US1899034A - Typewriting machine - Google Patents

Description

Feb. 28,, 1933. w HELMQND 1,899,034

'TYPEWRITING MACHINE Filed May 2, 1930 INVENTOR:

Patented Feb. 28, 1933 UNITED STATES PATENT OFFICE WILLIAM HELMOND, OF WEST HARTFORD, CONNECTICUT, ASSIGNOB 1'0 UNDERWOOD I ELLIOTT FISHER COMPANY, OF NEW YORK, N. Y., A CORPORATION OF DELAWARE IYTPEW'BITING MACHINE Application filed Kay 8, 1830. Serial No. 449,177.

This invention relates to the tabulati mechanisms for the carriages of Underwoo and other typewriting machines, and the means for controlling the speed of the released carriage.

Certain of the improvements are suitable for typewriter-carriages of standard length having about ei ht inches travel, but one of the objects of t e invention is to improve the tabulating mechanism of a long carriage and also to improve the action of the carriage when released. Sometimes a long carriage travels twenty-four inches or more, and occasionally the carriage ma jump fifteen or twenty inches, and it is desired to prevent the carriage from gaining undue momentum in a long jump. The long carriages are heavy, and injury would occur to the machine by suddenly arresting the heavy carriage if running at high speed. On the other hand, it is desired not to devote too much time to the carria e-jumping operation.

In the nderwood typewriters that are used for typing ordina correspondence in which there is not muc occasion for ta u- 'lating, it is contrived that the key which releases the carriage at the tabulating operation shall also press a stationary bar against a brake-pad that is fixed on the carriage, so that the jumping carriage is subjected to some restraint. The carriage, however, is not fully under control, although little or no injury results from sudden arrest of the carriage, since the carriage is light and since the tabulating mechanism is used infrequently. The friction pad is subject to wear. v

In some machines there is provided an extra rack u n the carriage, which meshes with a pinlon, and thereby rotates a friction disk, which serves as a check against excessive carriage speed. This does not insantly check the carriage, and, moreover, the friction is usually inetlicient where the carriage has a long range and is traveling at increasing speed.

Machines have also been made'with centrifugal governors, Where the pressure of the carriage-brake is increased by the increasing speed of the carriage, but these may allow the carriage to make a considerable jump without checking it at all; and if the speed of the carriage should rise very much, the centrifugal governor would supply too great a brakmg power. Any kind of a revolving brake has to be set for a certain carriage speed, but at other speeds the brake -is apt to develop faults.

All of the centrifugal devices are expensive and add to the Weight of the carriage and moving parts.

An object of the resent invention is to provide a simple an inexpensive carriageretarding device, which is also reliable, and is efficient for both long and short 'umps of the carriage, and prevents shocks from sudden arrest of the rapidly moving long heavy carriage, and does not require to be set for any speed, and is economical of time of the tabulating operation, and places the action of the carriage entirely under the control of the operator.

In the preferred manner of carr ing out the invention, a brake-strap is exten ed from one end of the carriage to the other. Upon the machine-frame there is provided a pair of jaws, faced with leather or suitable padded friction material; these jaws bein adapted to bite upon said strap. One of t e jaws is movable, and is connected to the tabulatorkey that releases the carriage from the control of the escapement-mcchanism; the other jaw does not need to move.

When a tabular-key is depressed, one jaw presses the brake-band a ainst the other jaw, and as the band travels, t ere is a double friction incurred, one upon each surface of the band, so that the efficiency of the brake is double, and it is easily controlled by the key. There may be suflicient flexibility of the band to insure the desired coaction between the same and the friction jaws, since even if the band is slack, the movable jaw brings it firmly against the fixed .jaw. Moreover, it is no longer necessary to rovide an accurately formed and mounted rake-bar having coaction with a single brake shoe, as heretomay occur in the travel of a longcarriage.

4} riage-brakin The active jaw is provided with an arm which carries a stationary counterstop, which is projected into the path of the colum'n-stops mounted upon the typewriter-carriage.

e rocking jaw also has an arm which operates the carriage-release mechanism, and t e parts are so set that the carriage is released at the moment that both shoes grip the brake-band; but the carriage-releasing mechanism is capable of bein still further rocked, to permit the movableirake to force the band harder against the stationary brake, so as to retard the carriage more effectively.

