US2350510A - Typewriting machine - Google Patents

Description

June 6, 1944.

J. N. HUFFMAN TYPEWRITING MACHINE Filed June 50 1942 2 Sheets-Sheet l a. m 3 w o m II I I war ns s m s J Q a JACOB N. HOFFMAN f ATTORNEY June 6, 1944. J. N. HOFFMAN 'IYPEWRITING MACHfINE Filed ,June so 1942 2 Sheets-Sheet 2 mvzm'on JACOB N. HOFFMAN 78v ATTORNEY Patented J one 6, 1944 UNITED STATES PATENT OFFICE TYPEWRITING MACHINE Jacob N. Hoffman, Bridgeport, Conn., assignor to Underwood Elliott Fisher Company, New York, N. Y., a corporation of Delaware Application June30, 1942, Serial N0. 449,045

10 Claims.

spacing direction and return. In certain of these machines, power mechanism under control of a suitable key or keys is provided for returning the carriage to position to start a line of typing. The line-space frame is operated by the return movement of the carriage as the carriage approaches the end of said movement to move said frame and the type carriage carried thereby forwardly the distance required to start a new line of typing.

In machines of the Elliott-Fisher type, a brake is usually provided for the line-space mechanism which brake performs two functions. The brake holds the line-space frame stationary during the typing of a line and, also, prevents overthrow of the line-space mechanism With resulting variations in the spacing of the lines. This linespace brake is active during the line-spacing action of the line-space mechanism, and the linespace frame is moved against the action of the brake. The braking action or force varies consider-ably under different conditions, and these variations result in variations in the line-spacing movement of the line-space frame.

The primary object of the present invention is to improve the construction and mode of operation of typewriting machines, typewriting-accounting machines and similar machines to avoid the disadvantages in prior constructions above 49 pointed out.

Another object of the invention is to provide typewriting machines and similar machines in which the type mechanism and the means for form and the following detailed description of the construction therein shown.

In the drawings:

Figure l is a view in front elevation, with certain parts in section, illustrating certain portions of a typewriting machine of the Elliott-Fisher type to which the invention is applied,

Figure 2 is a detail view in front elevation, partly broken away and partly in section, illustrating a portion of the mechanism for actuating the line-space frame from the type carriage durmg the latter part of the carriage-return move-- :l'lent' and showing the parts in their normal posiions,

Figure 3 is a detail view in side elevation, partly section, illustrating certain parts of the line-space mechanism and the mechanism for controlling the line-space brake during the latter part of the return movement of the carriage,

Figure 5 is a view in front elevation illustrating a portion of the mechanism shown in Figure 4 with certain of the parts in different positions,

Figure 6 is a view similar to Figure 5 illustratmg certain of the parts in still different positions, and

Figure 7 is a detail view in side elevation illustrating the line-space brake mechanism.

The invention is illustrated in this application as applied to a machine of the type illustrated and described in th patent to Foothorap, No.

5 1,904,127, dated April 18, 1933, and many of the parts have substantially the same construction as the corresponding parts of the machine illustrated and described in said patent. The machine is provided with a carriage-return mechanism having substantially the same construction and mode of operation as the corresponding mechanism illustrated and described in the patent to Sundstrand No. 2,283,401, dated May 19, 1942. The line-space mechanism of the machine, except carrying the paper are moved relatively,after the for the line-space brake and the mechanism for completion of a line of printing, to line space and a brake is provided for the line-space mechanism, with means for controlling the brake to cause a substantially uniform line-spacing action at all 5 times and under all conditions.

With the above and other objects in view, the invention consists in a machine embodying the novel and improved features, constructions and combination of parts hereinafter described and particularly pointed out in the claims, the ad 5 vantages of which will be readily understood and appreciated by those skilled in the art.

The several features of the invention will be clearly understood from the accompanying drawcontrolling the brake, has substantially the same construction, arrangement, and mode of operation of parts as the corresponding mechanism illustrated and described in the patent to Wise 0 No. 2,248,152, dated July 8, 1941.

The machine illustrated in the present application comprises a platen frame provided with side bars or rails 2 connected by transverse bars and a substantially fiat platen 6 mounted for vertical 5 movement in said frame. Upon the side rails of the platen frame is supported a line-space frame movable forwardly and rearwardly on said rails to line-space the type carriage with relation to the platen. The line-space frame comprises side ings illustrating the invention in its preferred brackets or bars 8 connected by front and rear frame to be moved readily over the platen frame.- Of these, the rear rollers are indicated at l2.'

