DEVICE OR TOOL FOR GRIPPING A LINER TO REMOVE SAME FROM AND INSTALL SAME IN THE SHELL OF A MILL, METHOD FOR INSTALLING A LINER AND METHOD FOR REMOVING A LINER

Abstract

The invention relates to a device or tool (1) for gripping a liner in order to carry out a method of removing same from, and installing same in, the shell of a mill, which comprises a rigid structure or frame (2) forming a support for containing the components needed for the operation thereof, a coupling element (6) that allows the device to be secured or disposed on at least one end of a manipulation device, such as a robotic manipulator, comprises at least one claw or pincer (7) for holding at least one bolt by the head, the tool being designed to allow the adjustment of the relative position thereof in order to align the pincers to the positions of the holes of each liner, the at least one pincer (7) having a configuration allowing said claws to open and close so as to adjust the size thereof to the size of the bolt being gripped, wherein the at least one pincer or claw (7) has at least one sensor, thereby enabling mill liners to be installed and removed, the tool being based on the fastening elements that hold the liners in position.

Claims

1. A device or tool (1) for gripping a liner to remove same from, and install same in, the shell of a mill, CHARACTERISED in that it comprises a rigid structure or frame (2) forming a support for containing the components needed for the operation thereof, a coupling element (6) that allows the device to be secured or disposed on at least one end of a manipulation device, comprises at least one claw or pincer (7) for holding at least one bolt by the head, the tool being designed to allow the adjustment of the relative position thereof in order to align the pincers to the positions of the holes of each liner, the at least one pincer (7) having a configuration allowing said claws to open and close so as to adjust the size thereof to the size of the bolt being gripped, wherein the at least one pincer or claw (7) has at least one sensor which allows determining the effective distance of the pincers (7) with respect to one another and to the frame, which allows verifying whether the claw (7) is in effect open or closed, which allows verifying whether or not the bolt is in position inside the claw, and which allows verifying whether the bolt is in the correct position or axially or radially shifted in an incorrect position.

2. The device or tool (1) for gripping a liner to remove same from, and install same in, the shell of a mill according to claim 1, CHARACTERISED in that the rigid structure or frame (2) comprises a base (3) defining the front face and side walls (4) surrounding the entire base, forming a containing support and a support plate (5) having a coupling element (6), defining the rear face of the device or tool.

3. The device or tool (1) for gripping a liner to remove same from, and install same in, the shell of a mill according to claim 1 CHARACTERISED in that the at least one claw or pincer (7) is disposed in the frame (2) in such a manner that at least one opening (8) of the base (3) is exposed.

4. The device or tool (1) for gripping a liner to remove same from, and install same in, the shell of a mill according to claim 1, CHARACTERISED in that the at least one claw or pincer (7) the adjustment of the relative position thereof can be performed interchangeably by means of mechanical screw actuation, rack and pinion, or else a hydraulic or electric linear actuator.

5. The device or tool (1) for gripping a liner to remove same from, and install same in, the shell of a mill according to claim 1 CHARACTERISED in that the at least one pincer or claw (7) has at least one sensor, such as at least one position sensor (10), at least one claw sensor (11), at least one bolt sensor (12), and/or at least one alignment sensor (13).

6. The device or tool (1) for gripping a liner to remove same from, and install same in, the shell of a mill according to claim 1 CHARACTERISED in that it further comprises a control system which allows operating and controlling said device, having the function of providing power and controlling the device in communication with the manipulator to which it is attached, furthermore having monitoring controls, having at least one switchgear or SG, control panel or CP, control cabinets, position detection panel PDP and human-machine interface or HMI, hydraulic installation, inductive sensors, encoder, among other control means.

7. The device or tool (1) for gripping a liner to remove same from, and install same in, the shell of a mill according to claims claim 1 CHARACTERISED in that it further comprises detection means for detecting the position of the liner configured by at least one machine vision system which is based on machine vision techniques by means of using laser triangulation cameras (L).

8. The device or tool (1) for gripping a liner to remove same from, and install same in, the shell of a mill according to claim 1 CHARACTERISED in that it further comprises an auxiliary system consisting of support arms or holding claws which allow the liner to be held in position.

