Loose-leaf Binder Construction

Abstract

A plastic, i.e., synthetic resin, backbone or spine for a loose-leaf binder with integral studs for securing a ring member and separate abutments for inhibiting movement of the ring member along the backbone. In one embodiment the backbone is insertable as a separate member between plies of a binder cover. In another embodiment it forms an integral portion of a unitary plastic loose-leaf binder cover. The studs are headed, with a slot to allow deformation and insertion into apertures of a ring member. Upon localized heating of the heads, plastic flows into the slots to prevent removal of the ring member.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to loose-leaf binders.

2. Prior Art

Two types of loose-leaf ring binders pertinent to the present invention include the low cost, plastic covered, binders and the more expensive "case made" binders, both of which utilize conventional metal rings that can be opened and snapped closed.

The low cost, plastic covered, binders are typically comprised of a vinyl covering formed from two sheets in overlying relationship, that are divided transversely into two cover leaves and a central spine portion. Reinforcement, usually cardboard, is provided in each cover leaf, between the two vinyl plies, and a metal or cardboard backplate is inserted between the plies in the spine portion, to support a snap-action ring member, which is secured to the backplate with rivets. Metal backplates offer substantially greater strength over cardboard and are typically curved transversely to provide an improved appearance to the spine of the binder.

When a vinyl cover of the above type having a metal backplate is manufactured, the backplate is inserted after the cover is fabricated. To facilitate this, a space or pocket for the metal backplate is preserved with a cardboard insert in the spine portion between the two plies. When the two plies are sealed about the cover leaf reinforcements and between the cover leaves and the spine portion with a heat sealing mechanism, the temporary use of the nonconductive cardboard insert in place of the metal backplate prevents arcing or shorting of the electronic sealing machine used to seal the cover plies. It also avoids any damage to the vinyl that might otherwise be caused by sharp edges of the metal backplate when the vinyl plies in the hinge areas are pressed together for heat sealing. A slit is then made in the spine portion, usually across one end, to permit removal of the cardboard spacer and insertion of the metal backplate. This construction is disadvantageous, especially when it is considered that the binder is intended to be a low cost product, because the metal backplate is relatively expensive and substantial labor and handling are required to both insert and remove the cardboard spacer and subsequently insert the metal backplate having extending rivets that stretch the plastic during insertion. Thereafter, the rivets used to attach the metal ring assembly against the spine portion require hand peening.

So-called "case made" binders, which also use metal backplates, are generally of more expensive construction than vinyl-covered binders of the construction described above. This is primarily due to the utilization of higher quality covering material and custom fitting to provide a better appearance. For example, the cover leaves are typically covered with cloth, leather, simulated leather, plastic, or the like, and include an inside lining or cover, and often utilize separate metal hinges between the spine portion and the cover leaves. These binders have typically been provided with metal backplates that are curved transversely for a more pleasing appearance, and substantial labor has been required in manufacturing these case made binders.

SUMMARY OF THE INVENTION

The present invention relates to loose-leaf binder constructions and specifically to a backbone or spine of thermoplastic synthetic resin for a loose-leaf binder, in the form of either an insert for a fabricated cover or as an integral part of a molded cover.

When in the form of an insert, the backbone of the present invention can embody the advantages of the metal backplate yet it can also be initially located between vinyl plies of the spine portion of a low cost binder during electronic sealing, and thereby eliminate the use of a spacer and the necessity of subsequently removing the spacer and inserting the backplate. Further, the plastic backbone has no tendency to cut through the vinyl plies in use, as does the metal backplate.

It has the further advantage of being more easily and conveniently inserted than a metal backbone when a cardboard insert or spacer is to be replaced. This is advantageous because often the plastic cover plies will be sealed wiht a cardboard backbone spacer as previously described for stock and then a backbone and ring binder subsequently installed as needed. A plastic backbone facilitates insertion because it can be longitudinally bowed without permanent deformation. As a result, installation can be made through a longitudinal slit between apertures in the plastic that received the studs or rivets by bowing the backplate and inserting the ends at opposite ends of the slit and then allowing them to slide under the cover ply to the end of the backbone portion as the backplate returns through its inherent resiliency to the original shape. Unlike the transverse slit required at the end of the backbone portion for insertion of a metal backplate, this slit is completely covered by the ring member after installation.

