US1370237A - Typewriting-machine - Google Patents

Description

B. C. STlCKNEY.

TYPEWRITING MACHINE.

APPLICATION FILED SEPT. 21, 1917.

Patented Mar. 1, 1921,

l V/ f/vesses UNITED STATES PATENT omen.-

BURNHAM C. STICKNEY, OF ELIZABETH, NEW JERSEY, ASSIGL TOR TO UNDERWOOD TYPEWRITER COMPANY, OF NEW YORK, N. Y., A CORPORATION OF DELAWARE.

'ryrnwnrrmamaonrnn Specification of Letters Patent.

Patented Mar. 1, 1921.

Application filed September 21, 1917. Serial No. 192,469.

T 0 all whom it may concern.

Be it known that I, BURNHAM O. STICK- NEY, a citizen of the United States, residing in Elizabeth, in the county of Union and State of New Jersey, have invented certain new and useful Improvements in Typewriting-Machines, of which the following is a specification.

This invention relates to a universal linespacer f6;- the platen of a typewriting machine, to be capable .of fine or universal regulation of the spacing of vthe typewritten lines.

Upon a drum I wind a flexible clutch band, preferably two or more times, to secure a firm grip thereon by reason of the extent of the winding. The drum may be connected to the platen, although the invention is capable of reversals of parts in various ways.

The usual line-spacing lever is connected to tighten the band upon the drum, and then by means of the band to turn the drum and platen, to an extent whichis universally or minutely variable. At the line spacing op eration, the line-space lever acts upon one end of the band to tend to draw it around the drum, while a spring opposes the tendency of the other end of the band to yield to the pull of the band. Hence, the band, by reason of its self-binding tendency, be-

comes suiiiciently tight upon the drum to enable the band to be employed for rotating the drum and platen, and to overcome the inertia of these parts without slipping in starting their rotation.

The line-spacing mechanism and platen are arrested by means of a stop, which engages and positively arrests the free or dragging end of the band, so that the shock of arresting the hand of the operative is sustained by the entire band, which thereby is caused to bind itself even more firmly on the drum, to counteract the tendency of the platen to overthrow at this time, due to its momentum. In other words, the grip or control of the band or driving clutch is momentarily increased as the platen is arrested.

The stop which arrests the line-spacing mechanism and the platen, is preferably fixed, to secure effectiveness, and the regulation of the extent of line-space movement is preferably secured by means of a linespace regulator which shifts the entire clutch mechanism relatively to said fixed stop, to any predetermined extent within the maximum range of adjustment provided. Upon release of the line-space handle, it is returned to normal position by means of a spring, and the clutch band is permitted special brake is provided, which holds the drumand platen during the early part of the return stroke of the line-space handle or lever. -Upon the conclusion of the return stroke of the line-space lever, said brake is released, as 1t is no longer needed, since, by this time, the clutching band has relaxed and released the drum.

The l1ne-space lever preferably has a uniform throw and picks up the clutch mechanism early or late in its stroke according to the position of adjustment of the linespace regulator. l I

S1nce the line-space lever and a slide operated thereby have uniform strokes regardless of the regulation of the line-spacing throw, these parts may be used to throw a brake into and out of use, the brake being thrown into use at the conclusion of the drive, and thrown out of use at the conclu- S1011 of the return stroke of these parts; this effect being uniform for all line-space movements' secured by the adjustment of the regulating devices.

The spring, hereinbefore mentioned, for opposing the pull on the clutch band, also serves to restore the free or dragging end of the clutch band to normal position. This spring may be of light tension so as not to have an undue tendency to bind the band and retract the drum and platen during the retraction of the line-space lever. Moreover, this spring may itself constantly operate a separate brake, which engages the drum to hold the platen stationary during the writing of the line, as well as to aid in preventing overthrow of the platen at the conclusion of the line-space throw. Provision is made for adjusting the pressure of this separate brake, so that it may be relatively strong while the pull of the spring upon the dragging end of the clutch band may be relatively light.

- sition.

Other features and advantages will here inafter appear.

