GB2130530A - A resilient element for a ball pen retracting mechanism - Google Patents

Abstract

A resilient element (1) for a ball point pen retracting mechanism is elongate and is provided with transverse notches (7) situated one opposite the other in staggered arrangement, and serves as a structural element incorporated into an axially arranged mechanism for extending and retracting a refill of a pen. The invention may be utilised for new designs of ball pens and also as an adapter element for existing ball pens. <IMAGE>

Description

SPECIFICATION Resilient element of a motion mechanism of a ball pen The invention relates to a resilient element of a motion mechanism of a ball pen.

Known motion mechanisms of ball pens have been designed without resilient elements.

The writing function of a ball pen resides in principle in the fact that a ball freely rotating in a socket of a writing point transports ink from a reservoir onto paper. Rotation of the ball is therefore a necessary condition for writing. For the ball to rotate, its friction on the writing surface, e.g. paper, must be greater than its friction in its socket inside the writing point; as its friction in the socket of the point is practically constant, whereas its friction on paper is directly proportional to the force applied to the ball pen during writing, it is evident that there exists some minimum force, which must be exerted on the ball pen for the ball to rotate and to write reliably.The smaller the minimum force needed, the smoother the writing; the pen also writes more softly, slides better, the writing is less tiresome and the pen is classified as a product of high quality.To achieve such quality advantages various means are used: to achieve a low friction of the ball in the socket a ball is used which is made of a very smooth and hard material, e.g. austentic steel, sapphire, corundum, carbide, tungsten or a suitable sintered carbide, which also increases the service life of the ball and its shape permanency, or the ball socket is made of a very hard and smooth material.

In order to increase the friction of the ball on paper and to transport the writing ink on paper more effectively, balls having a porous surface are used. To facilitate the flow of ink, inert gas under pressure may be introduced into the ink reservoir and in this way the ink is forced out in sufficient quantity.

All these measures do not solve the main physiological factor of writing, which affects the course of the force exerted on the pen and, in this way, the hand fatigue when writing: as the pen is moved towards the writing person it is gradually erected with respect to the paper, the point of holding the pen moves up, and if the refill is stiffly fixed in the ball pen, it transmits the pressure of the hand directly, and in this way the vertical component of the force exerted by the hand and consequently the pressure acting on the writing surface, increase - and that is the main factor which causes the fatigue of the hand during writing as well as the subjective feeling that the writing is tiresome, that the pen does not slide sufficiently smoothly, etc.

The principle resides in the fact that for controlling the increased vertical pressure or resistance during writing, the pen must be more tightly pressed by fingers, whereby the hand becomes more tired. As the pen is erected so are the fingers, which increases fatigue due to the tightening of tendons.

The economic aspect of the attaining of the desired properties in ball pens and also the removal of undesirable concomitant phenomena when writing with ball pens is solved with success - as proved by tests - by a resilient element in the motion mechanism of a ball pen according to the invention, the resilient element being of substantially elongate shape,with a cross-section of arbitrary shape along its length and provided on its surface, especially at one of its ends, with at least two notches situated one against the other in a staggered arrangement.

The progress achieved by the invention resides in the existence of a new resilient element, which reduces physical effort when writing with a ball pen.

Advantages of the invention reside also in the design of the resilient element, which enables the element to be used as a structural element in motion mechanisms of future design, but also as an adapter element for existing designs, which will acquire with this element new qualities and properties. The chosen design of the element enables its location in any piace in the functional mechanism of the ball pen and its application as an adapter element for hitherto known mechanisms, which requires only minor structural adaptations of existing parts.

In order that the invention may be clearly understood and readily carried into effect, a preferred embodiment is, by way of example, hereinafter more fully described and illustrated in the accompanying diagrammatic drawings, in which: Figure 1 shows a partial longitudinal section of a shaped resilient element situated in the refill; Figure 2 shows a partial longitudinal section of the resilient element situated between the first member of the motion mechanism and the refill; Figure 3 shows a partial longitudinal section of a seating of the resilient element between the first and second members of the motion mechanism; and Figure 4 shows a partial longitudinal section of the resilient element and its seating between the upper part of the pen body and the second member of the motion mechanism.

