Process and device for replacing idler rollers of a belt conveyor

Abstract

A method and a device are provided for replacing individual idler rollers for conveyors, with which a web belt can be lifted and worn-out or damaged idler rollers in upper and lower runs can be individually replaced. The device includes, separately for replacing the idler rollers in the upper run and in the lower run, a subframe (1) for lifting the web belt (7) and for holding the web belt (7), such that a sufficient clearance is formed for replacing worn-out idler rollers (53) by means of a changing frame (2). A service vehicle is equipped with a lifting apparatus for moving dividing devices. The process steps include lifting the web belt (7), removing the old idler roller (53.sup.old), inserting the new idler roller (53.sup.new) and lowering the web belt (7). The drawing shows the use of two dividing devices in the replacing of idler rollers in the upper run.

Claims

1. A process for replacing individual idler rollers of a belt conveyor, the process comprising the steps of: picking up a web belt, in an area of an idler roller station, by a subframe inserted between an upper run and a lower run or between the lower run and the ground surface, the web belt and the subframe being lifted together by means of an external lifting apparatus; setting down the subframe, carrying the web belt while maintaining a cross section, on a support frame of the belt conveyor or hanging the subframe, carrying the web belt while maintaining the cross section, on the support frame of the belt conveyor; inserting a changing frame, with an external lifting apparatus, between the upper run and the lower run or between the lower run and the ground surface and picking up an idler roller to be replaced with a pick-up means of the changing frame; leading the changing frame, together with the idler roller, out of an area between the upper run and lower run or between the lower run and ground surface and in a reverse manner, inserting a new idler roller into mounts of the idler roller to be replaced; and lifting the subframe by an external lifting apparatus, to detach the subframe from the support frame and lowering the web belt.

2. A process in accordance with claim 1, wherein a plurality of idler rollers of an idler roller station are replaced by multiple repetition of steps of: inserting a changing frame, with an external lifting apparatus, between the upper run and the lower run or between the lower run and the ground surface and picking up an idler roller to be replaced with a pick-up means of the changing frame; leading the changing frame, together with the idler roller, out of an area between the upper run and lower run or between the lower run and ground surface and in a reverse manner, inserting a new idler roller into mounts of the idler roller to be replaced; and lifting the subframe by an external lifting apparatus, to detach the subframe from the support frame and lowering the web belt.

3. A process in accordance with claim 1, wherein the subframe is set down on the support frame or hung on the support frame and is detached from the lifting apparatus, and the changing frame is manipulated with the same lifting apparatus.

4. A process in accordance with claim 1, wherein prior to the picking up of the changing frame with the external lifting apparatus, an anchoring eyelet, which is displaceable in parallel to and at right angles to the direction of conveying of the web belt, is adjusted, such that the lifting apparatus grasps vertically above a center of gravity of the changing frame with a picked-up idler roller.

5. A process for replacing individual idler rollers of a belt conveyor, the process comprising the steps of: providing a device comprising a subframe for lifting a web belt in an upper run and a lower run, the subframe comprising an upper subframe portion, a lower subframe portion and a connecting subframe portion extending between the upper subframe portion and the lower subframe portion, a changing frame adapted structurally to idler roller stations of the belt conveyor in the upper run and lower run and a movable service vehicle comprising an external lifting apparatus; inserting the subframe and the changing frame between the upper run and the lower run or between the lower run and ground surface and the subframe, at least a portion of the upper subframe portion being located at a position above the web belt when the subframe is inserted between the upper run and the lower run or between the lower run and the ground surface; lifting the changing frame via the external lifting apparatus of the service vehicle after inserting the changing frame between the upper run and the lower run or between the lower run and ground surface and the subframe.

6. A process in accordance with claim 5, wherein the changing frame is provided at a top with anchoring eyelets, the changing frame being picked up above a center of gravity by the external lifting apparatus of the service vehicle using a rope engaging the anchoring eyelet.

7. A process in accordance with claim 5, wherein the subframe has a web pick up means for picking up the web belt in an entire width while maintaining a trough shape as well as support frame engagement means for setting the subframe down on or hanging the subframe on a support frame of the conveyor.

8. A process in accordance with claim 7, wherein the subframe has a plurality of supports, which are adjustable and lockable in a slope position, for picking up the web belt while maintaining the trough shape.