In the accompanying drawings,

Figure 1 is a side elevation, showing my invention as applied to an Underwood typewriting machine.

Fig. 2 is a front elevation of the same. Fig. 3 is a perspective view of the parts shown in, Fig. 1.. v

Fig. 4 is a side elevation, showing some of the parts shown in Fig. 1, in operated po- 7 Fig. 5 is a perspective View, showing a modified form of the driving band shown in Fig. 3. I

Fig. 6 is.a front detail view of another Suitable form'of. driving band, which may be used when a very compact arrangement is desired. 7

In an Underwood typewriting machine, types 9 strike upwardly and rearwardly against a platen 10, mountedon axle 11, rotatably mounted in a left-hand end plate 12 and a right-hand end plate, not shown. For rotating the platen line by line, in the course -of typewriting, a line-space handle 13, provided with a finger-piece 14, is pivotally mounted on the frame or carriage of the machine at 15, and is provided with an arm 16 to drive a slide 17 rearwardly. The slide the form of a flexible chainIor band 21 which is wrapped more than once (preferably more than twice) around a friction drum 22 secured to'the platen axle 11, and forming a line-space wheel. This band or chain 21 is drawn tightly around the friction drum 22 by means of an arm 23 pivotally mounted upon the platen axle 11. The leading and 24 of the band is connected to the arm or lever 23 by means of a pin 25. The band-carrying arm 23 extends .up into the path of an operating pin 26 secured to the line-space slide 17 The other or dragging end 27 ofthe band 21 is supported upon a pin 28, on an arm 29 pivotally mounted upon the platen axle 11.

WVhen the line-space slide 17 is operated by the arm 16 of the line-space handle 13, the pin 26 on said slide engages and moves the arm 23. The first movement of the arm 23 causes the band 21 to be drawn tightly to the surface of the drum 22, owing to the self-binding character of the flexible band due to its prolonged winding around the drum. To favor this tightening of the band, an arm 30, formed upon the arm 29, is provided with a spring 31, forming a drag, which retards or tends to hold said draggingend of the band against movethe clutch band 21 and on the brake 32 may be separately adjusted by adjusting the ends of the spring 31 along the lever arm 30 and the brake lever 32, as indicated by the series of holes in these-levers.

After theband is clutched to the drum, the continued movement of the line-space slide 17 causes theplaten to rotate against the resistance of the brake 32 and of the spring 31, which, through the lever arms 29 and 30,- is connected to the dragging end of said band.

The band 21 may be in the form of a flexible spring metal strip, or may be a chain of metal links; or it may be of woven metal tape, as shown in Fig. 5. The drum 22 may preferably be of fiber or other suitable friction material, or it may be made of a softer metal than the band. If it is desired to have a metal ,drum, then the band may be made of fiber; or fiber links may be assembled in a chain; or a band of material softer. than the metal drum may be used. The tape of woven wire may be softer than the drum. If an extremely compact arrangement is desired, a thin chain, such as shown in Fig. 6, may be used.

By Winding the band several times about the drum, a very powerful gripping and binding, winch-like action is obtained, since the band is self-binding, and a light spring. 31 may hold the free end against move-- ment, while the band is being tautened upon the drum. A great deal of-contacting surface can be secured between the driving mechanism and the drum, Without materially increasing the Weight-of the mechanism.

At the conclusion of the drive-stroke, the

arm 29, carrying the dragging end of the band, is arrested by means of'a stop fixed to the end plate 12. When this arm 29 strikes said stop 35, the momentum of the driving parts is utilized fully to arrest the platen, because such momentum tends to cause the leadin end of the band to carry still farther, ut this (the dragging end of the band being engaged by a fixed and positive stop), can only tend to cause the band more firmly to grip the drum 22. Also, the momentum of the platen itself tends to tighten the clutch band into firmer gripping relation on the drum. Hence the by the operator, the slide 17 is returned to normal position by its spring 18. This causes the pin 26 on the slide to release the driving arm 23, which may, if desired, be retracted by a spring 36 (Fig. 1) connected to an arm 37 formed upon said arm 23. The spring 31 at this time causes the arm 29, carrying the dragging end of the band, to return to normal position, drawing the clutch-band idly back around the drum,

which is now stationary. The spring 36 renders the band somewhat slack, so that it will the better ride idly over the drum.

