FR2523509A1 - CIRCULAR MACHINE FOR THE AUTOMATIC MANUFACTURE OF PRESENTATION BOXES - Google Patents

Abstract

The machine for making display containers which are made from folded cardboard and plastics material, has a circular table which is rotated about a vertical axis to align with six working stations spaced equal distances apart around its edge. Also spaced equal distances apart around the table are six suction boxes which are extended and retracted to convey the cardboard and plastics elements between the working positions. The working stations receive the elements from storage positions, where they are removed from a stack and folding operations are carried out, followed by adhesive application and assembly, using high frequency heating for the adhesive coated parts. Pref. the adhesive used is an aq. dispersion of polyacrylic ester or a polyvinyl acetate copolymer.

Description

 The present invention relates to a device for assembling cardboard and plastic cutouts, in particular for producing presentation boxes of the type comprising an opening overlapping at least one edge and which is closed by a sheet of rigid plastic material. transparent with notches at the ends of its fold lines. Such presentation boxes and their manufacturing process are already described in French patent No. 80 26 305 of 11.12.1980 and its certificate of addition No. 81 13 025 of 02.07.1981 in the name of the present applicant.

 In said main patent, a method and a device are described in which a cardboard blank, previously coated with an adhesive material, is placed on it; a pre-cleaned plastic cutout. The implementation of this technique has proved difficult and expensive. In fact, it requires extremely precise positioning or wedging of the plastic blank in relation to the blank or the cardboard blank.

 Said certificate of addition proposes an assembly process according to which the grooving of the plastic cutout is carried out after the sealing of the cutout on the cardboard surface. This grooving can also be carried out at the same time as the sealing of the plastic cutout and preferably by a high frequency press.

 The object of the present invention is to design an automatic device for implementing the last said process according to said invention certificate.

 The device according to the present invention comprises a horizontal circular plate movable around a vertical axis, a series of suction boxes mounted on said plate, connected to a vacuum source and intended to receive the cutouts to be assembled, a series of work stations arranged around said plate in predetermined angular positions and which comprise at least: a station for feeding the cardboard blanks, a station for feeding the plastic blanks, a control station to check the presence of the blanks on the suction boxes, a station for sealing HF plastic cutouts on cardboard cutouts, a receiving station to collect the cutouts assembled from the boxes and control means ensuring intermittent angular displacement of the tray to bring the boxes from one of the workstations to the other and to activate each of these stations after each angular movement of the plate u.

 Thanks to this arrangement, the cardboard cutout is first placed on a suction box. Then this box is advanced to the feeding station of the plastic cutouts. The plastic cutout is placed on the cardboard and held in position by the suction of the box being made through the cutout window (s). At the same time, another cardboard blank is placed on the next box.

 During subsequent operations, in particular the grooving and sealing of the plastic cutout, the positioning of the latter with respect to the cardboard is perfectly maintained and no other wedging is necessary. In addition, thanks to the arrangement of the boxes on a circular plate, a space-saving device is obtained which operates continuously without empty movement of return of the boxes.

 In addition, according to the invention, each of the blank feed stations and said reception station comprises a frame disposed radially with respect to said plate and which extends partially above the latter, a plate mounted movable in vertical direction on said frame and which is intended to receive said separate or assembled cutouts, a frame mounted movable on radial rails provided at the upper end of said frame and which can be brought from a first radial position, in which it extends above said tray in a second radial position, in which it extends above a suction box of said tray, a series of suction cups mounted on crosspieces of said movable frame and which are connected to a source of vacuum, means control allowing to bring said frame or said crosspieces in a low position for gripping and depositing the blanks and in a high position for the translational movement of said frame from one e of these said positions in the other.

 These positions have a relatively simple and very reliable structure. The removal and deposit of the blanks by the suction cups mounted on a mobile frame allows precise positioning of the blanks on the suction boxes. Such a feeding station is in particular intended for the manipulation of cardboard plans comprising a whole series of windows for the simultaneous assembly of several boxes which are then cut or separated from each other as described in the cited addition certificate. above.

 The supply of individual plastic cutouts requires greater precision.