9. A process in accordance with claim 5, wherein the subframe has at least two collapsible brackets or hooks for setting down the subframe on or hanging the subframe on the support frame of the belt conveyor.

10. A process in accordance with claim 8, wherein the subframe has a c-shaped design, the subframe having an upper carrier piece and a lower carrier piece, whereby at least one anchoring eyelet is arranged at the upper carrier piece, the supports are arranged at the lower carrier piece at a top, and the brackets or hooks are arranged at the bottom and/or end.

11. A process in accordance with claim 5, further comprising providing another changing frame to provide changing frames that are each adapted structurally to idler roller stations in the upper run and lower run and have pivotable idler roller pick-ups designed as straight carriers with movable claws to form means for picking up the idler rollers.

12. A process in accordance with claim 11, wherein the idler roller pick-ups are pivotable against the changing frames in bolt connections.

13. A process in accordance with claim 5, further comprising providing an anchoring eyelet displaceable in parallel to and at right angles to a direction of conveying of the web belt, the anchoring eyelet being arranged at a top of the changing frame.

14. A process in accordance with claim 5, wherein for idler roller stations of the lower run, the changing frame is at least one of two changing frame variants, which can each be inserted from one side between the lower run and the ground surface, without colliding with the idler roller stations of the upper run.

15. A process in accordance with claim 10, wherein at least a portion of the upper carrier piece is arranged above at least a portion of the web belt when the subframe is inserted between the upper run and the lower run or between the lower run and the ground surface.

16. A process in accordance with claim 10, wherein the at least one anchoring eyelet is arranged at a position above at least a portion of the web belt when the subframe is inserted between the upper run and the lower run or between the lower run and the ground surface.

17. A process in accordance with claim 10, wherein the subframe comprises a vertically extending carrier piece, the upper carrier piece being connected to the lower carrier piece via the vertically extending carrier piece.

18. A process in accordance with claim 17, wherein the vertically extending carrier piece has a height that is greater than a height of the web belt.

19. A process in accordance with claim 17, wherein the vertically extending piece extends in a direction transverse to a conveying direction of the web belt.

20. A process for replacing individual idler rollers of a belt conveyor, the process comprising the steps of: providing a device comprising a subframe for lifting a web belt in an upper run and a lower run; providing a changing frame adapted structurally to idler roller stations of the belt conveyor in the upper run and lower run; providing a service vehicle which is conveyable and equipped with an external lifting apparatus; inserting the subframe and the changing frame between the upper run and the lower run or between the lower run and ground surface and the subframe; and picking up the changing frame via the external lifting apparatus of the service vehicle after inserting the subframe and the changing frame between the upper run and the lower run or between the lower run and ground surface and the subframe.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the drawings:

(2) FIG. 1a is a perspective view showing a subframe for lifting the web belt in the upper run in the starting position;

(3) FIG. 1b is a perspective view showing the subframe according to FIG. 1a in the position set down on the support frame of a conveyor system;

(4) FIG. 1c is a perspective view showing the subframe in the position brought into the end position on the support frame of the conveyor system compared to the view according to FIG. 1b;

(5) FIG. 2a is a perspective view showing the changing frame for a replacing device for idler rollers arranged in a troughed manner in the upper run in a perspective view;

(6) FIG. 2b is a perspective view showing the idler roller pick-up of the changing frame according to FIG. 2a with opened claws and the two perforated plates as a detail;

(7) FIG. 2c is a perspective view showing a picked-up idler roller;

(8) FIG. 2d is a perspective view showing the changing frame brought into position next to the subframe in the picking up of a worn-out idler roller or after the setting down of a new idler roller with opened claws;

(9) FIG. 3a is a side view showing the subframe for lifting the web belt in the lower run in the starting position;

(10) FIG. 3b is a side view showing the subframe brought into function at the support frame of the belt system compared to FIG. 3a;

(11) FIG. 4a is a perspective view showing the two changing frames for the idler rollers in the lower run as a detail view;

(12) FIG. 4b is a perspective view showing the use of one of the two changing frames when picking up an idler roller to be removed in the lower run; and

(13) FIG. 4c is a perspective view showing the pivoting out of the picked-up old idler roller according to FIG. 4b or the pivoting in of a new idler roller.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

