WO1988007969A1

WO1988007969A1 - Conveyor belt assembly

Info

Publication number: WO1988007969A1
Application number: PCT/GB1988/000265
Authority: WO
Inventors: Christopher Fenlon
Original assignee: Fenlon, Richard
Priority date: 1987-04-06
Filing date: 1988-04-06
Publication date: 1988-10-20
Also published as: GB2224708B; GB2224708A; GB8708199D0; AU1542988A; GB8922522D0

Abstract

A conveyor assembly, e.g. comprising a parallel array of belt loops (18) extending around drive (10) and driven (12) rollers, has arms (28) displaceable to control the conveyance of goods. Thus there may be L-shaped levers (20) mounted pivotally (32) between belt loops (18). A downwardly extending actuating arm portion (30) is displaceable by a hydraulic actuator (35) to a configuration in which it is retainable by an electromagnet (32), while a horizontally extending arm portion (28) is caused to project above the belt surface (18) to prevent conveyance of goods at that transverse location. The hydraulic actuator (35) may be arranged to pivot all of the arms (20), whereas they are retainable by the electromagnets (32) individually or in groups. The passage of goods may be detected by a photocell device (38). The retention and releasse of goods may be under the control of a computer (34).

Description

CONVEYOR BELT ASSEMBLY

Background of the Invention

This invention relates to a conveyor assembly with means for selectively controlling the conveyance of items. A conveyor of such type is useful, for example, in production lines where there is a requirement to regulate the transfer of items between work stations associated with the production line.

Summary of the Invention

The invention provides a conveyor assembly having means for selectively controlling the conveyance of items comprising a plurality of arms displaceable to permit or prevent the conveyance of selected items. For example the conveyor assembly may comprise a plurality of conveyor loops with a plurality of lifting arms arranged such that they may be elevated between said conveyor loops. The lifting arms may be retainable in elevated position by electromagnets which are switchable to retain or release selected arms. The arms may be pivotable to the elevated configuration. They may be elevated by a hydraulic actuator which acts to displace a plurality of arms so that they are retainable by respective electromagnets. The actuation of the electromagnets may be computer controlled. In order that the invention may be more clearly understood one embodiment will now be described with reference to the accompanying drawings. Brief Description of the Drawings Fig. 1 is a schematic longitudinal section of the embodiment_? and

Fig. 2 depicts the embodiment in plan view. Description of the Preferred Embodiment

The illustrated conveyor assembly comprises two horizontally spaced rollers (a drive roller 10 and a driven roller 12), rotatably mounted via respective axles 14,16 extending between side walls 17 of a casing. Drive means (not shown) are couplable to the drive roller 10 for rotation. The rollers 10 and 12 are linked by a composite conveyor belt 13 formed of a plurality of spaced parallel narrow belt loops 18. The loops 18 are located by means of circumferential grooves 11, in the rollers. Corresponding grooves 11 on each roller are in register such that the loops extend perpendicular to the axes. The loops are tensioned sufficiently to drive the driven roller 12 from the drive roller 10.

A number of narrow lifting levers 20 are pivotally mounted generally below the upper run 22 of the conveyor belt. Each lever is an approximately L-shaped plate in a plane between two loops 18. (There may be an arm 20 between each adjacent pair of loops 18.) Each lever has a longitudinally extending lifting portion 28 and an actuating portion 30, extending downwardly from the end of the lifting portion 28 close to the driven roller 12. The pivot 32 is adjacent the angle of the lever 20.

The lifting portion 28 has an upper support surface 29 which, in the rest configuration of the lever 20 shown in Fig. 1, lies just below the upper surface 22, of the conveyor belt, its depth increasing away from the pivot 32.

The actuating portion 30 ends beneath the return run 31 of the conveyor belt where it extends in the gap between a respective electromagnet 32 and a hydraulic actuator 34. The hydraulic actuator 34 includes a pump means P operable to displace one or more piston assemblies 35 linked to an actuator bar 36 which extends across at least a part of the width of the conveyor assembly. On the side of the actuating portion 30 adjacent to the electromagnet, the lever 20 bears an armature plate 37 of ferromagnetic material such as soft iron.