 To this end, the plastic blanks feeding station comprises, according to a preferred embodiment of the invention, a removable guide plate intended to be placed on said movable plate and which supports a series of vertical guides between which are arranged. , on movable boards, in vertical direction, said cutouts, the section and arrangement of said guides being such that the cutouts are guided along their notches, a fixed plate situated above said mobile plate and below said mobile frame carrying the suction cups and which carries on the underside a series of fixed guides whose section and arrangement correspond to those of said vertical guides, the fixed plate having between the guides a series of openings for the passage of the blanks during their removal by the suction cups.

 This gives very precise guidance and positioning of the cuts. This guidance system is of a simple structure and can easily be modified according to the dimensions and configurations of the cuts to be fed.

 To avoid the simultaneous removal of several cuts from a stack, said fixed guides according to the invention comprise in the vicinity of their upper ends and on their guide surface a series of openings or perforations connected to a source of compressed air.

 Such a feeding station can also be used when it is desired to simultaneously deposit several individual cardboard blanks each forming a single box. In this case, the guides extend into the corners of the cutout windows.

 According to a particularly advantageous embodiment of the device according to the invention, said sealing and / or grooving station comprises a high-frequency press having a fixed jaw disposed below said plate and a movable jaw disposed above this plate, said suction boxes being supported relative to the plate by bearings cooperating with vertical rods provided on the plate and which include elastic return means tending to maintain the boxes at a predetermined distance above the plate, the plate comprising opposite the body of each box, an opening so that the latter can be brought under the action of the movable jaw of the press, through this opening, in contact with the fixed jaw and this against the action of said elastic return means.

 Preferably said bearings and said rods have internal cylindrical parts between which is engaged a deformable elastic seal and conical end upper parts cooperating directly with each other when the box extends in its high position and which are released one of the other when the box is brought by the movable jaw against the action of the return means in its low position.

 Thanks to this structure, the expansion of the boxes is compensated for by the heat released by the HF press. In addition, it is ensured that the boxes are brought into perfect parallelism between the two jaws of the press.

 For sealing and grooving of plastic cutouts, two separate HF presses can also be provided, placed on two successive workstations.

 In addition to avoid disturbance of the automatic control means, device according to the invention, by magnetic fields produced by the operation of the press and to electrically separate the press and the control means from the circular plate, the starting of the station press is controlled via an opto-electronic barrier.

Said press comprises two drawers between a source of compressed air and two presostats inserted in the control circuit, means for driving said plate, said drawers being brought into their open positions by contacts actuated by the movable jaw when it extends in its high position.

 Finally, to avoid damage to the press and the boxes, when one of the boxes is accidentally in an abnormal vertical position, said plate comprises between each pair of boxes, a cam cooperating with a fixed contactor inserted in the control circuit of the press and whose actuation by the cam results in a loosening and a displacement in the high position of the movable jaw of the press.

Other embodiments and advantages of the invention will emerge from the description which follows and with reference to the accompanying drawings, showing by way of example a preferred embodiment of the device according to the invention in these drawings. FIG. 1 is a schematic plan view of the entire device according to
the invention, FIG. 2 is a very schematic plan view of the supply stations and
receiving plans or cardboard cutouts, Figure 3 is a partial side elevational view showing in more detail
the reception station which is very similar to the food station
tion of cardboard plans, Figure 4 is a partial front and side elevational view of the station
feeding the plastic blanks, Figure 5 is a perspective view of the station guides, shown in
Figure 4, Figure 6 is an elevational view of the suction cup control
different positions shown in Figures 2 to 4, Figure 7 is a plan view with partial cutaway of a suction box
of the turntable of the device shown in Figure 1, Figure 8 is a sectional view along line VIII - VIII of Figure 6, Figure 9 is a sectional view along line IX --IX of Figure 7, Figure 10 is a schematic sectional view of the sealing station and / or
HF grooving, figure It shows the control of the circular plate, figure 12 schematically shows the start control of the HF press.

 The device according to the invention shown in Figure 1 essentially comprises a horizontal circular plate 1 which is rotated by a known motor and transmission. These means ensure intermittent movement of the plate 1 over a predetermined angular distance corresponding to the distance between two neighboring work stations, placed opposite the plate.

