US3840106A

US3840106A - Automatic repeat spacing mechanism for typewriter

Info

Publication number: US3840106A
Application number: US00328494A
Authority: US
Inventors: T Ikeda; T Terashima; T Hasegawa
Original assignee: Nakajima All Co Ltd
Current assignee: NER Co Ltd A CORP OF JAPAN; Nakajima All Co Ltd
Priority date: 1972-06-10
Filing date: 1973-01-31
Publication date: 1974-10-08
Anticipated expiration: 1991-10-08
Also published as: JPS4926612U; JPS545045Y2

Abstract

A repeat escapement mechanism for automatically repetitively stepping a carriage of a typewriter while holding an actuating key in depressed position. The mechanism is operative independently of the conventional incremental stepping escapement mechanism of the typewriter and includes a pivoted member having a tooth and a camming portion biased into engagement respectively, with the star wheel and holding dog of the conventional escapement mechanism. The pivoted member normally is held in inoperative position. When the key is depressed the pivoted member is rendered operative to cam the holding dog out of engagement with the star wheel with the tooth of the pivoted member engaging the star wheel. Rotation of the star wheel by reason of the bias on the typewriter carriage effects oscillation of the pivoted member to effect repetitive stepping of the carriage.

Description

I States Patent 1191 Tkerla et a1.

[ 1 Oct. 8, 1974 AUTOMATIC REPEAT SPACING 3,312,322 4/1967 Canny 197/82 MECHANISM FOR TYPEWRITER 3,417,848 12/1968 Gallant 197/82 3,472,353 10/1969 Canny eta] 197/82 [75] Inventors: Takem1Ikeda; 0s k su 3,730,323 5/1973 Watanabe 197/82 Terashima, both of Sakaimachi; 3,735,850 5/1973 Watanabe 197/82 Tokushige Hasegawa, Tokyo, all of Japan Primary Examiner-Ernest T. Wright, Jr. Attorney, Agent, or Firm-Arnstein, Gluck, [73] Assignee. JNaakaglma All & Co. Ltd., Tokyo, weitzenfeld & Minow pan [22] Filed: Jan. 31, 1973 57 ABSTRACT [21] Appl. No; 328,494 A repeat escapement mechanism for automatically repetitively stepping a carriage of a typewriter while holding an actuating key in depressed position, The [30] Foreign Apphcatlon Pnomy Data mechanism is operative independently of the conven- June 10, 1972 Japan 47-67878 tional incremental Stepping escapemem mechanism of the typewriter and includes a pivoted member having [52] US. Cl. 197/82, 197/64 a tooth and a Camming portion biased into engage [51] 11111. Cl 34L] 19/00 ment respectively, with the star wheel and holding dog [58] held of Search 197/64, 84 84 of the conventional escapement mechanism. The piv- 197/84 871 88 oted member normally is held in inoperative position.

When the key is depressed the pivoted member is ren- [56] References C'ted dered operative to cam the holding dog out of engage- UNITED STATES PATENTS ment with the star wheel with the tooth of the pivoted 744,424 11 1903 Steiger 197 64 member gag ng the Star wheel. Rotation of the Star 937,336 10/1909 Stickney wheel by reason of the bias on the typewriter carriage 2,037,178 4/1936 Rohrer effects oscillation of the pivoted member to effect re- 7 12/1955 pp petitive stepping of the carriage. 2,896,767 7/1959 13311111611 3,028,942 4/1962 Page 197/88 6 Claims, 3 Drawmg Flgures PATENTED UBT 81374 I SHEET 101' 2 AUTOMATIC REPEAT SPACING MECHANISM FOR TYPEWRITER SUMMARY OF THE INVENTION One of the objects of this invention is the provision of an improved and simplified mechanism for repetitively incrementally stepping a typewriter carriage while merely holding an actuating key in depressed position.

A further object of this invention is the provision of a mechanism of the foregoing character which is operative independently of the conventional stepping escapement of the typewriter.

Other and further objects and advantages of this invention will become apparent from the following description when considered in connection with the accompanying drawing.

BRIEF DESCRIPTION OF THE INVENTION FIG. 1 is a perspective view showing the repeat escapement mechanism of this invention in association with the conventional escapement of a typewriter.

FIG. 2 is a fragmentary top plan view of the same.

FIG. 3 is a prespective view of an escapement member.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawing the invention is shown as applied to a well known make of commercial typewriter and only those parts of the machine which contribute directly to the essentials of the present invention have been included in the drawing.

