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(11) | EP 0 928 700 A2 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Compressor bar for document file |
| (57) A compressor bar is described for document files having a pair of spaced-apart prongs
which engage holes in sheets of paper to hold them in place in the file; the compressor
bar comprises a base (17) having a pair of spaced-apart openings (18) though which
the prongs can extend; a pair of resilient rods (20) held within the base and extending
between the pair of openings; an arm (22) pivotally attached to the base and comprising
means (34) for flexing the rods at a position between the two openings, the arm being
moveable between a first position in which the flexing means (34) flexes the rods
(20) and a second position in which the rods (20) are not flexed or are flexed to
a lesser extent; and two sets of lands (32), each set being attached to the base between
the flexing means (34) and the respective openings (18), said lands being positioned
to provide a fulcrum about which each rod can pitch whereby the flexing of the rods
(20) by the flexing means (34) causes the spacing between the rods in the openings
(18) to alter between a first spacing in which the rods can grip prongs extending
through the openings and a second spacing that is wider than the first spacing. The
arm (22) is connected to the base (17) by a T-shaped connection member (46) secured
to the arm (22) and having a cross-piece (60) that engages the rods (20) on the side
of the rods remote from the arm (22) at least when the arm is in the second position
to prevent the arm being separated from the base in the said second position, and
a shaft (64) connecting the cross piece to the rest of the arm (22). |
Field of Invention
[0001] The present invention relates to compressor bars for use securing documents within document files of the type that include a pair of prongs that engage holes in the margin of documents to keep the documents within the file. Such prongs may be incorporated into rings or arches for easier reading of the document within the file (so-called ring binders or arch lever files). In order to prevent documents riding up the prongs, compressor bars are placed above the documents in the file, pressed down on the documents and fastened to the prongs.
Prior art
[0002] Compressor bars are known that comprise:
a base having a pair of spaced-apart openings though which the prongs can extend;
a pair of resilient rods held within the base and extending between the pair of openings;
an arm pivotally attached to the base and comprising means for flexing the rods at a position between the two openings, the arm being moveable between a first position in which the flexing means flexes the rods and a second position in which the rods are not flexed or are flexed to a lesser extent; and
two sets of lands, each set being attached to the base between the flexing means and the respective openings, said lands being positioned to provide a fulcrum about which each rod can pitch whereby the flexing of the rods by the flexing means causes the spacing between the rods in the openings to alter between a first spacing in which the rods can grip prongs extending through the openings and a second spacing that is wider than the first spacing.
[0003] The arm is secured to the base by two side-by-side lugs that are inserted into a slot in the base such that the lugs are positioned adjacent to the edge of the slot. The lugs each have a finger that is bent to overlap the edge of the base next to the slot and thereby prevent the arm from being pulled out from the base. Such an arrangement also provides a pivot about which the arm can move between the first and second arm positions. The disadvantage of such an arrangement is that the fingers of the lugs can easily be bent in which case the arm becomes detached from the base. Also, the bending of the fingers is awkward because they are relatively small and inaccessible.
Description of the Invention
[0004] According to the present invention, there is provided a document compressor bar of the above type in which the connection means between the arm and the base comprises a connection member secured to the arm and having:
a cross-piece that engages the rods on the side of the rods remote from the arm at least when the arm is in the second position to prevent the arm being separated from the base in the said second position, and
a shaft connecting the cross piece to the rest of the arm.
[0005] As used herein, the expression "secured to" when applied to two parts includes both the situation in which the two parts are integral and the situation in which the parts were made separately and subsequently joined together.
[0006] Thus, according to the present invention, the arm is secured to the base by the cross piece engaging underneath the rods and preventing the arm being lifted away from the base when the arm is in the second position. When the arm is in the first position (in which it flexes the rod), it is not generally necessary for the cross piece to be engaged under the rods since the tension from the flexing of the rods will retain the arm in place.
[0007] It is preferred that the connecting means also comprises at least one notched lug, the notch of which engages in a slot in the base to provide further resistance to the removal of the arm from the base. The said at least one notched lug preferably extends through the same slot as the member of the connecting means, the arrangement being such that the said connection member engages one extremity of the slot and the notched lugs engage the other extremity, thereby preventing the arm from becoming detached from the base.