9. A method for installing a liner by means of using at least one device or tool (1) for gripping liners, CHARACTERISED in that it starts with the command which is made through a computer of a control system in such a manner that the device receives information about the liner to be installed and the disposition of the bolts thereof, which is recorded in the computer, with this command the manipulator, in which said device (1) is installed, moves the device (1) to the position of at least one bolt feeder (14), the distance between the claws (7) which may be comprised in the device is adjusted so as to coincide with the distance between the bolts, the bolts are introduced one-by-one in the different claws (7) which may be comprised in the device (1), then through the detection of at least one sensor (10, 11, 12, 13) the correct position between the claws (7) comprised in the device is detected and verified, and said sensor also allows detecting the bolt and verifying that it is in the correct position, commanding the closure of the claw (7) for holding the bolt, the manipulator continues to feed the other claws (7) with bolts according to the type of liner that will be installed, in such a manner that once all the required claws (7) are provided with bolts, the manipulator shifts out of the bolt feeding area and is disposed for grabbing the liner in the area of a liner feeder, the manipulator moves the device (1) for gripping with bolts secured in the claws and grabs the liner by means of inserting these bolts through the orifices of the liner, and positions same in the specific location on the surface of the shell of the mill.

10. The method for installing a liner according to claim 9, CHARACTERISED in that the manipulator then brings the liner to its installation position, moves the bolts held in the claws (7) of the device (1) closer to their final position, aligning same with the orifices of the mill, introducing the bolts in said orifices causing the threaded opposite end of said bolts to be exposed on the external side of the mill, thereby positioning the liner in the position initially commanded for the final location thereof.

11. The method for installing a liner according to claim 9 CHARACTERISED in that nuts and washers are furthermore installed or on the outside of the mill, in such a manner that once the nuts are installed, the claw (7) supporting the bolt receives information to loosen it, and this is successively performed with the rest of the bolts and their respective holding claws until the device is free of the task, with the liner thus being finally installed in the position initially commanded by the controller.

12. The method for installing a liner according to claim 9 CHARACTERISED in that furthermore in order to ensure the movement position of the liner grabbed by the device (1) for gripping, the computer allows lifting or hoisting the liner in such a manner that it is disposed at an angle which ensures its movement position, where the device (1) for gripping may further comprise an auxiliary system consisting of support arms or holding claws which allow the liner to be held in position.

13. A method for taking out and/or removing a liner by means of using at least one device or tool (1) for gripping liners, CHARACTERISED in that it comprises receiving information about which liner is to be installed and the disposition of the bolts thereof, the distance between claws is adjusted to coincide with the distance between bolts, which is correctly verified and detected by at least one sensor, the manipulator brings the device (1) to the position in which the shafts of the bolts are aligned with the claws or pincers (7), the nuts are loosened one-by-one on the outside of the mill, and the bolts are pushed into the mill, every time the head of a bolt enters the claw (7), the latter detects the presence of this element and proceeds to close, and this is detected and verified by at least one sensor, whereby the holding thereof is achieved, once all the bolts have been released, pushed, and held by the claws (7), the manipulator proceeds to finally detach the liner from the shell of the mill and takes it out of said position to be moved to the liner feeder device which finally removes it from the area together with the bolts.

14. The method for taking out and/or removing a liner according to claim 13, CHARACTERISED in that the device (1) furthermore holds the liner either by means of an auxiliary claw, a lower support, an electromagnet, or else by means of pushing it against the shell.

15. The method for taking out and/or removing a liner according to claim 9, CHARACTERISED in that furthermore in order to ensure the movement position of the liner grabbed by the device (1) for gripping, the computer allows lifting or hoisting the liner in such a manner that it is disposed at an angle which ensures its movement position, wherein the device (1) for gripping may further comprise an auxiliary system consisting of support arms or holding claws which allow the liner to be held in position.

Description

DESCRIPTION OF THE DRAWINGS

[0019] In order to help to better understand the features of the invention according to a preferred practical embodiment thereof, a set of drawings is attached as an integral part of the description in which the invention is depicted in an illustrative and non-limiting manner.

