US2366023A - Typewriting machine - Google Patents

Description

Dec. 26, 1944. G. F. HANDLEY TYPEWRITING MACHINE Original Filed June 19, 1942 Patentel Dec. 26, 1944 George' F. Handley, deceased, late of Glendale,

N. Y., by Matilda J. Handley, executrin Yonkers, N. `Y., assignor to Royal Typewriter Company, Inc., ,New New York York, N. Y., a corporation of original application June 19, 1942, .serial No. 447,701. Divided and this 'application March 24, 1943. serial No. 480,368 t 6' Claims.

\ This invention relates to typewriting machines and more 4particularly to vmechanism for back spacing a typewriter carriage, that is moving the carriage reversely to the direction of letter spacing movement adistance corresponding exactly `to a predetermined number of letter space increments.

rIhis application is a division' of copending application Serial Number 447,701 filed June 19, 1942. y

Telegraphic messages usually are typed with wider than usual type faces and the step-by-step carriage movements `consequently Lare longer than in standard or portable typewriters equipped with the more Acommon sizes of type faces. In adapting a portable typewriter for writing with large type faces and relatively large feed lmovement steps there has been difficulty in properly positioning the carriage at its line starting position because of a tendency of the carriage to move back a step to the left after having been brought up against the center stop and then released. One way of overcoming this diiiiculty is to provide a check pawl for preventing reverse rotation of the escapement wheel, but such a pawl will interfere with the operation of back spacing mechanism of the kind in which the back spacing is effected by rotating the escapement wheel reversely. An object of the present invention is yto provide mechanism .including a back check pawl for preventing the undesirable leftward step movement of the carriage from its line starting position in combination with means responsive to actuation of the back spacing mechanism actuator for disabling the pawl so as to permit back spacing movementof the escapement wheel.

Other objects will become apparent from a reading of the following description, the appended claims, and the accompanying drawing, in which: Figure 1 is a fragmentary top View mainly in elevation but with some parts shown in section, illustrating escapement mechanism and back spacing mechanism Vassociated therewith, ,the parts being vshown in their inactive positions as when the typewriter carriage is at rest;

Figure 2 is a View similar to Figure 1 but with the` parts shown in 'the positions they occupy 'at the conclusion of a back spacing operation;

Figure 3is a section on the line 3 3 of Figure 2:

Figure 4 is a perspective view of a back spacer chick pawl;

Figure 5 is a perspective view of a part engageable with the back spacing check pawl for disabling the latter; and

Figure y6 is Ia perspective view `of a back spacing pawl.V

Mechanism embodying .theinvention may be incorporated in typewriting or like machines of var-` ious kinds. For the purposes of illustration the invention is disclosed as being combined with type-Writer escapement mechanism having the general organization of parts and features of the mechanism embodied .in the Royal Portable machine.

Because of the large width of the type faces and the resultant ,increased length Vof letter spacing step movements, the escapement wheel I is provided with only six teeth a, b, c, d, e, and f. The escapement wheel I is fast with a bushing 2 which is freely rotatable on a stud shaft '3 secured to a bracket 4 which is attached by screws 5 to plates 6 connecting carriage bottom rails C. A pinion 'Iv is mounted to rotate freely on the bushing 2 and meshes with `the usual carriage feed rack 8. A pawl 9 pivoted on the escapement wheel I is urged into engagement with the pinion I by a spring I0. The arrangement is such that the rack 8 tends vto rotate the pinion 'I 4'counterclockwise as viewed in Figures land 2, rotation of the pinion, however, being normally restrained by the pawl 9 carried by the escapement Wheel I which normally is held stationary by escapement dog mechanism which may be similar to that `disclosed in the patent to Handley No. 1,792,012 granted Feb* ruary l0, 1931. It includes an escapement frame I I pivotally mounted on the bracket 4 as at I 2 I2. The frame rII carries a relatively fixed dog I3.

AAinovable dog I4 is pivoted as at I5 on the frame Il and is formed with a stop I6 engageable with a stop arm l'I on the frame I I when the parts are in their positions of rest as shown in Figure 1. In this position the escapement pinion l and wheel I Aare being urged counterclockwise but rotation is prevented by engagement of the escapement Wheel tooth b with the ldog I4, the stop I6 of which is pressed against the frame stop I'I. The dog M is formed with heels I8 and I9 adapted to be engaged by a lever 20 pivoted at 2| 'on the frame II and urged against the heels by a spring.

22 anchored on a frame ear 23. The operation of this class of escapeinent dog mechanism is well knownand it' is believed unnecessary to describe it in detail.

The. back spacing mechanism per se is fundamentally similar to that disclosed in the Handley Patent No. 1,792,012 previously referred to. It includes an actuator slide 24 mounted to reciprocate in` ears 25 formed on the bracket 4. A back spacing pawl 2.6 pivoted on the slide member 24 as at 21 is urged counterclockwise as viewed in Figure 1 by a spring 28. Movement of the pawl by the spring is limited by engagement of a pawl ear 29 with the bottom of the actuator slide 24, and movement of the vpawl in the opposite direction is limited by engagement of a pawl ear 29a with the top of the slide 24. is formed with two teeth or noses 30 and 3| spaced longitudinally of the direction of movement of the slide 24.

