Marker tip

Abstract: A marker tip (1 or 2) for use in or forming part of a writing instrument and being of the general type formed of a fibrous and porous material. The tip (1 or 2) has a generally elongate body (3) of circular cross section and includes conically-shaped marker surfaces (5) on each of its ends. The converging end (8) of each conically-shaped marker surface (5) is positioned slightly off-centre with respect to a central axis (9) of the tip (1 or 2) such that each marker surface (5) is comprised of a variety of radial marker widths as well as a writing point (8). All such radial marker widths are inclined at equal angles with respect to the central axis (9) such that the marker tip (1 or 2), and associated writing instrument, may be held at a single angle with respect to a marking surface when drawing lines of varying widths.

Description: FIELD OF THE INVENTION The present invention relates generally to writing and marking instruments which employ the use of fibrous and porous marking tips and, more specifically, to an improved marker tip having an off-centre point which affords its user the ability to produce marking lines of infinitely variable widths without having to alter the angle at which the writing instrument is held. BACKGROUND OF THE INVENTION The use of a fibrous and porous marker tip within a writing instrument is well-known within this field of art. Generally, these tips have elongate bodies which are secured within the "ink-discharge" end of a writing instrument. A portion of each tip is typically housed within the main body of the writing instrument and connects to a reservoir area whereby it is allowed to absorb the liquid marking medium. The remaining portion of the tip extends out from the writing instrument and, as the liquid marking medium is fully absorbed by the tip, may be drawn across a marking surface to produce a line of a given width. The variety of applications to which these tips have been applied is quite great. Tips have been developed to apply permanent, water-based and even erasable types of ink. Further, tips have been manufactured having various shapes and hardnesses for use upon such marking surfaces as paper, cardboard, wallboard, wood, metal, concrete and other types of masonry surfaces. The specific designs of the various marker tips which currently exist in the prior art have been primarily dictated by a particular marking need. That is, any one particular marker tip is designed to produce effectively a limited number of line widths - typically, one or two. Any attempt to draw lines of different widths than those which a tip is specifically designed for usually requires a user to hold the writing instrument at awkward and unintended angles. Similarly, the production of thicker lines often requires that a "double line" be drawn with a narrower tip. As a result of these various marking requirements, the shapes of tips currently available include round head, bullet head, pointed, angled and multi-angled. Indeed, it would not be uncommon for one to possess a number of these markers simply to accommodate a variety of marking requirements. From the foregoing, it should be recognised that there is still a need in the marker industry for a marker tip which, when used as intended with an associated writing instrument, allows its user to create lines having a great variety of widths, can be maintained at a single angle with respect to a writing surface in producing such lines of varying widths, provides a veritable "point" for simple writing purposes and has a body which is easily adapted to the standard writing instruments which currently exist. GB-1,350,320 discloses an elongate ended writing portion which can be used to draw lines of varying width by rotating the pen, the latter being maintained at an angle of 90° to the paper on which the ink is being deposited, to effect this. According to the present invention, there is provided a marker tip for use in a writing instrument according to claim 1. Further advantageous features are set out in the sub-claims 2 to 8. Thus, the present invention provides a marker tip for use in or forming part of a writing instrument, the marker tip having an elongate body and being secured within a forward end of the writing instrument such that an outward end of the tip is provided for marking purposes and an inward end is maintained in a reservoir section of the writing instrument in absorbing relation to a liquid marking medium, characterised by a marker tip surface which, through ordinary use of the writing instrument, facilitates the production of lines of such a liquid marking medium upon a marking surface in which the lines may have a narrow width, a broad width which is considerably wider than the said narrow width, or any width which is between the said narrow width and the said broad width. Thus the present invention obviates one or more of the cumulative shortcomings associated with the variety of conventionally-shaped marker tips by providing a marker tip for example with a uniquely designed off-centre marker point. This apparatus allows lines to be drawn of an infinite number of widths between a minimum narrow width and a maximum broad width. The production of all such lines may be accomplished by holding the associated writing instrument at a single angle with respect to the marking surface Such tip also allows a relatively thin line to be drawn from its point. The marker tip may have an elongate body with a substantially circular cross section. The size of this body is such that it may be easily accommodated within the housings of conventional marking instruments. Also in this regard, the elongate body of the marker tip may include a narrow circumferential groove located at its approximate midpoint by which it may be properly