The mechanism for moving the line-spa'ce'frame comprises a shaft l4 rotatably mounted in bearings formed on said frame to Which ..Shaft the rollers I2 are secured, the shaft extending sub stantially parallel with the front and rear rails on theframe. On the shaft are fixed gears it which mesh with the teeth of racks l8v attached to the side rails 2 of the platen frame. The shaft is given a predetermined; angular movement in a counterclockwise direction, Figure 3, adjacent the end of the return movement of the carriage'to impart a line-space movement to the line-space frame.-"'

The type carriage, a portion of .which is illustrated in Figure l and indicatedat20, isprovided with wheels or rollers 22 which engage the upper edges of the front. and rear rails of the line-space frame so that the carriage is movable transversely of the machine along said railsto impart forward and return movements to the carriage. The carriage is connected-by a flexible band 23 to the usual spring drum 25 which tends constantly to draw the carriage in'a right-hand direction across the machine. a

The machine embodying the present invention is preferably provided with automatically operating mechanism controlled alternatively by suitable keys or by the movement of the type carriage for imparting return movements to the carriage. V a a The mechanism for turning the shaft Mto actuate the line-space frame comprises a wheel 26 attached to oneend of said shaft and having a series of relatively fine teeth on its periphery which are'engaged at intervalsby a pawl 28 pivoted at 30 on'a pawl carrier 32 mounted to turn onthe shaft. A pawlactuating bell crank 34 is also pivoted on said; shaft andis provided a with a pin'or stud36 on one arrrr'thereof en' gaging in a slot '38 in the outer portion of the pawl. The pivotal movementof the pawl 28, with relation to the pawl "carrier 32, is limited by means of a pm All projecting from the pawl carrier and engaging in a-recess' 42 in the lower portion of the pawl. The pawl carrier and the pawl actuator are acted upon, respectively, by coil springs 44 which tendfto swing the carrier and actuator in a clockwise direction, Figure 3; The pawl'carrier and pawl actuator, are normally held substantially in the positions shown in Figure 3 with the pawl in engagementwith a stop position. The pawl actuator is swung in a counterclockwise direction, Figure 3, to actuate the shaft ll, to impart a forward movement to the line-space frame, just before the'completion of each return movement of the carriage, from the --movement of the carriage.

' The mechanism for actuating the pawl 28 from the. carriage will now be described. The other end ofa rockshaft 58 mounted in hearings in the 46 on the line-space frame, and thepawl is thereby held out of engagementwith 1 the toothed wheel 26.

In actuating the toothed wheel, the pawl actu ator 34 is swung in a counterclo'ckwise direction,

Figure 3. During this movement of the actuator,

the pawl is first engaged with the toothed wheel and the pawl carrier and toothed wheel are then turned with the pawl actuator untilvthe movement of the pawl is arrested, The movem'ent of the pawl is arrested to limit the line-space v movement Vbyjrneansof astoppin .48 mounted on a bracket 50, attached to theiine space frame and arranged to engage the forward side of the pawl is arrested, locks the line-space frame in 7 of the machine.

arm of the pawl actuator is connected by a link .52 with one end of a lever 54 secured to the rear line-spaceframe and extending toward the front The other end of said lever is connected by a link 58 to an arm 68 secured to the rear end of a relatively short rock shaft 62 also mounted in' bearings in the line-space frame. To the forward end of shaft 62 is fixed an arm 64,- which is connected by means of a coilspring 65 with the lower arm of a lever 68 pivoted to "turn freely on the forward end of the shaft 62. The upper arm of the lever 68 is provided with a forwardly turned flange 10 which is arranged to be engaged'by a pin 12 carried at the left-hand end ofan actuating pawl or dog 14 pivoted on 'a'stud' 16 secured to a plate 18 forming a'slide mounted on the line-space frame and movable transversely of said frame. The dog 14 is acted upon by a coil spring which tends to swing "the left-hand end thereof downwardly to carry the pin 12 into operative position with relation to- -the contact flange 10 on the lever 68, the movement 'of the pawl under the action of the spring being limited by means of a pin 82 projecting from the plate 84 secured to the slide 18 in spaced relation thereto, as shown in Figure 2.

