Abstract:
An envelope closing mechanism with a deflector ( 11; 61 ) for urging a flap ( 6 ) of an envelope ( 3 ) from the transport path ( 20; 70 ); and a moistener ( 7 ) for moistening at least a portion of the flap ( 6 ) of an envelope ( 3 ). The deflector ( 11; 61 ) is movable between a position of rest on a side of the transport path ( 20; 70 ) located opposite the moistener, and a deflecting position on the other side of the transport path ( 20; 70 ) for urging the flap ( 6 ) of the envelope ( 3 ) against the moistener ( 7 ). If the deflector ( 11, 61 ) is in the deflecting position, it releases the transport path ( 20; 70 ) for transporting the envelope ( 3 ) along the deflector ( 11, 61 ). From a position in which the flap ( 6 ) of the envelope ( 3 ) extends between the moistener ( 7 ) and the deflector ( 11 ) in a deflecting position, the envelope ( 3 ), following the transport path ( 20; 70 ) is transported along the deflector ( 11 ) in the deflecting position with the fold leading. A method for closing envelopes is also described.

Description:
FIELD AND BACKGROUND OF THE INVENTION  
       [0001]     The invention relates to an envelope closing mechanism and to a method for closing an envelope.  
         [0002]     Envelope closing mechanisms are used for closing envelopes in a mechanized manner and are, in practice, often also designed for filling the envelopes, in which case such devices are designated, in practice, as inserters.  
         [0003]     From European patent application 0 100 674, an envelope closing mechanism and a method are known in which the envelope is supplied with the flap leading, and urged from the path by the deflector, against a water wheel located below the path, which wets the flap until the relatively rigid envelope body filled with content urges the freely movable deflector away from the water wheel again. Moreover, the flap contacts a flap guide also located below the transport path and downstream of the water wheel, thereby folding the flap to a closed position.  
         [0004]     A drawback of this known envelope closing mechanism is that the construction is relatively complex and that, especially at high processing speed and with soft envelopes, it is difficult to prevent moisture from the water wheel and glue dissolved therein coming from previously wetted envelopes, from ending up on the body and the content of the envelope.  
       SUMMARY OF THE INVENTION  
       [0005]     It is an object of the invention to provide a solution that enables moistening and closing the flaps of envelopes by means of a simple construction, while staining the body and the content of the envelope with moisture and glue is prevented in a reliable manner.  
         [0006]     According to the present invention, this object is achieved by providing an envelope closing mechanism, comprising:  
         [0007]     a guide for guiding an envelope in a transport path;  
         [0008]     a transport structure for moving the envelope in at least one transport direction along the transport path;  
         [0009]     a deflector for urging a flap of an envelope connected along a fold to an envelope body of the envelope from the transport path; and  
         [0010]     a moistener for moistening at least a portion of the flap of an envelope at a position on a first side of the transport path and at a distance from the transport path;  
         [0011]     wherein the deflector is movable between a position of rest on a second side of the transport path located opposite the moistener, and a deflecting position on said first side of the transport path for urging at least a portion of the flap of the envelope against the moistener, in which deflecting position the deflector is free from the transport path for allowing the envelope to pass the deflector during transport along the transport path; and  
         [0012]     wherein the transport structure is controllable for transporting the envelope from a position in which the flap of the envelope extends between the moistener and the deflector in the deflecting position, with said fold leading and following the transport path along the deflector in the deflecting position.  
         [0013]     The invention can also be embodied in a method for closing an envelope having an envelope body for accommodating a content, and a flap connected along a fold to the envelope body, from a position in which the envelope body and the flap extend in transport direction of a transport path, comprising:  
         [0014]     pivoting the flap out of the transport path by a deflector into a position in which the flap of the envelope extends between a moistener and the deflector in the deflecting position; and  
         [0015]     transporting the envelope along the transport path with the fold leading and following the transport path along the deflector in the deflecting position, while the flap moves along the moistener and pivots to a position against the envelope body.  
         [0016]     As upon transport, the envelope is fed with the fold leading and following the transport path along the deflector in the deflecting position, other parts of the envelope and the content remain at a relatively large distance from the moistener, and the deflector needs not be urged from the deflecting position by the envelope body. The deflector in the deflecting position keeps the envelope body away from the moistener so that the risk of staining the envelope body and the content is considerably reduced.  
