The present invention relates to the mining industry. The invention particularly concerns a device and a method at rotating magazines for e.g. rock drilling rods or rock bolts.

BACKGROUND

Drills are often used in mines or other work sites to drill holes into the bedrock. Usually mobile rigs are used, which carry rock drilling equipment arranged for this purpose. A feed beam for a rock drilling machine may therefore be arranged on the rig.

In certain cases the hole in the rock may need to be drilled deeper than the length of the individual rock drilling rod. In such cases, two or more rods may be connected such that an extended rod is acquired. For example, a first rod may be used to drill a hole in the rock, the depth of which corresponds to the length of the rod. A second rod may thereafter be connected to the part of the first rod which sticks out of the rock, after which both rods are drilled further into the rock. This method may be repeated until a drill hole having a desired depth is achieved.

In order to be able to perform this type of drilling in an efficient manner, several rods need to be transported along on the rig. Usually a magazine in which rods can be stored is used for this purpose. The magazine may for instance via a frame be arranged to the feed beam of the rock drilling machine. A type of magazine used for this purpose is a rotating magazine having a surrounding structure arranged around the magazine to prevent drill rods from falling out of the magazine. An opening in the surrounding structure allows a picking arm to remove rods from or place rods into the magazine.

The magazine having rods and a picking arm may be both bulky and heavy, as well as require a lot of complex regulation in order to function efficiently. Furthermore, the equipment must be able to handle the stressful environment which often prevail where the equipment is used, e.g. in mines.

CN 104405308 describes a device comprising two picking arms arranged to remove rods from or place rods into a magazine. The device is adapted for rock drilling applications. EP3147448 describes a device comprising a picking arm arranged to remove rods from or place rods into a magazine. The picking arm is arranged to be able to collect rods both from the magazine and an external source. The magazine may comprise mechanical stops for the picking arm such that no sensors need to be used for positioning the picking arm.

SE469186 describes a magazine for rods adapted to be used in rock drilling applications. The magazine consists of two rod holding discs built up of four segments which are individually detachably connected to a rotational axis.

SE8305847-9 describes a rotating magazine for rock drilling rods or rock bolts where two rings are arranged around a rod holder in order to prevent the rods from falling out of the rod holder. The rings have openings through which a rod may be removed from or be placed into the magazine. For this purpose a picking arm or a plier is used. When the plier is in a waiting position it may function as a gate in order to prevent a rod placed right at the openings of the rings to fall out of the rod holder.

In common for the above described devices is that they comprise several components which interact. The described devices are therefore relatively complex.

SUMMARY

An object of the present invention is to achieve a device at rock drilling which is compact, resistant to harsh and demanding environments and which is able to reduce the number of stops in operation and thereby the idling time. Alternatively, to achieve an alternative to known solutions within the technical field.

The object is achieved according to a first aspect of the invention by a rod feeding device comprising a frame and a rotatable magazine arranged on the frame and arranged with a plurality of grooves around its periphery in which rods may be placed. The rod feeding device further comprises at least one securing arrangement which ensures that the rods may only leave the magazine at an access position of the securing arrangement. The rod feeding device further comprises at least one movable picking arm arranged to be able to be moved to a first position where the picking arm via the access position can place rods into and remove rods from the magazine. The device also comprises a rotatable magazine mover. The magazine is arranged to be able to be locked to the magazine mover. The magazine mover can rotate the magazine when they are locked to each other and rotate relatively to the magazine when they are not locked to each other. The magazine mover furthermore comprises a rod gripping arrangement which secures a rod in its groove in the magazine when the magazine mover is positioned in a rod gripping position.

Since the magazine mover can prevent rods from falling out of the magazine during rotation of the magazine a rod feeding device which is reliable in operation and with less risk of failure during operation is achieved. Since the magazine mover may be disconnected from the magazine and rotate relative to the magazine when they are not connected, the magazine mover is both able to secure rods but also rotate away from the magazine in order for the picking arm to be able to remove rods from or place rods into the magazine. Furthermore, since the magazine mover and the magazine may be locked to each other the magazine mover can rotate the magazine. Thereby there is no need for components which rotate the magazine separately. By requiring fewer components the rod feeding device will be less complex which reduces the risk of a component breaking.