The conventional escapement includes a star wheel 5 rotatably supported on a portion of the frame 6 and having rigidly fixed thereto a pinion 7 which meshes with the rack 8 of the carriage, not shown, normally biased by a spring motor M. An escapement member 9 is rockably supported on frame 6 and includes three generally radially directed arms a, b, and c. Arm a is connected by linkage 11 and crank 11a to the space bar 56 of the typewriter. Arm b has a terminal portion provided with a hole 50 into which is hooked one end of a tension spring 12, the other end of the spring 12 being connected to the frame 6. Arm 0 is provided at its distal end with a dog 14 and intermediately thereof with an upstanding lug 16. Superposed on the escapement member 9 and coaxially rockably supported with escapement member 9 is a pawl 17 having a holding dog 18 overlying part of the arm 0 and adapted to be engaged by lug 16. The pawl 17 has a laterally extending arm 19 having a hole 51 in its terminal portion into which is hooked one end of a tension spring 20, the other end of the spring 20 being hooked into a hole 52 in the frame 6. It will be apparent that the escapement member 9 and pawl 17 normally are biased in a counter-clockwise direction, as viewed in FIGS. 1 and 2. It will be understood that when escapement member 9 is caused to be rocked in a clockwise direction, lug 16 will engage the edge of the holding dog 18 and effect corresponding movement of the pawl 17. The star wheel 5 is held against the biasing effect of the spring motor M by the holding dog 18 which locks the star wheel 5 and pinion 7 against rotation in clockwise direction, as viewed in FIG. 2, precluding incremental stepping of the carriage.

The foregoing structure is conventional and the mechanism of our invention, hereinafter to be described, cooperates therewith to effect the intended function.

An escapement member 21 is rockably supported on a vertical pin 22 fixed in the frame 6. Said escapement member 21 includes an integral end portion 23 generally U-shaped and having a pair of parallel legs 23 connected by a cross bar 24. The escapement member 21 includes an integral camming extension 26 which is arranged to engage the holding dog 18 to effect a camming action on the dog 18, as will be hereinafter explained. The escapement member 21 includes an inte' gral triangularly shaped tooth 27 and a terminal depending lug 28 to which is connected one end of a tension spring 29, the opposite end of the spring 29 being connected to an adjustable slide member 31 secured by a screw 55 threaded in frame 6 and affording adjustment of the spring tension. Fixed to the distal end of the escapement member 21 is a flat spring 32 to the end of which is fixed a weight 33. It will be apparent that the spring 29 normally biases the escapement member 21 in a clockwise direction, as viewed in the drawing.

Rockably supported on pin 22 is an actuating member 34 which is disposed between the legs 23 of end portion 23 and which ,is connected by a link 36 to a lever 37 supported for rocking movement about the axis of pin 38. The lever 37 includes an integral reversely bent arm extension 39 which is disposed in the path of travel of the upright extension 41 of a lever 42 connected to the repeat space key 43. Lever 42 is rockable about the axis of a pin 44 which is suitably mounted on a frame portion 53 of the typewriter. A tension spring 46 is connected to lever 37 and to the frame portion 54 and normally biases lever 37 in a clockwise direction so as to maintain the actuating member 34 in engagement with the cross bar 24, as illustrated in FIG. 2. The escapement member 21 thus, is urged to rock in a counter-clockwise direction so that the tooth 27 is normally maintained out of engagement with the teeth 5a of the star wheel 5. It will be understood that the tension of the spring 46 acting on lever 37 to draw the same to the left, as viewed in FIG. 1, is greater than the tension of the spring 29 acting on the escapement member 21.

OPERATION When the conventional space bar 56 of the typewriter is depressed the escapement member 9 is caused to be rocked in a clockwise direction by linkage l1 and crank 11a 11 operatively connected to the space bar 56. Such movement causes lug 16 to engage against dog 18 and to move the same out of engagement with a tooth 5a of the star wheel 5 with which it is then engaged. The rack 8 thus, is caused to move a fraction of a step until the dog 14 engages the star wheel 5 to arrest movement of the carriage. Upon release of the space bar 56 the escapement member 9 is caused to rock in a counterclockwise direction wherein the dog 14 moves out of engagement with the teeth 50 of the star wheel 5 and the dog 18 moves into the path of travel of the teeth 5a of the star wheel to engage the next succeeding tooth 5a. In such movement the carriage and rack 8 are caused to move an additional distance to complete one step or increment of travel.

To effect automatic repeat spacing, the repeat space key 43 is depressed which rocks the extension 41 of the lever 42 towards the left, as viewed in FIG. 1, to engage against arm 39 of lever 37 thereby effecting rocking of lever 37 in a counter-clockwise direction to move the link 36 to the right, as viewed in FIG. 1. Such movement rocks the actuating member 34 clockwise out of engagement with the cross bar 24 of the escapement member 21 thereby permitting the spring 29 to draw the escapement member 21 clockwise so that tooth 27 is received in a space between two adjacent teeth 5a of the star wheel 5. Correspondingly, the extension 26 engages the holding dog 18 camming the same out of the path of travel of the teeth 5a of the star wheel 5 thereby permitting rotation of the star wheel 5. The tension exerted by the spring motor M on the carriage and rack 8 is very materially greater than that exerted by the spring 29 on the escapement member 21 to maintain the tooth 27 in a space between adjacent teeth 50 on the star wheel 5. Accordingly, so long as the repeat space key 43 is held in depressed position, the holding dog 18 is disposed out of the path of travel of the teeth 5a of the star wheel 5 and the carriage and rack 8 are permitted to move to the right, as viewed in FIG. 2, under the influence of the spring motor M. In such movement the star wheel 5 is caused to be rotated in a clockwise direction and functions in the manner of a cam acting on the tooth 27 which functions as a cam follower since the tooth 27 is biased in the direction to engage teeth 5a of the star wheel 5. The escapement member 21 thus, is caused to oscillate about its axis of rotation and in so doing causes the dog 18 to effect alternate engagement and disengagement with consecutive teeth 50 of the star wheel 5. The length of the spring 32 and the size and position of the weight 33 are adjusted longitudinally of the spring 32 at the time of assembly of the typewriter so as to achieve a predetermined frequency of oscillation thereby to control the stepping speed of the carriage and rack 8. So long as the repeat space key 43 is maintained in depressed position the above cycle is repeated and the carriage and rack 8 move automatically in incremental steps.

