Machine for transferring objects aligned in rows

A machine for transferring in successive rows objects initially aligned on a first conveyor. A second conveyor comprises a tray lateral to the first conveyor and a device for displacing objects with at least one push-member mobile transversely to the first conveyor such that it is urged into lateral contact with n objects on the first conveyor to push them back together in a row onto the tray along a direction forming an angle θ ranging between 0 and 90° exclusively relative to the first conveyor. Thus, the objects have speed components which are never null along the directions of movement the conveyors.

BACKGROUND OF INVENTION

The present invention relates to the field of transferring objects, and more specifically it relates to the transfer in successive rows of initially aligned objects.

DESCRIPTION OF RELATED ART

Document GB-A-2 174 667 describes a machine for transferring objects comprising:a first conveyor suitable for bringing the objects placed in line one after the other,a second conveyor extending perpendicularly to the first conveyor with its entrance end adjacent to the latter,and a pushing bar extending transversely to the direction of the second conveyor and movable parallel to the direction of the latter so that it comes into lateral contact with n objects on the first conveyor in order to push them together, in a row, onto the second conveyor.

The fact that, in this known machine, the first and second conveyors are perpendicular to one another constitutes a marked drawback due to the change of direction of movement of the objects, corresponding to the transfer from the first conveyor onto the second conveyor under the action of the pushing bar, which causes a canceling out of speed of the objects in the direction of movement of the first conveyor, immediately accompanied by a speeding up of the objects in the direction of the second conveyor. In other words, the objects undergo a first deceleration in the direction of movement of the first conveyor, followed by a second acceleration in the direction of movement of the second conveyor.

If the pushing bar acted directly on the objects reaching it, the initial deceleration and the following acceleration would be very considerable, and the objects would be unbalanced and would fall over.

To lessen this abruptness of the transfer, this document proposes to mount the pushing bar on a carrier mobile parallel to the first conveyor, the bar remaining movable, relative to the carrier, parallel to the second conveyor. It then becomes possible, by combining the two possible movements of the pushing bar, to transfer the objects from one conveyor to the other on more or less complex trajectories which substantially reduce the degree of the accelerations sustained by the objects.

However, the machine thus equipped becomes complex and costly.

In addition, a change of trajectory of an angular amplitude of 90° may not suit all users.

SUMMARY OF INVENTION

The essential aim of the invention is to propose a perfected solution which keeps the machine to a simple structure while avoiding the aforementioned disadvantages.

For this purpose, the invention proposes a machine for transferring initially aligned objects in successive rows, comprising a first conveyor suitable for bringing the objects placed in line one after the other, characterized in that it comprises a second conveyor comprising a tray placed to the side of the first conveyor and means of moving objects with at least one pushing member movable transversely to the first conveyor so that it comes into lateral contact with n objects on the first conveyor to push them together in a row on the abovementioned tray while moving them in a direction making an angle θ lying between 0 and 90°, limits excluded (θ≠0, θ≠90°) relative to the first conveyor.

Thanks to this arrangement, while keeping a machine of simple structure, the objects have speed components in the directions of movement of the two conveyors that are never zero: this reduces the magnitude of the accelerations or decelerations sustained by the objects and the result is a greater stability of the objects when passing from one conveyor to the other. The result is the possibility of increasing the speed of transfer of the objects, an advantage which fits perfectly with the current concern of the packagers who wish, as far as possible, to use a minimum number of packaging lines operating at as high a speed as possible.

In order that the transfer is carried out in the best conditions, it is desirable that the angle between the two conveyors lies between approximately 20° and 70°, the optimum result being obtained for an angle of approximately 45° for which the variation of the speed components is minimal.

In a practical embodiment, the second conveyor is suitable for moving the objects on a substantially rectilinear trajectory and the second conveyor comprises several pushing members which are substantially parallel and supported by endless running support means extending in a plane approximately perpendicular to the plane of transfer of the objects. Said endless running support means may then comprise an endless chain supporting the pushing members overhanging at one of their ends; or, as a variant, said endless running support means may comprise two parallel endless chains supporting pushing members by the respective ends of the latter.

In another possible embodiment, the second conveyor is suitable for moving the objects on a curvilinear trajectory and this second conveyor comprises several pushing members supported by support means mobile on a partially closed curvilinear trajectory parallel to said trajectory of the objects. It can then be arranged for the support means to be rotatable about a vertical shaft and for the pushing members to be radiating in an overhanging manner, or else for the support means to comprise at least one endless chain opening out in a curvilinear manner parallel to the tray and for the pushing members to radiate in an overhanging manner.