 In the embodiment shown here, the device comprises six work stations arranged around the plate 1 and which are spaced from each other by a predetermined angular distance. These work stations include a station for feeding the cardboard blanks 2, a station for feeding the plastic blanks 3, a counter post for the 4, a sealing station 5, a second control station 6 and a receiving station 7 for removing assembled cuts.

 On the tray 1 are mounted opposite the work stations, six suction boxes 8, 9, 10, 11, 12 and 13, one of which is shown in detail in Figures 6 to 8. Each box is connected by a flexible conduit 14 and through an inlet valve 15 and a discharge valve 16 to a central vacuum generator 17 not shown in detail here. Between the conduits 14 and the generator 17 are provided, in a known manner, rotary joints 18. The control of valves 15 and 16 will be described later, during the explanation of the operation of the device according to the invention.

 Each of the work stations 2, 3 and 7 has a general structure as shown very diagrammatically in FIG. 2. A part of the reception station 7 and a part of the station for feeding the plastic blanks 3 are shown in more detail. in Figures 3 and 4, 5 respectively.

 Each station 2, 3 and 7 has outside of the plate 1, a frame consisting of vertical uprights 19, 20 carrying horizontal rails 21, 22 whose spacing corresponds substantially to the length of the suction boxes 8 to 13. The rails 21, 22 extend above the plate 1 to the inner end of the suction boxes. On the rails 21, 22 is mounted a movable frame 23 comprising crosspieces 24 on which suction cups are provided 25. The frame 23 can be advanced into a position in which it is located above a suction box, for example 13 as shown in Figure 3 and be removed in a second position in which it is outside the tray. In the outer part of the tray 1 of the frame 19, 20, is provided a feed or receiving tray removable 26 which can be moved in the vertical direction and which is controlled by a chain drive device not shown. In Figure 3, we only see an attachment point 27 for fixing a chain of this device. At the level of the plate 26, the frame 19, 20 and the rails 21, 22 are arranged with known feeders constituted for example by adjustable abutment elements 28, 29.

 The suction cups 25 are connected by flexible pipes to a vacuum source not shown here. Known control means are provided for connecting or cutting the suction cups 25 of this vacuum source. The frame 23 carrying the crosspieces 24 with the suction cups 25 is actuated by a double-acting cylinder 30 shown in FIG. 3.

 In addition, the frame 23 and the suction cups 25 can be lowered and raised to take up or deposit a cutout of cardboard or plastic. The means controlling these movements are shown in more detail in FIG. 6. In this figure, there is seen a suction cup 25 mounted on a cross-member 24 which is connected in the vicinity of these ends to vertical rods 31, 32 extending upwards. through a tubular guide 33, 34 fixed to the frame. At its upper end, each rod 31, 32 comprises a wider head 35, 36 serving as a stop for a helical spring 37 engaged on the rod between this head and the upper end of the guide 33, 34.

This spring 37 thus tends to hold the rod 31 and thus the suction cup 25 in its upper position (as shown on the right side). To control the lowering of the suction cups, a jack 38 is provided on the frame, the rod 39 of which is connected by its free end to the free end of a double lever 40. This lever 40 is fixed on a pivot 41 on which is also wedged a lever 42. The other end of the lever 42 is disposed above the rod 32. Above the rod 31, extends the free end of another lever 43 wedged on a pivot 44 On the latter, a lever 45 is also wedged, the free end of which is connected by an articulated rod 46 to the other free end of the lever 40.

 When the jack 38 is actuated, its rod 39 pivots the lever 40 in the opposite direction to the clockwise direction. The levers 42 and 43 are lowered and push the rods 31, 32 against the action of the spring 37 downwards. The suction cups 25 are thus lowered on the blanks to be removed or deposited on a suction box of the tray 1.

 The structure of the supply station 3 for the plastic blanks 55 'is slightly different from the stations 2 and 7 and in particular comprises means for the precise guiding of the blanks as shown in FIGS. 4 and 5.

 The device for feeding the plastic blanks comprises suction and translating means with suction cups similar to those of the device for feeding the cardboard blanks 2 and the receiving station 7 as shown in FIGS. 2, 3 and 6 and already described above. For reasons of clarity, these means are not shown in FIG. 4.

