US1795675A - Typewriting machine - Google Patents

Description

March 10, 1931.

w. P. QUENTELL 1,795,575

TYPEWRITING MACHINE Filed Jan. 4. 1929 2 Sheets-Sheet l I N V EN 0R. 4 4

mllllilllllllllllllllll March 1931- w. P. QUENTELL TYPEWRITING MACHINE 2 Sheets-Sheet 2 Filed Jan. 4. 1929 INVEN TOR.

Patented Mar. 10, 1931 UNITED STATES PATENT OFFICE WILLIAM P. QUENTELL, OF WASHINGTON, DISTRICT OF COLUMBIA TYIPEWRI'IING MACHINE Application filed January 4, 1929. Serial No. 330,232.

This invention relates to typewriting machines and, in particular, to the mechanism which efiects the bringing of the type against the platen.

An object of the invention is to reduce the sound made by the impactof the type against the paper on the platen.

Another object is to relieve the operator of furnishing all the power to efiect the print-' power mechanism.

Fig. 4 is a fragmentary view of Fig. 1 showing the position of the typebar and clutch mechanism at printing period.

' Fig. 5 is a front elevation with parts broken away and showing a transverse section of the clutch and power transmission mechanism.

Fig. 6 is an enlarged perspective detail of the typebar rocker and parts comprising it.

Fig. 7 is an enlarged plan View of part of the rocker carrying the type carrier lock ing jaws.

Fig. 8 isan enlarged detail of the clutch mechanism for connecting the rocker with the power source.

Fig. 9 is a perspective detail of a part of the rocker carrying the clutch mechanism.

Fig. 10 is an enlarged vertical sectional view of part of the clutch and power mechanism.

It is common practice in typebar writing machines to effect printing by bringing the typebar against the platen with a quick sharp motion; this is done by connecting the typebar very close to its pivot with key actuated connections, thus requiring little movement or depression of the key. The quick smack will be understood, however, that the of the type against the paper produces considerable sound and in order to reduce that sound I do not bring the typebar all the way to the platen by depression of the key and connections to the typebar near its pivot, but bring the bar only part way, to a rocker carrying a jaw or a pair of jaws which grab the typebar near the type slug and the rocker then carries, the type to the paper and presses it the required degree to print. By applying the power for printing to the type end of the typebar, instead of to the pivot end, the

type is brought against the paper in a slower motion and as the pressure exerted by the power source is through cam action, the impact of the type against the paper is gradual instead of sudden.

The foregoing and other objects of the invention, together with means whereby the same may be carried into effect, will best be understood from the following description ofcertain forms or embodiments thereof illustrated in accompanying drawings. It

articular construction described and shown has been chosen for illustrative purposes merely,

and that the invention, as defined by the claims hereunto appended, may be otherwise practised Without departing from the spirit and scope thereof.

A is the casing of a typewriting machine; B is a platen mounted in a carriage C; D is a key, Fig.2, in the center of the machine, there being the usual plurality of keys, though for clearness of illustration only one is shown here. 1 is an arcual typebar segment in which are pivotally mounted the usual number of typebars, one' of which is shown at 2. Mounted on the arc segment 1 at its center is an upright fiat post 3 provided with bent over portions or brackets 4, Fig. 2, which form supports for a rocker 5 and its axle 6. At the upper part of the rocker 5 are two bent over portions or ears 7 and 8 which serve as supports for two jaws 9 and 10, Figs. 6 and 7, pivotally mounted at 11 and 12 respectively. The

jaws are hook shaped at one end and onenart when the jaws 9 and 10 close, i. e. are moved towards one another they will overlap. A spring 13 is attached with one end to pin 15 on jaw 9 and with the other end to pin 15a on ear 7, and a spring 14 is attached with one end to pin 16 on jaw 10 and with the other end to pin 16a on ear 8, Fig. 7. These springs tensionthe jaws to close-when the rocker 5 is rocked towards the upright post 3. The jaws 9 and 10 are formed with bent down ends or tails 9a and 10a and the post 3 has arms 17 and 18 .which have bent inwardly ends 17a and 18a, Fig. 6 and the ends 17 a and 18a form hooks which overlap the tails 9a and 10a of the jaws, so that when the rocker 5 is at normal, Figs. 1 and 2, the jaws 9 and 10 will be held in open or spread apart position, Fig. 6. While I have shown two jaws, to give a more balanced appearance, it is obvious that one jaw would suffice. .The rocker 5 is formed with an extension 20 at the right side and at the extreme end of the extension, 20a, it carries a clutch escapement, that is, the parts that are part of the mechanism which connects and disconnects the rocker 5 with and from the power source. These parts I will term for convenience the clutch mechanism. It comprises a plate 21 fixed to the rocker extension 20, as at 20a. This plate 21 has a risin portion with a bent over lip 22 throug which is mounted a pin 23. The lower end of the pin 23 has attached to it a spring 24. The pin is preferably of square section and threaded so that a nut 23a in mesh with the screw thread will lower and raise the pin 23. The other end of the sprin 24 is fastened to a lever 25 at lip 26. The lever 25 is pivotally mounted on a rod 6a fixed to a bracket 26a, the rod 6a serving also as axis of the extension 20. The axis 6a and the axis 6 being in line furnish a wide bearing for the rocker 5. The lever 25 is held against a stop pin 27 on plate 21 by the spring 24. The lever 25 carries a pin or in preferred construction an antifriction roller 28 at its free end. Suflicient clearance space is left between the pin 28 and the cam groove 34 when the parts are at normal to permit of rocking of the rocker 5 when the typebar is brought into contact with the rocker. A shaft 30 to which is fixed a constantly running ratchet wheel 31 supports a loose disk 33 having a cam or in preferred construction a cam roove 34 on its side adjacent the lever 25. The roller 28 projects into the cam groove 34. The disk 33 has an extension 35 on which is pivotally mounted a pawl 36, Fig. 8. The pawl is in line with the ratchet wheel 31 and is tensioned by a spring 38 to engage the teeth 31a of the ratchet wheel, but is held out ofengagement and against a stop pin 39 as explained hereinafter.