Detailed Description of the Drawings
[0008]
Figure 1 is a perspective view from above of the lever arch mechanism of a lever arch file and including a compressor bar of the present invention;
Figure 2 shows the same arrangement as Figure 1 but shows the compressor bar of the present invention compressing documents in the file;
Figure 3 is a perspective view from above of the compressor bar of the present invention in a position such that it can move on the prongs of a lever arch file;
Figure 4 shows the same bar as Figure 3 but in an arrangement that grips the lever arch mechanism such that it cannot move on the prongs of the lever arch file;
Figure 5 is a view of the underside of the compressor bar shown in Figure 3;
Figure 6 is a view of the underside of the compressor bar shown in Figure 4;
Figure 7 is a view of the components of the compressor bar of Figures 3 to 6;
Figures 8 and 9 are perspective views of the top side and the underside (respectively) of the arm of the compressor bar of Figures 3 to 7.
Detailed Description of the Drawings
[0009] Referring initially to Figure 1, there is shown the lever arch mechanism of a document file having prongs 10 that form a closed loop with arched sections 12. The arched sections can be separated from the prongs 10 by movement of lever 14 to allow documents to be removed from the prongs and/or new document to be inserted on the prongs.
[0010] Figure 1 also shows the compressor bar 16 of the present invention. The compressor bar includes a base 17 having two openings 18 through which the prongs of the file pass. Also visible in Figure 1 are rods 20 extending most of the length of the base 17 (as will be described in further detail below) and in particular are located on either side of each of openings 18. An arm 22 is also provided that moves the rods 20 between a position in which they clamp the prongs 10 between them and a second position (shown in Figure 1) in which they do not clamp the prongs and therefore the bar 16 is freely movable on the prongs.
[0011] Referring now to Figure 2, there is shown the arrangement when documents 24 are installed within the file. The margins of the documents have two holes punched in them and they are held in the file by the prongs 10. In order to prevent the documents from moving up and down the prongs, the compressor bar 16 grips the prong and so compresses the documents within the file. The mechanism of the compressor bar will be described in further detail below.
[0012] Referring now to Figures 3 to 9 and initially to Figures 3 and 5, there is shown the compressor bar having a base 17, which will generally made of pressed steel. The base has a flat bottom rim 26 that engages the document (see Figure 2). Within the base are a pair of spaced-apart rods 20 (see Figure 5 in particular) that extend between and across the openings 18. The rods are held centrally by two collars 28 and the ends of the rods are supported on ledges 30. Two sets of lands 32 are provided adjacent to the openings 18 that engage respectively the sides of the rods 20. The collars 28, the ledges 30 and the lands 32 can all be pressed out from the same sheet material as is used to form the base 17.
[0013] Arm 22 is pivotally connected to the top surface of the base 17. The arm is in the form of a rocker having a pair of downwardly facing cams 34 (see in particular Figures 8 and 9). The cams extend through a central opening 36 in the base 17 and their function is to push the centres of the rods outwardly away from each other as will be described in further detail below.
[0014] The base also has an additional U-shaped slot 38 (see Figure 7); the arm 22 has a pair of sidewardly spaced-apart lugs 40 that each has a finger 42 providing a notch 44 (see Figure 9). The arm also has a T-shaped member 46 located between the lugs 40. The lugs 40 are placed in the side sections 48 of the U-shaped slot 38 while the T-shaped member 46 passes through the base section 50 of the slot 38. The notches 44 engage the end walls 52 of the slot 38. By bending the T-shaped member 46 so that it presses against wall 53 at the base of the slot 38, the notches 34 can be kept in engagement with the end walls 52 and thus provide a pivot for the rocker arm 22 and also prevent the rocker arm 22 from becoming detached from the base 17.
[0015] As shown in Figure 5, the two rods 20 are parallel to each other, and, in the openings 18, the spacing is greater than the diameter of the prongs 10 of the document file. Thus, the compression bar can easily be moved up and down the prongs and removed altogether from the prongs. In this condition, the rods 20 are unstressed and this occurs when the lever arm 22 is in the position showed in Figure 3 with the end 54 of the arm 22 being raised and the end 56 being depressed and lying against the top surface of the base 17.
