US3154184A

US3154184A - Platen adjusting means for typewriters

Info

Publication number: US3154184A
Application number: US204753A
Authority: US
Inventors: Reginald R Gallant; Wallace M Preston
Original assignee: Underwood Corp
Current assignee: Underwood Corp
Priority date: 1962-06-25
Filing date: 1962-06-25
Publication date: 1964-10-27
Anticipated expiration: 1981-10-27

Description

1964 R. R. GALLANT ETAL PLATEN ADJUSTING MEANS FOR TYPEWRITERS Filed June 25, 1962 Fri...

IN V EN TOR. Rvq/na/a fi. Ger/lam Hal/at? N. Pms fan United States Patent PLATEN ADEUSTING MEANS FER TYPEWPJEERS Reginald R. Gallant, Bristc-i, (Iona, and Wallace M.

Preston, West Springfield, Mash, assignors to Underwood Corporati-an, New York, NFL, a. corporation of Delaware Filed June 25, 1962, Ser. No. 2154,7525 Claims. (Cl. 17-149) This invention relates to typewriters and more particularly to devices therein which facilitate the adjustment of the position of the platen roll therein in respect to typing instrumentalities in order to establish suitable printing conditions for the particular work that is required to be done.

Some typewriters embody a stop ring whereagainst the type bars strike in order to control the depth of penetration of the typing blows into the paper. However, the thickness of the work sheets and the number of copies required to be typed varies greatly and for this reason the platen must be capable of adjustment in respect to the typing instrumentalities in order to establish the proper conditions of controlled typing blows.

Moreover, to facilitate best-quality typing, the machine must be constructed to enable the ready installment of platens of various hardnesses and properties suited to the particular work that is required to be done.

These features are generally known in the art but heretofore have entailed structures of complex and expensive nature, taking up an excessive amount of space and encumbering the carriage with undesirable weight.

It is an important object of the invention to provide simple, economically manufacturable and highly efficient means to facilitate the convenient adjustment of a typewriter platen with respect to the typing instrumentalities, and also in connection therewith to provide for capability of convenient substitution of platens of desired characteristics.

It is a further object of the invention to accomplish the foregoing object by mechanism which is not only simple in nature but takes up a minimum amount of space while adding very little weight to the carriage.

Other objects of the invention will become readily evident from the description which follows and in the light of the form of the invention which is illustrated in the drawings.

Now referring to the drawings, FIGURE 1 is an end elevation of a typewriter carriage looking rightwardly thereagainst but certain parts being shown sectioned,

FIGURE 2 is a front perspective illustration viewing the carriage as seen from the left, and

FIGURE 3 is an exploded-aspect perspective illustration of a platen mounting saddle element along with parts that normally are unitary therewith.

Referring now more particularly to FIGURE 2, a platen roll has oppositely reaching shafts or shaft ends indicated at 11 and 12 which carry usual platen turning knobs, one of these knobs being indicated at 11a. In a usual manner, said shafts 11 and 12 carry respectively a bushing 13 and a bushing 14, such bushings being peripherally grooved as at 15 and 16, respectively. The locations of said

bushings

13 and 14 along their respective shafts are defined in a usual manner by means not shown. The said platen roll 10 is mounted on a carriage structure which includes two

carriage ends

17 and 13, carried upright in spaced relation on a carriage rail 29. In cooperation with usual trackways, not shown, said rail 20 guides the carriage for typing and return travels.

In FIGURE 1, a type bar is indicated at 21, striking a conventional stop ring at 22, thereby to control the penetration of the type striking the work sheet on the platen.

The platen 19, by means of the peripherally grooved shaft-

bushings

13 and 14 thereon, is seated upon

saddles

25, 26 of two part-circular saddle elements 27, 28, the latter provided respectively in the

carriage ends

17 and 18. Said saddle elements 27, 28 have each a peripheral face 36 in an eccentric relationship to the centers of the

saddles

25, 26 and by such faces they are accommodated turnably in the respective carriage ends within incompiete, circular bearing faces 31, see FIGURE 1. It will be seen that said

saddles

25, 26, are radially open in an upward direction and that the carriage ends are openmouthed or radially open in the same direction generally as said saddles, thereby to allow the platen, by its

bushings

13, 14 to be placed or removed from said saddle elements.

Each of the saddle elements has integral therewith a rim 32 (FIGURE 3) flanking the outer side of the carriage end. On each saddle element, another rim is afforded by a plate 33 which is attached thereto by screws 3 Because the peripheral faces 30 or" the saddle elements 27, 28 extend around in the incomplete bearing faces 31 in excess of it is evident that the saddle elements are permanently carried in the carriage ends.

The said saddle elements are interconnected for concerted rotative adjustment in the carriage ends and to this end a shaft 35 (FIGURES l and 2) is provided on the carriage parallel to the platen roll and exterior thereof. This shaft has at each end an arm 36 integrally formed thereon and each has a pin reaching into a fork of a related plate 38. The same screws 34 which attach the plates 33 to the

saddle elements

25, 26, serve also to attach the plates 38 thereto.

