Patent Publication Number: US-6698742-B2

Title: Apparatus for applying supplementary products to printed products

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to an apparatus which is intended for supplying supplementary products to printed products and pressing them onto the latter and has the features of the preambles of patent claims  1  and  10 . 
     An apparatus of this type is known from EP Patent Application No. 00122324.7 (Publication No. EP-A-1 112 861). It has circulatory elements which are provided, on the one hand, with a suction element and, on the other hand, with a supporting element and are each mounted rotatably on carrying levers which, for their part, are articulated, such that they are distributed uniformly in the circumferential direction, on a carrying disk which is driven in rotation about its axis. The rotary position of the circulatory elements and the pivoting position of the carrying levers are controlled by means of a control arrangement. At a pick-up location, the suction element of each circulatory element picks up in each case one supplementary product and leads it to a press-on location, where it is applied to one side of a printed product, of which the other side is supported by means of the supporting element of an adjacent circulatory element. Depending on the side of the printed products to which the supplementary products are to be adhesively bonded, the circulatory elements are rotated to one side or the other by means of the control arrangement, for which purpose conversion of the apparatus is necessary in each case. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to develop the known apparatus such that the task of changing over the application of supplementary products from one side of the printed products to the other can take place easily and quickly. 
     The object is achieved by an apparatus of the generic type which has the features in the characterizing parts of claims  1  and  10 . 
     The apparatus according to the invention makes it possible for the supplementary products to be optionally transferred from one circulatory element to an adjacent one. 
     A particularly preferred embodiment of the apparatus according to the invention is specified in claims  2  and  13 . By virtue of a control section of the control arrangement being switched over, it is possible to change over from the supplementary products being applied to one side of the printed products to the other side, which can take place very quickly and virtually without any outlay being required. 
     Further preferred embodiments of the apparatus according to the invention are specified in the further claims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will be explained in more detail with reference to exemplary embodiments illustrated in the drawing, in which, purely schematically: 
     FIG. 1 shows a view, partly in section, of an apparatus according to the invention in a first mode of operation, a supply arrangement for supplying the supplementary products to the apparatus, and a conveying arrangement for transporting, in a hanging state, printed products onto which the supplementary products are pressed by means of the apparatus; 
     FIG. 2 shows, in the same illustration as in FIG. 1, the apparatus from the latter in a second mode of operation, in which the supplementary products are transferred to the preceding circulatory element in each case in order to be pressed onto the printed products on the other side; 
     FIG. 3 shows a side view of part of the apparatus shown in FIGS. 1 and 2, with two circulatory elements, the leading one already having picked up a supplementary product; 
     FIG. 4 shows a schematic view of the pneumatic state of the circulatory element which is shown in FIG.  3  and has not yet picked up a supplementary product; 
     FIG. 5 shows, schematically, the pneumatic state of the circulatory element according to FIG. 3 which has already picked up a supplementary product; 
     FIG. 6 shows, in the same view as in FIG. 3, two adjacent circulatory elements during transfer of a supplementary product from one circulatory element to the preceding circulatory element; 
     FIG. 7 shows, schematically, the pneumatic state of the two circulatory elements shown in FIG. 6; 
     FIG. 8 shows, in the same illustration as in FIG. 6, the two circulatory elements from the latter as the supplementary product received by the leading circulatory element is pressed onto a printed product; 
     FIG. 9 shows, schematically, the pneumatic state of the two circulatory elements shown in FIG. 8; 
     FIG. 10 shows, as in FIG. 3, the two circulatory elements from the latter respectively with and without a supplementary product; 
     FIG. 11 shows, schematically, corresponding to FIG. 4, the pneumatic state of the circulatory element which does not retain a supplementary product in FIG. 10; 
     FIG. 12 shows, schematically, corresponding to FIG. 5, the pneumatic state of the circulatory element which retains a supplementary product in FIG. 10; 
