US3427116A - Pen having a wear-compensating construction - Google Patents

Description

Feb. 11, 1969 H. RIEPE 3,

PEN HAVING A WEAR-COMPENSATING CONSTRUCTION Filed May 27, 1966 10 I l 5 I 6 INVENTOR.

. HELMUTH RIEPE ATTORNEY Patented Feb. 11, 1969 Claim ABSTRACT OF THE DISCLOSURE This invention is concerned essentially with a pen having a writing tip comprising a tubular fitting and a capillary wire wherein screw means are provided for adjusting the relative position of said tubular fitting and capillary wire thereby to compensate for wear of said writing tip.

The present invention relates to writing instruments.

In particular, the present invention relates to pens used, for example, in the preparation of ink drawings.

Writing instruments of the above type where the tubular fitting, whose tip directly engages the paper, is fixed to the outer tubular body of the pen nib, have considerable disadvantages not only with respect to the manufacture of the writing instrument but also with respect to its use.

Moreover, pen nibs of this type have, in general, after a certain period of use, a non-uniform wear of the tip of the instrument. This results from the fact that the tubular fitting whose tip engages the paper is made of a relatively hard metal, such as, for example, a sintered metal, while the wire which is connected to the drop-weight is made of a softer material. Such different extents of wearing between the tip of the capillary wire and the tip of the pen nib are encountered in particular in the case where the Writing instrument is used for making ink drawings on relatively new drawing sheets which contain a relatively large proportion of filler in the form of silicon dioxide.

It is a primary object of the present invention to avoid the above drawbacks.

Thus, it is an object of the present invention to provide a pen whose manufacturing costs are considerably reduced as compared to the costs required for a conventional pen.

Also, it is an object of the present invention to provide a pen which has a construction enabling the lack of uniform wear between the writing tip and the capillary wire to be compensated.

The invention is illustrated by Way of example in the accompanying drawing which forms part of the application and which illustrates one possible embodiment of a structure of the invention in a longitudinal sectional elevation.

Referring now to the drawing, the writing instrument illustrated therein includes an elongated tubular holder 2 in the form of a hollow shaft which has a hollow interior which defines the ink chamber 4. This tubular holder 2 is open at its bottom end and is threaded at its inner surface. The pen nib of the invention is threaded into the threaded wall 8 of the tubular holder 2, and this pen nib includes an outer tubular body 6 having an exterior thread which is threaded into the thread at the inner surface of the wall '8. This outer tubular body 6 of the pen nib is preferably formed at its exterior with a helical aeration canal 10 in the form of a helical groove which extends along the exterior surface of the tubular body 6 and which communicates at its top end with the interior of the tubular body 6.

The tubular body 6 is formed with a cylindrical hollow interior 12 which receives the generally cylindrical dropweight 14 which at its bottom end 24 is fixed to the top end of the capillary wire 16.

The tubular body 6 is formed at its interior with a shoulder 26 which limits the downward falling movement of the weight 14, so as to determine the bottom end position of the weight 14 and thus the bottom end position of the capillary wire 16. It will be noted that in the drawing the bottom end face 24 of the weight 14 is shown engaging the shoulder 26.

The tubular body 6 is formed at its bottom end with a bore 18 which is threaded and which receives a carrying means 20 which is of a tubular construction and which is coaxially threaded into the bore 18. The tubular fitting 22 is inserted into the tubular carrying means 20 as by having a relatively tight press fit therein, and it will be noted that all of these components are coaxially arranged with the carrying means 20 extending downwardly beyond the tubular body 6 while the fitting 22 extends downwardly beyond the carrying means 20. It is the bottom end of the fitting 22 which forms the writing tip of the instrument.

In its bottom end position, the capillary wire 16 has its bottom tip 28 projecting downwardly beyond the tip at the bottom end of the tubular fitting 22. Thus, by threading the carrying means 20 further into or further out of the tubular body 6, it is possible to adjust the extent to which the bottom end 28 of the capillary wire 16 projects beyond the bottom tip of the tubular fitting 22.