In one embodiment, the first conveyor moves the objects placed one after the other and each pushing member is brought laterally to the first conveyor in order to contact the first n objects present on said first conveyor, the objects on the first conveyor then being able to be juxtaposed to one another or to be separated from one another by a given pitch.

In another embodiment, the objects on the first conveyor are separated from one another by a given pitch and the pushing member is interposed between the object numbers n and n+1 (counted from the first object at the head of the first conveyor). In this case, if the objects are moved by the first conveyor while being to one another, separator means are associated with the first conveyor (for example of the rotating star wheel type) suitable for separating the objects from one another at a given pitch.

In another embodiment, the first conveyor is associated with grouping means suitable for establishing a given gap between the object numbers n and n+1 (counted from the first object at the head of the first conveyor) and the pushing member is interposed into the gap created between said object numbers n and n+1.

In practice, irrespective of the embodiment, it may be advantageous for the pushing members to be bars.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

With reference first of all toFIGS. 1A and 1B, a first conveyor1(motor-driven conveyor, for example of the belt or tray conveyor type, or motorless conveyor) brings (arrow3) objects2(for example bottles as illustrated) disposed in line one after the other; in the example illustrated, the objects2are juxtaposed to one another, although this disposition is not necessary as will appear hereinafter.

A second conveyor4clears (arrow5) the objects2disposed in successive rows6of n objects abreast.

For this purpose, the second conveyor4comprises objects movement means7with at least one pushing member made up in the form of a pushing bar8which is movable (arrow5) in order to be brought into lateral contact with n objects aligned on the first conveyor to push them, together, onto a tray10of the second conveyor where they are disposed in a row of n objects. The tray10extends laterally to the first conveyor1as appears inFIG. 1A.

The first and second conveyors1and4are disposed so that the directions3,5of transfer of the objects on the first and second conveyors1and4respectively form an angle θ between them.

According to the invention, the angle θ formed by the two conveyors1and4lies between 0 and 90°, limits excluded (that is to say θ is neither 0—the two conveyors1and4are not parallel—, nor equal to 90°—the two conveyors are not perpendicular to one another).

This disposition ensures that the objects are transferred from the first conveyor1to the second conveyor4without a sudden loss of speed on exiting the first conveyor1and without a sudden increase of speed on entering the second conveyor4. InFIG. 1C, a vector V1represents the speed of the objects2on the first conveyor1(schematized by the axis1). The vector V1is directed in the direction of movement of the conveyor1and forms an angle θ with the second conveyor4(schematized by the axis4). The vector V1is projected onto the axis4as a vector V1′ such that
V1′=V1cos θ

It can therefore be seen that, during its transfer onto the second conveyor4, each object2already has a speed component V1′ in the direction of movement of the second conveyor and that, if the pushing bar8of the second conveyor4moves at a speed V4, the increase in speed sustained by each object is V4-V1′, or V4-V1cos θ. This reduces the accelerations to which the objects are subjected during the transfer from one conveyor to the other and this then increases the stability of the objects. It can in particular be arranged so that V4=V1, in which case the increase of speed is equal to V1(1−cos θ).

In practice, the arrangements according to the invention seem that they must offer the best advantages if the angle θ lies between approximately 20° and 70°. For given speeds V1and V4, the most advantageous result is obtained for an angle θ of approximately 45° (the case illustrated inFIGS. 1A and 1C).

For the practical embodiment of the main dispositions that have just been given, use is made of the following arrangements.

With respect to the object movement means7, the use of a single pushing bar with alternating movement as illustrated in the aforementioned document GB-A-2 174 667 does not seem very practical due to the relatively long travel and above all due to its alternating movement which prevents the achievement of high rates desired by the users.

In the context of the present invention, it is therefore proposed to arrange, in a first embodiment, the object movement means7with several pushing bars8evenly spaced and parallel with one another, which are supported by endless running support means11(such as at least one endless chain). Said support means extend in a plane approximately perpendicular to the tray10and move the bars8in the vicinity of the surface of the conveyor1and of the tray10in the pushing phase of the objects2and above the objects in the return phase. Finally these means may appear as illustrated inFIG. 1B, in the form of an endless chain11which supports a plurality of evenly spaced pushing bars8which roll round in a closed loop on idler pulleys on any required trajectory.

Two arrangements can be envisaged.

In the example illustrated inFIG. 1A, the object movement means7comprise two endless chains11disposed parallel with one another above the plane of transfer formed by the first conveyor1and the tray10of the second conveyor4, and on either side of or on the sides of the latter. Thus, the pushing bars8are supported at their two ends respectively by the two endless chains11.