During the entire movement of the carriage, except the first part of the advance movement and'the last part of the return movement thereof, the'slide 18 is held substantially in the position shown in Figure 2; After the first part of the advance movement of the carriage, and during the entire return movement thereof, the dog 14 is maintained by the spring- 80 substantially 'in the position shown in said figure. As the carfriage executes the last part of its return movement; the slide 18 is moved. to the left with the carriage; and through the engagement of the pin 12 on the dog 14 with the contact flange 18 on the lever 68, the lever is actuated to impart a line-spacing'movement to the pawl carrier 32 normalposition shown in Figure 2. The slide 18 is provided with substantially parallel guide slots 86 and 88 in which engage, respectively, a guide stud 98 and the shaft 62, and the plate is held in position on the guide stud and shaft by means of holding plates or washers 94 and 96. The movement of the slide 18 toward the left is stopped by the engagement of the left-hand end of a projection or beak 95 on the slide with a jfixed stop 91 secured to the right-hand end of the rear rail Ill.

The mechanism for moving the slide to the left, from the position shown in Figures 1 and 2, during the last part of the carriage-return movement, comprises a draft rod 98 and mechanism for actuating said rod, during the return movement of the carriage having substantially the same construction and mode of operation as the corresponding mechanism disclosed in said Sundstrand and Wise patents, referred to above. The draft rod is mounted in a channel formed by the front face of the rear rail l0 and the rear face of the carriage escapement rack I00. The right-hand end of the draft rod is connected bymeans of an attaching plate I02 to the slide I8. The left-hand end portion of the draft rod is. guided by any suitable guide means (not shown).

The left-hand portion of the draft rod is provided with teeth upon its upper face and upon the draft rod are mounted a series of arresters I04, I06 and I08 of different heights engaging said teeth and adjustably arranged on the rod at different distances from the left-hand end thereof. The arrester I04 having the greatest height and located nearest the left-hand end of the draft rod is arranged to be engaged by the abutment plate .I I!) secured to the carriage 20 to arrest the carriage at the end of a full return movement thereof. The arresters I 06 and I08 are arranged to be engaged alternatively by a check stop II2 mounted on the carriage and protrudable to different positions to engage selectively the said arresters at different points in the return movement of the carriage. Thus the return movement of the carriage will be arrested with the carriage in different positions, respectively, by'the engagement of the abutment II with the arrester I04 and by the engagement of the protrudable check stop H2 withthe' arresters I06 and I08.

As the carriage approaches the end of its return movement, the abutment III: on the carriage engages the arrester I04 or the check stop II2 engages one of the arresters I06 and IE8 and the draft rod is moved to the left with the carriage thereby carrying the slidel8 therewith, and the carriage is finally arrested by the engagement of the projection 95 on the slide with the stop 91 which arrests the movement of the slide and the draft rod. During this movement of the slide, the line-space mechanism is actuated through the connections described to impart a line-spacing movement to the line-space frame.

The machine illustrated in the present application is provided with an electrical driving motor and with driving connections including a shiftable clutch for returning the carriage by power. The machine is also provided with carriage-return keys and mechanisms controlled by the keys, respectively, for projecting or protruding the stop H2 and for causing the engagement of the carriage-return clutch. The mechanisms for driving the carriage to return position and the mechanisms for controlling the engagement and disengagement of the carriage-return clutch and for controlling the position of the protrudable stop H2, in the present machine, have substantially the same construction, arrangement, and mode of operation as the corresponding mechanisms, illustrated and described in the patent to Sundstrand and the patent to Wise, referred to above.

The machine is provided with the usual linespace brake mechanism to hold the line-space frame firmly in position during the writing of a line and to prevent overthrow of the line-space mechanism during the line-space operation. The line-space brake mechanism comprises the rollers I2 which serve as brake discs or drums and brake shoes II4 arranged to'engage, respectively, said brake discs. Eachof the brake shoes is pivotally supported at H6 on an arm H8 pivoted on a pin or stud i2!) mounted in a cylindrical boss I22 projecting inwardlyfrom an upright I24 on the line-space frame. To each arm H8 is fixed, in spaced relation to said arm, a downwardly extending arm I26 and said arm is acted upon by :a coil spring I28 which tends constantly to swing the arm forwardly and thereby engage the corresponding brake shoe with the brake disc I2.