In operation, mechanism including a key lever or the like (not shown) is actuated to move the slide 24 toward the right from its Figure 1 position. The pawl nose 30 will engage the escapement wheel tooth a and rotate the escapement wheel I reversely, thus also driving the escapement pinion 1 reversely so as to move the carriage rack 8 and carriage in the return direction. Because of the wide circumferential spacing of the escapement teeth, the pawl nose 30 would slip off the tooth a before back spacing equivalent to a full letter space increment could be effected. However, before the nose 30 can slip off the tooth a, the trailing pawl nose 3I will move in behind the tooth b and continue to move the escapement wheel reversely until the tooth c has moved above the escapement dogs I3 and I4 as shown in Figure 2. In this way the completion of a The .pawl 26 back lash or overthrow movement of the escapean ear 43 on the lever 39 normally holds the leback spacing movement equivalent to a letter spacing increment is assured.

'It has been found that due to the very great circumferential spacing of the escapement wheel teeth, manual sweep movement of the carriage in the return direction and up against the center stop (not s hown) followed by release of the carriage may result in movement of the carriage in the letter spacing direction, permitting the escapement wheel to move about one tooth thus feeding the carriage almost a complete letter space. This of course would result in an uneven spacing at the beginning of typing after the carriage had been returned. To overcome this difficulty means are provided for preventing reverse rotation of the escapement wheel I when the carriage is returned manually and for automatically permitting the escapement wheel to be rotated reversely when the back spacing mechanism is operated. In the form shown a check pawl 32 pivoted as at 33 on the right hand track plate 6 has a nose 34 normally positioned as shown in Figure 1 just behind an escapement wheelv tooth two removed from the tooth held by the escapement dog I4. A spring 35 interposed between the rearmost rail C and a tail 36 on the pawl 32 yieldably holds the pawl 32 in this position. During carriage letter spacing travel when the escapement wheel rotates counterclockwise as shown in Figure 1, the pawl 32 will be lifted by escapement wheel teeth so that they may pass freely under the pawl. However, during carriage return sweep movement the pawl 32 will hold the escapement wheel I against reverse rotation, movement of the carriage being permitted by the freedom of the escapement pinion 1 to move reversely while the escapement wheel is held stationary. I

When the back spacingmechanism is operated, the check pawl 32 must be disabled or rendered ineifective so as to permit the escapement wheel I to rotate reversely (clockwise as viewed in Figure 1). The check pawl 32 is formed with a cam 31 which is engageable with a part 38 carried by the back spacing pawl 26. Normally the part 38 simply supports the cam 31 Land back check pawl 32 in the position shown in Figure 1, but when ver in its inoperative position as shown in Figure 1, wherein the hooked end 4I is held against a portion of the bracket 4. Toward the end of a back spacing movement the ear 29 on the back spacing pawl 26 engages a tail 44 on the lever 39 so as to rock the lever against the urge of the spring 42 and bring the hooked end 4I into locking engagement with the escapement pinion 1.

The mechanism disclosed herein embodies the invention in the form now preferred, but it will be understood that changes may be made without departing from the invention as defined in the appended claims.

What is claimed is:

1. In back spacing mechanism for typewriting and like machines, escapement mechanism including an escapement wheel and means for controlling advancing rotation of said wheel; back spacing actuator means for rotating the escapement wheel reversely; a back check element for normally preventing reverse rotation of said escapement wheel; and means for rendering said back check element ineffective to thereby permit reverse rotation of said escapement wheel by said actuator means.

2. In back spacing mechanism for typewriting and like machines, escapement mechanism including an escapement wheel and means for con trolling advancing rotation of saidv wheel; back spacing actuator means for rotating the escapement wheel reversely; aback check element for normally preventing reverse rotation of said escapement wheel; and means responsive to operation of said back spacing actuator means for rendering said back check element ineffective to thereby permit reverse rotation of said escapement wheel by said actuator means.

3. In back spacing mechanism for typewriting or like machines, escapement mechanism including an escapement wheel and dog means for controlling advancing rotation of said wheel; back spacing actuator means engageable with said escapement wheel for rotating the latter reversely; a back check pawl for normally preventing reverse rotation of said escapement wheel; and means operable by said actuator means for rendering said back check pawl ineffective when said actuator means is operated.

4. In back spacing mechanism for typewriting or like machines, escapement mechanism including an escapement wheel and dog means for controlling advancing rotation of said wheel; back spacing actuator means e'ngageable with said escapement wheel for rotating the latter reversely; a back check pawl for normally preventing reverse rotation of said escapement wheel; a cam device on said back check pawl; and a part mov- 2,366,023 able during operation of said actuator means for engaging said cam device and moving said paWl out of. operative relationship to said escapement wheel. 'l

5. In back spacing mechanism for typewriting or like machines, escapement mechanism including an escapement Wheel and dog means for controlling advancing rotation of said Wheel; an

escapement pinion; a feed rack vengaging said p nion; a ratchet drive connection between said pinion and said Wheel for rotating said pinion reversely When said wheel is rotated reversely; back spacing means 4for rotating said wheel reversely; a back check paWl for normally prevent-r ing reverse rotation of said Wheel; and means operable by said back spacing means for rendering said back check pawl ineiiective when said back spacing means is operated.

6. In a typewriter or like machine, a frame; a carriage mounted to'travel thereon; a carriage feed rack; a toothed escapement wheel; an escapement pinion rotatable with said escapement Wheel and engageable with said rack; dog means cooperable with the teeth of said escapement wheel; back spacing actuator means engageable with the teeth of said escapement wheel for rotating the latter reversely; a back cheek pawl normally engageable with the teeth of said escapement wheel for preventing reverse rotation of said escapement Wheel; and means operable by said actuator means for moving said back 'check pawl out of the path of the escapement wheel teeth When said actuator means is operated.

MATILDA J. HANDLEY,` Eecutrirc of George F. Handley, Dec/eased.

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