GB2209500A

GB2209500A - Ring binder mechanism

Info

Publication number: GB2209500A
Application number: GB8821121A
Authority: GB
Inventors: Lewis Cohen
Original assignee: Individual
Current assignee: Individual
Priority date: 1987-09-08
Filing date: 1988-09-13
Publication date: 1989-05-17
Also published as: GB8821121D0

Abstract

A ring mechanism for a loose-leaf binder with ring elements (3) secured to carrier rails (20, 21) within a cover rail (2) is modified in that the cover rail is provided with a longitudinal indentation (4) which provides increased strength and rigidity to the mechanism. <IMAGE>

Description

RINJ MECEANISÇ; Background of the Invention This invention relates to a ring mechanism for loose-leaf binders and the like.

There are a variety of known loose-leaf paper ring mechanisms. Common to these mechanisms is the provision of elements forming the ring. The elements extend outwardly from carrier rails. The carrier rails are located within the cover rail. The ends of the ring elements are attached to the carrier rails. The ring elements extend outwardly through apertures in the cover rail and in most known mechanisms form a generally circular shape when in the closed position. In the cover rail the two carrier rails are positioned in a side by side relationship under compression against each other. The action of opening the elements moves the carrier rails in an arc through the centre position with the carrier rails meeting resistance from the cover rail as they trace the arc. The cover rail, being deflected, provides the tension on the ring elements.In most known mechanisms, the cover rail of the ring mechanism undergoes flexing and bending during the opening and closing of the ring element. The ring elements become prone to opening inadvertently resulting in spillage and possible damage to the binder contents.

Brief Summary of the Preferred Embodiment of the Invention The present invention is concerned with a ring mechanism that will provide increased ring element tension and increased overall strength and rigidity. The preferred embodiment of the present invention is characterized by a longitudinal indentation in the cover rail of the ring mechanism.

According to the present invention, there is provided a cover rail formed from sheet material and comprising: an elongate top section having a longitudinal axis and having an indented part and plain parts at either end of the indented part; side edge portions generally parallel to one another and to said longitudinal axis and each extending at an angle to the top section; an indentation in the top section having a generally constant cross-section and extending generally parallel to a longitudinal axis thereof whereby the lateral stiffness between said side edge portions is increased and the cover rail is strengthened; a plurality of paired-apertures in the cover rail transversely opposed from the longitudinal axis of the top section; and a plurality of openings in the top section for receiving fasteners.

According to another aspect of the present invention, there is provided a ring mechanism which comprises: a cover rail formed from sheet material having an elongate top section with a longitudinal axis and having an indented part and plain parts at either end of the indented part, side edge portions generally parallel to one another and to said long-axis and each extending at an angle to the top section, an indentation in the top section having a generally constant cross-section and extending generally parallel to a longitudinal axis thereof whereby the lateral stiffness between said side edge portions is Increased and the cover rail is strengthened, a plurality of paired-apertures in the top section transversely opposed from the longitudinal axis of the top section and a plurality of openings in the top section for receiving fasteners; first and second carrier rails positioned between the side edge portions of the cover rail in a side by side relationship with the carrier rails being greater in combined width than the distance between the side edge portions when the cover rail is unstressed, whereby the carrier rails may be moved from an open over centre position to a closed over centre position; at least one pair of first and second ring elements which are mounted on the first and second carrier rails respectively, which extend through respective apertures in the cover rail, and which include complementary mesh ends which mesh with one another and define a closed loop when the carrier rails are in the closed over centre position, and the mesh ends of the first and second ring elements being spaced from one another when the carrier rails are in the open over centre position.

The interaction between the indented and plain parts of the cover rail can reduce the amount of flexing in the cover rail, or increase its stiffness, thereby increasing the compressive force on the carrier rails. As a result, the opening tension of the ring elements is increased. Increasing the opening tension of the ring elements provides a ring mechanism which is less likely to open inadvertently thereby spilling the binder contents.

In addition, the indentation can increase the longitudinal bending resistance of the ring mechanism. The span between the mounting means of the ring mechanism would normally allow the cover rail to bend and flex, possibly resulting in distortion. The cummulative effect of this distortion is an overall degradation in the durability of the ring mechanism.

However, the indentation effectively eliminates the resultant bending and flexing by increasing the longitudinal bending resistance without adding to the weight of the ring mechanism.

Further, the increased stiffness introduced by the longitudinal indentation aids in the manufacturing process. The side edge portions of the cover rail are not affected by the "snap-back" action of the curved portion of the cover rail. The side edges come out parallel and at an angle of ninety degrees to the horizontal plane in the initial stamping of the cover rail.

