WRITING INSTRUMENT WITH ILLUMINATING DEVICE

Abstract: A writing instrument comprises a casing (10) within which is disposed a ball point and ink reservoir unit (22) and a light unit including a bulb (13) and a battery cell (12). The ball point and reservoir unit (22) is provided at one end of the casing (10) and the light unit at the other end. The bulb and reservoir are arranged axially within the casing and are disposed in an axially non-overlapping manner. A portion of the casing between the writing end of the casing and the bulb and containing the reservoir unit is capable of transmitting light from the bulb axially along the casing to the writing end from which the light emerges.

Description: TITLE:* Writing instrument with illuminating device This invention relates to writing instrument more especially ball point or felt tip pens and its object is to provide the pen with an illumination facility. It is often necessary or desirable to use a pen or pencil in poor light conditions. Usually one has to hold a torch in one hand whilst writing with the other. Ideally therefore, a combination of a pen and light would be desirable especially for use by drivers of vehicles or by journalists. Such an arrangement has been disclosed in U.K. Patent No. 1,000,619. However, the invention described therein relies on the essential feature of a centre hole electric light bulb through which the ink reservoir passes. The necessity to provide a bulb of this kind is undesirable in that such bulbs are not readily available on the market and the switching mechanism is relatively complicated thereby involving high manufacturing costs. An object of the present invention is to provide a combination writing instrument and light which avoids the disadvantages of the prior art arrangement. According to the present invention a writing instrument comprises a casing within which is disposed an elongated writing medium and a light unit including a bulb and a battery cell, characterized in that the writing medium is provided at one end of the casing and the light unit at the other end, said bulb and elongated writing medium being disposed in an axially non-overlapping manner, a portion of the casing between the writing end of the casing and the bulb and containing the writing medium, being capable of transmitting light from the bulb axially along the casing to the writing end from which the light emerges. The writing medium may be in the form of a ball point and reservoir unit, a felt or fibre tip and reservoir unit, or a pencil lead. In a preferred construction the portion of the casing is a tube of clear transparent plastics material which is illuminated by the bulb. In the case of a retractable type pen the energising of the bulb may be effected by the same operation as that required for projecting the ball from the casing. In a retractable or non-retractable pen a separate switch may be provided. The invention will be further described by way of example with reference to a non-retractable type pen illustrated in the accompanying drawings in which:- FIGURE 1 shows a section of a first embodiment comprising a ball point pen in which the casing is formed with a removable cap shown in a stowed position which serves to protect the ball point when not in use, and FIGURE- 2 shows a section of a second embodiment in which a removable cap is provided having a pocket clip formed thereon. In the construction shown in Figure 1 the pen comprises a casing 10 having a first portion 10a in the form of a thin-walled moulding of opaque plastics material and a second portion 10b as a block of transparent plastics material attached to the first portion 10a by means of a screw threaded connection 11. The first portion contains a battery cell 12 and a bulb 13 urged together by an electrically conductive spring 14 seated on an end cap 15 fitted into the end of the first portion 10a. A switch button 16 has a part 17 extending through the wall of the first portion, said part 17 being connected to an elongated slider contact 18 which makes electrical contact with a conductive metal holder 19 into which the bulb 13 is screwed thereby to complete the circuit between the battery and the bulb via the spring 14. The second portion 10b of the casing 10 is formed with a bore 20 of a diameter sufficient just to accommodate the ink reservoir 21 of a replaceable ball point pen 22 which in the example shown is placed within the bore from the exterior of the second part. Replacement from the interior may be possible with suitable modification. At the end remote from the ball point the bore 20 merges with a f usto-conical counter-sink 2-3 which accommodates the head of the bulb 13. The reservoir 21 and the bulb 13 are arranged within the casing axially thereof and essentially in an axially non-overlapping manner. In this manner standard light bulbs and ink reservoirs may be used and easily replaced. At the ball point end of the second portion 10b the casing is shaped with a squared-off flat end light emission surface 24 having a diameter of about 1/4 to 1/2 (preferably 1/3) of the overall diameter of the casing, said flat surface 24 being contiguous with a curved surface in the form of the frustum of a dome. When the bulb is switched on the light therefrom is transmitted axially of the casing through the transparent plastics and emerges from the flat surface 14 with a concentrated circular beam 26 and from the domed surface with a ring 27 of less intensity than the circular beam 26. If desired the exterior of the second portion 10b may be coated to ensure internal reflection of the light beam as it travels along the body of transparent plastics. A cap 28 which may be stowed on a reduced diameter portion of the end cap 15, can be placed over the ball point for protection thereof. In the example of Figure 1 the first portion 10a of the casing is formed with a pocket clip 29 whereas in the example shown in Figure 2 the clip 29 is integrally formed on a removable cap 30 which may be placed over the ball point for protection thereof. The switch mechanism in the second example differs in that the slider contact 18 may be moved axially by a press button 31 acting against the spring 14. Means (not shown) may be provided to give a toggle action permitting on and off switching with successive depressions of the push button 31. Alternatively the press button may be provided with means by which on twisting the button the latter remains in an 'on' position until a twisting action in the opposite direction is effected. Any one of the embodiments may be modified to be retractable so that when the button (16, 31) is pressed the pen is ejected at the front end and at the same time the bulb is switched on.

Claims: CLAIMS : • 1. A writing instrument comprising a casing, within which is disposed an elongated writing medium and a light unit including a bulb and a battery cell, characterized in that the writing medium is provided at one end of the casing and the light unit at the other end, said bulb and elongated writing medium being disposed in an axially non-overlapping manner, a portion of the casing between the writing end of the casing and the bulb and containing the writing medium, being capable of transmitting light from the bulb axially along the casing to the writing end from which the light emerges. 2. A writing instrument as claimed in claim 1, characterized in that said portion of the casing comprises a block of transparent plastics material having a bore therein accommodating the writing medium. 3- A writing instrument as claimed in claim 2, characterized in that said block is attached to the portion of casing containing the light unit by a screw threaded connection. 4. A writing instrument as claimed in claim 2, characterized in that said block is formed at the writing end with a squared-off flat end light emission surface. 5. A writing instrument as claimed in claim 4, characterized in that said block is formed at the writing end with a curved surface in the form of a frustum of a dome contiguous with said flat end surface. 6. A writing instrument as claimed in claim 2, characterized in that the bore at the end remote from the writing end is provided with a counter-sink which accommodates the head of the bulb. 7. A writing instrument as claimed in claim 3, characterized in that the light unit includes a spring urging the battery cell into contact with the bulb when the two portions of the casing are screwed together. 8. A writing instrument as claimed in claim 1, characterized in that switch mechanism is provided within the casing operable by a push button arranged exteriorly of the casing. 9. A writing instrument as claimed in claim 1 , wherein the writing medium is a ball point and ink reservoir unit.

Inventors: HARRISON STUART MALCOLM, HARRISON, STUART, MALCOLM
Applicants: HARRISON STUART MALCOLM, HARRISON, STUART, MALCOLM
Application year: 1986
Main classification: B43K29
IPC codes: B43K29