US2672227A - Typewriting machine having selective circuit closing means, including a conductive power roller - Google Patents

Description

March 16, 1954 E. J. RABENDA TYPEWRIIINC MACHINE HAVING sELECTIvE CIRCUIT CLosIN MEANS, INCLUDING A CoNDUCTIvE POWER ROLLER Filed Deo. 29, 195o Snoentor E.J.RABENDA d (Ittomeg lll Egzz. um-

Patented Mar. 16, 1954 TYPEWRITING MACHINE HAVING SELEC- TIVE CIRCUIT CLOSING MEANS, INCLUD- ING A CONDUCTIVE POWER ROLLER Edward J. Rabenda, Poughkeepsie, N. Y., assignor to International Business Machines Corporation, New York, N. Y., a corporation of New York f Application December 29, 1950, Serial No. 203,378

17 Claims. (Cl. 197-5) This invention relates to typewriting machines.

An object of the present invention is to provide an improved selective circuit closing means suitable for use in typewriting machines to enable such machines to remotely control other apparatus.

An object is to provide a circuit closing means which requires only a very small amount of additional space in the typewriting machine thereby enabling the machine to be made more compact or allowing for the installation of auxiliary mechanism or apparatus without increasing the size of the machine.

An object is to provide a selective circuit closing means which does not impose any appreciable additional loads on the mechanisms of the machine over their normal loads.

An object is to provide a circuit closing means which takes advantage of already existing parts in the machine as a means of selectively closing circuits to thereby eliminate the necessity for providing a large number of additional parts for the purpose of exercising the circuit closing function.

An object is to provide a simple and effective selective circuit closing means which is especially useful in power operated typewriters to enable, for instance, the control by such a typewriter of an auxiliary machine such as a, tape punch or card punch.

An object is to provide a selective contact I means which requires very few additional parts over the normal number of parts incidental to the type bar operating mechanism of a power operated typewriter.

An object is to provide a selective contact means in which a very highcontact pressure can be obtained without imposing any additional load on the power mechanisms of the typewriter.

Another object is to provide a selective contact means for power operated typewriters which makes use of the normal parts of the power mechanism to close the selective circuits rather than axiliary parts operated thereby so as to insure that the circuits actually will be closed when the type bars are operated and not remain dependent upon additional parts which may break, get out of timing, or not operate at all.

Other objects of the invention will be pointed out in the following description and claims and illustrated in the accompanying drawings, which disclose, by wayof example, the principle of the invention and the best mode, which has been contemplated, of applying that principle. *In the drawings:

Fig. 1 is a vertical section showing the inven tion as applied to a power operated typewriter.

Fig. 2 is a detail view in profile of one of the operating cams.

Fig. 3 is a bottom plan view of the cam shown in Fig. 2.

Fig. 4 is similar to Fig. 2 and shows a modified form of the cam which enables the contact mechanism for a single key to initiate a succession of impulses.

Fig. 5 is a diagram showing how the contact plates of the cams may be wired to control auxiliary apparatus in accordance with a conventional 2-hole combinational code.

The invention is disclosed in the drawings as applied to a well known form of electrically driven power-operated typewriting machine known commercially as the IBM Electric, the power mechanism of which is disclosed in Patent No. 2,506,444. It will be understood, however, that the invention is not limited to embodiment in a typewriter of the form illustrated but may be embodied in other typewriters by suitable modifications of the power operating devices for the type bars and other instrumentalities of the typewriting machine. Y

Since the power mechanism is now well known in the art only a very brief description thereof will be given, The type bars, illustrated by the single type bar I0 in Fig. 1, are actuated by electric motive power under control of character keys Il, which are pivoted on a cross rod l2 and restored by means of the springs i3. The power means includes, for each separate type bar lll and its character key Il, a power unit having a sublever I4 pivoted at i511 on an adjustable fulcrum member l 5 which is suitably mounted in a frame 15b. The sub-levers i4 are retained in pivotal engagement with the fulcrum members I5 by means of springs I6 which urge the sub-levers i4 in a counterclockwise direction so as to tend to restore the type bars I0. Links I1 connect sub-levers I4 to type bars l0. The latter are pivotally mounted in a well known way on a curved fulcrum wire I8 inthe usual segment.