The plate belonging to the saddle element 26 on the right carriage end includes forwardly of the

platen shaft bushings

13, 14 an upreaching handle 40. By movement of this handle the saddle elements are conjointly adjustable. ln FIGURE 1 the handle 49 is shown in a middle position. By moving the handle forwardly and rearwardly to the indicated other positions, the platen roll will be relocated respectively forwardly and rearwardly a small distance in substantially a horizontal plane.

Both the plates 38 are provided with several corre sponding detent notches 42 wherewith individual spring fingers 41 cooperate to retain the adjustment. A pin 39 in the right carriage end 18, in cooperation with a notch in the plate 38 thereat, establishes limits of adjustment.

The stated shaft 35 is rockably supported on the carriage frame by means comprising at each carriage end a bracket 43. The latter are each secured to the respective carriage ends 17, 18 by screws 45, in an overlying relation to forward portions of the spring fingers 41 and said brackets 43 have each a half circular ear 44 which in conjunction With the underlying spring finger 41 affords a shaft hearing.

A releasable device 47 is provided at each carriage end to hold the platen roll 16 in position upon the

saddles

25, 26. In the specific embodiment of the invention shown in the drawings, these devices comprise each a roller 48, and these rollers normally overlie the

bushings

13 and 15 in their

respective grooves

15 and 16. The said devices embody each a lever 49 to support one of the rollers and these levers have pivotal support at 56* on the opposite carriage ends. Said devices include each also a lever 51 having an operating finger piece 52 and being pivoted at 53. Bowed links 54 of resilient character connect the

levers

49 and 51 at each carriage end.

Normally, as shown, the said devices hold the platen n; roll seated in the

saddles

25, 26. However, if the finger pieces 52 are forced forwardly, their related levers 49 swing rearwardly and will place the rollers in a position indicated at 48a, FIGURE 1 This frees the platen roll Iii for upward removal. It will be seen that the pivotal joint of each bowed link 54 with the forward arm of its related lever 51 constitutes a toggle lock for the lever 49 supporting the roller. The bowed links 54- are of slightly excessive length so that they will strain as the rollers descend on the platen shaft bushings 14, 15. The pressure with which the rollers 48 bear down is sufiicient to counteract the upward pressure of the usual feed rolls, not shown, that bear upwardly against the platen roll. However, the downward pressure of the rollers 4% permit sufliciently free turning of the saddle elements 27, 28 in the carriage ends to permit their adjustment.

The novel platen adjusting structure of this invention is applicable to other typewriting machine requiring variable correlating of a platen with typing means, inclusive also machines wherein the typing means travels instead of the platen.

What we claim is:

1. In a typewriter or similar office printing machine having a platen roll formed at its ends with a pair of end shafts, a pair of frame members supporting said pair of shafts, said platen roll being removable from said frame members, and printing means movable toward said platen roll for effecting imprints, a device for adjusting the position of said platen roll with respect to said printing means according to the thickness of the work sheet and number of copies, comprising in combination:

(a) a pair of part-circular elements, each one rotatably mounted on a circular portion of a radially open slot provided on each one of said pair of frame members,

(b) a saddle provided eccentrically on each one of said elements and adapted to rotatably support the corresponding shaft of said pair, said saddles being radially open in the said frame members in the same direction as the said slots thereby to enable removal of said platen roll,

(c) the circular portions of said slots and the partcircular magnitude of said elements being in excess of 180 degrees in order to prevent removal of said elements from said frame members when said platen roll is removed from the latter,

(d) and means including manipulative means for simultaneously rotating said circular elements to adjustably displace said platen roll with respect to said printing means.

2. In a typewriting machine having a work-sheet-supporting platen with opposite shaft extensions, and having a platen-roll-supporting frame as well as printing means operable against said platen roll;

(a) means adapted in cooperation with said shaft extensions to mount said platen roll adjustably positionable into different imprint regulating positions in respect to said printing means and comprising,

(a1) two saddle elements having each an open saddle thereon to receive and locate said platen roll by its shaft extensions and thus to define the location of the platen axis, said saddle elements having circular mounting faces which surround said saddles over an angular range exceeding 180 degrees but in an eccentric relationship to the platen axis by said saddles,

(a2) said mounting means comprising further means on said frame, cooperative with said mounting faces of said saddle elements over an angular range sufficiently exceeding 180 degrees so as to mount and retain said saddle elements, adjustably turnable on said frame,

(b) said saddle elements and said frame having openings for said shaft extensions in generally corresponding directions leading from said saddles, thereby to facilitate receipt and, removal of the platen roll,

(c) and means carried on said frame and opera-tively interconnecting said saddle elements exterior of the platen roll, to facilitate concerted turning adjustments of the saddle elements on said frame and thereby to give said platen roll different imprint regulating positions.

