US3643775A

US3643775A - Apparatus for power-driven typewriters and similar machines

Info

Publication number: US3643775A
Application number: US31078A
Authority: US
Inventors: Arthur Kittel; Rudi Frank; Horst Purr
Original assignee: Olympia Werke AG
Current assignee: Olympia Werke AG
Priority date: 1969-04-26
Filing date: 1970-04-23
Publication date: 1972-02-22
Anticipated expiration: 1989-02-22
Also published as: DE1921414A1; JPS4813606B1; DE1921414B2

Abstract

A mechanism for shifting lines and returning the carriage to its left-margin position in power-driven typewriters and similar machines having a drive motor, and including a manually controlled member for triggering both the line shifting and carriage return operations, two linkages resiliently connected to the member and each arranged for normally producing a respective one of the operations, and various blocking means for selectively blocking the operative connection between the member and either linkage when the operation produced by that linkage is not to occur; particularly for blocking the carriage return linkage when the carriage is already in its left-margin position. A link member resiliently connected by means of a spring to the other of the arm members of the pivotally mounted lever and operable to pivot a crank provided on the clutch to engage that clutch and return the carriage, and reciprocating elements provided to block either the connecting rod or the link when only a line shift or a carriage return, respectively, is desired.

Description

United States Patent Kittel et a1. Feb. 22, 1972 [54] APPARATUS FOR POWER-DRIVEN 778,229 12/1904 Doederlein ..l97/12O X TYPEWRITERS AND SIMILAR 2,286,318 6/1942 Sundstrand.... 197/66 MACHINES 3,200,197 8/1965 Krakusky ..l97/l20 X 2,965,211 12/1960 Toggenburger ..197/66 [72] Inventors: Arthur Kittel, Wilhelmshaven; Rudi Frank, Sande; Horst Purr, Primary Examiner-Robert E. Pulfrey helmshaven, all of Germany Assistant Examiner-R. T. Rader [73] Assignee: Olympia Werke AG, Wilhelmshaven, Ger- A'mmeySpe"cer Kaye many [57] ABSTRACT [22] Filed: Apr. 23, 1970 A mechanism for shifting lines and returning the carriage to its PP 31,078 left-margin position in power-driven typewriters and similar machines having a drive motor, and including a manually con [30] Foreign Application Priority Dam trolled member for triggering both the line shifting and carriage return operations, two linkages resiliently connected to Apr. 26, 1969 Germany UP 19 21 414.3 the member and each arranged f normally producing a respective one of the operations, and various blocking means [52] [1.5. CI ..197/66, 197/120 for Selectively blocking h operative connection between the [51] ll. Cl. ..B41 19/70 member and either linkage when the operation produced by [58] Fleld of Search ..197/65, 66, 1 15, 120 that linkage is notto occur; particularly for blocking the cap riage return linkage when the carriage is already in its left- [56] l References C'ted margin position. A link member resiliently connected by UNITED STATES PATENTS means of a spring to the other of the arm members of the pivotally mounted lever and operable to pivot a crank pro- 1 BI'PWI'I X Vided on the clutch to engage that clutch and return the car- 3,263,793 8/1966 Blngndlel J -197/120 riage, and reciprocating elements provided to block either the 2,168,448 8/1939 l 197/120 X connecting rod or the link when only a line shift or a carriage Pitman return respectively, is desired, 2,333,566 11/1943 Helmond.... .....l97/66 2,541,295 2/1951 Sagner 197/66 6 Claims, 6 Drawing Figures Lil 38 36 340 35 26 Alb T I 21 m 4 l8 4";

, 1 \f: A d V-/ 8 w r f PATENTEDFEH 22 I972 SHEET 1 UP 4 II NENTORS Arthur Kittel Rudi Frank Horst Purr BY JIM 4,

ATTOR NEYS.

PATENTEDFEB 22 I972 SHiET 2 BF 4 Arthur Kiriel Rudi Frank Horst Purr ATTORNEYS.

PAIENTEDrzazz 1912 SHEET []F 4 INVENTORS.

mmnfl K m m W i mm HUO RH ATTORNEYS.