The device is sufliciently under the control of the operator to rmit him to release the carriage and let it ump freely for nearly all of a long stroke, and the pressure u on the tabulator-key may be increasedsharp y near the end of the carriage-stroke, thereby grad-- ually checking the carriage and preventing shock when arrested by the column-stops. This is a time-saving device, since the operator does not have to wait while the carriage takes a long time in making long jumps slowly.

The carriage is suitably checked b the opertaor, and not too sharply arreste and has little or no tendency to rebound, thus overcoming a drawback in tabulating typewriters.

A further improvement relates to the manner of mounting and operating the column-, stops on the carriage, and one of its main objects is to compact the column-stop mechanism, to lighten it, and reduce its cost and make it more reliable. To the end portions of a carriage are attached rearwardly-extending brackets, which carry a column-stop bar having teeth on opposite sides, the column-sto s having forks inserted between the teeth the bar. The above-mentioned brake-band is placed near the top of the carriage, extending along its rear. Above the bar is mounted a column-stop locatin scale, and this scale can be swung upwar y and forwardly to a position for convenient reading. While it is swung up, the column-stops are arranged along the bar asdesired, to

;, make use of the scale when locating the stops.

Then the scale is pressed down and a flange that is provided upon the scale locks the coluxnn-sto upon the bar.

The a oresaid arm which carries the carjaw is hinged upon the fixed framework 0 the typewriting machine, preferably upon the standards which carry the rear carriage-guide rod. Said jaw extends upwardly and rearwardly from its hinge, a column-stop being secured to the upper end of the arm just behind and below the column-stop rack, the whole making a very compact structure at the rear of the paperca The main stop extends radially Q of ita pivot, and therefore o cupies an oblique position when viewed inside elevation. The column-stop bar is given a correspondin obliquity for compactness, efliciency, lig tness and fnexpensiveness. Moreover the brake does not ress against the carria 0 itself, and thus t ere is obviated the ten ency of the usual brake to cause the carriage to bind and wear upon its tracks.

Other features and advantages will hereinafter appear.

In the accompanying drawing,

Figure 1 is a fragmentary perspective view of an Underwood typewriting machine having my invention applied thereto.

Figure 2 is a partial cross-sectional view, from front-to rear, of the structure shown in Figure 1, the braking mechanism being shown in released position.

Figure 3 is a view similar to Figure 2, the braking mechanism being shown in effective position.

Figure 4 is a diagrammatic view, illustrating the operating principle of my improve brakt'ng mechanism.

Figure 5 is a detail view, illustrating the construction of one of the brake-jaw members of my invention.

In the typewriting machine, types strike against a platen 11 on a platen-shaft 12, mounted in a carriage 13, traveling on a front rail (not shown) and a rear rail 14, mounted upon a main frame 15.

As a type 10 is swung by a key against the platen 11, the carriage 13 is letter-spaced to the left by a spring-motor 16 and band 17. Av rack 18, displaceably mounted on the carriage 13, normally engages a pinion 20, fastened to a ratchet-wheel 21, whose step-bystep rotation is controlled by dogs 22, mounted on the main frame for operation by a universal bar (not shown). The abovenamed parts are, found in the Underwood long-carriage typewritt'ng machine.

A flexible carriage-braking strap 23 is mounted upon the carriage by means of a rearwardly-extending bracket 24, secured by screws 25 upon a crosswise frame-member 26 at the rear side of the carriage. A rearwardly-extending bracket 27 may be mounted by screws 25 on the frame-member 26. adiacent the other end of the carriage 13. The wear-resisting brake-strap 23 may be made of suitable flexible metal, and may have each end' fastened, as by screws 28, to fastening members 30. One member 30 is secured strongly by screws 31 to the bracket 24 and the other to the bracket 27 in a like manner by screws 31.

For compactly mounting the various elements of the mechanism, the brake-strap-fastening members are preferably shaped substantially as shown in Figures 1 and 2, and nprmally hold the brake-strap 23 in an oblique p ane.

A bifurcated brake-jaw, generally desigescapee nated as 32, is mounted in the rear of strap 23, and a fixed brake-j aw, generally designated as 33, in front of the strap. A rock-shaft 34 is mounted on pintles 35 of studs 36, threaded in usual corner-post extensions 37 of the main frame 15. The brake-jaw 32 has two branches 38 coaxially apertured for engaging with a tight fit on the shaft 34, adj aoent the ratchetwheel 21, a short distance to the rear of the latter. A set-screw 40 engages through each branch 38 and secures the brake-j aw member 32 on the shaft 34, to provide angular movement of the member and the shaft together. A brake-shoe element 41, of cork or other suitable material, may be securely fastened to the brake-jaw member 32, so as to be disposed opposite from and nearly parallel to the strap 23 in the rear thereof.