     FIG. 13 shows, corresponding to FIG. 6, two circulatory elements in a second mode of operation of the apparatus according to the invention, in which no transfer of the supplementary products from one circulatory element to the other takes place; 
     FIG. 14 shows, schematically, the pneumatic state of the two circulatory elements shown in FIG. 13; 
     FIG. 15 shows, corresponding to FIG. 8, the two circulatory elements from FIG. 13 as the supplementary product retained by the trailing circulatory element is pressed onto a printed product; 
     FIG. 16 shows, schematically, corresponding to FIG. 9, the pneumatic state of the circulatory elements according to FIG. 15; 
     FIG. 17 shows a side view, partly in section, of a circulatory element with an ejector installed and the cutouts for accommodating suction elements with integrated suction valve and an air-admission valve; 
     FIG. 18 shows a section along line XVIII—XVIII from FIG.  17  through the circulatory element with the air-admission valve installed; 
     FIG. 19 shows a section along line XIX—XIX according to FIG.  17  through the circulatory element with the suction elements and integrated suction valves; 
     FIG. 20 shows a view of part of the apparatus according to the invention in an embodiment in which the circulatory elements are directed forward, as seen in the direction of circulation, for the purpose of picking up a supplementary product; 
     FIG. 21 shows, corresponding to FIG. 6 but on an enlarged scale, two adjacent circulatory elements—constructed differently from FIGS. 3 to  19 —during transfer of a supplementary product from one circulatory element to the preceding circulatory element; and 
     FIG. 22 shows, schematically, the pneumatic state of the two circulatory elements shown in FIG.  21 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The apparatus  10  shown in FIGS. 1 and 2 has a number of circulatory elements  12 , which are moved in a direction of circulation U along a more or less circular circulatory path  14  and are arranged one behind the other. The circulatory elements  12 , which are of identical design, have a cross section similar to an isosceles trapezoid, the base of this cross section being arranged in a rotationally fixed manner on a shaft  20  in each case. Each of these shafts  20  is mounted in a freely rotatable manner at the free end of a first leg  22  of a carrying lever  26 , which is designed as an angled lever and, for its part, is articulated on a carrying disk  28 . The carrying disk  28  is driven continuously about its axis of rotation  30  in the direction of circulation U, the points of articulation of the carrying levers  26  being located on a circular line around the axis of rotation  30  and being distributed uniformly in the circumferential direction. Mounted in a freely rotatable manner on the second legs  24  of the carrying levers  26  are control rollers  32 , which interact with a stationary pivoting guide  34  of a pivoting control means  36 , said pivoting guide running around the axis of rotation. The pivoting control means  36  is assigned a switch-over element  40  which forms a control section  38  and can be changed over in the radially inward direction, in relation to the axis of rotation  30 , from a rest position, which is shown in FIG. 1, into a transfer position  44 . As can be gathered from FIG. 1, in the rest position  42  of the switch-over element  40 , the control section  38  is located outside the pivoting guide  34 , as seen in the radial direction, as a result of which a concave section of the pivoting guide  34  in a transfer region  45  of the circulatory path  14  is bridged and the control rollers  32  in this section interact with the control section  38  and are lifted off from the stationary pivoting guide  34 . In the transfer position  44 , however, as FIG. 2 shows, the control section  38  is located within the stationary pivoting guide  34 , as seen in the radial direction, with the result that the control rollers  32  interact with the pivoting guide  34  along the entire extent of the same. 
     Mounted in a freely rotatable manner on the carrying disk  28 , on the articulation pins  46  of the carrying levers  26 , are coupling wheels which are drive-connected on the one hand, via a first drive belt  48 , to the shafts  20 , which bear the circulatory elements  12 , and on the other hand, via a second drive belt  50 , to control wheels  52 , which are mounted on the carrying disk  28 . Each of the control wheels  52  is fixedly connected to a control lever  54  which, at its free end, bears a control roller  56  which is mounted in a freely rotatable manner. The control rollers  56  interact with a stationary rotary guide  58 . The rotary position of the circulatory elements  12  is controlled in a location-dependent manner by said rotary control means  60 . The pivoting control means  36  and the rotary control means  60  together form a control arrangement  61  for the circulatory elements  12 . 
