Adjustable Paper Carriage Assembly

Abstract

A paper carriage support is mounted on the supporting frame of a typewriter for angular movement about an axis parallel to the direction of movement of the carriage and to the axis of the platen. An adjusting device, including adjusting screws and stop screws, exactly determines the desired angular position of the carriage support in relation to the supporting frame, so that the impact area of the platen can be moved in the direction of the path of movement of the types of type levers whereby the rebound distance of the types is adjusted.

Description

BACKGROUND OF THE INVENTION

Rebound control arrangements are known in which the platen of a typewriter is adjusted in the direction of movement of the types. In devices according to the prior art, eccentric adjusting means are provided for displacing the carriage support with the carriage and platen which has the disadvantage that an adjustment in horizontal direction, necessarily also causes a displacement of the impact area of the platen in vertical direction. On the other hand, if the carriage position is adjusted by screws passing through slots, a precise fine adjustment cannot be obtained.

The rebound adjustment devices according to the prior art are comparatively complicated, so that a uniform adjustment of the carriage with the platen is rather difficult.

SUMMARY OF THE INVENTION

It is one object of the invention to overcome the disadvantages of the prior art, and to provide an adjustable paper carriage assembly which permits easy adjustment of the platen in the direction and toward the path of movement of the types of the type bars cooperating with the platen.

Another object of the invention is to provide a rebound distance control arrangement of extremely simple construction which can be adjusted by unskilled persons.

With these objects in view, the present invention provides a carriage support which is mounted on the supporting frame of the typewriter for movement about an axis parallel to the axis of the platen, and which can be angularly displaced about this axis and locked in the angular adjusted position.

One embodiment of the invention comprises a paper carriage including a platen having an impact area located in the path of movement of the types of a typewriter; a carriage support having guide means supporting the paper carriage for movement in the direction of the platen; means mounting the carriage support on the supporting means of the typewriter for angular movement with the paper carriage and platen about an axis parallel to the platen; and an adjusting device connected with the supporting means and with the carriage support for angularly displacing the carriage support with the paper carriage and with the platen, and for holding the same in a selected angular position. In this manner, the impact area is placed in a selected adjusted position in the path of movement of the types.

In the preferred embodiment of the invention, the carriage support is mounted by means of pivot screws on the supporting means of the typewriter. The adjusting device includes a pair of adjusting screws having threaded portions threaded into the supporting means, and head portions on which the carriage support rests. Preferably, the head portions have threaded recesses into which stop screws are threaded for holding with their heads the carriage support in a position abutting the head portions of the adjusting screws. The angular position of the carriage support with the carriage and platen is adjusted by the adjusting screws, whereupon the carriage support is locked by the stop screws in the adjusted position.

The position of the axis about which the carriage support with the carriage and platen turns, is selected so that the impact area of the platen moves along the path of the types of actuated type bars.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is partially an end view, and partially a vertical sectional view, illustrating a carriage assembly according to one embodiment of the invention; and

FIG. 2 is a plan view of the carriage assembly of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT

A paper carriage 1 supports a cylindrical platen 2 in the usual manner, and parts of the paper carriage 1 and platen 2 which are of conventional nature, are not illustrated for the sake of clarity and simplicity. Carriage 1 has a lower guide part 1a having rollers 4c, 4e guided in channels 4b, 4d of a pair of rails 4, 4a which are secured to a carriage support. Carriage support 3 is provided with a pair of arms 5, 5a formed with threaded bores 6c into which pivot screws 6, 6a are threaded so that the pivot or journal portions 6d of pivot screws 6, 6a are located in bearing bores 7g, 7h in side walls 7a, 7b of the supporting means 7 of the typewriter frame.

The carriage support 3 has two holes 8, 8a disposed at the ends of the carriage support 3 which has thinner plate portions in these regions. Each hole 8, 8a has a portion of small diameter, and a portion of larger diameter.

The lateral walls 7a, 7b of the supporting means 7 have bent plate portions 7c, 7d, each of which is provided with a threaded bore 7f into which the threaded portion 11a of an adjusting screw 11 is threaded. A counter nut 10a on the threaded portion 11a secures each adjusting screw 11 against turning movement relative to the plate portion 7c, 7d so that loosening of the adjusting screws is prevented. Each adjusting screw 11 has a hexagonal head 11c on which the bottom surface portions 3a of carriage support 3 rest. Each hexagonal head 11c is formed with a threaded recess 11d into which the threaded stem 9b of a stop screw 9 is threaded whose head 9a abuts an annular shoulder 8c of the stepped hole 8, 8a.

