Abstract:
A web of undulate wire is converted into a series of coherent C-shaped binders of the type known by the trademark Wire-O and used to bind stacks of paper sheets or the like in the making of steno pads, brochures, calendars and similar stationery products by continuously moving the web lengthwise at a constant or variable speed, by imparting to successive increments of one marginal portion of the moving web a concavo-convex shape in stepwise fashion so that the one marginal portion resembles (in cross-section) one-half of the letter C, and by thereupon imparting to successive increments of the other marginal portion of the moving web a concavo-convex shape in stepwise fashion so that the thus converted other marginal portion becomes a mirror image of the converted one marginal portion. The imparting steps include deforming the respective marginal portions from the inner toward the outer edges thereof.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to a method and apparatus for making wire binders for steno pads, calendars, brochures and like commodities wherein a stack of sheets is held together along one edge so that the sheets can be flipped about an axis which is defined by the properly inserted binder. More particularly, the invention relates to improvements in a method and apparatus for converting a length of wire into an undulate web and for thereupon converting the undulate web into a substantially C-shaped body which is ready to be subdivided into discrete binders. 
     It is already known to convert a straight metallic or plastic wire, which is withdrawn from a barrel, reel or another suitable source of supply, into a meandering or undulate web whose loops are located in or can be moved into a common plane. Such web is thereupon bent along an axis which extends lengthwise of the web to achieve the conversion into a C-shaped or trough-shaped structure having prongs along one or both marginal portions so that it can be introduced into the registering perforations of stacked sheets preparatory to conversion of individual C-shaped constituents into rings. The conversion of straight wire into an undulate or meandering web can be carried out in a machine of the type disclosed in the commonly owned U.S. Pat. No. 4,165,767 granted Aug. 28, 1979 to Seaborn and Lemburg. The web is converted into a C-shaped structure by resorting to several deforming tools, e.g., two pressing tools, and to a conveyor system which advances the undulate web through the deforming station in stepwise fashion. During each interval between successive stepwise advances of the undulate web, the marginal portions of such web are treated by one of the deforming tools and the median portion or the regions bounding the median portion of the web are thereupon treated by another deforming tool. Reference may be had to U.S. Pat. No. 4,047,544 granted Sept. 13, 1977 to Paul Seaborn et al. A drawback of such intermittently operated apparatus is that their output is relatively low. Therefore, apparatus of the type disclosed in U.S. Pat. No. 4,047,544 are not directly coupled to machines which can turn out undulate web of metallic or plastic wire at a relatively high rate of speed. In other words, the patented apparatus cannot be used as a constituent of a complete production line which converts wire into binders, which assembles or otherwise treats stacks of sheets, and which inserts binders into discrete stacks. Certain stacks can be held together by a single binder, and certain other stacks are held together by two or more converted C-shaped or trough-shaped binders. 
     OBJECTS AND SUMMARY OF THE INVENTION 
     An object of the invention is to provide a novel and improved method of treating wire preparatory to conversion into discrete sections of binders for stacks of paper sheets or the like. 
     Another object of the invention is to provide a method which can be resorted to for the production of a large number of wire binders per unit of time. 
     A further object of the invention is to provide a method which renders it possible to move the wire continuously during conversion into a C-shaped or trough-shaped body. 
     An additional object of the invention is to provide a novel and improved apparatus for the practice of the above outlined method. 
     Another object of the invention is to provide an apparatus which can be resorted to for conversion of straight metallic or plastic wire into a C-shaped or trough-shaped web in a small area, while the material is in a continuous motion, and with a high degree of reproducibility. 
     A further object of the invention is to provide the apparatus with novel and improved means for converting a web of undulate wire into a C-shaped body which can be subdivided into binders of desired length. 
     One feature of the invention resides in the provision of a method of converting an elongated web of undulate metallic or plastic wire which includes a pair of longitudinally extending marginal portions into a series of interconnected substantially C-shaped binders which can be used to connect the sheets of a stack of paper sheets or the like. The method comprises the steps of moving the web lengthwise (such step preferably includes continuously conveying the web lengthwise along a predetermined path), gradually imparting to successive increments of one marginal portion of the web a concavo-convex configuration which, in cross-section, resembles or matches substantially one-half of the letter C, and gradually imparting to successive increments of the other marginal portion of the web a concavo-convex configuration which is a mirror image of the concavo-convex configuration of the one marginal portion. 