3. in a typewriting machine having a work-sheet-supporting platen, a platen-roll-supporting frame and printing means operable against said platen roll;

(a) an eccentric mounting means for each opposite end of the platen roll, carried adjustably turnable directly on said frame to adjust the platen roll transversely of its length into different imprint regulating positions in respect to said printing means,

(b) and means to effect concerted turning adjustments of said two mounting means, comprising means supported on said frame and exterior of said platen roll to interconnect said mounting means,

(c) said platen roll having at least at one end thereof a shaft extension and the eccentric mounting means for at least such one end of the platen roll constituting a saddle element for receipt of said shaft extension,

(d) said saddle element having a circular mounting face over an angular range exceeding degrees and further having an open saddle defining the platen axis in an eccentric relationship to said circular mounting face,

(e) said frame comprising means cooperative with the mounting face of said element in an angular range exceeding 180 degrees, to mount and retain said saddle element turnably thereon,

( said saddle element and the frame thereat having openings in substantially corresponding directions away from said open saddle, thereby to facilitate receipt and removal of said shaft extension.

4. The invention set forth in claim 3, said structure further comprising,

(g) means movable to and from cooperative relation with said shaft extension of the platen roll, respec tively to confine such shaft extension turnably seated on said saddle, or to facilitate platen-roll removal,

(h) said movable means including means governed by said saddle element in accord with its varying axis defining positions of its saddle to render said shaft extension turnably seated in said saddle as well as to allow turning adjustments of said saddle element.

7 5. In a typewriting machine having a work-sheet-supporting platen roll, a platen-roll-supporting frame and printing means operable against said platen roll;

(a) an eccentric mounting means for each opposite end of the platen roll, carried adjustably turnable directly on said frame to adjust'the platen roll trans-- versely of its length into different imprint regulating positions in respect to said printing means,

(b) means to effect concerted turnin adjustments of said two mounting means, comprising means supported on said frame and exterior of said platen roll to interconnect said mounting means,

(0) said platen roll having at least at one end thereof a shaft extension and the eccentric mounting means for at least such one end of the platen roll constituting a saddle element for receipt of said shaft extension,

(d) said saddle element having a circular mounting face over an angular range exceeding 180 degrees and further having an open saddle defining the platen axis in an eccentric relationship to said circular mounting face,

(f) said saddle element and the frame thereat having openings in substantially corresponding directions away from said Open saddle, thereby to facilitate receipt and removal of said shaft extension,

(g) and means movable to and from a cooperative relation with said shaft extension, respectively to confine such shaft extension turnably seated on said saddle, or to facilitate platen-roll removal,

(h) said movable means comprising a resilient provision for pressing the roller against said shaft extension regardless of the prevailing transversely adjusted position of the platen roll, said platen being capable of rotation and the saddle element being capable of turning adjustment.

References Cited in the file of this patent UNITED STATES PATENTS McLaughlin Mar. 14, 1916 Hokanson Apr. 26, 1927 Harrold et al. June 20, 1939 Helmond Sept. 5, 1939 Ritz Sept. 4, 1951 Dooson Jan. 29, 1952 FOREIGN PATENTS Germany Apr. 3, 1922

Claims

1. IN A TYPEWRITER OR SIMILAR OFFICE PRINTING MACHINE HAVING A PLATEN ROLL FORMED AT ITS ENDS WITH A PAIR OF END SHAFTS, A PAIR OF FRAME MEMBERS SUPPORTING SAID PAIR OF SHAFTS, SAID PLATEN ROLL BEING REMOVABLE FROM SAID FRAME MEMBERS, AND PRINTING MEANS MOVABLE TOWARD SAID PLATEN ROLL FOR EFFECTING IMPRINTS, A DEVICE FOR ADJUSTING THE POSITION OF SAID PLATEN ROLL WITH RESPECT TO SAID PRINTING MEANS ACCORDING TO THE THICKNESS OF THE WORK SHEET AND NUMBER OF COPIES, COMPRISING IN COMBINATION: (A) A PAIR OF PART-CIRCULAR ELEMENTS, EACH ONE ROTATABLY MOUNTED ON A CIRCULAR PORTION OF A RADIALLY OPEN SLOT PROVIDED ON EACH ONE OF SAID PAIR OF FRAME MEMBERS, (B) A SADDLE PROVIDED ECCENTRICALLY ON EACH ONE OF SAID ELEMENTS AND ADAPTED TO ROTATABLY SUPPORT THE CORRESPONDING SHAFT OF SAID PAIR, SAID SADDLES BEING RADIALLY OPEN IN THE SAID FRAME MEMBERS IN THE SAME DIRECTION AS THE SAID SLOTS THEREBY TO ENABLE REMOVAL OF SAID PLATEN ROLL, (C) THE CIRCULAR PORTIONS OF SAID SLOTS AND THE PARTCIRCULAR MAGNITUDE OF SAID ELEMENTS BEING IN EXCESS OF 180 DEGREES IN ORDER TO PREVENT REMOVAL OF SAID ELEMENTS FROM SAID FRAME MEMBERS WHEN SAID PLATEN ROLL IS REMOVED FROM THE LATTER, (D) AND MEANS INCLUDING MANIPULATIVE MEANS FOR SIMULTANEOUSLY ROTATING SAID CIRCULAR ELEMENTS TO ADJUSTABLY DISPLACE SAID PLATEN ROLL WITH RESPECT TO SAID PRINTING MEANS.