US3223220A

US3223220A - Typewriter having sliding universal member

Info

Publication number: US3223220A
Application number: US264843A
Authority: US
Inventors: Willis E Rexford
Original assignee: Louis Marx and Co Inc
Current assignee: Louis Marx and Co Inc
Priority date: 1963-03-13
Filing date: 1963-03-13
Publication date: 1965-12-14
Anticipated expiration: 1982-12-14
Also published as: GB1053531A

Description

Dec. 14, 1965 w. E. REXFORD TYPEWRITER HAVING SLIDING UNIVERSAL MEMBER l0 Sheets-Sheet 1 Filed March 13, 1965 W 4 a w INVENTOR. Mzz/s f. ZFEXF'ORD Dec. 14, 1965 w. E. REXFORD TYFEWRITER HAVING SLIDING UNIVERSAL MEMBER 10 Sheets-Sheet 2 Filed March 13, 1963 INVENTOR 44/5 PEXFa/PD Dec. 14, 1965 w. REXFORD 3,223,220

TYPEWRITER HAVING SLIDING UNIVERSAL MEMBER Filed March 13, 1963 10 Sheets-Sheet 5 INVENTOR. M405 5. PEXFa/PD Dec. 14, 1965 w. E. REXFORD TYPEWRITER HAVING SLIDING UNIVERSAL MEMBER 10 Sheets-Sheet 4 Filed March 13, 1963 INVENTOR. M405 E. Fax/ amp Dec. 14, 1965 w. E. FEEXFORD TYPEWRITER HAVING SLIDING UNIVERSAL MEMBER l0 Sheets-Sheet 5 Filed March 15, 1963 Dec. 14, 1965 w. E. REXFORD TYPE-WRITER HAVING SLIDING UNIVERSAL MEMBER Filed March 13, 1963 10 Sheets-Sheet 6 i, If z Iii] .II II.

Dec. 14, 196 w. E. REXFORD TYPEWRITEH HAVING SLIDING UNIVERSAL MEMBER 10 Sheets-Sheet '7 Filed March 13, 1963 R 4 m %)r 3 a P 0 9 mm w 2 E %/2 a. m

Dec. 14, 1955 w. REXFQRD 3,223,220

TYPBWRITER HAVING SLIDING UNIVERSAL MEMBER Filed March 13, 1963 10 Sheets-Sheet 8 INVENTOR. Mu/s 'fzxraeo Dec. 14, 1965 w. E. REXFORD TYPEW'RITER HAVING SLIDING UNIVERSAL MEMBER 1Q Sheets-Sheet 9 Filed March 13, 1963 INVENTOR. 14/405 5. Pix/ 0;?!)

Dec. 14, 1965 w. E. REXFORD TYPEWRITER HAVING SLIDING UNIVERSAL MEMBER 10 Sheets-Sheet 10 Filed March 13, 1965 MW MFN INVENTOR M405 .5. FEXFaRD United States Patent Qfitice 3,223,220 Patented Dec. 14, 1965 3,223,220 TYPEWRITER HAVING SLIDING UNIVERSAL MEMBER Willis E. Rexford, Girard, Pa., assignor to Louis Marx & Co., 1116., New York, N.Y., a corporation of New York Filed Mar. 13, 1963, Ser. No. 264,843 6 Claims. (Cl. 19722) This invention relates to typewriters and, more particularly, to an improved portable typewriter characterized by simplicity and inexpensiveness of parts, ease of construction and assembly, and reliability in operation.

The primary object of the present invention is to provide a typewriter which, in addition to ease and simplicity of manufacture and assembly and ease and simplicity of operation, is characterized by improvements in various components such as the universal bar mechanism, the carriage escapement mechanism, the ribbon feed mechanism, the guiding means for the typing keys, the carriage biasing means, and the back spacing means.

Thus, a particular feature of the invention is a novel key guide or comb which is formed of a metal stamping having a plurality of slots extending transversely thereof and in longitudinally spaced relation. These slots act as guides not only for the typing keys but also for the pivoted levers supporting a space bar and for bell cranks interconnecting the typing keys to the type bars of the type basket.

The space bar levers, as well as the bell cranks, have portions projecting through slots in the upper surface of this comb, and a universal bar or rod is mounted to extend over this upper surface in somewhat spaced relation thereto and is arranged for bodily shifting sidewise. As a typing key is operated, or as the space bar is depressed, the universal bar is shifted bodily and this shifting of the universal bar controls operation of various parts of the typewriter such as the ribbon feed and the carriage escapement mechanism. Furthermore, the bell cranks, the typing keys and the space bar levers are easily inserted into the guide comb, thus contributing to the simplicity and efiiciency of assembly of the parts.

The novel construction and design of the carriage escapement mechanism provides a positive two-step advance of the carriage. The escapement mechanism includes an oscillatably mounted pawl mechanism cooperating with a rack secured to the carriage, and this rack has associated therewith a pair of operating levers or handles by means of which it may be lifted out of operative relation with the pawl mechanism so that the carriage may be readily and easily positioned at any place along its path or" travel. The pawl mechanism is also utilized as a novel means for raising the ribbon into proper position for engagement by a type bar, while maintaining the ribbon otherwise lowered so as to expose the typed material to view. For this purpose, a spring finger, such as a spring wire, projects from the pawl mechanism and is freely engaged through an aperture in a ribbon guide mounted for substantially vertical sliding movement.

The novel means for biasing the carriage assembly in one direction comprises a relatively elongated coil spring having one end secured to the carriage and its opposite end secured to a fixed part of the typewriter, with the spring extending around a pulley mounted adjacent one side of the typewriter. This biasing means provides a smooth movement of the carriage to the left during typing.

The novel ribbon feeding means includes a sheet metal stamping which is in the form of an elongated angle connected to the universal bar and being formed with rack teeth engageable with a pawl. The sheet metal rack member rests freely by gravity over the pawl and is moved in one direction, by operation of the universal bar, to operate the pawl and then slides freely back over the pawl teeth during reverse motion of the universal bar. Rotation of the pawl, through gearing and worms, rotates, selectively, one or the other of the shafts to which the ribbon spools are keyed.

A novel back spacing means is provided which includes two sets of linkages, one extending along one side of the typewriter and the other extending along the rear of the typewriter, these two sets of linkages being operatively interconnected in a novel manner. The linkage extending along the back of the typewriter is connected with the carriage escapement mechanism in a novel manner to eiiect back spacing responsive to operation of a back space key.

For an understanding of the principles of the invention, reference is made to the following description of a typical embodiment thereof as illustrated in the accompanying drawings. In the drawings:

FIG. 1 is a plan view, partly broken away, of a typewriter embodying the invention;

FIG. 2 is a longitudinal vertical sectional view through the typewriter shown in FIG. 1;

FIG. 3 is a horizontal sectional View taken on the line 33 of FIG. 2;

FIG. 4 is a vertical sectional view taken on the line 4-4 of FIG. 3;

FIG. 5 is a view corresponding to a portion of FIG. 2, but illustrating the parts in a different position;

FIG. 6 is a partial vertical sectional view taken on the line 66 of FIG. 3 and illustrating the ribbon feed shifting means;

FIG. 7 is an exploded partial perspective view of a ratchet means associated with the ribbon feed;

FIG. 8 is a partial vertical sectional view, taken on the line 88 of FIG. 3 and illustrating the operation of the universal bar by the space key;

FIG. 9 is a rear elevation view, partly in section, illustrating the carriage advancing mechanism;

FIG. 10 is a partial elevational view, partially in section, illustrating the escapement mechanism for the carriage;

FIG. 11 is a horizontal sectional view taken on the line 11-11 of FIG. 10;

FIGS. 12 and 13 are sectional views taken on the lines 1212 and 13-13, respectively, of FIG. 10;

FIG. 14 is a view of a portion of FIG. 12, but illustrating the escapement mechanism in a different position;

FIG. 15 is a sectional view taken on the line 1515 of FIG. 14;

FIG. 16 is an exploded perspective view of the escapement mechanism for the carriage;

FIG. 17 is an exploded perspective view of the guide comb and the association of the keys with the universal bar;

FIG. 18 is a partial side elevational view, partly in section, of a modified form of the typewriter shown in FIGS. 1 through 17 and including a back spacing arrangement;

FIG. 19 is a partial side elevational view, partly in section and with parts omitted, illustrating part of the linkage of the back spacing mechanism in an operated position;

FIG. 20 is a partial vertical sectional view taken on the line 2020 of FIG. 18 and illustrating further components of the back spacing linkage;

FIG. 21 is a view similar to FIG. 20 but illustrating the parts in an operated position; and

FIG. 22 is a partial horizontal sectional view of the typewriter shown in FIGS. 18 thruogh 21, taken on the line 22-22 of FIG. 20.

