US1874255A - Typewriting machine - Google Patents

Description

Aug. 30, '1932. w. A. -DoBsoN 1,874,255

` l TYPEWRITING. MACHINE Filed April 4, 1929 /r/'gj y WAL '.\\\\\\\\\\\\\\\\\\\\\\\\\\\\x Patented Aug. 30, 1932 UNITED STATES PATENT OFFICE' WILLIAM A.DOBSON, 0F BRIDGEPOBT, CONNECTICUT, ASSIGNOR rTO 'UNDERWOOD EL- l' LIOTT FISHER COMPANYQOF NEW YORK, N. Y., A CORPORATION 0F DELAWARE TYPEWRTTING MACHINE `Application ,legdy April 4, 1929. Serial No. 352,377.

This invention relates to typewriting machines, and more particularly to means for instantly connecting or disconnecting Vthe ratchet-wheel and platen.

In portable typewriting machines, the platen-carriage just its between the sides of the carrying case cover. In Vconstructing the present invention, it is aimed to arrange the mechanism so that the width between the left and right platen `knobs,-wh'ich arethe extreme outer ends of the platen-carriage, should not be extended; n

For this purpose, the releasing mechanism is constructedto fit between the platen and the left-hand "carriage-end plate; and for compactness the releasing mechanism is constructed to extend within the platen, so that the entire mechanism takes up only a small amount of space outside of the platen.

Shortening yof vthe typing line has been avoided, while the distance between the carriageeend plates has remainedv the same.

The construction requires practically no changes in the standard construction of the L Underwood portable typewriter-carriage.

Another feature is that the clutch-mechanism may be operated from either side of the carriage by merely operating either the left or right platen-knob. f

In these portable typewriters the length of the carriage is limited, while the platen is constructed as long as ossible, .so as to accomodate a wide sheet. n devising the. present invention it was necessary that the carriage should not be lengthened, and that the writing line should not be shortened, and furthermore that the usual wide sheet should still be filled out with typed lines. The clutchfreleasing mechanism takes up only the space between the platen and the line-space ratchet-wheel, which, in the present invention, forms the outer end of said clutch-mechanism.

There is used a slidable platen-shaft carrying the platen-knobs.y Movement of theshaft L' is one direction wedges apart the clutch-segments, whichengage and bind' a drum provided on the ratchet-wheel.

lVhen the platen-shaft is moved in a reverse direction, the wcdging means Vwill release the clutch-segments from the drum of the ratchet wheel, which disassociates the platen therefrom, and permits independent spacing of a work-sheet. Through the simplicity of the clutching means employed, it is necessary to exert but a slight pressure on opposite platenknobs, in order to alternately make the ratchet-wheel effectiveor ineffective. It is tantamount also that instead of pressing on oppositeknobs, the same results are accomplished by alternately pressing and pulling on only one knob. For this'reason the connection or release of the ratchet-wheel can be easily controlled from thatend of the carriage which is most convenient to reach.

Another feature of this invention lies in the 'double function incorporated in the wedge, which forces the clutch-segments apart, and concomitantly locksthem in tight frictional engagement with the ratchet-wheel drum.

Due to the springiness of said segments, the wedge sets up tension therein, which aids in increasing the friction by slightly flattening the curves and increasing their holding area. Said springiness also causes the segments to better fill out any'inequalities on the inner surface of the drum, and thus helps to main'- tain frictional engagement. A 'Y e Another feature of this inventien lies'inthe usey of a retaining pinwhich acts as a`fulcrurnforthe wedge, and also holds the clutchsegments in "effective alignment therewith. In assembling the pin andthe wedge, thelatter is bored to have a driving it` for the pin, whereby the pin is held Vafter insertion. In order to permit rotation of the pin when the wedge is swung, the pin-retaining holes of the segments are bored somewhat larger than the pin. These larger Vholes also provide clearance for the segments, so the latter can move along the pin when spread or released by the wedge. Y e Other features and advantages will hereinafter appear. i f

In the accompanying drawing, Figure 1 isa partial longitudinalsection through aplaten and its supports, and shows the parts of this invention as related when the ratchet-wheel is ineffective. v

l Figure v2 isa perspective view of a portion of a platen, and shows some of the parts of 1 this invention associated therewith, and partially broken away.