The uniformity of the side edge portions benefits the subsequent assembly stages. The forming of the side edge portions over the carrier rails can be more accurately controlled resulting in consistent and improved ring element tension.

Finally, the increased longitudinal resistance of the cover rail resulting from the longitudinal indentation decreases the likelihood of damage occurring to the ring mechanism dur-ing shipping and storage.

Brief Description of the Drawings Further details of the embodiment of the present invention are explained below with the help of the examples illustrated in the attached drawings in which: Figure 1 is a perspective view of a ring mechanism according to the present invention; Figure 2 is a sectional view of the ring mechanism of Figure 1 along the line 2-2, showing the mechanism in a closed position; Figure 3 is a sectional view, similar to Figure 2, showing the complete rings in an open configuration; Figure 4 is a perspective view of one end of the cover rail of the mechanism, as originally formed; and Figure 5 is a sectional view along line 5-5 of Figure 4.

Description of the Preferred Embodiment of the Invention The ring mechanism is denoted by the reference 1 and includes a cover rail 2, ring elements 3 and triggers 7. The cover rail 2 is provided with an indentation 4 extending along its longitudinal axis. The cover rail 2 also includes paired apertures 5 for the respective ring elements 3 and openings 6 for receiving fasteners.

The cover rail 2 has a central top section 29, and side edge portions 30. As shown in the sectional view of Figure 2, first and second carrier rails, 20 and 21 respectively, are held in position by the inwardly turned side edge portions. The outside edges 26, 27 of the first and second carrier rails 20, 21 are positioned inside the inwardly turned side edge portions 30 of the cover rail 2. The inside edges 28 of the carrier rails abut against each other along their entire length, and in known manner are shaped to be held in engagement with one another. The combined width of the carrier rails 20, 21 in the side-by-side position is greater than the distance between the inwardly turned edge portions 30 of the cover rail 2.This results in the first and second carrier rails 20 and 21 being held in compression by the inwardly turned edge portions 30 of the cover rail 2. The force on the outside edges 26, 27 of the first and second carrier rails 20, 21 respectively, exerted by the inwardly turned edges side portions 30 of the cover rail 2 results in the carrier rails 20, 21 being compressed into the over centre position shown in Figure 2.

In known manner, by actuating the triggers 7 or ring elements 3, the ring elements can be moved from the closed position of Figure 2 to the open position of Figure 3 and back again. As shown in Figure 3, in the open position, the inner edges 28 abut the indentation 4, thereby limiting the amount of opening. Each carrier rail 20, 21 has semicircular cut outs in its inner edge 28, so that it does not interfere with the depresed parts including openings 6.

As shown in Figure 1, the ring mechanism 1 is provided, in known manner, with triggers or boosters 7. The triggers 7 are mounted in the ends of both the first and second carrier rails 20 and 21. The triggers 7 provide a lever action which facilitates the opening and closing of the ring elements 3 under the increased ring element tension.

Figure 4 shows one end of the cover rail 2 as initially stamped from sheet steel. The cover rail 2 includes a rectangular recess 12 for receiving a trigger 7. Similarly, notches 14 are provided at the junctions between the top section 29 and side edge portions 30, so that when the side edge portions 30 are compressed rounded corners are provided. When the edge portions 30 are compressed and turned in, in known manner, pivot spigots of the triggers 7 are pivotally held between the cover rail 2 and carrier rails 20, 21. The trigger 7 also engages the carrier rails 20, 21, so as to be capable of deflecting them up or down.

This and other aspects of the construction can be .conventional and are not described in greater detail. As also shown, the indentation 4 extends longitudinally in an indented part 16 of the cover rail 2, with two (one visible in Figure 4) plain or non-indented parts 18 being provided at either end of the indented part 16.

With reference to Figure 1, the ring elements 3 consist of first and second ring elements 22 and 23. The ring elements 22 and 23 extend outwardly through respective apertures 5 in the cover rail 2. In the closed position the ring elements 22 and 23 form a closed loop. The second ends of the ring elements 22 and 23 consist of complementary mesh ends which mesh together when the ring elements 22 and 23 are in the closed position.

As shown in Figure 2, the first end 24 of the first ring element 22 is secured or carried by the first carrier rail 20.