[0020] FIG. 1 corresponds to a side view of tools representing the prior art.

[0021] FIG. 1a corresponds to a side view of the tool or device for manipulating a liner attached to a manipulator, in which a new liner is shown.

[0022] FIG. 1b corresponds to a side view of the tool or device for manipulating a liner attached to a manipulator, in which a used liner is shown.

[0023] FIG. 2 corresponds to a side view of a longitudinal section of the device for manipulating a liner of the present invention.

[0024] FIG. 3 corresponds to a side view of a longitudinal section of the device for manipulating a liner with the claws of the present invention closed.

[0025] FIG. 4 corresponds to a top plan view of the device for manipulating a liner according to the invention.

PREFERRED EMBODIMENT OF THE INVENTION

[0026] The invention relates to a device or tool (1) for gripping a liner to remove same from, and install same in, the shell of a mill, which comprises a rigid structure or frame (2) (FIGS. 1a and 1b), comprising a base (3) defining the front face (see FIG. 4) of the device or tool (1) and side walls (4) surrounding the entire base, forming a support for containing the components needed for the operation thereof. The frame comprises a support plate (5) having a coupling element (6), defining the rear face of the device or tool (1) (FIGS. 2 and 3), that allows the device to be secured or disposed on at least one end of a manipulation device, such as a robotic manipulator with six degrees of freedom.

[0027] The device or tool (1) comprises at least one claw or pincer (7) for holding at least one bolt by the head, disposed in the frame (2) such that at least one opening (8) of the base (3) is exposed. The tool may comprise a plurality of claws or pincers (FIG. 4).

[0028] The at least one claw or pincer (7) has a configuration allowing the adjustment of the relative position thereof in order to align the pincers to the positions of the holes of each liner, which can be performed interchangeably by mechanical screw actuation, rack and pinion, or else a hydraulic or electric linear actuator (9), the latter being illustrated by way of example in FIGS. 2 and 4).

[0029] The shape and configuration of the at least one pincers (7) allow opening and closing said claws so as to adjust the size thereof to the size of the bolt being gripped, such that they are operated to open or close with the force needed for grabbing or releasing a liner bolt, where necessary. The actuation for opening or closing the pincers can be performed interchangeably by means of mechanical screw actuation, gears, or else a hydraulic, pneumatic, or electric linear actuator, as necessary.

[0030] The at least one pincer or claw (7) has at least one sensor (FIGS. 2 and 4), such as at least one position sensor (10), which allows determining the effective distance of the pincers (7) with respect to one another and to the frame, at least one claw sensor (11) which allows verifying whether the claw (7) is in effect open or closed, at least one bolt sensor (12) which allows verifying whether or not the bolt is in position inside the claw, and at least one alignment sensor (13) which allows verifying whether the bolt is in the correct position or axially or radially shifted in an incorrect position.

[0031] The method for installing a liner by means of using the device or tool (1) for gripping liners starts with the command which is made through a computer of a control system such that the device receives information about the liner to be installed and the disposition of the bolts thereof, which is recorded in the computer, with this command the manipulator, in which said device (1) for gripping liners is installed, such as preferably an automated robotic manipulator, such as those used by the applicant of the present invention, moves the device (1) to the position of at least one bolt feeder (14), the distance between the claws (7) which may be comprised in the device is adjusted so as to coincide with the distance between the bolts, and this is carried out by means of actuating the at least one mechanical screw actuation means, gears, or else a hydraulic, pneumatic, or electric linear actuator (9), according to the type of liner to be changed according to the command given by the controller, such that in operation the bolts are introduced one-by-one in the different claws (7) which may be comprised in the device (1). Through the detection of at least one sensor (10, 11, 12, 13), the correct position between the claws (7) comprised in the device is detected and verified and said sensor also allows detecting the bolt and verifying that it is in the correct position, commanding the closure of the claw (7) for holding the bolt. The manipulator continues to feed the other claws (7) with bolts according to the type of liner that will be installed, in such a manner that once all the required claws (7) are required with bolts, the manipulator shifts out of the bolt feeding area and is disposed for grabbing the liner in the area of a liner feeder, the manipulator moves the device (1) for gripping with bolts secured in the claws and grabs the liner by means of inserting these bolts through the orifices of the liner, and positions same in the specific location on the surface of the shell of the mill.