 The station shown in FIG. 4 comprises a reception plate 46 corresponding to the plate 26 of stations 2 and 7. The plate 46 is mounted adjustable in lateral direction thanks to a manual adjustment assembly comprising a floating angle gear 50 fixed on the underside of the plate 46 and which cooperates with an endless screw 51 which can be actuated by a handwheel 52.

 The plate 46 is intended to support a guide-carrying plate 3 on which are fixed several vertical guides 54 between which the plastic cutouts 55 ′ are arranged as shown in FIG. 5. These cutouts 55 ′ have notches 56 at the level of the ends of their fold lines 57. These indentations 56 have a substantially frustoconical configuration and the guides 54 are arranged on the plate 53 so as to be engaged in these indentations 56 and have for this purpose a section matching the shape of the latter. The neighboring guides 54 are held in their intermediate parts by spacer rods 58. Each guide 54 has at its lower end a wider base 59 allowing its fixing by screws 60 on the plate 53. This assembly is particularly simple and allows to quickly modify the arrangement of the guides 54 on the plate 53 according to the dimensions and the configuration of the cutouts 55 ′.

 To facilitate the guiding of the blanks 551 arranged in the form of superimposed piles between the guides 54, the parts of the latter engaged in the notches 56 are slightly flared in the lower parts of the guides. This prevents blockage of the cutouts between the guides when they are moved upwards. To control this movement, the blanks 55 'rest on boards 61 extending between the guides 54 and which are supported by control plates 62 mounted movable in the vertical direction. The movement of these plates 63 is controlled by chain transmissions which, in FIG. 4, show a chain 63 fixed to the plate 6, 2. This chain is driven by a pinion 64 wedged on the shaft of a motor of command 65.

 Above the movable guides 54, a set of fixed guides 66 is provided, supported by a plate 67 connected by arms 68 to the frame of the station for feeding the plastic cutouts. The guides 66 are aligned with the guides 54 and the plate 67 has openings 69 for the passage of the cutouts 55 '. To avoid sticking of the upper 55 extreme cutouts on the stack of cutouts resting on the boards 61, the fixed guides 66 have at their upper ends openings through which compressed air is sent as indicated in 70. This arrangement ensures that the suction cups of this station take at each work cycle only one cutout 55 per stack.

 The structure of the different suction boxes 9 to 13 of the circular plate 1 is shown in detail in Figures 6, 7 and 8. Each box consists of a rectangular element or box divided by vertical walls 71 into a series of compartments 72 communicating between them and connected as shown in Figure 1, by the flexible conduits 14 and the valves 15 to the vacuum source. 17. The upper face of each box is closed by a sheet 73 having a multitude of perforations 74 ensuring the suction of the cardboard and plastic cutouts 55 '.

The boxes are fixed to the plate 1 by bearings 75 to 78. The bearings 75 and 76 have a large clearance while the bearing 77 has a limited clearance. The structure of the bearings 75, 76 and 77 is represented in FIG. 9 while the structure of the bearing 78 which is different, is represented in FIG. 8. The particular structure of these bearings has proved to be necessary for the passage of the boxes 8 to 13 under the sealing press and the hot grooving by HF radiation of station 5. Indeed, at this station the boxes are subjected in the HF press (figure 9), to a heating producing an expansion of the material composing the structure boxes, especially aluminum, this expansion is large enough to jeopardize the positioning of the boxes and their vertical movement and thereby the cardboard and plastic cutouts, relative to the sealing and / or grooving tools to hot press
HF. These tools are not shown and described here because they correspond to the tools described in detail in the French patent and the certificate of addition of the applicant already cited above.

 To compensate for this expansion and thus ensure high-precision sealing and / or grooving, the boxes must be mounted movable in a horizontal plane and along two axes. Furthermore, to equalize the pressure over the entire surface of each box between the fixed jaw 89 and the movable jaw 90 of the HF press (FIG. 9), the boxes must be mounted movable in a vertical direction relative to the circular plate 1.