Similarly, the first end 25 of the second ring element 23 is secured to the bottom of the second carrier rail 21. The first ends 24, 25 of the ring elements 22, 23 respectively are secured by flattening their ends against the bottom of the carrier rails 20, 21. In the alternative, the first ends 24, 25 of the ring elements 22 and 23 could be welded to the bottom of their respective carrier rails 20 and 21.

With reference to the perspective view in Figure 1, the longitudinal indentation 4 extends along the longitudinal axis of the top section of the cover rail 2 between the two end pairs of ring elements 8 and 9 and through the other pair of ring elements 10. As shown in Figure 2, the indentation is arcuate when viewed along the longitudinal axis. The indentation 4 is concave when viewed from above. When viewed in section the indentation 4 forms a semi-circular shape. The smooth radial transformation from the top section 29 of the cover rail 2 to the semi-circular depression of the indentation 4 results in an increase in the lateral rigidity of the cover rail with a uniform distribution of the internal forces on the cover rail 2.

The longitudinal indentation 4 is located in the top centre position of the cover rail 2 as shown in Figure 2. As shown in Figure 1, the longitudinal indentation 4 has spherical ends. The spherical ends result in an even distribution of the forces resulting from the deflection experienced during the opening and closing of the ring sets 3. The spherical ends increase the rigidity to the cover rail 2 in both the lateral and longitudinal directions.

The longitudinal indentation is located in the top centre position of the cover rail 2 as shown in Figure 2. With reference to Figure 1, the longitudinal indentation 4 is situated in the top centre of the top section 29 of the cover rail 2 between the openings 6 adjacent to its ends.

Mounting elements 32 are secured in the openings 6. In known manner, the mounting elements, which are short hollow cylinders, enable the mechanism 1 to be secured to a binder cover or the like. The ring mechanism 1 is fastened to a binder cover by passing fasteners, e.g. rivets, through the opening 6 and mounting elements 32 in the cover rail 2. The fasteners pass through the respective openings 6 and are attached to the binder cover.

The longitudinal indentation 4 in the top section 29 of the cover rail 2 increases the compressive force exerted by the inwardly turned edge portions 30 of the cover rail 2 on the carrier rails 20, 21. The cover rail 2 is made of a resilient metal. The outside edges 26, 27 of the first and second carrier rails 20, 21 apply equal and opposite forces to the junctions between inwardly turned edge portions 30 and the top section 29.

This results in lateral deflection of the cover rail 2. During movement between the closed configurations of Figure 2 and the open configuration of Figure 3, this deflection in the cover rail 2 increases as the compressed carrier rails 20 and 21 move through an intermediate configuration. The maximum deflection occurs when the carrier rails 20 and 21 are parallel and in the horizontal position. The longitudinal indentation 4 increases the lateral rigidity of the cover rail 2, and thus the amount of flexing of the cover rail 2. This results in an increased compressive force on the carrier rails 20 and 21 and the load required on the triggers 7. The longitudinal indentation 4 can thereby effectively increase the ring element opening tension by approximately 12.5%.

The indentation 4, also increases the longitudinal bending resistance of the cover rail 2 and the entire ring mechanism 1. In use, when attached to a binder cover, there, is a substantial distance between the mounting points of the openings 6. This span allows the whole mechanism 1 to flex, resulting in distortion, which in turn affects the durability and reliability of the whole mechanism. The indentation 4 increases the rigidity and stiffness of the cover rail 2, and thereby should reduce distortion etc.

After manufacture of the ring mechanisms, they are frequently shipped in bulk, prior to final assembly in binder covers etc. Usually, the mechanisms are shipped in cartons. As a consequence, the pressure of the mechanisms on one another can result in denting and distorting, particularly to the cover rail 2. The extra strength provided by the indentation 4 should alleviate this problem.

As shown in Figure 5, during production, the cover rail 2 is initially stamped from sheet metal and shaped with the side edge portions extending parallel to one another, these side edge portions being denoted 30a in Figure 5. For conventional cover rails or housings 2, the resiliency causes the side edge portions to snap back after stamping. This results in the side edge portions splaying outwards slightly and at an angle greater than 0 90 to a horizontal plane. The indentation 4 helps ensure accuracy of the side edge portions 30. This is a major benefit for subsequent assembly. It ensures the corner rails 20, 21 are accurately placed and positioned, so as to ensure accuracy of dimensions after crimping or bending of the side edge portions 30. Consequently, there should be uniform tension in the ring elements 3 amongst different mechanisms 1.

Whilst a preferred embodiment of the. invention has been described, it will be appreciated that many different varilations of the invention are possible. Thus, whilst the mechanism has been shown with circular rings, many different ring profiles could be employed. Thus, the rings could be oval, elliptical, rectangular and D-shape. The exact mounting of the lower ends of the rings to the carrier rails could similarly be varied.

