Patent Publication Number: US-6659927-B2

Title: Folding presser assembly

Description:
BACKGROUND OF THE INVENTION 
     1. Technical Field of the Invention 
     This invention generally relates to a presser assembly for a blanking operation, and, more particularly, to a presser assembly for supporting blanking scrap, such as carton or paper blanking scrap during a blanking operation. 
     2. Description of Related Art 
     In the manufacture of cartons and paper products, small sheets of material are typically cut out of larger sheets. These smaller sheets are known as blanks that, in turn, may be further formed into various shapes, such as, by way of example, into boxes. The blanks are formed during a process known as a blanking operation. In a blanking operation, the blanks are cut, but not removed, from the large sheet of carton or paper material. After the blanks have been cut, the sheet is positioned over a frame for support. The frame typically includes large openings that correspond in size and in position to the blanks previously cut. Below the frame is a mechanism for stacking the blanks. In order to knock the carton blanks from the sheet of material and hold the scrap material, what is known in the art as a presser assembly is used. The presser assembly includes a support tool having a presser member and a presser rail depending therefrom. The presser rail is biased away from the support tool. As the support tool is lowered, the presser rail engages the sheet of material such that the sheet of material is secured between the presser rail and the frame. The support tool continues to be lowered such that the presser member engages the blanks and knocks the blank out of the sheet of material. The carton blanks fall onto a stacking mechanism wherein the blanks are stacked. 
     If the presser rail does not adequately hold the blanking scrap, the scrap may fall onto the stacking mechanism. A carton blanking scrap in the stacking mechanism may jam the mechanism thereby causing downtime and expense. In order to securely hold the carton blank scrap, the present day presser rails are interconnected to the support tool by a plurality of guide cylinders. Each guide cylinder biases the presser rail away from the support tool. This gives the presser rail a certain amount of flexibility when engaging the carton blanking scrap. However, even with this limited flexibility, present day presser rails and assemblies have been found to be inadequate and require substantial assembly and various parts. An example of such a presser assembly is provided in U.S. Pat. No. 5,529,565, the subject matter of which is incorporated herein in its entirety by reference. 
     The prior art fails to provide a presser assembly that offers a simple configuration which is less costly to manufacture and easier to assemble, and which is further easily and efficiently mountable to a backer board of a blanking device. 
     SUMMARY OF THE INVENTION 
     It is a purpose of the present invention to solve the above-mentioned problems. 
     To achieve the above purpose, the present invention provides a presser assembly for supporting blanking scrap during a blanking operation. The presser assembly includes: a support rail; a presser rail connected to the support rail; and a connecting rail connecting the presser rail to the support rail and being adapted to pivot with respect to at least one of the support rail and the presser rail through a predetermined pivot angle range. The pivot angle range is for changing a distance between the support rail and the presser rail to thereby selectively affect a folding and an unfolding of the presser assembly during the blanking operation. 
     The present invention further encompasses a kit for forming a presser assembly for supporting blanking scrap during a blanking operation. The kit includes: a support rail; a presser rail adapted to be connected to the support rail; and a connecting rail adapted to connect the presser rail to the support rail and adapted to pivot with respect to at least one of the support rail and the presser rail in an assembled state of the presser assembly. The pivoting is through a predetermined pivot angle range for changing a distance between the support rail and the presser rail thereby selectively effecting a folding and an unfolding of the presser assembly during the blanking operation. 
     Additionally, the present invention provides a method of using the presser assembly described above. The method comprises the steps of: pivoting the connecting rail with respect to at least one of the support rail and the presser rail for reducing an angle defined therebetween thereby folding the presser assembly for reducing a distance between the presser rail and the support rail; and pivoting the connecting rail with respect to at least one of the support rail and the presser rail for increasing an angle defined therebetween thereby unfolding the presser assembly for increasing a distance between the presser rail and the support rail. 
     Moreover, the present invention provides a presser assembly for supporting blanking scrap during a blanking operation, where the presser assembly includes: a support means; a presser means connected to the support means and supported thereby; and a connecting means for connecting the presser rail to the support rail and being adapted to pivot with respect to the presser rail through a predetermined pivot angle range for changing a distance between the presser rail and the support rail thereby selectively affecting a folding and an unfolding of the presser assembly during the blanking operation. 
     Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. dr 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention will become more fully understood from the detailed description given herein below and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein: 
     FIG. 1 is a front-elevational view of a preferred embodiment of a presser assembly according to the present invention; 
     FIG. 2 is a perspective, partially cut-away portion of the presser assembly according to FIG. 1 showing a biasing mechanism according to a preferred embodiment of the present invention; 
     FIG. 3 is a view similar to a mirror image of FIG. 2 showing a sliding mechanism according to a preferred embodiment of the present invention; 
     FIG. 4 is a perspective view of a glide support according to a preferred embodiment of the present invention; 
     FIG. 5 a  is a view of a support end of one of the connecting rails of FIG. 1 shown connected to the support rail with the connecting rail in cross-section and partial cutaway; 
     FIG. 5 b  is a front-elevational view of the guide pin shown in FIG. 5 a  according to a preferred embodiment of the present invention; and 
     FIG. 5 c  is a front-elevational view of one of the locking rings shown in FIG. 5 a  according to a preferred embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The present invention overcomes the problems of the prior art by providing a presser assembly of simple construction having fewer components than presser assemblies of the prior art which use guide cylinders. The presser assembly of the present invention therefore tends to advantageously be less costly to manufacture and easier to assemble. The presser assembly according to the present invention is further, in an advantageously manner, easily and efficiently mountable to a backer board of a blanking device. 
     In order to achieve the above advantages, the present invention provides a presser assembly that includes at least one, and preferably two, connecting rails between a support rail and a presser rail. The connecting rail establishes and maintains a distance between the support rail and the presser rail, and is advantageously pivotable with respect to at least one of the support rail and the presser rail for allowing the presser assembly to be folded and unfolded thereby reducing a distance between the support rail and the presser rail. An unfolding of the presser assembly would then involve a pivoting of the connecting rail with respect to at least one of the support rail and the presser rail such that a distance between the support rail and the presser rail is increased. The ability to decrease and increase the distance between the support rail and the presser rail, as recognizable by one skilled in the art, advantageously allows an expedient blanking operation to take place. The fact of using at least one, and preferably two connecting rails according to the present invention greatly simplifies the construction of a presser assembly and makes assembly and mounting of the presser assembly simpler and more efficient. 
     By “rail,” what is meant in the context of the present invention is any rigid member the length of which does not vary during a folding and unfolding of the presser assembly. Furthermore, a distance between the support rail and the presser rail may be “changed” according to the present invention by moving the support rail and the presser rail with respect to one another in either a translational movement and/or a pivoting movement of the support rail with respect to the presser rail. In either case, a distance between the support rail and the presser rail is changed. In addition, by “folding” the presser assembly, what is meant in the context of the present invention is a pivoting of parts of the presser assembly with respect to one another to draw the parts together and to make the assembly more compact. 
     Turning now to the drawings, and more particularly, to FIG. 1, a preferred embodiment of the present invention is shown. As seen in FIG. 1, the preferred embodiment includes a presser assembly  10  for supporting blanking scrap during a blanking operation. Presser assembly  10  includes a support rail  12  and a presser rail  14  connected to the support rail as shown. At least one, and preferably two, connecting rails  16 ,  18  connect the presser rail  14  to the support rail  12 . In the shown preferred embodiment of the present invention, a first connecting rail  16  and a second connecting rail  18  connect the presser rail  14  to the support rail  12  respectively at the first end  20  and at the second end  21  of the presser rail  14 . The first connecting rail  16  and the second connecting rail  18  each are adapted to independently pivot with respect to at least one of the support rail  12  and the presser rail  14  for changing a distance between the support rail and the presser rail thereby enabling folding the presser assembly during the blanking operation. In the shown preferred embodiment, the first connecting rail  16  and the second connecting rail  18  are pivotable with respect to presser rail  14  at respective pivot points  22  and  24  as shown. The support rail  12  and the presser rail  14  are biased away from one another by a biasing mechanism  26 . The biasing mechanism as shown is coupled to presser ends  28  and  30  of the first connecting rail  16  and the second connecting rail  18 , respectively. However, it is to be understood that the present invention includes within its scope a biasing mechanism that is coupled to at least one of two ends of one or more connecting rails connecting the support rail with the presser rail. In the preferred embodiment of the present invention, the biasing mechanism  26  comprises a torsion spring  32 , shown in phantom in FIG. 1, at only the presser end of the first connecting rail  16 , it being understood that a torsion spring (not shown) is also provided at presser end  30 . Each torsion spring includes a distal arm  34  and a proximal arm  36 , the distal arm  34  resting against a corresponding one of the first connecting rail  16 , there being a similar arrangement for the second connecting rail  18 . The proximal arm  36  rests against a trough  38  of the presser rail  14 . Each torsion spring  32  in this way biases the corresponding connecting rail to establish, with other separation limiting means, a default distance D between the support rail  12  and the presser rail  14 , the connecting rails in this way defining an angle a between each connecting rail and the presser bar. The angle α at the default distance is preferably from about 30° to about 60°, for example, from about 40° to about 50°. More preferably, the angle α is about 45 degrees. As shown in FIG. 1, the connecting rails, presser rail, support rail, and the presser assembly are in their default modes, or positions. 