[0016] When the end 54 of the arm 32 is pressed down, this causes the arm to pivot about the notches 44, thereby depressing end 54 and raising end 56. This action will also push cam surfaces 34 downwardly through central opening 36. The distance between the two cam surfaces 34 is greater that the distance between the rods in the position shown in Figure 5 and thus the central portions of the rods are pushed apart by the cam surfaces 34 (see Figure 6). Because the lands 32 have a fixed distance between them, they prevent the two ends of the rods from moving outwardly when the central portion of the rods are urged apart by cam surfaces 34. This results in the rods 20 flexing and causes the ends of the rods to be moved together in the vicinity of the openings 18. The reduction in the spacing between the rods 20 at their ends is possible because the ends of the rods are merely supported on ledges 30 and are freely slidable over such ledges.
[0017] As can be seen from Figures 4 and 6, the separation between the rods 20 in the openings 18 when the arm is in the position shown in Figures 4 and 6 is less than the diameter to the prongs 10 of the file. The rods 20 will therefore grip the prongs and prevent the compressor bar (and any underlying documents) from moving.
[0018] As will be seen for example in Figure 9, the cam surfaces have rectangular sections standing proud of the rest of the cam surface. Also, it can been seen that the two cam surfaces taper downwardly so that when the end 54 of rocker arm 22 is pressed down, the cam surfaces push the rods apart. When the rods are unflexed (see Figures 3 and 5), the rectangular sections of cams 34 lie just above the rods 20 (as used herein, the terms "above" and "below" refers to the compressor bar in its normal orientation, as shown in Figure 3). When the rods are in their flexed position (see Figures 4 and 6), the rectangular surfaces of cams 34 are located below the rods; the engagement of the rods against the rectangular sections prevents the tension in the rods pushing the cam surfaces upwardly.
[0019] As indicated above, the rocker arm 22 is pivotally attached to the base 17 by means of the notches 44 of the side lugs 40 being engaged with surface 52 of the U-shaped slot 38. The notches 44 are prevented from disengaging from the surfaces 52 as a result of the abutment of the T-shaped member 46 against the surface 53 of the slot 38. However, an additional mechanism retaining the arm 22 can be seen in Figure 5. The T-shaped member 46 has a cross piece 60 which engages the undersides of the rods 20 (i.e. the sides of the rods opposite to the rocker arm 22) and this engagement prevents the rocker arm 22 from being pulled out away from the base 17. When the rods are in their flexed state (see Figure 6) the cross piece 60 need not lie under the rods since, as a result of the rods having been pushed apart, the spacing between the rods may be greater than the width of the cross piece 60. However, the additional locking mechanism provided by the cross piece is not necessary when the rods are in their flexed state because the notches 44 are prevented from becoming disengaged with the corresponding surfaces 52 by virtue of the engagement of the cam surfaces 34 with the rods. Such an arrangement removes the requirement to bend the fingers 42 of the lugs outwardly so that they overlie the part of the base 17 adjacent to the slot 38, as was necessary in the prior art in order to retain the arm within a slot in the base.
[0020] The base also includes a spacer 62 that prevents the separation between the rods falling below a minimum when they are in their unflexed state. Thus, spacer 62 prevents the rods from falling out and also maintains sufficient spacing in the region of the openings 18 to allow the prongs of the file 10 to move freely through the openings 18 without being obstructed by the rods. As can also be seen from Figure 5, the central stem section 64 of the T-shaped member 46 also fulfils the same function.
a base (17) having a pair of spaced-apart openings (18) though which the prongs can extend;
a pair of resilient rods (20) held within the base and extending between the pair of openings;
an arm (22) pivotally attached to the base by a connection means and comprising means (34) for flexing the rods at a position between the two openings, the arm being moveable between a first position in which the flexing means (34) flexes the rods (20) and a second position in which the rods (20) are not flexed or are flexed to a lesser extent; and
two sets of lands (32), each set being attached to the base between the flexing means (34) and the respective openings (18), said lands being positioned to provide a fulcrum about which each rod can pitch whereby the flexing of the rods (20) by the flexing means (34) causes the spacing between the rods in the openings (18) to alter between a first spacing in which the rods can grip prongs extending through the openings and a second spacing that is wider than the first spacing,
characterised in that:the connection means between the arm (22) and the base (17) comprises a connection member (46) secured to the arm (22) and having:
a cross-piece (60) that engages the rods (20) on the side of the rods remote from the arm (22) at least when the arm is in the second position to prevent the arm being separated from the base in the said second position, and
a shaft (64) connecting the cross piece to the rest of the arm (22).