secured at the end of a writing instrument. Each end of the marker tip may terminate in a point. It will be appreciated that the "cone" which is formed at each end of the marker tip has radial edges of varying widths, ranging from a minimum narrow width to a maximum broad width. Such widths, in turn, equate to the infinite number of marker surfaces which may be used to produce lines having varying widths. Since the central axis of each cone is parallel with the central axis of the tip's elongate body, the marker tip may be maintained at the same exact writing angle no matter which line width is being produced. Indeed, the marker tip need only be rotated about its central axis until the desired marker surface width is adjacent to the intended marking surface. Should it then be desired to use the point of the marker tip for true writing purposes, the instrument may be held at a slightly greater angle with respect to the writing surface (much as a pen or pencil is typically held) and used accordingly. It is therefore a general aim of the present invention to provide a marker tip for use with or as part of conventional marking instruments which allows an infinite number of line widths to be drawn between a minimum and maximum line width. It is possible to allow the user of such a marking instrument to maintain the marker tip at a single angle with respect to the marking surface regardless of the line width being drawn. In addition, the marker tip may include a point by which the tip may be employed as a true writing instrument. Further aims and advantages of embodiments of the invention will become apparent to those of ordinary skill in the pertinent art upon review of the following detailed description, accompanying drawing and appended claims. BRIEF DESCRIPTION OF THE DRAWING Examples of a marker tip embodying the present invention are illustrated more or less diagrammatically in the accompanying drawing, in which: Figure 1 is a side view of a preferred embodiment of a marker tip in accordance with the present invention having a substantially flat writing surface; Figure 2 is a top view of the marker tip shown in Figure 1; Figure 3 is an end view of the marker tip shown in Figure 1; Figure 4 is a side view of an alternative embodiment of a marker tip in accordance with the present invention, having a slightly convex writing surface; Figure 5 is a top view of the marker tip shown in Figure 4; and Figure 6 is an end view of the marker tip shown in Figure 4. Notice must be taken that the figures are not necessarily to scale and that the embodiments are sometimes illustrated by graphic symbols, phantom lines, and diagrammatic representations. In certain instances, details which are not necessary for an understanding of the present invention or which render other details difficult to perceive may have been omitted. It should be understood, of course, that the invention is not necessarily limited to the particular embodiments illustrated herein. DETAILED DESCRIPTION OF THE DRAWING Like reference numerals will be used to refer to like or similar parts from Figure to Figure in the following description of the drawing. An off-centre point marker tip 1 is primarily defined by its longitudinal exterior surface 3, mounting groove 4 and conical marker ends 5. This particular embodiment shoes two conical marker ends 5 which are identical, but simply rotated 180° with respect to each other along the tip's central longitudinal axis 9. It must be noted, however, that the angular orientation of each marker end 5 with respect to the other is purely random. The marker tip 1 is formed of a fibrous and porous material which allows for the absorption of a liquid marking medium (typically, some form of ink). The present invention also contemplates, however, the formation of a marker tip of other types of materials such as plastics and metal. Each conical marker end 5 includes both a maximum end width 6 and minimum end width 7. Such design is accomplished by positioning the point 8 of the conical marker end 5 closer to one edge of the longitudinal exterior surface 3, rather than directly upon the tip's central longitudinal axis 9. Indeed, the present invention contemplates a variety of marker tip configurations wherein the relative lengths of each maximum end width 6 and minimum end width 7 are different for each configuration. For the particular configuration in which the point 8 is positioned quite close to one edge of the exterior surface 3, a maximum marking line width may be obtained from a pointed round tip of a given diameter. It should be noted that while the conical marker end 5 is off-centre with respect to the central longitudinal axis 9, its own conical end axis 12 is, indeed, still parallel to the central longitudinal axis 9. As a result, every end width of conical marker end 5 (including a maximum end width 6, a minimum end width 7 and every end width therebetween) is positioned at an equal angle of inclination with respect to the conical end axis 12. As a practical matter, therefore, this marker tip 1 may be held at the same angle of inclination with respect to a marking surface regardless of the line width being drawn. The user need only rotate the marker tip, and its associated writing instrument, about the tip's central axis 9 until the desired marker surface width is adjacent to the intended marking surface. Drawing the marker tip across the marking surface should then produce a line of the desired width. The maximum end width 6 and minimum end width 7 as shown in Figure 1 are substantially flat surfaces which are completely engaged by a writing surface when used as intended. The off-centre positioning of the conical marker end 5 results in a relatively oval edge 13 being formed at the exterior surface 3 on each end of the marker