US3776648A

US3776648A - Looseleaf binder mechanism

Info

Publication number: US3776648A
Application number: US00229831A
Authority: US
Inventors: R Price
Original assignee: Litton Business Systems Inc
Current assignee: TRIUMPH-ADLER AG A CORP OF GERMANY; Western Atlas Inc
Priority date: 1972-02-28
Filing date: 1972-02-28
Publication date: 1973-12-04
Anticipated expiration: 1990-12-04
Also published as: DE2227625B2; IT957637B; CA956197A; DE2227625C3; DE2227625A1; GB1352295A; FR2139289A5; NL7207007A

Abstract

A flexible post looseleaf binder having novel post hold-down slide means adapted to be easily inserted into and, if desired, removed from its retaining channel. To insert the slide means into the channel, the slide is held in a first angular position relative to the channel. In this position, the body of the slide presents to the channel top opening a maximum width not greater than substantially equal to the width of the channel opening, so that the slide can readily be inserted into the channel. After insertion, the slide is rotated to a second angular position. In this latter position, an abutment portion of the slide underlies a lateral wall portion of the channel, so that the slide is locked against accidental removal from the channel. In a modified form, each slide is provided with a hook-like hanger extension. When the slides are moved to the outward ends of the channel, these extensions protrude outwardly beyond the binder covers, and are used to hang the binder in a file cabinet or the like. Detent structure provided on each slide holds the slide releasably latched in the foregoing end position.

Description

United States Patent 1 Price LOOSELEAF BINDER MECHANISM Primary ExaminerWm. H. Grieb Attorney-Norman Friedman et a1.

[57] ABSTRACT A flexible post looseleaf binder having novel post hold-down slide means adapted to be easily inserted into and, if desired, removed from its retaining channel. To insert the slide means into the channel, the slide is held in a first angular position relative to the channel. In this position, the body of the slide presents to the channel top opening a maximum width not greater than substantially equal to the width of the channel opening, so that the slide can readily be inserted into the channel. After insertion, the slide is rotated to a second angular position. In this latter position, an abutment portion of the slide underlies a lateral wall portion of the channel, so that the slide is locked against accidental removal from the channel.

In a modified form, each slide is provided with a hook-like hanger extension. When the slides are moved to the outward ends of the channel, these extensions protrude outwardly beyond the binder covers, and are used to hang the binder in a file cabinet or the like. Detent structure provided on each slide holds the slide releasably latched in the foregoing end position.

18 Claims, 18 Drawing Figures PAIENI nm 4191s snzinur a FIG.l

PAIENIEDHEE 4W 3.776.848

SHEET 20F 3 Q FG.1O 5? FIG.11

LOOSELEAF BINDER MECHANISM BACKGROUND OF THE INVENTION Flexible post looseleaf binders conventionally include mechanism for holding the flexible posts in bentover position when the binder is in assembled condition. Such mechanisms are sometimes known as compression mechanism. They customarily include a slide movable in a channel or the equivalent to and from a position overlying and thereby holding down the bentover flexible post.

In one prior art form, the slide is of a somewhat larger width than the longitudinal channel opening and the slide is resiliently pressed or snapped downwardly into the channel to be slidably retained therein. However, in this kind of device a considerable force is usually required to insert the slide into the channel. Furthermore, the slide cannot readily be removed from the channel.

In another form of prior art device the width of the channel opening, i.e., between its usual top flanges, is greater along a short portion of its length, to thereby make it easier to insert the 'slide edge of the channel through this enlarged width portion. However, in this version there is the danger that the slide will inadvertently be removed from or fall outof the channel at the greater width channel opening.

SUMMARY OF THE INVENTION In accordance with the present invention, there is provided a unique compression slide and a unique cooperation between the slide and the channel or the like in which it is to be slidably retained. To insert the slide into the channel, the slide is first held in a first angular position. In this angular position, the body portion of the slide presents to the top opening of the channel a maximum width not greater than substantially the same width, and preferably a slightly smaller width, than the width of the channel opening. Thus, the slide can now be readily inserted into the channel. After insertion, the slide is rotated to a second angular position. This latter rotation of the slide member causes an abutment portion of the slide member to be moved to effective position to underlie a lateral wall portion of the channel, said lateral wall portion cooperating with the slides abutment portion to effectively block the slide against its unintended removal from the channel.