Pivotedat Illa on the sub-levers I4 are the operating cams l 9 which, in the present caseare modiiied to enable them to function as circuit closing devices. vThe sub-levers i 4 are provided with interposers 20 which are pivotally slidably mounted at Mb on extensions Vof the sublevers I4 and are urged to the left by means of the springs 2| which are anchored to lugs formed inthe sub-levers4 1 4 and to lugs at the right-hand ends of the interposers 20. The springs 2'l hold 3 the interposers 20 in their left-hand positions with bent-over lugs 25a thereof directly under neath lugs l I a formed in the keys l i.

The cams I9 are urged in a counterclockwise direction by springs `..22 to ...engage extensions thereof `lvvith fbent-.over lugs`20b -formed *in the interposers 20.

When any key Il is depressed, the interposer 20 therefor is depressed and thereby the corresponding cam I9 is urged @clockwise .until the tread of the cam engages l'the Ipower vroller PR which rotates in the directionof the arrow 4(ig. 1). The tread is eccentric ,withfrespecttopivot Ma, consequently the rotation of the `cam will urge the pivot Ma of the :cam fto :the right .-and i rock the sub-lever in a clockwise direction to actuate the related type barto .theprinting position. Subsequently, the extension 19a of the cam will strike an adjustable finger I23 and, 4by

sliding along said finger, effect the positive disf engagement voi" r4the cam .13 ifrom :the power, roller The.. foregoing mechanism is `well ,known in the art and fully described in the above Vpatent in @greater detail.

For the purpose of effecting selective rclosure of rcircuitswhich rare representative of the-.type

`.bars .and ;oth er instrumentalities which are operated,..the power roller :PR is provided .with :a

sleeve of so-called conductive rubber instead of the `.usual frubber sleeve `and the :cams :I 9, instead -.o f,.being .molded of a `single .piece of plastic, or made cfa snglefpiece-oimetal, arearranged to provide two contact .shoes vwhich-will be-electri- ,cally connected ,by A.the @conductive rrubber sleeve `when .the camds yfeng-aged with the power-roller BR.

Theconstruction of acam 'I9 ,is shown .in Figs. :zand `3-in .which the body of the ,cam visemade of ,an .insulating material lsuch y as molded nylon, to

.the ;sides ,of Y.which are .securedin any Asuitable `.way .the .electrically conductive contact plates Mb.V These contact ,plates are insulated from -,eachiotherby the .body'of the camfand the lefthand edges thereof .are shaped .to .form with the body I9 a continuous tread surface which-is `de Signed-tto y.roll .over the .surface of lthepower roller BR. .when the-cam .is engagedtherewith, .as dey,scribed above.

When operated in this ifashion, theconductive yrubber will establish yan electrical Aconnection ,between the contact :plates [9b and Ait only -remains to provide `a means nof `connecting thel .plates ,isb to external :control circuits which Ameans lnaturally must remain effective while the ycam `|f9 .isin .motion during the .operating cycle .of the type Thismeans may lconvenienl'fly -take Vthe form `of very weak ,metallic `springs vor Lequivalent Iflexible `for .resilient electrically -con- .-duclve `.members 24 which :are hooked :intoholes Ic in the ,-plates. The .bodyfof -the cam I9 is cut Vaway `as show-n -in Fig. 3 adjacent the holes i90 may then be madeof metal. The -pair of vsprings `2A associated with -each ycam provide a `means of .conducting current `from external `circuits .to .the

plates 19h. n

In order .to .function .esa .circuit `.closing device,

it is necessary that only one plate I9b be provided for each cam I9. However, the wear on the tread surface of the cam will be more evenly distributed if the cams are provided with two plates with `the insulating material ffsandwiched JPR, thereisprovided a common brush CB (Fig.