     Two spaced-apart carrying disks  28  are advantageously seated on a drive shaft  30 ′, which is coaxial with the axis of rotation  30 , mutually associated carrying levers  26  in each case which are connected to one another via a shaft  20 , which bears a circulatory element  12 , being articulated on said carrying disks, as is disclosed, in particular, in FIG. 6 of EP-A-1 112 861. The pivoting guide  34  and rotary guide  58  are likewise preferably formed on two fixed plates, on which the drive shaft  30 ′ is mounted and which are located outside the carrying disks  28 , as seen in the direction of the axis of rotation  30 , this likewise being disclosed in EP-A-1 112 861.The switch-over element  40  is preferably arranged on the abovementioned plates, the rotary guide  58 , which is otherwise formed as a groove-like depression of constant cross section in the plates, having a greater width in the region of the control section  38 . 
     Each circulatory element  12  has a suction element  62  and a supporting element  64  in each case on a first side  16  and on a second side  18 —which, in cross section, form the legs of the isosceles trapezoid. This will be described in more detail hereinbelow in conjunction with FIGS. 3 to  19 . 
     Leading past above the apparatus  10  is a conveying arrangement  66 , of which the transporting clamps  68 , which are spaced apart one behind the other, are driven in a conveying direction F, synchronously with the apparatus  10 . Each transporting clamp  68  secures a printed product  70 —which may be a printed product with one or more sheets—and transports the same, in a hanging position, in the horizontal direction beyond the apparatus  10 , although a top section of the circulatory path  14  of the circulatory elements  12  is located in the movement region of the printed products  70 . Located at the top point of the circulatory path  14  is a press-on location  71 , in which, as is yet to be described, supplementary products  72  are pressed onto the printed products  70  by means of the circulatory elements  12 . 
     The supplementary products  72  are fed individually, by means of a supply arrangement  74 , to a pick-up location  76 , where they are received, in order to be transported further, by the circulatory elements  12  moving past the pick-up location  76 . The supply arrangement  74 , as is known, may be of different designs; in the present case it has a supply wheel  78 . 
     The supplementary products  72  may be so-called Post-it® notes, which are provided with adhesive  80  in a strip-like region. However, they may also constitute other types of supplementary products  72  which, by means of the apparatus  10 , are fed to the printed products  70  and pressed onto the latter in order for the supplementary products  72  to be adhesively bonded to the printed products  70 . 
     The transfer region  45  and thus the switch-over element  40  with the control section  38  are located between the pick-up location  76  and the press-on location  71 , in which case they are arranged downstream of the pick-up location  76  and upstream of the press-on location  71 , as seen in the direction of circulation U. 
     FIGS. 3,  6 ,  8 ,  10 ,  13  and  15  each show a region of the carrying disk  28 , which is driven continuously in rotation in the direction of circulation U, with two carrying levers  26 , which are articulated on the carrying disk and each bear a circulatory element  12 , at different points in time of an operating cycle. That position of the carrying levers  26  and circulatory elements  12  which is shown in these figures corresponds to that which they also assume at the relevant point in time in FIGS. 1 and 2. The same parts are provided with the same designations as in FIGS. 1 and 2. 
     For better understanding of the functioning of the circulatory elements  12 , and of FIGS. 4,  5 ,  7 ,  9 ,  11 ,  12 ,  14  and  16 , which schematically illustrate the respective pneumatic state, the construction of the circulatory elements  12  will be described, for the time being, with reference to FIGS. 17 to  19 . 
     Each of the circulatory elements  12  has a circulatory body  82  with a cross section in the form of an isosceles trapezoid, from which a fastening flange  84  projects on the side of the base of the cross section. From a fastening hole  86  in the fastening flange  84 , a slot  88  runs to the free end of the fastening flange  84 . This slot  88  can be narrowed by means of a screw, in order for the circulatory body  82  to be fastened in the desired rotary position on the shaft  20 , which is guided through the fastening hole  86 . Fastened in a flatly abutting manner against the outer surfaces of the circulatory body  82 , said surfaces being arranged at an acute angle in relation to one another, are rectangular plates  90  which, on the side which is directed away from the fastening flange  84 , project beyond the circulatory body  82  and are bent round toward one another, in order to butt against one another in the manner of a wedge at the free end. 