The resilient element according to the invention is in fact a structural element,which may be advantageously used both for newly designed ball pens and as an adapter element for known ball pens, requiring only smail adaptations of glands of the covers of refills of various makes, or of members of motion mechanisms for extending and retracting of existing design; the resilient element accord ing to the invention may be incorporated into the motion mechanism of the ball pen, which is so arranged that all its elements are situated one behind the other in the body of the ball pen, at any place either between the refill and an arbitrarily shaped member of the motion mechanism, or between some functional members of the motion mechanism, but also at the end of the motion mechanism between the upper end of the inner surface of the upper part of the body and the last member of coaxially arranged members of the motion mechanism.

The illustrated resilient element 1 is made in one piece of plastics, e.g. by compression moulding or injection moulding, and is of a substantially elongate shape of an arbitrary cross-section,the surface of which, especially at one of its ends, is provided with at least two transverse notches 7 extending from opposite sides in staggered arrangement. The illustrated resilient element 1 is tubular and has notches 7 in staggered arrangement extending transversely through more than half of its cross-section.

In agreement with the above-mentioned possibilities of location of the resilient element in the ball pen, the element 1, shown in Fig.

1, forms the first member of the motion mechanism and also, a cover or a packing of a refill 2. Analgously, according to Fig. 2, the resilient element 1 is situated as a functional member between the refill 2 and the first member 4 of the motion mechanism. According to Fig. 3, the resilient element 1 is situated between the first member 4 and the second member 3 of the motion mechanism and provides only the function of an elastic seat for the refill 2 in contact with the writing surface.According to Fig. 4, the resilient element, having the function of an elastic seat for the refill 2 in contact with the writing surface, is situated in the upper part 6 of the body, where it leans against the inner surface of the upper part 6 of the pen body by one of its ends, and by the other one it leans against the second member 3, which together with a first bumper member 4 is situated in the third member 5 of the motion mechanism fixed in the upper part 6 of the body.

If the element 1 is used as a gland, or as a cover of the refill 2, or simultaneously as a cover and functional element of the motion mechanism, the element 1 is provided in the end adjacent the refill, with a venting system (not shown), the design of which is determined by the design of the refill 2.

The notches 7 in the element 1 may be situated, in dependence upon the design of the motion mechanism, either perpendicularly to the longitudinal axis of the element 1, or at an angle thereto, both in vertical direction and also in a direction horizontal to the longitudinal and vertical axis of the element.

The resilient element 1 provides primarily the function of an elastic contact of the ball of the refill 2 with the writing surface possibly together with the function of some of the elements of the motion mechanism of the ball pen.

In this specification the term "ball pen" is intended to include any writing or drawing implement in which a freely rotatable ball deposits an ink trace, and "ink" is intended to include any material transmitted by said ball on a surface in order to deposit a trace.

Claims (8)

1. A resilient element of a motion mechanism of a ball pen, which is of a substantially elongate shape with a cross-section of arbitrary shape along its length, provided with at least two transverse notches situated one opposite the other in a staggered arrangement.

2. A resilient element according to Claim 1, wherein the notches extend through more than half of its cross-section.

3. A resilient element according to Claim 1 or 2, wherein the notches are provided at one end of the element.

4. A resilient element according to any one of Claims 1 to 3, wherein the element is substantially tubular.

5. A resilient element according to any one of Claims 1 to 4, wherein the element is made of plastics.

6. A resilient element according to any one of Claims 1 to 5, wherein the notches extend substantially at right angles to the axis of the element.

7. A resilient element constructed, arranged and adapted to operate substantially as herein described with reference to, and as shown in, the accompanying drawings.

8. A ball pen incorporating a resilient element according to any one of Claims 1 to 7.