Consequently, a compact rod feeding device which by securing the rods during operation and reducing the number of components is adapted to withstand a tough working environment with few breaks during operation is achieved.

The above mentioned object is also achieved according to a second aspect of the invention by a method for removing rods from the rod feeding device. The method comprises the steps of rotating the magazine in a first direction such that a groove in the magazine containing a first rod is positioned in an access position where the rotation of the magazine is performed by the magazine mover in such a way that the first rod is secured in its position in the magazine during the displacement. The method furthermore comprises the steps of removing the first rod from the magazine, where the removing is performed by the picking arm in such a way that the first rod is secured by the picking arm during the removing method. The above mentioned object is also achieved according to a third aspect of the invention by a method of placing rods in the rod feeding device. The method comprises the steps of collecting a rod outside of the magazine with the picking arm and placing the rod in a groove in the magazine which is positioned in the access position. The method furthermore comprises the step of rotating the magazine in a second direction until the rod is secured by the securing arrangement, where the rotation is performed by the magazine mover in such a way that the rod is secured in its position in the magazine during the transportation.

By securing the rod during the entire removing method and the entire placing method the number of operational stops are reduced, since the rod does not risk falling out or being positioned in a slanted position when the method is performed.

Furthermore, the removing of rods from the rod feeding device as well as the placing of rods in or into the rod feeding device is achieved using few separate components, which minimizes the risk of component failure. Thus, a removing method and a placing method is achieved which methods are adapted to be able to be performed in tough

environments where the number of operational stops are reduced.

Consequently, there is achieved a method for removing rods from the rod feeding device in a secure way and a method for placing rods in the rod feeding device in a secure way, where the methods are adapted for tough environments and minimizes the risk of failure during operation. The above described methods thereby reduce the number of operational stops.

BRIEF DESCRIPTION OF THE DRAWINGS

Additional objects and advantages to, as well as features of, the invention will be apparent from the following detailed description of one or several embodiments provided with reference to the accompanying drawings, in which:

Fig. 1 shows a rod feeding device in perspective view in a first direction.

Fig. 2 shows the rod feeding device in perspective view in a second direction, opposite to the first direction.

Fig. 3 shows the rod feeding device in a side view. Fig. 4a shows a magazine mover in perspective view in a first direction.

Fig. 4b shows the magazine mover in perspective view in a second direction, opposite to the first direction.

Fig. 5 shows the rod feeding device in a cross-section view.

Fig. 6 schematically shows a rod magazine and a picking arm in two positions in a cross- section view.

Fig. 7 shows a flow chart showing a method for removing rods from the rod feeding device.

Fig. 8 shows a flow chart showing a method for placing rods in the rod feeding device.

DETAILED DESCRIPTION

The invention herein will now be described in more detail below with reference to the accompanying drawings, in which example embodiments are shown. The invention should not be construed as limited by the disclosed examples of embodiments, instead it is defined by the appended claims. Like numbers in the figures refer to like elements throughout.

Figure 1 and 2 illustrate an exemplifying rod feeding device 1 for e.g. a rock drilling machine. The rod feeding device 1 comprises a frame 3, a rotatable magazine mover 15 and a rotatable magazine 5 arranged on the frame 3 and arranged with a plurality of grooves 7 around its periphery in which rods may be placed. The magazine 5 may be arranged with a circular or semi-circular plate with grooves 7 arranged around its periphery at a constant radial distance from the axis of rotation of the magazine 5. The magazine 5 is arranged to be able to be locked to the magazine mover 15. Thereby, the magazine mover 15 is able to rotate the magazine 5 when they are locked to each other and rotate relative to the magazine 5 when they are not locked to each other.

According to some embodiments the rod feeding device 1 comprises a shaft 19 rotatable arranged to two rotation bearings arranged in the frame 3, wherein the magazine 5 is fixedly arranged on the shaft 19 and the magazine mover 15 is rotatable arranged on the shaft 19.