 Each bearing 75 to 78 comprises, on a tab 79 provided at the four angles of the box, a vertical passage 80 in which is arranged a sheath 81 carrying an elastic joint 82. the sheath 81 has a cylindrical lower interior part 83 and an upper upper part conical 84. Between the vertical parts of the sheath 81 and the tab 79 is provided a free space or limited clearance. Through the passage 80, the sheath 81 and the joint 82 extends a vertical rod 85 fixed to the plate 1. This rod also has a lower cylindrical part 86 and an upper conical upper part 87. Between the plate 1 and the box is disposed on the rod 85, a helical spring 88 tending to keep the box 9 at a predetermined distance above the plate 1. In this upper position, the conical part 87 of the rod 85 cooperates with the conical part 84 of the sheath 81 and the box is immobilized and locks in a predetermined centered position. It is kept in this position when it is opposite work stations 2, 3, 4, 6 and 7.

 On the other hand, when the box is brought between the fixed jaw 89 and the movable jaw 90 of the sealing and grooving press HF 91 (FIG. 9) of station 5 and the press is actuated, the movable jaw 90 clamps the box 9 ', against the action of the springs 88 on the fixed jaw 89 as described below. At this moment the conical part 87 of the rod 85 is released from the conical part 81 of the sheath 80. It then establishes a certain clearance between the box and the rods 85, that is to say, relative to the plate 1.

The box 9 can thus be brought into perfect parallelism with the jaws 89, 90 of the press 91. This is essential for achieving a good sealing and / or grooving of the plastic cutout 55 ′ because these operations depend on the intensity applied to the press, the pressure exerted on the cutouts 55 and 55 'between the two jaws 89, 90 and the clamping time of the jaws of the press.

 The bearing 78 (Figures 7 and 8) has substantially the same structure as the bearings 75 to 77. But in this case, no play is provided between the sheath 81 and the lug 79. In addition the head of the rod has a polygonal section as shown in figure 7.

 To avoid damage to the press 91, the plate (1) comprises, between each pair of boxes, a fixed cam (FIG. 10) cooperating with a fixed contactor 94 which is inserted in the control circuit of the press.

The contactor 94 can only be actuated in the indexing position and will authorize the descent of the press. When there occurs, during the descent of the movable jaw of the press, an accidental shift of the plate, the movable jaw is automatically returned to its high rest position.

 To avoid interactions between the electrical circuits of the press 91 and the control means of the plate 1, the starting of these two elements is controlled by the hydraulic and optical means respectively.

 FIG. 11 schematically shows the control of the clutch 102 of the plate 1. On the press are provided two drawers 95, 96 connected to a source of compressed air 97 which include contacts 103, 104 actuated by the movable jaw 90 when it s 'extends in its high position. The drawers 95, 94 then actuate two presostats 98, 99 one of which applies a supply current 110 to a shaping circuit 101. The start signal supplied by this circuit is applied by the other presostat 99 to l 'clutch 112 of the plate 1. The latter can thus only advance when the movable jaw of the press extends in its high position.

 The press is started up through an optoelectric barrier (Figure 12) comprising a current source 105 supplying a projector 106 has at one end a light guide 107. At the other end of this guide, is arranged a photoelectric cell 108 supplying through an amplifier 109, the current for the start circuit 110 of the press.

 Of course, the invention is not limited to the embodiments described and shown here, but many modifications can be made without departing from the scope of the invention.

Claims (9)