Figure 3 is a` partial longitudinal section througha platen, and shows parts of this invention as related when the ratchet-wheel has been made effective.

Figure 4 is a detail of parts of the clutch` and shows the segments forced apart by the wedge.

Y Figure 5 isa Ysimilar view to Figure 4, but' with the wedge partially withdrawn to permit the release of the ratchet-wheel.V

Figure 6 is a perspective view'ot parts of this invention, and in proper relationship for assembly.

Figure 7 is aperspective View of parts of this invention, and shows the adjustable devicefor raising or lowering one end of the platen-shaft.

Figure 8 is a perspective detail ot the pivoted wedge, the amount of slope in the wedged faces being indicated in dot and dash.

Referring to the drawing, 10 and 11 are end frames ofa platen-carriage, which form Vpart of a typewriter, not shown. The frame 10 has a countersunk hole 12, in which is inserted a journal 13. The latterhas a shoulder 14 and a turned-down portion 15 which is riveted to the frame. The trame 11 has a clearance hole 16 and an approximately horizrontal slot 17 through which projects a setscrew 18 that is threaded into a block 19. The latter is slidable between two lugs 20 which are attached to or are integral with the frame l1.

In the block 19 is an inclined slot 21, in which can slide the rounded head 22 of a lever 23 which is attached to the frame 11 by a pivot 24. The lever 23 has a countersunk hole 25 in which is inserted a journal 26. The latter has a shoulder 27 ,and a turned-down portion 28 which is riveted to the lever 23. The journal 26 supports a platen-shaft 29 which is slidable therethrough, and which has a flattened area 30. The latter is abutted by a set-screw 31 which attaches a platenknob 32through'gmeans of a connected hub 33.

A set-collar 34 is mounted on the journal 26 and adjustably abuts a hub 35 which forms part of a usual end plate 36. VThe latter is attached by screws 37 to a core 38 which forms part of a platen 39. The latter also has an end plate 40 which is attached to saidV core by screws 41. Said end plate 40 is formed with an inwardly-extending barrel 42 which is axially bored and in which can slide a cylinder 43. The latter has a beveled end 44 to remove any burr that might impede the sliding of said cylinder.

The cylinder 43 is axially bored as at 45 to' support an end of the platen-shaft 29 which is fixed therein through means of a pin 46. Said cylinder also has al larger axial boring 47 which lightens its weight and provides clearance as will appear. The cylinder is slidably supported in the journal 13 and is tightly held in a hub 48 of a platen-knob 49. A pin 50 can also be used to hold said cylinder in said hub. The cylinder has a channel 51, vat one end of which is a hole 52 that extends through the wall.

The end plate 40 has a hub 53 which tightly its inside an end of the core to center and help support the same. The fixity of the two is also furthered by a shoulder 54 which abuts the end of said core. The end plate 40 also has an annular bearing surface 55, a shoulder 56 Aand two hubs 57 and 58. The bearing surface55 supports one end of a rotatable drum 59 whose other vend is turned down and .riveted over an inner beveled edge of a on by a shoulder 63.

The plate 61 has a countersunk hole tor a screw 64 which has a shank 65, a shoulder 66 and a threaded portion 67. The latter is screwed into a threaded hole 68, in the end plate 40. The counter-sinking of the screw 64 prevents the head from hitting extraneous parts when said plate is rotated, while the shoulder 66 limits the thrust and prevents the shoulder 63 from pinching the drum and arresting or retarding its rotation. The shank also servesas a fulcrum for clutchsegments 70 which have approximately semicircular channels 71 that fit thereon.

The clutch-segments 7 0 can swing radially between the drum 59 and the hub 57. The latter also serves tol space the plate 61 from the shoulder 56 which provides side clearance for the swing of said segments. The latter have holes 72 at one end that are larger than a retaining pin 73 which they encompass. The segments therefore can swing radially a sufficient distance before being stopped by said pin. At the ends having the holes 72 the segments are formed with cam-surfaces 73a which normally lie at an angle to each other and will abut a wedge 74.