Support base and bracket assembly Referring to FIGS. 1 through 5, 8 and 9, the typewriter includes a support base 20 which may be a sheet metal stamping, and which is formed with an upstanding peripheral rim 21 and provided with support feet 22. Adjacent the keyboard, base 20 is formed with a relatively large cutout 23 conforming in general plan to the plan of the keyboard including the space bar. A shell or partial cover 19 for the typewriter may be secured to the rim 21 of base 20 in any desired manner, not forming any part of the invention.

Base 20 has secured thereto sheet metal brackets for supporting the various operating elements. There are two principal brackets, including a forward bracket, generally indicated at 25, and a rear bracket, or carriage guide bracket, generally indicated at 30.

Brackets

25 and 30 may be secured to base 20 in any desired manner as by riveting, spot welding, the use of twisted tongues, or the like.

Bracket 25 has the functions of supporting the universal bar or rod 100, which controls the ribbon feed and carriage escapement responsive to actuation of the typing keys or the space bar, and further supporting a pivot rod or axle 89 for the bell crank levers 75, operated by the individual keys, and for the space bar support arms or levers 81. T this end, bracket 25 includes a relatively elongated flat base 24 extending transversely of base 20 immediately to the rear of rimmed cutout 23. At each end of base portion 24 of bracket 25 there are upstanding arms 26 which are mirror copies of each other. Each arm 26 has a horizontally extending slot 27 near its upper end which is arranged to guidingly receive the universal bar 100. Somewhat below its mid-height portion, each arm 26 is formed with an aperture 28 arranged to receive an end of pivot rod 89 for the bell cranks and the space bar levers. Each upright arm 26 may have a substantially horizontal outturned upper end 29 which may be apertured.

Rear bracket 30 supports the carriage assembly, the type bar basket, the ribbon spools, the ribbon guides, and other parts cooperative with these components. Bracket 30 includes a generally channel shaped sheet metal member 31 (FIG. 2) extending transversely of base 20 adjacent the rear edge thereof, channel shaped member 31 having a base 32 spot welded or otherwise secured to support base 20, a rear wall 33, and a pair of front walls 34. Each front wall 34 extends inwardly a little less than one-third the length of channel member 31, and the inner edges of front walls 34 coincide with the ends of a rectangular notch 36 in channel base 32. Rear wall 33 is formed with a generally trapezoidal notch 37 extending downwardly from the upper edge thereof. Rear bracket 30 further includes a pair of generally vertical side members or walls 35 (FIG. 3) which are mirror copies of each other. The outer ends of

walls

33 and 34 are formed with tongues projecting therefrom which extend through correspondingly located slots in each side wall 35 and are twisted over to anchor the side walls to channel member 31.

Each side wall 35 of bracket 30 extends forward a substantial distance from channel member 31 and, rearwardly of this channel member, is formed, at its upper edge, with a laterally and vertically extending apertured ear 41. Below each ear 41, each side wall 35 has a bent tongue 42 projecting from its rear edge. The ear 41 on the left side wall 35, as viewed from the front of the typewriter, is used to rotatably mount a guide pulley 148 for a carriage return spring 145, and the bent tongue 42 on the right side wall 35 as utilized as an anchor for one end of spring 145, which spring is trained over pulley 148. Each side wall 35 further has a notch 43 in its upper edge, substantially centrally of channel 31, and a pair of ears 44 extend horizontally outwardly on either side of notch 43. The ears 44 on each of the side walls 35 serve to support the carriage assembly, and further act. in cooperation with notch 43, to form a bearing for a crank member 185 operating the carriage escapement mechanism.

Forwardly of channel member 31, each side wall 35 is formed, adjacent its lower edge, with a vertically extending slot 46 for a purpose to be described. A tongue 40 extends from the upper edge of each side wall 35, and has a forked upper end forming an outwardly opening notch which serves as a ribbon guide. Tongues 49 are twisted out of the general plane of each side wall 35 at an angle of about degrees, and it will be noted that the forward arm 39 of each ribbon guide extends a little above the rear arm 39' thereof. The upper portion of each wall 35 extends forwardly beyond ribbon guide 40, as indicated at 47, and each extension 47 is formed with a pair of vertically spaced and aligned outwardly extending apertured horizontal ears 48 which conjointly receive a drive spindle 115 for a ribbon spool 110. Forwardly of ears 48, each extension 47 is formed with a downwardly projecting and rearwardly opening hook 49 for a purpose to be described.

At a level somewhat above the center of slots 46, the inner edge of each front wall 34 of channel member 31 has a projecting car 51 (FIG. 2) which is bent forwardly to extend in a vertical plane and each car 51 is formed with a horizontal slot 52 for a purpose to be described. Also, the upper edge of each front wall 34 has a book 53 (FIG. 1) bent forwardly therefrom, likewise for a purpose to be described.

Type bar assembly The present invention features shifting between different characters by shifting the type bar basket. The type bar basket, which is generally indicated at St is essentially conventional except for the aforementioned shifting operation and the connection of the type bar levers in operative relation with the typewriter keys.

Basket includes a generally arcuately elongated casting 54 which has apertured cars 56 by means of which it may be secured by screws to a plate 57. Casting 54 is formed with outwardly opening radially extending slots 58 each of which receives the pivot end of a type bar lever 55. The pivot ends of levers are apertured to receive an arcuate pivot rod or shaft 59 which lies in a surface groove in casting 54 and is secured therein in any desired manner. Adjacent its pivot portion, each type bar lever 55 is formed with an apertured ear 61 for a purpose to be described. The outer end of each type bar lever has a type bar secured thereto, each type bar 60 being a casting carrying a pair of characters 62 spaced longitudinally thereof, with the casting being anchored over the free end of the associated level 55.

Mounting plate 57 for type basket 50 slides on a support plate 63 which has bent upper and lower ends. The upper end of support plate 63 is spot welded or otherwise securcd to front walls 34 of channel member 31, and the lower bent end of support plate 63 is spot Welded or otherwise secured to support base 20. Intermediate its ends, support bracket 63 is formed with a relatively large and substantially rectangular notch 64, and an angled ear 65 on the rear surface of plate 57 projects through notch 64 and rearwardly of support bracket 63. Mounting plate 57 is formed with a pair of spaced preferably circular apertures which are at the same horizontal level.

Plate 57 is guided for rectilinear movement along support bracket 63 in any suitable manner. The support bracket, and the entire type basket 50, are biased to an upper limit of movement by tension springs 66 connected between ears on the ends of plate 57 and the hooks or cars 53 on the front walls 34 of the channel member 31. The opposite ends of plate 57 are formed with apertured and forwardly directed cars 67 to each of which is pivotally connected one end of a yoke member 68. Each yoke member 68 is in the form of a strap which has its forward end bent laterally outwardly and then forwardly. The forward ends of yokes 68 are pivotally secured to vertical arms 26 of bracket by suitable means, such as rivets 69. The type bars are gravity biased to the position illustrated in FIG. 2 where they rest against a support 71 in the form of a generally arcuate rod having downturned ends engaged through aligned apertured cars 72 on the two yokes 63.

Keyboard mechanism The keyboard, generally indicated at 45, includes the typing keys 70, a space bar 80, and shift keys 85. As Will be noted from FIGS. 1, 2, 4, 5 and 8, the keys are arranged in three rows comprising a lower row, an intermediate row, and an upper row. Also, and with particular reference to FIG. 17, it will be noted that the keys are arranged in groups of three, with each key of a group differening in lever length from the adjacent keys. Thus, the longest keys 79A are used for the lower row, the intermediate length keys 70B are used for the intermediate row, and the shortest keys 70C are used for the upper row.