By arranging the shaft 19 rotatable to the frame 3, the shaft may rotate relative to the frame 3. The magazine 5 which is fixedly connected to the shaft 19 will rotate when the shaft 19 rotates. Since the magazine mover 15 is rotatable arranged on the shaft 19, the magazine mover 15 is able to rotate both relative to the shaft 19 and the magazine 5. When the magazine 5 is locked to the magazine mover 15, a rotation of the magazine mover 15 will lead to a rotation of both the magazine 5 and the shaft 19.

The magazine 5 may according to some embodiments consist of two plate- shaped magazine elements 5a, 5b having grooves 7 arranged at a constant radial distance from the shaft 19 and distributed across the periphery of the magazine elements 5a, 5b, wherein the magazine elements 5a, 5b are fixedly arranged to the shaft 19 at a distance from each other.

By providing the magazine 5 with two magazine elements 5a, 5b a more stable support for the rods as well as a lighter construction is achieved since only two plates are needed in order to carry the rods. Furthermore, additional components may be placed between the plates. The magazine elements 5a, 5b may be formed as circular or semi-circular plates having grooves 7 for rods around the periphery. The magazine elements 5a, 5b may be placed on a common shaft 19 in such a way that the position of the grooves 7 of the first magazine element 5a around the shaft 19 correspond with the position of the grooves 7 of the second magazine element 5b around the shaft 19.

Thereby the rods may be carried by the two magazine elements 5a, 5b by resting in a groove of both the first 5a and the second 5b magazine element.

The magazine mover 15 is according to some embodiments rotatable arranged on the shaft 19 between the magazine elements 5a, 5b.

By arranging the magazine mover 15 between the magazine elements 5a, 5b, preferably midway between the magazine elements 5a, 5b, a compact shape of the rod feeding device 1 is achieved.

In order to be able to connect the magazine 5 and the magazine mover 15, the rod feeding device 1 may according to some embodiments comprise a first force means 17 fixedly connected to the shaft 19, wherein the first force means 17 comprise a slidable locking element 171 which is arranged to be able to be connected to the magazine mover 15 by sliding in a first axial direction. See for instance figure 3.

The first force means 17 is thus via the shaft 19 arranged in a fixed connection to the magazine 5. The magazine 5 is therefore locked to the magazine mover 15 and they can be rotated together by connecting the locking element 171 of the first force means 17 to the magazine mover 15. For this purpose, the magazine mover 15 may be arranged with holes or openings 23 for the locking element 171 of the first force means 17 to engage with. A preferred embodiment of this connection will be described in more detail below. The magazine 5 is according to some embodiments also arranged to be able to be locked to the frame 3.

In this way it may be ensured that the magazine 5 does not rotate at times when it is not desired. In order to be able to achieve the connection of the magazine 5 and the frame 3, the slidable locking element 171 is according to some embodiments also arranged to be able to be connected to the frame 3 by sliding in a second axial direction. It is also possible to use a second locking element arranged to be able to slide in the second axial direction.

The magazine 5 may thus through the action of the force means 17 be connected to the frame 3 which prevents both the magazine 5 and the shaft 19 from rotating. Holes or openings 21 may e.g. be arranged in the frame 3. The locking elements of the first force means 17 may then engage with these so that the magazine 5 may be locked to the frame 3. A plurality of openings 21 may be arranged in the frame 3. The openings 21 may be arranged on a circle or arc of a circle around the fastening of the shaft 19 in the frame 3. The magazine 5 may thereby be locked to the frame 3 at a plurality of predefined positions around the rotation axis of the magazine 5. In figure 3 the rod feeding device 1 is shown from a viewing direction which is perpendicular to the longitudinal extension of the rod feeding device 1. In figure 3 the magazine 5 is connected to the frame 3 by the slidable locking element 171 having engaged an opening 21 in the frame 3. From the figure it is also clear that the locking element 171 by sliding in the opposite direction (downwards in the figure) may engage openings 23 in the magazine mover and thereby lock the magazine 5 to the magazine mover 15.