The constant brake 32 tends to hold the drum and platen at this time. As an aid,

7 however, in holding thedrum. and platen against movement when the band is returning, an auxiliary device may be provided, comprising a brake 38, havlng a shoe 39, and pivotally mounted upon a stub shaft 40 secured to the side plate 12. This brake lever is provided with an upstanding arm 41, normally located in the path of a pin 42 at the forward part of the line-space slide 17. When the latter approaches'the limit of its driving movement, the pin 42 moves the arm 41 and causes the brakeshoe 39 to be moved toward the drum. As.

until the clutch-band 21 has returned to' normal position, the brake being held during all this time by the notch 46 and the spring 45. As the returning slide 17 approaches its normal position, a pin 47 on said slide engages the arm 41, and restores the brake lever 38 to normal ineffective position, in which it is held by the detent notch 44 in sprin 45.

It is also noted that since this brake engages the drum before the drive-stroke of the line-space mechanism is completed, it aids in preventing overthrow of the platen, as also does the brake 32.

To regulate the extent of line-spacing movement a line-space regulator is provided, by which the entire clutch mechanism may be adjusted. The line-space handle and the line-space slide are preferably moved uniformly, irrespective of the. extent of movement which the platen receives.

A control plate 48, mounted conveniently on platen axle 11, is provided with-gear teeth 49, meshing with a worm 50 on a shaft 51 mounted in a bracket 52, secured to the side frame 12. A suitable fingerpiece 53 is connected to the shaft 51. A star-wheel 54 is also secured to the shaft 51 and coiiperates with a spring 55 to hold the shaft 51 against accidental rotation. When it is desired to regulate the movement, the finger-piece 53 is rotated to move the control plate 48 in either a clockwise or a counterclockwise direction, as seen in Fig.1,

until an indicator 56 is positioned opposite the proper indication on a scale 57 carried by the bracket 52. This scale 57 may be divided into five divisions, each of which indicates the usual line-space distances, and each of these divisions is divided into five sub-divisions. This scale and indicator aid the operator in locating the control plate 48 in position. The line-space distance may be minutely'varied.

The plate 48 controls the clutch mechanism through the medium of two pins 58 and 59, secured thereto. The pin 58 is arranged to be engaged by and limit the return movement of the arm 29 carrying the dragging end of the band, while the pin 59 1s arranged to engage and limit the movement of the arm 37, formed integral with the arm 23 which carries the leading end of the band 21. It will be seen, therefore, that the pin 58 andthe pin 59 limit the forward movement of the bandagainst the tension of the spring 31. Any adjustment of the controller plate48 will varythe normal resting position of the clutch mechanism. If the plate is moved clockwise, as seen in Fig. 1, the amount of movement given to the platen at the next line-space strokewill be increased. This movement of the clutch mechanism, independently of the slidev 17, is possible, because of the position of the pin 26 which. operates the arm 23'of the clutch mechanism. This pin 26, in normal position, permits the free movement of the arm 23 of the clutch mechanism within the limit of the mechanism.

Variations maybe resorted to .within the scope of the invention, and portions of the im rovements may be used without others. aving thus described my invention, I claim: 4

1. In a typewriting machine, the combination with a revoluble platen, of a linespace drum, an axle on which the platen and drum are mounted and line-space mechanism for the platen comprising a line-space nation with a platen, of a line-space wheel cause the band to more firmly-grip the line-- space wheel, said means being arranged to so increasethe binding action of the band upon the linerspace wheel at the end of the line-space stroke, that excessive movement,

of the platen is prevented.

