DESCRIPTION The present Invention relates to an apparatus for the boxing of articles and Is particularly, but not exclusively, concerned with the boxing of substantially laminar articles such as filter bags which are loose or packaged in suitable packets and may contain tea or other infusion products. Throughout the description and the claims, for simplicity and convenience of explanation, use will be made of only the term "article" to mean the loose or packaged filter bag or any other good.

Such type of apparatus is disclosed, for example, in prior art documents EP-A-0 551 613, EP-A-0 250 190 and DE-A-3 708 604. According to the present invention the articles are inserted on edge into respective stalls formed by pairs of equal panels, mutually parallel and equidistant, fixed one following another and transversely on a conveyor belt where there is grouped in the necessary number to accumulate one next to another the quantity of packets which can be contained in a box. The introduction of the articles into said stalls is carried out just before the stalls themselves arrive on the upper horizontal branch of the conveyor belt, when they are still turning around one of the end pulleys of the same conveyor and the pairs of panels which compose the stalls are mutually divergent towards the outside and open in a fan-like manner so that the introduction of the articles into the stalls is greatly facilitated.

When they arrive on the upper, rectilinear branch of the conveyor belt, the pairs of panels which form the stalls are arranged mutually parallel and group the articles which are then inserted contemporaneously and in a known manner, by a pusher and a hopper, into the packaging box placed at the side of the upper group of stalls. During this phase, the articles are guided correctly by the panels of the stalls which contain them singly. To reduce the idle times for packaging of the articles, a special belt conveyor system has been conceived which carries in succession a number of groups of stalls and which comprises at least two endless conveyors arranged side by side which can be actuated independently of one another in order that, while one group of stalls is stationary at the station for boxing the articles, another group of stalls can be actuated for interaction with the feeding conveyor for cyclical feeding of the articles. Major characteristics of the invention and the advantages derived therefrom will appear more clearly from the following description of a preferred embodiment of the same, illustrated only by way of non-limiting example in the figures of the attached drawings, in which:

- Figure 1 is a diagrammatic view in perspective of the apparatus in question;

- Figure 2 is a side view of the initial and intermediate section of the feeding conveyor which feeds the articles in sequence to the conveyor with stalls;

- Figure 3 is a side view of the end section of the feeding conveyor in Figure 2 and of the successive conveyor with stalls;

- Figures 4 and 5 illustrate two constructional details of the positive conveyor for feeding the articles, taken respectively along the section lines IV- IV and V-V of Figures 2 and 3;

- Figure 6 illustrates the conveyor with stalls diagrammatically and from the front side; - Figures 7 and 8 illustrate two details of the conveyor with stalls sectioned respectively along the lines VII-VII and VIII-VIII in Figures 3 and 6.

From Figures 1-2 it can be seen that the articles 1 originating from the production line in single file, correctly orientated and appropriately distanced from one another, are fed by known means into the initial rectilinear and horizontal part 102 of a feeding line comprising a sliding guide 2 which, as illustrated in Figure 4, comprises a longitudinal and median rail 3, on which the articles rest and slide with their median part and comprises "L"-shaped lateral containment profiles 4- 104, on which and against which the longitudinal edges of the same articles 1 rest and slide. The parts 3, 4-104 are fixed on ties 5 mounted in an exact number and in a cantilevered manner on a vertical plate 6 which is integral with a suitable base structure (not illustrated) .

After the initial section 102 (Figure 2), the guide 2 continues upwards with a rectilinear and composite section 202, which will be discussed below,