The magazine 5 may thus according to some embodiments be connected to the magazine mover 15 or the frame 3, depending on whether the force means 17 is connected to the magazine mover 15 or the frame 3 through the locking element.

A brake may according to some embodiments be arranged to the shaft 19 in order to lock the shaft 19 and thereby the magazine 5 from rotating. The brake may for instance be arranged on the shaft 19 by the rotation bearings.

Thereby it is ensured that the magazine 5 cannot rotate at times when it is not desirable. The brake may be switched on continuously such that a constant breaking force acts on the shaft 19. The magazine mover 15 may then achieve a rotation of the magazine 5 and the shaft 19 by acting on the shaft 19 with a rotation force which exceeds the breaking force of the break. The magazine 5 and the shaft 19 will then be locked by the break when the magazine mover 15 is not connected to the magazine 5. Alternatively, the break may switch off when the magazine 5 is connected to the magazine mover 15. The magazine mover 15 may thereby easily rotate the magazine 5. The break may be switched on again after the rotation has been performed in order to hold the magazine 5 in position.

The locking of the magazine 5 to the frame 3 and the arranging of a break to the shaft 19 are two alternative ways of preventing rotation of the magazine 5 and the shaft 19. These can be implemented separately or in combination.

The force means 17 may for example be a double acting hydraulic cylinder, e.g. a plunger cylinder. The hydraulic cylinder may be arranged with a rod piston 171 which may be slid in two directions. By sliding the rod piston in the first direction the rod piston may engage an opening 23 in the magazine mover 15 and by sliding the rod piston in the second direction the rod piston may engage an opening 21 in the frame 3. Another possible alternative may be that the hydraulic cylinder is arranged with twin rod pistons, one for sliding in each direction.

Other ways of connecting the magazine 5 to the magazine mover 15 are possible, e.g. through radial piston engines or similar.

As is illustrated in figure 1 , 4a and 4b, the rod feeding device 1 may according to some embodiments comprise a second force means 33 arranged to, by controlling in a first direction, achieve a rotation of the magazine mover 15 in a first direction, and by controlling in a second direction, achieve a rotation of the magazine mover 15 in a second direction, opposite of the first direction.

The force means 33 may thus be arranged to the magazine mover 15 in order to rotate the magazine mover around its rotation axis. The force means 33 may, as is illustrated in figure 5, consist of a hydraulic cylinder 331 having a piston rod 333 connected to the magazine mover 15. The magazine mover 15 may comprise an attachment element 35 to which the piston rod 333 is arranged. The attachment element 35 may, as is illustrated in figures 4a and 4b, jut out from the main extension surface of the magazine mover 15. A rotation of the magazine mover 15 around an axis may then be achieved by a linear movement of the piston rod. The hydraulic cylinder 331 may be double acting. The piston rod 333 may then be moved in two directions such that the magazine mover 15 may be made to rotate in both directions around the axis. The force means 33 may alternatively consist of e.g. a worm gear or a radial piston engine, whereby a rotation of the magazine mover 15 may be achieved by these in a known manner.

The rod feeding device 1 further comprise at least one securing arrangement 9 which ensures that the rods may only be moved out of the grooves 7 and leave the magazine at an access position 11 of the securing arrangement 9. The securing arrangement 9 ensures that the rods cannot leave or fall out of the magazine 5 except at the access position 11. This may e.g. be ensured by the mechanical shape of the securing arrangement 9. The securing arrangement 9 may for instance be in the shape of a ring or shaped as a surrounding structure or a hoop arranged at a constant radial distance from the periphery of the magazine. The securing arrangement 9 may further extend partially around the axis of rotation of the magazine 5. The access position 11 may then be the part of the axis of rotation of the magazine 5 which the securing arrangement 9 does not extend around. By rotating the magazine 5 with the rods around the rotation axis of the magazine 5, a rod may thus be rotated to a position where the securing arrangement present an opening, and from that position be picked out of the magazine 5. Depending on how the securing arrangement 9 is shaped, the access position 1 1 may correspond to a plurality of positions of the picking arm 13, i.e. the picking arm 13 may be moved to several different positions but in all of these positions still be considered to be in the access position 11. The securing arrangement 9 may be arranged to the frame 3 and may comprise several rings or surrounding structures. A number of surrounding structures may for example be arranged to a rod or beam which is fixedly secured to the frame 3, as is illustrated in figure 1 and 2. According to a preferred embodiment the securing arrangement 9 may consist of two rings or surrounding structures. Other ways of ensuring that the rods do not leave the magazine 5 are possible, e.g. magnetic or electro-magnetic solutions.