     Running through the circulatory body  82 , parallel to the fastening hole  86 , is a cutout  92 , in which a generally known ejector  94  is installed. As is indicated by the arrow  96 , this ejector is supplied with compressed air, in order to serve as a negative-pressure source  94 ′. The negative-pressure outlet of the ejector  94  is connected by means of bores in the circulatory body  82 , on the one hand, to an accommodating opening  98 , which is assigned to the second side  18  and is intended for a suction element  62 , and, on the other hand, to a blind-hole-like accommodating opening  100  for an air-admission valve  102 . The air-admission valve  102  is connected, by means of further bores, to a further accommodating opening  98  for the suction element  62  assigned to the first side  16 . 
     The accommodating openings  98  run at right angles to the plate  90  and the relevant side of the circulatory body  82 . Inserted into each of these accommodating openings  98  is a suction head  104 , which is retained by the plates  90  in the manner of a groove/wedge connection and has a plate-rim-like sealing lip  104 ′ at the outer, free end. An actuating shaft  106  engages through the central through-passage of the suction head  104 , leaving an annular gap in the process, a cup-like valve body  108  being integrally formed at the inner end of said actuating shaft. The annular shoulder of the valve body  108 , which adjoins the actuating shaft  106 , interacts, as a sealing surface, with a valve seat which is formed by the inner end side of the suction head  104 . Located in the interior of the valve body  108  is a compression spring  110 , which forces the valve body  108  against the suction head  104  in the closed position. In this closed position, the actuating shaft  106  has its free end projecting beyond the suction head  104 . The valve body  108  along with the actuating shaft  106  and the suction head  104  together form a self-closing suction valve  112  which, with the actuating shaft  106  forced inward, connects the suction head  104  to the negative-pressure source  94 ′ and/or the air-admission valve  102 . The compression spring  110  is coordinated with the pressure conditions such that the suction valve  112  is kept in the open position if a supplementary product  72 , for example a paper sheet, is retained by the suction head  104 . 
     A planar supporting element  64  in each case is arranged on the outer side of the plates  90  and around the suction head  104 , this supporting element only being set back slightly in relation to the free end of the sealing lip  104 ′. The suction heads  104  are located approximately in the center of the side surfaces of the circulatory body  82  and of the supporting elements  64 . In the direction of the fastening hole  86 , the air-admission valve  102  is offset toward one end side of the circulatory body  82 , in relation to the suction head  104  arranged on the same side. Inserted into the accommodating opening  100  is an air-admission-valve body  116 , which is likewise of cup-like design and has an actuating pin  118  projecting beyond the associated supporting element  64 . An O-ring  120  engages around said actuating pin and, in the closed position of the air-admission valve  102 , closes off the accommodating opening  100  by butting against the relevant plate  90 . The air-admission-valve body  116  is prestressed into the closed position likewise by means of a compression spring  122 . That annular end side of the air-admission-valve body  116  which is directed away from the actuating pin  118  likewise forms a sealing surface  124 , which, in an air-admission position  125  of the air-admission valve  102 , interacts with an O-ring  126 , which butts against a shoulder of the accommodating opening  100  and forms a further valve seat. Opening out adjacent to the base of the blind-hole-like accommodating opening  100  is the bore which connects the air-admission valve  102  to the negative-pressure source  94 ′. Opening out adjacent to the O-ring  126 , in the vicinity of the O-ring  120 , are the two further bores into the accommodating opening  100 , these being connected to one another and to the suction element  62  with integrated suction valve  112  arranged on the same side  16 . In the closed position of the air-admission valve  102 , this position being shown in FIG. 18, the mouth opening located at the O-ring  126  is free, as a result of which the associated suction head  104  with integrated suction valve  112  is connected to the negative-pressure source  94 ′. If, in contrast, the air-admission-valve body  116 , by virtue of the actuating pin  118  being subjected to force, is displaced into the air-admission position  125 , in abutment against the O-ring  126 , on the one hand the abovementioned connection is interrupted and, on the other hand, the associated suction element  62  has air admitted to it in that the mouth opening located at the O-ring  120  is released by the air-admission-valve body  116 . The suction element  62  with integrated suction valve  112  assigned to the first side  16  is thus connected to the negative-pressure source  94 ′ via the air-admission valve  102 , which is likewise assigned to said side  16 , while the suction element  62  with integrated suction valve  112  assigned to the second side  18  of the circulatory element  12  is always connected to the negative-pressure source  94 ′. 