With regard to the profile and positioning of the indentation, this similarly could be varied. The indentation need not be semi-circular, but could have a variety of profiles, for example rectangular or triangular. The indentation does not have to be located at the top of the mechanism, nor does it need to be strictly parallel to the axis of the mechanism. There could be two or more ipdentations. Thus, for example, there could be two parallel indentations located symetrically on either side of the cover rail. The shape and positioning of each indentation should be chosen to give the desired stiffening effect.

Claims

I CLAIM:

1. A cover rail for a ring mechanism formed from sheet material and comprising: an elongate top section having a longitudinal axis and having an indented part and plain parts at either end of the indented part; side edge portions generally parallel to one another and to said longitudinal axis and each extending at an angle to the top section; an indentation in the top section having a generally constant cross-section and extending generally parallel to a longitudinal axis thereof in the indented part, whereby the lateral stiffness between the side edge portions is increased and the cover rail is strengthened; a plurality of paired apertures in the cover rail transversely opposed from the longitudinal axis of the top section; and a plurality of openings in the top section for receiving fasteners.

2. A cover rail as claimed in claim 1, wherein the indentation extends along the longitudinal axis and is arcuate when viewed along the longitudinal axis.

3. A cover rail as claimed in claim 2, wherein the indentation is semi-circular in section.

4. A cover rail as claimed in claim 1, 2 or 3, wherein the indentation is concave when viewed from above.

5. A cover rail as claimed in claim 1, 2 or 3, wherein the indentation has spherical end portions.

6. A ring mechanism for mounting on a loose-leaf binder, the ring mechanism comprising: a cover rail formed from sheet material having an elongate top section with a longitudinal axis and having an indented part and plain parts at either end of the indented part, side edge portions generally parallel to one another and to said longitudinal axis and each extending at an angle to the top section, an indentation in the top section having a generally constant cross-section, extending generally parallel to a longitudinal axis thereof in the indented part, whereby the lateral stiffness between the side edge portions is increased and the cover rail is strengthened, a plurality of paired-apertures in the cover rail transversely opposed from the longitudinal axis of the top section and a plurality of openings in the top section for receiving fasteners; first and second carrier rails positioned between the side edge portions of the cover rail in a side by side relationship with the carrier rails being greater in combined width than the distance between the side edge portions when the cover rail is unstressed, whereby the carrier rails may be moved from an open over centre position to a closed over centre position; at least one pair of first and second ring elements which are mounted on the first and second carrier rails respectively, which extend through respective apertures in the cover rail, and which include complementary mesh ends which mesh with one another and define a closed loop when the carrier rails are in the closed over centre position, and the mesh ends of the first and second ring elements being spaced from one another when the carrier rails are in the open over centre position.

7. A ring mechanism as claimed in claim 6, wherein the indentation extends along the longitudinal axis of the cover rail and is arcuate when viewed along the longitudinal axis.

8. A ring mechanism as claimed in claim 7, wherein the indentation is semi-circular in section.

9. A ring mechanism as claimed in claim 6, 7 or 8, wherein the indentation is concave when viewed from above.

10. A ring mechanism as claimed in claim 6, 7 or 8, wherein the indentation has spherical end portions.

11. A ring mechanism as claimed in claim 6, which includes a plurality of pairs of first and second ring elements, wherein the indentation extends along the longitudinal axis between the pairs of ring elements.

12. A ring mechanism as claimed in claim 11, which includes two end pairs of ring elements adjacent either end of the cover rail and at least one other pair of ring elements between the end pairs of ring elements, wherein the indentation extends between the end pairs of ring elements and through the other pairs of ring elements.

13. A ring mechanism as claimed in claim 11 or 12, which includes a pair of openings adjacent to the ends of the indentation in said plain parts.

14. A ring mechanism as claimed in claim 11 or 12, which includes a pair of openings adjacent to the ends of the indentation in said plain parts and mounting means located in the openings on the top section of the cover rail and extending through the carrier rails for mounting the ring mechanism to a loose-leaf binder.

15. A ring mechanism as claimed in claim 6, 7 or 8, wherein the indentation is dimensioned and positioned to contact abutting edges of the carrier rails when in the open over centre position.

16. A cover rail substantially as hereinbefore described with reference to the accompanying drawings.

17. A ring mechanism substantially as hereinbefore described with reference to the accompanying drawings.