Each key is stamped from metal and is in the form of an angular strip of metal including a generally horizontal arm 73 and a generally vertical arm 74. There is one key 70 associated with each of the type bar levers 55, and the generally vertical arm 74 of each key has an operating head or button 76 secured on its upper end and having printed, or otherwise provided on its face, the characters of the associated type bar 60.

Each horizontal arm 73 has a reduced inner end 77 for a purpose to be described. Furthermore, each key 70 is formed with an aperture, with the apertures being located diflerently in each of the keys 7 0A, 70B and 7 9C. In keys 70A, this aperture is located adjacent an enlargement 78A spaced substantially from vertical arm 74, and in keys 7013, the aperture is located adjacent an enlargement 78B (FIG. 17) which is much closer to vertical arm 74. In keys 70C, the aperture is located at the intersection of

arms

73 and 74.

Space bar 80 is a relatively elongated plastic element which is supported upon a pair of levers 81. Each lever 81 is a relatively elongated and substantially flat metal stamping having an upturned outer end receivable in a recess in space bar 80. In alignment with the lower row of keys 70A and their operating buttons 76, levers 81, which are mirror copies of each other, are off-set, as at 82, to provide clearance for the operating buttons 76 of adjacent key levers 79, particularly when these operating buttons are depressed. For a purpose to be described, adjacent the rearward end of each lever 81 there is an upstanding arm 83 which normally extends in a substantially vertical direction. The rear end of each lever 81 is formed with a downturned abutment 84 for a purpose to be described. Each lever 81 is provided with a cutout 81A (FIG. 8) receiving one end of a spring 81B which encircles a pivot rod 89 to urge the lever in a clockwise direction to its normal position, with abutment 84 acting as a stop.

There are a pair of shift levers 85, one at each end of keyboard 45. Each shift lever 85 is a relatively elongated stamped metal strip provided with a pair of operating buttons 86 adjacent its forward end, one operating button being aligned with the lower row of keys 70A and the other operating button being aligned with the intermediate row of keys 7GB. Keys 86 are plastic elements suitably labeled, stamped, or imprinted With the designation FIG. SHIFT, and these plastic buttons have recesses engaging upstanding arms on each lever 85. The inner end of each lever 85 is apertured at the location of vertical slots 46 in side Walls 35 of rear bracket 39. The purpose of this will be described hereinafter.

Each typing key is operatively connected to its associated type bar through the medium of a bell crank 75. These bell cranks, while otherwise identical in construc- 6 tion, have the lengths of their horizontal arms varied so that there are three groups of bell cranks. Bell cranks 75A are associated with the lower row of keys 70A, bell cranks 75B are associated with the intermediate row of keys 70B, and bell cranks 750 are associated with the upper row of typing keys 70C. Each bell crank includes a generally vertical arm 87 and a generally horizontal arm 88, and has a pivot aperture at the intersection of these arms. Vertical arms 87 of the bell cranks are substantially equal in length. However, bell cranks 75A have the shortest horizontal arms 88, bell cranks 75B have horizontal arms 88 of an intermediate length, and bell cranks 75C have horizontal arms 88, which are longer than the corresponding arms of bell cranks 75A and 75B. The forward end of each horizontal arm 88 is formed with an angularly off-set tongue 79 engageable loosely through the aperture of the associated key 70 so as to pivotally connect this arm to the associated key. It will be noted that, with each key 70 pivotally connected to the forward end of arm 88 of its associated bell crank lever 75, the lengths of horizontal arms 73 of the keys 70, rearwardly of the bell cranks 75, are equal to each other.

Guiding structure for keyboard elements The principal component of the guiding structure for the keyboard elements is What may be termed a key comb 99 shown in FIGS. 2, 3, 5, 8 and 17. This key comb is a formed and die cut stamping of sheet metal, which is bent or otherwise formed to provide a substantially horizontal and relatively wide front flange 91, a front wall 92, a top wall 93, a rear wall 94, and a relatively narrow rear flange 96. Front flange 91 is suitably anchored, in any desired manner, to base 24 of front bracket 25, for example by tongues projecting from base 24 through apertures in flange 91 and twisted to lock flange 91 to base 24. Rear flange 96 is similarly anchored to main support base 20 of the typewriter. This rear flange also forms an abutting surface for engagement with rear abutments 84 of space bar levers 81.

Comb 913 is suitably located by engagement of its rear wall 94 with a short upturned flange 24' along the rear edge of base 24 of front bracket 25.

Comb or guide is formed with a series of slots extending through front wall 92 and top wall 93, these slots 95, in the front wall portion, being Wide enough to receive each typing key 70 and its associated bell crank 75 and, in the top wall, being somewhat narrower so as to have sufficient clearance to receive only the upright arms 87 of bell cranks 75. Rear wall 94 is formed with slots 95A, each of which is aligned, fore and aft, with a slot 95, and slots 95A are of a width sufiicient to receive, with clearance, horizontal arms 73 of levers 70. Front wall 92 extends vertically, then slopes forwardly and outwardly, and then has a short vertical section joined to top wall 93. Rear wall 94 lies in a single plane.

At locations laterally of the typewriter corresponding to the lateral locations of vertical arms 83 of space bar levers 81, comb top wall 93 is formed with short slots 97. Just a short distance laterally of each of the slots 97, front wall 92 of comb 90 is formed with a pair of slots 98 which are somewhat wider than

slots

95 and 95A. Also, rear wall 94 is formed with slots 98A which are aligned, fore and aft, with slots 98 and which havelfiibstantially the same width as slots 98.

Slots

98 and 98A are sufliciently wide to permit the passage, with clearance, of a key lever arm 73, a bell crank arm 88, and a space bar lever 81. Each end of front wall 92 extends somewhat beyond the corresponding ends of top wall 93 and rear wall 94, and these extended portions are reduced in height and formed with upwardly opening slots 99 for receiving shift levers 85.

In assembling the keyboard levers to the comb, bell cranks 75 are inserted from the front into the comb and space bar levers 81 are likewise inserted from the front '2 through the comb. Pivot rod 89 is then inserted through holes 28 in arms 26 of front bracket 25 and through the pivot apertures in bell cranks 75 and in shift levers 85, rod 89 being held in position as by swaging or bending its ends outside arms 26 of bracket 25. When this has been effected, vertical arms 87 of hell cranks 75 will extend substantially above top wall 93 of key comb 90, as will also vertical arms 83 of the two space bar levers 81.

The guiding means for the keyboard levers further includes a guiding element 101 engageable with reduced rear ends 77 of type key levers 70 and also having a guiding relation with shift levers 85. Referring to FIGS. 2, 3, and 17, rear lever guide 101 is an angular cross section member formed of sheet metal and having its base suitably anchored to main support base 20. Guide 101 may be suitably positioned fore and aft to the base by engagement of its vertical wall with tabs 102 struck up from base 20. The vertical leg of guide 101 is formed with a series of vertically extending and relatively short closed slots 103, each aligned with a type bar lever portion 73 and each having reduced end 77 of the type bar lever extending thereinto. Adjacent each end, the vertically extending rear leg of guide 101, is formed with an upwardly opening slot 104 each of which serves as a rear guide for a shift lever 85.

The typing keys 70 are biased to the upper position, or clockwise as viewed in FIG. 2, by any suitable means. Shown by way of example is a rubber spring device 105 which forms the subject matter of copending application Serial No. 264,937, filed March 13, 1963, by Shigeaki Kuramochi, now Patent No. 3,197,011, issued July 27, 1965. However, other types of spring biasing means may be used for the typing keys 70. Briefly described, rubber spring device 105 comprises a channel 106 having its: base suitably anchored to main support base 20 and located between comb 90 and rear guide member 101. Channel 106 is formed with a series of upwardly opening slots 107, each receiving one of the typing keys 70 in guiding relation. A substantially rectangular and relatively elongated strip of rubber, such as foam rubber, is disposed in channel 106 and extends somewhat above the upper edge thereof so that the several typing keys 75 will bear thereagainst while having guiding relation in slots 107. The shift levers pivot about the upper edges of tabs 109 struck up from base 20 and lying against the forward outer surface of channel 106 adjacent each end thereof. Tabs 109 extend somewhat above the upper edge of channel 106. Space bar 80 is biased in an upward direction by means of coil springs 101 having a turn embracing pivot rod 89 and having one leg engaged through a slot 98A and a second leg hooked into a notch 102 in the undersurface of each space bar lever 81. This is clearly illustrated in FIG. 8.