APPARATUS FOR POWER-DRIVEN TYPEWRITERS AND SIMILAR MACHINES BACKGROUND OF THE INVENTION The present invention relates to a device for shifting lines and returning a carriage to the left-margin position in powerdriven typewriters and similar machines by means of a clutch which can be engaged by the margin set abutment of the machine to connect the power drive with a mechanism for returning the carriage.

Such devices are known per se. The return of the carriage to its left-margin position is usually accomplished after a line shift; or the line shift is accomplished without carriage return.

Most of these devices are of the type where the carriage return, together with the line shift, is effected by means of pulley cables.

A device has also become known which is provided with two independently operating gear mechanisms; one each for driving the carriage and for shifting a line.

The drive mechanism for the line shift has a single-revolution clutch with two associated curved discs. The curved disc serving for the line shift is connected with the power drive for the duration of one revolution. The curved disc provided for the movement of the carriage, however, acts through a lever arrangement on a further clutch, which connects the power drive with a mechanism for returning the carriage. The drive of the two independently operating gears is accomplished either directly or indirectly through belt drivesby the drive motor; which is simultaneously switched on when either the line shift or carriage return keys are actuated, and which is switched off after completion of the respective function.

When the carriage is returned to the left-margin position, it is moved, in the usual manner, a little past the set margin into the so-called overshoot position, and takes up its final position immediately thereafter.

During this movement, the pawls ofa detent unit used to set the margins are out-of engagement with the conventional toothed rod, and are held in the raised position until the carriage has come to rest at the set margin. Since the pawl is out of engagement with the toothed rod, a so-called margin displacement can not be avoided. This margin displacement comes about due to the fact that the pawl, which has been lifted out of the toothed rod, engages too early into a gap between the teeth and, thus, the carriage does not reach the correct margin position.

A further drawback of this prior art device is that with successive line shifting when the carriage is in the left-margin position, the carriage is moved past the margin position into the overshoot position and back again each time, which causes very annoying switching noises.

A device has become known which seeks to prevent the margin displacement by associating a longitudinally displaceable blocking latch with the gear assembly for releasing the pawl from the toothed rod. This blocking latch catches in the toothed rod shortly before the carriage has reached the margin position.

When repeated line switching in the left-margin position is performed, the pawl is lifted from the toothed rod as usual, so that the carriage with its longitudinally movable blocking latch is moved each time beyond the margin position into the overshoot position and back again.

The addition of the longitudinally displaceable blocking latch thus fixes-the left-margin position of the carriage in such a manner that it is stopped in the correct position and the pawl is able to fall into the toothed rod in this position.

The annoying switching noises repeated during the line switches are not removed by this device, however. Moreover, this arrangement is highly subject to malfunctions and, thus, not dependable.

The carriage return with the preceding line shift is accomplished in these embodiments by actuating the conventional carriage return key. A continuous line switching after completed carriage return by means of this key is not provided.

For line shifting without carriage return in the left-margin position a special line switching key disposed on the keyboard is required.

These known embodiments are relatively complicated and, thus, unnecessarily expensive, so that the total cost of the typewriter is unduly increased.

SUMMARY OF THE INVENTION It is, therefore, an object of the present invention to provide a device which eliminates the above-mentioned disadvantages and similar drawbacks, and which is particularly distinguished by its simplicity and dependability.

This is accomplished according to the present invention by providing a U-shaped bar with a pair of arms for actuating the line shift and the carriage return. This bar is pivotal about a shaft and is associated with a longitudinally movable resiliently mounted connecting rod which is joined to an inter mediate lever, and with a link which is held in operative connection with an arm of the U-shaped bar by means ofa tension spring; the link cooperating with a clutch coupling crank for connecting the carriage return mechanism with the drive mo- I01. The present invention is particularly distinguished from known devices in that the carriage return mechanism is switched off during repeated line shifts without carriage return when the carriage is in the left-margin position and, thus, in addition to the resulting reduced wear on the switching gears, the annoying and interfering switching noises are eliminated.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a front elevation view of the apparatus according to the present invention in its starting, or rest position.