The wedge 74 has a hole 75 of such diameter as will retain the pin 73 when positioned therein. When assembled the holes 72 will fulcrum said pin as the wedge is rotated through an attached lever 76. The pin also serves to maintain the wedge and the segments 70 in effective relative positions. The lever 76 has a beveled end 77 and a rounded nose 78. Said bevel permits the lever to slide along the channel 51 during assemblage of thel various parts of this invention. Said rounded nose presents a smooth surface to the side of the hole 52 so as'to slide easily when said side actuates the lever. During such movement the lever projects through said hole and into the clearance space 47.

In forming the plate 61 the inner edge has a cut-out 7 9to permit swinging of the llever 76. For the same reason the end plate 40 also has a cut-out 80. In' addition there is a spacing collar 81 between thel frame 10 and the end of the; hub 58. Said' collarmaintains a clearance space for parts of the pawl, not shown. A spring-,pressed detent82 is also shown, as well as a type-head 83. The spacing lever and associated parts, while used with this invention, are common, and for this reason have not been shown.

In lassembling the parts of this invention the components of the bearing on the end plate 11 can be installed first. The platen is then mounted *on its end plates, while the ratchet-wheel and clutch-members are placed in relative association with the endV plate 40.' The screw 64 is then threadedinto the hole 68 to secure the plate 61, and `is fixed by tight ,abutment of the shoulder 66 against the end plate 40 which has previously been inserted and adjusted for this purpose. The knob 49 and the platen-shaft 29 having been attached to the cylinder 43, these unified components are successively run through the journal 13 and the spacing collar `81. j A

As the platen-shaft passes the collar 81 it is run through the platen, which at this time is held centered between the journals 13 and 26. During the transition of the unified shaft, the inwardly-projecting lever 76k will slide along the channel `51 until the nose 78 abuts the end thereof. The set-collar 34'can then be adjusted to abut the end plate 36 vto hold the end plate f40 in rotatable abutment` with the spacing collar 81. Without disturbing the relative positions of the cylinder 43 and the lever 76, the knob 32 is attached to the platen-shaft and in the position shown in Figure 1.

The platen having been mounted in the carriage, it is adjusted if necessary to bring its axis parallel to the line of typing. This is usually accomplished, as previously mentioned, through means of the block 19. It is not wished, however, to limit this invention to the use of only one block, because the same adjusting device in modified form can also be installed at the other end of the carriage. With said device at 'each end of the carriage it is then possible to iiX the platen in various horizontal planes, and thus vary the angleV at which the platen-surface is struck by the type.

Besides spreading and locking the clutchsegments apart, the wedging means maintains the associated cylinder and end plate'in fixed rotative relation. This is accomplished'by the lever of the wedge which passes through the walls of said cylinder and plate. As the lever requires but slight clearance. to swing through said walls, lost motion is minimized when the superposed members are rotated by the cylinder. For this reason the dwell of said plate is negligible when actuated by the 'Y lever and they rotate in unison. Therefore during rotation of the released clutch-members, the wedge does not creep to press a segment against the drum, and the ratchet-wheel remains ineffective.

The drawing illustrates this invention as applied toa portable 'typewriter having a platen-shaft ofsmall diameter. Due to the latter, the cylinder 43 is used to provide an enlarged end that can be machined and still have structural strength. Because the cylinder supports one end of the platen, itforms part of the platenshaft, and if omitted will not nullify this invention. When omitted, a larger shaft is used, the channel 51 is eliminated, the clearance space 47 and hole 52 are incorporated, the cut-out 79 is deepened and the leve-r 76 is lengthened. The assembling is then virtually the same excepting that before final lengthwise setting of the shaft, said lever is projected into said space 47 This invention fthereforeis adaptable to large machines and it is not desired to limit it to the design illustrated.

',Variationsmay be resorted to within the scope of the invention, and portions of the improvements lmay be used without others.

Having thus described my invention, I claim: f 1; In a typewriting machine, the combination with a platen and a shaft, of a linespace wheel freely rotatable about said shaft, a clutch-mechanism to connect said line-space wheel with said platen and including a drum secured to said line-space wheel, a pair of expansible grips having a driving connection to the platen and curved to conform with the inner periphery of said drum, a wedging arm pivotally mounted between two adjacent ends ofsaid grips, said arm having at one end a j pivot journaled in said grips, means engagingthe other end vof the arm with said shaft `for rotary transmission thereby, and actuating means for swinging said arm longitudinally to expand said grips, thereby causing the grips to engage the line-spacewheel drum, and allow the shaft to rotate the line-space wheel together with the platen.