Interconnection 0 the keyboard levers t0 the operating parts of the typewriter Referring to FIGS. 2 and 5, for the purpose of operating a type bar 60 each time a key 70 is operated, each bell crank 75 is connected by a wire 113 to aperture 61 of the associated type bar lever 55. For this purpose, wire 113 may have a hooked end engaged in aperture 61 and an angularly off-set end engaged through the aperture at the upper end of the vertical arm of the associated bell crank.

As previously stated, the type basket is biased upwardly by springs 66 engaged between tabs 53 on rear bracket 34 and ears on type bar basket mounting plate 57. Shifting between lower case and upper case characters is effected by lowering the type bar basket rather than by raising the carriage assembly. As previously mentioned, each shift lever 85 has an aperture at its rear end substantially aligned with vertically extending slots 46 in the end plates of the rear bracket. Each shift lever 85 has associated therewith a rod 114, and each rod 114 extends through the aperture in the associated shift lever 85, through the adjacent vertically elongated slot 46, and through the horizontally elongated slot 52 in the nearer car 51 of rear bracket 30. The inner ends of rods 114 are engaged in the respective apertures in ear on plate 57. When either shift lever is operated, it is swung in a counterclockwise direction, as viewed in FIGS. 4 and 5, to move the outer end of its associated rod 114 upwardly in the adjacent vertically extending slot 46. The inner portion of each rod 114 thereupon moves forwardly in horizontal slot 52 in ear 51, and at the same time downwardly, to move ear 65, and thus mounting plate 57, downwardly. A tension spring 116 is connected at one end to ear 65 and at the other end to an upstruck ear of rear bracket 30.

The operation of feeding the ribbon and advancing the carriage, responsive to operation of a typing key or the space bar, is effected by a universal rod or bar 100. Rod 100 extends lengthwise of forward bracket 25, with its ends projecting through horizontal slots 27, suitable means being provided to prevent displacement of rod 100 from these slots. Slots 27 support rod 100 so that it is positioned slightly above upper wall 93 of comb 50 and, in a manner to be described, rod 100 is biased into engagement with vertical arms 87 of bell cranks 75 and with vertical arm 83 of each of the space bar levers 81. Each time a key is depressed, its associated bell crank is rocked counterclockwise, with the key 70, and particularly the horizontal arm 73 thereof, sliding rearwaro'ly as tab 79 on the bell crank lever moves downwardly and rearwardly. Also, each time space bar 80 is depressed, the upwardly extending arms 83 of its support levers move in a counterclockwise direction. Each of these movements of a bell crank or of the arms 83 advances universal rod or bar parallel to itself in a direction forwardly of the typewriter. This bodily sidewise reciprocation of universal bar or rod 100 is used to effect such actions as step-by-step advancing of the ribbon and operation of the escapement mechanism for the carriage, as will be described more fully hereinafter.

Ribbon feeding and guiding mechanism Referring to FIGS. 1, 2, 3, 4 and 5, ribbon spools or reels 110, are disengageably keyed to shafts which are rotatably supported in cars 48 of the side walls of rear bracket 30, each shaft being swaged or the like above the upper ear 48 to maintain the shaft against downward displacement. A gear 117 is secured on the lower end of each shaft and meshes with a respective worm 118 on a ribbon feed control shaft or driving 120. Shaft 120 is mounted for horizontal reciprocation in the horizontal slots formed by hooked ends 4? of the side parts of rear bracket 30. Each worm 118 is formed by coiling a short piece of wire about shaft 120, with the convolutions of the coils spaced to receive the teeth the gears 117, and this wire is soldered or brazed at at least one end to shaft 120 so as to retain the worm against displacement axially of shaft 120. Shaft 120 is formed with an operating handle 121 at one end thereof.

Shaft 120 is selectively shiftable to engage either worm 118 with the associated gear 117, and is arranged to be retained in the adjusted position. For this purpose, an inverted U-shaped bracket 122 has outwardly projecting ears 123 which are anchored to main support base 20 as by having tabs, struck from such base, extended through slots in ears 123 and twisted to lock these ears to base 20. Bracket 122 is arranged somewhat laterally outwardly of the adjacent end of shaft 115. A leaf spring 124 is anchored to the upper surface of bracket 122 and has a V-shaped deformation 119 adjacent its free end. Spring 124 bears against shaft 120 so that the shaft may be locked either inwardly or outwardly of deformation 119.

Shaft 120, in its ribbon feed switching action, operates as follows. Assuming that shaft 120 is moved to the position shown in FIGS. 3 and 6 wherein it is inwardly of deformation 119 of spring 124, right-hand worm 118, as viewed looking from the front of the typewriter, will be engaged with the associated gear 117 so that the shaft 115 at the right side of the typewriter, again looking from the front, will be rotated upon rotation of shaft 120. Left worm gear 118 will be disengaged from its associated gear 117 so that the left ribbon spool shaft 115 is free to rotate. To shift the ribbon feed, knob 121 is moved forwardly from the position shown in FIGS. 3 and 6. During this forward movement, shaft 120 tends to pivot about the axis of the right-hand ribbon spool shaft 115, due to engagement of right-hand worm 118 with right-hand gear 117. This swings left-hand worm 118 into engagement with left-hand gear 117 as shaft 120 engages V-shaped deformation 119. As shaft 121 snaps past this deformation and is re-engaged with spring 124 outwardly of the deformation, left-hand worm 113 remains in engagement with left-hand gear 117 to act as a pivot for shaft 121), and right-hand worm 118 is disengaged from right-hand gear 117. Right-hand shaft 115 is thereupon free to rotate, whereas left-hand shaft 115 will be rotated only when shaft 120 is rotated in a manner to be described.

The rotation of shaft 120 is always in a clockwise direction, as viewed in FIGS. 4, and 6. Such rotation is effected by a pawl or rack 125 engageable with a ratchet gear 130 secured on shaft 120. As best seen in the perspective view of FIG. 7, pawl or rack 125 is a formed stamping of relatively light gauge sheet metal. The major portion of the pawl is angular in cross section to provide a generally vertical leg having an elongated slot 126 of a width somewhat greater than the diameter of shaft 120. An arm 127 extends angularly upwardly and forwardly from this vertical wall and is formed with an aperture at its free end. The horizontal leg of the pawl or rack 125 is formed with a series of rack teeth 128, which are tabs punched and bent out of the horizontal leg to extend downwardly and rearwardly. It will be noted that the teeth of gear 130 are substantially triangular with the radial edges facing toward teeth 128 of pawl 125.

Pawl or rack 125 is operated by universal bar 100 which is extended through the aperture in the outer end of arm 127. When universal bar 160 is moved forwardly, teeth 128 of the pawl ride over the teeth of gear 131?, due to engagement with the sloping surfaces thereof as seen, for example, in FIG. 4. The clearance between the horizontal edges of slot 126 and shaft 120 is at least sufiicient to provide for such overriding movement. When universal bar or rod 160 is returned to its rest position, pawl 125 is moved rearwardly. During this movement of pawl 125, teeth 128 engage the radial faces of the teeth of gear 136 to rotate this gear, and thus shaft 124), counterclockwise. Through one of the worms 118, one of the gears 117 is rotated and thus imparts a rotation to its connected shaft 115 to take up the ribbon. Felt washers 137 beneath each spool 110 act as friction brakes on the associated spool.

Between the two spools 110, ribbon 129 is guided through the slots in arms 40 and through a vertically movable ribbon guide 135. Ribbon guide 135 is slidably mounted, for vertical movement, upon mounting plate 57 for the type bar basket. In a conventional manner, mounting plate 57 is formed with a pair of guide ears 131 for guiding the type bars into accurately centered position when a key 70 is struck, and a slot is formed extend ing downwardly from these ears. Ribbon guide 135 is formed with ribbon guiding fingers 132 through which the ribbon extends.