When the improved backbone construction is used as a part of an entire molded cover, a loose-leaf binder can be provided that in appearance and feel is very similar to a "case made" binder, but which eliminates the need for a metal backplate, covering material, and separate hinges. This results in substantial labor savings.

In both types of construction, the plastic spine insert or integral spine portion includes integral plastic studs, typically two, that are spaced longitudinally along the spine, to be received in apertures and rivet sleeves of a ring member. In a preferred construction, the studs have heads and slots in the end that permit compression of the heads for insertion through the rivet sleeves. The heads then retain the ring member. Heat is applied to deform the head into close retaining relationship with the ring member, and to cause the thermoplastic material to flow into the slot of the head, preventing subsequent compression of the head and thereby inhibiting removal of the ring member.

An important feature of the present construction is the inclusion of one or more integral abutments in addition to the studs, projecting forwardly from a front surface of the spine or backbone that receives the ring member. The integral abutment or abutments engage the ring member and inhibit longitudinal movement of the member relative to the spine. This assures that a load applied to the ring member in a direction longitudinally thereof, as by the weight of sheets carried by the binder when the binder is upright, will not be resisted only by the studs. This, in turn, assures that the studs, which have a limited diameter (and, hence, a limited strength) governed by the standard diameter of the rivet-receiving apertures of a ring member, will not be sheared from the spine during use. The combination of integral studs for attaching the ring member and integral abutments of high shear strength provides a secure and rigid attachment, which assures that even at low temperatures, where the plastic may become more brittle than normal, forces applied to the ring members during shipment or use of assembled binders will not cause the studs to fail.

In the preferred embodiment of a backgone or spine constructed as an insert for a vinyl loose-leaf binder of the type described above, integral abutments are provided closely adjacent a base portion of the studs. In a preferred embodiment, two straight ridges extend transversely of the backbone length on diametrically opposite sides of each stud and lie closely adjacent one end of a rivet sleeve carried in an aperture of the base of the ring member, in which the stud is received. Thus, when the ring member is against the backbone and the studs project through the rivet sleeves and apertures of the ring member, the base of each rivet sleeve will be confined against movement longitudinally of the backbone by the transverse ridges. The ridges can be formed either by a recess in the backbone or spine that receives the base of the rivet sleeve, or by raised walls projecting from the spine, and in no way detract from the appearance of the binder, since they are concealed behind the ring member.

Where the backbone portion forms a part of an integral one-piece cover, a generally straight abutment for inhibiting movement of the ring member is provided, in the preferred embodiment, at each end of the backbone portion. These abutments may be provided either alone or in combination with the ridge abutments of the type described above. The straight abutments extend across the width of the backbone portion adjacent ends of the ring member, and serve to prevent longitudinal movement of the ring member relative to the backbone. In addition, they also enhance the appearance of the molded binder by partially obscuring and enclosing the ends of the ring member.

In the preferred constructions of both embodiments, when a ring member is placed against the front surface of the backbone or backbone portion, with the integral studs extending through the apertures and rivet sleeves of the ring member, the extending ends of the studs are each formed by the application of heat into a head that contacts the ring member and retains the ring member against the backbone. When viewed from the outside, the backbone of the binder has no exposed rivet heads, which detract from the appearance of many conventional binders.

As a result of the present construction, low cost vinyl binders with curved backbones and without exposed rivets are closely competitive in price with binders having flat cardboard backbones and exposed rivets, and are substantially less expensive than vinyl binders with metal backplates. The one-piece plastic binders are significantly less expensive than case made binders.

The above and other features and advantages of this invention will become more apparent from the detailed description that follows, when considered in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a backbone for loose-leaf binder, constructed in accordance with the present invention;

FIG. 2 is a partial sectional view taken along the line 2--2 of FIG. 1;

FIG. 3 is an exploded view, with parts broken away, of a plastic loose-leaf binder incorporating the present invention;

FIG. 4 is a transverse sectional view taken approximately along the line 4--4 of FIG. 3, with parts omitted;

FIG. 5 is a partial sectional view taken along the line 5--5 of FIG. 4;

FIG. 6 is a perspective view of a one-piece loose-leaf binder cover and backbone embodying the present invention; and

FIG. 7 is a partial perspective view of the binder cover shown in FIG. 6, including a ring member secured thereto.