To the lower end of each of the arms I26 is pivoted, at I 30, the rear end ofa push rod I32. Each push rod extends from the-corresponding arm :l26forwardly and the forward portion of the rod engages in a guide I34 attached to the underside of the rearrail I0. The forward end of each push rod engages the rear side of a cradle or trough-shaped bail I36 having brackets I38 adjacent its ends, by means of which, the ball is pivoted at I40 to brackets I42 fixed to the forward side of the rear rail I0.

With this construction, the brake .shoes H4 are normally held in engagement with the brake discs I 2 so that the line-space frame is held firmly in position with relation to a work sheet, clamped to the platen, during the typing of a line. Upon a downward pressure of the forward portion of the bail I36, the push rods I32 are 7 moved rearwardly and the arms I26 are swung rearwardly against the action of the springs I28 to release the brake shoes H4 from the brake discs I2. When the ball is released ,the arms I26 are swung back forward by the springs I28 to engage again the brake shoes H4 with the brake discs.

In the present machine, as the carriage approaches the end of a return movement, the linespace brake is automatically released so that the line-space frame is free to move under the action of the line-space mechanism. The action of the line-space mechanism, therefore, is not subject to the variations in braking conditions usually met with, and a much more uniform linespacing operation is obtained. At the extreme end of the line-spacing movement of the linespace frame, the line-space brake is again engaged so that it effectively prevents overthrow of the line-space mechanism.

The mechanism for controlling the line-space brake, during the latter part of the return movement of the type carriage, comprises a lever I44 pivoted at I46 upon a stud projecting forwardly from the rear rail I0 and having a forwardly bent portion I48 which overlies a finger I50 on a bracket or plate I52 attached to the forward side of the bail I36. The lever I44 is connected with a second lever I54 by means of a pin I56 secured in, and projecting forwardly from the lever I54 and engaging in a slot in the adjacent end of the lever I44. The lever I54 is pivoted upona stud I58 secured in, and projecting forwardly from the rear rail I0, and the springs I28, acting on the arms I26, through the intermediate connections described, tend to swing the lever I54 in a clockwise direction, Figures 4 to 6, inclusive. The lever I54 is provided with a rearwardly bent projection I60, and the movement of said lever in a clockwise direction is adjustably limited by means of a set screw I62 threaded into a portion I64 of the line-space frame and arranged to be engaged by said projection. Ph oted on the stud I58 at the rear of the lever I54 is a third lever I66 and said lever is acted upon by a coil spring I68 which tends to swing the same in a clockwise direction, Figures 4, 5, and 6, the movement of said lever; under the action of the spring, being limited by means of a pin I10 projecting from the rear rail III. The lever I66 is connected with the lever I54 to actuate the latter lever under certain conditions by means of a latch I12 slidably mounted on the lever we; the right-hand end of which latch is normally'located above the left-hand end of the lever I 54 in position toengage the latter lever upon a counterclockwise movement of the lever "I66, as shownin Figures 4and-5. 'The latch I12 is provided with slots I14 and-is .slidably mounted upon the lever ;I66- by means 'of studs I16 secured-in the lever I66 and engaged in said slots. The 'latch I 12" is "acted upon by a coil spring I18 connecting the same with a pin I80 mounted on the lever I54 which tends to move the latchto'the right, Figures 4, 5, and 6, to connect operatively levers I66 and I54. 1

-With this construction, and with the parts in normal positions, as shown in Figure 4, upon latch I12 engages the left-hand end of the lever I54, and the latter lever is'swung in a counterclockwise direction with the lever I66. This movement of the le'ver' I54 swings the lever I44 in a'clockwise direction, Figures 4, 5, and 6, and the forward portion of the bail I36 'is depressed to release the line-space brake, Upon'the release of the lever I54 by the latch I12, the linespace brake is again engaged by the action of the springs I28. As the carriage approaches the end of a return movement, the parts are located substantially in the positions shown in Figure 4, and the left-hand end of the lever l66is depressed to actuate the lever I 54 through the latch torelease the line-space brake. I As the carriage reaches the extreme end of its return movement, the latch I12 is moved to the left to'carry the right hand end of the latch beyond the lefthand end of the lever I54, thereby releasing said lever, and the line-space brake is again engaged by the action of the springs I28. z

