SYSTEM FOR WOODEN BOX BOTTOM STITCHING

The invention refers to a system whose purpose is stitching the bottom of a wooden or com pressed paperboard box to the frame body of the box, where such items are used as main parts of wooden or compressed paperboard box production machines. This requires two main mechanisms: the stitching head and the "riveter", i.e. a mechanism compressing and causing plastic deformation of the wire upon the items to be stitched, so as to avoid protru sion of wire edges. The items to be stitched are the bottom and the frame of a wooden box. Furthermore, the "riveter" applies resistive force on the wood and allows it to be perforated by the wire being driven on it; at the same time, the wire is secured and cannot be displaced. This design operates at a faster rate, produces less operating noise, compared to designs currently available, and the outcome is far more reliable. In earlier boxes, the stapled wire was poorly fit; this led to loosening of the fastening location and box failure. This design results in stronger, tighter stitching; therefore, the box is more durable.

The invention refers to stitching the bottom to the remaining frame body of wooden or com pressed paperboard boxes. The two main mechanisms required are the stitching head and the "riveter" mechanism; this initially retains the wooden pieces and applies resistive force on them; in this way, they remain fixed during stitching and can be perforated by the wire. Then, the "riveter" compresses and causes plastic deformation of the wire upon the items to be stitched.

Such machine designs are not widely used, due to the specific characteristics of the end product. Compared to earlier designs, this one generates less noise; at the same time, it is quicker and ensures a more reliable finish. The point of fixing (stapling) on boxes is much stronger; this provides end products with improved quality and durability.

The invention is illustrated in detailed figures. Figure 1 shows, in side view, the position of the stitching head in relation to the "riveter" mechanism. Figure 2 shows a stand-alone riveter with its individual components. Figure 3 shows an exploded view of the stitching head subsystem. Figure 4 shows a front view and a section view of the stitching head with the cap removed.

The stitching head is mounted on the plate (5) is connected on part (4), by the pin (3) and part (2) on the shaft (1). The latter transmits drive to the former. The shaft (1), part of a group of driving mechanisms, follows an elliptical orbit. Part (4) is coupled to part (29), and the latter is screwed on plate (30). Plate (30) supports the articulated attachment of parts (31) & (32); these are designated as “staplers” by the manufacturer, thanks to their ability to staple the wire on the wood. Drive is transmitted to plates (37) & (38) through parts (33) & (34) which are joined with pins (35) & (36) respectively. These in turn, are embedded in the mount of the head (28). In detail, parts (39) follow the contoured guiding shapes of the grooves made on the plates (30), (37) & (38), thus ensuring their synchronized motion and achieving the required effect. Wire is fed through part (40) at a specific position, while plates are returning to their original position, before the stitching movement has started. Part (41) is used to retain and guide the wire. The manufacturer refers to part (42) as the "former", due to its purpose of forming the wire into the shape of a "P", so that the wire can follow its path and obtain its final shape through parts (43), (44) & (45). Parts (45) & (42) are under con stant pressure applied by the plates (46) & (47) respectively, to develop the force to allow their rebound to the initial position. The manufacturer refers to part (48) as the "cutter" since its purpose is wire cutting. The "cutter" (48) is coupled to plate (38) through part (49). In particular, at the start of travel, all three plates (30), (37) & (38) including their auxiliary parts, travel concurrently until part (50) located on plate (37) reaches its final position and stops; this position is the point of contact with the vertical sides of the box to be stitched. As soon as plate (37) stops its travel, plates (30) & (38) keep moving. While plate (38) fitted with cutter (48) is in motion, wire is cut and pre-formed in a “P” pattern, using the “former” (42). Plate (30) keeps moving and the "staplers" start to guide the wire through the grooves of parts (43) and (44) to provide the final form of the wire; in a last step, the wire is stapled onto the wooden work pieces. The "riveter" is connected to the arm (6) that rotates around a shaft (8). The movement of the arm (6) is transmitted by the same group of driving mecha nisms that also drives the stitching head. The arm (6) is linked to the above-mentioned driv ing group through the pin (7) and this method delimits its range of movement. During the stitching process part (50) of the stitching head first comes into contact with the walls of the wooden pieces; then the "riveter" is lowered, so that part (25) applies pressure on the walls of the wooden pieces and retains them to allow stitching to be done. As soon as part (25) forces the wooden pieces and the stitching is completed, at the same time a pneumatic valve is actuated and the air piston (9) expands; in this way, the tensioned tension spring (16) forcefully returns to its initial length, forcing part (24) to move forcefully and rapidly and compress and deform the edges of the wire; thus the latter are driven in the mass of the wood without protruding. The tension spring (16) is used to accelerate the return stroke of the pis ton during expansion, so that part (24) is synchronized with the stitching speed applied by the stitching head. Part (24) slides inside a suitably shaped part, therefore moving to a specif ic direction, avoiding random motion. In addition, part (24) is connected to part (12) through the pins (23), (21) and also through part (22). Parts (13) & (27) slide in oval shaped grooves, so that part (12) travels vertically. The shaft (19) is fixed and carries part (20) on it. Part (20) slides inside the specially shaped groove of part (12) as the latter moves by the force of the piston (9), thus avoiding free rotation of part (12). The piston (9) is linked to pin (26) by ar ticulated joint, and is connected to (12) through the pin (11) and the part (10). The bottom end of the spring (16) is connected to part (17) which, in turn, is linked on the pin (18), whereas the top end is connected to part (14), and the latter in turn is linked to (12) through the pin (15).