of said motion transmitting means as to cause the smaller arca one of said characters to print with less force than that with which the larger area one of said characters prints.

9. In a typewriter or like machine, a platen; a type bar having a lower case character of relatively large printing arca and an upper case character of relatively small printing area adapted selectivelyA to print on a work sheet positioned against said platen; a support; a rst pivot mounting said type bar on said support for printing movement relative to said platen; case shifting means for shifting said support downwardly from lower case position to upper case position; an operating lever; a second pivot below and in front of said first pivot mounting said lever to swing forwardly from a normal non-actuated position; a substantially vertically extending slot in the top of said lever; a downwardly extending arm on said type bar; a link; a third pivot connecting the rear end of said link to said arm below said first pivot and above said second pivot; and a fourth pivot on the front end of said link below said rst pivot and above said second pivot and extending into and being slidable in said slot, the relative dimensions and locations of the parts being such that when said support is in its lower case position and said lever is in its normal non-actuated position said fourth pivot is in the lower end of said slot whereas when said support is in its upper case position and said lever is in its normal non-actuated position said fourth pivot is in the upper end of said slot.

10. In a typewriter or like machine, a platen; a type bar having a lower case character of relatively large printing area and an upper case character of relatively small printing area adapted selectively to print on a work sheet positioned against said platen; a support; a rst pivot mounting said type bar on said support for printing movement relative to said platen; case shifting means for shifting said support downwardly from lower case position to upper case position; an operating lever; a second pivot below and in front of said first pivot mounting said lever to swing forwardly from a normal non-actuated position; a substantially vertically extending slot in the top of said lever; a downwardly extending arm on said type bar; a link; a third pivot connecting the rear end of said link to said arm below said first pivot and above said second pivot; and a fourth pivot on the front end of said link below said rst pivot and above said second pivot and extending into and being slidable in said slot, the relative f dimensions and locations of the parts being such that when said support is in its lower case position and said lever is in its normal non-actuated position said fourth pivot is in the lower end of said slot and below said third pivot whereas when said support is in its upper case position and said lever is in its normal non-actuated position said fourth pivot is in the upper end of said slot and above said third pivot.

l1. In a typewriter or like machine, a platen; a type bar having a lower case character of relatively large printing area and an upper case character of relatively small printing area adapted selectively to print on a work sheet positioned against said platen; a support; a first pivot mounting said type bar on said support for printing movement relative to said platen; case shifting means for shifting said support downwardly from lower case position to upper case position; an operating lever; a second pivot below and in front of said flrst pivot mounting said lever to swing forwardly from a normal non-actuated position; a substantially vertically extending slot in the top of said lever; a downwardly extending arm on said type bar; a link; a third pivot connecting the rear end of said link to said arm below said rst pivot and above said second pivot; and a fourth pivot on the front end of said link below said lirst pivot and above said second i pivot and extending into and being slidable in saidslot, the relative dimensions and locations of the parts being such that when said support is in its lower case position and said lever is in its normal non-actuated position said fourth pivot is in the lower end of said slot and said link is inclined rearwardly and upwardly from said fourth pivot to said third pivot, whereby when said support is moved downwardly to upper case position said fourth pivot will automatically shift to the upper end of said slot.

12. In a typewriter or like machine, a platen; a type bar having a lower case character of relatively large printing area and an upper case character of relatively small printing area adapted selectively to print on a work sheet positioned against said platen; a support; a iirst pivot mounting said type bar on said support for printing movement relative to said platen; case shifting means for shifting said support downwardly from lower case position to upper case position; an operating lever; a second pivot below and in front of said rst pivot mounting said lever to swing forwardly from a normal nonactuated position; a substantially vertically extending slot in the top of said lever; a downwardly extending arm on said type bar; a link; a third pivot connecting the rear end of said link to said arm below said irst pivot and above said second pivot; and a fourth pivot on the front end of said link below said first pivot and above said second pivot and extending into and being slidable in said slot, the relative dimensions and locations of the parts being such that when said support is in its lower case position and said lever is in an actuated position in which it is swung forwardly from its normal position said fourth pivot will be in the upper end of said slot and hence relatively far from said second pivot, whereas when said support is in its upper case position and said lever is in its said actuated position said fourth pivot will be in the lower end lof said slot and hence relatively close to said second pivot.

13. Construction as set forth in claim 1 including a power driven member; and key controlled means for operatively connecting said actuator to said member to be driven thereby to operate said type bar.

14. Construction as set forth in claim 3 including a power driven member; and key controlled means for operatively connecting said actuator to said member to be driven thereby to operate said type bar.

15. Construction as set forth in claim 5 including a power driven member; and key controlled means for operatively connecting said actuator to said member to be driven thereby to operate said type bar.

16. Construction as set forth in claim 8 including a power driven member; and key controlled means for operatively connecting said actuator to said member to be driven thereby to operate said type bar.

17. Construction as set forth in claim 10 including a power driven member; and key controlled means for operatively connecting said operating lever to said member to be driven thereby to operate said type bar.

18. Construction as set forth in claim 12 including a power driven member; and key controlled means for operatively connecting said operating lever to said member to be driven thereby to operate said type bar.

References Cited in the tile of this patent UNITED STATES PATENTS Pitman Mar. 14, 1944