In order to be able to conveniently turn thecarrying means 20, it is provided with a structure enabling a suitable tool to be applied thereto for convenient turning thereof. In the illustrated example, the carrying means 20 is formed at its exterior with flat, key-receiving surfaces 30 which are parallel to each other and which extend parallel to the common axis of the tubular components, so that a suitable key or other wrench or suitable tool may be applied to the flats 30 for convenient turning of the carrying means 20 so as to adjust the axial position of the fitting 22 and thus adjust the extent to which the tip 28 of the capillary wire 16 projects beyond the tip of the fitting 22 The carrying means 20 can be die cast with the keyreceiving surfaces 30 formed therein, or these surfaces can be cut into the exterior of the carrying means 20 after it is manufactured.

Moreover, the carrying means 20' has a construction which enables the diameter of the fitting 22 to be identified, so that the operator will know the thickness of the line which will be provided with the writing instrument. For this purpose, the carrying means 20 may have a suitable color, or it may have a configuration which identifies the diameter of the tubular fitting 22. Also, if desired, the carrying means 20 may carry suitable iudicia, in the form of suitable marks, which identify the diameter of the fitting 22 and which are visible at the exterior of the carrying means 20.

Thus, with the structure of the invention it is extremely simple for the operator to adjust the axial position of the carrying means 20 together with a tubular fitting 22 so as to adjust the extent to which the capillary wire projects beyond the tip of the writing instrument. Moreover, the manufacturing costs are reduced because of the ease with which this adjustment can be made.

In addition, it is possible to completely remove the carrying means together with the tubular fitting and to replace it with a new carrying means and fitting, when the tip of the writing instrument is completely worn away.

What is claimed is:

1. In a pen, an elongated tubular holder having an open bottom end and defining in its interior a chamber for holding a supply of ink, and a pen nib removably carried by said holder in a position closing and projecting beyond 3 the bottom open end thereof, said nib comprising an outer elongated tubular body extending into said holder and projecting beyond the open bottom end thereof, said outer tubular body also having an open bottom and a dropweight situated in the interior of said outer tubular body for free falling movement therein to a given bottom end position, an elongated capillary wire fixed to said weight at a bottom end thereof and extending therefrom along the axis of said tubular body downwardly through said bottom open end thereof and beyond said tubular body, a tubular fitting coaxially surrounding said capillary wire with small clearance and terminating at its bottom end in a writing tip for the pen, said wire extending through and beyond said tubular fitting when said drop-weight is in its bottom end position, and adjustable tubular carrying means coaxially surrounding and fixedly carrying said tubular fitting, said tubular fitting extending downwardly beyond said carrying means and said carrying means extending into the bottom open end of said outer tubular body and having with said outer tubular body an adjustable connection providing a selective adjustment of the axial position of said carrying means and said tubular fitting therewith, with respect to said tubular body and said capillary wire when the latter is in a bottom end position determined by the bottom end position of said dropweight in said tubular body, so that by adjusting the position of said carrying means with respect to said tubular body the extent to which said capillary Wire projects beyon-d said tubular fitting in said bottom end position of said capillary wire can be adjusted, said elongated tubular holder being internally threaded, said outer elongated tubular body being exteriorly threaded for threading engagement with the said interior thread of said elongated tubular holder, said outer tubular body being formed at its exterior surface with a helical groove extending along the exterior surface of said tubular body and communicating at its top end with the interior of said outer tubular body, said outer tubular body being formed at its interior with a shoulder to limit the downward falling movement of said drop-weight, said tubular carrying means having a threaded connection with said tubular body, said carrying means having an exterior portion situated downwardly beyond said tubular body and formed with tool-receiving surfaces for receiving a tool by means of which said carrying means together with said tubular fitting can be turned for axial adjustment of said tubular fitting, and said tool-receiving surfaces being in the form of a pair of parallel exterior surface portions of said carrier means extending parallel to the axis of said tubular body and adapted to receive the mating surfaces of a tool in the form of a key by means of which said carrying means can be turned with respect to said tubular body.

References Cited UNITED STATES PATENTS 2,217,502 10/1940 Wallace 401-259 3,126,874 3/1964 Exner '401-259 X LAWRENCE CHARLES, Primary Examiner.

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