DESCRIPTION OF PREFERRED EMBODIMENTS

With reference to FIG. 1 to 5, a one-piece plastic backbone insert 10 is shown for use in a vinyl binder cover 12, which, along with a conventional metal ring member 14, forms a low cost loose-leaf binder. The backbone 10 serves to rigidify the spine portion of the binder 12 and to secure the ring member 14 to the cover. It is placed between an outer ply 16 and an inner ply 17 of plastic sheets, typically vinyl, that are electronically-sealed together to form the binder cover 12.

The backbone 10 is comprised of a plate portion 20 adapted to extend substantially the entire height of the binder cover 12, i.e., the length of a spine portion 18, as best illustrated in FIG. 3, and is of sufficient width to extend substantially the width of the spine portion, as best illustrated in FIG. 4. The thickness of the plate portion is sufficient to establish suitable rigidity to the spine. In the preferred embodiment, the plate portion 20 is curved transversely, both for the sake of appearance and feel of the binder cover and also to increase the rigidity for a given thickness of the backbone. The backbone, including all integral parts thereof, is constructed of a thermoplastic material of high strength and toughness, which avoids substantial brittleness at low temperatures. For commercial considerations, the material must be of relatively low cost. A satisfactory material is polypropylene. Preferably, the backbone is injection molded.

Two integral studs 22, 23 extend perpendicularly from the concave surface 20a of the plate portion 20 of the backbone, adjacent opposite ends thereof. Each has a stem portion 22a, 23a that is circular in cross-section, an enlarged head portion 22b, 23b at the end, and a longitudinal slot 24, 25 extending the full width and height of the head and partially into the stem portion. Each head includes, as shown in connection with the stud 22 in FIG. 2, a radial shoulder 22c and a tapered end surface 22d. Abutments or ridges 26, 27 and 28, 29 are associated with each stud 22, 23 respectively, and project from the concave surface 20a. Each extends transversely of the backbone on a diametrically opposite side of the associated stud from the other abutment of the pair, spaced from the base of the stud to closely receive the base of a rivet sleeve. Each abutment extends forwardly beyond the adjacent backbone surface a distance substantially less than that of the stud.

The stud stems 22a, 23a are of a diameter that will fit closely within a sleeve 30 carried in an aperture 31 of a metal base 32 of the ring member 14. The stud heads 22b, 23b are of a diameter and the slots 24, 25 of a width that will permit the head to be forced through a passageway that will receive the stem portion, by virtue of the outward taper of the end surface of the head portion and the ability of the plastic material to deform. The stud thereafter returns to its initial shape by virtue of the resilience of the plastic material. The length of the stud stems 22a, 23a is sufficient for the stud heads to project above, i.e., through, the base of the ring member 14 when the member is positioned against the spine of the binder cover, with the shoulder portions 22c and 23c, (FIGS 2 and 5) closely overlying the base of the ring member.

As best shown in FIGS. 4 and 5, the sleeve 30 carried by the ring member has a flange or flared portion 34 at the base, adapted to seat against the spine or backbone of the binder cover. The distance between each upstanding abutment 26, 27 and 28, 29 is established to closely receive the flange 34 and restrict movement of each sleeve in directions essentially longitudinally of the plate portion 20. Typically, a portion of the vinyl cover 17 will overlie the abutments unless a large aperture is provided for the studs to project through. The spacing between adjacent abutments accommodates the vinyl thickness along with the diameter of the sleeve flange, as shown in FIG. 5.

After assembly of the ring member, the slots 24, 25 are filled or blocked by slightly melting the head portions of the studs, to cause melted plastic to flow into the slots. This can be readily accomplished by the application of localized heat, because the backbone is formed of a thermoplastic material. At the same time, it is preferable to slightly shape and compress the head toward the ring member to eliminate any clearance between the head and ring member, which is initially established to facilitate manufacturing tolerances of ring members. The ring member is retained against the spine of the binder cover because the head can no longer be deformed to a compressed condition in which it can pass through the surrounding sleeve.