     One of the imparting steps preferably follows the other imparting step, and each imparting step preferably includes deforming the web (e.g., by rolling) in a direction toward the outer edge of the respective marginal portion. At least one imparting step preferably comprises deforming the respective marginal portion in a plurality of discrete stages. In accordance with a presently preferred embodiment of the method, each of the imparting steps includes deforming successive increments of the respective marginal portion in stepwise fashion (e.g., between the peripheral surface of a rotating disc-shaped anvil and the peripheral surfaces of several successive rolls which are driven to rotate about their respective axes and whose axes make different angles with the axis of the anvil). 
     The method preferably further comprises the step of tensioning successive increments of the web in the longitudinal direction of the wire prior to at least one of the imparting steps. This can be carried out by resorting to a stretching wheel which advances successive increments of the web toward the periphery of the respective disc-shaped anvil. 
     It is also within the purview of the invention to utilize a web whose central portion remains flat so that the ultimate product resembles, in cross-section, an elongated capital letter C. 
     The web which is converted into a body having a cross-sectional outline resembling the letter C is ready to be severed to yield discrete binders of desired length which can be introduced into the perforations of a stack of paper sheets or the like prior to undergoing further deformation which results in conversion of the loops of each binder into rings. Finished binders of the type to which the present invention pertains are sold under the registered trademark Wire-O. 
     The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The improved apparatus itself, however, both as to its construction as well as its mode of operation, together with additional features and advantages thereof, will be best understood upon perusal of the following detailed description of certain specific embodiments with reference to the accompanying drawing. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     FIG. 1 is an exploded schematic perspective view of an apparatus which embodies the invention; 
     FIG. 2 is an enlarged front elevational view of the conveying, stretching and deforming means in the apparatus of FIG. 1; 
     FIG. 3 is an axial sectional view of the anvils of the two deforming means in the apparatus of FIG. 1; 
     FIG. 4 is an enlarged fragmentary partly sectional view of a detail in the structure of FIG. 2; 
     FIG. 5 is a sectional view as seen in the direction of arrows from the line V--V of FIG. 4; and 
     FIGS. 6 through 19 illustrate successive stages of conversion of a portion of undulate wire web into a portion of a C-shaped binder. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The apparatus of FIG. 1 comprises a first or primary deforming unit 1 which continuously converts a continuous strand of plastic or metallic wire 2 (such strand can be drawn off a reel in a barrel 102 or another suitable source) into an undulate flat web 2a. The undulations or loops of the web 2a are or can be located in a common plane, i.e., the wire 2 is converted into a relatively narrow web with portions of wire 2 extending substantially at right angles to the longitudinal direction of the web. 
     The apparatus of FIG. 1 further comprises a second or secondary deforming unit 3 which serves to covert the web 2a into a C-shaped or trough-shaped product 2c constituting a series of interconnected binders. This product (hereinafter called a continuous binder or simply binder for short) can be used to connect the sheets of a stack to each other, i.e., to convert such sheets into a steno pad, a calendar, a pamphlet, a brochure or the like. The conversion of the web 2a into the continuous binder 2c is carried out in such a way that the marginal portions 2A, 2B (FIG. 3) of the web are gradually bent toward each other so that the binder 2c exhibits a plurality of prongs at each of its edges. Such prongs can be inserted into the perforations of a stack of sheets prior to conversion of C-shaped portions of the binder into rings. The axis or axes about which the web 2a is bent to form the binder 2c extend lengthwise of the web. 
     The first or primary deforming unit 1 comprises two rotary carriers 6 and 7. The carrier 7 surrounds and is slightly eccentric with respect to the carrier 6. The front surface 6a and 7a of the carriers 6 and 7 are located in a common plane; such surfaces carry annuli of deforming pins and/or dogs (not specifically shown). Reference may be had to the commonly owned U.S. Pat. No. 4,165,767 granted to Seaborn and Lemberg on Aug. 28, 1979. The disclosure of this patent is incorporated, in its entirety, by reference in the disclosure of the present application. The rotary carriers 6, 7 are caused to rotate with each other due to the presence of torque transmitting or entraining pins which connect the carrier 7 to the carrier 6 (if the latter is driven) or vice versa. The drive means for the rotary carriers 6 and 7 comprises a shaft 8. 
     A looping arm 9 with two orbiting looping elements 9a is secured to a shaft 11. This looping arm is adjacent to the surfaces 6a, 7a in the region of minimal distance between the deforming elements on the carriers 6 and 7. A pivotable stripping finger 13 is mounted on a shaft 12 which is normal to the shafts 8 and 11. The shaft 12 is turnable by link 14 which is articulately connected to a strap 16 on an eccentric 18 secured to a shaft 17. When the shaft 17 rotates, the eccentric 18 and the strap 16 cause the link 14 to turn the shaft 12 back and forth. 