The magazine mover 15 furthermore comprises a rod gripping arrangement 31 which secures a rod in its groove in the magazine 5 when the magazine mover 15 is positioned in a rod gripping position. Figure 4a and 4b show an exemplifying embodiment of the magazine mover 15 seen obliquely from the side 3. The magazine mover 15 may be plate-shaped. The magazine mover may be arranged with a substantially circular cross-section in the normal plane of its rotation axis. The rod gripping position is thus determined by the shapes of the rod gripping arrangement 31 , the magazine mover 15 and the magazine 5, as well as the positions of the rods in the magazine 5. This means that the magazine mover 15 may be in the rod gripping position at the same time as it is in the access position 11 , since the access position 11 is a position relative to the securing

arrangement 9.

The rod gripping arrangement 31 may according to some embodiments be shaped such that when the magazine mover 15 is positioned in the rod gripping position, then the rod gripping arrangement 31 extends at least partially around the periphery of the rod in such a way that it secures the rod in the groove 7 in the magazine 5 in which the rod rests.

The rod gripping arrangement 31 may e.g. consist of a from the main body of the magazine mover 15 protruding part 31 which is shaped with a rod receiving surface which follows the shape of the cross section of the rod, e.g. a bend or curve, such that it may extend at least partially around the periphery of a rod. The rod receiving surface may be distanced from a rod when it is lying in its intended position in the magazine 5 but come into contact with the rod if the rod is about to fall out of the magazine 5. The rod gripping arrangement 31 may according to some embodiments be arranged as a hook or with a U-shape in order to achieve the securing of the rod.

By such an arrangement of the rod gripping arrangement 31 it may be ensured that the rod is secured in the magazine when the rod gripping arrangement 31 is in the rod gripping position.

The rod gripping arrangement 31 is according to some embodiments arranged such that when the magazine mover 15 is positioned such that it is in contact with a rod placed in the magazine 5, the rod gripping arrangement 31 secures the rod in its groove in the magazine 5.

By arranging the magazine mover 15 and the rod gripping arrangement 31 in such a way, there is no need for advanced sensor in order to determine the relative position of the magazine mover 15 and the magazine 5 for the purpose of ensuring that no rods fall out of the magazine 5. This reduces both cost and complexity, which in turn reduces the risk that a fault occurs. Thus, instead of sensors and complex control systems, the magazine mover 15 may thus be rotated until it hits upon a rod in the magazine which will prevent further rotation.

As is illustrated in figure 4a the rod gripping arrangement 31 may comprise a first section 311 and a second section 313. When the magazine mover 15 is in the rod gripping position the second section 313 of the rod gripping arrangement 31 may block or lock a rod into the magazine 5. According to some embodiments the rod gripping arrangement 31 may be arranged such that when the first section 311 is in contact with a rod placed in the magazine 5 the second section 313 of the rod gripping arrangement 31 will confine a rod into the current groove 7 in the magazine 5 in which the rod is resting and thereby secure the rod in its position in the magazine 5. By confining is herein meant that the second section 313 will prevent rods from moving out of or being placed into the current groove 7 in the magazine 5.