then with a parabolic section 302 and ends with a rectilinear section 402 which is orientated downwards and appropriately inclined, for example so as to form an angle with the vertical of approximately 35°. The articles 1 are compelled to run longitudinally through the guide 2, in the direction indicated by the arrow 200 (Figure 2) , by forked pushers 7 which interact with portions of the article itself positioned at the side of the rail 3 (Figure 4) and which are fixed mutually equidistantly and transversely on a conveyor belt 8 deflected on end pulleys 9-10 (Figures 2- 3) positioned above and in the region of the ends of said guide 2, the first of these pulleys being idle and equipped with a tensioner 109 while the other pulley is connected to a movement shaft 110 (see Figure 5) . The upper return branch of the belt 8 (Figures 2-3) is kept distant from the guide 2, with a broken-line course, by virtue of deflection on an intermediate idle pulley 11 positioned in the region of the highest point of the curved section 302 of said guide 2. The lower branch of the conveyor belt 8 is kept equidistant from and in the vicinity of the guide 2, with initial deflection on the idle pulleys 9-12 which arrange it parallel to the initial section 102 of said guide 2 and with deflection of the intermediate section on two parallel and opposite rows of small wheels 13-113 (see also Figure 4) which interact with the edges of the belt left free by the pushers 7 and which arrange the lower branch of the belt itself with the necessary equidistance in relation to both the parabolic section 302 and the rectilinear

sections 202 and 402 following this of said guide 2. From Figures 2-3-4, it can be seen that the small wheels 13- 113 are mounted on vertical support plates 14-114 with a curved lower edge, which are fixed to the plate 6 by means of respective distance pieces 15-115 which are added or integral.

From Figure 2, it can be seen that the ascending section 202 of the guide 2 is interrupted for a portion of length greater than that of a article 1 and is formed by a separate segment of rail indicated by 103, supported via the upper end by a fork 16 articulated transversely at 17 to the plate 6, in the region of the ends of a tie 5, this fork being connected to an electromagnetic oscillation actuator 18 which, when operated, can bring said segment 103 of rail from the position indicated in Figure 2 with a continuous line to the raised position indicated with a dashed line to unload from the guide 2 any faulty articles. Any actuation of the actuator 18 modifies the functioning of the components downstream of the conveyor in question as described below.

To facilitate ordinary and extraordinary maintenance interventions on the curved section 302 of the guide 2, it is possible to envisage that this section of guide can be isolated from the consecutive rectilinear sections and supported via the ends of forks 19-20, one of which is fulcrumed transversely at 21 to the plate 6, in the region of the ends of a tie 5, while the other is equipped with a forked groove 22 with which it can be fixed removably to a clamp 23 fixed in a cantilevered manner to the same plate 6. When necessary, by releasing

the fork 20 from the clamp 23, it is possible to lower the section 302 of guide with oscillation on the fulcrum 21.

The conveyor for feeding the articles is completed by covers 24-25 preferably made of transparent material which have a profile shaped like an upturned "L"

(Figure 4) and are fulcrumed on the upper edge of the plate 6 with hinges 26-27 (Figures 2-3) and which, in the active position, are arranged with one of their walls parallel to the same plate 6 to bring about effective anti-accident protection.

Suitable means can be provided to avoid the articles escaping by gravity the pushing action exerted by the associated rear pusher 7 as they pass through the last, descending section of the guide 2. These means can, for example, consist of small brushes indicated diagrammatically by 28 in Figure 5 which are fixed on the lateral guide profiles 4-104 and arranged to act on the longitudinal edges of the articles being conveyed to brake them slightly and ensure that they advance essentially by the action of the pushers 7. Other means can be used for this purpose. It is, for example, possible that there are fixed on the conveyor belt 8, in front of the pushers 7, sponge rubber pads (not illustrated) which perform their action of retention of the articles in the last and most critical sections of the transport by virtue of the guide 2 progressively drawing closer to the active branch of the same conveyor belt 8. To avoid the article being damaged by scraping on the rail 3, under the pushing action of said pads, the

rail can be replaced in part by a track of idle rollers or can be covered longitudinally by the upper branch of a belt which may be motorized for connection to the axle of the driving pulley 10, all of which is intuitable and easily achievable by experts in the field.