The axis of the angular movement of carriage support 3 is selected in relation to the position of platen 2 and impact area 2a so that platen 2 performs a limited angular movement for adjusting the rebound of the type bars 12 upon impact of the types 12a on the impact and printing area 2a of platen 2. During angular adjustment of carriage support 3 about the axis of pivot screws 6, 6a, the impact area 2a of the platen 2 moves along a circular path having its center in the axis of the pivot pins 6, 6a toward or away from types 12a approaching the impact area 2a. The lower case type face 12b is shown in the operative position opposite the impact area 2a. Type face 12b moves along a circular path about shaft 13a; the end portion of this path being transverse to the impact area 2a. The first axis defined by shaft 13a, the second axis defined by pivots 6, 6a and the impact area 2a, are substantially aligned as shown in FIG. 1.

Type bars 12 are mounted for angular movement on a shaft 13a in a segment-shaped carrier 13 and connected by wire links 14 to other parts of the type actions. Types 12a move on circular paths having end portions substantially perpendicular to impact area 2a.

In the finally adjusted position, in which the rebound is reduced to a minimum, the bottom face 3a of carriage support 3 abuts the top face of the hexagonal head portion 11c, and the annular bottom face of head 9a abuts the top face of shoulder 8c of hole 8 or 8a of carriage support 3 so that the adjusted position is exactly defined.

When the position of the platen 2, together with carriage 1 and carriage support 3 is to be adjusted for varying the rebound of the type bars 12, the stop screw 9 is first removed. By turning the hexagonal head portion 11c of adjusting screw 11, the threaded portion 11a is screwed downward or upward in the threaded hole 7f of the supporting means 7, and since the carriage support 3 rests on the top face of the hexagonal head 11c, the carriage support 3 is placed in a corresponding position. The previously loosened counter nuts 10a are then tightened so that the angular adjusted position of carriage support 3 is assured, and loosening of adjusting screw 11 is prevented.

The annular portion 3a of the bottom face of carriage support 3, which rests on the top face of head portion 11a, surrounds the threaded recess 11d in the head portion 11a, so that the stop screw 9 can be inserted into the hole 8, or 8a, and screwed into the threaded recess 11d until the annular bottom face of head 9a abuts the annular shoulder between the two stepped portions of hole 8a.

The adjusting screw 11, and the stop screw 9 at the other end of the carriage support 3 are adjusted in the same manner and to the same height so that carriage support 3 is held in the adjusted angular position in which the impact area 2a of the platen 2 is located in the proper position in relation to the path of movement of the types 12a. During adjustment, the impact area 2a moves about the axis of pivot means 6, 6a along a circular path which substantially coincides with the end portion of the path of types 12a about shaft 13a.

Since the adjustment of the rebound takes place within comparatively small tolerances, platen 2 is hardly displaced in vertical direction. Consequently, an adjustment of the height of the lines, and of the case shift, is not required.

It will be understood that each of the elements described above, or two or more together, may also arrangements a useful application in other types of rebound control arrangements differing from the types described above.

While the invention has been illustrated and described as embodied in an adjustable paper carriage assembly for adjusting the position of the impact area of the platen in the path of movement of the types, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims.

Claims

I claim:

1. In a typewriter, in combination, a rebound-reducing paper carriage assembly, comprising a paper carriage including a platen extending in one direction and having an impact area; at least one type bar having a type including at least one character type face; shaft means mounting said type bar for angular movement about a first axis radially spaced from said impact area so that said character type face moves toward said impact area along a first circular path having a path end portion transverse to said impact area; a carriage support having guide means supporting said paper carriage and platen for movement in said one direction; supporting means; means mounting said carriage support on said supporting means for angular movement with said paper carriage and said platen and impact area about a second axis substantially aligned with said first axis and said impact area, and parallel to said one direction, said second axis being radially spaced from said impact area so that said impact area is movable along a second circular path merging into said path end portion of said first circular path; and an adjusting device connected to said supporting means and to said carriage support for continuously angularly displacing said carriage support with said paper carriage, platen, and impact area about said second axis, and for holding said carriage support in a selected angular position in which the position of said impact area in said path end portion, and thereby the moment of impact of said character type face on said impact area are adjusted for reducing rebound of said type and type bar.

