WO1991004870A1

WO1991004870A1 - Material and operability optimizing paper clip

Info

Publication number: WO1991004870A1
Application number: PCT/US1990/005722
Authority: WO
Inventors: Myles M. Walker, Jr.
Original assignee: Walker Myles M Jr
Priority date: 1989-10-05
Filing date: 1990-10-05
Publication date: 1991-04-18
Also published as: EP0494953A1; CA2066032A1; JPH05500007U

Abstract

A paper clip which is formed of a continuous band of material, and comprises an outer clamping frame, an inner clamping frame, and a pair of torsion members. The outer clamping frame is of a substantially triangular gross geometry and has a pair of transverse bridge members and outer clamping portions which extend from the respective transverse bridge members and converge at an outer reinforced tip. The inner clamping frame is also of a substantially triangular gross geometry and has inner clamping portions which converge at an inner reinforced tip. Each torsion member extends substantially perpendicularly from a respective transverse bridge member and continues into a respective contoured section. Each contoured section initially diverges in the direction of a respective outer clamping portion and then converges in a direction towards the inner reinforced tip and continues into a respective inner clamping portion.

Description

Title: MATERIAL AND OPERABILITY OPTIMIZING PAPER CLIP

Field of Invention

The present invention relates generally to the field of pape clips that are often made of plastic wherein an inner clampin member is displaced from the plane of outer clamping limbs in orde to grip a volume of paper therebetween and relates, more particularly, to certain new and useful improvements in such pape clips.

Brief Description of the Prior Art

Figure 1 shows a prior art plastic paper clip of very simple design which operates by transverse bending of its inner clamping member 10 in response to a volume of paper. The design limitations in this apparatus are readily apparent.

One reason that this apparatus is not satisfactorily operable is that the differences between the base/width dimensions of the inner clamping member 10 and the outer clamping limbs 12 are relatively great. It is believed that this promotes instability/infirmness of the grip of the paper clip on the volume of paper.

Second, this apparatus employs a combination of triangular and rectangular geometry in the outer clamping limbs 12. This results in a waste of material with no corresponding gain in utility. Additionally, this paper clip wastes material at tip 14 and transverse bridge members 16. This waste of material is especially damaging to the operability thereof at transverse bridge members 16 where it is believed to render the paper clip critically less flexible and to promote breakage thereof at or about pivot points 18 and 20.

Further, the cross-section of this paper clip is rectangular. This inhibits rotation of the inner clamping porr.ions 22 which occurs during stressing of the paper clip in order to accommodate a volume of paper. It is believed that the rectangular cross- sectional shape causes a critical resistance to rotation and promotes breakage of the inner clamping portions 22 at or about pivot points 18.

Additionally, this paper clip tends to stand off from the volume of paper for the reason that it contains no means to maintain contact of the inner clamping member tip 24 with the volume of paper. Finally, the rectangular geometry of this paper clip imposes a severe limitation on the volume of paper that may be held relative to the size of the paper clip. Since the maximum amount of paper that may be so held is absolutely determined by the distance between inner clamping portions 22 and outer clamping limbs 12 the triangular shape of Fig. 2 is optimal.

Figure 2 shows a prior art plastic paper clip of improved design. Although this apparatus requires approximately the same amount of material to manufacture and is only 20% wider at the base than the apparatus of Fig. 1 it has twice the paper holding capacity. This improved paper clip features a gap between the inner clamping limbs 30 .and the outer clamping limbs 32 that is relatively small.

As will be seen, the primary disadvantage of this paper clip is due to its design which requires the use of a superfluity of material in order to achieve operability. This, in turn causes limitations on its operability and susceptibility to breakage.

In order to maintain contact of the inner clamping member 34 with the volume of paper the paper clip of FIG. 2 employs inner clamping limbs 30 that are not supported at one end 36. The unsupported ends 36 impact the volume of paper and transmit a longitudinally inward force to the supported ends 38 which assists the inner clamping member 34 in maintaining its grip on the volume of paper and in preventing the support member 40 from "standing- off" from the volume of paper.

