US1952192A - Noiseless typewriter action - Google Patents

Description

March 27, 1934. 1,952,192

NOISELESS TYPEWRITER ACTION Filed Oct. 2, 1931 K 2 Sheets-Sheet 1 INVENTOR. RflPH/IEL Arr/ March 27, 1934. R. ATTI 1,952,192

NOISELESS TYPEWRITER ACTION Filed Oqt. 2, 1951 2 Sheets-Sheet- 2 2/ 30 35 Z5 20 /5 M 55 gi INVENTOR. RAPHAEL 1477/ By W Gu ATTORNEY Patented Mar. 27, 1934 UNITED STATES PATENT OFFICE NOISELESS TYPEWRITER ACTION tion of New York Application October 2,

, 11 Claims.

This invention relates to typewriter actions in general and more especially to noiseless typewriter actions.

Among the objects of the present invention, it is aimed to provide an improved noiseless typewriter action and an improved method of producing a noiseless typewriter impression.

In practice it has been found that ordinarily a perfectly satisfactory impression can be produced by a typewriter action if the type were merely pressed at the point of contact instead of actuated by a swinging movement into printing position with the necessary objectionable noise producing impact blow. Due to the number of characters required with a standard typewriter and to take care of like and other conditions especially when a common printing point is provided for a plurality or all of the characters, it has however been found necessary to actuate the type bar containing the character selected at a high velocity through a considerable distance before arriving at this common printing point;

To minimize, if not entirely eliminate, the noisy impact blow ordinarily resulting as aforesaid, resort has been had to many expedients. Amongst others, resort has been had to means for maintaining control of the swinging movement throughout.

In view of the foregoing, it is an object of the present invention to provide an improved noiseless typewriter action which permits actuation of the type bar selected into the common printing position at a high speed without striking the paper followed by a secondary movement emulating a pressing action.

It is still another object of the present invention to provide an improved typewriter action including a key bar, the actuation of which in the ordinary way will in turn actuate the type bar selected through an initial movement at a high speed up to the printing position without producing the impression, this being accomplished by the actuating toggle or link breaking below the center which causes the type bar to actually stop and recede thus taking from it all the momentum, and thereupon completing the printing action by a secondary movement characteristic of a pressing action.

It is still a further object of the present invention to provide an improved noiseless typewriter action embracing means for actuating the type bar selected into printing position during an initial movement at high speed, then causing the type bar to stop and recede before it touches 1931, Serial No. 566,483

the paper by reason of the actuating toggle or link breaking below the center and thereafter actuating the type bar into the impression producing position by a secondary movement characteristic of a sustained pressing action, and combining this means with a cam for controlling the final movement of the type bar through the aforesaid sustained pressing action.

These and other features, capabilities and advantages of the present invention will appear from the subjoined detail description of one specific embodiment thereof illustrated in the accompanying drawings in which Figure 1 is a side elevation of a typewriter action showing the typewriter frame and platen diagrammatically when the key bar and type bar forming part of the typewriter action are at rest;

Fig. 2 is a similar side elevation showing the key bar depressed and the type bar at the end of the initial movement and before passing to the secondary impression creating movement; and

Fig. 3 is a similar side elevation showing the key bar depressed and the type bar in the final impression creating position.

In the embodiment illustrated, the typewriter frame 1 is shown diagrammatically and having mounted thereon a single typewriter action, although it is of course obvious that any number of such actions may be used depending upon the number of characters required, whether the type bar has only a single character or a plurality of characters, and whether the platen is shifted according to the character on a type bar to be printed or the actions themselves are shifted.

On the frame 1, there is provided in the present instance a shaft 2 on which is mounted the key bar 3 typical of any number of a plurality of key bars having a key button 4 at the free end thereof in the usual way.

On the frame 1, there is also provided a shaft .5 on which is mounted the type bar 6 typical of any one of a plurality of type bars as required having in the present instance formed on its free end two type 7 and 8 illustrative of upper case type and lower case type.

Above the frame 1, there is diagrammatically shown the end of a platen 9 in position to receive an impression from a lower case type, see Fig. 2.

Each type bar 6 of an action is connected to its key bar 3 by the linkage now to be described forming one of the main features of the present invention.

The linkage consists essentially in a toggle and its operative connections. The toggle embraces the links 10 and 11 pivotally connected to one another by the pin 12 and with the left hand end "of the link 10 pivotally connected to the short extension 13 of the type bar 6 by the pin 14. The right hand end of the link 11 is slot and pin connected to the rod 15 secured to the frame 1, which end of the link 11 is enlarged and provided with the slot 16 to receive the rod 15.

For actuating the toggle aforesaid and thereby the type bar 6 into printing position, the key bar 3 is connected to the pin 12 by the links 17, 18 and 19. The links 17 and 18 are pivotally connected to one another by the pin 20. The left hand end of the link 17, see Fig. 2, is pivotally connected to the pin 12. The right hand end of the link 18 is enlarged at 21 and pivotally connected at its extreme end on the shaft 22 mounted in the frame 1. The lower end of the link 19 is pivotally connected to the key bar 3 between the shaft 2 and the key 4 preferably near the shaft 2 as indicated by the pin 23. The upper end of the link 19 is pivotally connected to the link 18 between the shaft 22 and the pin 20 preferably near the shaft 22 by the pin 24.