FIG. 2 shows a top plan view of the apparatus of FIG. 1.

FIG. 3a shows a front elevation view of the apparatus according to the present invention in its operative position.

FIG. 3b is a front elevation view showing a detail of FIG. 311.

FIG. 4a is a front elevation view of the apparatus according to the present invention with the carriage at the left-margin and in the blocked position with the clutch disengaged.

FIG. 4b is a front elevation view similar to FIG. 3b showing a detail of FIG. 4a.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring first to FIGS. 1 and 2, element 1 is a shaft journaled in the rear wall of the housing member 2 and in a parallel intermediate wall 3 (see FIG. 2). A U-shaped lever 4 is mounted on shaft 1 so as to define a fulcrum 4'. On one end of the fulcrum 4, lever 4 is provided with an upwardly extending arm 5, while on the other end it is provided with a downwardly directed arm 6. Arm 6 is further provided with a rectangular bent portion 8 provided with a slot 7 which is open at end 7' (FIG. 2). A connecting rod 9 is associated with the upwardly extending arm 5, and is pivotally connected in a known manner with a bellcrank lever 11 which is mounted on a shaft 10 and acts on a known line shift mechanism (not shown). The connecting rod 9 is provided at its free end with a longitudinally extending, open slot 12 into which arm 5 of lever 4 engages and is held in operative connection with connecting rod 9 by a tension spring 13 fastened to connecting rod 9. In addition, the connecting rod 9 is provided with an angularly bent flap 14 which may come into operative engagement with a reciprocative blocking member 15, depending on the function to be performed. Member 15 is reciprocated by a known mechanism.

A forked link 16 engages in open slot 7 of the rectangularly bent portion 8 of arm 6, and is held there by a tension spring 17 fastened to the extension 6a of arm 6. Spring 17 is strong enough to move link 16 in unison with arm 6, if link 16 is not blocked. The other free end 16b of link 16 is provided with a longitudinally extending, open-ended slot 18 which engages a clutch crank 21. Crank 21 is pivotally mounted at 19 and is under the influence of a suitable tension spring 20. The link 16 is further provided with a protrusion which may come into operative connection with a reciprocative blocking member 22. Member 22, like member 15, is reciprocated by a known mechanism (not shown). Two cams 21a, 21b are disposed on clutch crank 21, and link 16 slides between these two cams. The clutch crank 21 is provided with a parallel extending protrusion 21c which engages in a recess portion 23b of one member 230 ofa jaw clutch 23. Clutch member 2311 is longitudinally displaceable on, and free to turn on, shaft 24 ofa suitable, known drive motor 25. The other clutch member 23' is mounted for rotation with shaft 24. A pinion 230 is provided between recess 23b and the main body of member 23a, and is permanently engaged with a freely rotatable crown wheel 27 mounted on a shaft 26 which is perpendicularly arranged with respect shaft 24. Shaft 26 is mounted in a known manner in a bearing bracket 28 mounted on the intermediate wall 3 (the mounting is not shown). The crown wheel 27 is in friction contact with a friction overload clutch 30, formed of a spring disc 29 in frictional connection with crown wheel 27. At the upper end of shaft26, there is a pinion 31 which cooperates with the rack 32 mounted on the carriage (not shown). On the socalled toothed margin set rod 33, which is part of the carriage, there is disposed the displaceable and adjustable left-margin setter 34, provided with an abutment tongue 34a. Below the toothed margin set rod 33, a shaft 35 is mounted in the frame of the machine (not shown), on which the known switching bridge 36 is mounted. Bridge 36 is held in position by a tension spring 37 and is provided with a protrusion 38 and a trip dog 39.

A switching lever 41 is mounted on a bolt 40 disposed in the rear wall 2 ofthe machine housing. This switching lever 41 is provided with an arm 41a and an upwardly directed protrusion 41b. In the rest, or starting, position the switching lever 41, together with protrusion 41b, are under the influence of a torsion spring 42 and in contact with the trip dog 39 (see FIGS. 1, 3a and 3b).

