US2275759A - Typewriting machine - Google Patents

Description

March 10, 1942. w. F. HELMOND 2,275,759 TYPEWRITING MACHINE Filed June 22, 1959 s Sheets-Sheet 1 v L M h m INVENTOR WILL/AM E Harm/v0 AITORNEY March 10, 1942. w. F. HELMOND TYPEWRITING MACHINE Filed June 22, 1939 3 Sheets-Sheet 3 INVENTOR WILL/AM F Hana/v0 ?&

ATTORNEY Patented Mar. 10, 1942 TYPEWRITING MACHINE F William F.-Heimond, West nmroi-a, Com, as-

signor to Underwood Elliott Fisher Company, New York, N. Y., a corporation of Delaware Application June 22, 1939, Still] No. 280,544

5 Claims. (Cl. 197-74) This invention relates to typewriting I machines. and, with regard to certain more specific features thereof, to case-shifting devices particuiarly of the character in which electromagnetic or other power drive agencies are employed in the operation of shifting from one case typing position to another. 1

The invention has for one of its objects to" provide a case-shifting mechanism which shall be simple in construction, inexpensive, reliably operative, harmonic, extremely speedy in operation, and in which there shall be a marked reduction in noise.

It is another object of the invention to employ a continuously operating powerdriven shaft and to control by manipulation of a single key the coupling and uncoupling of the powerdriven shaft with the ember to be shifted, in

such manner that continued rotation of the.

power-driven shaft in one direction may be utihad for power shifting the part successively in opposite directions and so controlling the shifting movements that ,the part is brought to its opposite extremes of movement positively and quickly under definite control and without the use of any slip friction device.

'It is afurther object of the invention to drive the part to be shifted in one or both directionsin a positive manner from a power-driven toothed roller without backlash or rebound when the'ipart reaches its limit of movement.

Other objects will be in part obvious and in part pointed out particularly as the following description of a preferred embodiment of the invention proceeds.

The invention, according y. consists in the various features of construction, combination of elements. and arrangements of parts which will be exemplified by the following description and the accompanying drawings, and the scope of the application of which will be indicated in the appended claims.

In the drawings:

Fig. 1 is a view in left side elevation'of a typewriter embodying the invention. The parts are which they assume when the type-bar segment has been shifted for upper-case typingand the case-shift lock key has been depressed to lock the segment in upper-case position.

Fig. 4 is a skeletonized' perspective showing the case-shift mechanism. illustrated in Figs. 1 to 3. Y

Fig. 5 is a sub-assembly view showing the limiting stops for the case-shifting movement.

Fig. 6 is a sectional view taken substantially along the line 8-0 of Fig. 1.

Fig. 'i is a perspective view of the eccentric and ball bearing mounted strap. utilized in carrying out the invention.

Fig. 8 is a view of the parts shown in Fig. 7 taken from the reverse side of the assembly.

Referring now more in detail to'the drawings. 7

a typewriter frame is indicated generally at Ill. It has conventional side walls ll with n which is journaled a drive shaft I! in the form of a toothed or'fluted roller which is driven from any suitable source of power such as an electric motor (not shown in the drawings). Preferably, the drive shaft is continuously rotated while the typewriter is being used and the various functions of the typewriter are performed by transitory coupling of their mechanisms with the drive shaft.

In the embodiment of the invention presently described, case-shifting is efiected by movement of the type carrying segment shown in Fig. 4 at l3, but it is to be understood that the invention, in certain of its aspects, is applicable as well to typewriters in which'the platen is shifted. In the present. case the main frame of the typewriter is provided with vertical uprights one of which isshown in Fig. 4 of the drawings at ll.

Ball bearing raceways are provided in the upfrom a rock-shaft l8 pivoted in the side walls of the typewriter at i9. counterbalance springs 20 f shown in the positions which they occupy in the normal or lower-case-typing position.

Fig. 2 is a view of the case-shifting mechanism shown in Fig. 1 but with the parts in the positionswhich they occupy when the case-shift key has-been depressed to allow the power agencies to shift the type-bar segment to so-called uppercase typing position. Fig. 3 is a view of the mechanism shown in Figs. 1 and 2 but with the parts in the positions urge the segment mounting to normal or lowercase typing position. A suitable type-bar rest 2| is provided for nesting the type-bars in their rest or inoperative positions. The rest 2| is secured to the segment mounting so as to be mov- 1 able. with it in its sliding movement to different case positions.

Pivots i8 are formed by studs 22, the one at the left side of the machine being embraced by a rockable yoke 23 movable around pivot IS. The yoke has outwardly extending opposed upper and lower flanges 2i and 25 respectively through which adjustment screws 26 and 21 extend.