3. In a typewriting machine, the combination with a platen, of a line-space wheel connected to said platen, a line-space handle, a frictional driving band wound several times about the line-space wheel and normally in a slack condition thereon, means for causing the frictional driving band to bind to the line-space wheel and then move said linespace wheel a predetermined distance, means adapted to arrest the driving band and simultaneously cause the band to more firmly grip the line-space wheel, said means i.

being arranged so as to so increase the binding action of the band upon the line-space wheel at the end of the line-space stroke, that excessive movement of the platen is prevented, means for returning the driving band to normal osition and a brake device normally free Ei'om said line-space wheel but moved into engagement with said line-o space wheel at the end of the line-space stroke, to hold said wheel and therefore the platen against movement while the driving band is being slackened and returned to normal osition. 7

4. n a typewriting machine, the combination with a revoluble platen, of a linespace drum, an axle on which the platen and drum are mounted, and line-space mechanism for the platen comprising a line-space handle, a band wound several times about the line-space drum and normally in a slack condition thereon, means arranged to first draw theband tightly about the drum and then rotate the drum a predetermined amount, and means for returning the band to normal position after the line-space operation, comprising a spring connected to each end of said band, said springs being so arranged as to cause the band to first become slackened and then be moved to normal position.

5. In a typewriting machine, the combination with a revoluble platen, of a linespace drum, an axle on which the platen and drum are mounted, line-space mechanism for the platen comprising -a line-space handle, a band wound several times about the line-space drum, an 1 arm pivotally mounted on said platen axle to which the leading end of sald band is connected, another arm on said platen axle to which the draggingend of the band .is connected, means operated by the line-space handle to operate the first-mentioned arm to cause said arm to first draw the band tightly about the drum and then rotate the drum, means for returning the band to normal position after the operation of the line-space handle comprising a spring connected to the arm which is connected to the dragging end of the band, and a spring connected to the leading end-of the band to cause the band to be returned in a slackened condition.

6. In a typewriting machine, the combination with a revoluble platen, of a linespace drum, an axle on which the platen and drum are mounted, line-space mechanism for the platen comprising a linespace handle, a band wound several times about the line-space drum, an arm pivotally mounted on said platen axle to which the leading end of said band is connected, an

other arm on said platen axle to which the dragging end of the band is connected, means operated by the line-space handle to operate the first-mentioned arm to cause said arm to first draw the band tightly about the drum and then rotate the drum, means for returning the band to normal position after the operation of the line-space handle comprising a spring connected to the arm which is connected to the dragging end of the band, a spring connected to the leading "end of the band to cause the band to be returned in a slackened condition, a normally ineffective brake for the platen, and means for automatically rendering the brake effective to hold the platen while the band is returned around the platen.

7 In a typewriting machine, the combination with arevoluble platen, of line-space mechanism for rotating said platen, said line-space mechanism comprising a drum connected to the platen, a frictional driving band wound more than once about said drum to cause the band to be self-gripping on the drum, driving means for drawing on the leading end of the band to cause the band to grip the drum and impart line-spacing movement thereto, a brake device for holding said platen against turning until said band firmly grips the drum, a stop for arresting the dragging end of the band in the line-spacing movement so as to cause the band more firmly to grip the drum, and asecond brake device normally ineffective but made effective by said driving means at the end of the line-spacing operation to hold the platen against returning while the band is returned and released from the drum.

8. In a typewriting machine, the combination of a revoluble platen and a reciprocating frictionally driving line-space mechanism for said platen comprising a reciprocating slide operated by a line-space handle, a drum, a driving band wound more than once around said drum, arms to which the ends of the driving band are connected, and a lost-motion connection between the reciprocating slide and one of said arms.

9. The combination of a revoluble platen,

a drum, a flexible band wound around the drum sufliciently to be self-tightening thereon, a driver connected to one end-of the band causing saidband to drive the platen, a returning spring connected with the dragging end of the band, and adapted to drag on the band sufliciently during the effective stroke of the driver to render the band selfbinding, a separate returning spring for said driver, means controlled by said driver for detaining the platen during the return movement of the band, and means for thereafter automatically releasing said detaining means.