A holding rod 43 is disposed above the clutch crank 21, which rod 43 is arranged parallel to the plunger 16 and is provided with two downwardly directed

steps

43a, 43b (FIGS. 3b and 4b).

The apparatus according to the present invention operates as follows:

Depressing the carriage return key, which is known in the art and, therefore, not illustrated, causes the lever 4 to be pivoted counterclockwise by a known drive mechanism (not shown). The connecting rod 9 which is pivotally connected to lever 11, is acted on by arm and performs a pulling movement. The lever 11, which is operable to effect a line shift in a known manner, then performs a clockwise rotating movement and causes a line shift. At the same time, the plunger 16 is moved toward the right in FIG. 1 by the force ofspring 17, and causes the clutch crank 21 to perform a counterclockwise rotary movement around pivot 19. With this rotary movement, clutch member 23a, is brought into engagement with the continuously rotating member 23' of clutch 23 (FIG. 3a). Simultaneously with the displacement of plunger 16 described above, the free end of crank 21 is pulled slightly upwardly under the influence of tension spring 20, and first comes to rest in the step 43a of the holding rod 43 (FIG. 3b). The connection of the two clutch members 23 and 230 causes a rotary movement to be imparted through pinion 23c to crown wheel 27, so that the pinion 31 is disposed on shaft 26 causes the carriage to return into the left-margin position by means of rack 32.

In the starting, or rest, position, the switching bridge 36 is in contact with the protrusion 41b of switching lever 41 through its trip dog 39 (FIG. 1).

With the arrival of the abutment tongue 34a, disposed on the margin set member 34, at the protrusion 38 of switching bridge 36, during the carriage return movement to the leftmargin position, the switching lever 41 is pivoted slightly counterclockwise against the force of the torsion spring 42 the exact amount depending on the known overshoot. Arm 41a presses crank 21 out of step 43a of holding rod 43 during this pivoting movement. The crank 21 then goes to step 43b under the influence of spring 20, and clutch member 2311 is resultingly brought out of engagement with the continuously rotating clutch member 23' to interrupt the power drive.

Tension spring 36a provided in switching bridge 36 serves the purpose of marking the margin position when the carriage is manually moved to the left-margin position and, on the other hand, of absorbing the kinetic energy of the carriage in a power-driven carriage return by motor 25 after clutch 23 has been disengaged.

At the moment of release of the carriage return key, when the line shift has already been accomplished, lever 4, the link 16 and connecting rod 9 all take up their starting positions; although the carriage return itself is still going on. To protect the drive motor'25 from possible overloads, particularly when the carriage starts moving, the carriage return mechanism consisting of crown wheel 27 and pinion 31 is provided with overload clutch 29, 30, which will protect the drive motor 25 against any possibly occurring overloads.

Upon the actuation of the carriage return keyas already describedthe line shift is simultaneously actuated as well as the carriage return. Before the carriage reaches the left-margin position, however, the line shift has already been completed.

Quite often, it is necessary that one or a plurality of successive line shifts must be made after the carriage has taken up its left-margin position. This can be done with the carriage return key, as well as with the known line shift key.

For this purpose, the carriage return key can be pressed against a resistance from the normal depressed level to a further depressed level. After the carriage has completed its return into the left-margin position, the trip dog 39 of the switching bridge 36 is in contact with the protrusion 41b of the switching lever 41, such that the bent portion 41c of its arm 41a comes to lie in front of crank 21 and, blocks link 16 (FIGS. 4a,4b).

Thus, when the carriage return key is depressed further downward against a resisting element (not shown), it effects one or a plurality of successive line shifts; the carriage return being prevented by the blocking of link 16. The pivot path of arm 6 only causes a stretching of the tension spring 17 connecting link 16 and arm 60.

If a line shift is to be performed without a carriage return in any desired position of the carriage, it is done by actuating the known line shift key. With the known drive mechanism, the lever 4 is pivoted counterclockwise.