To guide the toggle and maintain it in operative position, that is to cause the toggle to break below the center and hold it there until it receives the last impetus for printing, the links 25 and 26 are provided which are pivotally connected to one another by thepin 27; The lower end of the link 26 is pivotally connected to the pin 12 and the upper end of the link 25 is pivotally connected to the shaft 28 mounted in the frame 1.

To form a positioning stop for the type bar 6 when at rest, there is provided the cushioning member 29 formed on the rod 30 mounted on the frame 1, which'member 29 extends across the front edge of the bar 6 preferably above the level of the shaft 5.

To urge the bar 6 into normal position of rest, there are provided the springs31, 32 and 33. The spring 31 is connected at one end to the abutment 34 formed on the key bar 3 between the pins 23 and 2 and extends up to the rod 35 mounted on the frame 1 to the rear end of the shaft 22. The spring 32 extends from the ear 36 formed on the right hand end of the link 11 to the abutment rod 37 mounted on the frame 1 preferably above the key bar 3 and its connection with the link 19. The spring 33 in the present instance extends from the abutment 38 on the link 25 back to the abutment rod 39 mounted on the frame 1.

Extending across the front edge of the link 25 to form a limiting stop for the same when the linkage is disposed in its extreme printing position, the position shown in Fig. 2, there is provided the cushioned rod 40. The location of this rod 40 is such that the position of the link 25 may be determined and permit the link 26 to swing forwardly therefrom as shown in Fig. 3 so that the'links 25 and 26 can only bend in one direction, the direction indicated in Figs. 1 and 2. From the foregoing, it will be seen that the spring 31 functions as the main return urging 15 so that the toggle 10-11, will move the type bar 6 up to the position indicated in Fig.2, where it will not engage the platen 9 nor the paper supported thereon, so long as the pin 12 is disposed above the line extending from the pin 14 to the pin 15 and that the spring 32 will on the other hand permit the link 11 to move further forward where the rear end of the slot '16 will engage the pin 15 after the pin'12 has'passed below the line extendingfrom the pin 14 to the pin 15, where due to the cooperation of the links 25 and 26, the pin 12 will be caused to move forward the required distance in'turn to actuate the link 10 and type bar 6 to cause the type 7 or 8 to engage the paper on the platen 9 as indicated in Fig. 3.

From the foregoing, it will be apparent that the initial movement transmitted to the type bar 6 by the key bar 3 will rapidly move the type bar 6 from its position of rest on the stop bar 29 to a position spaced from the paper on the platen 9 from which pointdue to the toggle breaking below the center the type bar will stop and recede and then the continued movement of the key bar 3 will result in a secondary movement being transmitted to the type bar 6 characteristic of a sustained pressing action during the movement of one-eighth of an inch more or less required to cause the printing impression.

The foregoing linkage will also cooperate to advantage with the cam 41 pivotally connected to the rod 42 mounted on the frame 1. This cam 41 functions similar to, the type bar engaging cam described at length in my co-pending patent application Serial No. 476,817 filed August 21, 1930, it having a spring 43 extending from its enlargement 44 to the abutment rod 45, mounted on the frame 1.

This cam 41 being engaged by the edge of the type bar 6' during the latter part of its movement, will positively control the velocity thereof according to the requirements during the secw ondary movement or pressing action aforesaid.

Preferably also to form a limiting stop for the link 17, there is provided the cushioned member 46, in the present instance a rubber disc mounted on the pin 15 in the path of movement of the link 17 when moving into printing position, see Fig. 3. This stop will insure maintaining the links 17 and 18 in bent position after effecting the printing impression.

It is obvious that various changes and modifications may be made to the details of the invention without departing from the general spirit of the invention as set forth in the appended claims.

I claim:

1. A typewriter action having a type bar, a toggle connected at one end to said type bar, the other end of said toggle being slot and pin connected, a spring for normally limiting the movement of said toggle and type bar to a position spaced from the platen when actuated into printing position, and means for actuating said toggle against the tensison of said spring to cause said type bar to produce a printing impression, said toggle being thus allowed to break below the center to stop the type bar and allow it to recede before being actuated into printing position.

2. The combination with a frame and a platen, of a typewriter action having a type bar pivotally connected intermediate its ends to said frame, a key bar pivotally connected at its inner end to said frame, type formed" at one end of said type bar, two pivotally connected links forming a togglepivotally connected at one end to the other endof said type bar, a stop for de termining the position of rest of said type bar, the other end of. said toggle links being slot and pin connected to said frame, a second pair of links pivotally connected to one another with one of said links connected to said toggle links and the other of said links pivotally connected to said frame, a connecting link connecting one of said second links to said key bar, a spring connecting said key bar to said frame for urging saidlinks in the period of rest to cause said typebar to rest on said stop, and a second spring cooperating with said toggle links to determine the position of said type bar at the end of an initial impression action, said key bar when actuated causing said type bar at high speed initially to approach said platen, then recede therefrom into a position spaced from said platen determined by said second spring and toggle links and then upon continued actuation causing said type bar then slowly to advance into compression creating position.