The mechanism for actuating the lever I66 comprisesa roller I84 mounted in a b1ock I86 attached to the downwardly extending 'arm' of a bent plate or bracket I88 fixed to the left-hand end of the draft rod 98 by means of abox nut I98, and having a slot in which engages a guide plate I9I attached to the frame to guide the end of the rod'and hold the same from upward movement. The block I86 carries a pm I 92 to which is attached one'end of a coil spring I94, theother end of which is connected to a point on the line-spaceframa This spring normally retains the draft rod 98 and the plate 18 in their right-hand positions and restores them to said positions after they are moved to the left by the return movement of the carriage. The roller I84 is arranged toengage the upper edge of the lever I66 which is shaped as shown clearly in Figure 4. During thenormal operation of the machine, the parts assume substantially the position shown in Figure 4; As shown in this fig- -ure, the roller I84 then occupies a lower portion of the upper edge of the lever I66. i Asthe carriage approaches the end of a return movement, by the'engagement of one of the abutments'or stops on the carriage with one of the arresters carried'by the draft rod, the draft rod is moved to the left, Figures 4, 5, and 6. The upper edge of the lever I66 is provided with portions I98 inclinedwhen the lever is in normal position, so that the'leftward movement of the bracket 188 and the roller I 84 depresses the left-hand end of the lever I66, thereby swinging the left-hand end of the lever I54 downwardly to release the line-space brake. The upper edge of the lever I 66 is provided with a portion 208 which is engaged by the roll I84 after depressionof the left-hand end "of the lever. This portion 200 of the lever 'ile'p'ression of the left-hand end of lever I66, the

constitutes a dwell portion, when that part of the lever to the left of its axis (Figs. 4, 5, and 6) is depressed, to hold the, brake disengageduntil the carriage-reaches the-extreme end of its return movement. l

In order to disconnect the levers I68 and I54, when the carriage reaches the extreme end of its return movement, the slide I12 is formed with an upwardly extending-projection 292 which is then engaged by the roll and the slide is thereby moved to the left to disengage the right-hand end of the slide from above the left-hand end of thefilever I54. This releaseslever I54 and the lever I44, and the line-space brake is then again engaged by the action of the springs I28.

As the carriage is moved forwardly following a return movement, the draft rod '98 is moved forwardly substantially to. the position shown in Figure 4 by'the action of the coil spring I94; During this movement of the draft rod, the movement of the roller I84, along the upper edge of the lever, I66, allows the lever to be restored substantiallyto the position shown in Figure 4, by the action of'the coil spring I68, and the latch I12 is then moved to the rightinto'position above the left-hand end of the lever I54 by the coil spring I18. This restores the parts to their original, or starting positions;

It is to be understood that the invention is not limited to' the particular construction and arrangement of parts of the illustrated form or embodiment of the invention, but that the invention may be embodied in other'forms within the scope of the claims.

Having explained the nature and object of the invention, and having specifically described a construction embodying the invention in its pre-' ferred form, what is claimed is:

1. 'A typewriting machine comprising a supporting frame, a substantially flat platen, a linespace frame mounted on said'supporting frame for movement forwardly and rearwardly over the platen, a type carriage mounted on the linespace frame for movement in letter-spacing direction and return, mechanism for advancing the carriage to letter space the same, means'operated by the movement of the carriage for moving the line-space frame to'line space adjacent the end'of the carriage-return movement, a normally active brake for the line-space mechanism, and means for releasing said brake as the carriage approaches the end of its return movement-and for restoring the brake at the extreme end portion of the line space movement of the line-space mechanism. 2. A typewriting machine comprising a sub,- stantially fiat platen, a line-space frame mounted for movement forwardly and rearwardly over the platen, a type carriage mounted on the line-space frame for movement in a right-hand direction to letter space and in a left-hand direction to return the same, mechanism for advancing the carriage to letter space the same, means operated by the movement of the carriage for moving the line-space frame to line space as the carriage approaches the end of the carriage return movement, a normally active brake for the line-space mechanism, and means for releasing said brake as the carriage approaches the end of its return movement and for restoring the brake immediately prior to the end of the line-space movement of the line-space mechanism. Y 1

3. A typewriting machine comprising a supporting structure, a substantially flat platen, a line-space frame mounted on said structure for movement forwardly and rearwardly over the platen, a type carriage mounted on the line space frame for movement in letter-spacing direction and return, means for advancing the carriage to letter space the same, mechanism for moving the line-space frame to line space, a normally active brake for the line-space mechanism, and means for releasing the brake during the greater part of the line-spacing action of the line-space mechanism and for restoring said brake just before the end of the line-space movement of said mechanism.

