US3500975A - Lever-supporting assembly for typewriters and the like - Google Patents

Description

March 17, 1970 MBLAHA 3,500,975

LEVER-SUPPORTING ASSEMBLY FOR TYPEWRITERS AND THE LIKE Filed Feb. 5, 1968 2 Sheets-Sheet 1 lNVENTOR'. y Miroslav BLAHA mam his Affor'ney 7 March 17, 1970- M. BLAHA 3,500,975

LEVER-SUPPORTING ASSEMBLY FOR TYPEWRITERS AND THE LIKE Filed Feb. 5, 1968 2 Sheets-Sheet 2 INVENTORI Mwoslow BLAHA United States Patent US. Cl. 197-22 5 Claims ABSTRACT OF THE DISCLOSURE A lever-supporting assembly for typewriters and the like. The assembly includes a pair of coextensive guide plates formed with elongated registering guide openings, all of which radiate from a common center. A supporting body extends between and is fixed to the guide plates to carry the latter, and this supporting body has a plurality of ribs extending in the same general direction as the guide openings of the guide plates but spaced from each other by distances substantially greater than that between a pair of adjacent guide openings of each plate. A plurality of levers extend through the guide openings of one plate and at least partly into the guide openings of the other plate, and a common pivot shaft extends between the guide plates through all of the levers to support the latter for swinging movement. The ribs are interconnected at their outer ends by an elongated reinforcing member, and preferably they are formed with grooves, which receive the pivot shaft, one of the plates serving to retain the pivot shaft within these grooves.

BACKGROUND OF THE INVENTION The present invention relates to lever assemblies for typewriters and the like.

In particular, the invention relates to a structure for supporting and guiding the levers for swinging movement, particularly levers which form part of the mechanism of typewriters and the like to actuate the type-carrying levers in response to actuation of a typewriter key, although the system of the invention can also be used for other operating levers, such as those for bringing about shifting movements of mechanisms, as well as for operating other levers of typewriters and similar machines.

It is customary to guide levers of this general type in grooves of a suitable supporting body, which may, for example, take the form of a curved member carrying a shaft on which the levers are pivotally supported. This supporting body may take the form of a casting or a forging, and it is required that the grooves, which receive the levers, have a width on the order of 1 mm. As a result, casting of a body having such grooves can be carried out only with great difliculty, resulting in a considerable amount of bodies, which must be rejected as waste and, also, resulting in an insufficient accuracy in the bodies. Because of these latter difiiculties, it is customary to form grooves of this type by milling operations. However, since these grooves all extend along lines which radiate from a common center, it is not possible to mill them simultaneously. Such grooves must be sequentially milled so that the manufacturing costs are undersirably high. Furthermore, when it is essential, for example, to

provide a supporting body having a length of, approximately, 13 cm. with on the order of 44-46 grooves, in accordance with the particular number of typing members carried by the machine, then the entire construction is considerably weakened as a result of the presence of the large number of grooves. In the case where the grooves extend parallel to each other, it is also difiicult to carry out simultaneous milling of these grooves, particularly where some of the milling cutters are damaged. In the case where cutters become damaged, the carrier body itself becomes damaged, and an undesirable and unavoidable loss of time results from the necessity of changing damaged cutters.

SUMMARY OF THE INVENTION It is, accordingly, a primary object of the present invention to provide a structure which will avoid the above drawbacks.

In particular, it is an object of the present invention to provide a relatively simple and inexpensive structure,

which will very reliably support a system for swinging movement.

In addition, it is an object of the present invention to provide a construction of this type, which, while being simple and inexpensive, nevertheless does not sacrifice any accuracy.

In accordance with the invention, a pair of elongated guide plates are provided, these plates being parallel to each other and, respectively, formed with elongated guide openings, which radiate from a common center, with openings of one of these plates registering with the openings of the other of these plates. An elongated carrier body extends between and is fixed to the guide plates so to carry the latter, and this body is provided with elongated ribs, which extend in the general direction of the openings of the guide plates with these ribs spaced from each other by distances greater than that between a pair of adjacent guide openings of each guide plate. A plurality of levers extends through the guide openings of one of the plates and at least partly into the guide openings of the other of the plates, and a common pivot shaft extends between the guide plates and through all of the levers to support the latter for swinging movement. Preferably the ribs themselves are formed with a series of aligned grooves, in which the pivot shaft is received and one of the guide plates retains the pivot shaft within the grooves of the ribs. An elongated reinforcing member is connected with the outer ends of the ribs.

With the construction of the invention, there is the advantage of providing a device, which can be manufactured with far less labor and at far less cost than conventional constructions, while at the same time having a much higher accuracy than conventional constructions with respect to the guiding of the levers for swinging movement. Also the structure of the invention provides a reduced weight for the entire assembly and at the same time an increased strength, as compared to conventional constructions. The guide plates, for example, are made of flat sheet metal and can easily and quickly be manufactured in an inexpensive manner by common stamping operations.