If it is desired to remove the slide from the channel, the foregoing process can be reversed. That is to say, the inserted slide is rotated from its second angular position back to the first angular position, whereupon the slide can readily be withdrawn from the channel.

It is a primary object of the present invention to provide a novel compression means for a flexible post looseleaf binder. 1 It is a further object to provide a compression slide which is easily insertedinto its retaining track or channel.

sertion is rotated to another angular position to retain the slide in the track or channel.

It is a further object to provide a compression slide which is easily removable from the retaining track or channel by reversal of the foregoing insertion steps.

It is a further object to provide a compression slide having a hook-like hanger extension by which the binder can be supported in a file cabinet or the like.

It is a further object to provide means for releasably latching the slide in the position wherein the foregoing hanger extension of the slide protrudes to effective position beyond the binder covers.

The above and other objects, advantages and features of the invention will become apparent to those of ordinary skill in the relevant art from the following detailed description of preferred embodiments of the invention when read in conjunction with the accompanying drawings in which:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a top plan view of a looseleaf binder incorporating the novel compression slide of the present invention.

FIG. 2 is an enlarged fragmentary view taken on line 11 II of no. 1.

FIG. 2A is an enlarged portion of FIG. 2.

FIG. 3 is an enlarged fragmentary view taken on line III III of FIG. 1.

FIG. 4 is an enlarged fragmentary top plan view showing the slide in its first angular position for insertion of the slide into the channel.

FIG. 5 is a view similar to FIG. 4 but showing the slide after it has been inserted into the channel and rotated to its second angular position in assembled relation with the channel.

FIG. 6 is a bottom plan view of the slide.

FIG. 7 is a front elevation view of the slide.

FIG. 8 is a fragmentary enlarged top plan view showing one of the end caps mounted in the channel.

FIG. 9 is a sectional view taken on line IX IX of FIG. 8.

FIG. 10 is a sectional view taken on line X X of FIG. 8.

FIG. 11 is a top plan view of the end cap.

FIG..11A is an end elevational view showing the end cap mounted in the channel.

FIGS. 12 16 relate to a modified form of the compression slide, in which the slide is provided with a being respectively provided for the opposite ends of the binder.

FIG. 14 is a perspective view showing the binder supported in hanging fashion by the modified slides of FIGS. 12 and 13.

FIG. 15 is an enlarged fragmentary top plan view taken on line XV XV of FIG. 14.

3 FIG. 16 is a front elevational view'of the slide of FIG.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring particularly to FIGS. 1 3 of the drawings, the

reference numerals

2 and 4 designate conventional binder covers of one typical form. Mounted in the binder on conventional binder posts 6 are a number of looseleaf sheets 8. The sheets 8 as shown herein are computer print-out tab sheets. However, it will be understood that the principles of the invention are applicable to diverse forms of looseleaf binders, and for containing any desired kind of looseleaf sheet.

The binder posts 6 are typically made of nylon and comprise an enlarged diameter head 10 and elongated flexible body portion 12. The body and head portions are joined together by a short substantially cylindrical portion 14 of larger diameter than the body portion, and an intermediate tapered portion 16.

Reference numeral 18 designates elongated upper and lower channel members generally of the type used with this kind of binder. Each of the channel members, which are usually made of metal, comprises a base portion 20, and upwardly and outwardly extending side wall portions 22 which terminate in inwardly extending turned-over flange portions 24.

The bases of channels 18, as well as the

underlying portions

26, 28 of the binder covers 2 and 4 are provided with corresponding rows of longitudinally arranged

holes

30, 32, and 34 respectively. If desired, each channel member 18 may be permanently secured to its related cover member, as by rivets 36.

In use, each binder post is passed through one of the holes in one of the cover members, e.g., 2, and its associated channel member 18, then through the holes 38 in the looseleaf sheets 8, then through the corresponding aligned holes in the other cover member 4 and its associated channel member. The flexible body portion 12 of each binder post is then bent downwardly to lie along the adjacent channel member base portion 20, and it is held in this position by an associated compression slide 40. The novel slides 40 of the present invention will be described shortly.