     The schematic views in FIGS. 4,  5 ,  7 ,  9 ,  11 ,  12 ,  14  and  16  show the pneumatic state of one circulatory element  12 , or of two adjacent interacting circulatory elements  12 , at different points in time of an operating cycle. The schematic views show the ejector  94 , which acts as a negative-pressure source  94 ′, the suction element  62  with integrated suction valve  112  assigned to the first side  16  of the circulatory element  12 , the air-admission valve  102 , which is likewise assigned to this first side  16 , the suction element  62  with likewise integrated suction valve  112  assigned to the second side  18 , and the pneumatic connections, as have been described above in conjunction with FIGS. 17 to  19 . The single hatching denotes negative pressure, and no hatching denotes ambient pressure. Cross-hatching means that the ejector  94  has been subjected to the action of compressed air and thus serves as a negative-pressure source  94 ′. If, however, the relevant rectangle has no hatching, this means that the negative-pressure source  94 ′ is inactive, the ejector  94  not being subjected to the action of compressed air. 
     A suitable valve for connecting the ejector  94  to a compressed-air source in dependence on the rotary position, in particular, is a rotary valve, of generally known construction, controlled by the shaft  30 . 
     The apparatus shown in FIGS. 1 to  19  can operate in two different modes, depending on whether the supplementary products  72  are to be applied to a leading side  70 ′ or trailing side  70 ″, as seen in the conveying direction F, of the printed products  70 . For the time being, we will explain the mode of operation in the case of which the supplementary products  72  are to be pressed onto the leading side  70 ′ of the printed products  70 , and which is illustrated in FIG.  2  and in FIGS. 3 to  9 . In this mode of operation, the switch-over element  40  with the control section  38  is located in the transfer position  44  and is thus inactive. 
     The circulatory elements  12 , which are to be fed to the pick-up location  76  one after the other in the direction of circulation U, have been rotated into a position in which they are trailing in relation to the associated carrying lever  26  and are arranged with the free end oriented counter to the direction of circulation U. In this case, the surface of the supporting elements  64  assigned to the outer, first side  16  runs at least more or less tangentially to the circulatory path  14 , as FIG. 3 shows. The first legs  22  of the carrying levers  26  here are retained approximately in the radial direction. 
     It should first be mentioned that, apart from at the press-on location  71 , the ejector  94  is permanently subjected to the action of compressed air. 
     As FIG. 4 shows, in the case of the circulatory elements  12  which are to be fed to the pick-up location  76 , the two suction valves  112  and the air-admission valve  102  are located in the closed position, while the negative-pressure source  94  is activated. Upon reaching the pick-up location  76 , the circulatory element  12  positions itself flatly, by way of the suction head  104  of the suction element  62  assigned to the first side  16 , against the exposed side of a supplementary product  72 , which, retained on the other side by the supply wheel  78 , is fed to the pick-up location  76  at a speed corresponding at least more or less to the speed of circulation of the circulatory element  12  (see FIG.  2 ). In this case, the suction valve  112  assigned to said suction element  62  is opened by the relevant actuating shaft  106  being actuated by the supplementary product  72 . As FIG. 5 shows, said suction valve  112  is kept in the open position since the supplementary product  72  retained by the suction element  62  prevents the valve body  108  from moving back and thus prevents the suction valve  112  from closing. The supplementary product  72  is thus retained by the relevant suction element  62  in order to be transported further. 
     Once they have left the pick-up location  76 , the circulatory elements  12  are pivoted, by means of the rotary control means  60 , into an approximately radially running position, which they assume upon reaching the transfer region  45 . 