`1) whichfmayfbear on the surface of the rubber fcronwa metalliezband associated with the power roller and electrically connected with the conductive sleeve.

vIn Fig."5, there is shown how the electric con- ;nections are made to the power roller and the conducting plates i9b to enable the typewriter to 4control .anwauxiliary machinefsuchras, :forlexample, a machineifor punching.accountingand statistical record :cards 'in vaccordance with""-the well known twelve V.position 2-hole alphabetical combinational code. ,A `machine of .this `type :is disclosed in Patent No. 1,976,618.

The alphabet in accountingandstatisticalfrecords cards is yrepresented Vby combinations fof holes inthe "0, 11, and 121indexfpoint.jpo sitions, respectively, .withtholes inthe 11 A.to .-9 index-point positions. Thus, the vletter A is represented by the combination 4of a ..12zhole and a 1 hole punched in .5a single column/.of `the card. The wires W0 to WM in.-Fig.'5 may be connected to the .twelve"punchfselecting magnets of a punch such *as disclosed inthe aboveipatent so that the common brush-CB, :powerirolier PR, and the conductive Aplates 19h function to control'the punch magnets Yin the above patent in the 4same way as the'card sensing brushes do. For example, ywhen fthe :A key of lthe ltypewriter is depressed, `'the `conductive plates '19h fortheh key will close a `circuit from the power roller PR to the wire W12 and also to the wire WI so'that current can flow `from the wire 'WI3 fthrough the .power roller PR, lthe A lconductive vplates Hb to the wires 4W12 :and Wl and thence to :the 112 punch magnet and 'the 1 fpunch'magnet which will result in punching the combination of a 12 hole and a l hole in theparticular column ofthe card which is in `register `with the punch. in the same general "fashion asa i12'brush `and a '1brush in the above .patent close circuits to :the punch magnets.

The conductive plates |911 for the'numerical keys of Athe typewriter 'close only one circuit to the corresponding wires W0 to W9. Thus, ifthe digit l is printed, the operative .conductive plate AIilb.crn'responding 4to 'the 1""ikey will 4cltise a `circuit to 'the wire Wfl and lthus .causefthe ."1" .punch magnet to operate. i,

It will be understood rthat wby 'applying solenoids to the .keys vil "of a second typewriter, fit will be possible :for the first typewriter to 'control the second typewriterlby direct circuits from the conductive plates I9b of the iirstmac'hin'e to the solenoids operating the corresponding. keys of the second typewriter. I

The foregoing are merely illustrative ways in which the machine may be usedin accordance with well-known needs. It will be understood that the cams I9 may be provided with more than two conductive plates 19h, if necessary, tb enable each cam to'close several circuits .or the cam may be made whgpy .mtal

or with a metallic insert forming the entire tread so as to close a single circuit.

The principal advantage of the foregoing sclective circuit closing means is that it requiresvery few additional parts which is a distinct advantage in a mechanism of this type because of the fact that typewriting machines are usually internally crowded with the essential parts of the typewriter mechanisms and it is seldom very convenient, when the power mechanism is designed for maximum eiciency, convenience, durability, and minimum cost, to apply auxiliary contacts without considerable additional mechanism. In the past, it has been found that the installation of this additional mechanism not only has been very inconvenient and often made it necessary to enlarge the base of the machine, but the additional mechanism has imposed an additional load on the power mechanism, thereby adversely affecting its operation.

In the present case, the springs 24 are the only additional parts which must be supplied to the type bar operating mechanisms to render the circuit closing means eifective and these springs are so arranged that they are normally initially under a relatively slight tension which is relaXed during the cycles of operation of the type bars and the retensioning of these springs when the type bars restore is very slight so as to irnpose no additional burden on the restoring springs I6 and 22 which are greatly superior in strength to the springs 24. Furthermore, the springs 2li are disposed in such a relationship to the cams I9 that the eifect thereof on the cams I9 is so trilling as to have no eiect on the force of the blow of the type bars.