' These screws confine the stud 22 at the left thickness at 32 and is penetrated at its reduced portion by a reduced portion 33 at the end of the drive shaft 12. The drive shaft portion 33 is journaled in a bushing 34 secured to the inner side of the side wall; H on the typewriter frame and passes outwardly through a detent or backlash preventing member 35 pinned, brazed, or otherwise suitably secured to the eccentric 38.

Portion 33 passes further through the reduced portion 32 of the eccentric and on its end has fixed for rotation therewith a clutch wheel 36 having teeth corresponding in number dnd position to the teethon drive shaft l2. Clutch wheel 36 is thus continuously driven with the drive shaft l2 and maybe transitorily connected with the eccentric 30 by a clutch member or dog 31 pivotally mounted on the eccentric at 38 and normally urged by a spring-pressed plunger 40 in the eccentric, bearing against a tail 4| of the dog, in a direction to, engage the clutch wheel 36.

When the mechanism is in lower-case typing position, as shown in Figs. 1 and 4 of the drawings, pivoted dog 31 is held out of engagement with the clutch wheel by a lever 42, the end 43 of which has been swung into position to intercept-a tall 44 "on dog 31 and move it pivotally until its tail 4| has compressed spring 40 and abutted the bottom of a slot 45 in the eccentric 30. Lever 42 is pivoted at 46 in a plate 41 secured to the outer side of side wall II. A lever 48 is also pivoted on this plate as indicated at,

58 and corresponding ends of levers 42 and 48 are connected by a link 5| for parallel motion.

Lever 42 has an ear 52 pivoted at 53 to a link 54, the forward end of which is pivoted at 55 to an arm 56 fixed on a shaft 51. Forwardly of the typewriter frame an angle-shaped combplate 58 is secured between the side walls H.. Brackets 60 riveted to opposite ends of the angle-plate provide ears 6| which journal shaft 51, the latter being held against lateral displacement by a screw 62 at the right end of the shaft. Welded or otherwise secured to the shaft- 5'! near opposite ends are the case-shift key-levers 63 and 64 having respectively keys 65 and 66. A coil spring 61 having one end anchored to a side wall II at 68 and the other end connected to arm 56 at 16 normally holds the case-shift key-levers in their upper normal or lower-case typing positions, thus also keeping lever 52 with its end 43 engaging tail 44 of the pivoted clutch dog 31 maintaining a disengaged relation of the a clutch parts.

As either of the keys and 66 is depressed, shaft 51 will be rocked moving arm 56 and link 54 forwardly thus releasing lever 52 from the tail of the. pivoted clutch dog, whereupon springpressed plunger 40 urges the dog into engagement with one of the teeth of the continuously rotating clutch wheel 36. At the same time that lever 42 is swung on its pivot, by depression of the case-shift key, lever 48 is swung about its pivot 50 into the position shown in Fig. 3 of the where a hook 1| on the end of lever 78 drawings,

a part rotation of eccentric 30 and a lineal 'movement of strap 28 which rocks the yoke 23 and depresses the segment mounting and the entire type basket to an upper-case typing position determined by adjustable stops at opposite sides of the machine.

The position-limiting stops are shown in Fig. 5 of the drawings and comprise shackles 12- fixed against the inner surfaces of the opposite side walls ll of the frame. Each shackle confines oneend of a pack of loose metal strips 13, the opposite ends of which 'are backed up against the ends of adjustment screws 14 threaded into cars 15 projecting inwardly from the side walls of the frame. As the segment mounting is moved from one case position to another, opposite end studs 22 engage the strip packs compressing them from loose fanned condition to substantially solid packs backed up by screws 14. The eccentric and strap device provides a substantially definite control for the movement of yoke 23 and has the effect of shiftingstuds 22- quickly from one position to another and terminating with a deceleration in the rate of movement which brings the studs quickly into contact with the packs in their fanned condition and the squeezing of the laminations into tightly compressed packs backed up by the adjustment screws. This construction tends to greatly reduce the noise and shock of impact as the air between each lamination is forced out in the compressing of the pack.

As the operator releases the case-shift key, spring 61 becomes effective to move the levers 42 and 48in parallelism in the opposite direction, thus releasing hook 1| from the tail of clutch dog 31 allowing the dog to reengage the clutch wheel 36 and thus the eccentric is again moved degrees in the same direction of rotation until tail 44 of the clutch dog is intercepted by end 43 of lever 42 and the clutch engagement is again broken. In this operation the segment.

is raised to normal or lower-case typing position and spring 61 maintains the clutch disengaged until one of the case-shift lever keys is again depressed.