         [0017]     An additional advantage is that as, upon closing, the flap travels around the deflector, one single deflector can suffice for urging the flap of the envelope towards the deflector and to the closed position.  
         [0018]     Design aspects of the invention are laid down in the dependent claims and appear from the following description of exemplary embodiments represented in the drawings, in which also further effects and design details of the invention are laid down. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0019]      FIGS. 1-4  are schematized perspective representations of an example of an envelope closing mechanism according to the invention in successive operative conditions which occur during a cycle of an example of a method according to the invention, and  
         [0020]      FIG. 5  is a schematic perspective representation of an alternative exemplary embodiment of an envelope closing mechanism according to the invention. 
     
    
     DETAILED DESCRIPTION  
       [0021]     The envelope closing mechanism  1  according to the example shown in  FIGS. 1-4  is equipped with a guide  2  for guiding an envelope  3  in a transport path  20 . The envelopes to be closed are of the type having an envelope body  4  for accommodating a content, and a flap  6  connected via a fold  5  to one of two walls of the envelope body  4 . Here, the fold  5  proceeding along the flap  6  forms a hinge about which the flap  6 , upon closing, hinges relative to the envelope body  4 . Such an envelope  3  is represented in  FIG. 1 . It lies flat in the transport path  20  while a side of the flap  6 , provided locally with glue, is in open position facing downward.  
         [0022]     A pair of roller presses  16 ,  17 , of which presses one is drivable, form a transporting structure for moving the envelope  3  along the transport path  20 .  
         [0023]     At a first side of the transport path  20  (according to this example, the underside, but the construction can also, in principle, be placed upside down or at an inclination, in which case the upper side, a lateral side or an upward or downward facing side of the transport path forms the first side) a moistener  7  is situated for moistening the flap  6 . According to this example, the moistener  7  is equipped with a moistening cushion  21 , a liquid reservoir  8  and a liquid pump  9  for pumping the liquid in a dosed manner to the moistening cushion  21 , and is located at some distance from the transport path  20 . Due to the dosed supply of liquid, sufficient moistening with a limited risk of spilling can be realized.  
         [0024]     With the envelope closing mechanism  1  in the position of rest, the moistener  7  is shielded from the envelope  3  by a hinged panel  10 , thereby preventing uncontrolled moistening of the flap  6  or other parts of the envelope  3 . According to this example, this panel  10  is urged to its shielding position through spring force, so that it is designed to be self-closing in a simple manner.  
         [0025]     In a position of rest (see  FIG. 1 ), a deflector  11 , movable between two positions, is situated on a side of the transport path  20  opposite the moistener  7 , according to this example, the top side. Via two arms  22 , 23 , the deflector  11  is pivotally suspended about an axis  24  (see  FIG. 1 ). In the so-called deflecting position (see  FIGS. 2-4 ), the deflector  11  is located at the same side of the transport path as the moistener  7 .  
         [0026]     According to this example, the deflector  11  is designed as a row of discs, axially spaced, coaxially and rotatably suspended about a rotation axis  25  (see  FIGS. 1 and 2 ). The rotation axis  25  is directed parallel to the plane of the transport path  20  defined by the guide  2 , and moves with the deflector  11  upon displacement thereof between the position of rest and the deflecting position. It is noted that within the framework of the invention, also other designs of the suspension and the construction and shape of the deflector  11  are possible.  
         [0027]     In operation, through suitable control of the drive of the roller presses  16 ,  17 , an envelope  3  is brought to a position in which the fold  5  between the body  4  and the flap  6  of the envelope  3  is located approximately opposite the deflector  11 . To this end, means known per se can be used, such as a transport control as described in U.S. Pat. No. 5,899,050. The envelope  3  can for instance be fed in a direction as represented with an arrow  26  in  FIG. 1 , in other words, with the flap leading and reaching the deflector  11  from a side thereof where the roller presses  16 ,  17  are located.  
         [0028]     By then moving the deflector  11  in the direction indicated with arrow  12  in  FIG. 2  from the position of rest to the deflecting position, the deflector  11  urges both the panel  10  to its releasing position and the flap  6  from the transport path against the moistener  7  which, initially, was shielded by the panel  10 . The contact between the flap  6  and the moistener  7  can be effected by pushing the flap  6  in a nip between the deflector  11  and the moistener  7  against the moistener  7 , or conversely, by bending the flap  6  towards the moistener  7  in such a manner that a part of the flap  6  projecting from the deflector is pushed against the moistener  7  without a nip between the moistener  7  and the deflector  11  being involved. This latter is preferred because this further limits the risk of moisture being transferred by the deflector  11  from the moistener  7  onto the envelope  3  or a subsequent envelope and thus staining the envelope with moisture and glue dissolved therein coming from the previously moistened envelopes.  