     In the transfer region  45 , the pivoting guide  34  and the rotary guide  58  are formed such that the carrying levers  26  are pivoted first of all in the direction of circulation U, and then counter to the direction of circulation U, such that two adjacent circulatory elements  12  position themselves against one another by way of the supporting elements  64 , the second side  18  of the respectively leading circulatory element  12  and the first side  16  of the trailing circulatory element  12  clamping in between them the supplementary product  72  fed by said trailing circulatory element. With this positioning against one another, that supporting element  64  of the leading circulatory element  12  which is assigned to the side  18  actuates the air-admission valve  102  of the trailing circulatory element  12 , as can be seen from FIG. 7 in particular. At the same time, the suction valve  112  assigned to the second side  18  of the leading circulatory element  12  is opened by the supplementary product  72 . This results in the supplementary product  72 , now retained by the relevant suction element  62 , being transported further, while it is released by the suction element  62  assigned to the trailing circulatory element  12  since the relevant suction head  104  has been disconnected from the associated negative-pressure source  94 ′ by means of the air-admission valve  102  and has been connected to the surroundings. 
     The subsequent pivoting of the carrying lever  26  in the direction of circulation U results in the leading circulatory element  12 , which now bears the supplementary product  72 , moving away from the trailing circulatory element  12 , as a result of which the air-admission valve  102  and the associated suction valve  112  of the trailing circulatory element  12  change over again into the closed position. In this way, the supplementary products  72  are discharged in the transfer region  45  from the trailing circulatory element  12  to the respectively preceding circulatory element  12 , the side being changed over at the same time. 
     Downstream of the transfer region  45 , the circulatory elements  12  are rotated such that they have their free end, tapering in a wedge-shaped manner, oriented in the direction of the conveying arrangement  66 , and the carrying levers  26  are controlled such that the circulatory elements  12  mesh with the printed products  70 , which are transported in a hanging state, i.e. in each case one circulatory element  12  is moved in between two adjacent printed products  70 . In other words, a circulatory element  12  is then located on both sides of each printed product  70 , the circulatory elements  12  then bearing the supplementary products  72  on their trailing side  18 , as seen in the direction of circulation U. 
     On approaching the press-on location  71 , the carrying lever  26  assigned to the respectively leading circulatory element  12  is pivoted counter to the direction of circulation U and that carrying lever  26  assigned to the trailing circulatory element  12  is pivoted in the direction of circulation U, which results in the leading circulatory element  12  positioning itself, by way of the supplementary product  72 , on the leading side  70 ′ of the printed product  70  and the trailing element  12  positioning itself, by way of its supporting element  64  assigned to the first side  16 , without any supplementary product, on the trailing side  70 ″ of the printed product. As a result, the supplementary product  72  is pressed onto the printed product  70 , with the result that, if it is provided with an adhesive, it is fastened on the printed product  70 . 
     The carrying levers  26  of the relevant circulatory elements  12  are then pivoted away from one another in order to release the printed product  70  with the supplementary product  72  fastened thereon. As movement continues in the direction of the pick-up location  76 , the circulatory elements  12  and the carrying levers  26  are displaced into the position which is necessary for picking up a new supplementary product  72 . 
     FIGS. 8 and 9 show the situation at the press-on location  71 . The air-admission valve  102 , which is assigned to the leading, first side of the trailing circulatory element  12 , as seen in the direction of circulation U, has been moved out of the closed position into the air-admission position  125  by the opposite supporting element  64  of the leading circulatory element  12  and/or the printed product  70 , as a result of which the associated suction head  104  has air admitted to it. The latter thus cannot secure the printed product  70 . For the purpose of releasing the supplementary product  72 , the compressed-air fed to the ejector  94  of the leading circulatory element  12  is interrupted, as a result of which the negative pressure in the circulatory element  12  is dissipated and the supplementary product  72  can be released. 
     In the case of the mode of operation shown in FIGS. 1 and 10 to  16 , the supplementary products  72  are received individually at the pick-up location  76  in the same way as has been described above in conjunction with the first mode of operation. FIGS. 10,  11  and  12  are thus identical to FIGS. 3,  4  and  5 . Upon reaching the transfer region  45 , each circulatory element  12  bears a supplementary product  72  on its first, front side  16 , as seen in the direction of circulation U. 