The brake-j aw member 33 may be formed from sheet-metal, and have two branches 42, each curled around the shaft 34, to permit the member 33 to turn about the shaft. The outside width of the branches 42 is such that they will fit snugly between the branches 38, and are thereby held against lateral displacement. A brake-shoe element 43, of a material like the shoe-element 41, may be fastened, as by rivet-s 44, to the jaw-member 33, so that its work-face will be disposed parallel to and closely adjacent the strap 23.

A torsion spring 45 is coiled about the shaft 34 between the branches 38, and one end of the spring presses against the member 32, and the other end presses against the member 33. To holdthebrake-j aw member 33 against angular movement, it has an integral forwardly-extending stop-lug 46 with a down-turned portion 47 arranged for engaging a ainst a usual ball-bearing casing 48, which orms an element of the escapement-mechanism, and is supported by the frame 15.

When it is desired to have the carriage 13 move leftwardly a predetermined distance, more than a single letter-space, the operator depresses tabulator-key 50, mounted on a keylever 51, which is fulcrumed about a usual rod 52, the depression of the key-lever being yieldingly resisted by a spring 53. The key-lever 51 is connected by an upwardly-extending link 54 to a forwardly-extending arm 55, fastened in the shaft 34. The link 54 has a slot 56 engaging about a pin 57 in the lever 51, and the link is loosely fastened to the arm 55 by a screw 58.

A tappet 60, fastened in the shaft 34, extends forwardly andterminates in a ball-element 61. The ball 61 is disposed adj acent. an upper face of the rear end of a lever 62, which extends forwardly under the rack 18, and is pivoted between the ball 61 and the rack on a rightwardly-extending stud 63, fastened in a usual upright column-element 64 of the main frame 15, provided for mounting the escapement-mechanism.

A roller 65 is mounted on the end of the lever 62 in a substantially vertical plane, and is normally disposed a short distance below a shoulder-element 66 at the base of teeth 67 on the rack 18. The work-face of the brake 41, in starting position, is spaced from the workface of the brake-shoe 43 a distance having a predetermined relation to the distance of the uppermost part of the roller 65 from the shoulder 66, so that upon initial depression of the key 50, the brake-shoe 41 moves the brakestrap 23 up against the brake-shoe 43 net before the roller 65 is swung up far enou h to raise the rack 18 out of engagement wit the pinion 20.

Upon disengagementof the rack 18 and the pinion 20, the spring-motor 16 moves the a carriage 13 to the left at a speed which varies according to the pressure of the brake-shoes 41 and'43 on the strap 23, which moves between the brake-shoes, being connecied to the carriage. The pressure of the brake-shoes 41 and 43 on this strap can be controlled by the pressure of the operators finger on the key 50.

To bring the carriage 13 to a stop after it has been released from control of the letterspace mechanism, an upreaching stop-tooth 70 is integrally joined to a base-member 71, mounted on a rear extension 73 of the brakejaw 32, as by rivets 72. Also the base-member may have a key element 74 for engaging izn a suitable slot in the brake-jaw extension A rack 75, of rectangular cross-section, has teeth 76 of a well-known form cut in two opposite faces, the teeth being one letterspace distance apart. The rack may be mounted on a carriage by means hereinafter described in an oblique plane substantially parallel to the plane of the brake-strap 23. Bifurcated column-stops 7 7 of a usual design are mounted on the-rack 75 at desired points, such as those corresponding to columnar divisions of a. work-sheet (not shown). The rack 75 is positioned so that when the brakej aw member 32 is swung up to effective braking position, the tooth 70 is moved into the path of the column-stops 77 on the rack 75, and the nearest stop to the right of the tooth 70 is moved squarely up against it and brings I help to transmit the carriage-stopping impact strain coming on the rack 75 to the left extension 80.

A feature of the present invention resides in the provision of an improved tabular scale.

it w

'ward displacement on two pivoted hingeinembers 88, one at each end of the crosspiece 86; Each hinge-member has a rearward shelf-extension 89, on which the crosspieoe 86 rests, and an integral forwardlyextending flange-element 90, which is apertured for receiving a pivot-screw 91, which is threaded in an upwardly-extending arm 92 of a bracket 93, mounted on top of the end portion of the rack by the screws 81.