         [0029]     Then, as represented with arrow  13  in  FIG. 3 , the envelope is moved with the fold  5  leading, along the transport path  20 , whereby the leading fold  5  displaces the parts of the envelops  3  contiguous thereto, following the transport path  20 , along the deflector  11  which is in deflecting position. Here, the flap  6  is pulled from between the moistener  7  and the deflector  11 , is moistened, and runs approximately from the leading fold  5  down over the deflector  11  to a closed position. Here, running the flap  6  gradually over the deflector  11  is promoted in that the deflector comprises a roller which is rotatable about the rotation axis  25  parallel to a plane in which envelopes  3  extend in the path  20 .  
         [0030]     As the parts  4  of the envelope which are not to be moistened pass the deflector  11  only at a distance from the part of the deflector  11  located opposite the moistener  7 , the risk of staining the parts  4  of the envelope  3  which should not be moistened is reduced. Further, due to friction between the flap  6  and the moistener  7 , the flap  6  is held tightly around the deflector  11  so that staining of the mechanism in the area of the moistener  7  is prevented.  
         [0031]     With a mechanism according to the example shown, staining the envelope is further prevented in that the moistener  7  is situated on a side of the deflector  11  remote from the transport path  20  if the deflector is in the deflecting position. Thus, the deflector  11  moreover forms a shield between the transport path  20  and the moistener  7 , thereby further reducing the risk of staining an envelope or the content thereof.  
         [0032]     Further, for preventing direct contact between parts  4  of the envelope  3  that are not to be moistened and the moistener  7 , it is not required that the deflector  11  moves from its deflecting position. Closing the flap  6  can therefore, after moistening, be carried out very rapidly without a highly accurately timed control of movements of the deflector  11  being required, or movements of the deflector  11  driven by the body  4  of the envelope  3  being required, which can hardly be reliably ensured, especially with relatively soft envelopes.  
         [0033]     As, the deflector  11  is of elongated design in cross direction of the transport path  20 , it can, upon closing, urge the flap  6  of the envelope  3  in a bend with a small radius, so that reliable pressing against the moistener situated at the outside of this bend can be guaranteed in a simple manner.  
         [0034]     After closing the flap  6  of the envelope  3 , the envelope  3  is led in opposite direction (arrow  14  in  FIG. 4 ) through a closing nip  15  between the roller presses  16 ,  17 , for pressing-on the folded-up flap  6 . Thus, a good adhesion of the surface of flap  6 , locally moistened and provided with glue, and parts of the envelope body  4  abutting against it is promoted. With the exemplary embodiment shown in  FIGS. 1-4 , the closing nip  15  is formed by the roller presses  16 ,  17  located on either side of the transport path.  
         [0035]     As the envelope  3 , when fed with the flap leading, and discharged after closing of the flap  6  in a direction opposite the feed direction  26 , is always held between the roller presses  16 ,  17 , no separate driven transport means are required, but the same rollers can be used for transporting the envelope  3  and for pressing-on the closed flap  6 .  
         [0036]     It is noted that various embodiments are possible such as, for instance, instead of two mutually opposed roller presses, one roller press combined with a circulating or not circulating press-on surface. Further, the closing nip  15  can also, viewed in feed direction, be placed downstream of the deflector  11 . This latter offers the advantage that the envelope can be closed without reversing the transport direction, which is advantageous for increasing the capacity of the mechanism.  
         [0037]      FIG. 5  shows an alternative exemplary embodiment of an envelope closing mechanism  51 , wherein the deflector  61  at the same time forms a roller press for pressing-on the folded-up flap. To this end, the deflector  61  is designed as a roller  67  and a second roller press is provided in such a manner that this is located on a side of the transport path  70  opposite the first roller press  61  when the deflector  61  is in its deflecting position. This second roller press  66  is connected to the deflector  61  such that in the deflecting position, they together form a closing nip  65  situated in the transport path  70 .