EP0542341A1

EP0542341A1 - Device for closing the side flaps of boxes with fold-down flaps

Info

Publication number: EP0542341A1
Application number: EP92203372A
Authority: EP
Inventors: Augusto Marchetti
Original assignee: Individual
Current assignee: Individual
Priority date: 1991-11-11
Filing date: 1992-11-04
Publication date: 1993-05-19
Also published as: ITMI912997A0; IT1252001B; JPH05220872A; ITMI912997A1

Abstract

The device comprises a pair of symmetrical plates (11) normally elastically kept in respective substantially vertical planes convergent in the direction of advancement of the boxes and suitable for rotating on respective convergent oblique axes under the action of the front edge of boxes of variable width until the side flaps (24, 25) of the boxes are closed.

Description

The present invention relates to a device for closing the side flaps of boxes with fold-down flaps.
Machines are known capable of executing in rapid succession the closing of the end flaps and then of the side flaps of a cardboard box before the application of an adhesive sealing tape along the space separating the side flaps folded down in the closed position.
For the closing of the side flaps, according to the European patent No. 194711 of the same Applicant, a device is known and used formed by a pair of helix-shaped convergent symmetrical guides, that coming up against the side flaps cause their progressive displacement to the closed position.
Each guide comprises two integral helix-shaped portions, one more external and one more internal with respect to the axis of symmetry. The two helix-shaped portions are staggered one with respect to the other and each of them extends from substantially parallel oblique inlet extremities to complanar horizontal outlet extremities, so as to be engageable by the upright side flaps of boxes of greater and lesser width, respectively, to progressively fold the flaps themselves to the closed position.
Accomplished in this way, the device for closing the side flaps does not require any distance adjustment in relation to the width of the boxes, offering the more external portion of the helix to the initial engagement with the side flaps of the wider boxes and the more internal portion of the helix to the initial engagement with the side flaps of the narrower boxes.
Naturally the particular shape with which they are manufactured makes the accomplishment of such guides very complicated and ill-suited for a low-cost industrial production.
The object of the present invention is to accomplish a device for closing the side flaps of boxes with fold-down flaps, that attains the same result of not requiring any adjustment in relation to the width of the boxes, while at the same time being of simpler construction and suitable for a financially advantageous industrial production.
According to the invention such object is attained through a device for closing the side flaps of boxes with fold-down flaps, characterized in that it comprises a pair of symmetrical flat plates normally elastically kept in respective substantially vertical planes convergent in the direction of advancement of the boxes and suitable for rotating on respective correspondingly convergent oblique axes under the action of the front edges of boxes of variable width until at least their portions brought reciprocally close to one another are moved to respective complanar horizontal positions for closing the side flaps of the boxes.
It appears evident that, given the flat shape and the convergent vertical arrangement of the two plates and their ability to rotate on respective convergent oblique axes, whatever the width of the arriving box the side flaps of the box are capable of coming up against said plates to be consequently induced to rotate towards the closing position, which they reach in a definitive manner when the front edges of the box in turn come up against the plates, causing their rotation to the final position at least partially horizontal.
The desired result is thus attained with the help of means, such as the two plates, with an extremely simple and inexpensive construction.
The features of the present invention shall be made more evident by an embodiment illustrated as a non-limiting example in the enclosed drawings, wherein:

Fig. 1 shows a plan view from above, with parts removed, of a machine for closing cardboard boxes that includes a device for closing the upper side flaps according to the present invention, said device being shown in the at rest position, just before its intervention on a box in the closing step;
Fig. 2 shows the same closing machine in a partially-sectioned side view;
Fig. 3 shows the same closing machine in a front view from the box-inlet extremity;
Fig. 4 shows a plan view from above of the enlarged detail of one of the rotatable plates that constitute the device for closing the side flaps that is shown in the previous figures;
Fig. 5 is a sectional view taken along the line V-V of Fig. 4;
Fig. 6 shows the same plate in a side view;
Fig. 7 shows the same plate in a front view;
Fig. 8 shows a plan view from above of the closing machine in an initial step of the operation for closing the upper side flaps of a box;
Fig. 9 shows a front view of the closing machine in said initial step;
Fig. 10 shows a plan view from above of the closing machine in a subsequent step of the operation for closing the side flaps of the box;
Fig. 11 shows a front view of the closing machine in said subsequent step;
Fig. 12 shows a plan view from above of the closing machine at the end of the operation for closing the side flaps of the box;
Fig. 13 shows a side view of the closing machine in the final position of Fig. 12;
Fig. 14 shows a front view of the closing machine in the final position of Fig.s 12 and 13.