In the normally lower position of ribbon guide 135, the ribbon is displaced away from guide ears 131 so that the typed matter is visible. As a key 70, or space bar 80, is struck, ribbon guide 135 is moved upwardly so that ribbon 12? is positioned in the path of movement of a type bar 60 on a type bar lever 55. This position is shown in FIG. 2 of the drawing. Guide is simply a substantially fiat piece of sheet metal which engages the back or rear surface of mounting plate 57 for the type bar basket, and has ears 133 bent around each edge of plate 57 and overlying the front surface thereof. As best seen in FIGS. 2 and 5, plate 57 is formed with an elongated vertically extending slot 134, and guide 135 is formed with an aperture 136 aligned with this slot, both for a purpose to be described.

Carriage assembly Referring to FIGS. 1, 2, 5 and 9 through 15, the carriage assembly includes a fixed channel shaped track or guide 140 over which is telescoped an inverted channel shaped movable slide 150 constituting the carriage. The base of fixed track 140 is apertured adjacent each end so that it may be secured, by screws or the like, to horizontal ears 44 on each of the side walls of rear bracket 30. Each flange of track 140 is formed, substantially mid-way of its height, with an outwardly facing V-shaped recess 141 extending longitudinally thereof. correspondingly, the flanges of movable channel slide 150 are formed, intermediate their height, with an inwardly facing V-shaped recess 151 which extends longitudinally thereof, and each recess 151 is aligned with a recess 141. The facing recesses 141 and 151 receive ball bearing assemblies each comprising ball bearings 1 .2 with which may be associated a rectilinear retainer (not shown). Screws 152 (FIG. 1) are threaded through the inner flange of movable slide 150 and serve as abutments to limit relative longitudinal movement of slide 150 along track 140, these screws engaging, for example, the ends of the roller hearing retainers. By means of ball bearings 142, slide 150 and the elements supported thereby are freely movable longitudinally of track 144 For a purpose to be described, the base of track or carriage guide 1 .1 has a pair of apertured ears 143 struck out therefrom at longitudinally spaced locations, and between these ears there is a substantially rectangular aperture 144 out from the base. A bell 146 is mounted on the lower surface of the base of track 140 and, associated with this bell, is a spring biased trip hammer 147 which is arranged to be operated to ring bell 146 by a tab 153 on slide 159 as the latter nears the end of a line of type.

The carriage assembly, the elements of which are mounted upon the movable carriage 150, is biased to the left, as viewed from the front of the typewriter, so that under the control of the escapernent mechanism, the carriage assembly will step to the left each time a key 70 or space bar 81 is operated. The biasing means comprises a relatively elongated coil spring which has one end hooked to a lug 154 on the movable slide or carriage 150. A grooved pulley 148 is rotatably mounted in the left-hand apertured ear 41 extending from wall 35 of the rear bracket, and spring 145 is trained around pulley 148 and its opposite end is hooked to the lug 42 projecting from the right-hand end wall 35 of the rear bracket, as best seen in FIG. 9.

The base of movable slide has ears 156 extended from each end thereof and bent vertically upward. These ears are apertured in alignment with each other to receive the pivots for a cylindrical platen 155, and the outer ends of the ears are substantially circular and flanged to partially overlie the platen. A plastic knob 157 is secured to each end of the platen shaft for rotating the same to set and advance the paper. A coil spring 158 is engaged between the right-hand ear 156 and the right-hand knob 157 to act as a frictional lock to maintain platen in adjusted position.

A sheet metal paper guide 160 is provided, having a transversely arcuate portion closely embracing platen 155. Adjacent its forward edge, and at other locations if desired, guide 160 is formed with longitudinally extending slots 161 having ears adjacent each end rotatably supporting a small diameter rubber roller 162. These rollers 1 1 engage the paper and maintain it firmly engaged with platen 160. Intermediate its front and rear edges, paper .guide 168 is pivoted to ears 156 as by means of small tabs (not shown) projecting through apertures in ears 156. One or more springs 163, connected between lugs struck from the rear surface of paper guide 160 and lugs struck from the base of the slide 154), bias paper guide 160 in a clockwise direction, as viewed in FIG. 2, to maintain roller or rollers 162 in engagement with platen 155.

The upper rear edge of paper guide 160 is bent back on itself, as at 164, to form a bearing for the reentrant ends of a paper holding wire 165 which normally engages platen 155 a little bit forwardly of its uppermost point and extends therealong to guide a paper around the platen. A coil spring 166 (FIG. 1) biases paper wire 165 into engagement with platen 155. Reentrant edge 164 also forms an easy to use handle for manual operation to swing paper guide 160 counterclockwise, as viewed in FIG. 2, to allow insertion and adjustment of paper between platen 155 and paper guide 160'.

A bracket 149 is secured to the left ear 156 and has a horizontally extending apertured upper ear 159 which pivotally supports a horizontally swingable angle lever 170 utilized for step by step rotation of the platen and return of the carriage assembly to the right at the end of each line. Interengageable stops on ear 159 and lever 170 limit movement of lever 176 in one direction. A wire link 167 interconnects lever 176 to a pawl and ratchet mechanism, generally indicated at 168, for such step by step rotation of platen 155.

Escapement mechanism Referring to FIGS. 2, and 9 through 16, the escapement mechanism for the typewriter includes a rack 175 movable with slide 150 and cooperable with a pawl mechanism generally indicated at 188 and operated by movement of the universal bar or rod 100. In a manner to be described more specifically hereinafter, pawl mechanism 180 is oscillatably mounted in apertured ears 143 of track or carriage guide 140 and extends across rectangular aperture 144 in the base of track 140. Pawl mechanism 180 is oscillated by means of a crank 185 described more fully hereinafter, and crank 185 is connected to universal bar 160 by means of a pair of off-set links 171 each apertured at one end to receive bar 100 and at the other end to extend over the ends 183 of crank 185.

Links 171 are retained against displacement longitudinally of universal bar 18% by virtue of being inside of end walls 26 of front bracket 25. The rear ends of links 171 may be slipped over the ends of crank 185 and are retained from disengagement therefrom by means of ears 172 struck up from support base 28 and each located, with clearance, outwardly of a link 1711. As described hereinafter, the arrangement is such that each time universal bar 100 is moved sideways by operation of a key 70 or space bar 80, crank member 185 is oscillated and this actuates the escapement mechanism.

Escapement rack 175 is an essentially flat piece of meta-l having a base 176 formed with a reinforcing rib 177 therealong, as best seen in FIG. 12. A lip 178 is bent down along one edge of base 176 and formed with sawtooth ratchet teeth 190 whose left faces, as viewed from the front of the typewriter, are vertical and whose right faces are sloping. The opposite ends of rack 175 are bent upwardly, as at 173, and are outwardly off-set, the free ends of the upwardly bent portions 173 being provided with outwardly projecting thumb pieces 174. Ears 173 are pivoted to one ear 156 and the bracket 149, respectively, as indicated at 179. Thereby, the rack 175 may be swung counterclockwise, as viewed in FIG. 12, to disengage teeth 190 from pawl mechanism 180. However, a coil spring (not shown) operates on one ear 173 and rack 175 to bias rack 175 to the position indicated in solid lines in FIG. 12. For free movement of the carriage, one or the other of thumb pieces 174 is lifted and the rack mechanism is swung to the dotted line position of FIG. 12. By virtue of disengagement of teeth 190 from pawl mechanism 180, movable carriage slide may be moved freely relative to the fixed track 140, within the limits of movement.

As best seen in FIG. 9, escapement operating crank 185 is a relatively elongated circular cross section rod which is bent, adjacent each end, to form two rectangular U- shaped off-sets providing pivot axes 1.81 which lie in and extend through the slots 43 between horizontal ears 44 of rear bracket 30. These two offsets provide a relatively elongated central crank section 182 extending between the two off-sets, and crank ends 183 which are engaged through apertures in the rear ends of links 170. Central crank section 182 serves to oscillate pawl mechanism 188 each time universal bar or rod is moved forwardly and returned.

Referring to FIGS. 9 through 16, pawl mechanism 188 includes a generally channel shaped bracket 184 having a base 186 and

flanges

187 and 188. The normally vertical free edges of

flanges

187 and 188 have ears which are extendible through slots in a generally channel shaped cover plate 189, arranged to embrace

flanges

187 and 188, with these cars being bent over to secure cover plate 189 to bracket 184.