     The shaft 17 drives the shaft 11 via transmission 19 and receives torque from a toothed belt or chain drive 21. The latter receives motion from an intermediate shaft 22 which is driven by an electric motor 28 or another suitable prime mover by way of a second toothed belt or chain drive 27. The intermediate shaft 22 further transmits torque to the shaft 8 via chain or toothed belt drive 23, shaft 24 and transmission 26. 
     The second deforming unit 3 embodies the present invention and comprises two coaxial disc-shaped deforming anvils 32a and 32b (hereinafter called discs) which are mounted on a common shaft 31. The peripheral surfaces of the discs 32a, 32b are respectively formed with recesses or cutouts 33a, 33b (see FIGS. 3 and 4) for reception of successive increments or portions of the undulate web 2a leaving the first deforming unit 1. An intermediate stage of deformation of the web 2a (after it leaves the disc 32a) is shown at 2b. 
     Those sides (34a, 34b) of the discs 32a, 32b which face each other (see FIG. 3) are formed with annular projections 36a, 36b having a substantially semicircular cross-sectional outline. The annular projections 36a, 36b are inwardly and rather closely adjacent to the respective peripheral recesses 33a, 33b. 
     The peripheral surface of the disc 32a travels past a first set of four deforming tools in the form of rolls 37a, 38a, 39a, 41a and a second set of deforming tools or rolls 42a, 43a, 44a. Analogously, the peripheral surface of the disc 32b travels past a first set of four deforming tools or rolls 37b, 38b, 39b, 41b and a second set of deforming tools or rolls 42b, 43b, 44b.  The axes of the shafts for the deforming rolls 37a, 37b, 38a, 38b, 39a, 39b, 41a, 41b are parallel or nearly parallel to the axis of the common shaft 31 for the discs 32a, 32b, and the axes of deforming rolls 42a, 42b, 43a, 43b, 44a, 44b are radial or substantially radial to the respective discs 32a, 32b. The construction, configuration and mounting of the deforming rolls 37a to 44b are such that each next-following deforming roll overlies the respctive annular projection 36a or 36b to a somewhat greater extent than the preceding deforming roll (see FIGS. 6-19). The term &#34;overlies&#34; is intended to denote as considered from the inner toward the outer side of the respective annular projection, i.e., from the inner edge toward the outer edge (2AA, 2BB) of the respective marginal portions (2A, 2B) of the web 2a. 
     Each of the discs 32a, 32b is associated with a rotary catcher 47a, 47b and a rotary stretching or tensioning wheel 46a, 46b. As shown in FIGS. 1, 2, 4 and 5, the tensioning wheels are disposed between the respective catchers and the associated discs. Also, the catchers 47a, 47b are located ahead of the corresponding discs 32a, 32b, as considered in the direction of lengthwise movement of the webs 2a, 2b. 
     The shaft 31 for the discs 32a, 32b receives torque from a toothed belt or chain drive 48 which, in turn, receives motion from a shaft 51 driven by a further toothed belt or chain drive 49. The latter receives motion from the shaft 24 (input shaft of the transmission 26) by way of a universal joint 53 (e.g., a Cardan shaft) and a transmission 52. 
     The tensioning wheels 46a, 46b and the rotary catchers 47a, 47b are respectively mounted on shafts 54a, 54b and 56a, 56b. The shafts 54a, 56a carry mating gears 57a, and the shafts 54b, 56b carry mating gears 57b. The shafts 54a, 54b receive torque from the common shaft 31 for the discs 32a, 32b via pairs of mating gears 58a, 58b. Additional toothed belt or chain drives 59a, 59b respectively connect the shafts 54a, 54b with shafts 61a, 61b for the deforming rolls 41a, 41b. Additional gears (not specifically shown) transmit torque from the shafts 61a, 61b to the shafts of the deforming rolls 39a, 38a, 37a and 39b, 38b, 37b. In addition, the shafts 61a, 61b drive shafts 63a,  63b via chain or toothed belt drives 62a, 62b. The shafts 63a, 63b, respectively, constitute the input elements of transmission 64a, 64b whose output elements 66a, 66b carry the deforming rolls 43a, 43b. The shafts 66a, 66b of the deforming rolls 43a, 43b, respectively, transmit torque to the deforming rolls 42a, 44a and 42b, 44b by way of suitable gear trains (not shown). 