(14) Referring to the drawings in particular, because of the different number, size and arrangement of the idler rollers of a belt conveyor in the upper run and in the lower run, a replacing device for the idler rollers is to be adapted separately to the replacement in the upper run and in the lower run. Therefore, two dividing devices are provided, each of which is comprised of a subframe for lifting the web belt 7 and a changing frame for the idler rollers. All four frames of the device are brought into function at the respective idler roller station by means of a service unit that is conveyable and is provided with a lifting apparatus. Personnel can travel with this service vehicle along the belt conveyor of a conveyor system to a certain idler roller station and bring the subframe into position as well as perform the replacement of defective idler rollers with the suspended changing frame. Such service vehicles equipped with a lifting apparatus are known, for example, from the publications according to DD 148 501 A1 and DE 2 342 000 A1. They are used there for replacing idler roller girlands.

(15) For replacing the idler rollers 51, 52, 53, which are arranged in a troughed manner in the upper run, of the idler roller station 5 of a belt conveyor, a subframe 1 according to FIGS. 1a through 1c is provided for lifting the web belt 7 and a changing frame 2 according to FIGS. 2a through 2d for replacing defective or worn-out idler rollers 51.sup.old, 52.sup.old and/or 53.sup.old with new functional idler rollers 51.sup.new, 52.sup.new and/or 53.sup.new. In the view in the drawing, the superscripts .sup.old and .sup.new are omitted, since in the reproduction of a respective situation it may involve both the removal of a defective or worn-out idler roller and the installation of a new idler roller 51, 52, 53.

(16) The subframe 1 of the replacing device for idler rollers 51, 52, 53 in the lower run of a belt conveyor for lifting the troughed web belt 7 has a c-shaped design according to FIG. 1b and FIG. 1c. The upper horizontal carrier piece is shorter than the lower horizontal carrier piece and is equipped at the top in the center of gravity with an anchoring eyelet 11 for pick-up by means of a load-pick-up means. On both sides of the lower horizontal carrier piece, this is provided with a collapsible bracket 12, 13 each, by means of which the subframe 1 is set down on the support frame 8 of the belt conveyor in the pivoted state under the web belt 7, as shown in FIG. 1b, after the unfolding of the brackets 12, 13. According to the exemplary embodiment, each idler roller station 5 in the lower run is equipped with three idler rollers 51, 52, 53. The two outer idler rollers 51, 53 are adjusted at an angle of 45 to the lower, middle idler roller 52 for troughing the web belt 7. This angle may, notwithstanding, also be 35, 40 or another number of degrees depending on the design of the belt conveyor.

(17) The lower horizontal carrier of the subframe 1 has two supports 14, 15, which are adjustable in their slope and which, in their starting position, lie on the surface of the carrier, and under the troughed sections of the web belt 7, can be adapted by means of a folding about a bolt connection 16, 17 to the web belt sections having oblique cross sections. The oblique position of the belt supports 14, 15 is adapted to the actual troughing of the belt. The adjustable supports 14, 15 can be locked in their oblique positions by means of struts 18, 19 arranged in an articulated manner and thus can form a construction which has a stable cross section. Consequently, the subframe 1 for lifting the web belt 7 in the upper run can be used in the troughed form in order to release the idler rollers 51.sup.old, 52.sup.old and 53.sup.old of the idler roller station 5 located there and to make it possible to remove the rollers.

(18) For lifting the web belt 7 in the upper run of a belt conveyor, the subframe 1 is picked up by a service vehicle equipped with a crane at the site in question next to the idler roller station 5 with the defective or worn-out idler roller 51.sup.old, 52.sup.old and 53.sup.old and is inserted on site from the side in the clearance between the upper edge of the support frame 8 of the belt conveyor and the web belt 7 in the upper run and, as already described above, is then set down on both sides on the upper edge of the support frame 8. This position is shown in the drawing according to FIG. 1b. Then, the two supports 14, 15 are folded up in a mirror-image manner. Subsequently, the two brackets 12, 13 are pivoted downwards after the lifting of the web belt 7 due to lifting by the subframe 1 and overlying web belt 7 with the lifting apparatus of the service vehicle, such that they now lie on the upper edge of the support frame 8. The three idler rollers 51.sup.old, 52.sup.old and 53.sup.old of an idler roller station 5 are now exposed. FIG. 1c shows this position in the end position of the subframe 1.