     Preferably, according to the present invention, biasing mechanisms  26  further each include a first pin  40 , only one of which is depicted in FIG. 1, each one respectively extending through a respective presser end  28  or  30  of the first connecting rail  16  and the second connecting rail  18  for pivotally securing the first connecting rail and the second connecting rail to the presser rail. While only one pin  40  is shown in FIG. 1, it is to be understood that there is a pin  40  provided to secure the torsion spring  32  to each presser end of each of the first connecting rail  16  and the second connecting rail  18 . The pin  40  preferably extends through holes  42  in each of the presser ends  28  and  30 , and through corresponding holes  44  at the first end  20  and second end  21  of the presser rail  14 . It is to be understood that, similar to pin  40 , although only one series of holes  40  and  42  are shown in FIG. 1, identical holes are provided at both the first end  20  and the second end  21  of the presser rail  14 , and at both presser ends  28  and  30  corresponding to both connecting rails  16  and  18 . 
     Referring now to FIG. 2, a perspective view is provided of the presser assembly of FIG. 1 in its default mode showing a portion thereof adjacent the first end  20  of presser rail  14 . It is to be understood, however, that, according to the preferred embodiment of the present invention, each end of the presser assembly is identical to or a mirror image of the other end thereof. Therefore, descriptions regarding FIG.  2  and pertaining to portions of the presser assembly adjacent first end  20  of presser rail  14  apply equally to the portions of the presser assembly adjacent second end  21  of presser rail  18 . As shown in FIG. 2, the presser rail is preferably an elongated member defining a trough  46  therein. The trough is more preferably defined between two parallel sidewalls  48  and a bottom wall  50 , presser ends  28  and  30  resting against bottom wall  50 , and proximal arm  26  of torsion spring  32  further resting against bottom wall  50 . Referring back to FIG. 1, the first connecting rail  16  and the second connecting rail  18  each further have respective support ends  52  and  54  and are further pivotally connected to the presser rail such that presser ends  28  and  30  thereof are disposed in the trough  46 . 
     Referring now to FIG. 3, a portion of presser assembly  10  adjacent second end  21  of presser rail  14  is shown. Similar to FIG. 2, descriptions regarding FIG.  3  and pertaining to portions of the presser assembly adjacent second end  21  of presser rail  18  apply equally to the portions of the presser assembly adjacent first end  20  of presser rail  16 . As shown in FIG. 3, according to a preferred embodiment of the present invention, the support rail  12  is an elongated member defining a trough  56  therein, the first connecting rail  16  and the second connecting rail  18  each being slidably guidable within the trough at support ends thereof. Trough  56  is defined between parallel sidewalls  58  and top wall  60  of the support rail  12 . 
     Support ends  52  and  54  of connecting rails  16  and  18  are preferably made slidably guidable in trough  56  by providing at least one guide groove in support rail  12  according to the present invention. Additionally, a sliding mechanism  62  is provided for effecting a sliding of the support ends of the first connecting rail and the second connecting rail within the trough  56 . The sliding mechanism preferably includes a guide pin  64  extending through a respective support end  52  or  54 . As shown in FIG. 3, the pins  64  are slidably guidable within the at least one guide groove, as will be explained in further detail below. 
     According to the shown preferred embodiment of the present invention in FIG. 3, the at least one guide groove includes two pairs of grooves  66 , one pair of which is shown in FIG. 3. A first pair of the two pairs of grooves is preferably disposed adjacent the support end  52  of the first connecting rail  16 , and is configured for guiding one of the guide pins  64  therein. The second pair  66  of the two pairs is preferably disposed adjacent the support end  54  of the second connecting rail  18  and is configured for guiding the other one of the guide pins  64  therein. Each pair  66  of guide grooves more preferably includes two opposite and facing elongated holes, grooves, or slots  68 , each defined in a respective sidewall  58  of the support rail  12 . Referring now to both FIGS. 1 and 3, as the connecting rails  16  and  18  are pivoted so as to reduce angle α and reduce default distance D, each guide pin  64  slides forward in its corresponding slot  68 , with each lateral part of each slot  68  serving as a stop for its corresponding guide pin. Therefore, in a default mode of the connecting rails, outer edges  70  of each slot  68  determine a stopping position of each connecting rail as it is biased outward, as readily recognizable by one skilled in the art. 