Flanges

187 and 188 are formed with aligned apertures 191 which receive a bolt and nut assembly 192 extending through the apertures in ears 143 and serving as a pivot for oscillation of pawl mechanism 188. A spacer 193 surrounds the bolt and nut assembly 192 to space flange 188 from the adjacent ear 143, and a coil spring 194 surrounds the bolt assembly between flange 187 and the adjacent ear 143 to space this flange from the adjacent ear and to bias pawl mechanism to the left, as viewed in FIG. 10. Flange 188 is formed with a downwardly opening vertical slot 196 in alignment with pivot 192 and arranged to engage central portion 182 of escapement crank 185. The upper end of flange 188 has extending therefrom an ear which has a perpendicular face toward base 186 and a curved face toward cover 189. For reference purposes, ear 195 will be referred to as the fixed pawl or first pawl.

Base 186 of bracket 184 is formed with a horizontal slot 197 adjacent its upper end receiving a headed pivot 198. Pivot 198 serves as an oscillation pivot for a movable pawl carrier plate 200 which is generally triangular. An ear 199 bent from the upper edge of base 186 limits movement of carrier plate 290 in a counterclockwise direction as viewed in FIG. 16. Carrier plate 200 is formed with a horizontal arm 261 extending through vertical slot 202 at the intersection of base 186 and flange 188. A second horizontal arm 283 is bent inwardly from the plate 200 and is formed with an anchor for a tension spring 204. The other end of spring 204 is anchored to the operating rod or wire 285 for the movable ribbon guide 135.

Wire 205 has an off-set end 206 anchored through an aperture in flange 188. The remainder of the rod is rectilinear and extends outwardly through an aperture 207 in cover plate 189 and through aperture 136 in ribbon gniide 135 and slot 134 in mounting or support plate for the type basket. Spring 204 biases carrier plate 200 in the counterclockwise direction.

Plate 200 has an upwardly extending projection 211 from which there is bent an ear 218, hereinafter referred to, for reference, as the movable pawl or second pawl. Pawl 210' extends parallel to fixed pawl 195. and is spaced therefrom, longitudinally of the carriage assembly, by a spacing slightly less than the distance between the vertical faces of three teeth 199. This is best illustrated in FIG. 10. Also, and as best seen in FIGS. 12 and 14, fixed pawl 195 and movable pawl 210 overlap each other a relatively small amount in a direction transversely of the carriage assembly.

Normally, pawl 210 is engaged with the vertical face of a tooth 190. When pawl mechanism 180 is rocked in a clockwise direction, as viewed in FIG. 12, fixed pawl 195 will be moved into position to engage the vertical face of a tooth 190 before movable pawl 210 disengages the vertical face of its associated tooth 190. Thus, there will be only a slight movement to the left of the carriage during such clockwise rocking of pawl mechanism 180. As the pawl mechanism is rocked back to the perpendicular position of FIG. 12, the less than 3-teeth spacing of the two pawls will result in movable pawl 210 being positioned in advance of the vertical face of the next tooth 190 to the right of that previously engaged and, as fixed pawl 195 disengages its tooth 190, the carriage will be moved to the left by an amount slightly less than the spacing between two adjacent teeth 19%, and will be stopped in this position by engagement of a tooth 196 by movable pawl 210.

It should be noted that the carriage assembly, including the pawl mechanism and associated parts, may be assembled as a unit before being placed on the typewriter. In placing the carriage assembly on the typewriter, it is merely necessary to align slot 196 with central crank portion 182 of escapement crank 185, and then to secure track 141) to support ears 44. This greatly facilitates assembly of the typewriter, as all that is needed, following this operation, is to attach spring 145 at one end to hook 154, extend it around pulley 148, and attach the other end to hook 42.

Rsum of operation When a typing key 70 is depressed, its associated bell crank 75 is rocked counterclockwise, as viewed in FIG. 2. This will move universal bar or rod 100 to the left, as viewed in FIG. 2, along slots 27. The same action takes place whenever space bar 80 is depressed, as the upward extensions 83 of its levers 81 will likewise move universal bar 100 to the left in slots 27.

The movement of universal bar 180 to the left in slots 27 effects a number of operations. Through link 127 of ratchet 125, ratchet wheel 138 and shaft 120 are rotated counterclockwise, and one or the other worm gears 117 is rotated to rotate its associated shaft 115 and ribbon spool 110 to advance the ribbon.

The second operation occurs through the movement of links 171. This rocks escapement crank 185 which rocks pawl mechanism 180 clockwise as viewed in FIG. 12. Through wire 205, movable ribbon guide 135 is then elevated to the typing position for engagement by a type bar 60 of a type lever 55. Also, such clockwise rocking of escapement mechanism 180 disengages movable pawl 210 from its associated tooth 190 of rack 175 and engages fixed pawl 195 with a tooth, after a short movement of the rack to the left. Under the bias of a spring 212, connected between central portion 132 of escapement crank 185 and a rear portion of rear bracket 30, pawl mechanism 180 is biased to the position shown in solid lines in FIG. 12. Thus, as a key 70 or the space bar 80 is released, pawl mechanism 180 is biased back to its vertical position wherein fixed pawl 195 releases a tooth and movable pawl 210 engages the next adjacent tooth to the right of that previously engaged. The resultant counterclockwise rotation of escapement crank 185, through links 171, moves universal rod or bar 100' to the right in slots 27. In turn, the counterclockwise rotation of pawl mechanism 180, through wire 205, lowers movable ribbon guide 135.

As has been previously described, depression of either one of the shift levers through either one of its two operating buttons 86, lowers the type bar basket as a unit in order to type the upper case characters. Free movement of carriage 150 in either direction may be effected by grasping thumb pieces 174 of levers 173 and lifting them from the solid line position to the dotted line position of FIG. 12. This disengages rack teeth 190 from pawl mechansm 180 to provide for free longitudinal adjustment of the carriage assembly. A

change in direction of the ribbon feed can be effected readily by moving operating button 121 either forwardly or rearwardly, depending upon its initial position. This will disengage one worm 118 from its gear 117 and engage the other worm 118 with its gear 117. Furthermore, ready adjustment of the paper around the platen can be effected by swinging paper guide 160 clockwise, as viewed in FIG. 2, thereby releasing rollers 162 from the paper so that the latter may be readily adjusted.

FIGS. 18 through 22 illustrate the typewriter shown in FIGS. 1 through 17 as slightly modified to incorporate a back spacing mechanism. Referring first to FIGS. 18 and 19, a back space key lever 215 has its operating head 220 positioned adjacent the inner left-hand corner of keyboard 45, to the left of the inner or third row of typing keys 70C. Back space lever 215 is pivotally mounted upon left-hand upright arm 26 of bracket 25 which, for this purpose, is modified to receive a pivot 216, for lever 215, and a stop pin 217. Lever 215 is an essentially flat stamping of sheet metal, stamped to provide a forward angle portion 218 and a rear angle portion 219. Operating button or back space key 220 is set on the upwardly extending portion of forward angle section 218.

The rear end of the rear angle portion 219 carries a pivot pin and spacer arrangement 221 which is slidably engaged in a diagonal slot 222 in the forward end of what may be termed an intermediate side link or lever 225 which is pivoted, intermediate its ends, on an L-shaped bracket 223 secured to base 20 adjacent the left side thereof and just forwardly of rear bracket 30. Intermediate side lever 225 has a forward inwardly off-set portion 224 and a rearwardly extending arm 226, off-set portion 224 being formed with the slot 222. Side lever 225 is a flat metal stamping formed to have an upwardly off-set and rearwardly extending operating end 227.

Adjacent operating end 227 of lever or link 225, left side wall 35 of rear bracket 30 is formed with a vertically extending slot 228. Referring to FIGS. 20 through 22, adjacent left side wall 35 of bracket 30, the rear wall 33 thereof is apertured to receive a pivot pin 231 surrounded by a spacer 232 and pivotally mounting an engaging lever 230. Engaging lever 230 is an essentially fiat stamping of metal which is T-shape in plan including a stem 233 extending through slot 228 and having its outer end twisted, as at 234, to extend substantially horizontally and to engage beneath operating end 227 of intermediate side lever 225. Lever 230 is engaged by its pivot 231 at a pivot axis which is spaced somewhat above the junction of its stem 233 and its head 236. The upwardly extending portion of head 236 is notched, as at 237, to anchor one end of a tension spring 235.