It will be apparent from the construction of the backbone 10 that, when a ring member 14 is secured to a backbone, a force applied to the ring member in a direction longitudinally of the backbone will be resisted by both he shear strength of the studs and that of the ridges or abutments 26 and 28 or 27 and 29. It will be further appreciated that the abutments 26-29, if of adequate thickness to provide sufficient strength, limit the shear load that can be applied to the studs longitudinally of the backbone and prevent the studs from failing in shear.

The construction and manner of assembly of the completed binder is best understood from FIGS. 3 and 4. The inner vinyl ply 17 of the binder cover, with precut apertures, one of which is shown at 40 in FIGS. 3 and 5, for receiving the studs 22, 23 is laid flat, and cardboard reinforcement sheets 38, 39 are placed on the inner ply in proper position to reinforce cover leaf portions of the binder cover. The backbone insert 10 is placed between the cardboard reinforcement sheets 38, 39 on the inner ply 16, with the studs extending downward through the apertures 40 and into holes of a fixture that positions the backplate. The outer vinyl cover ply 16 is placed over the inner ply, cardboard reinforcement sheets, and backbone. Inner and outer plies are then electronically sealed about the margins and along opposite longitudinal edges of the backbone, the latter serving to form hinge portions 41, 42 between the backbone and the cardboard reinforcement sheets. Because of the complete absence of metal parts comprising the binder cover 12, all danger or risk or arcing or shorting the electronic sealing machine is eliminated. Furthermore, because all edges of the plate portion 20 are relatively dull and smooth, there is no tendency for the edges to cut through either ply 16, 17 during use or during assembly when the two plies are pressed together and sealed along the edges.

The metal ring member is attached to the vinyl binder cover by placing it over the backbone and inner ply 17, with the sleeves 30 aligned axially with the studs 22, 23. The ring member is then forced onto the studs until the stud heads emerge through the sleeves and above the ring member. The extending head of the studs 22, 24 are then locally heated to a temperature at which at least a portion melts and flows into the respective slot to retain the metal ring member in place.

Where a binder cover has been pre-fabricated with a cardboard backbone, a backbone 10 embodying the present invention can be substituted by forming a longitudinal slit from one aperture 40 to the other in the vinyl ply 17, removing the cardboard backbone and inserting the present one by bowing the plate portion 20 upward in the center and tucking the ends beneath the upper vinyl ply at opposite ends of the longitudinal slit and allowing the plate to spring back to its original shape. The ring member is then attached in the manner described above.

As shown in FIGS. 6 and 7, the present invention can be embodied in a molded, one-piece, binder cover 50 of thermoplastic material the same as that used for the backbone insert 10. The binder cover 50 includes integral front and back cover leaves 51, 52, connected to an intermediate backbone portion 53 through parallel integral hinge portions 54, 55 of reduced thickness. The entire cover is preferably injection molded, permitting certain finished detail to be provided, such as the simulation of an embossed or grained covering material and inner liner, and a transverse curvature to the backbone 53, so that the cover has the appearance and feel of a case made binder, but without requiring the hand labor.

Two studs 58, 59 extend upward from an inner concave surface 53a of the backbone portion 53 and two transverse abutments 60, 61 and 62, 63 are located adjacent each stud. The studs 58, 59 and the abutments 60-63 are constructed identically to and function in the same manner as the studs 22, 23 and abutments 26-29 of the backbone insert 10.

Two straight end-abutments 66, 68 are provided, each adjacent an opposite end of the backbone portion 53. These straight end-abutments extend substantially the width of the backbone portion 53 and have a straight top surface 66a, 68a. The depth of the abutments is slightly less than the depth of the curvature provided by the concave configuration of the backbone portion 53. See FIG. 7. The thickness of the abutments 66, 68 is approximately equal to the thickness of the backbone portion, which is sufficient to provide a high degree of rigidity and strength to the end-abutment. With this construction, the end-abutments reinforce or help rigidify the curvature of the backbone portion 53 and prevent longitudinal movement of a ring member 14' along the backbone portion, in either direction. They also provide the additional function of partially obscuring and enclosing the ends of the ring member 14', to enhance the appearance of the binder. While the preferred embodiment utilizes both the abutments 60, 61 and 62, 63 adjacent the studs and the end-abutments 66, 68 for maximum strength, the end-abutments can be used alone. Thus, any shear load applied to the studs 58, 59 through the ring member in a direction substantially along the length of the backbone, is limited either by the abutments 66, 68, alone, or along with the walls 60-63. A severe shear load may be applied, for example, when a large ring binder is stood on its end, especially if it is so placed in a sharp or forceful manner. This can be a particular problem if the binder material is cold and therefore somewhat more brittle than usual, as often occurs during use. For example, a catalog binder carried in a trunk of an automobile during the winter will become cold and more brittle and, if used while still cold, the studs 58, 59 may be more apt to fail in shear than they normally would. With the present construction, the shear load is borne by one of the end-abutments and, if present, also by two of the abutments 60-63 as soon as the studs begin to deform from the load.