     As is shown in FIG. 1, the control section  38  is located in the rest position  42 , as a result of which adjacent,circulatory elements  12  are prevented from moving toward one another until they butt against one another while clamping the relevant supplementary product  72  in between them. In other words, the control section  38 , in the rest position  42 , ensures that the circulatory elements  12 , as they run through the transfer region  45 , are always spaced apart from one another to a sufficient extent, with the result that there is no transfer of the supplementary product  72  from the trailing to the preceding circulatory elements  12 . FIGS. 13 and 14 show these two adjacent and spaced-apart circulatory elements  12  in the transfer region  45 . 
     In that section of the circulatory path  14  which follows the transfer region  45 , as far as the press-on location  71 , the circulatory elements  12  and carrying levers  26  are rotated and/or pivoted in the same way as has been described above in conjunction with the first mode of operation. The circulatory elements  12  then bear the supplementary products  72 , retained on the leading, first side  16 , to the press-on location  71 , which results in supplementary products  72  then being positioned on the trailing side  70 ″ of the printed products  70 , while the printed products  70  are supported on the leading side  70 ′ by the preceding circulatory element  12 . 
     It should be mentioned that, apart from in the region of the control section  38 , irrespective of the mode of operation, the circulatory elements  12  and the carrying levers  26  are rotated and/or controlled in the same manner, with the result that, irrespective of the mode of operation, the position of the circulatory elements  12  is the same everywhere, apart from when they move through the transfer region  45 . 
     FIG. 20 shows an embodiment which is very similar to the above-described embodiment, although in this case, for the purpose of picking up the supplementary products  72  at the pick-up location  76 , the circulatory elements  12  are aligned such that their free, wedge-shaped end is oriented forward, as seen in the direction of circulation U. It is also the case here that the circulatory elements  12  are of the same design as is shown in FIGS. 17 to  19 , although they are fastened the other way round on the shafts, with the result that, in turn, the first side  16  is directed toward the supply arrangement  74  and the second side  18  is directed away from said supply arrangement. Furthermore, the construction and the functioning of the apparatus is the same as has been described above in conjunction with FIGS. 1 to  16 . If the control section  38  is located in the transfer position  44 , the supplementary products  72  are transferred to the trailing circulatory element  12  from the respectively preceding one. 
     FIG. 21 illustrates a further embodiment of the circulatory elements  12 . Here too, each circulatory element  12  has a suction element  62  and a supporting element  64  in each case on the first side  16  and on the second side  18 , which form the legs of the isosceles trapezoid in cross section. 
     FIG. 21 shows a region of the carrying disk  28 , which is driven continuously in rotation in the direction of circulation U, with two carrying levers  76 , which are articulated thereon and each bear a circulatory element  12 , at the same point in time of an operating cycle as FIG.  6 . Equivalent parts are provided with the same designations in FIG. 21 as in FIGS. 1 to  19 . The apparatus according to FIG. 21 is of the same construction, and operates in the same way, as the apparatus according to FIGS. 1 to  19 , with the following exceptions. 
     Installed in the cutout  92  is an ejector  94  which, supplied with compressed air, serves as a negative-pressure source  94 ′, see also FIG.  17 . The negative-pressure outlet of the ejector  94  is connected to the blind-hole-like accommodating opening  100  for the air-admission valve  102  by means of a bore in the circulatory body  82 . Branching off from the abovementioned bore is a smaller-diameter bore—forming a restrictor  128 —which opens out into that accommodating opening  98  for the suction element  62  which is assigned to the second side  18 . The second accommodating opening  98 , for the suction element  62  assigned to the first side  16 , is connected to the air-admission valve  102  by means of a further bore, of which the cross section corresponds approximately to the cross section of the bore leading away from the ejector. The suction elements  62 , however, are not assigned any suction valves  112 , compare with FIG. 19 in particular. 
     The axes of the suction elements  62  and of the air-admission valve  102  are located in a plane which runs at right angles to the shaft  20  and centrally through the circulatory body  82 , the air-admission valve  102  being arranged closer to the shaft  20  than the suction elements  62 . 
     The air-admission-valve body  116 , which is of cup-like design and is inserted into the accommodating opening  100 , has its actuating pin  118  projecting beyond the relevant plate  90  into a cutout of the supporting element  64 . Arranged in said cutout is a leg spring  130 , which is mounted on the supporting element  64  and has one leg interacting with the actuating pin  118  and its other leg projecting beyond the supporting element  64 . The leg spring  130  is designed such that, when the projecting leg is subjected to force, it can displace the air-admission-valve body  116 , counter to the force of the compression spring  122 , from the closed position, which is shown in the leading circulatory element  12 , into the air-admission position, which is illustrated in the trailing circulatory element  12 . 
