Field of Invention:

The invention relates to the means provided in belt curve conveyors to hold the belt on the curve conveyor against the centrifugal pull exerted during running of the belt . In the operation of belt curve conveyors , the belt experiences a radial force, which tends to pull the belt off the conveyors . So, the means provided to retain the belt on the curve conveyors becomes vital and important for the proper functioning of the belt curve conveyors and this invention pertains to one such type of means having the advantage in the maintenance of curve conveyors as compared to other existing known means .

. Background of the Invention

From US Patent No 4 , 955 , 466 and DE 195 , 35 , 384 , the curve conveyor belt is provided with an enlarged bead, which is captured between upper and lower angled rollers is known. From U. S . patent no . 5 , 394 , 977 , an apparatus and method of replacing the curve conveyor belts is also known. Also, from the U. S Patent No . 5 , 857 , 559 and 5 , 944 , 171 , a belt curve conveyor with entirely different methods of holding the curve belt in place is disclosed.

Known belt curve conveyors tend to have different methods of belt holding system which in turn determine the extent of difficulty of maintenance and time requirement for replacements , thus affecting the availability of the equipment . This is especially the case with replacement of belt which requires disassembly of virtually the entire holding brackets and conveyor sections in some cases . Additionally, difficult alignment procedures have to be followed once again as the holding brackets are displaced, thus adding to the downtime of the conveyor undergoing maintenance or installation which affects the availability of the system. So, said known curve conveyor is satisfactory per se , but in some cases there exists a need for an improved belt holding system that is simple , compact and in which it is relatively easy to install and replace curve belts .

J3uinmary of the Invention

The present invention provides for a conveyer system having a first and second plates (6) , (9) ; a first guide roller (7) for engaging a collar bead (10) on a first side of the belt (2 ) and mounted on the first plate (6) ; a second guide roller (V ) for engaging the collar bead (10 ) on a second side of the belt (2 ) and mounted on the second plate (9) , the second plate (9) rotatable with respect to the first plate (6) to engage and disengage the first and second guide rollers (7) from the first and second sides of the belt (2 ) .

Brief Description of the Drawings

The invention will be explained in more detail hereafter with reference to an embodiment of the construction according to the invention which is diagrammatically illustrated in the following Figures .

Fig . 1 is a diagrammatic plan view of belt curve conveyor, showing several rollers supported on a frame ;

Fig . 2 is a front view of a pair of guide rollers supported by a common support along with a lock mechanism;

Fig . 3 is a sectional view of the Fig . 2 , along line 3 - 3 in Fig . 2 ;

Fig . 4 is a view of key handle for lock;

Fig . 5 is a perspective view of the holding system assembly in "lock" position; and

Fig . 6 is a perspective view of the holding system assembly in "open" position .

Detailed Description of the Invention

As is diagrammaticalIy shown in Fig . 1 , a belt curve conveyor 1 includes an endless belt 2 driven by a driven pulley 3 and an idler pulley 4. As is conventional , the endless belt 2 has a shorter inner length than an outer length . Endless belt 2 is preferably a single piece of belt material formed into a ring-shape . Endless belt 2 is also preferably a single belt connected at its ends by belt splicing devices , such as fasteners or mechanical lacing or vulcanized. Furthermore , the endless belt 2 is reinforced by stitching at the outer edge using a specially designed proj ecting collar bead 10 for holding purpose . Pulleys 3 , 4 are tapered to frictionally engage with the endless belt 2 over its full width so that the endless belt 2 which is stretched between two pulleys can be driven by driven pulley 3 using_..drive . motor 5.

Referring once again to Fig . 1 , there are belt holding assemblies 6 near the outside of the bend described by the endless belt 2. A plurality of such belt holding roller assemblies 6 is disposed along the outer edge of the curve .

As will be apparent from Figs . 2 -6 , said belt holding assemblies 6 are arranged in pairs of two guide rollers 7 , V one above the other to hold carrying and return side of the endless belt 2. Further more, the inner guide rollers V are connected to a lock assembly 8

using a supporting plate 9. This lock assembly 8 is fitted on the main frame of the holding assembly 6.

The two guide rollers 7 and 7 ' positioned one above the other make contact with the proj ecting collar bead 10 of the endless belt 2. During running of the conveyor belt 2 , the centrifugal radial force generated will make the endless belt 2 to shift inward towards the center . However, the guide rollers 7 , 7 ' which are in contact with the bead 10 of the endless belt 2 prevent the inward shifting of the belt 2 , as a result of which the desired movement of the endless belt 2 will be maintained .

During the belt 2 replacement , the inner guide rollers 7 ' will be rotated to "open" position as shown in Fig . 6 , by operating the lock assembly 8 using the key handle 11. After all the holding assemblies are turned in to "open" position, the inner guide rollers 7 ' are no longer in contact with the bead 10 of the belt 2 at the bottom sides and the belt 2 can be pulled out easily.

The steps to be carried out to remove the endless belt 2 are as follows :

1. Using the key handle 11 , make all holding assemblies 6 into "open" position;

2. Loosen the belt 2 by dismantling the pulleys 3 , 4 at inner ends ,-

3. Press the belt 2 at ends to get it released from guide rollers 7 and pull it out from sideways .

4. Repeat the process in reverse order for installation of a new endless belt 2.

As will be apparent from the above, the above described belt holding system is relatively simple with less number of parts and without dismantling the holding assemblies for belt installation and replacement .

Although the present invention has been described in detail with respect to the illustrated embodiment , it should be understood that various changes , substitutions and alterations can be made thereto without departing from the spirit and scope of the invention as defined by the appended claims .