A post 40 rises to the left of the plate 21 from the, base of the machine'and carries on 1 and impresses the type 24 against t its upper end at 41 a pivoted segment 42 held by a spring 43 against a stop pin 44 in the post 40. The segment 42 carries a pawl 45 pivoted at 46 and held against a stop pin 47 by a spring 48. The segment 42 has a portion 49 bent outward and to the plane of the ratchet wheel 31; this bent portion or finger is normally in contact with the part or finger 37 of pawl'36 and holds the'pawl 36 out of engagement with the ratchet teeth 31a. The parts are at normal in Figs. 1 and 2 and in the enlarged detail Figs. 6 and 8. The rocker 5 is forward and away from the platen B and the jaws 9 and 10 carried by the rocker are open, i. e. their hook ends are apart laterally as indicated in Fig. 6. The type carrier 2 is pivoted at 106 on the segment 1 and is controlled by its corresponding key D througli an intermediary link 102 pivoted on a. transverse rod- 104; link 102 is connected to the heel of the typecarrier 2 by link 103 and to the key lever 101 through link 100. The key lever 101 is pivoted on a transverse rod 102. A spring 105 holds the key lever and the connected-parts just described, at normal and returns those parts to normal after the key D has been depressed and released.

Operation: WVhen the key D is depressed it swings the typecarrier 2 towards the platen B, as is common in typebar machines, but before the type strikes the platen the typebar, near the type, enters between the jaws 9 and 10, striking their inner extensions 9?) and 10b, thus causing the jaws to close over the front of the typebar, and at the same time the rocker 5 with the type carrier locked to it, will be rocked towards the platen as shown in Figs. 4 and 7. When the rocker 5 rocks towards the platen, the parts at the end of extension 20 are rocked to effect connection with the power driven ratchet wheel 31, which is preferably constantly running. The plate 21 has an extension 22a at its top which engages the pawl 45 on the segment 42, thus when the rocker 5 is rocked through depression of the key D, as described, the extension 22a swings the segment 42, through its engaging pawl 45 rearwardly, thereby causing the finger 49 ofthe segment 42 to slip away from the part 37 of the pawl 36, and then the spring 38 will snap the pawl 36 into engagement of teeth 31a of the motor driven ratchet wheel 31.

The cam disk 33 is thus connected to the running ratchet Wheel 31 and rotates with it. As the roller 28 carried on lever 25 is always in engagement with the cam groove 34 and is depressed through the rotation of the cam; through such depression it rocks the rocker 5 which rocks towards the lplaten B e plated, to print. I

To prevent repeated impressions bein made, should the operator keep the key the pawl 45, and the spring 43 brings the segment 42 back to-normal while the rocker part 22a can remain in rocked position as shown in Fig. 4.

As the cam disk 33 is brought around to' its normal position in its rotation with thepower wheel 31, the arm 37 of pawl 36 will strike the finger 49 of segment 42 and lift the pawl 36 out of contact with the tooth of the ratchet wheel 31 and the disk 33 will be locked against further forward movement. When the rocker extension 22a returns to normal with the rocker 5 it will feather or lift the pawl 45 and pass under it without disturbing the segment 42.

As the rocker 5 and typebar 2 are returning to normal through motion from the power source 31, or through a spring 5e drawing the rocker 5 away from the post 3, the tails 9a and 10a of the jaws 9 and 10 are caught by the hook extensions 17a and 18a and the jaws are thereby opened or spread apart and release the typebar 2, which will return to normal position under momentum or tension of spring 105.

In order to effect a desired strength of printing impression, as well as to eliminate necessity of close adjustments in the clutch mechanism, the lever 25 which carries the roller or pin 28 and is part of the mechanism which rocks the rocker 5 after the power wheel is connected to the mechanism, is held in normal position to the plate 21 by spring 24 so that the plate 21 and lever 25 move as one, but when the type 2a is pressed against the platen before the roller 28 has been depressed to the extreme low point of the cam 34, the lever 25 will give and avoid undue strain on the parts of the mechanism. By

adjusting the tension of spring 24 through nut 23a light or heavy impression can be made in printing.

lVith this invention the operator need use only sufficient force to depress the key far enough to move the typebar part of the distance towards the printing point, namely to the rocker, when the power source will-cause the typebar to complete the printing move ment.