The magazine mover 15 may be arranged such that the magazine 5 may only be locked to the magazine mover 15 when they are arranged in specific positions relative to each other. These positions may be chosen such that the magazine mover 15 is in a rod gripping position when the magazine mover 15 and the magazine 5 are locked to each other. This can be achieved by providing the magazine mover 15 with holes or openings 23 arranged for connecting the magazine mover 15 and the magazine 5. The openings 23 may, seen in a direction parallel to the rotation axis of the magazine mover, be arranged in a circle or arc of a circle at a constant distance from the rotation axis of the magazine mover 15. The locking element 171 of the force means 17 may, as has been previously described, be arranged to engage with one of the openings 23 which are arranged in the magazine mover such that the force means 17 and thereby the magazine 5 are connected to the magazine mover 15. The placement of the openings 23 on the magazine mover 15 will then define fixed locking-positions between the magazine mover 15 and the magazine 5, since the magazine mover 15 must be rotated to the right position on the common shaft 19 relative to the magazine 5 in order for the locking element 171 to be able to engage with a specific opening 23. The openings 23 may be arranged at a distance from each other which coincides with the distances between the grooves 7 in the magazine 5. A specific opening 23 will thereby correspond to a specific groove 7, i.e. when the locking element 171 engages a specific opening 23 the rod gripping arrangement 31 will act as a catch for a certain rod in the magazine 5 and thereby secure the rod in the groove 7 in which it rests. Other ways of locking the magazine 5 to the magazine mover 15 is also certainly possible.

Through this embodiment it is achieve that the magazine 5 and the magazine mover 15 are always positioned according to predetermined positions relative to each other during rotation of the magazine 5, as well as that the rods during rotation are always secured by the magazine mover 15.

The rod feeding device 1 further comprises at least one moveable picking arm 13 arranged to being able to be moved to a first position where the picking arm 13 may place or remove rods from the magazine 5 via the access position 1 1. The picking arm 13 is e.g. illustrated in figure 1 , 2 and 6. The rod feeding device 1 may comprise one or a plurality of picking arms 13. In a preferred embodiment the rod feeding device 1 comprises two picking arms 13. Hereinafter only one picking arm 13 will be described, with the understanding that several picking arms may be arranged in the same way.

The picking arm 13 may be arranged to move rods to and from the magazine 5. The picking arm 13 may e.g. be moved between the positions by a linear displacement of the arm 13 or by rotation. According to a preferred embodiment the picking arm 13 is displaced by rotation. The picking arm 13 may for this purpose be fixedly arranged to a shaft 25 which is rotatable arranged to the frame 3, e.g. through rotation bearings. A third force means 27, which is e.g. illustrated in figure 1 , may be arranged to achieve a rotation of the shaft 25 and thereby the picking arm 13. By arranging the shaft 25 at a suitable position relative to the magazine 5, the picking arm 13 may be rotated from a free position 12 outside of the frame 3 and the magazine 5 where rods may be picked up or offloaded for usage at e.g. a drilling hole, and the access position 1 1 where rods may be placed in or removed from the magazine 5. In figures 1 and 2 the picking arm 13 is in the access position 1 1. In figure 6 the picking arm 13 is shown both in the access position 1 1 (to the left in figure 6) and the free position 12 (to the right in figure 6).

The third force means 27 is according to one embodiment arranged such that it can rotate the picking arm 13 between two end positions, an outer end position outside of the magazine 5 and an inner end position at the access position 1 1. This may e.g. be achieved by the picking arm 13 being in the end position at full deflection of the third force means 27. In this way a device is achieved which has mechanical stops at the working positions, i.e. at the access position 11 and the free position 12 outside of the magazine where the picking arm 13 collects or leaves rods. The advantage with this is that there is no need for gauges or sensors to make sure that the picking arm 13 is correctly placed in relation to the magazine 5 at operation.

The third force means 27 may e.g. be a double acting hydraulic cylinder, the piston rod of which is fastened to a fastening means 29 arranged to the shaft 25. A rotating movement of the shaft 25 and thereby the picking arm 13 may then in a known manner be achieved by a linear movement of the piston in one direction or the other of the hydraulic cylinder. One end position in the hydraulic cylinder may according to one embodiment correspond to the picking arm 13 being positioned in the access position 11 and the other end position in the hydraulic cylinder may correspond to the picking arm 13 being positioned in the free position 12 outside the magazine 5 and the frame 3.