     Referring back to FIG. 3, the sliding mechanism  62  further preferably includes a glide support  72  for each of the connecting rails  16  and  18 , the glide support for connecting rail  18  being shown in FIG.  3 . The glide support in the preferred embodiment of the present invention is connected to the support ends  52  and  54  of the first connecting rail  16  and the second connecting rail  18 , respectively. Each glide support  72  is further configured to be guided within the trough  56  for slidably guiding the support ends in the trough. 
     FIG. 4 depicts a perspective view of a preferred embodiment of a glide support  72  according to the present invention. As seen in FIG. 4, each glide support  72  includes an extended base portion  74  having side edges  76 , and a narrowed head portion  78  defining a hole  80  therein for each guide pin  64 . The glide support further preferably defines curved recesses  81  on each side thereof at a central region of its base portion for accommodating a pivoting motion of a corresponding end of a connecting rail. Thus, as readily recognizable by one skilled in the art, and as seen in FIG. 3, each connecting rail is connected to its corresponding glide support  72  by being fastened thereto by way of guide pin  64  extending through hole  80  (FIG. 4) of the glide support. Each glide support rests within the trough  56 , its side edges  76  substantially abutting the inner surfaces of sidewalls  58  of support rail  12 . Thus, each glide support  72  is slidably guided within trough  56 , in turn slidably guiding each support end of each connecting rail with respect to the support rail. 
     Referring now to FIGS. 5 a  through  5   c , connecting parts for connecting the support end of each connecting rail to its glide support and to the support rail are shown. As seen in FIG. 5 a , a cross section of the portion of each support end  52 ,  54  of each connecting rail  16 ,  18  connected to the support rail  12  is shown in a plane transverse to the longitudinal direction of the support rail. Pin  64  extends through the slots  68  in the support rail, through corresponding holes  84  in the support end  52 / 54 , and through hole  80  in each glide support  72  as shown. Each pin  64  is held in position by a pair of locking rings  86 . 
     Referring now to FIG. 5 b , a side view of a preferred embodiment of a guide pin  64  is shown. The guide pin preferably has a body portion  88  adapted to extend within trough  56  of support rail  12 , and end portions  90 . Guide pin  64  defines recesses  92  between each end portion  90  and the body portion  88  for accommodating a respective locking ring  86  (FIG. 5 c ) therein. As seen in FIG. 5 c , the locking ring  86  is preferably substantially annular, and defines an opening  94  adapted to be snapped onto a corresponding recess  92  of the guide pin  64 . The above arrangement ensures a secure slidable guiding connection between each connecting rail and the support rail. Preferably, a lubricant (not shown) is disposed in the trough for lubricating a sliding motion of each glide support within the trough. The lubricant may be disposed on top surface  60  of the support rail  12 , at the underside of each glide support, and preferably along top surface  60  along the entire sliding path of each glide support. 
     As seen in FIGS. 1 through 3, the presser assembly according to the present invention preferably includes a rubber pad  96  fixed to a lower surface of the presser rail  14  for frictionally engaging a scrap thereunder during the blanking operation. Preferably, the presser rail further defines two pairs of facing recesses  100  therein. As best seen in FIG. 2, each pair of the two pairs of recesses includes a first recess  100  in one sidewall  48  of the presser rail and a second recess  100  in another, facing sidewall  48  of the presser rail  14 , the recesses of each pair being in registration in a direction transverse to a longitudinal direction of the presser rail  14 . As seen in FIG. 1, the recesses of each pair are preferably spaced from one another such that, in a fully folded state of the presser assembly, the support rail  12 , the connecting rail and the presser rail are substantially parallel to one another, and the first guide pin  64  and the second guide pin  64  are each received in a respective one of the two pairs of recesses  100  for allowing the presser assembly to fold fully with the presser rail  14  fitting almost fully within the groove  56  of support rail  12 . 
     As shown in FIGS. 1 through 3, the preferred embodiment of the presser assembly according to the present invention includes two assembly flanges  110 , one flange on each end of the support rail  12 . As seen in FIG. 2, each flange includes one or more through holes  112  therein for allowing a fastening of the presser assembly to a male blanker board. 