When the repeat space key 43 is released spring 46 draws lever 37 and link 36 to the left as viewed in FIG. 1, rocking the actuating member 34 in a counterclockwise direction into engagement with the cross bar 24 which will correspondingly rock the escapement member 21 to non-operative position to permit dog 18 to engage a tooth 5a of the star wheel 5 and arrest movement of the carriage and rack 8.

Various changes coming within the spirit of our invention may suggest themselves to those skilled in the art; hence, we do not wish to be limited to the specific embodiments shown and described or uses mentioned, but intend the same to be merely exemplary, the scope of our invention being limited only by the appended claims.

We claim:

1. In a typewriter or the like having a carriage biased by a spring motor in letter feed direction comprising a toothed star wheel operatively connected to the carriage for controlling movement of the carriage and rotatable in a predetermined direction by the biasing effect of the carriage, a first escapement mechanism operatively connected to the carriage for normally controlling the incremental stepping movements of the carriage in letter feed direction, said escapement mechanism including a holding dog normally biased by a spring into engagement with said star wheel for arresting movement of said carriage, the improvement which comprises a second escapement mechanism operative independently of said first escapement mechanism for controlling automatic repetitive incremental stepping movements of said carriage in letter feed direction, comprising a pivoted member having a tooth engageable with said star wheel and having a camming extension engageable with said holding dog and normally biased by a spring in a direction to effect such engagement whereby when said tooth is engaged with said star wheel the holding dog is displaced by said camming extension from engagement with the star wheel, an actuating member pivotally supported and normally biased by a spring into engagement with said pivoted member to maintain said pivoted member in non-operative position wherein the camming extension is disengaged from said holding dog, and an operating key connected to said actuating member to effect disengagement of said actuating member from said pivoted member and displacement of said holding dog so that the biasing effect of the carriage will effect rotation of the star wheel and oscillation of said pivotal member to effect automatic repetitive stepping movements of the carriage.

2. The invention as defined in claim 1 in which the pivoted member includes a second extension beyond the tooth and a weight attached to said second extension.

3. In a typewriter of the like having a carriage biased by a spring motor in a letter feed direction comprising a toothed star wheel operatively connected to the carriage for controlling movement of the carriage and rotatable in a predetermined direction by the biasing effect of the carriage, a first escapement mechanism 0peratively connected to the carriage for normally controlling the incremental stepping movements of the carriage in letter feed direction, said escapement mechanism including a holding dog normally biased by a spring into engagement with said star wheel for arresting movement of said carriage, the improvement which comprises a pivoted member having a tooth engageable with said star wheel and having a camming extension engageable with said holding dog and normally biased by a spring in a direction to effect such engagement whereby when said tooth is engaged with the star wheel the holding dog is displaced by said camming extension from engagement with the star wheel, and key operated means including a key biased by a spring for normally holding said pivoted member in ineffective position, said key operated means when actuated by the key rendering said pivoted member effective to oscillate upon rotation of the star wheel under the biasing effect of the carriage and thereby to effect repetitive stepping movements of the carriage.

4. The invention as defined in claim 2 in which the force exerted by the spring motor is greater than the force exerted by the spring associated with the pivoted member whereby the biasing effect of the carriage on the star wheel is greater than the biasing effect of the pivoted member on the star wheel.

5. The invention as defined in claim 3 in which the pivoted member includes a second extension beyond the tooth and a weight attached to said second extension.

6. The invention as defined in claim 5 in which the second extension comprises a flat spring.

Claims

3. In a typewriter of the like having a carriage biased by a spring motor in a letter feed direction comprising a toothed star wheel operatively connected to the carriage for controlling movement of the carriage and rotatable in a predetermined direction by the biasing effect of the carriage, a first escapement mechanism operatively connected to the carriage for normally controlling the incremental stepping movements of the carriage in letter feed direction, said escapement mechanism including a holding dog normally biased by a spring into engagement with said star wheel for arresting movement of said carriage, the improvement which comprises a pivoted member having a tooth engageable with said star wheel and having a camming extension engageable with said holding dog and normally biased by a spring in a direction to effect such engagement whereby when said tooth is engaged with the star wheel the holding dog is displaced by said camming extension from engagement with the star wheel, and key operated means including a key biased by a spring for normally holding said pivoted member in ineffective position, said key operated means when actuated by the key rendering said pivoted member effective to oscillate upon rotation of the star wheel under the biasing effect of the carriage and thereby to effect repetitive stepping movements of the carriage.