A rack engaging and pushing lever 248 has its outer end pivotally secured to the lower extension of head 236 of lever 230, as indicated at 238. Lever 240 is generally L-shaped in elevation, and comprises a piece of sheet metal stamped and formed to provide a generally horizontal and relatively long arm 241 and a generally vertical arm 242. A flange 243 is bent inwardly at a right angle from the free outer edge of arm 242, and it will be noted that arm 242 has a bent portion 245 projecting upwardly through the aperture 244 in track formed by cutting and bending ear 143 from the base of the track. Flange 243 is continued part way along bent upper end 245 of arm 242. The other end of tension spring 235 is hooked into an aperture 246 in horizontal arm 241 of lever 240, this aperture being located substantially midway of the length of arm 241.

It will be noted that engaging and pushing lever 240 is freely pivotally mounted upon the lower end of head 236 of lever 230. Tension spring 235 tends to bias lever 240 clockwise and lever 230 counterclockwise. In the normal position of the parts, as illustrated in FIG. 20, bent portion 245 of arm 242 of lever 240 engages the bend line of ear 143, with finger 245 and a part'of flange 243 extending into aperture 244. In this position of the parts, there is a resistance to the clockwise rotation of lever 240 about its pivot 238, so that lever 2343 is biased counterclockwise, lifting end 227 of intermediate side lever 225 and, through the connected linkage, elevating operating key 220 of back space lever 215. The upper end of flange 243 is disposed somewhat beneath teeth 190 of rack 175.

When key 220 of back space lever 215 is depressed, this lever is swung clockwise, as viewed in FIGS. 18 and 19, to the position of FIG. 19. This swings intermediate side lever 225 counterclockwise so that operating end .227 thereof moves finger 234 of lever 230 downwardly in slot 228. This swings lever 230 clockwise from the position shown in FIG. 20 to the position shown in FIG. 21.

Due to the tension of spring 235, the first result of the clockwise movement of lever 230 is to move engaging'and push lever 240 clockwise with bent portion 245 of arm 242 of lever 240 sliding upwardly due to its angular relation with the intersection of ear 143 and the base of track 140. This moves flange 243 upwardly between a pair of teeth 190 of rack 175. After a very short movement, such upward movement is halted by engagement of the upper end of flange 243 with rack 175, so that lever 240 can no longer move clockwise.

Upon further movement of lever 230 clockwise, due to operating end 227 of intermediate side lever 225 moving downwardly, lever 240 is shifted bodily to the left, as viewed in FIGS. 20 and 21. During this motion, flange 243, in engagement with a perpendicular face of an adjacent tooth 190 of rack 175, moves rack 175 to the left a distance equivalent to about 1.5 times the spacing of teeth 190. Such motion is equivalent to a return motion of the carriage, so that pawl mechanism 180 will slip over the sloping surfaces of teeth 190. As back space key 220 is released, the parts are returned, under spring bias, to the positions shown in FIGS. 18 and 20, wherein flange 243 is disengaged from teeth 19%. Rack 175 is locked in its newly adjusted position by pawl mechanism 180, and there will be a very slight movement to the left of rack 175 until the rack teeth engage movable pawl 210 of pawl mechanism 180.

While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.

What is claimed is:

1. A typewriter comprising, in combination, a support base; a keyboard including typing key levers; a type bar basket; pivotally mounted bell cranks connecting respective typing key levers to respective type bars of said type bar basket; and guiding and spacing means for said typing key levers and said bell cranks; said guiding means including a comb extending transversely of said base, rearwardly of said keyboard; said base comprising a sheet of metal bent to form a forward wall extending upwardly of said base, a top wall extending substantially parallel to said base, and a rear wall extending downwardly from said top wall to said base; said front and top walls being formed with a plurality of slots equal in number to the number of typing key levers and to the number of associated bell cranks, said slots being closed end slots and extending upwardly in said front wall and rearwardly into said top wall; the portions of said slots in said front wall being wider than the portions thereof in said top wall; the portions of said slots in said front wall each receiving a typing key lever and one arm of its associated bell crank, with clearance; the portion of each slot in said top wall receiving, with clearance, the normally upwardly extending arm of a bell crank; said bell cranks being pivotally mounted on a shaft extending longitudinally through said comb and mounted in walls extending upwardly from the base at opposite ends of said comb, said walls at opposite ends of said comb being parallel to each other and each formed with a substantially horizontal slot, with the two slots being aligned; a rod extending longitudinally of said comb top wall and having its ends engaged through said slots, said rod being engaged with that arm of each bell crank which isconnected to a type bar; whereby, upon operation of a typing key lever, said rod will be displaced bodily along said slots while extending parallel to its original position; a carriage moveably mounted transversely of said base; escapernent mechanism controlling movement of said carriage in one direction transversely of said base; and linkage means inter-connecting both ends of said rod and said escapernent mechanism; said linkage means including a transversely pivoted elongated crank proximate to said escapernent mechanism and cooperating therewith, and a pair of links, each being connected, at opposite ends, to one end of said elongated crank and a corresponding end of said rod extending longitudinally of said comb.

2. For use in a typewriter having a frame, an escapernent mechanism comprising a sawtooth rack adapted to extend longitudinally of a carriage of the typewriter, and a pawl mechanism mounted for oscillation about an axis parallel to said rack, said pawl mechanism including a bracket pivoted to said frame on said axis parallel to said rack and having a first normally vertical wall extending perpendicular to said axis and a second normally vertical wall extending parallel to said axis; a first pawl projecting upwardly from said first wall for engagement with the teeth of said rack, and normally disengaged from said teeth; a carrier plate slideably mounted on said second wall and having projecting therefrom a second pawl normally in engagement with said sawteeth; said carrier plate being slideable in a direction parallel to said axis and including means cooperating with said bracket for limiting the sliding movement thereof to a distance approximating the distance between adjacent teeth, and spring biasing means acting on said carrier plate to normally urge said second pawl toward said first pawl; said pawls extending parallel to each other, and normal to the direction of movement of said rack, and said pawls extending into overlapping relation transversely of said rack whereby, as said second pawl is disengaged from said rack said first pawl will be moved into engagement with said rack, and as said first pawl is disengaged from said rack said second pawl will be moved into engagement with said rack; said pawls being spaced from each other, in a direction parallel to the travel of said rack.

3. A typewriter comprising, in combination, a frame including a support base; a keyboard including typing key levers; a carriage guide extending laterally of said base; a carriage displaceable along said guide; means biasing said carriage in one direction along said guide; an escapernent mechanism controlling stepwise displacement of said carriage in said one direction; a platen on said carriage; means operatively interconnecting said typing key levers and said escapernent mechanism whereby, responsive to each actuation of a typing key lever, said escapernent mechanism is operated to provide for stepped movement of said carriage along said guide under the influence of said biasing means; said escapernent mechanism comprising a sawtooth rack extending longitudinally of said carriage, and a pawl mechanism oscillatably mounted on said carriage guide for oscillation about an axis parallel to said rack; said pawl mechanism including a bracket pivoted to said frame on said axis parallel to said rack and having a first normally vertical wall extending perpendicular to said axis and a second normally vertical wall extending parallel to said axis; a first pawl projecting upwardly from said first wall for engagement with the teeth of said rack, and normally disengaged from said teeth; a carrier plate slideably mounted on said second wall and having projecting therefrom a second pawl normally in engagement with said sawteeth; said carrier plate being slideable in a direction parallel to said axis and including means cooperating with said bracket for limiting the sliding movement thereof to a distance approximating the distance between adjacent teeth, and spring biasing means acting on said carrier plate to normally urge said second pawl toward said first pawl; said pawls extending parallel to each other and normal to the direction of movement of said rack, and said pawls extending into overlapping relation transversely of said rack whereby, as said second pawl is disengaged from said rack said first pawl will be moved into engagement with said rack; said pawls being spaced from each other, in a direction parallel to the travel of said rack; whereby, as said pawl mechanism is oscillated in one direction responsive to a typing key lever actuation, said second pawl will disengage its engaged rack tooth and slide toward said first pawl under the urging of said spring biasing means, and said first pawl will move into the path or" a rack tooth to allow a slight movement of the carriage from right to left as viewed from the front of the typewriter and, as the typing key lever is released, the reverse oscillation of said pawl mechanism will move said second pawl into position to engage the tooth adjacent the one previously engaged and, as said first pawl is disengaged from said rack, said carriage and said second pawl will move the balance of the distance between two rack teeth from right to left in response to said carriage biasing means.