10. The combination with a revoluble platen having a drum, of a flexible band wound more than once around the drum sufficiently to render the band self-binding upon the drum, a manually operable driver, means connecting said driver to the leading end of said band to rotate the platen thereby, a lever connected to the dragging end of said-band, a returning spring for said lever adapted to drag on the band sufficiently to render it self-binding at the actuation of the driver, and relatively adjustable stops to regulate the throw of said lever, thereby determining the extent of line-,

spacing movement of the platen eflected by said band, a fixed stop being provided for limiting the return stroke of said driver; said driver being constructed to operate during the last part of its driving stroke to drive the band and platen, and the length of stroke of said driver being sufficient to accommodate the entire range of adjustment of said regulatable stop lever.

11. The combination of a revoluble platen, a drum, a flexible band wound around the drum snfliciently to be self-tightening thereon, a driver connected to-one end of the band causing said band to drive the platen, a platen brake to constantly oppose rotation of the platen, and a spring acting between the brake and the dragging end of the band to operate the brake and to return the band around the drum.

12. The combination of a revoluble platen, a drum, a flexible band wound around the drum sufliciently to be self-tightening thereon, a driver connected to one end of the band causing said band to drive the platen, a platen brake to constantly oppose rotation =the binding effect of the band upon the of the platen, a spring acting between the platen rake and the dragging end of the and to operate the brake and to return the band around the drum, a second brake normally ineffective upon said platen, and means controlled by said driver for bringing the second brake into use at the conclusion of the driving stroke of said driver,

and for moving said second brake out of use turning spring connected with the dragging end of the band, and a platen brake connected with said spring to constantly oppose rotation of the platen, means being provided for regulating the pressure of said brake eflected by said spring.

14. The combination with a revoluble platen having an axle, of a drum, a flexible band wound around said drum, an arm pivoted upon said axle and connected to the leading end of said band, a manually operable driver for said arm, a second arm upon said axle connected to the dragging end of said band, and a returning spring connected to said second arm and adapted to drag on the arm sufficiently to render the band selfbinding on the drum at the actuation of the driver.

15. The combination with a revoluble platen having march, of a drum, a flexible band wound around said drum, an arm pivoted upon said axle and connected to the leading end of said band, a manually operable driver for saidarm, a second arm upon said axle connected to the dragging end of said band, a returning spring connected to said second arm, said driver including a lever, and a part operated by said lever and having means to engage the first-mentioned arm.

16. The combination with a revoluble "platen having an axle, of a drum, a flexible band wound around said drum, an arm pivoted upon said axle and connected to the leading end of said band, a manually operable driver for said arm, a second arm upon said axle connected to the dragging end of said band, a returning spring connected to said second arm, and means for regulating the stroke of the second arm.

17. The combination with a revoluble platen having a drum, of a flexible band wound around the drum to be self-tightening thereon, a driver connected to the leading'end of said band to tighten it upon the drum and thereby drive the platen, means for cotiperating with the other end of the band to arrest the same and thereby cooperate with the band and driver to increase drum by reason of the sudden arrest of the driving members, and means for draggmg the driver, a spring to return the driver,

on said other end sufliciently to render the band self-binding at the actuation of the driver.

18. The combinationof a revoluble platen having a drum, a flexible band wound more than once around the drum to be self tightening thereon, a manually operable driver, a lever connected to the leading end of said band to pull the same and operableby said driver during the last part of the stroke of and a-spring to return the lever.

19. The combination of a revoluble platen having a drum, a flexible band wound more than once around the drum to be self-tightening thereon, a manually operable driver, a lever connected to the leading end of said band to pull the same and operable by said driver during the last part of the stroke of the driver, a spring to return the driver, a spring to return the lever, and a s ring connected to the dragging portion 0 the band to return the same. i g

20. The combination with a revoluble platen and a drum, of a flexible band wound more than once around the drum to be selftightening thereon, means connected to the leading end of the band to drive the platen thereby, means connected to the leading end of the band to slacken the band to facilitate its returning around the stationary drum, a stop for the platen cooperative with the dragging end of the band to increase the grip of the band on the drum in stopping the platen, means connected to the dragging portion of the band to retard. the band to cause it to grip the drum for driving the platen and tending to return the band around the drum, a brake for said platen, and means for automatically rendering said brake efi'ective during the return of the flexible band around the drum; said brake be ing normally ineffective. p v

21. The combination of a revoluble platen, a friction device connected to said platen for driving the same, a driver for said friction device, a stop for arresting said driver, a normally ineffective brake for said platen, and means independent of said stop to enable said driver to bring said brake into action at the conclusion of the driving stroke of said driver.