The short enlarged diameter portions 14 of the binder posts 6 are preferably in a press fit relationship with the holes in channel member base portion 20 so as to prevent the posts from inadvertently working loose. The tapered post portion 16 just inwardly of portion 14 merely serves as a lead-in to enable the posts to be fully inserted through the channel holes 30 without undue difficulty.

The binder posts 6 can be inserted either from above or below, the upper and lower channel members 18 being identical. As shown in FIGS. 1 4 3, the posts have been inserted from below and the compression slides are therefore provided on the upper channel. However, it will be understood that if the posts are inserted from above, then the slides 40 will be provided on the lower channel.

The novel slide 40 of the present invention will now be described. The slide is so constructed that when it blocked relation with and underlying the flanges 24 of the channel. As a result, the slide is held against inadvertent removal from the channel. When it is desired to remove the slide from the channel, the foregoing process is reversed.

The special configuration of the slide which provides for the foregoing functions is best seen in FIGS. 4 7.

The slide includes a head portion 42 and an underlying body portion 44. In use, the underside of the head portion is outside of and may rest on the top of the channel, i.e., on flanges 24. The head portion 42 may, as shown, be substantially square or rectangular in shape, although this particular shape is not critical.

As best seen in FIG. 6, in the present preferred embodiment, the underlying body portion 44 is essentially lozenge-shaped with its longitudinal axis extending generally diagonally of head 42, i.e., between lower left and upper right.

This imaginary longitudinal axis is designated 46 in FIG. 6. Another imaginary axis, at an oblique angle of about 40 to axis 46 and extending parallel to the upper and lower edges of head 42, is designated 48 in FIG. 6.

Referring also to FIG. 2, slide body portion 44 includes a downwardly opening central recess 49 open at its ends and defined at its top by two flat

coplanar surfaces

50 and 52. The latter surfaces lie on opposite sides of an elongated upwardly concave arcuate groove 54 open at its opposite ends. Groove 54 runs generally parallel to axis 48. (At this juncture it should be noted that FIG. 6 is a bottom plan view of the slide. Therefore, references in this written description to upwar and the like will, as applied to FIG. 6, have to be considered downward relative to the plane of that figure, and vice versa.) The sides of the aforementioned recesses are defined by flat

vertical side walls

56 and 58; and 62 and 64, of respective depending bar-

like members

68 and 70 extending generally parallel to axis 48.

Each of the

bars

68, 70 includes a lowermost substantially flat horizontal

lower surface

72, 74. Sloping upwardly and outwardly from the latter and formingthe lateral outside side surfaces of

bars

68 and 70 are beveled side surfaces 76, 78. The latters, bevel or slope angle substantially conforms to the angle of outward slope of the channel side walls 22 relative to the channel base 20, since these sloping surfaces of the slide are intended to ride along these sloping side walls, as seen in FIG. 2.

As best seen in FIGS. 2 and 2A and also shown in FIGS. 4 7, the bevel side surfaces 76, 78 are each provided with a very shallow horizontally extending step or

shoulder

80, 82. The angle of slope of the bevel surfaces 76 and 78above and below

respective steps

80, 82 are the same, i.e., are both the slope angle described before, which is the same as the slope angle of the channel side walls 22.

Steps

80 and 82 are of a thickness in the order of 0.012 inches, but are shown exaggerated in FIG. 2 for ease of illustration.

Bar 68 terminates at its right hand end (FIG. 6) in a vertical wall or flat 84 which is substantially parallel to axis 46. Bar 70 similarly terminates at left-hand end in a like vertical flat 86.

Flats

84 and 86 extend up to and are integral with the underside of the slide head 42.

The upwardly and outwardly sloping bevel side surfaces 76, 78 each terminates at its upper end at a horizontal inwardly extending

narrow ledge

88,90 which, together with a short

vertical wall

92, 94 and the over lying, overhanging portion of head 42, forms a reentrant laterally outwardly opening longitudinally extending

slot

96, 98. As seen in FIGS. 2 and 2A, the inwardly turned flanges 24 of channels 18 are adapted to be received in the respective slots 96'and 98 formed along the opposite sides of the slide 40.