BRIEF DESCRIPTION OF THE DRAWINGS The invention is illustrated, by way of example, in the accompanying drawings, which form part of this application and in which:

FIG. 1 is a fragmentary partly sectional side elevation illustrating one possible embodiment of a structure of the invention, FIG. 1 being taken along line 1-1 of FIG. 2 in the direction of the arrows;

FIG. 2 is a partial top plan view of the carrier body of the assembly of the invention;

FIG. 3 is a top plan view of one of the guide plates; and

FIG. 4 is a fragmentary sectional elevation, taken along line 4--4 of FIG. 2. in the direction of the arrows.

)ESCRIPTION OF A PREFERRED EMBODIMENT Referring now to the drawings, there is illustrated in IGS. 1, 2 and 4 a carrier body 1, which has a curved :onfiguration and which extends along the arc of a circle vhose center is not illustrated. The ends of the carrier aody 1 are respectively fixed to a pair of side plates 2 )f the frame of the machine. This carrier body 1 is proided at the region of its outer convex portion with a ilurality of radial ribs 3, which have free outer ends inter- :onnected by a reinforcing member 4, which also extends tlong an arc of a circle. The ribs 3 have upper surfaces 5, respectively formed with aligned grooves 6, which also :xtend along an arc of a circle whose center coincides with hat along which the arched or curved body 1 extends. An :longated pivot shaft 7 is received in the grooves 6 so as o be supported by the ribs 3 of the body 1.

This body 1 is formed at its upper and lower surfaces vith recesses 9 and, in addition, it is formed with a pluralty of openings 10 passing through the body 1.

A pair of elongated guide plates 12, which are stamped 'rom any suitable sheet metal, are respectively received n the recesses 9 and fixed directly to the body 1 by screws [1, which pass through. the openings 10. These elongated guide plates 12 also extend along an arc of a circle whose :enter coincides with that along which the body 1 extends. Each of the stamped guide plates 12 is formed with a )lurality of elongated rectangular guide openings 13, which 'adiate from a common center coinciding with the center )f the circle along which the plates 12 are curved, and he guide openings 13 of one plate 12 register with the guide openings 13 of the other plate 12. It will be noted )articularly from FIG. 1 that the carrier body 1 extends aetween and is fixed to the plates 12 so as to support he latter in planes which are parallel to each other.

The plurality of levers 8, respectively extend through he elongated guide openings 13 of the upper plate 12 f FIG. 1 and partly into the guide openings 13 of the ower guide plate 12, as shown in FIG. 1. Moreover, it vill be noted that the upper plate 12 serves to retain the :ommon pivot shaft 7 within the grooves 6 of the ribs 3. ['his common pivot shaft 7 extends through openings of he levers 8 so as to support the latter for swinging movenent. Thus, each pair of vertically aligned registered )penings 13 of the plates 12 serves to guide a lever 8 for movement in a vertical plane, while the common pivot .haft forms the turning axis thereof.

The levers 8 are respectively connected to draw rods l4, which are, in turn, respectively pivotally connected vith actuating keys 15, which are arranged on a common :ivot 16 carried by the machine frame structure 2. Springs [7 are suspended from a suitable support and are fixed at heir bottom ends in openings 18 of keys 15, respectively, :0 as to urge the latter, upwardly into engagement with a ixed stop member 19 extending between and carried by be members 2 of the frame structure of the machine. [he levers 8 also are connected by additional draw rods 20 to the type-carrying levers 21, which are respectively supported for swinging movement about an unillustrated pivot shaft. Thus, in response to actuation of a key 15, a lever 8 will be swung to actuate a type-carrying lever 21.

The number of ribs 3 which will be provided On the carrier body 1 will depend upon the strength of the material which is used for the body 1 and, in addition, upon the strength of the common pivot shaft 7. The distance between the ribs 3, however, is, in any event, substantially greater than the distance between any pair of adjacent guide openings 13 of each guide plate 12.

What is claimed is:

1. For use in a typewriter, a lever assembly comprising a pair of coextensive parallel guide plates, respectively formed with registering elongated guide openings, an elongated supporting body situated between and carrying said guide plates, and having a plurality of ribs extending in the general direction of said openings and spaced from each other by a distance greater than the distance between a pair of adjacent elongated openings of each of said plates, a plurality of swingable levers respectively eX- tending through the elongated openings of one of said plates and at least partly into the registering openings of the other of said plates so that said levers are guided by the registering openings of said guide plates, and an elongated shaft extending between said plates and through said levers and supported by said elongated supporting body to support the levers for swinging movement.

2. The combination of claim 1 and wherein an elongated reinforcing member is connected with outer free ends of said ribs and extends therebetween.

3. The combination of claim 1 and wherein said ribs are respectively formed with aligned grooves receiving said shaft and one of said plates retaining said shaft in said grooves.

4. The combination of claim 3 and wherein said registering openings radiate from a common center, respectively.

5. The combination of claim 4 and wherein said guide plates and body are all curved substantially along a circle whose center coincides with the center from which said plate openings radiate.

References Cited UNITED STATES PATENTS 1,181,675 5/1916 Kurowski l97-22 1,242,167 10/1917 Feiereisel l97--22 1,418,440 6/1922 Hess et al l9722 2,705,553 4/1955 Thomson l9722 3,308,915 3/1967 Rexford l9722 XR EDGAR S. BURR, Primary Examiner US. Cl. X.R. 197-17, 41

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