US1521408A - Typewriter - Google Patents

Description

nec. 30B 1924. 152mm S. A. THOMPSON TYPEWRITER Fileld March 17. 1924 fav/@MW TTURNEVS Limo m Patented Dec. 3), 1924.

UNTED STTES SAMUEL ALEXANDER THOMPSON, OF NEW YORK, N. Y.

TYPEWRITER.

Application filed March 17, 1924.

T all lwhom, t may concern.'

Be it known that l, SAMUEL'A. THOMP- soN, a citizen of the United States of America, and a resident of the city of New York, borough of lv/lanhattan, in the county and State of New York, have invented a new and Improved Typewriter, of which the following is a description.

My invention relates to typewriters of the l0 class employing a carriage adapted to have step-by-step movement along a track and adapted to be depressed for impressing a given type after the type-carrying element has been revolved to bring a particular type to a point to print by a depression of the carriage.

rThe specific object of the present invention is to improve typewriters of the indicated character in certain particulars, es-

20 pecially with reference to the manner of mounting the feed pawl and the holding dog and with respect to the spring arrangement employed in association with the friction plate forming part cf the carriage for v5 preventing undue movement of the carriage along the track.

Reference is to 'be had to the accompanying drawings forming a part of this specification, it being understood that the drawings are merely illustrative of one example of the invention.

Figure 1 is a plan View of, a typewriter embodying my invent-ion showing the same partly broken away and in section;

Figure 2 is a transverse vertical section asindicated by the line 2-2, Figure 1;

Figure 3 is an inverted plan view of the depressible carriage;

Figure 1 is a detail in transverse vertical section given to show the holding dog and its spring;

Figure 5 is a section as indicated by the line 5 5, Figure 1.

Figure 6 is a cle-tail in transverse vertical section approximately in the plane 6 6, Figure 1.

In the illustrated example of my invention the numeral 10 indicates a foundation board or base at the front of which is shown a shaft 11 carrying paper feed rollers 12 said shaft having heads 18 for the manual turning of the shaft. A coacting shaft 15 is disposed beneath shaft 11 and has rollers 14 coacting with the rollers 12 to feed the Serial No. 699,882.

paper. An indicating strip 16 bearing a proper system of numerals is shown. A track 17 is shown the material of which along an edge thereof is returned as at 18. A carriage 19 is adapted to travel along the track 17 and has an end returned in U-shape as at 20 to lie alongside the returned edge 18.l Said carriage also has a strip 21 engaging the returned edge 18 at the inner side. The track 17 has a longitudinal rack 22 and coacting with the track are a feed pawl 23 and a friction dog 24 subject to retractile springs 25. All of the parts referred to are in general known except that the pawl 23 and friction dog 2&1 in accordance with my present invention are mounted in a given manner, as next described, and the springs of friction plate 21 are improved.

In the bottom of the carriage 19 openings 26 are formed and said pawl 28 and dog 24; have lugs 27 the terminals of which are outturned above the bottom of the carriage 19 as at 28. lt will be seen that the lugs 27 and their out-turned terminals 28 retain the pawl 28 and friction dog 24 in engagement with the plate 19 rwithout a positive pivot on a definite center. The purpose served is that flexibility is obtained in permitting the pawl and dog to accommodate themselves to the depression and rising of the carriage in printing and the exact register with the rack teeth otherwise necessary is avoided, the proper engagen'ient with the rack being insured in giving freedom to the pawl and dog to engage the teeth of the rack and to respond to the depressing and rising movements of the carriage.

The friction plate 21 as in practice in the typewriter to which my invention particularly relates, is under the influence of springs 29 holding it in contact with the inner side of the return portion 18 of track v17. In accordance with the present invention the springs 29, as best seen in Figure 6, are secured at one end to said plate 21 as at 30. The bottom plate 19 of the carriage has a slot 31 through which the springs 29 pass and the ends of said springs opposite the fastening at 80 are secured to lugs 32 on the bottom plate 19. The arrangement results in an effective action of the springs 29 in holding the friction plate 21 in effective contact with the returned portion 18 of the claim 1. In a typewriter of the class described, a track,a carriage adapted to travel on the track and adapted to be depressedr for printing, a friction plate engaging the track, and springs to maintain saidl plate in ric-V tional Contact Withthe track, the bottom plate 'of the'V carriage having a slot therein and said springs being secured at one end t0 the 'friction plate beneath'the bcttom of the carriage and passing through said slots, theoppo'site ends of said springs being secured to said bottom plate of the carriage.

2. In a typewriter of the class described,

a track, a carriage adapted to travel on said track and to be depressedl for pr1nt1nga rack on said track, a feed pawl on the carriage engageable'wvith said track, a fric-Y l y betteln of the carriage having vertical openings therein, and lugs 0n said paWl and dog, sad lugsextending'upwardly through said Openings in the bottom plate and Offset laterally at their terminals, said lugs having tree playin said openino's to permit the pawl and dog to accommcc ate themselves to the depressing movement v or the carriage and effectively Vco-act With the track.

SAMUEL ALEXANDER. THOMPSON

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