While the preferred embodiments of the present invention have been disclosed in detail, it will be appreciated that various modifications or alterations may be made therein, without departing from the spirit and scope of the invention set forth in the appended claims.

Claims

1. A backbone or spine of synthetic resin for supporting and securing a ring element in a loose-leaf binder, said backbone being thin, narrow, and elongated, with a front surface adapted to extend behind a ring element, and including first and second integral means extending forwardly of said front surface for engaging a ring element, said first means serving to secure said element against said front surface and said second means serving to obstruct relative shifting of a secured ring element along the backbone while allowing movement of the element forward and away from the backbone, said second means projecting forwardly of said front surface a

2. A device as set forth in claim 1 wherein said first integral means comprises a stud adapted to extend through an aperture in a ring element.

3. A device as set forth in claim 2 wherein said stud is headed and has a

4. A device as set forth in claim 3 wherein said synthetic resin is thermoplastic and said stud is deformable to a stable shape through

5. A device as set forth in claim 2 wherein said second integral means comprises a ridge extending transversely of the beackbone adjacent each stud, adapted to engage a rivet sleeve carried in an aperture of a ring

6. A plastic, e.g., synthetic resin, backbone for a loose-leaf binder cover, insertable between plies of the cover and adapted to secure a ring element to the cover, said backbone being thin, long and narrow, with smooth, dull, side edges; having a front surface adapted to extend behind a ring element; and including first and second integral means extending forwardly of said front surface for engaging a ring element, said first means serving to secure said element against said front surface and said second means serving to resist relative shifting of a secured ring element along the backbone while allowing movement of the element forward and away from the backbone, said second means projecting forwardly of said front

7. A device as set forth in claim 6 wherein said backbone is transversely curved and sufficiently flexible and resilient longitudinally to permit bowing without permannent deformation, and said first integral means comprises two studs adapted to extend through apertures in a ring element, each stud having an enlarged head at the distal end with a longitudinal slot in the end that extends at least the full length and width of the

8. A device as set forth in claim 7 wherein said second integral means includes a ridge adjacent each stud, extending transversely of the backbone and projecting forwardly of said front surface a distance less than the height of the adjacent stud, adapted to engage a portion of a ring element that is secured to said surface by said studs and inhibit

9. A one-piece synthetic resin binder cover adapted to receive and secure a ring element, and with the ring element to form a loose-leaf binder, said binder cover comprising two cover portions and an intermediate backbone portion, delineations therebetween being defined by thinner hinge-forming portions, said backbone portion being narrow and elongated, with a surface facing inwardly of the cover, against which a ring element is positionable, and having first and second integral means extending forwardly of said surface for engaging a ring element said first means serving to secure said element against said inwardly facing surface and said second means adapted to lie directly adjacent a part of a ring element secured to the backbone and serving to retard relative shifting of a secured ring element along the backbone while allowing movement of the element toward and away from the backbone, said second means projecting from said inwardly facing surface a distance less than that of said first

10. A device as set forth in claim 9 wherein said first integral means comprises a plurality of studs adapted to extend through apertures in a

11. A device as set forth in claim 10 wherein said synthetic resin is thermoplastic, said studs are headed and slotted, and are permanently

12. A device as set forth in claim 10 wherein said second integral means comprise a ridge adapted to engage a rivet sleeve carried in an aperture

13. A device as set forth in claim 12 wherein said second integral means further comprise additional ridges adjacent opposite ends of the backbone