(19) FIG. 2a shows the changing frame 2 for removing either a defective or worn-out idler roller 51.sup.old, 52.sup.old and/or 53.sup.old and for inserting one or more new functional idler rollers 51.sup.new, 52.sup.new or 53.sup.new. The drawn arrows show the movement possibilities of the respective individual parts or modules towards one another. In the adjusted end position, these parts or modules can then be fixed to one another. The changing frame 2 consists of a c-shaped carrier 2, at whose lower horizontal carrier piece an idler roller pick-up 22, pivotable in parallel to the direction of conveying, with claws 23, 24 grasping at the axes of the worn-out and new idler rollers 51, 52 and 53, can be selectively brought manually into functional connection or detached again with the respective idler roller axis. Each of these two claws 23, 24 consists of a lower recess for the idler roller pick-up in the area of their axes and a pivotable locking mechanism, such that the idler rollers 51, 52 or 53 are held securely during the replacing movements. For adapting the claws 23, 24 to the respective length of an idler roller 51, 52 or 53 the claws 23, 24 can be displaced along the idler roller pick-up 22 and then fastened with screws in the end position. This may be necessary wherever the middle roller 52 of an idler roller station 5 is shorter than the two outer idler rollers 51, 53 arranged in a troughed manner. Idler roller pick-up 22 can be brought manually into the desired oblique position and then be adjusted by means of a bolt and two perforated plates 25, 26 provided with holes. Here, one perforated plate 25 is fastened to the pivotable idler roller pick-up 22 and the other perforated plate 26 is fastened to the carrier 21. This detail is shown in the drawing according to FIG. 2b. FIG. 2c shows the picking up of an idler roller 51, 52 or 53 with closed claws 23, 24. The lever shown at the upper half of the movable claw is provided for manual actuation for opening and closing.

(20) At its upper horizontal carrier piece, the changing frame 2 is provided with a supporting eyelet 27, which can be longitudinally displaced along the carrier piece and can be fixed in the end position. Consequently, the changing frame 2, in its center of gravity or in the center of gravity formed with the respective idler roller 51, 52 or 53, can be picked up above this center of gravity by the load-pick-up means and held in the desired position.

(21) FIG. 2d shows the arrangement of the subframe 1 and of the changing frame 2 during use at the belt conveyor during the replacement of idler rollers. The picking up of a worn-out idler roller 51.sup.old by means of the changing frame 2, with still opened claws 23, 24, brought into position next to the subframe 1 is also shown there. The same graphical representation also results after inserting and setting down a new idler roller 51.sup.new. Since the middle idler roller 52 is more narrow than the outer idler rollers 51, 53, the distance of the claws 23, 24 grasping at the idler roller axes to one another for adapting to the idler roller pick-up 22 is designed as adjustable.

(22) In order to be able to lift the conveyor belt 7 for replacing defective idler rollers 61.sup.old, 62.sup.old of the idler roller stations 6 in the lower run, a subframe 3, which is u-shaped in the side view, is provided according to FIGS. 3a and 3b. It consists of a lower horizontal, middle carrier piece 31, designed as a square hollow profile, in which displacing carriers 32, 33, which are provided with hooks 34, 35, are arranged in a longitudinally displaceable/telescopic manner on both sides from outside. The carrier piece 31 is provided above with a belt support 39. The subframe 3 is pushed into the position according to FIG. 3a laterally under the conveyor belt 7 in the lower run, then lifted by means of the lifting apparatus arranged on the service vehicle via the two anchoring eyelets 36, 37 arranged at the carrier piece 31 via wire cables or a different load-pick-up means, pushed together and brought into the position shown in FIG. 3b. With its hooks 34, 35, the subframe 3 hangs on the outer longitudinal supports of the support frame 8 of the conveyor belt system. It lifts the conveyor belt 7 with its belt support 39, such that the defective or worn-out idler rollers 61.sup.old, 62.sup.old are exposed.

(23) The belt support 39 can be beveled upwards in a v-shaped manner at its upper support surface from the center and thus can be adapted to the position of the idler rollers 61, 62 of the idler roller station 6 in the lower run.

(24) After the conveyor belt 7 has been lifted by using the subframe 3 together with a lifting apparatus and is held in the lifted position, the defective or worn-out idler rollers 61.sup.old and/or 62.sup.old can be replaced. For this, similar for the upper run, a changing frame 4, which is c-shaped, in principle, is in turn provided, with which the detached idler roller 61.sup.old and/or 62.sup.old of the idler roller station 6 can be picked up, lifted and pivoted laterally out of the area of the belt system, before a new idler roller 61.sup.new and/or 62.sup.new, respectively, can be mounted in the reverse sequence.