     The construction of the catcher 47a and tensioning wheel 46a is respectively similar or identical to that of the catcher 47b and tensioning wheel 46b. Therefore, the drawing merely shows the details of the catcher 47a and tensioning wheel 46a, i.e., of those elements which are associated with the disc 32a. As best shown in FIG. 5, the catcher 47a comprises two spaced-apart circular parallel saw blade-like portions 71a&#39;, 71a&#34; which are disposed at the respective ends of a cylindrical hub 72a forming part of the shaft 56a. The teeth 73a&#39;, 73a&#34; of the portions 71a&#39;, 71a&#34; have a spacing T1 (see FIG. 4) which exceeds the spacing T of the loops of the web 2a. 
     The tensioning wheel 46a comprises two spaced-apart parallel disc-shaped portions 74a&#39;, 74a&#34; which are disposed at the respective axial ends of a hub 76a forming part of the shaft 54a. The portions 74a&#39;, 74a&#34; are respectively formed with circumferential cutouts or tooth spaces 77a&#39;, 77a&#34; for reception of portions of the web 2a. The spacing T2 between the centers of neighboring cutouts 77a&#39; or 77a&#34; is slightly less than the spacing T of the loops of the web 2a. 
     A stationary sheet metal shroud 78a prevents accidental or unintentional removal of the web 2a from the cutouts 77a&#39;, 77a&#34;. These cutouts are longer than the recesses 33a of the disc 32a. The spacing T between the centers of neighboring recesses 33a matches the spacing of the loops of the web 2a. 
     That side of the disc 32a which faces away from the annular projection 36a and the peripheral surface of the disc 32a are surrounded by a stationary cover 79a which has openings 81a in the region of the tensioning wheel 46a, in the region of the deforming rolls 36a-39a, 41a-44a, and in the region where the web 2b leaves the disc 32a. The cover 79a prevents escape of the web 2a from the recesses 33a and this cover also prevents axial shifting of the web 2a in the recesses 33a during deformation of the wire under the action of the rolls 37a-39a and 41a-44a. A similar cover is provided for the disc 32b. 
     The guide means for directing the web 2a toward the catcher 47a comprises two elongated strips 82a (see FIG. 4). The wire of the web 2a is pushed or pulled toward the catcher 47a while advancing in the channel between the strips 82a. Similar guide means (not shown) is provided to advance the web 2b from the disc 32a into the range of teeth on the catcher 47b. The manner of continuously driving the discs 32a, 32b, the catchers 47a, 47b and the tensioning wheels 46a, 46b is such that the quotients of the respective peripheral speeds and the spacings between the respective recesses, cutouts or teeth are identical. 
     The operation is as follows: 
     The elements 9a of the orbiting arm 9 drape the wire 2 around the pins of the inner carrier 6 which is driven by the shaft 8. The stripping finger 13 fully transfers the wire onto the pins of the member 6 and the wire is intercepted by the pins or dogs of the rotating outer carrier 7. Such wire is draped around the dogs under the action of the elements 9a. A stationary cam (not shown) removes the undulate web 2a from the pins and/or dogs of the carriers 6 and 7. The configuration of loops of the web 2a is fixed because the loops are stretched as a result of eccentrically of the carrier 6 relative to the carrier 7. Reference may be had to the aforementioned commonly owned U.S. Pat. No. 4,165,767. 
     The web 2a enters the channel between the strips 82a and advances toward the continuously rotating catcher 47a whose teeth 73a&#39;, 73a&#34; enter the larger loops of the web to push successive pairs of closely adjacent transversely extending web portions into successive recesses 77a&#39;, 77a&#34; of the continuously rotating tensioning wheel 46a. Since the spacing T2 between the centers of neighboring recesses 77a&#39;, 77a&#34; is slightly less than the spacing T of neighboring loops of the web 2a, the web 2a on the tensioning wheel 46a is subjected to a tensional stress which insures that, in the region of transfer from the wheel 46a to the periphery of the disc 32a, the wire of the web 2a lies against the leading surfaces in the recesses 77a&#39; and 77a&#34;. Such wire is guided by the edge portion 79a&#39; of the cover 79a. This edge portion extends between the portions 74a&#39; and 74a&#34; of the tensioning wheel 46a, and its purpose is to guide successive increments of the web 2 a into the peripheral cutouts 33a of the disc 32a. The rolls 37a, 38a, 39a, 41a, 42a, 43a and 44a bend or flex the loops at one outer edge 2AA of the web 2a in stepwise fashion (while the web 2a moves continuously). The deformation of the web 2a progresses from the center 2D toward the one outer edge 2AA of the respective marginal portion 2A in a manner as shown in FIGS. 6, 7, 8, 9, 10, 11, 12. Successive increments of the thus obtained web 2a are removed from the disc 32a and are advanced into the range of the catcher 47a whence the web 2b advances toward and onto the disc 32b via tensioning wheel 46b. The loops at the other marginal portion 2B of the web 2b are deformed by the rolls 37b, 38b, 39b, 41b, 42b, 43b, 44b, again starting at the center 2D of the web 2b and progressing toward the outer edge 2BB of the marginal portion 2B. The deforming action of the rolls 37b-39b, 41b- 44b is shown in FIGS. 13, 14, 15, 16, 17, 18 and 19. The thus obtained C-shaped or trough-shaped binder 2c is ready to be severed to yield sections of requisite length which are thereupon inserted into rows of perforations and deformed to form rings which connect the sheets of a stack along a selected edge of the stack. The subdivision into sections takes place subsequent to removal from the disc 32b. The details of the machine which connects the sections of binder 2c with stacks of sheets form no part of the invention. Reference may be had to U.S. Pat. No. 4,020,516 granted May 3, 1977 to Gomez or to U.S. Pat. No. 4,047,544 granted Sept. 13, 1977 to Seaborn et al. 