An advantage of the mechanism is that good electrical contact is assured since the pressure between the conductive plates Mb and the power roller PR naturally is quite heavy in View of the fact that the power roller PR operates the power units I4 against the inertia of the parts comprising the power units and the type bars and against the tension of the springs I6 so that there should be no slippage of the treads of the cams I9 on the power roller PR.. If such a slippage does occur, it will tend toward the establishment of even better contact due to the wiping action which by itself would be a distinct advantage, if it occurred.

It will thus be seen that not only is the contact closing means very positive and reliable in its action, but the cost of installing it in the machine is negligible in comparison with other arrangements where the machine is provided with a iixed bank of contacts with specially constructed cams having extension arms, insulating pins, and the like for operating the contacts. In such structures, the contact pressure necessarily must be kept as low as possible, otherwise the type bar mechanisms are likely to be excessively loaded and a disadvantage of such mechanisrns is that it is very diilicult to adjust the spring tension of all of the contact springs so that all ofthe power units are equally loaded. In the present case, there is no such problem as there is nothing at all to adjust and the only vital reaction exerted on the power unit is the normal reaction between the power actuator and the power unit which is incidental to the operation of the type bar by power in any case.

In the drawings, the contact elements |9b are shown as being coextensive with the full length of the tread surface of the cam I9 on the assumption that it is desirable to maintain full contact throughout the entire period in which the cam I9 is in contact with the power roller PR. It is possible to obtain relative timing between the plates ISb or cause these plates to individually close more than one circuit per operation of the type bar. For example, the edges of the plates I9b along the tread could be cut away in such fashion that the actual closing of the circuit is delayed or shortened, as desired. By cutting a shallow notch in the tread portion of the plates Ib of suitable length, as in Fig. 4, each plate may be caused to emit two electrical pulses or more according to the number ,of notches lcut in the plate. Thus, the mechanism is suitable for communication' systems in which each key must control the transmission of a series of impulses rather than a single impulse. Various other modifications of the plates |91) will occur to those skilled in the art to adapt the circuit closing means to the needs of control business machines or printing telegraph receivers.

While there have been shown and described and pointed out the fundamental novel features of the invention as applied to a preferred embodiment, it will be understood that various omissions and substitutions and changes in the form and details of the device illustrated and in its operation may be made by those skilled in the art without departing from the spirit of the invention. It is the intention, therefore, to be limited only as indicated by the scope of the following claims.

What is claimed is:

l. In a power operated typewriter, character keys, type bars, a continuously movable main power actuator having an electrically conductive power driving surface and a series of power units having driven elements selectively coupled by said keys with said actuator for operating the type bars selectively, said elements having electrically conductive portions making electrical contact with said driving surface while the type bars are being operated` by said actuator.

2. A power mechanism for typewriters and like machines comprising a continuously movable main power actuator having a surface of electrically conductive material; normally inactive power units, each for operating a different instrumentality of the typewriter and including a normally disengaged driven element having an electrically conductive portion engageable with said surface so as to close a circuit when the driven element is engaged with said actuator; and means to selectively engage said elements with said actuator.

3. In a machine of the class described, a continuously movable main power actuator having an electrically conductive driving surface, a power unit having an element engageable with said surface to enable said power unit to be operated by said actuator, one of said surface and said element being insulatably mounted so as to enable a circuit to be closed by contact therebetween only when said element is engaged with said actuator, and means to elect driving engagement between said actuator and said element.

4. In a typewriting machine, a printing device, a key representative of said device, a main power roller having a driving surface of electrically conductive material, and a power unit having a mechanical connection to said printing device and including a cam element engageable by said key with said power roller to actuate said printing device and making electrical connection with said 7 surf-ece, only when the power roller is actuating said powery unit.