When the magazine mover 15 is placed between the magazine elements 5a, 5b, as described above, the picking arm 13 may be places such that it when it is displaced to the access position 11 is positioned between the magazine mover 15 and a magazine element 5a, 5b. The rod feeding device 1 comprises two picking arms 13 according to a preferred embodiment. The magazine mover 15 may then, as is illustrated in figure 1 and 2, be positioned between the picking arms 13 when they are displaced to the access position 11. The picking arms 13 may in turn, when they are displaced to the access position, be positioned between the magazine elements 5a, 5b. Thereby a compact arrangement of the rod feeding device 1 , as well as a stable locking of the rods to the picking arms 13 when placing rods into or removing rods from the magazine 5 is achieved.

Even though the above described placement of the magazine mover 15 and the picking arms 13 is preferred, the magazine mover 15 and the picking arms 13 may be placed at other positions, e.g. outside of the magazine elements 5a, 5b. Furthermore, more than one magazine mover 15 may be used, e.g. one outside each of the magazine elements 5a, 5b.

According to some embodiments the picking arm 13 may comprise a gripping device 51 arranged to be able to grip a rod.

By arranging the picking arm 13 with a gripping device 51 arranged to be able to grip a rod, safe handling of the rods when they are being moved by the picking arm 13 is achieved. The picking arm 13 may, as is illustrated in figure 6, be elongated and arranged with a gripping end 53, intended to grip a rod, and an opposing end, a fastening end 55, fixedly arranged to a displacement device, e.g. a rotatable shaft 25. The gripping end 53 may be arranged with a flat or inclined gripping surface 57 comprising a rod seat 59 in which a rod is intended to rest when being moved. The rod seat 59 may be arranged with a rounded surface which extends from the gripping surface 57 and around at least a part of the periphery of the rod when it is resting in the seat 59. The rod seat 59 may be arranged on one of the sides of the gripping end 53 such that a cup-shape or hook-form is formed by the rod seat 59 and the gripping surface 57.

A locking device 61 may be arranged to be able to lock the rod in the rod seat 59. It may for example be arranged to be moved up from and down into the gripping surface 57. The locking device 61 may be arranged at a distance from the rod seat which is somewhat smaller than the diameter of the rod. It is thereby achieved that when the locking device 61 is moved out of the gripping surface a rod resting in the rod seat is wedged to the seat. The locking device 61 may alternatively be arranged at a distance from the rod seat 59 which is equal to or somewhat bigger than the diameter of the rod. The picking arm 13 may thereby allow for a small play of the rod when gripping which may facilitate the gripping action. The locking device 61 may be arranged with a bowl- shaped surface. Thereby a better locking of the rod is achieved. The radius of curvature of the bowl-shaped surface may substantially correspond to the radius of the rod, or if the cross section of the rod is not round an approximate radius of the rod. In this way a better locking of the rod is achieved. The locking device 61 may in this way be brought between an active state when it is sticking out of the gripping surface 57 and may lock the rod in the rod seat 59 and a passive state when it is brought down into the gripping surface 57. The locking device 61 may be arranged such that it in the passive state presents a flat surface together with the gripping surface 57. The locking device may for example be moved between the two positions through the usage of hydraulic or electric control.