Slots

96 and 98 are each open at their opposite ends, slot 96 extending through flat 84 and slot 98 extending-through flat 86.

It is important to note that the distance or width dimension between the parallel

vertical flats

84 and 86 of

bars

68, 70, relative to the axis 46 of slide 40 is substantially equal to and preferably slightly less than the width of the channel opening defined between the inner ends ofthe channel flanges 24. It should further be noted that this width dimension of the body portion 44 of the slide is also the widest dimension of the slide, again relative to axis 46.

The technique for assembling the slides 40 to the channel 18 is as follows. The slide is first angularly oriented relative to the channel so that axis 46 of the slide body portion 44 is substantially parallel to the longitudinal dimension of the channel, as shown in FIG. 4. In this first angular position of the slide, the parallel

vertical flats

84 and 86 of the slide bars 68, 70 will be parallel to the topmost inner side edges of the channel flanges 24; and, as pointed out above, the dimension across these

flats

84 and 86 is the maximum width of the slide in this angular position and this width is slightly less than the width of the channel opening. Accordingly, the slide may now be freely inserted into the channel as limited by either the lowermost

horizontal surfaces

72 and 74 of the slide bars 68, 70 engaging the base of the channel, or by the underside of the slide head 42 engaging the upper edges of the channel flange 24 whichever occurs first depending upon the relative dimensions of the parts. At this point there is of course nothing preventing the slide from inadvertently falling out of the channel or being pulled out of the channel.

The slide is then rotated from the foregoing position of FIG. 2 clockwise to its second angular position, of FIG. 5. Axis 48 of the slide is now parallel to the longitudinal dimension of the channel 18. In the course of this movement, the two

opposed slots

96 and 98 beneath head 42 provide a space or clearance for receiving the inwardly extending flanges 24 of the channel. Also, as the slide is being rotated from the FIG. 4 to the FIG. 5 position, the lowermost end comers of the slide, i.e., at the intersection of flat 84 with sloping bevel surface 76, and at the intersection of flat 86 with bevel surface 86, may engage or hit the respective side walls 22 of the channel, depending on the relative dimensions of the parts. If this occurs, the slide can readily be manually snapped past this interference point, this being permitted by the resiliency of the slide material and/or of the channel. In fact, such a slight amount of interference in rotating the slide to the FIG. 5 position is desirable. It prevents the slide from being inadvertently rotated from the fully assembled FIG. 5 position to the removable position of FIG. 4. In this regard, it will of course be understood that when it is desired to remove the slide from the channel, the slide is merely counterrotated counterclockwise from the FIG. 5 to the FIG. 4 position, whereupon it may be freely removed from the channel. i

The final assembled relationship between the slide 40 and the channel 18 is best seen in FIGS. 2, 2A and 5. The inwardly extending flanges 24 of the channel are disposed within the

slide slots

96 and 98. The slide cannot be inadvertently removed from the channel. The

ledges

88 and 90 forming the bottom sides of the

slots

96 and 98 underlie the inwardly extending flanges 24. These ledges therefore act as abutments or stops to prevent inadvertent removal of the slide from the channel. The upwardly and outwardly sloping bevel side surfaces 76, 78 of the slide are generally parallel'to the re spective opposed outwardly sloping side walls 22 of the channel and ride therealong.

The slides are of course freely slidable along the length of the channel. It will be recalled that the side bevel surfaces 76 and 78 of the slide are each provided with a shallow step or

ledge

80, 82, below which these bevel surfaces extend slightly outwardly relative to the planes of the upper portions of these bevel surfaces. These slightly protruding lower portions, since they provide a closer fit with the channel side walls, are helpful in stabilizing the slide to minimize any tendency of the slide to wobble loosely in the channel.

