WO1999065706A1

WO1999065706A1 - A writing instrument

Info

Publication number: WO1999065706A1
Application number: PCT/SE1998/001175
Authority: WO
Inventors: Alex Walling
Original assignee: Pulsar Ab
Priority date: 1998-06-17
Filing date: 1998-06-17
Publication date: 1999-12-23
Also published as: AU8360598A

Abstract

A writing and/or drawing instrument includes an instrument body (1) provided with a channel (32) which receives a stylus for axial movement therein. The stylus-accommodating channel (31) is connected laterally to one side surface of the instrument body (1) through the medium of a slot (31) that extends along the channel (32) and has a width which is smaller than the width of said channel (32), such as to form an undercut groove (3). The instrument includes a one-way latching facility (7; 41, 42, 51, 55, 21) that co-acts with the stylus in a manner to prevent the stylus moving backwards along the channel (32).

Description

A writing instrument

The^" present invention relates to a writing and/or drawing instrument of the kind defined in the preamble of Claim 1. 5

It will be understood that the term "writing and/or drawing instrument" as used in this document also includes a mechanical pencil. 0 The invention thus relates to a writing and/or drawing instrument of the kind that contains a so-called stylus which lies in a channel in the body of the instrument and which can be advanced through the channel from one end of the body, for instance as the lead is used in the case of a mechanical lead

15 pencil. When the writing point has the form of a small rotating metal ball as in the case of a ball-point pen or the like, the arrangement is such as to enable the writing point to be withdrawn to a storage position after use.

20 The object of the present invention is to provide a writing and/or drawing instrument of this kind which is of such simple construction as to enable the to be manufactured at low cost.

25 Another object is to provide a construction which enables the writing point or stylus to be readily advanced with one-way latching of the stylus.

Further objects of the invention will be apparent, either 30. directly or indirectly, from the following description.

CORRECTED These objects are achieved with a writing and/or drawing instrument according to the accompanying Claim 1.

Further embodiments of the inventive writing and/or drawing instrument will be evident from the accompanying dependent Claims.

Important advantages with respect to manufacture of the writing and/or drawing instrument are obtained by designing the stylus-accommodating channel so that it is open laterally towards one side surface of the body of the instrument through the medium of a slot whose width is smaller than the width of the channel. The groove provided by the slot and the channel can be formed by injection moulding the body of the instrument with the aid of a mould die that corresponds to the configuration of the groove and that is, for instance, firmly connected to one mould half. Because the body is elastically deformable immediately prior to opening the mould, the die can be easily withdrawn laterally from the undercut groove formed thereby. Another advantage is that the stylus can then be inserted laterally into the channel via the slot. According to the invention, there is also provided a one-way stylus latching facility. A stylus drive means is preferably also fitted to the body of the instrument, so as to enable the stylus to be advanced manually along the channel.

The invention will now be described with reference to exemplifying embodiments thereof and also with reference to the accompanying drawings. Fig. 1 illustrates a writing and/or drawing instrument constructed in accordance with the invention.

Fig. 2 illustrates stylus drive means provided in the writing and/or drawing instrument illustrated in Fig. 1.

Fig. 3 illustrates an inventive writing and/or drawing instrument where the stylus has the form of a ball-point cartridge.

Fig. 4 illustrates another embodiment of an inventive writing and/or drawing instrument.

Fig. 5 is a sectional view taken on the line IV-IV in Fig. 4.

Fig. 6 is a sectional view taken on the line V-V in Fig. 4.

Fig. 7 illustrates from above the embodiment shown in Fig. 4 supplemented with drive means.

Fig. 8 is a sectional view taken on the line VII-VII in Fig. 7.