3. A printing couple comprising a platen, a type bar pivoted to swing about a single fixed center from an idle position into impression effecting relation with the platen, and actuating means positivelyconnected with said bar for swinging the same tothe platen and adapted to automatically temporarily exert a type bar movement reversing effort upon the type bar after moving the type bar through the major portion of its travel from idle position and to thereafter positively and relatively slowly force the type bar to the platen.

4. In a typewriting machine, the combination of a type bar pivoted to swing about a single center from an idle position to an impression effecting position; a normally broken toggle pivoted at one end to the type bar; means supporting the other end of the toggle; and actuatingmeans connected with the toggle to cause the same to first exert 'a thrust on the type bar to swing the type bar from idle position substantially to impression effecting position, then exert a positive pull on the swinging bar, and finally again exert a thrust on the bar, to swing the bar into impression effecting position.

5. In a typewriting machine, the combination of a type bar having a limited swinging movement about a single center from an idle position to an impression effecting position, a normally brokentoggle pivoted at one end to said type bar and having a pin and slot connection at its opposite end with a fixed support, a key, and means operable by said key andconnected with the knuckle of said toggle for breaking said toggle slightly over center and then exerting a longitudinal thrust, in a direction away from the pin and slot connected end of the toggle, on the toggle member which extends from the type bar to the toggle knuckle, when pressure is exerted on said key; said pin and slot connection being arranged to permit longitudinal movement of the toggle under said longitudinal thrust.

6. A type bar action comprising a type bar pivoted to swing about a'single center from a normal idle position to an impression effecting position, a normally folded toggle pivoted at one end to said type bar, a second normally folded toggle pivotally anchored "to the first toggle and to a fixed support, key-operated means for exerting a straightening effort on the second toggle, and means supporting the first toggle to permit the same to first fold slightly in the opposite direction and then move bodily in the direction of its pivotal connection with the typebarunder pres sure resulting from straightening-'eifort exerted on the second toggle by said keyoperated means.

7. A type bar action comprising a pivoted type bar having a heel; a depressible key; and means connected to said key and to the heel of said type bar to swing the type bar in impression effecting direction, slightly retract said type bar, and finally swing said type bar to an impression efi'ecting position beyond the position from which the bar was retracted, during a single down stroke of said depressible key.

8. In a typewriting machine, the combination of a pivoted type bar having a heel, a platen with which said bar is coactive to print and from which the bar is normally retracted, a normally broken toggle pivoted at one end to the heel of said type bar and having a pin and slot anchorage at its opposite end, two additional normally broken toggles each having a fixed pivoted anchorage at one end and pivotally anchored at its other end to the knuckle of the first toggle, key actuated means for exerting a straightening effort on one of said two additional toggles, and

.means coactive with the fixedly anchored element of the other one of said additional toggles for arresting relative straightening movement. of the elements of said toggle before the key actuated toggle is straightened and after the'firstmentioned normally broken toggle has been straightened and then slightly broken in the reverse direction.

9. In a typewriting machine, the combination of a pivoted type bar which swings rearward to print and is provided with a heel, a platen to which said type bar swings to print, a normally upwardly broken key driven toggle having a fixed pivotal anchorage at its rear end, a reversely breakable toggle normally upwardly broken and to which the forward end of the key driven toggle is pivotally anchored, said reversely breakable toggle being pivotally anchored at its forward end to the type bar heel and being pin-and-slot supported at its rear endto permit the type bar to reach the platen only when the reversely breakable toggle is moved bodily forward, and means for arresting hinge movement between the links of the reversely breakable toggle after the said toggle is slightly reversely broken and before the key driven toggle is fully extended.

10. In a typewriting machine, the combination of a pivoted type bar which swings rearward to print and is provided with a heel, a platen to which said type bar swings to print, a normally upwardly broken key driven toggle having a fixed pivotal anchorage at its rear end, a reversely breakable toggle normally upwardly broken and to which the forward end of the key driven toggle is pivotally anchored, said reverselybreakable toggle being pivotally anchored at its forward end to the type bar heel andbeing pin-and-slot supported-at its rear end to permit the type bar to reach the platen only when the reversely breakable toggle is moved bodily forward, a third normally rearwardly broken toggle having a fixed pivotal anchorage at its upper end and pivotally anchored at its lower end to the reversely breakable toggle, and a stop for limiting downward and forward swinging movement of the upper 11. A printing couple compris ng a platen, a 15 type bar pivoted to swing on a fixed center into and out of impression efiecting relation with the platen, yieldable means normally disconnected from the type bar and engageable thereby as it nears impression eflecting position to yieldingly resist completion of movement of the bar into impression eifecting position, and type bar actuating means for first rapidly swinging the bar about its pivot in impression effecting direction, then stopping the bar independently of said yieldable means, and finally swinging the bar into

Images