tip 1. Within such oval edge 13 is both a high edge 19 and a low edge 11 associated with a minimum end width 7 and maximum end width 6, respectively. Again, it must be noted that while Figure l offers both the maximum end width 6 and the minimum end width 7 of the conical marker end 5, there are an infinite number of end widths which exist between these two ends of the spectrum. The marker tip 1 also includes the point 8 for true writing purposes. In conjunction with the instrument in which it is mounted, the marker tip 1 may then be held at a slightly greater, and more desirable, angle with respect to the writing surface. The marker tip may then be used as any other ordinary writing instrument. Figure 2 presents a side view of the marker tip shown in Figure 1 and offers a slightly different perspective on the conical marker ends 5. From this view it can be seen that the maximum end width 6 is defined as that distance between the point 8 and the low edge 11. Similarly, the minimum end width 7 is defined as that distance between the point 8 and the high edge 10. As previously noted, the conical marker end 5 includes an infinite number of radial end widths between the maximum end width 6 and minimum end width 7. The top view of the marker tip shown in Figure 2 also offers the middle end width 14 which is approximately one-half as long as the maximum end width 6 and twice as long as the minimum end width 7. Referring now to Figure 3, an end view of the marker tip shown in Figure 1 is shown whereby the radial position of the point 8 is exemplified with respect to the marker tip's exterior surface 3. The maximum end width 6 and the minimum end width 7 are again defined in Figure 3 with the shaded surfaces representing the various other end widths which are available for marking purposes. Figure 4 presents an alternative embodiment of the present invention wherein its respective maximum end width 21 and minimum end width 22, as well as all other end widths between these two, are slightly convex in shape. This arcuate dimension is denoted by the letter "R" in Figure 4. All other dimensions of the marker tip 2 as shown in Figure 4 are identical to those of the marker tip shown and described in Figure 1, including the point 23, the high edge 24, the low edge 25, the exterior surface 26 and the mounting groove 27. Figure 5 presents a top view of the marker tip 2 where it can be seen that again the maximum end width 21 is defined as that distance between the point 23 and the low edge 25 and the minimum end width 22 is defined as that distance between the point 23 and the high edge 24. This alternative embodiment, wherein the conical marker end 20 includes a slightly convex edge, also includes all end widths which lie between the maximum end width 21 and the minimum end width 22. For example, the top view of Figure 5 shows the middle end width 28 which is approximately one-half as long as the maximum end width 21 and twice as long as the minimum end width 22. Turning now to Figure 6, an end view of marker tip 2 is shown which is substantially identical to the end view shown and described in Figure 3. Indeed, the point 23 is positioned substantially closer to one edge of the exterior surface 26 such that the maximum end width 21, the minimum end width 22 and all other end widths lying therebetween may be formed. The point 23 of the marker tip 2 is intended to have the same size and shape as the point 8 of the marker tip 1 so that the marker tip 2 may also be employed as a true writing instrument. While the present invention has been illustrated in some detail according to the preferred embodiments shown in the foregoing drawing and description, it will be apparent to those skilled in the pertinent art that variations and equivalents may be made within the scope of that which has been expressly disclosed.

Claims: A marker tip (1 or 2) for use in a writing instrument, the marker tip (1 or 2) comprising: an elongate body (3) having a central axis (9) and adapted to be maintained in absorbing relation to a liquid marking medium contained within a reservoir section of the writing instrument, and a marker end (5 or 20) for producing lines of varying width by rotation of the marker tip (1 or 2) about the central axis (9) of the elongate body (3) while maintaining a given angle between the marker tip (1 or 2) and a marking surface, characterised in that the marker end (5 or 20) has a marker surface which is generally conical with a central axis (12) which is generally parallel to and offset from the central axis (9) of the elongate body (3). A marker tip according to claim 1, characterised in that the marker surface terminates in a single point (8 or 23). A marker tip according to claim 2, characterised in that the single point (8 or 23) of the marker end (5 or 20) is operable to produce lines of the marking medium. A marker tip according to any preceding claim, characterised in that in order to produce a line of a single width, a substantially linear shaped portion of the marker surface contacts a marking surface. A marker tip according to any preceding claim, characterised in that the marker surface is slightly convex in shape. A marker tip according to any preceding claim, characterised in that the elongate body (3) of the marker tip (1 or 2) has a substantially circular cross section. A marker tip according to any preceding claim, characterised in that the marker tip comprises a fibrous and porous material. A marker tip according to any preceding claim, characterised in that it has a generally oval intersection between the marker surface and the elongate body.

Inventors: BAUDINO RODNEY J, BAUDINO, RODNEY J.
Applicants: SANFORD CORP, SANFORD CORPORATION
Application year: 1996
Main classification: B43K17
IPC codes: B43K17, B43K1, B43K8