To insure against rebound or reverse rotation of the eccentric in the operation of the mechanism just described, a bell-crank lever 16 is pivotally mounted 'on the left side wall H of the frame at 11. A downwardly extending arm 13 of the lever is connected by a spring 60 under some tension to the side wall. A detent nose 8| of the bell-crank lever rides upon the camshaped member 35 which, as previously stated, is secured to the eccentric 30, and fits into peripheral depressions 82 and 83 as the eccentric is released after its 180 degree movementaby disengagement of the clutch.

The case-shift key-lever may be held depressed and the segment consequently maintained for repeated typing operations in its upper-case typing position by a shift-lock mechanism comprising a key-lock-lever 84. In the embodiment shown there is one of these shift lock mechanisms f r each of the key levers 63 and 64, but as they are substantially identical a description of one will latch face 99. The latch element has oppositely extending arms 9| and 92 below its pivot 86, which arms rest in an aperture 93 provided by the lever 94. An operating finger 94 on lever 89 overlies the arm 92 of the latch element and as a key 95 of lever 84 is depressed around its pivot 85 finger 94 bearing against arm 92 swings the latch element clockwise, as viewed in the drawings, against the action of return' spring 98 until latch face 99 is deposited under a lug 91 extending from the angle member 58. Release of the keys with the parts in this position allows spring 81' to exert sumcient pressure to hold the keys in their latched-down position. Thereafter depression of the case-shift key will slightly separate latch face 99 from lug 91 allowing spring 99 to restore the latch part and the lever 99 and case-shift key-lever 63 may then rise under the action of spring 81. The. latch element is also provided with an offset finger 98 which parallels and confines operating finger as between the case-shift key-lever and finger 98 in position to overlie arm 92 of the latch element.

The ball bearing between the eccentric and its strap reduces friction and also allows just sufficient looseness to nicely accommodate the device to the squeezing action hereinbefore described in respect to the laminated stops. Proper setting of the adjustment screws 19 will result in the shift being made to both case positions accurately and noiselessly. As the shift from one case position to another is in consequence of continued movement of the eccentric in the same direction, no dead center problems are involved and the movement is particularly easy. quick and positive, and especially suitable for case-shift operation in both directions under power.

The segment is, of course, carries the usual arcuate fulcrum wire I99 upon which type-bars ml are mounted to move within slots Hi2.

What is claimed is:

1. In a typewriter, a case-shift device comprising, a part to be shifted, continuously rotating means including a toothed clutch element, cam means normally quiescent and including a companion clutch element, means connecting the cam means and the part to be shifted having provision whereby rotation of said cam means causes a reciprocatory movement of the said part, and means for controlling the rotation of the cam means having provision for engaging said clutch elements, breaking the engagement upon partial rotation of the cam means, reestablishing the engagement for continued rotation of the cam means and rebreaking the engagement when full rotation has been efiected.

2. In a typewriter, a case-shift meet-,1 m comprising, a part to be shifted, a rotating-'drive-= shaft, an eccentric loose on the shaft, a clutch element fixed on the shaft, a companion clutch element on the eccentric, connections from the eccentric to the part to be shifted for transmitting motion to the partpositively in opposite directions as the eccentric moves through a complete rotation, a case-shift key, and means responsive to one movement of said key to effect engagement'of the clutch elements to rotate the eccentric a partial rotation with the drive shaft and effect disengagement of the clutchelements at the end of said partial rotation, said means being responsive to anothe'r movement of the key to effect reengagement of the clutch elements to continue the rotation of the eccentric in the same direction until it has made a completerotation and to effect disengagement of the clutch elements at the end of the complete rotation.

3. In a typewriter, a case-shift device comprising, a part to be shifted, a continuously rotating drive-shaft, an eccentric loose on said drive-shaft, a toothed clutch wheel fixed on said drive-shaft, a clutch dog pivotally mounted on said eccentric and spring-urged toward a position of engagement with the clutch wheel, a strap around said eccentric, a rocker embracing the part to be shifted and pivotally connected to the strap, a key-controlled parallel-link mechanism normally holding the clutch dog disengaged and having provision for releasingthe dog upon depression of the key and disengaging it at the end of a partial rotation of the eccentric, and having provision for again releasing the dog upon return of the key and again disengaging it upon the completion of rotation of the eccentric.

e. In a typewriter, a case-shift device comprising, a type bar segment, means mounting the segment for shifting movement, continuously rotating means, an eccentric, key-controlled clutch means for transiently coupling the eccentric to the rotating means, a strap having an anti-friction bearing around the eccentric, and a rockable member pivotally connected to the strap and embracing the mounting means for the segment.

5. In a typewriter, a case shift mechanism comprising a shaft having end bearings and arms at opposite ends, a segment-mount pivotally con-

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