4. A typewriting machine comprising a frame, a substantially flat platen, a line-space carriage mounted on said frame for movement forwardly and rearwardly over the platen, a type carriage mounted on the line-space carriage for movement in letter-spacing direction and return, mechanism for advancing the type carriage to letter space the same, means for moving the linespace carriage to line space, a holding device for the line-space carriage, means for maintaining said device in action during the advance of the type carriage, and mechanism controlled by the movement of the type carriage for throwing said holding device out of action and for causing the restoration of said device to action.

5. A typewriting machine comprising a substantially flat platen, a line-space frame mounted for movement forwardly and rearwardly over the platen, a type carriage mounted on the linespace frame for movement in letter-spacing direction and return, mechanism for advancing the carriage to letter space the same, means for moving the line-space frame to line space, a brake for the line-space mechanism, means for normally maintaining the brake engaged, and mechanism for releasing the brake during the greater part of the movement of the line-space mechanism and for causing the restoration of the brake just before the completion of said movement.

6. A typewriting mach ne comprising a supporting structure, a substantially flat platen. a line-space frame mounted on said supporting structure for movement forwardly and rearwardly over the platen. a type carriage mounted on the line-space frame for movement in letterspacing direction and return, means for advancing the carriage to letter space the same. mechanism for moving the l ne-space frame to line space, a holding device for the line-space frame, means for maintaining said holding device in action during the advance of the type carriage and during the greater part of the return movement thereof, said mechanism including a transverse draft rod mounted on the line-space frame and moved longitudinally during the return of the carriage, and means carried by the draft rod for rendering inactive said holding device during the greater part of the line-spacing action of the said mechanism.

7. A typewriting machine comprising a frame, a substantially fiat platen, a line-space frame mounted for movement forwardly and rearwardly over the platen, a type carriage mounted on the line-space frame for movement in letter-spacing direction and return, means for advancing the carriage to letter space the same, mechanism for moving the line-space frame to line space, a normally active brake for the line-space mechanism, said mechanism including a transverse carriage, means for releasing the line-space brake, and mechanism carried by the draft rod for actuating said releasing means to release the brake during the greater part of the line-spacing action of the line-space mechanism and for causing restoration of the brake just before the line-spacing action of said mechanism is completed.

8. A typewriting machine comprising a supporting frame, a substantially fiat platen. a linespace frame mounted on said supporting frame for movement forwardly and rearwardly over the platen, a type carriage mounted on the linespace frame for movement in letter-spacing direction and return, means for advancing the carriage to letter space the same, mechanism for moving the line-space frame to line space, a normally active brake for the line-space mechanism, said mechanism comprising a transverse draft rod mounted on the line-space frame and moved longitudinally during the latter part of the return movement of the carriage, a bail for controlling said brake, one or more levers for actuating the bail, and means carried by the draft rod for actuating and controlling said levers to release the brake during the greater part of the line-space action of the line-space mechanism and for causing the restoration of the brake immediately prior to the end of the line-spacing movement of said mechanism.

9. A typewriting machine comprising a substantially flat platen, a line-space frame mounted for movement forwardly and rearwardly over the platen, a type carriage mounted on the linespace frame for movement in letter-spacing direction and return, means for advancing the carriage to letter space the same, mechanism for moving the line-space frame to line space, a normally active brake for the line-space mechanism, means for controlling the brake during the latter part of the line-spacing action of the linespace mechanism comprising two cooperating levers, a latch movably mounted on one of the said levers for engaging the other lever to actuate the same, a spring for maintaining said latch in position to engage the latter lever, means for moving the first lever while the latch is in operating position to actuate the other lever to release the brake substantially at the beginning of the line-spacing movement of said mechanism and for actuating the latch to disconnect the levers to allow the restoration of the brake at the extreme end portion of the line-spacing movement of said mechanism.

10. A typewriting machine comprising a supporting frame, a substantially flat platen, a linespace frame mounted on said supporting frame for movement forwardly and rearwardly over the platen, a type carriage mounted on the line-space frame for movement in letter-spacing direction and return, mechanism for advancing the carriage to letter-space the same, means operated by the movement of the carriage for moving the line-space frame to line-space adjacent the end of the carriage return movement, a normally active holding device for the line-space mechanism and means for rendering inactive said holding device as the carriage approaches the end of its return movement and for restoring said holding device to action at the extreme end portion of the line-spacing movement of the linespace mechanism.

JACOB N. HOFFMAN.

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