VARIABLE SPEED CONVEYOR USING BELTS
The present invention relates to an improvement in the variable speed belt conveyors.
Anti-friction bearing having rolling paths of non-cylindrical shape, which comprise a rigid internal element endowed on its outer surface with a rolling path of non-cylindrical shape, an outer ring having an internal rolling path parallel to that of the said internal element and formed by an endless belt of flexible material, and rolling elements in contact with these rolling paths and interconnected by means of deformable lateral flanges, are known.
The present invention has as its object to allow of the application of such anti-friction bearing having rolling paths of non-revolution type in variable speed conveyors, the endless outer rings of flexible material acting as belts.
The present invention consists in a variable speed conveyor or transporter, which comprises rows of rolling support elements of non-cylindrical shape, which are transversely imbricated wherein the elements are provided with flexible outer rings or belts arranged to be driven respectively at speeds successively variable from row to row, at least at the beginning and end of the conveyor wherein the elements on their upper surface have plane rolling paths wherein the belts are driven in each row by a row of pinions keyed to a common driving shaft and meshing with denticulations wrought on the outer surfaces of the corresponding flexible outer rings or belts, and wherein there are provided spacers having a plane upper surface being situated below that of these outer rings being secured between the rolling support elements in each row, the spacers being adapted to fill the gap between the rolling support element of the preceding and following rows.
The conveyor according to the invention renders it possible to eliminate one of the shortcomings of the conventional conveyors comprising imbricated belts. In point of fact, in case of repairs or belt breakage for a row of belts, it is necessary to perform at least partial dismantling of the preceding and following rows of belts after disconnecting these rows from the overall driving system. For the conveyor of the present invention, in analogous cases, it is sufficient to withdraw the row of belts in question without having to disturb the preceding and following rows.
In the case of variable speed rows, the longitudinal extension of the plane upper rolling paths is preferably substantially equal to the mean length of an adult's shoe. In this way, the passage from one conveying speed to the next occurs along the minimum path without disturbing the person carried.
The drawings illustrate the invention according to one convenient mode by way of example:
FIG. 1 is a diagrammatical plan view of a variable speed conveyor or transporter according to the present invention equipped with anti-friction rolling bearings according to the invention, in its section starting the trajectory;
FIG. 2 is a partial enlarged scale longitudinal section along the line II—II of FIG. 1.
In the form of embodiment illustrated in FIG. 1 and 2, a variable speed conveyor comprises transversal rows of rolling bearings of non-cylindrical shape la to lg comprising rollers 2, these rolling support elements being transversely imbricated from row to row. Their rolling support elements 3a to 3g are arranged in each row on a fixed common spindle 4a to 4g with interposition of spacers Sa to Sg. The flexible outer rings or belts 6a to 6g carry external denticulations 7a to lg which mesh with a common driving pinion 8a to 8g arranged in each row on a common driving shaft 9a to 9g. At their upper part, these rolling support elements have plane rolling paths 10a to 10g. The spacers 5a to Sg have a plane upper surface 11a to llg situated a little below the upper surface of the flexible outer rings and formed to fill the gap between the rolling bearings of the preceding and following rows.
The driving shaft is disposed opposite from the plane rolling paths.
An electric motor 12 ensures the entrainment of the whole of the rows of outer rings 6, each shaft 9 carrying a driving pul
ley 12a to 12g and a return pulley 136 to 13g. The diameters of the driving pulleys 12a to 12g decrease evenly in such manner that the speeds of displacement of the outer rings increase, for example from 0.5 m/s for the outer rings 6a to 5 m/s for the outer rings 6/, that is to say from 1.8 k.p.h. to provide feeble persons with access to the transporter, to a cruising speed of 18 k.p.h. Before reaching this last speed, the rows la to le preferably have equal spacings between the shafts 9, whereas when the cruising speed is reached, this spacing can be increased as in the case of the shafts 9/and 9g.
The rows of rolling support elements are arranged between the sides 14 and 15 of the transporter. An access grid or apron 16 ensures safety at the ingress and egress of the transporter. It j 5 comprises a relatively coarse denticulation 17 which penetrates into the gaps between the rolling bearings la of the first row and into proximity to the spacers 5a.
The rolling support elements 3, at the opposite side from the plane rolling paths 10, comprise two consecutive inflected 20 areas 18 and 19 forming a hollow 20 between them, wherein the common pinion 8 meshes with the outer denticulations 7 of the flexible rings 6, these pinions thus acting as elements for thrusting the rings 6 against the elements 3.
With this embodiment, in case of repair or of belt breakage 25 for the row lc for example, it is sufficient to withdraw this row from the transporter without having to disturb the rows lb and la" with which it is imbricated, contrary to the procedure in the case of a conventional transporter employing belts. According to an advantageous form of embodiment of the 30 variable speed transporter described hereinabove, in the case of rows of rolling bearings at variable speeds, such as the rolling support elements la to le, the longitudinal extension A B of the plane upper rolling paths 10 is substantially equal to ^^ the average length of an adult's shoe, these plane rolling paths succeeding each other with the least possible interruption from row to row. It is thus possible to employ a sufficient number of rows of variable speed rolling bearings, so that passage from one carrying speed to the next, which then oc4q curs along the shortest possible trajectory, does not cause any disturbance of the person carried.
It is quite plain that, without exceeding the scope of the present invention, modifications could be made in the form of embodiment described. Thus, the rolling elements illustrated 45 which are formed from rollers could just as well be formed from balls, pins or tapered rollers. In the case of the variable speed transporter, the end section of the trajectory would naturally be illustrated by a reversed FIG. 1. What I claim is:
50 1. A variable speed conveyor having in the direction of conveyance successive rows of transversely imbricated parallel belts and a transverse driving shaft for each of said rows driving respectively the belts at speeds successively variable from row to row, at least at the beginning and end of the conveyor,
^ the combination comprising, in each of said rows, vertical rolling support elements of non-cylindrical shape parallel to the direction of conveyance, a rolling path plane on the upper surface of each of said elements, rolling elements rolling on
^ said rolling paths of said support elements, flexible belts respectively resting on said rolling elements on each of said support elements, drive means secured on each of said driving shafts and drivingly engaging said belts, said driving shaft for each of said support elements being disposed opposite from
65 the associated one of said plane rolling paths and spacers having a plane upper surface below that of said flexible belts and secured between said rolling support elements filling the gaps between said rolling support elements of the preceding and following rows of belts, whereby each row of belts may be
70 withdrawn for repair without dismantling the preceding and following rows of belts.
2. A variable speed conveyor according to claim 1, wherein in the case of the variable speed rows, the longitudinal extension of the upper plane rolling paths is substantially equal to
75 the average length of an adult's shoe.