     In the closed position, the O-ring engaging around the actuating pin  118  closes off the accommodating opening  100  in relation to the surroundings by virtue of butting against the plate  90 . A restrictor through-passage  132  in the air-admission-valve body  116  in this case connects the associated suction element  62  to the negative-pressure source  94 ′. The cross section of the restrictor through-passage  132  corresponds approximately to that of the restrictor  128 . In the air-admission position, the throttle through-passage  132  is closed and separated off from the associated suction element  62 ; the suction element  62  is connected to the surroundings by way of an air gap between the plate  90  and the actuating pin  118  because, as a result, the O-ring is lifted off from the plate  90  and the air gap is connected to the bore leading to the accommodating opening  98 . 
     The transfer of a supplementary product  72  from the front, first side  16  of the trailing circulatory element  12  to the rear, second side  18  of the leading circulatory element  12  will be explained with reference to the schematic view of the pneumatic state from FIG.  22 . The hatching has the same meanings as have been explained above for FIGS. 4,  5 ,  7 ,  9 ,  11 ,  12 ,  14  and  16 . 
     At the pick-up location  76 , see FIG. 2, each circulatory element  12  receives a supplementary product  72  by way of its first side  16 . In this case, the air-admission valve  102  is located in the closed position and the two suction elements  62  are connected to the activated negative-pressure source  94 ′. In the transfer region  45 , the respectively adjacent, approximately radially pivoted circulatory elements  12  are moved toward one another, as a result of which that supporting element  64  of the leading circulatory element  12  which is assigned to the second side  18 , by acting on the projecting leg of the leg spring  130 , changes over the air-admission valve  102  of the trailing circulatory element  12  into the air-admission position. The suction element  62  which has retained the supplementary product  72  up until that point releases the supplementary product  72 , which, at the same time, is attached by suction, by that suction element  62  of the leading circulatory element  12  which is assigned to the second side  18 , and is secured in order to be transported further. 
     At the pick-up location  76 , the supplementary products  72  are preferably received by the circulatory elements  12  such that, during transfer in the transfer region  45 , the relevant supplementary product  72  is clamped in between the supporting element  64  of the leading circulatory element  12  and the leg spring  130  of the trailing circulatory element  12 . The supplementary product  72  is thus retained at all times even if the relevant suction elements  62  are not moved closely enough toward one another for them to come into contact with the supplementary product  72  from both sides at the same time. 
     At the press-on location  71 , see FIG. 2, the supplementary product  72  is released by virtue of the ejector  94  being separated from the compressed-air source. If, however, there is no transfer of the supplementary product  72  in the transfer region, the supplementary product  72  is released by virtue of the air-admission valve  102  being actuated. 
     In the case of the embodiment according to FIGS. 21 and 22, the pneumatic losses are likely to be somewhat greater in comparison with the above-described embodiment, but they are kept within acceptable limits by the restrictor  128  and the restrictor through-passage  132 . The construction of the circulatory elements  12 , however, is simplified considerably, and it is indeed possible to dispense with the suction valves  112 . 
     What has been said above in relation to FIG. 20 also applies analogously to an apparatus with circulatory elements according to FIGS. 21 and 22. 
     It is conceivable for the circulatory elements  12  to be designed in some other manner and, in particular, for the suction and/or air-admission valves  112 ,  102  integrated in the circulatory elements  12  to be actuated, for example, via stationary guides rather than by means of the adjacent circulatory elements  12 . It is also conceivable for the abovementioned valves to be arranged outside the circulatory elements  12 , with the result that the latter are equipped just with the suction elements  62 . In the case of the embodiment with suction valves  112 , it is also possible to dispense with the air-admission valves  102  in the circulatory elements  12 , for example if the suction elements  62  are activated individually. 
     Instead of the carrying disks  28 , it is also possible to use a star wheel. It is also conceivable for the circulatory elements to be guided on a rail.