4. A typewriter comprising, in combination, a support base; a keyboard including typing key levers; a type bar basket; pivotally mounted bell cranks connecting respective typing key levers to respective type bars of said type bar basket; guiding and spacing means for said typing key levers and said bell cranks, said guiding and spacing means including an elongated comb extending transversely of said base rearwardly of said keyboard and said comb having a pair of opposed end walls parallel to each other and respectively formed with substantially horizontal slots which are in alignment with each other; a carriage movable transversely of said base; escapement mechanism controlling movement of said carriage in one direction transversely of said base; and an assembly for actuating said escapement mechanism in response to turning of said bell cranks, said assembly including a rod extending longitudinally of said comb and having ends respectively extending through said slots, said rod being guided by said slots for horizontal movement while remaining parallel to its original position, and said rod being engaged by that arm of each bell crank which is connected to a type bar, so that upon operation of a typing key lever said rod will be displaced bodily along said slots while remaining parallel to its original position, and said assem-bly further including a linkage means interconnecting both ends of said rod and said escapement mechanism, said linkage means including a transversely pivoted elongated crank proximate to said escapement mechanism and cooperating therewith, and a pair of links, each being connected, at opposite ends, to one end of said elongated crank and a corresponding end of said rod extending longitudinally of said comb.

5. A typewriter, as claimed in claim 3, in which said carriage guide comprises a bracket having a pair of upright walls at each end thereof, each wall having an outwardly directed pair of ears at its upper end formed with a slot therebetween; a crank rod extending longitudinally of said bracket and including a central crank section having a length substantially equal to the spacing between said two upright walls of said bracket, a pair of substantially rectangular U-shaped off-sets at the ends of said central crank section each having a bight parallel to said central crank section and lying in said slots be-. tween said ears to form a pivot axis for said crank, and a pair of crank ends extending coaxially with said central section and lying outside of said upright walls; and a pair of links engaged with said laterally displaceable rod and with said crank ends; said first wall of said pawl mechanism bracket having a notch in its lower edge engageable with the central section of said crank rod; said links forming part of said means interconnecting said typing key levers and said escapement mechanism.

6. A typewriter, as claimed in claim 5, in which said support base is a substantially fiat sheet metal base; the ends of said links being maintained in engagement with said crank ends by cars cut and bent upwardly from said support base and lying outside of said links to limit displacement thereof outwardly of said crank ends.

References Cited by the Examiner UNITED STATES PATENTS 767,528 8/1904 Perry 197-21 788,758 5/1905 Diss 197-88 1,059,782 4/1913 Stern 197-2] 1,147,300 7/1915 Briggs 197-88 1,167,428 1/1916 Pickles 197-22 1,185,299 5/1916 Felbel 197-97 X 1,897,699 2/ 1933 Hart 197-60 1,955,415 4/1934 Dysart 197-22 2,091,111 8/1937 Stickuey 197-22 2,238,518 4/1941 Dieck 197-159 2,294,662 9/ 1942 Helmond 197-91 2,536,619 1/1951 Yeager 197-85 2,577,467 12/1951 Kloski et a1 197-91 2,705,553 4/1955 Thomson 197-22 2,818,958 1/1958 Toeppen et al 197-85 2,859,852 11/1958 Suif 197-22 2,913,090 11/ 1959 Tholstrup 197-60 2,917,150 12/1959 Suif 197-22 2,919,784 1/1960 Morris 197-159 3,057,449 10/1962 Thomson 197-22 ROBERT E. PULFREY, Primary Examiner.

Claims

1. A TYPEWRITER COMPRISING, IN COMBINATION, A SUPPORT BASE; A KEYBOARD INCLUDING TYPING KEY LEVERS; A TYPE BAR BASKET; PIVOTALLY MOUNTED BELL CRANKS CONNECTING RESPECTIVE TYPING KEY LEVERS TO RESPECTIVE TYPE BARS OF SAID TYPE BAR BASKET; AND GUIDING AND SPACING MEANS FOR SAID TYPING KEY LEVERS AND SAID BELL CRANKS; SAID GUIDING MEANS INCLUDING A COMB EXTENDING TRANSVERSELY OF SAID BASE, REARWARDLY OF SAID KEYBOARD; SAID BASE COMPRISING A SHEET OF METAL BENT TO FORM A FORWARD WALL EXTENDING UPWARDLY OF SAID BASE, A TOP WALL EXTENDING SUBSTANTIALLY PARALLEL TO SAID BASE, AND A REAR WALL EXTENDING DOWNWARDLY FROM SAID TOP WALL TO SAID BASE; SAID FRONT AND TOP WALLS BEING FORMED WITH A PLURALITY OF SLOTS EQUAL IN NUMBER OF THE NUMBER OF TYPING KEY LEVERS AND TO THE NUMBER OF ASSOCIATED BELL CRANKS, AND SLOTS BEING CLOSED END SLOTS AND EXTENDING UPWARDLY IN SAID FRONT WAL AND REARWARDLY INTO SAID TOP WALL; THE PORTIONS OF SAID SLOTS IN SAID FRONT WALL BEING WIDER THAN THE PORTIONS THEREOF IN SAID TOP WALL; THE PORTIONS OF SAID SLOTS IN SAID FRONT WALL EACH RECEIVING A TYPING KEY LEVER AND ONE ARM OF ITS ASSOCIATED BELL CRANK, WITH CLEARANCE; THE PORTION OF EACH SLOT IN SAID TOP WALL RECEIVING, WITH CLEARANCE, THE NORMALLY UPWARDLY EXTENDING ARM OF A BELL CRANK; SAID BELL CRANKS BEING PIVOTALLY MOUNTED ON A SHAFT EXTENDING LONGITUDINALLY THROUGH SAID COMB AND MOUNTED IN WALLS EXTENDING UPWARDLY FROM THE BASE AT OPPOSITE ENDS OF SAID COMB, SAID WALLS AT OPPOSITE ENDS OF SAID COMB BEING PARALLEL TO EACH OTHER AND EACH FORMED WITH A SUBSTANTIALLY HORIZONTAL SLOT, WITH THE TWO SLOTS BEING ALIGNED; A ROD EXTENDING LONGITUDINALLY OF SAID COMB TOP WALL AND HAVING ITS ENDS ENGAGED THROUGH SAID SLOTS SAID ROD BEING ENGAGED WITH THAT ARM OF EACH BELL CRANK WHICH IS CONNECTED TO A TYPE BAR; WHEREBY, UPON OPERATION OF A TYPING KEY LEVER, SAID ROD WILL BE DISPLACED BODILY ALONG SAID SLOTS WHILE EXTENDING PARALLEL TO ITS ORIGINAL POSITION; A CARRIAGE MOVEABLY MOUNTED TRANSVERSELY OF SAID BASE; ESCAPEMENT MECHANISM CONTROLLING MOVEMENT OF SAID CARRIAGE IN ONE DIRECTION TRANSVERSELY OF SAID BASE; AND LINKAGE MEANS INTER-CONNECTING BOTH ENDS OF SAID ROD AND SAID ESCAPEMENT MECHANISM; SAID LINKAGE MEANS INCLUDING A TRANSVERSELY PIVOTED ELONGATED CRANK PROXIMATE TO SAID ESCAPEMENT MECHANISM AND COOPERATING THEREWITH, AND A PAIR OF LINKS, EACH BEING CONNECTED, AT OPPOSITE ENDS, TO ONE END OF SAID ELONGATED CRANK AND A CORRESPONDING END OF SAID ROD EXTENDING LONGITUDINALLY OF SAID COMB.