The downwardly opening recess 49 of the slide between

bars

68 and 70 provides an opening through which the cooperable binder post body 12 is adapted to extend and thereby be held bent over by the undersurface of the slide. The arcuate groove 54in the slide undersurface provides a mating channel for receiving the post. Because of the latters inherent resiliency, it will tend to be self-biassed upwardly to lie in groove 54.

Each channel 18 is of uniform cross-section from end to end, as distinguished from prior art devices in which the channels are bent inwardly at their opposite ends to form end stops for the slides. For the two purposes of both providing such end stops in the channel, and also shielding the rather sharp end edges of the channel so that a user will not injure himself, there are provided channel end caps 100, as seen in FIGS. 1 and 8 11A. (It will be understood that the slides 40 can if desired of course be used with such conventional channels having their ends bent in to form end stops.)

Each end cap 100 comprises a body portion 102 contoured to fit snugly within the channel, and a head 104 which is adapted to abut the outer end edges of the channel and is of sufficient length and width to completely shield those edges. Head 104 is provided with smoothly rounded edges to avoid cutting the user.

The end cap body portion 102 comprises a central member 106 having an uppermost surface 108 which slopes downwardly from the top edge of head 104. At its opposite sides, the body portion 102 include upwardly sloping wings or

flanges

110, 112. Their slope angle is substantially the same as the slope angle of the channel sidewalls 22 relative to the channel base 20. Grooves or

slots

114 and 116 separate the lastmentioned wings or

flanges

110, 112 from the central portion 106 of the body portion.

On its underside, the end cap is provided with a blind slot 118 extending inwardly from and through the head 104 and into the body portion 106. To firmly secure or latch the cap to the channel, th base 20 of the latter is provided adjacent each of its ends with an upstruck sloping tongue 120. When the body portion 102 of the end cap is inserted into the open end of channel 18, the inner end of the cap body portion presses the inherently resilient upstruck tongue 120 downwardly into the hole in the channel base 20 from which the tongue 1 was struck. The tongue is so held down by the cap until the cap is fully inserted into the channel. At this point, the inherent resiliency of the tongue will cause the latter to snap upwardly into slot 118 formed in the underside of the cap (see FIG. 9). In this final assembled position of the end cap in the channel, the outside faces of the

end cap wings

110, 112 firmly grip the inside of the channel walls 22. Also, the turned-over channel flanges 24 extend over and grip the upper edges of the

end cap wings

110, 112, and also extend downwardly into the grooves or spaces 114,116 provided in the end cap between the aforesaid wings and the central major body portion of the end cap.

The end cap is thereby snugly and substantially permanently mounted in the channel. Any force tending to remove the cap outwardly back through the open end of the channel will be strongly resisted by the upstruck tongue 120 of the channel base bearing against the inner end wall of blind slot 118.

The aforedescribed novel end caps are not limited in their application to use with the novel slides described herein, but can be used with any type of compression slide.

Both the slides 40 and the end caps 100 may be formed in any suitable way of any suitable material. Preferably, they are each molded as a singl integral unit of any suitable synthetic resin material, such as a resilient nylon.

FIGS. 12 16 show a modified form of the slide. Here, the slide 40 is provided with a hook or hanger extension 122, which will protrude outwardly beyond the binder covers 2, 4 when the slides are pushed to the ends of the channel (FIGS. 14, 15). As shown in FIG. 14, the hook extensions can thus be used to support the binder in hanging fashion on the hanger bars 124, 126 of a file cabinet or the like.

, The slide body portion 44 of the FIGS. 12 16 form is constructed and operates exactly the same as the first 3 described form of FIGS. 1 7, and therefore that description need not be repeated here. The head portion 42 of the FIGS. 12 16 modification is like the head 42 of the FIGS. 1 7 form, except that it is provided with the integral longitudinal extension 122 having a slot or cutout 128 to thereby define a hanger hook adjacent to its outer end. The integral hook extension 12 is of the same thickness as the head 42 from which it extends. It will be understood that, as shown in FIGS. 12 and 13 respectively, the slides with the hook extensions 122 will be provided in two respective mirror image versions, i.e., with the hook extensions extending in opposite directions, each of the two versions respectively being provided for the opposite hanger ends of a given channel 18.