5. Apower mechanism for typewriting and like machines comprising a continuously movable moin power actuator having an electrically conductive surface, a power unit having a biased inoperative position in which it is free of said actuator and an operative position in which it engages with said actuator` and including an element having an electrical contact surface engaging said conductive surface when the power unit is engaged with said actuator, and means to engage said power unit with said actuator.

6. A power mechanism for typewriters and like machines comprising a continuously movable main power actuator having an electrically conductive surface, a power unit having a biased inoperative position in which it is free of said actuator and an operative position in which it engages with said actuator for operation by the latter and including an element which is normally electrically insulated from said surface but arranged to make electrical contact with said surface to close an external circuit when said power unit is engaged with said actuator, and

means to cause said power unit to engage said actuator.

7. In a machine of the class described, a power roller having an electrically conductive driving surface, a power unit comprising a sub-lever mounted for rocking movement and a cam initially rotatable on said lever to engage the cam with said surface for subsequent driving by said roller, said cam having an electrically conductive portion making `electrical contact with said surface when said cam is driven by said roller, and means to initially cause rotation of said cam.

8. In combination, a power roller having an electrically conductive surface, a normally idle power unit having a cam rotatable by said power roller and having electrical contact means making at least one electrical contact with said power roller surface when rotated by the latter, and means to move the cam into rotatable engagement with the power roller.

9,. In combination with a rotary power actuator having an electrically conductive driving surface, a power unit having an element initially movable into engagement with` said actuator for rotation thereby and including electrical contact means operative to close a plurality of separate circuits by rolling contact with said rotary actuator, and means to enga-ge said element with said actuator.

A10. In combination, a continuously movable power actuator having an electrically conductive surface, a normally idle actuated device including an element engageable with said actuator to enable the latter to actuate said device and including contact means arranged to make at least one electrical contact with said surface during the period of operation of said device by said actuator.

1l. In a power operated typewriter, character keys, type bars, a main power actuator having an electrically conductive power driving surface and a series of power units having driven elements selectively coupled by said keys with said actuator for operating the type bars selectively, said elements having electrically conductive portions making rolling electrical contact with said driving surface while the type bar-s are being op-` @rated by said. actuator.

12. In a power operated typewriter, character keys, type bars, a main power actuator having an electrically conductive power driving surface and a series of power units having driven elements selectively coupled by said keys with said actuator for operating the type bars selectively, said elements having electrically conductive portions making a plurality of successive electrical contacts with said driving surface, while the type bars are being operated by said actuator.

13. A powermechanism for typewriting and like machines comprising a main power actuator having an electrically conductive surface, a normally idle power unit engageable with said actuator and including an element having av contact element progressively engaging different successive portions of said conductive surface when the power unit is engaged with said actuator, and means to engage said power unit with said actuator.

14. A power mechanism for typewriters and like machines comprising a main power actuator having an electrically conductive surface, a normally idle power unit engageable with said actuator for operation by the latter and including an element which is normally electrically insulated from said surface but arranged to make rolling electrical contact with said surface to close an external circuit when said power unit is engaged with said actuator, and means to cause said power unit to engage said actuator.

l5. In combination. a power roller having an electrically conductive surface, a normally idle` power unit having a cam rotatable by said power roller and having electrical contact means making at least one rolling electrical contact with said power roller when rotated by the latter, and means to move the cam into rotatable engagement with the power roller.

16. In combination, a rotary actuator having an electrically conductive driving surface, a normally idle coupling element adapted for rotary driven engagement with said actuator and having a contact element electrically contacting said driving surface for rotation thereby when the first element is engaged with the actuator, and means to engage said coupling element with said actuator.

17. In a power actuated mechanism having an initiating means and a corresponding part to be actuated, a continuously movable power actuator havingt an electrically conductive driving surface, and a power unit operatively connected to move said corresponding part independently of said initiating means and having an element movable into contact with said driving surface by said initiating means to actuate said part. said element having an electrically conductive portion engageable with said surface to close a circuit when the element is engaged with said actuator.

EDWARD J. RABENDA.

References Cited in the ille of this patent UNITED STATES PATENTS

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