     Optionally, a pair of resting pads  98 , as seen in FIG. 1, are provided on bottom wall  50  of the presser rail, each of the pads  98  being disposed at a respective one of the first end  20  and the second end  21  of the presser rail such that, in a default mode of the first connecting rail and the second connecting rail as shown in FIG. 1, a tip of the presser end of each of the first connecting rail and the second connecting rail rests against a corresponding one of the resting pads. The resting pads advantageously prevent a scratching of the bottom wall  50  of the presser rail  14  by the tip of the presser ends of the connecting rails  16  and  18 . 
     Preferably, according to the present invention, at least the support rail, presser rail, and connecting rails are made of steel or aluminum, and are die punched for rigidity. The glide supports are in turn preferably made of a hard, durable plastic, preferably a slidable plastic such as polytetrafluoroethylene or another fluoropolymer. 
     As can be appreciated from the figures, the connecting rails are configured for effecting a folding of the presser assembly such that, in a fully folded state of the presser assembly, the support rail, the connecting rail and the presser rail are substantially parallel to one another. Advantageously, the invention provides a presser assembly that is easy to install on male blanker boards and that, by virtue of its simple construction, is easily manufactured, is generally less costly to manufacture than presser assemblies of the prior art, and is removed from male blanker boards of blanking devices with ease for being changed or reused. Furthermore, the presser assembly according to the present invention maintains the advantages of prior art presser assemblies, such as the ability to adjust to unequal pressure on the assembly, while substantially eliminating a possibility that the assembly will jam, as happens with presser assemblies of the prior art using guide cylinders. Additionally, the presser assembly according to a preferred embodiment of the present invention, unlike the presser assemblies of the prior art, does not require height adjustment, and thus can be much more efficiently mounted onto male blanker boards. Typically, the presser assembly according to a preferred embodiment of the present invention may be mounted in two to three minutes, while the presser assemblies of the prior art typically require adjustment of assembly lasting from two to three hours. 
     The present invention further includes a kit for forming a presser assembly for supporting blanking scrap during a blanking operation. The kit according to the present invention includes: a support rail, such as support rail  12 ; a presser rail, such as presser rail  14  adapted to be connected to the support rail; and a connecting rail adapted to connect the presser rail to the support rail and adapted to pivot with respect to at least one of the support rail and the presser rail in an assembled state of the presser assembly through a predetermined pivot angle range for changing a distance between the support rail and the presser rail. A reduction of the distance between the support rail and the presser rail, such as of the distance D shown in FIG. 1, effects a folding of the presser assembly during the blanking operation. The kit according to the present invention encompasses the components of the presser assembly adapted to be connected to one another for forming the presser assembly. Thus, the kit includes, in a preferred embodiment of the present invention, the first connecting rail  16  and the second connecting rail  18  adapted to connect the presser rail  14  to the support rail  12 , respectively, at the first end  20  and at the second end  21  thereof. The kit according to the preferred embodiment of the present invention further includes the biasing mechanism  26 , which in turn includes the torsion spring  32 . 
     In operation, as readily recognizable by one skilled in the art, the support rail  12  may be pushed toward the presser rail  14  for pivoting the connecting rails  16  and  18  with respect to at least one of the support rail and the presser rail for reducing angle α thereby folding the presser assembly for reducing a distance between the presser rail and the support rail. For unfolding the presser assembly, the method according to the present invention includes the step of pivoting the connecting rails  16  and  18  with respect to at least one of the support rail and the presser rail for increasing angle α defined therebetween, thereby unfolding the presser assembly for increasing a distance between the presser rail and the support rail. For achieving a fully folded state of the presser assembly, the method according to the present invention includes the step of pivoting the connecting rail for achieving a fully folded state of the presser assembly wherein the support rail, the connecting rail and the presser rail are substantially parallel with respect to one another, and preferably such that the presser rail almost fully rests within a groove of the support rail. 
     The present invention further includes within its scope a presser assembly for supporting blanking scrap during a blanking operation, the presser assembly including: a support means; a presser means connected to the support means and supported thereby; and a connecting means for connecting the presser rail to the support rail and being adapted to pivot with respect to the presser rail through a predetermined pivot angle range for changing a distance between the presser rail and the support rail thereby selectively effecting a folding and an unfolding of the presser assembly during the blanking operation. The means mentioned above are substantially shown and described in relation to FIGS. 1 through 6. 
     It will be apparent to those skilled in the art that the disclosed invention may be modified in numerous ways and may assume many embodiments other than the preferred forms specifically set out and described above. Accordingly, it is intended by the appended claims to cover all modifications of the invention that fall within the true spirit and scope of the invention.