To hold the slides securely detented or latched in their end, hook-protruding positions of FIGS. 14 15, the following structure is provided. Integral with the underside of each hook extension 122 is a detent protuberance 130 including an innermost vertical wall 132 terminating at its top in a short horizontal wall 134. The detent protuberance includes a laterally rounded downwardly sloping member whose outer sloping surface provides a cam surface 136.

As the slide is being pushed towards its end, hookprotruding position, the cam surface 136 of the detent protuberance 130 will engage the upper edge of the head 104 of end cap 100 and thereby be cammed upwardly to allow further endwise movement of the slide in channel 18. Ultimately, asthe slide is further pushed in an endwise direction in the channel, when the inner vertical wall 132 of the detent protuberance 130 moves into alignment with the outer end face of the end cap head, the protuberance and the hook extension integral therewith will resiliently snap downwardly into the detented position shown in FIG. 15. It will be understood that the inherent resiliency of the material of which the slide is made will permit the foredescribed upward flexing of the slide and particularly of the hook extension portion thereof. When it is desired to push the slide back inwardly in the channel, the hook extension is merely manually flexed laterally outwardly in a direction away from the channel, to free the protuberance 130 from its latched relation with the head of the end cap.

Like the slide of FIGS. 1 7 the slide of FIGS. 12 16 is preferably made as an integral unit of a suitable material such as a resilient nylon.

The end caps are the subject of another pending US. patent application assigned to the same assignee as the present application, and filed in the name of Billy J. Doolittle, Ser. No. 230,005, filed Feb. 28, 1972.

While there are. shown and described herein certain preferred embodiments of the invention, it will be understood that in practice, the invention and its various features can be practiced in numerous diverse forms. Accordingly, it is intended that the foregoing disclosure be illustrative only and not in any way limitative of the following claims.

I claim:

1. In a looseleaf binder including spaced wall means defining therebetween a longitudinally extending space and a top opening thereinto, said wall means including laterally extending wall portion means:

a slide member adapted to be slidably disposed in said space for sliding longitudinal movement therealong relative to said spaced wall means;

said slide member including a body portion which in a first angular position of said slide member relative to said opening presents to said opening a maximum width not greater than substantially equal to the width of said opening to thereby permit said body portion to be inserted through said opening into the space defined between said spaced wall means;

said slide member after insertion thereof into said space being rotatable relative to said opening to a second angular position;

said body portion of said slide member including abutment means rendered effective by said rota tion of said slide member to said second angular position to underlie said laterally extending wall portion means, said wall portion means cooperating with said abutment means, when said slide is in said second angular position, to block said slide means against removal from said space.

2. The combination according to claim 1, wherein:

said slide member includes a head portion disposed above saidbody portion, said head portion being disposed outside said space when said body portion is disposed within said space.

said head portion providing a manually graspable operating means for manipulating said slide member.

3. The combination according to claim 2:

said head portion being of a width greater than said top opening into said space.

4. The combination according to claim 3:

said laterally extending wall portion means being provided at the top of said space and comprising opposed, spaced, laterally inwardly extending flanges, said top opening into said space being defined between the inner edges of said opposed flanges.

5. The combination according to claim 4:

said slide member being provided with opposed, spaced, longitudinally extending slots adjacent and underlying said head portion;

said slots opening laterally outwardly;

said abutment means comprising a wall of each of said slots.

6. The combination according to claim 5:

said flanges extending into said slots when said inserted slide member is in its second angular position.

7. The combination according to claim 1, including:

means for blocking movement of said inserted slide member from said second to said first angular position.

8. The combination according to claim 1, wherein:

said inserted slide member is rotatable from said sec- 0nd angular position to said first angular position to allow removal of said slide means from said space.

9. The combination according to claim 8, wherein said slide member includes:

overridable means for blocking movement of said slide member from said second to said first angular position.

10. The combination according to claim 5, wherein said slide member further includes:

opposed, spaced bar members depending below said slots and defining between said bar members a recess through which a post of said binder is adapted to extend and be held down by said slide member.

11. The combination according to claim 10, wherein:

each of said bar members includes a vertical, substantially flat surface at an end thereof, the said surfaces of said two bar members being spaced and substantially parallel and defining thereacross said maximum width of said slide member body portion.