2. In a typewriting machine, 'the combi nationwith a platen having platen-ends conlined between the ends of a platen-frame, of a shaft axially shiftable in `said platen-ends, a linespace wheel adjacent one end ofthe Vplaten and freely rotatable about said shaft,

a clutch-mechanism to connect said line-space wheel with said platen and including a drum secured to said linespace wheel and rotatable upon the adjacent platen-end, a pair of grips having beveled adjacent tips and curved to conform with the inner periphery of said drum, a member rigid upon said platen-end and upon whichone end of said grips may be fulcrumed, an arm opposite to the fulcrumpoint and pivotally mounted between the otherends of said grips and having'a wedging surface to engage said beveled tips, and means upon said shaft to control said arm as the shaft is shifted to expand said grips by awedging action, thus causing the same v to engage the drum, said arm co-operating with said controlling means to form a cou- -pling connectingsaid shiftable shaft to said grips, effective to allow the shaft to rotate the platen.

8. In a typewriting machine, the combination with a platen having platen-ends confined between the ends of a platen-frame, of a shaft axially shift-able in vsaid platen ends, said shaft effective to rotate the platen in every axial shift position of the shaft, a linespace wheel rotatable about said shaft, a drum rotatable together with said line-space Vwheel about said shaft, expansible grips operable to bear against said drum to engage said linespace wheel, a wedge-member pivotally mcuntedbetween two adjoining ends of said grips to cause said grips to engage said drum, said shaft having a recess in which the vfree end of said wedge-member may lodge, so that itA may be swungA between operative and idle position as the shaft is shifted, said wedgemember, in combination with Said recess, serving to rotate said grips together with said shaft.

4. In a typewriting machine, the combination with a platen, a shaft, and line-space mechanism including a disengageable linespace wheel adjacent one end of said platen and rotatable relatively with said platen and shaft, of a clutch-mechanism connecting said platen and line-space wheel, including a drum secured to said line-space wheel, grips curved to conform with the inner periphery of said drum, an arm pivotally mounted between said grips and provided with a wedging surface, means on said shaft to swing said arm about its pivot and cause said wedging surface to press said grips against said drum, and a groove in said shaft to receive the free end of said arm and form a path therefor, to permit the shaft to be removed from said mechanisms.

5. In a typewriting machine, the combination with a platen, a shaft slidably mounted within said platen, and a loose line-space wheel adjacent one end of said platen and rotatable relatively with said platen and shaft, of a clutch-mechanism connecting said platen and line-space Wheel, including a drum secured to said line-space Wheel, grips having beveled adjacent tips and curved to conform with the inner periphery of said drum, an arm pivotally mounted between said grips, and having wedging portions to co-operate with said beveled tips, said arm forming a driving connection between said platen and shaft, when the latter is rotated, but permitting free horizontal movement in both directions ofsaid shaft with respect to said platen, and means on saidy shaft (3o-operating with vsaid arm in each direction of said horizontal movement, to alternately connect and disconneet' the line-space Wheel from said platen.

. 6. In a typewriting machine, the combination of a platen, a longitudinally-adjustable shaft supporting the same, a line-space wheel normally connected in operative engagement With said platen to rotate the same, a clutching device mounted on the shaft, a controller therefor, effective to engage and disengage the wheel from the platen at will, and a pair of shoulders on said shaft, one at eac-h side of the controller, to control the operations of the clutching device by the longitudinal reciprocating movements of said shaft, by direct mechanical engagement with said clutching-device controller, said shaft also including means effective to rotate the platen when the latter is disengaged from said wheel.

7. In a typewriting machine, the combination of a platen, a shaft supporting the same, means for line-spacing the platen by the shaft, including a toothed wheel, a clutch mounted on the platen, effective to engage and disengage the-wheel with reference to said platen, said clutch including a lever pivoted at one end thereto, effective to operate the clutch, and a recess in the shaft to receive the other'end of the lever to engage the lever With'the shaft for swinging the lever into clutch engaging and disengaging position alternately thereby, and effective to engage the platen With said shaft for rotation in both positions of the lever.

' WILLIAM A. DOBSON.

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