The machine shown in the drawings comprises a plane for supporting and advancing boxes 19 in the closing step, defined by a succession of idle rollers 1 supported by a base frame 2. Along the two sides of the supporting plane there are two belt-operated driving units 3, that through known means which can be operated by a handle 4 can be placed at an adjustable reciprocal distance from one another such as to allow their engagement with the sides 22, 23 of the boxes for the advancement of the latter (from right to left looking at Fig. 1).
Two lateral uprights 5 support in a vertically adjustable manner (through known means which can be operated by a handle 6) a portal-shaped structure 7 including a beam 8. From the latter there extend toward the box-inlet extremity (to the right in Fig.s 1 and 2) means of support (not shown and known in themselves) for a device for closing the upper end flaps of the boxes, also not shown and known in itself. In combination with this device there operates a device for keeping the end flaps in the closed position, also known in itself and not shown.
The closing of the upper side flaps of the boxes is entrusted to a device according to the invention, whose details are illustrated in Fig.s 4-7.
It consists of a pair of substantially plane plates 11 fastened to rotation pins 12 with oblique axes converging downward and in the direction of advancement of the boxes.
Each pin 12 is rotatably mounted in a protection housing 13 made integral with a support 14 fastened to and overhanging the beam 8.
The extremities of each pin 12 are inserted and fastened with bolts 40 in holes 15 obtained in plates 16, 17 protruding from the rear surface of the plates 11.
Between each support 14 and the corresponding plate 11 there is interposed a reaction spring 18, which normally keeps the plate in a substantially vertical plane (defined by a limit switch 41), that converges toward that of the other plate 11 in the direction of the advancement of the boxes (Fig.s 1-3).
As a result of the structure described above the device operates as follows.
At rest, as already said, both the plates 11 are urged in a vertical position by the reaction springs 18.
A box 19 positioned on the idle rollers 1 is made to advance by the belt-operated driving units 3, so as to engage their front and rear flaps 20 and 21 first with the device for closing the end flaps and then with the device for keeping the same in a closed position, neither of them shown.
The distance of the belt-operated driving units 3 may be adjusted by means of the handle 4 so that through the engagement with the sides 22, 23 of the box the advancement of the latter is ensured in the direction indicated by the arrow in Fig. 1.
Proceeding along the supporting plane with the end flaps already closed but with the side flaps 24 and 25 still open and outwardly diverging (Fig.s 1 and 3), the engagement of the latter with the plates 11 determines the progressive rotation of the same side flaps toward the vertical position, aligned with the sides 22, 23, that is shown in Fig.s 8 and 9.
When the box reaches the position illustrated in Fig. 8, the upper front edges of the box engage the lower edges of the plates 11 and, with the further advancement of the box, cause the progressive rotation of the plates 11 on their pins 12 and the consequent further closing rotation of the side flaps 24 and 25 (Fig.s 10 and 11).
At the end of their rotation, the plates 11 reach the final position of Fig.s 12-14, wherein their portions brought reciprocally close to one another 31 are in complanar horizontal positions, so as to complete the folding down of the side flaps 24, 25.
It is easy to see that the manner of operation of this device is absolutely independent of the width of the box, whose side flaps 24, 25 in any case come up against the plates 11 and are obliged by these to fold over in the closing position.

Claims

Device for closing the side flaps of boxes with fold-down flaps, characterized in that it comprises a pair of symmetrical flat plates (11) normally elastically kept in respective substantially vertical planes convergent in the direction of advancement of the boxes (19) and suitable for rotating on respective correspondingly convergent oblique axes (12) under the action of the front edges of boxes of variable width until at least their portions brought reciprocally close to one another (31) are moved to respective complanar horizontal positions for closing the side flaps (24, 25) of the boxes.
Device according to claim 1, characterised in that each of said plates (11) is rotatably hinged on a respective support (14) fastened to and overhanging a beam (8) that can be adjusted in height with respect to a plane for supporting and advancing the boxes.
Device according to claim 1, characterized in that it comprises means (41) suitable for defining said substantially vertical planes for the plates (11) in the at rest position.