22. The combination of a revoluble platen a friction device connected to said platen for driving the same, a driver forsaid friction device, a stop for arrestingsaid driver, a normally ineffective brake for said platen, means independent of saidstop to enable said driver to bring said brake into action at the conclusion of the driving stroke of said driver, and means controlled by said driver on its return stroke for releasing said brake. a

23. The combination ofa revoluble platen having a drum, a flexible band wound more than once around said drum to be self-tightening thereon, a driver, means connected to said driver to pull the leading end of said band, a stop to cooperate with the dragging end of'said band to arrest the 'band and driver and thereby momentarily increase the bite of the band upon the drum, and a normally ineffective brake for said platen controlled by said driver to be rendered effective, upon the platen at the conclusion of the driving stroke of said driver.

24. The combination of a revoluble platen having a drum, a flexible band wound more than once around said drum to be self-tightening thereon, a driver, means connected to said driver to pull the leading end of said band, a stop to cooperate with the dragging end of said band to arrest the band and driver and thereby momentarily increase the bite of the band upon the drum, a normally ineifective brake for said platen controlled by said driver to be rendered efi'ective upon the platen at the conclusion of the driving stroke of said driver, and means controlled by said driver upon its return stroke to release said brake.

25. The combination with a revoluble platen, of a reciprocatory driver having a uniform stroke, and a friction device where by said driver rotates said platen, means being provided for effecting minute regulation of the length of stroke of said friction device while the stroke of the driver remains uniform, such'means including a lost-motion operating connection between the driver and the friction device.

26. 'In a typewriting machine, the combination with a revoluble platen, of a linespacing mechanism comprising a drum connected to the plate-Ina band wound several times around the drum, a driving handle for drawing upon the leading end of the band to tighten the band on the drum and impart line-spacingmovement to the platen, means connected to the dragging end of the band to retardthe band and cause it to tighten on and grip the drum at the driving stroke of the handle and to tend to return the band around the drum to normal position while the drum is stationary at the return stroke of the handle, and means for effecting fine variations in the line-spacing movement imparted to the platen at the drivin stroke of the handle.

27. n a typewriting machine, the combination with a revoluble platen, of a linespacing mechanism comprising a drum connected to the platen, a band wound several times around the drum, a driving handle for drawing upon the leading end of the band to tighten the band on the drum and impart line-spacing movement to the platen,

tions in the line-spacing movement imparted to the platen at the driving stroke of the handle.

28. In a typewriting machine, the combination with a revoluble platen, of a linespacing mechanism comprising a drum connected to the platen, a band wound several times around the drum, a driving handle for drawing upon the leading end of the band to tighten the band on the drum and impart line-spacing movement to the platen, means connected to the dragging end of the 'band to retard the band and cause it to tighten on and grip the drum at the driving stroke of the handle and to tend to return the band around the drum to normal position while the drum is stationary at the return stroke of the handle, means forholding the drum and platen stationary while the band is being tightened on the drum, and means for effecting fine variations in the line-spacing movement imparted to the platen at the driving stroke of the handle.

29. In a typewriting machine, the combination with a revoluble platen, of a linespacing mechanism comprising a drum connected to the platen, a band wound several times around the drum, a driving handle for drawing upon the leading end of the band to tighten the band on the drum and impart line-spacing movement to the platen, means connected to the dragging end of the band to retard the band and cause it to tighten on and grip the drum at the driving stroke of the handle and to tend to return the band around the drum to normal position while the drum is stationary at the return stroke of the handle, means for holding the drum and platen stationary while the band is being returned around the drum, and means for efi'ecting fine variations in the line-spacing movemenuimparted to the platen at the driving strokepf the handle.