14. A one-piece binder cover of synthetic resin adapted to receive and secure a ring element and with the ring element to form a loose-leaf binder, said binder cover comprising two cover portions and an intermediate backbone portion, delineations therebetween being defined by thinner hinge-forming portions, said backbone portion being narrow and elongated, with a surface facing inwardly of the cover, against which a ring element is positionable, and having first integral means extending forwardly of said surface for engaging and securing a ring element to said backbone portion, and two integral abutments, each at opposite ends of said backbone portion, extending forwardly of said surface and transversely of the longitudinal extent of the backbone, adapted to lie beyond and directly adjacent ends of a ring member attached to the binder

15. In combination, a backbone of a loose-leaf binder and a ring element secured thereto, said backbone being made of synthetic resin, narrow and elongated in shape, with a front surface that extends behind the ring element, a plurality of synthetic resin studs, integral with said backbone and extending forwardly from said front surface, said ring element having apertures and sleeves through which said studs extend, and integral abutment means extending from said front surface a distance less than said studs, directly adjacent said ring member, positioned to inhibit longitudinal movement of the ring member relative to said backbone while permitting movement toward and away therefrom, said studs having integral heads engaged with said ring member to retain said ring member against

16. A combination as set forth in claim 15 wherein said abutment means includes at least two projections, each extending transversely of the backbone, one located adjacent each opposite end of the backbone, beyond

17. A combination as set forth in claim 15 wherein said abutment means includes ridges each having a portion extending transversely of the backbone directly adjacent each sleeve of the ring member through which

18. A combination as set forth in claim 17 wherein said abutment means further includes at least two projections, each extending transversely of the backbone, one located adjacent each opposite end of the backbone,

19. A backbone or spine of synthetic resin for supporting and securing a ring element in a loose-leaf binder, said backbone being thin, narrow, and elongated, with a front surface adapted to extend behind a ring element, and including an integral stud extending forwardly of said front surface adapted to extend through an aperture in a ring element and secure the ring element to the backbone, and an integral ridge extending forwardly of said front surface and transversely of the backbone adjacent each stud, adapted to engage a rivet sleeve carried in an aperture of a secured ring element through which said stud is constructed to extend and thereby

20. A plastic, e.g., synthetic resin, backbone for a loose-leaf binder cover, insertable between plies of the cover and adapted to secure a ring element to the cover, said backbone being thin, long and narrow, transversely curved, with smooth, dull, side edges sufficiently flexible and resilient longitudinally to permit bowing without permanent deformation; having a front surface adapted to extend behind a ring element; and including two integral studs extending forwardly of said front surface and adapted to extend through apertures in a ring element for engaging and securing the ring element to the backbone, each stud having an enlarged head at the distal end with a longitudinal slot in the end that extends at least the full length and width of the head, and a ridge adjacent each stud extending transversely of the backbone and projecting forwardly of said front surface a distance less than the height of the adjacent stud, adapted to engage a portion of a ring element that is secured to said surface by said studs and inhibit relative shifting of

21. In combination, a backbone of a loose-leaf binder and a ring element secured thereto, said backbone being made of synthetic resin, narrow and elongated in shape, with a front surface that extends behind the ring element, a plurality of synthetic resin studs, integral with said backbone and extending forwardly from said front surface, said ring element having apertures and sleeves through which said studs extend, said studs having integral heads engaged with said ring member, retaining said ring member against said front surface, and integral abutment means extending from said front surface, directly adjacent said ring member, positioned to inhibit longitudinal movement of the ring member relative to said backbone, said abutment means including at least two projections, each extending transversely of the backbone, one located adjacent each opposite end of the backbone, beyond the longitudinal extent of the ring member.

22. In combination, a backbone of a loose-leaf binder and a ring element secured thereto, said backbone being made of synthetic resin, narrow and elongated in shape, with a front surface that extends behind the ring element, a plurality of synthetic resin studs, integral with said backbone and extending forwardly from said front surface, said ring element having apertures and sleeves through which said studs extend, said studs having integral heads engaged with said ring member, retaining said ring member against said front surface, and integral abutment means extending from said front surface, directly adjacent said ring member, positioned to inhibit longitudinal movement of the ring member relative to said backbone, said abutment means including ridges each having a portion extending transversely of the backbone directly adjacent each sleeve of

23. A combination as set forth in claim 22 wherein said abutment means further includes at least two projections, each extending transversely of the backbone, one located adjacent each opposite end of the backbone, beyond the longitudinal extent of the ring member.