2. Paper carriage assembly as claimed in claim 1 wherein said carriage support has a pair of arms formed with aligned threaded bores; and wherein said mounting means includes a pair of pivot screws having threaded portions secured in said threaded bores, and pivot portions aligned along said axis and located in bearing bores formed in said supporting means for supporting said carriage support for angular movement.

3. Paper carriage assembly as claimed in claim 1 wherein said supporting means has at least one threaded bore; wherein said adjusting device includes at least one adjusting screw having a threaded portion threaded into said threaded bore of said supporting means, and a head portion having a top face on which said carriage support rests.

4. Paper carriage assembly as claimed in claim 3 wherein said head portion is a hexagonal head, and wherein said adjusting device includes a counter nut screwed onto said threaded portion and abutting said supporting means.

5. Paper carriage assembly as claimed in claim 1 wherein said adjusting device includes threaded means for adjustably supporting said carriage support on said supporting means, and locking means for said adjusting device locking said carriage support in said selected angular position.

6. In a typewriter including type bars with types movable along a path, in combination, an adjustable paper carriage assembly including a paper carriage and a platen extending in one direction and having an impact area located in the path of said types; a carriage support having guide means supporting said paper carriage for movement in said one direction, and being formed with a hole therethrough; supporting means having at least one threaded bore; means mounting said carriage support on said supporting means for angular movement with said paper carriage and said platen about an axis parallel to said one direction; and an adjusting device connected to said supporting means and to said carriage support for angularly displacing said carriage support with said paper carriage and with said platen about said axis and for holding said paper carriage with said platen in a selected angular position whereby said inpact area is placed in a selected adjusted position in said path of movement of said types, said adjusting device including at least one adjusting screw having a threaded portion threaded into said threaded bore of said supporting means, and a head portion having a top face on which said carriage support rests, said head portion being formed with a threaded recess; said adjusting screw being aligned with said hole so that an annular bottom surface portion of said carriage support surrounding said hole rests on said top face of said head portion surrounding said threaded recess; said adjusting device including a stop screw having a threaded stem passing through said hole and being threaded into said threaded recess, and having a head abutting an annular top surface portion of said carriage support so that after adjustment of said adjusting screw and tightening of said stop screw, said carriage support is locked in an adjusted position.

7. Paper carriage assembly as claimed in claim 6 wherein said head portion is a hexagonal head, and wherein said adjusting device includes a counter nut screwed onto said threaded portion and abutting said supporting means.

8. In a typewriter including type bars with types movable along a path, in combination, an adjustable paper carriage assembly, comprising a paper carriage including a platen extending in one direction and having an impact area located in said path of said types; a carriage support having guide means supporting said paper carriage for movement in said one direction; supporting means formed with two threaded bores spaced in said one direction, said carriage support being located above said supporting means and being formed with two holes passing through and being aligned, respectively with said two threaded bores; means mounting said carriage support on said supporting means for angular movement with said paper carriage and said platen about an axis parallel to said one direction; and an adjusting device connected to said supporting means and to said carriage support for angularly displacing said carriage support with said paper carriage and with said platen about said axis and for holding said paper carriage with said platen in a selected angular position whereby said impact area is placed in a selected adjusted position in said path of movement of said types, said adjusting device including two adjusting screws having head portions, and threaded portions threaded into said threaded bores, respectively, said head portions being formed with threaded recesses, respectively, said carriage support resting on the top faces of said head portion; said adjusting device further including two stop screws having threaded stems passing through said holes and being threaded into said threaded recesses in said head portions, respectively, and heads abutting top surface portions of said carriage support for pressing said carriage support into abutment with said head portions in an adjusted position of said carriage support determined by the depth which said threaded portions of said adjusting screws are threaded into said threaded bores of said supporting means.

9. Paper carriage assembly as claimed in claim 8 wherein said carriage support has a pair of arms formed with aligned threaded bores; and wherein said mounting means include a pair of pivot screws having threaded portions secured in said aligned threaded bores, and pivot portions aligned along said axis and located in bearing bores formed in said supporting means for supporting said carriage support for angular movement.

10. Paper carriage assembly as claimed in claim 8 wherein said supporting means has two plate portions in which said threaded bores are located, and wherein said adjusting device includes two counter nuts screwed onto said threaded portions of said adjusting screws and abutting said plate portions, respectively.

11. Paper carriage assembly as claimed in claim 8 wherein said carriage support has two plate portions in which said holes are located, each of said holes having a portion of small diameter through which said threaded stem passes, and a portion of larger diameter in which said head is located below the top surface of the respective plate portion of said carriage support.