12. The combination according to claim 1, wherein:

said slide member includes a substantially hookshaped extension fast therewith and arranged to protrude outwardly beyond the side of said binder when said slide member is slid to a given position adjacent the end of said longitudinally extending space.

13. The combination according to claim 12, further including:

positive latching means for latching said slide member in said given position.

14. The combination according to claim 13, wherein:

said latching means comprises a detent member provided on said slide member.

15. The combination according to claim 14, wherein:

said detent member is provided on said extension of said slide member.

16. The combination according to claim 15, wherein:

said detent member includes a positive latching shoulder.

17. The combination according to claim 1, wherein:

said slide member is provided on its underside with a downwardly opening recess arranged to receive therein the bent-over portion of a binding post.

18. The combination according to claim 17, wherein:

said recess is open at opposed ends thereof.

Claims

1. In a looseleaf binder including spaced wall means defining therebetween a longitudinally extending space and a top opening thereinto, said wall means including laterally extending wall portion means: a slide member adapted to be slidably disposed in said space for sliding longitudinal movement therealong relative to said spaced wall means; said slide member including a body portion which in a first angular position of said slide member relative to said opening presents to said opening a maximum width not greater than substantially equal to the width of said opening to thereby permit said body portion to be inserted through said opening into the space defined between said spaced wall means; said slide member after insertion thereof into said space being rotatable relative to said opening to a second angular position; said body portion of said slide member including abutment means rendered effective by said rotation of said slide member to said second angular position to underlie said laterally extending wall portion means, said wall portion means cooperating with said abutment means, when said slide is in said second angular position, to block said slide means against removal from said space.

2. The combination according to claim 1, wherein: said slide member includes a head portion disposed above said body portion, said head portion being disposed outside said space when said body portion is disposed within said space. said head portion providing a manually graspable operating means for manipulating said slide member.

3. The combination according to claim 2: said head portion being of a width greater than said top opening into said space.

4. The combination according to claim 3: said laterally extending wall portion means being provided at the top of said space and comprising opposed, spaced, laterally inwardly extending flanges, said top opening into said space being defined between the inner edges of said opposed flanges.

5. The combination according to claim 4: said slide member being provided with opposed, spaced, longitudinally extending slots adjacent and underlying said head portion; said slots opening laterally outwardly; said abutment means comprising a wall of each of said slots.

6. The combination according to claim 5: said flanges extending into said slots when said inserted slide member is in its second angular position.

7. The combination according to claim 1, including: means for blocking movement of said inserted slide member from said second to said first angular position.

8. The combination according to claim 1, wherein: said inserted slide member is rotatable from said second angular position to said first angular position to allow removal of said slide means from said space.

9. The combination according to claim 8, wherein said slide member includes: overridable means for blocking movement of said slide member from said second to said first angular position.

10. The combination according to claim 5, wherein said slide member further includes: opposed, spaced bar members depending below said slots and defining between said bar members a recess through which a post of said binder is adapted to extend and be held down by said slide member.

11. The combination according to claim 10, wherein: each of said bar members includes a vertical, substantially flat surface at an end thereof, the said surfaces of said two bar members being spaced and substantially parallel and defining thereacross said maximum width of said slide member body portion.

12. The combination according to claim 1, wherein: said slide member includes a substantially hook-shaped extension fast therewith and arranged to protrude outwardly beyond the side of said binder when said slide member is slid to a given position adjacent the end of said longitudinally extending space.

13. The combination according to claim 12, further including: positive latching means for latching said slide member in said given position.

14. The combination according to claim 13, wherein: said latching means comprises a detent member provided on said slide member.

15. The combination according to claim 14, wherein: said detent member is provided on said extension of said slide member.

16. The combination according to claim 15, wherein: said detent member includes a positive latching shoulder.

17. The combination according to claim 1, wherein: said slide member is provided on its underside with a downwardly opening recess arranged to receive therein the bent-over portion of a binding post.

18. The combination according to claim 17, wherein: said recess is open at opposed ends thereof.