[0032] In an alternative form of the invention and in order to ensure the movement position of the liner grabbed by the device (1) for gripping, the computer allows lifting or hoisting the liner such that it is disposed at an angle which ensures its movement position, where the device (1) for gripping may further comprise an auxiliary system consisting of support arms or holding claws which allow the liner to be held in position.

[0033] The manipulator then brings the liner to its installation position, which is clearly identified and commanded by the controller, moves the bolts held in the claws (7) of the device (1) closer to their final position, aligning same with the orifices of the mill, introducing the bolts in said orifices causing the threaded opposite end of said bolts to be exposed on the external side of the mill, thereby positioning the liner in the position initially commanded for the final placement thereof. Nuts and washers are then installed or on the outside of the mill, in such a manner that once the nuts are installed, the claw (7) supporting the bolt receives information to loosen it, and this is successively performed with the rest of the bolts and their respective holding claws until the device is free of the task, with the liner thus being finally installed in the position initially commanded by the controller.

[0034] The process for taking out and/or removing a liner comprises receiving information about which liner is to be installed and the disposition of the bolts thereof, the distance between claws is adjusted to coincide with the distance between bolts, which is correctly verified and detected by at least one sensor, the manipulator brings the device (1) to the position in which the shafts of the bolts are aligned with the claws or pincers (7), the device (1) holds the liner either by means of an auxiliary claw, a lower support, an electromagnet, or else by means of pushing it against the shell, the nuts are loosened one-by-one on the outside of the mill, and the bolts are pushed into the mill, every time the head of a bolt enters the claw (7), the latter detects the presence of this element and proceeds to close, and this is detected and verified by at least one sensor, whereby the holding thereof is achieved. Once all the bolts have been released, pushed, and held by the claws (7), the manipulator proceeds to finally detach the liner from the shell of the mill and takes it out of said position, to be moved to the liner feeder device which finally removes it from the area together with the bolts.

[0035] The device or tool (1) for gripping a liner to remove same from, and install same in, the shell of a mill may comprise a control system which allows operating and controlling said device for changing the liners of the present invention, having the function of providing power and controlling the device in communication with the manipulator to which it is attached, furthermore having monitoring controls. The control system has at least one switchgear or SG, control panel or CP, control cabinets, position detection panel PDP and human-machine interface or HMI, hydraulic installation, inductive sensors, encoder, among other control means.

[0036] In one embodiment of the invention, the device (1) for gripping liners may comprise detection means for detecting the position of the liner configured by at least one machine vision system which is based on machine vision techniques by means of using laser triangulation cameras (L) through which scanning of the mantle of the inner surface of the mill is performed to determine the position in which the liner should be inserted or from which it should be removed, said machine vision system being capable of delivering the distance and angle of the succession of holes, so that the manipulator can make a decision concerning insertion and approach.

[0037] The configuration of the device or tool (1) for gripping a liner to remove same from, and install same in, the shell of a mill of the present invention allows mill liners to be installed and removed, the tool being based on the fastening elements that hold the liners in position, and this is achieved by holding the bolts at the exact distance at which they will be installed, which in turn corresponds to the same distance of the perforations of the liners; in this manner, the tool can lift the liner by introducing the bolts inside same and moving it to its installation position in a safe and accurate manner without the need for human interaction in the process and without regard to the deformations that the liners may experience. When removing the liner, the device (1) is positioned at the exact distance where there are arranged fastening elements which, when removed, are held by the device (1), generating the necessary interference to be able to lift the worn liner without having to throw the liner on the floor of the mill. Therefore, the liner is but an additional element among the components to be held, in addition to preventing the liner from falling to the floor at the moment of removing it, along with the elimination of the need for staff in the process.

[0038] Although the configuration of the device or tool (1) for gripping a liner to remove same from, and install same in, the shell of a mill herein described constitutes a preferred inclusion of this invention, it must be understood that the invention is not limited to this specific form of the system for changing the liner, given that changes can be made therein without departing from the scope of the invention defined in the attached claims.