30. In a typewriting machine, the combination with a revoluble platen, of a linespacing mechanism comprising a drum connected to the platen, a band wound several times around the drum, a driving handle for drawing upon the leading end of the band to tighten the band on the drum and impart line-spacing movement to the platen, means connected to the dragging end of the band to retard the band and cause it to tighten on and grip the drum at the driving stroke of the handle and to tend to return the band around the drum to normal position while the drum is stationaryat the return stroke of the handle, frictional holding means tending at all times to hold the drum and platen stationary and providing for the band being tightened on the drum,-

other holding means supplemental to the first and cooperative therewith to hold the drun and platen stationary while the band is being returned around the drum, and means for eflecting fine variations in the line-spacing movement imparted to the platen at the driving stroke of the handle.

31. In a typewriting machine, the combination with a revoluble platen, of a linespacing mechanism comprising a drum connected to the platen, a band wound several timesaround the drum, a driving handle for drawing upon the leading end of the band to tighten the band on the drum and impart line-spacing movement to the platen,

means connected to the dragging end of the band to retard the band and cause it to tighten on and grip the drum at the driving stroke of the handle and to tend to return the band around the drum to normal position while the drum is stationary at the return stroke of the handle, spaced stops for limiting the line-spacing and return movements of the dragging end of the band, and means for effecting fine variations in the spacing of said stops for correspondingly minutely varying the line-spacing movement imparted 'to the platen at the driving stroke of the handle.

32. In a typewriting machine, the combination with a revoluble platen, of a line'- spacing mechanism comprising a drum connected to the platen, a band wound several times around the drum, a driving handle for drawing upon the leading end of the band to tighten the 'band on the drum and impart line-spacing movement to the platen, means connected to the dragging end of the band to retard the band and cause it to tighten on and grip the drum at the driving stroke of the handle and to tend to return the'band around the drum to normal position while the drum is stationary at the return stroke of/the handle, frictional holding means tending at all times to hold the drum and platen stationary and providing for the band being tightened on the drum, other holding means supplemental to the first and cooperative therewith to hold the drum and platen stationary while the band is being returned around the drum, spaced stops for limiting the line-spacing and return movements of the dragging end of the band, and means for effecting fine variations in the spacin of said stops for correspondingly minute y varying the line-spacing movement imparted to the platen at the driving 7 and drum are mounted, line-space mechanism for the platen comprising a line-space handle, a band wound several times.about the line-space drum, an arm pivotally mounted on said platen axle to which the leading end of said band is connected, another arm on said platen axle to which the dragging end of the band is connected, means operated by the line-space handle to operate the first-mentioned arm to cause said arm to first draw the band tightly about the drum and then rotate the drum, means for returning the band to normal position after the operation of the line-space handle complaten at the driving stroke of the handle.

34. In a typewriting machine, the combination with a revoluble platen, of a linespace drum, an axle on which the platen and drum are mounted, line-space mechanism for the platen comprising a line-space han dle, a band wound several times about the line-space drum, an arm pivotally mounted .on said platen axle to which the leading end of said band is connected, another arm on said platen axle to which the dragging end of the band is connected, means operated by r the line-space handle to operate the firstmentioned arm to cause said arm to first draw the band tightly about the drum and then rotate the drum, means for returning the band to normal position after the operation of the line-space handle comprising a spring connected to the arm which is connected to the dragging end of the band, a spring connected to the leading end of the band to cause the band to be returned in a slackened condition, spaced stops for limiting the movements of the arm connected to the dragging end of the band, means for effecting fine variations in the spacing of said stops for correspondingly minutely varying the line-spacing movement imparted to the platen at the driving stroke ofthe handle, and a stop for the leading end of the band in its return movement.

, 35. .The combination of a revoluble platen, a drum, a flexible band wound around the drum sufiiciently to be self-tightening thereon, a driver connected to one end of the band causing said band to drive the platen, a platen brake to constantly oppose rotation of the platen, and a spring acting between the brake and the dragging end of the band to operate the brake and to return the band around the drum, means being provided for separately and independently adjusting the tension of said spring on the dragging end of the band and on said brake.

BURNHAM c. STICKNEY;

Witnesses:

CATHERINE A. NEWELL, ARTHUR A. JOHNSON.

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