However, this prior art scheme of using clamping limbs 30 that are not supported at their ends 36 is wasteful, limits operability and at the same time creates a weakness that is vulnerable to snagging and to breakage.

It is wasteful because extra material must be used in order to support the clamping limbs 30 at a location 38 that is distant from the transverse bridge members 42. More importantly, the extra material limits operability by preventing the torsion members 44 from responding torsionally in a grip enhancing manner to the stress of accommodating a volume of paper. This is because the support member 40 contains more material, is more resistant to bending and therefore, during stress, effectively interrupts the transmission of the torsional forces formed on the torsion members 44 to the inner clamping limbs 30.

Because support member 40 interrupts the transmission of the torsional forces, junctures 46 are highly stressed and vulnerable to breakage. In addition, the supported ends 38 are less flexible than the clamping limbs 30 themselves and are therefore, similarly susceptible to breakage. As will be seen, the preferred embodiment solves thes problems by making the torsion members 44 continuous with the inne clamping limbs 30 and forming a substantially closed, reinforced, inner clamping frame (see Fig. 3) . If the inner clamping limbs 3 are supported at a location that is relatively close to th transverse bridge members 42 rather than distant thereto, surprising result occurs. Material is conserved and operability i increased. Thus the preferred embodiment accomplishes its objec of saving material, resisting snagging and breaking and i assisting the inner clamping limbs 30 to bend torsionally as wel as longitudinally toward the volume of paper to give a better gri thereon.

Representative examples of known, prior art plast. c pape clips are illustrated in drawing figures 1 and 2.

These known examples of prior art plastic paper clips ar disadvantageous for several reasons. Principally, however they ar disadvantageous because they do not employ a material/utilit optimizing design. This results in low operability, high cos and/or breakability problems.

It is, therefore, desirable to provide a plastic paper clip that neither imposes a trade-off between utility and economy no breaks under normal use conditions.

In accordance with the present invention, an improved paper clip is provided which costs substantially less to manufacture than the prior art while offering superior operability and resistance to breakage.

Summary of Invention

In general the present invention concerns a paper clip which is formed of a continuous band of material, and comprises an outer clamping frame, an inner clamping frame, and a pair of torsion members. The outer clamping frame is of a substantially triangular gross geometry and has a pair of transverse bridge members and outer clamping portions which extend from the respective transverse bridge members and converge at an outer reinforced tip. The inner clamping frame is also of a substantially triangular gross geometry and has inner clamping portions which converge at an inner reinforced tip. Each of the torsion members extends substantially perpendicularly from a respective transverse bridge member and continues into a respective contoured section. Each contoured section initially diverges in the direction of a respective outer clamping portion and then converses in a direction towards the inner reinforced tip and continues into the respective inner clamping portion.— Brief Description of the Drawings

Figure 1 is a pictorial representation of a prior art paper clip.

Figure 2 is a pictorial representation of a another prior art paper clip.

Figure 3 is a pictorial representation of the preferred embodiment of the present invention.

Figure 4 is a side view of the preferred embodiment as it would appear if it were holding a volume of paper.

Figure 5 is a rear view of the preferred embodiment as it would appear if it were holding a volume of paper.

Figure 6 is a frontal view of the preferred embodiment as it would appear if it were holding a volume of paper.

Detailed Description of the Preferred Embodiment

Fig 3 shows a paper-clip 49 which is constructed in accordance with the present invention and preferably made from plastic. The paper-clip is manufactured in the form of a predominantly closed frame of substantially triangular configuration.

An inner clamping frame 50 that is continuous with inner torsion members 52 solves the problems of breakage, of excess use of material and of the interruption of the transmission of torsional force that are present in the prior art. Thus the present invention actually uses less material than the prior art to achieve superior operability and resistance to breakage. This is both a surprising and remarkable result. When the paper clip 49 is in its stressed state torsional forces are thereby set up in torsion members 52 that act directly on an inner clamping frame 50 via contour areas 54 and urge the contour areas in an inward direction and thus enhance the grip of the paper clip 49 on the volume of paper.