     FIG. 12 shows that the fully converted marginal portion 2A of the web 2a has assumed to concavo-convex configuration 102A resembling one-half of the letter C, and FIG. 19 shows that the fully converted marginal portion 2B has assumed a concavo-convex configuration 102B which is a mirror image of the converted marginal portion 102A. The central portion 2D of the web 2a has remained flat so that the finished product 2c resembles an elongated capital letter C. 
     The manner in which the rolls 37a, 38a, 39a, 41a, 42a,  43a, 44a gradually deform the marginal portion 2A to convert this marginal portion into the arcuate portion 102A is shown in FIGS. 6 to 12. Such deformation is effected by bending the marginal portion 2A about the projection 36a at the one side 34a of the disc 32a. The deformation of successive increments of the web 2a begins close to the central portion 2D and progresses stepwise toward the outer edge 2AA of the marginal portion 2A. The manner in which the rolls 37b, 38b, 39b, 41b, 42b, 43b, 44b deform the marginal portion 2B by rolling it around the projection 36b of the disc 32b is shown in FIGS. 13 to 19 and is analogous to deformation of the marginal portion 2A. 
     It will be noted that, in accordance with the present invention, the web 2a and/or 2b can move continuously during gradual conversion of its marginal portions 2A, 2B into concavoconvex configurations 102A, 102B which are mirror images of each other (with respect to a plane extending midway of the central portion 2C and halving the final product 2c). In addition, the conversion of successive increments of the marginal portions 2A, 2B into the corresponding concavo-convex configurations 102A, 102B is effected gradually (stepwise) and in such a way that the deformation (by bending around the projections 36a, 36b) progresses from the inner edges toward the outer edges 2AA, 2BB of the respective marginal portions. Such sequence of steps renders it possible to directly couple the unit 1 with the unit 3, and to directly couple the unit 3 with a machine which inserts discrete Wire-O binders into the perforations of stacked paper sheets or the like. The output of the deforming unit 3 is surprisingly high, and the quality of the product 2c is quite satisfactory. 
     The mounting of discs 32a, 32b on a common drive shaft 31 contributes to compactness of the improved apparatus. The provision of means which drive the shafts of the deforming rolls 37 and 38 and derive motion from the shaft 31 or from a component receiving torque from the means for driving the shaft 31 also contributes to compactness and simplicity of the improved apparatus. The relatively narrow peripheral recesses of the discs 32a, 32b insure that the increments of the web 2a are properly held against uncontrolled stray movements during conversion of the marginal portions 2A, 2B into concavo-convex configurations 102A, 102B. During transfer of successive increments of the web 2a and 2b from the tensioning wheels 46a, 46b into the recesses 33a, 33b of the discs 32a, 32b, such increments are compelled to assume predetermined positions so that the apparatus can produce a series (2c) of interconnected C-shaped or trough-shaped binders with a high degree of reproducibility. This is due (at least in part) to the fact that each spacing or distance T2 is less than a distance or spacing T. As a rule, the increments of the web 2a or 2b which are transferred onto the wheels 32a, 32b are caused to lie against the leading edges of teeth between the recesses 33a, 33b. The increments also lie against the teeth of the catchers 47a, 47b. This insures predictable transfer or successive increments or hairpin-shaped loops of the web 2a and 2b onto the discs 32a or 32b. 
     Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic and specific aspects of my contribution to the art and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the appended claims.