The arrangement is such that actuation of the piston assembly 35 urges a plurality (perhaps all) of the levers 20 to pivot so that a lever 35 will be magnetically held by attraction of its armature plate 37 to an electromagnet 32 if that magnet is actuated. This pivoting brings the support surface 21 into a substantially horizontal plane above the upper surface 22 of the conveyor.

Levers 20 may be displaceable individually, each having its own magnet 32. Alternatively they may be linked, e.g. in pairs, suitably by means of blocks and screws. The upper run 22 of the belt may run on a support surface (not shown) having slots for the levers 20.

A sensor 38 for detecting articles carried by the conveyor is located a short way above the conveyor belt 13. It may employ a light source and a photocell.

The assembly may be operated as follows. The drive roller 10 is driven to rotate the belt anticlockwise. Goods are intermittently passed onto the belt at the driven roller end, and carried leftwards. Arrival of goods at the sensor 38 is detected, whereupon the hydraulic actuator 34 pivots the levers 20 and raises the goods above the conveyor. They are maintained raised by the magnets 32. (Optionally, the motion of the conveyor may be stopped.) Selected goods, that is, goods supported by selected levers 20 or groups of levers 20, can be returned to the conveyor by switching off the associated magnets 32. The switching may be controlled by a computer 40. This may receive input data from the sensor 38.

For example, a row of goods can be retained by the array of levers, and individual items or groups can be despatched at predetermined intervals, e.g. determined by the requirements of apparatus downstream of the conveyor assembly and/or a program previously fed into the computer 40.

Although it has generally been assumed in the above description that the actuator 34 acts on all levers 20, this need not be the case. For example there could be several conveying lanes, each with an individual actuator 34 and/or sensor 38. Likewise the belt loops 18 need not be driven in concert by unitary rollers 10,12. Thus individual lanes can be fully controllable by the computer

Claims

CLAIMS :

1. A conveyor assembly comprising means (18) defining a displaceable conveying surface; characterised in that it further includes arm displacement means (32-36); and a plurality of arms (20) displaceable by said arm displacement means (32-36) relative to the conveying •surface (18) between configurations in which they respectively permit and prevent the conveyance of goods by the displacement of said conveying surface (18).

2. A conveyor assembly according to claim 1 wherein said conveying surface (18) is displaceable to convey goods in a longitudinal direction; a plurality of said arms (20) are located at respective different transverse locations relative to said conveying surface (18); and means (40,32) are provided for controlling the operation of said arm displacement means selectively so that conveyance of goods is selectively permissible and preventable at different transverse locations.

3. A conveyor assembly according to claim 1 wherein the arm displacement means comprises displacement actuation means (30 for displacing arms (20) to their conveyance- preventive configurations, and electromagnet means (32,37) for retaining arms (20) in their conveyance-preventive configurations . . A conveyor assembly according to claim 3 having a multiplicity of said arms (20) , and wherein the displacement actuation means comprises an actuator '(3^,P) arranged to displace at least a plurality of said arms (20); and the electromagnet means comprises a plurality of electromagnets (32) for retaining said plurality of arms. (20) , and a plurality of switch means ( θ) for said electromagnets whereby selected electromagnets (32) are operable to retain selected arms (20) of said plurality of arms.

5- A conveyor assembly according to claim 1 wherein said conveyor assembly comprises a plurality of conveyor loops (18) having conveying runs which define said displaceable conveying surface; said loops (18) being located side by side; and said arms (20) being located between adjacent loops (18) .

6. A conveyor assembly according to claim 5 wherein each arm (20) comprises a generally L-shaped lever member having two arm portions (28,30) providing a lifting portion (28) and an actuating portion (30) respectively; the arm displacement means (32-36) being arranged to act on the actuating portion; each arm (20) being pivotally mounted (32) adjacent the conveying surface so as to be pivotable between said conveyance-preventive configuration in which the lifting portion (28) projects beyond the conveying surface (18) , and said conveyance-premissive configuration in which the lifting portion is behind the conveying surface (18) .

7- A conveyor assembly according to claim 1 having means (38) for detecting the presence of goods on the conveying surface, and means ( 40 ) for controlling the arm displacement means in response to data from the detection means .