(25) However, the different distances of the idler roller stations 5, 6 in the upper run and in the lower run are to be taken into account in the structural design of such a changing frame 4. Since the web belt 7, in the upper run, is additionally loaded by the conveyed goods and, in the lower run, during the return is empty and thus is only loaded by the belts net weight, the distances of the idler roller stations 6 to one another in the lower run may be greater than the distances of idler roller stations 5 to one another in the upper run. These different distances of the idler roller stations 5, 6 are shown in the drawing according to FIGS. 1b and 1c. In order to prevent collisions between upper run idler roller stations and lower run idler roller changing frames, two changing frames 4a and 4b are provided according to FIG. 4a. Both changing frames 4a and 4b consist of an, in principle, c-shaped carrier 41a and 41b. An anchoring eyelet 42a, 42b is arranged in a longitudinally displaceable and lockable manner at the top in the horizontal carrier sections. The lower horizontal carrier sections are equipped with a pivotable idler roller pick-up 43a, 43b. These idler roller pick-ups 43a, 43b are, like the idler roller pick-ups 22 for the changing frames 2, provided with claws 44a, 44b for picking up the idler rollers 61.sup.old, 62.sup.old, and 61.sup.new, 62.sup.new. The movement or displacing directions of individual parts or modules towards one another are shown by arrows in the drawing. According to FIGS. 4a and 4b, both changing frames 4a and 4b have, on the outside, horizontal sections 45a, 45b, which are designed differently from one another, by means of which the changing frames 4a and 4b are guided laterally about individual parts of the support frame 8 of the conveyor system or about idler roller stations 5 of the upper run. These sections 45a, 45b are, in practice, adapted to the respective conveyor system and are therefore do not have to be absolutely embodied with the details disclosed in the exemplary embodiment.

(26) For replacing worn-out/defective idler rollers 61.sup.old and/or 62.sup.old with new idler rollers 61.sup.new and/or 62.sup.new, the suitable changing frame 4a or 4b is selected depending on the location at the belt conveyor. The drawing according to FIG. 4b shows the picking up of an idler roller 61.sup.old in the lower run to be removed and the drawing according to FIG. 4c shows the pivoting out of this picked-up idler roller 61.sup.old. This idler roller 61.sup.old is discarded and a new idler roller 61.sup.new is picked up. The insertion of the new idler roller 61.sup.new takes place in the reverse sequence.

(27) Only two workers are needed for replacing the idler rollers with such a device: One worker removes and installs the idler rollers by means of the device, the second worker operates the service vehicle equipped with a crane.

(28) As an alternative, the device may be used in an adapted form also for replacing idler rollers in idler roller stations for the upper run, which are each equipped with five idler rollers arranged in a trough shape. An adaptation of the changing frame for a different number and arrangement of the idler rollers of an idler roller station for the lower run is also possible.

(29) While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.

REFERENCE NUMBERS

(30) 1 Subframe (upper run) 11 Anchoring eyelet 12 Pivotable bracket 13 Pivotable bracket 14 Oblique support for web belt 15 Oblique support for web belt 16 Bolt connection 17 Bolt connection 18 Strut 19 Strut 2 Changing frame (upper run) 21 c-shaped carrier 22 Idler roller pick-up 23 Claw for idler roller pick-up 24 Claw for idler roller pick-up 25 Perforated plate 26 Perforated plate 27 Anchoring eyelet 3 Subframe (lower run) 31 Carrier piece 32 Displacing carrier 33 Displacing carrier 34 Hook 35 Hook 36 Anchoring eyelet 37 Anchoring eyelet 39 Belt support 4 Changing frame (lower run) 4a Changing frame according to variant a 41a c-shaped carrier 42a Anchoring eyelet 43a Idler roller pick-up 44a Claws 45b Sections 4b Changing frame according to variant b 41b c-shaped carrier 42b Anchoring eyelet 43b Idler roller pick-up 44b Claws 45b Sections 5 Idler roller station, upper run 51 Idler roller on the right 52 Idler roller in the middle 53 Idler roller on the left 6 Idler roller station, lower run 61 Idler roller on the left 62 Idler roller on the right 7 Web belt 8 Support frame of the belt conveyor/conveyor system