What I claim is v 1. In a writingma'chine, the combination of a typecarrier, a rocker for actuating said typecarrier to print, said rocker being provided with a jaw. normally out of engagement with the typecarrier but which locks the typecarrier to the rocker at a predetermined period, a power source, means for connecting said power source with said rocker to actuate the rocker to effect printing and unlock said typecarri'er from said rocker after printmg and means for causing connectlons to be effected-between said typecarrier andsaid rocker and between said rocker and said power source, said last means comprising a key with connections between said key and sald typecarrier, whereby actuation of said key brings said typecarrier into engagement with said jaw and rocks the rocker and causes actuation of the clutch mechanism to connect I said rocker with said power source.

2; In a writing machine, a typecarrier, a rocker for actuatlng said typecarrier, a support on which said rocker is pivotally mounted, a spring to hold said rocker and support apart, a jaw carried by said rocker for locking said typecarrier to said rocker, a stop on said support which engages said jaw to hold the jaw in non-locking position when the rocker is held away from the support.

3. In a writing machine, the combination of a typecarrier, a rocker for actuating said typecarrier, a pivoted locking jaw mounted on said rocker for locking the typecarrier' to. the rocker, a power source, a clutch mechanism intermediate the power source and the rocker, and a key for moving said typecarrier into engagement with said locking jaw and partially rock said rocker bringing the clutch into engagement with the power source tov further rock the rocker and complete the printing operation.

4. In a writing machine, the combination of a platen, a typecarrier, a rocker for actuating the typecarrier,'means for locking said typecarrier to said rocker at a predetermined period, a power source, a clutch for connecting said power source with said rocker to rock the rocker with the typecarrier and press the type against said platen, a yielding lever carried by said rocker, which can yield when the type is pressed against the platen before the power source has exerted its maximum force.

5-. In a writing machine, the combination of a platen, a typecarrier, a rocker for actuating the typecarrier, a power-driven ratchet wheel, a clutch intermediate said ratchet wheel and said rocker, said clutch comprising a disk normally stationary, a pawl carried by said disk for engaging said ratchet wheel, means for normally restraining said pawl from engagement with said ratchet wheel, and means for releasing said pawl from said restraining means when the rocker is rocked towards the platen to efl'ect printing.

6. In a writing machine, the combination of a typecarrier, a rocker for actuating the typecarrier, a power-driven ratchet wheel, a clutch'intermediate said'ratchet wheel and said 'rocker,'said clutch comprising a disk normally stationary, a pawl carried by said disk for engaging said ratchet'wheel, a segment engaging said pawl to normally hold the pawl out 0 wheel, said segment being pivotally mounted and held by a spring against a stop on a support for the segment, a'cam on said disk,

engagement with said ratchet a pin on said rocker, the pin being in engagement with said cam, an extension on said rocker for engaging said pivoted segment and rock it out of contact with the pawl on the disk and permit the pawl to engage the ratchet wheel and so effect motion to be transmitted from the ratchet wheel to the rocker to eifect printing.

7. In a writing machine, the combination of a typecarrier, a rocker for actuating the typecarrier, a power driven ratchet wheel a clutch intermediate said ratchet and said rocker, said clutch comprising a disk normal 1y stationary, a pawl carried by said disk for engaging said ratchet wheel, a segment pivotally mounted on a support and held by a spring against a stop to limit motion of the segment in one direction, a pawl mounted on i said segment and held by a spring against 'a stop on the segment to limit the pawls motion in one direction, said segment normally holding the pawl on the disk out of engagement with the ratchet wheel, a cam on the disk engaging a pin carried by the rocker, an extension on said rockerfor engaging the pawl carried by the segment and slip away from the segment pawl when the segment has been moved sufficiently to release the pawl on the disk and permit it to engage the ratchet wheel, to transmit motion from the ratchet wheel to the rocker to eflect printing. 8. In a typewriting machine the combination of a platen, a typecarrier, a power source,

means intermediate the typecarrier and the power source for propelling the typecarrier to the platen, said means comprising a rocker mounted independent of and normally free from the typecarrier and provided with means for locking the typecarrier to the rocker and a key with connections with the type carrier, for effecting locking the typecarrier tothe rocker and causing the power source to actuate the rocker to propel the typecarrier to the platen.

9. In a typewriting machine the combination of a platen, a typecarrier, a power source, means intermediate the typecarrier and the power source for propelling the typecarrier to the platen, said means comprising a rocker mounted independent of and normally free from the typecarrier and provided with means for locking the typecarrier to the rocker near the type end of the typecarrier and a key with connections with the typecarrier, for effecting locking the typecarrier to the rocker and causing the power source to actuate the rocker to propel the typecarrier to the platen.

In testimony whereof I aflix my signature.

WILLIAM P. QUENTELL.

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