Consistent with the material minimizing object of the present invention, the paper clip 49 of the present embodiment is constructed of one continuous band of material. In addition, material that is needed to achieve an operable result is conserved by dispensing with the inner support member 40 of Fig. 2 entirely. It is believed that this saving in material will result in a reduction in manufacturing cost of between 25 to 35%, a significant figure. In detail, the paper clip 49 has two outer clamping limbs 56 which converge in the center at a reinforced junction 57. The ends of the outer clamping limbs which are remote from the reinforced junction 57 merge into transverse bridge members 58 which are likewise reinforced.

The torsion members 52 extend at right angles to the transverse bridge members 58 into the interior space formed in the paper-clip 49 between the outer clamping limbs 56 and the transverse bridge members 58. The transverse bridge members 58 are in alignment with each other when in the unstressed state and are separated by a slot 59 which is formed by the torsion members 52 in the center thereof, so that an inner clamping member 61 is comprised of two torsion members 52 which are initially, substantially parallel but which then alternately diverge and converge to form an inner clamping frame 50 which is reinforced at its tip 60.

The ends of the two torsion members 64 directed towards the junction 57 form contoured sections 54 which initially diverge in the direction of the outer clamping limbs 56 and then converge, forming vertices 66 thereby, to meet at the tip 62 that is reinforced and therefore resistant to bending. The inner clamping frame 50, formed thereby, is relatively long in the direction of inner clamping limbs 68 and, at its widest is almost the full width of the two transverse bridge members 58. Although the inner clamping frame 50 is resistant to bending, so that its shape is not impaired by the torsional forces acting upon the torsion members 52, it is still able to transmit the torsional forces in a grip enhancing manner. In other words, the inner clamping frame 50, forms a substantially closed V which lies in the same position within the V formed by the outer clamping limbs 56 and subtends a substantially identical angle.

Figs. 4 to 6 show the paper-clip 49 after it has been applied to a volume of paper. The outer clamping limbs 56 and the torsion members 52 thus act as combined torsion and bending springs by virtue of the fact that they endeavor to return from their displaced position, shown in Fig. 5 to the position in which all parts of the paper-clip are in one plane. Thus, as may be seen in Fig. 6, the torsion members 52 are greatly torsioned. The inner clamping frame 50 does not hinder the torsion, but rather allows the grip-enhancing transmission thereof in the region of the contoured sections 54. In addition, the contoured sections 54 are located in the vicinity of the edge 70 of the volume of paper (Fig. 4 ) , so that "standing off" of the inner clamping frame 50 is also prevented. The longitudinal bending resistance of the clamping frame 50, thus achieves a good clamping effect on the top of the volume of paper and at the same time ensures that the outer clamping limbs 56 abut satisfactorily against the bottom of the volume of paper.

Claims

I claim:

7. A paper clip formed of a continuous band of material comprising: an outer clamping frame of a substantially triangular gross geometry and having a pair of transverse bridge members and outer clamping portions which extend from said respective transverse bridge members and converge at an outer reinforced tip; an inner clamping frame of a substantially triangular gross geometry and having inner clamping portions which converge at an inner reinforced tip; and a pair of torsion members, each extending substantially perpendicular from said respective transverse bridge members and continuing into a respective contoured section, each said contoured section initially diverging in the direction of said respective inner clamping portions and then converging in a direction towards said inner reinforced tip and "and continuing into said respective inner clamping portion.

8. The paper clip of claim 7, wherein the length of each said transverse bridge member is approximately equal to the length of said torsion members.

9. The paper clip of claim 8; wherein each said inner clamping portion is substantially parallel with said respective outer clamping portions.

10. The paper clip of claim 9; wherein the length of each said transverse bridge member is substantially equal.

11. The paper clip of claim 10, wherein the length of each said contoured section is substantially equal.