Simultaneously with the actuation of the line shift key, the blocking member 22 is moved by a known mechanism to enter the path of movement of protrusion 16c oflink 16, so that link 16 is unable to perform a longitudinal movement to the right in FIG. 4a. This has the result that again the pivoting movement of arm 6 only causes a stretching of the tension spring 17 while link 16 remains in the block starting position.

If a carriage return is to be made to the left-m argin position without a line shift, it is done by a special key (not shown), upon whose actuation the blocking member 15 is moved by a known mechanism is brought in front of flap 14 of connecting rod 9.

During the pivoting movement of arm 5, which movement is transmitted to it by the drive mechanism, the connecting rod 9 is held in its rest position by blocking member 15, while arm 5 slides in slot 12 of connecting rod 9 against the force of tension spring 13. The pivot path of arm 5 then merely stretches the spring 13.

Upon the occasion of the movement of arm 5, arm 6 positively actuates link 16 and causes the carriage to be returned, while, as intended, a line shift is omitted. With the release of the special key, the blocking member 15 again moves out of the path of movement of the flap 14 of connecting rod 9.

It will be understood that the above description of the present invention is susceptible to various modifications, changes and adaptations, and the same are intended to be comprehended within the meaning and range of equivalents of the appended claims.

We claim:

1. Apparatus for shifting lines and returning the carriage to its left-margin position in power-driven typewriters and similar machines having a drive motor, comprising, in combination:

a. a clutch having a crank and movable between a position engaged with the drive motor and a position disengaged from the drive motor;

b. a lever mounted to be pivoted and having two arm members;

c. a pivotally mounted crank member operable to cause a line shift;

d. a connecting member connected to said pivotally mounted crank member and to one of said arm members of said lever; and

e. a link member resiliently connected to the other of said arm members of said lever and operably connected to said crank of said clutch to urge said clutch into its engaged position when said lever is pivoted,

the other of said arm members having a main body and a portion at right angles to said main body, which portion has an open slot therein in which said link member is resiliently mounted, and further including a tension spring connected to said portion of said other arm member and to said link to provide the resilient connection permitting the link member to be moved longitudinally when said lever is pivoted.

2. Apparatus as defined in claim 1, wherein said connecting member defines an open slot in which said one of said arm members of said lever is mounted, and further including a tension spring connected between said connecting member and said one of said arm members to provide a resilient, operative connection between said connecting member and said one of said arm members.

3. Apparatus as defined in claim 3, further including a first blocking member which can be moved into engagement with said link member to retain said link member when only a line shift is desired, and a second blocking member movable to engage said connecting member and to retain said connecting member when only a carriage return is desired.

4. Apparatus as defined in claim 3, further including a switching lever pivotally mounted and biased by a torsion spring, and having an arm member and a protrusion, and a switching bridge arranged to engage said protrusion when the carriage is in the left-margin position and pivot said switching lever into a blocking relationship with respect to said link member.

5. Apparatus as defined in claim 4, wherein said clutch is a jaw clutch having a driving member and a driven member carrying a pinion, and further including a crown wheel in driving connection with both the carriage and said pinion.

6. Apparatus as defined in claim 5, further including a shaft on which said crown wheel is mounted to be freely rotatable, and a friction clutch in the form of a spring disc mounted on said shaft in driving engagement with said crown wheel so as to frictionally connect said crown wheel with said shaft.

Claims

1. Apparatus for shifting lines and returning the carriage to its left-margin position in power-driven typewriters and similar machines having a drive motor, comprising, in combination: a. a clutch having a crank and movable between a position engaged with the drive motor and a position disengaged from the drive motor; b. a lever mounted to be pivoted and having two arm members; c. a pivotally mounted crank member operable to cause a line shift; d. a connecting member connected to said pivotally mounted crank member and to one of said arm members of said lever; and e. a link member resiliently connected to the other of said arm members of said lever and operably connected to said crank of said clutch to urge said clutch into its engaged position when said lever is pivoted, the other of said arm members having a main body and a portion at right angles to said main body, which portion has an open slot therein in which said link member is resiliently mounted, and further including a tension spring connected to said portion of said other arm member and to said link to provide the resilient connection permitting the link member to be moved longitudinally when said lever is pivoted.