In this case, each pushing bar8needs to be introduced perpendicularly between two consecutive objects present on the first conveyor1. The simplest embodiment consists in bringing the bars8from above, as illustrated inFIGS. 1A and 1B. It is therefore necessary:either to separate the groups of n objects as illustrated inFIG. 3, by implementing separator means12of any appropriate type known to those skilled in the art (for example lateral separator with intermittent brake),or to systematically separate all the objects2by a given pitch p as illustrated inFIG. 4, by implementing spacing means13of any appropriate type known to those skilled in the art (for example rotating star wheel),
if the conveyor1receives the objects juxtaposed as illustrated inFIGS. 1A,1B.

In the example illustrated inFIGS. 2 and 4, the object movement means7comprise a single endless chain11disposed unilaterally and supporting the pushing bars8in an overhanging manner at just one of their ends. Such an arrangement may be used in the same conditions as explained hereinabove, with spacing of the objects2or groups of objects2.

However, this arrangement with pushing bars overhanging has the additional advantage of being able to be implemented with juxtaposed objects, as illustrated inFIG. 2. Each pushing bar8is then brought via the side of the first conveyor1which is opposed to the second conveyor4, so that its free end comes into contact laterally with the object number n to push the latter, then successively the others. The implementation of this arrangement requires the objects to be sufficiently large to be sure that the free end of each pushing bar contacts only the object number n, without touching the object number n+1; this arrangement may be suitable in particular (although this is not exclusive) for moving objects having flat faces, such as “bricks” as illustrated inFIG. 2.

FIG. 5illustrates a top view of a concrete example of a transfer machine implementing the arrangements according to the invention. In this example, the objects2, carried along by the first conveyor1and juxtaposed one after the other, are separated into groups of six aligned objects by the separator means12here taking the form of a rotating star wheel14driven by means15arranged to cyclically cause a space between two objects. The object movement means7of the second conveyor4are of the pushing bar8type supported in an overhanging manner by a unilateral chain11. Guides15are associated with the tray10to guide the objects (resting against a pushing bar8) moving on the tray10of the second conveyor4, so as to assemble and keep the n objects juxtaposed in a row6. In the example illustrated inFIG. 5, the second conveyor4brings the rows6of objects to a third conveyor16(for example a motorized conveyor of the belt or tray conveyor type, itself consisting of a succession of conveyors161,162,163having different speeds in order to receive the successive rows6of objects without the latter sustaining excessive decelerations, on the one hand, then finally so as to assemble several successive rows in order to form a batch17of a plurality of objects2assembled in lines and columns, for example to feed a packaging machine.

In the examples given inFIGS. 3 to 5, it is indicated that the pushing bars8were brought from above into the gaps between the objects or groups of objects, because this is the technical solution which seems the simplest due to the fact that the bars8are then moved above the conveyor1and the tray10. However, if necessary and technically feasible, the bars could equally be brought from below into said gaps.

FIG. 6illustrates another embodiment in which the object movement means7are of the rotary type, with a vertical axis hub18supporting the radiating pushing bars8. The hub18may be disposed in such a manner that each pushing bar8arrives above the first conveyor1at an angle θ as defined hereinabove: the angle θ here is the angle formed between the center line of the first conveyor1and the tangent to the circular trajectory (arrow5) of the bar8in the place where the latter intersects the center line of the conveyor1. The objects2are then pulled, by each pushing bar8, into a row6on an arced trajectory. The tray10is arranged in consequence and it may advantageously be fitted with an external guide such that the objects2, aligned in a row6and bearing against the bar8, follow an arced trajectory without drifting outward.

FIG. 7illustrates another embodiment which combines the aforementioned dispositions. The objects movement means comprise a support means11elongated in a closed loop such as an endless chain which winds around any curvilinear contour desired: elliptical, oval, or other contour. The objects may then be carried along a complex path, for example a substantially rectilinear section followed by an arced section, as illustrated inFIG. 7. The support means11is then supported by wheels19disposed and dimensioned in the manner required to suit the trajectory (arrow5) to be achieved.

Note also that it is possible to produce transfer machines of greater capacity, comprising several first conveyors disposed parallel with one another and a second, wide conveyor or several second conveyors disposed parallel to one another, the pushing bar movement means engaging the objects simultaneously on the first conveyors and transferring them in a row or rows onto the second conveyor or onto the second conveyors simultaneously.

In the various examples explained hereinabove, it has been considered that each pushing member was made in the form of a bar. This bar may be made in any appropriate form: single bar as illustrated in the drawings, bar with notches or recesses shaped to suit the shape of the objects, bar bent at the end (particularly for conveyors4of the rotating type, in order to prevent the objects from sliding outward under the action of centrifugal force), etc. The pushing members may also be made in any other form appropriate to the pushing function: plate, set of palettes, etc.