 1. Device for assembling cardboard and plastic blanks, in particular for making presentation boxes of the type comprising an opening overlapping at least one edge and which is closed by a sheet (55) of plastic rigid transparent having at the ends of its fold lines (57) notches (56), characterized in that it comprises: a) a horizontal circular plate (1) movable around a vertical axis, a series of suction boxes ( 8 to 13) mounted on said plate (1), connected to a vacuum source (17) and intended to receive the blanks (55, 55 ') to be assembled, b) a series of work stations (2 to 7) arranged around said plate (1) in predetermined angular positions and which include at least one station (2) for feeding the cardboard blanks (55 '), a station (3) for feeding the plastic blanks (55 ), a control station (4) to check the presence of the cutouts (55, 55 ') on the es suction boxes (8 to 13), a station (5) for sealing and / or grooving HF plastic cutouts (55) on cardboard cutouts (55 '), a receiving station (7) for take the assembled blanks (55, 55 ') from the boxes (8 to 13) c) control means ensuring an intermittent angular displacement of the plate (1) to bring the boxes (8 to 13) from one of the stations of work (2 to 7) to the other and to activate each of these stations after each angular displacement of the plate (1).  2. Device according to claim 1, characterized in that each of the feed stations (2, 3) of the blanks (55, 55 ') and said reception station (7) comprises a frame (19, 20) arranged radially by relative to said plate (1) and which extends partially above the latter, a plate (26, 46) mounted movable in vertical direction on said frame (19, 20) and which is intended to receive said separate or assembled cutouts , a frame (23) movably mounted on radial rails (21, 22) provided at the upper end of said frame (19, 20) and which can be brought from a first radial position, in which it extends above said plate (26, 46), in a second radial position, in which it extends above a suction box (8 to 13) of said plate (1), a series of suction cups (25) mounted on crosspieces (24) of said movable frame (23) and which are connected to a vacuum source, control means (38 to 46) making it possible to bring said frame (23) or lesdi your crosspieces (24) in a low position for gripping and depositing the cutouts (55, 55 ') and in a high position for the translational movement of said frame (23) from one of its said positions in the other .  3. Device according to claim 2, characterized in that said feeding station (3) of the plastic cutouts (55) further comprises a removable guide-carrying plate (53) intended to be placed on said movable plate (46 ) and which supports a series of vertical guides (54) between which are arranged, on movable boards (61), in vertical direction, said cutouts, the section and arrangement of said guides (54) being such that the cutouts (55) are guided along their notches (56), a fixed plate (67) located above said movable plate (46) and below said movable frame carrying the suction cups (25) and which carries on the underside a series of guides fixed (66) whose section and arrangement correspond to those of said vertical guides (54), the fixed plate (67) having between the guides (66) a series of openings (69) for the passage of the cutouts (55) during of their removal by the suction cups (25).  4. Device according to claim 3, characterized in that said fixed guides (66) comprise in the vicinity of their upper ends and on their guide surface a series of openings or perforations (70) connected to a source of compressed air.  5. Device according to any one of claims 1 to 4, charac terized in that said sealing and / or grooving station (5) comprises a high frequency press (91) having a fixed jaw (89) disposed below said plate (1) and a movable jaw (90) disposed above this plate (1), said suction boxes (8 to 13) being supported relative to the plate (1) by bearings (75 to 78) cooperating with vertical rods (85) provided on the plate (1) and which comprise elastic return means (88) tending to maintain the boxes at a predetermined distance above the plate (1), the plate (1) comprising opposite of the body of each box (8 to 13), an opening (92) so that the latter can be brought under the action of the movable jaw (90) of the press (91), through this opening, in contact with the fixed jaw (89) and this against the action of said elastic return means (88).  6. Device according to claim 5 characterized in that said bearings (75 to 78 and said rods (85) have internal cylindrical parts (83, 86) between which is engaged a deformable elastic seal (82) and upper conical upper parts (84, 87) cooperating directly with each other when the box extends in its high position and which are released from one another when the box is brought by the movable jaw (90) against the action of the return means (88) in its low position.  7. Device according to any one of claims 5 or 6, charac terized in that the starting of the press (91) of the station (5) is controlled by means of an opto-electronic barrier (105 to 109).  8. Device according to any one of claims 5 to 7, charac terized in that said press (91) comprises two drawers (95, 96) between a source of compressed air (97) and two presostats (98, 99) inserted into the control circuit (100 to 102), means for driving said plate (1), said drawers (95, 96) being brought into their open positions by contacts (103, 104) actuated by the jaw mobile (90) when it extends in its high position.  9. Device according to any one of claims 5 to 8 characterized in that said plate (1) comprises between each pair of boxes (8 to 13) a cam (93) cooperating with a fixed contactor (94) inserted in the circuit control press (91) and whose actuation by the czme (93) results in a loosening and a displacement in the high position of the movable jaw (90) of the press (91).