From Figures 1-3-6, it can be seen that there is provided, perpendicularly to the longitudinal axis of the last rectilinear section 402 of the guide 2, and at a short distance therefrom, a horizontal shaft 29 on which there are mounted in an idle manner four identical pulleys 30-31-130-131 side by side, said shaft being supported via the ends by supports 32 mounted with registers 33 on a frame 34 which bears rotatably two other shafts 35-36, the first of which lies in an ideal horizontal plane which also bears the shaft 29 while the other lies in an ideal vertical plane which bears said shaft 35. Mounted on the shaft 35 are four toothed pulleys 37-38-137-138 (Figure 6) and mounted on the shaft 36 are four other toothed pulleys 39-40-139-140 which are all identical with one another and with those mounted on said shaft 29. The pulleys 38-138 are keyed on the shaft 35 while those 37-137 are idle. The pulleys 39-139 are keyed on the shaft 36 while those 40-140 are idle. Deflected on the pulleys described are four toothed and identical belts 41-42-141-142 and the shafts 35-36 are connected to respective driving means diagrammatically indicated by 43-44 in Figure 3, on which more will be said below.

From the Figures 1-3-6, it can be seen that, on the belts 41-141, there are arranged on edge,

transversely and one following another, pairs of rectangular and identical panels 45 which have a profile shaped like an isosceles triangle and are fixed by the base to said belts. The empty space which exists between two successive pairs of panels 45 forms a stall, in which it is possible to accommodate on edge a article 1 originating from the guide 2 already considered. Arranged on the belts 41-141 just mentioned is a first group of panels 45 which form a first group of stalls 101 and a second group of panels 45 which form a second group of stalls 201 opposite the first.

Arranged on the belts 42-142 are two groups of panels 45 which are identical to those already considered and which form two corresponding groups of stalls 301-401 opposite one another.

The linear distance which exists between one group of stalls and that immediately following, mounted on the various belts just mentioned, is preferably identical or expediently greater than the length of one of these groups.

The groups of stalls considered have an identical containment capacity and each group is capable of bearing as many articles as are necessary for filling a box.

The apparatus in question is completed by a logic unit 48 which controls the motors 43-44, and also the motor 49 of the pulley 10, and to which optoelectronic sensors 50-54-154 are connected, the first of which acts immediately downstream of the last rectilinear section 402 of the guide 2 while the others are located to detect the correct position of the stalls in the filling station

and in the unloading station of the articles respectively.

From Figure 3, it can be seen that at the beginning of a work cycle the group of stalls 101 interacts at the front with the sensor 54 and the first of the same stalls is aligned with the end section 402 of the guide 2 to receive a article 1 from it. Turning around the shaft 29 with the pulleys 30-31-130-131, the panels 45 which define the stalls 101 in the phase of loading the articles are arranged in a fan-like manner with an increase in the distance which exists between their free ends close to the guide 2 so as to facilitate entry of the article into each stall.

When entry of a article into a stall 101 has taken place, the sensor 50 detects this state and brings about the actuation of the motor 44 which controls the advance of the belts 41-141 by an amount necessary to align a successive empty stall 101 with the guide 2.

While the group of stalls 101 is progressively filled with articles, the group of stalls 301 which has been filled in the preceding cycle and which is positioned on the upper branch of the associated conveyor with belts

42-142, in the region of the sensor 154, is aligned with a lateral station which bears, open and arranged horizontally, a box 51 (Figure 1) , into which the articles positioned in said group of stalls are transferred contemporaneously by a pusher 52 of known type and by means of a likewise known hopper 53 positioned in a bridge-like manner between the stalls and the box and also having the function of compacting in

width the group of articles to be boxed. The actuation of the pusher 52 is controlled by the unit 48 by means of the connection 152 (Figure 3) . When the boxing of the articles has taken place, the pusher returns to rest, the full box is removed and replaced by another box to be filled and the motor 43 is actuated in conjunction with the motor 44 in any manner so that, when the group of stalls 101 is full, this must be capable of being replaced rapidly by the successive group of stalls 401 so as to ensure continuity of functioning of the system for feeding the articles. The group of stalls 101 full of articles moves into the place of that 301 in Figure 3 and the cycle described is repeated.

It is understood that, instead of the sensors 54- 154, use can also be made of speed and phase control motors 43-44, for example brushless motors.