FR2585679A1 - Automatic centring device for return strand of belt conveyor - Google Patents

Abstract

The invention relates to a device intended to automatically centre the return strand of conveyor belts. Centring is obtained by the orientation of 2 rollers pressed, respectively, on the top and the bottom of the belt and which are oriented about a pivot through the effect of a differential force. The belt undergoes no transverse deformation and its edges are not stressed. The device according to the invention consists of 2 rollers 1 and 2 supported by lateral plates 3 associated via a crosspiece 4 which can be oriented in a sleeve 5. The assembly is articulated in a pivot 6, 7. Decentring of the belt according to F or G creates a differential force which causes rotation according to F1 or G1, which places the rollers 1 and 2 in a correcting position, returning the belt in the direction G or F. This principle can be used on all apparatuses which comprise an endless belt.

Description

DEXCRIPTO
Centering device for belt conveyor.

The device which is the subject of the present invention constitutes a component of belt conveyors used in many industries and more particularly in mines and quarries.

 Its role is to regularize the centering of the endless belt, in particular in the lower zones called the return strand.

The bands generally rest on rollers perpendicular to the axis of movement of the products transported.

The position of the upper rollers forming a "trough" is such that there is a permanent centering force due, on the one hand, to their angle in the transverse plane but also to an inclination in the direction of travel called "centering angle1, .

 It is not the same for the lower strand which moves according to the orientation of the rollers and the disturbing action of the coatings of products which may occur there.

 It is therefore necessary to constantly modify the orientation of the lower rollers, failing which the strip deteriorates by rubbing on the frames.

 Centering is sometimes maintained by vertical and lateral rollers on which the edges of the strip are supported and deteriorate.

 There are also self-centering rollers which orient themselves around a pivot under the action of vertical (and lateral) rollers which touch the edges.

 It also uses stations or trough mounted upside down relative to the troughs defined by the rollers supporting the upper strand. This then takes advantage of the trough constraint and the centering angles of the outer rollers.

 All these devices are not very effective because the centering action is dependent on the weight of the strip on the roller.

They also enter a fatigue of the strip which can go to its deterioration, either by the edges in the side roller systems, or by the middle part in the trough systems.

 The object of the invention is to provide a device which makes it possible to avoid these drawbacks by keeping the strip substantially flat in the transverse direction and without any stress on the edges.

 The device according to the invention comprises 2 rollers held in a sunport orientable in 2 planes.

10) in the horizontal plane to ensure a contact pressure of
the strip on the 2 rollers, one of which is placed above and one
be below.

 The contact pressure is therefore independent of the weight of the strip.

20) In the vertical plane to automatically orient the assembly in
according to the necessary corrections.

According to a 1st characteristic of the invention, the centering device is constituted under the rep. in the drawings of 2 rollers (1 and 2) arranged spaced 'from each other with respect to the direction of movement of the strip (8) and intended one to be placed above and the other below.

 The ends of said rollers are supported by the lateral flanges (3) of a support assembly (3-4) provided with a pivot (6) in its middle part whose axis is contained in a plane perpendicular to the axes of the rollers .

 Said pivot (6) is provided with connecting means (7) to the frame of the conveyor.

According to another characteristic, the support flanges, under the RP of rep.

to the drawings (3) are linked by a transverse element (4) arranged outside the plane of the rollers (1 and 2) which is held by an orientation sleeve (5) on the end of the pivot (6).

 Said sleeve (5) is placed in a plane perpendicular to the axis of the pivot, which allows the contact pressure of the rollers (1 and 2J on the strip) to be adjusted.

According to a last characteristic, the transverse element, under the BP of rep. in the drawings (4) is cylindrical and the orientation sleeve (5) comprises a means for adjusting the orientation and a clamping element capable of immobilizing the transverse element on the orientation sleeve.

The operation of the device is as follows. b
The stress of the strip on the rollers which it generates generates a force oriented in the direction of travel (of the strip) which is balanced on either side of the pivot point of the assembly.

 The off-center of the strip causes an increase in the effort on the side where the load on the rolls increases and conversely, a decrease in the effort on the least stressed side.

 This differential effect results in a rotation council which is exerted on the assembly and makes it rotate.

The ivoteent nrovoque the orientation of the 2 rollers in the direction in which their combined weésées tends to bring back the strip to its point of centering.

 As a result, the strip does not undergo transverse deformation and its edges are never stressed.

The accompanying drawings illustrate the basic principle of the device, the various elements of which can be the subject of various embodiments.

Figure 1 shows the device seen in perspective, Figures 2 and 3 show a plan view illustrating the lateral movements of the strip and the corrective movements resulting therefrom.

A support which can be tilted at will by a transverse bar (4) in a clampable sleeve (5), receives by its flanges (3) two rollers 1 and 2 intended to be placed respectively above and below the strip (8). The sleeve (5) is integral with a vertical axis (6) which rotates freely in a bearing (7) constituting the point of attachment of the device to the frame of the conveyor.

 If we consider a direction of travel S, decentering along F n will cause a rotation of the vertical axis (6) along F 1 which will orient the 2 rollers (1 and 2) so as to return the strip in the lateral direction onoosé G. (figure 2).

If the decentering is carried out according to G, the rotation will be done following 1 causing an action of the rollers towards F. (figure 3) Industrial explanation
This principle can be used on all devices that include an endless belt.

- Fixed and mobile conveyors
- Extractors, belt dosers
- Machine belts constituting a work table
- Wide nlate belts etc ...

Claims (2)

- CLAIMS 10) Device for centering the return strand endless conveyor belt, characterized in that it consists of 2 rollers (1 and 2) arranged spaced apart from each other with respect to the direction of movement of the band () and intended one to be placed above and the other below  The ends of said rollers are supported by the lateral flanges (3) of a support assembly (3-4) provided with a pivot (6) in its middle part, the axis of which is contained in a plane perpendicular to the axes of the rollers.  Said pivot (u) is provided with means of connection (; /) to the frame of the conveyor. 20) Device according to claim I characterized in that the support flanges (3) are linked by a transverse element (4) disposed outside the plane of the rollers (1 and c) which is held by an orientation sleeve () on l pivot end (b)  Said sleeve (5) is placed in a plane perpendicular to the axis of the pivot, which allows adjustment of the contact pressure of the rollers (1 and c) on the strip 3) Device according to claim <characterized in that l the transverse element (4) is cylindrical and the orientation sleeve (5) comprises a means for adjusting the orientation and a clamping element capable of immobilizing the transverse element on the orienta tison sleeve