Figs. 1 and 2 illustrate a writing and/or drawing instrument that includes a body 1 and a groove 3 which extends in the longitudinal direction of the body 1 and opens out at one end 11 of the body 1 and which is also open laterally on one side surface of said body, at least along a part of the length thereof. The groove 3 thus opens out laterally via a slot on one side surface of the body 1. In the case of the embodiment illustrated in Figs. 1 and 2, the groove 3 opens out into a channel 2 which is formed in one side surface of the body 1 and extends along the groove in a longitudinal region of the body 1. The channel 2 has a serrated or toothed side-edge 21. A drive means 4 is shown positioned at the rear end of the channel 2. Lying in the undercut part of the groove 3 is a stylus that can be advanced towards the front end 11 of the instrument with the aid of the drive means 4, said stylus having the form of a pencil lead in the illustrated case. The groove 3 has a flared longitudinal section 5 in the channel 2. As will be seen, the groove has the form of a bore located in the front and the rear parts of the body of said instrument and corresponding to the stylus. The bore also opens out at the rear end of said body.

As will be seen from Fig. 2, the drive means 4 includes a base body 41 whose underside includes a profiled body 42 whose cross-sectional configuration is generally the same as the cross-sectional configuration of the groove 3, i.e. the profiled body 42 has a neck 43 that corresponds to the slot part of the groove 3 that opens out towards the outside of the body 1, and a flared part 44 which is connected to said neck 43 and which corresponds to the undercut part of the groove 3. The drive means can be fitted by inserting the profiled body 42 into the flared or widened section 5 of the groove 3 , the length of this flared section corresponding to the length of the profiled body 42.

The base body 41 also carries a press plate 47 which is inclined slightly upwards from the base 41 and connected thereto via hinge means 48, which may consist of a weakened part of the material at the junction between base 41 and press plate 47.

Provided on the rear end of the base body 41, beneath the press plate 47, is a rearwardly extending, flexible rod 51 which carries immediately behind its rear end-part 52 a laterally and outwardly projecting tooth 5 which in a non- actuated state of the rod 51 meshes with the teeth or serrations 21. The tooth 5 and the teeth 21 are adapted to coact to prevent a pencil lead being drawn back into the groove or bore 3.

The forward free-edge of the press plate 47 carries an arrow- shaped tooth 49 which co-acts with the front part 52 of the rod 51 when the press plate 47 is pressed down, so as to cause the rod 51 to bend laterally outwards in a direction in which the tooth 5 is disengaged from the teeth 21 and therewith allow the drive means to be retracted, for instance to enable a fresh pencil lead to be loaded. The teeth 21 and the tooth 5 enable the drive means 4 and the pencil lead, or stylus, to be advanced without pressing down the plate 47. However, if the plate 47 is pressed down, the user of the writing instrument, or mechanical pencil in this case, is able to move the drive means 4 still more readily along the channel 2 while advancing the stylus, in this case the pencil lead, in the groove 3 so that the tip of the stylus will project from the front end 11 of the instrument body to the extent desired. When pressure on the press plate 47 is removed, the tooth 5 will move back into engagement with the teeth 21 as the rod 51 returns to its initial state by virtue of its resiliency. The part 42 of the drive means 4 that advances the stylus, in this case the pencil lead, also includes means for holding the drive means 4 laterally to the body 1. The drive means 4 can be easily fitted to the instrument body 1, by pressing said drive means 4 laterally against said body, therewith causing the undercut part 42 of said drive means to snap into the undercut groove 3.

The embodiment shown in Fig. 4 also has a laterally open groove 3 that includes a channel 32 for accommodating a pencil lead, and a slot 31 which is narrower than said channel 32 and which opens out on one side of the body 1.

The one-way latching facility is obtained with the aid of one or more resilient tongues 7, where the edge of said tongue or tongues adjacent the groove 3 has a central recess 71 that forms a part of the channel 32, and an edge-part 72 which delimits the slot 31. The embodiment illustrated in Figs. 3-6 includes a plurality of tongues 7 which are disposed opposite one another in pairs such that the ends of each such pair will essentially abut one another, for instance via edge surfaces 73. An important feature of the tongues is that the free end of respective tongues defines an acute angle with the longitudinal axis of the groove. The depth of the groove 7 is restricted, so that the tongue, or tongues, 7 will exert lateral pressure against the stylus 1 in the channel 32. The tongue/tongues 72 generate relatively little friction against the stylus as it is advanced, while generating relatively high friction as the stylus is moved in the opposite direction. As the stylus passes a tongue, the tongue springs in with the edge of the recess 21 behind the end of the stylus and therewith latches the stylus against return movement .