The cross-piece 86 serves an additional purpose by having a down-turned flange-member 94, whose lower edge normally engages behind a usual shoulder of the column-stops 77. The crossiece thereby serves as a lockdevice for holdin the column-stops securely in position. A eaf-spring detent-member 96 may be mounted on the left-hand bracket 93 by one of the screws 81. When it is desired to reset the column-sfiops 77. the detentspring holding screw 81 may be slightly loosened, the spring swung aside, and the cross-piece swung up to the position indicated in dot-and-dash o'utline in Figure 2. The column-stops 77 may then be changed, and the crossiece swung down again and secured in pliice by the detent-member.

Variat1ons may be resorted to within the scope of the invention, and portions of the improvements may be used without others.

Having thus described my invention, I

claim:

1. In a typewriting machine, the combination with a laterally movable carriage, means for urging said carriage in the direction of i s letter-s ace travel, and mechanism for letter-spacing said carriage, of key-controlled means for releasing said carriage from said letter-spacing mechanism, whereby it is free to be moved rapidly by said urging means, instrumentalities for applying a manually variable braking force to the released car riage to retard the lateral movement thereof, said instrumentalities including a laterally disposed brake-strap on said carriage and two laterally fixed brake-jaw members mounted on said machine on opposite sides of said strap. one of said jaw-members movable for pressing said brake-strap against the other aw-member as it moves with said carriage between them. and devices for stopping said carriage, said stopping devices including laterally adjustablecolumn-s"ops on said carriage. and a stop-tooth on said movable brakejaw member movable into the path of said column-stops upon the operation of said braking-force instrumentalities.

2. In a typewriting machine. the combination with a stationary main frame. a left 'wardly-urged carriage and a letter-spacing releasing said carriage from control of said" letter-spacin mechanism, including a laterally dispose rock-shaft on said mam frame,

a key operatively connected to said shaft for rotatively movin the same, and a connection between said sha t and said mechanism, a laterally disposed strap on said carriage substantially parallel to said rock-shaft, two latorally-fixed brake-jaws on said rock-shaft arranged for pressing said brake-stra between them upon rotation of said sha by said key, a settable carriage-stop on said carriage, and a member on one of said brake-jaws arran ed for engaging said carriage-sto and arresting the leftward movement of sai carriage, said stop-member being moved to eflective position u on rotation of said rock-shaft.

3. The com ination with a sprin -propelled letter-feeding carriage, of a ta ulatmg mechanism including a key-operated rock-shaft, carriage-releasmg means operated by said rock-shaft, a friction strap anchored at its ends to the rear portion of the carriage, a stationary friction jaw for cooperation with said strap, and an arm extending upwardly from said rock-shaft and having a friction surface for pressing said strap against said stationary friction jaw when the carriage is released, said arm having an upward extension provided with a counter-stop for engagement with a column-stop upon the upper rear portion of the carriage, the column-stop being adjustable along a rack which is accessibly mounted upon the upper rear portion of the carriage.

4. In a typewriting machine, the combination with a spring-propelled carriage and a letter-spacing mechanism, of manually-operable instrumentalities effective for releasing said carriage from control of said letter-spacing mechanism, and devices for applying a braking force effective for restraining said carriage when released from said letter-s acing mechanism, said braking devices inc uding a yieldable brake-strap and two brakejaws to grip the strap, each jaw having a friction surface, a key-operated arm upon which one of said jaws is provided, and a carriagearresting stop upon said arm.

5. The combination with a letter-feeding typewriter-carriage and a tabulating mechanism, of a carriage-retarding device therefor, a counter-stop connected to be moved to effective position when the carriage is relased, a shouldered detachable column-stop co-operating with said counter-stop to arrest the carriage, a rack provided on said carriage for adjustably supporting said column-stop, and a bail hinged upon the carriage and including a locking bar extending along said rack to engage the shoulder on the column-stop, said rack, column-stop and locking bar being mounted on the upper rear portion of the caraacessibie pcsi'rb'ifim and. said carriage rai sasing and retarding devices including a raclmhaf; @0211 which extends fipwayly carrying said countewsmp, said arm having frictien jaw, strap pressefl 8 W'B8Il said irictien jaw mammary riccion jaw 11pm: the m chi'w.

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