Fig. 8 illustrates an embodiment that includes a drive body 41 that carries a neck 31 corresponding to the slot 31, and a pusher 44 corresponding to the shape of the channel 32. The pusher 44 can be snapped laterally into the groove 3, by virtue of the high resiliency of those parts of the body 1 that border on the slot 31 and the channel 32.

In the case of the Fig. 3 embodiment, the write stylus is an ink cartridge that carries a ball-point or the like at one end. The stylus 11 can be fitted loosely to the drive means, e.g. friction-held, by inserting the end of the stylus into a recess in the body 42. The teeth 21 are restricted to two recesses corresponding to the end positions of the stylus 11/the drive means 4 (the ball-point carried by the stylus is withdrawn into the body and advanced from this position to a position in which it protrudes out from one end of the instrument.

Claims

1. A writing and/or drawing instrument that includes a body (1) having a channel (2) adapted to accommodate a so-called stylus for axial movement therein, characterised in that the channel (31) is connected laterally to one side surface of the body (1) through the medium of a slot (31) which extends along the channel (32) and which has a width that is smaller than the width of the channel (32), such as to form an undercut groove (3); and in that said instrument includes a one-way latching facility (7; 41, 42, 51, 55, 21) adapted for co-action with the stylus such as to prevent said stylus from moving rearwardly along the channel (32).

2. A writing and/or drawing instrument according to Claim 1, characterised in that said one-way latching facility includes one or more resiliently flexible tongues whose one freely movable end is shaped 71, 72 to form a part of said groove, wherein the forward, freely movable end of respective tongues defines an acute angle with the stylus in the direction of forward movement of said stylus, and wherein the freely movable end-edge of a respective resiliently flexible tongue is adapted to move in behind the end of the stylus as the stylus passes said tongue.

3. A writing and/or drawing instrument according to Claim 2 , characterised in that the latching facility includes at least one pair of tongues whose freely movable ends form a respective side of said groove ( 3 ) .

4. A writing and/or drawing instrument according to any one of Claims 1-3, characterised in that a pusher (41, 42) is mounted in the groove (3) behind the stylus; and in that the pusher (41, 42) includes a plate (41) that is exposed on said one side of the instrument body ( 1 ) .

5. A writing and/or drawing instrument according to Claim 1, characterised by a drive means (4) which includes a base plate (41) and an undercut body (2) which is received in the undercut groove (3); in that the base plate is received in an outwardly open channel in the instrument body ( 1 ) wherein the groove (3) opens into the bottom of said channel; in that the channel includes latching teeth (21); in that the drive means includes a latching tooth (5) which is biased into engagement with the teeth (21); and in that the drive means has an actuator (47, 48, 49) which when activated releases engagement of the latch tooth (4) with the teeth (21), thereby enabling the drive means ( 4 ) to be moved forwards for advancement of the stylus.

6. A writing and/or drawing instrument according to any one of Claims 1-5, characterised in that the instrument body (1) is comprised of highly resilient material at least adjacent to the groove (3), such as to enable a stylus to be snapped laterally into the channel (32) via the slot (31).

7. A writing and/or drawing instrument according to any one of Claims 1-6, characterised by a drive means (4) that includes an undercut stylus-pushing body (42) which is inserted in the undercut groove ( 3 ) and shape-bound therein but displaceable therealong.

8. A writing and/or drawing instrument according to Claim 7, characterised in that the material of the pushing body (42) and/or of the groove (3) in the proximity of the instrument body ( 1 ) is highly resilient so as to enable the pusher body (42) of the drive means (4) to be snapped laterally into said groove (3).

9. A writing and/or drawing instrument according to any one of Claims 1-8, characterised in that the stylus has the form of an ink cartridge provided with a writing/drawing tip; and in that the cartridge is connected with a one-way latching means formed as a drive means and capable of being actuated to enable the stylus to be returned to a storage position in said instrument body.