The picking arm 13 may according to one embodiment be positioned in the access position 11 such that the rod seat 59 is located radially closer the rotational axis of the magazine 5 than the in the radial direction innermost surface of a rod or the plurality of rods which are resting in the magazine 5. With radially is herein meant the radial direction from the rotational axis of the magazine 5. By the gripping arm 13 having been moved to the access position 11 such that the rod seat 59 is located closer to the rotational axis of the magazine 5 than the innermost surface of the rods in the magazine 5, the magazine 5 may rotate a rod to the picking arm 13 without hitting the rod seat 59. The rod will instead first contact the gripping surface 57. The gripping rod 13 may thereafter be moved such that the rod is placed in the rod seat 59, where after the locking device 61 may be locked in the rod seat. The picking arm 13 is shown moved to the access position 11 in the left part of figure 6. Thus, when the magazine 5 is rotated in the direction R _m a rod in the magazine 5 will be placed on the gripping surface 57 of the picking arm 13. Since the picking arm 13 is positioned in the access position 11 in such a way that the rod seat 59 is located closer to the rotational axis of the magazine 5 (which coincide with the rotational axis of the shaft 19) than the rods in the magazine 5, the rods will not hit the rod seat 59 during rotation to the picking arm 13 and the gripping surface 57. The picking arm 13 may thereafter rotate in the direction R _p , such that the rod which due to the rod gripping arrangement 31 is secured in its groove 7 in the magazine 5, is placed in the rod seat 59. The rod may thereafter be locked to the rod seat 59 using the locking device 61. The picking arm 13 may thereafter rotate further in the direction R _p to a free position 12 outside of the magazine 5 and drop the rod. The rod may alternatively be secured in the rod seat 59 during the rotation of the picking arm 13 from the access position 11 to the free position 12. The picking arm 13 may in this way not need to stop during the rotation, for example if the third force means 27 operate using only two end positions. To the right in the figure the picking arm 13 is illustrated positioned in a free position 12 outside of the magazine having a rod secured in the rod seat 59 by the locking device 61.

Through what has been described above there is achieved a rod feeding device which ensures that the rods are secured during the entire movement out of or into the magazine 5. This is ensured by the magazine mover 15, through the rod gripping arrangement 31 , locking the rods in the magazine 5 during rotation, as well as by the picking arm 13 securing the rods during movement to and from the access position 11. By the magazine mover 15 being disconnected from the magazine 5 and rotating relatively to the magazine 5 when they are not connected the magazine mover 15 is able to both secure rods and also rotate away from the magazine 5 so that the picking arm 13 may fetch or place rods in the magazine 5. Furthermore, since the magazine mover 15 and the magazine 5 can be locked to each other it is possible for the magazine mover 15 to rotate the magazine 5. Thus, no extra components is needed which rotates the magazine 5 separately. The rod feeding device 1 will thus be less complex by requiring fewer components which reduces the risk that a component will break.

A method for picking rods out of the rod feeding device 1 and a method of placing rods in the rod feeding device 1 will now be described with reference to figure 7 and 8. Method steps which are optional are represented by dashed lines in the figures.

The method steps which are described below may e.g. be performed by a control unit.

Figure 7 show an exemplifying method for removing rods from the rod feeding device 1. The method comprises: to rotate 702 the magazine 5 in a first direction such that a groove 7 in the magazine 5 containing a first rod is positioned in the access position 1 1 , wherein the rotation of the magazine 5 is performed by the magazine mover 15 in such a way that the first rod during the displacement is secured in its position in the magazine 5. The method further comprises to remove 703 the first rod from the magazine 5, wherein the removal is performed with the picking arm 13 in such a way that the first rod is secured by the picking arm 13 during the removing method.

By following the above described method a removing of a rod from the magazine wherein the rod is secured during the entire method is achieved. Thus, there is no risk that the rod will fall out of the magazine 5 or from the picking arm 13 during the removing method. Thereby the number of operational stops are minimized.

The method may further comprise: to lock 701 the magazine 5 to the magazine mover 15 when the magazine mover 15 is placed in the rod gripping position, wherein the rod gripping arrangement 31 secures the first rod in its position in the magazine 5, to rotate 702 the magazine mover 15 and thereby the magazine 5 in the first direction so that the rod gripping arrangement 31 and thereby also the groove 7 in the magazine 5 containing the first rod is positioned in the access position 1 1.

The step of locking 701 the magazine 5 to the magazine mover 15 is thus performed before the rotation occurs. The rod is thus secured by the rod gripping arrangement 31 securing the rod in the groove 7 in the magazine 5 in which it is resting. This is ensured by locking the magazine 5 to the magazine mover 15 when the magazine mover 15 is positioned in the rod gripping position. The magazine mover 15 may thus in a first step rotate to the rod gripping position. Through the shape of the magazine mover 15 and the rod gripping arrangement 31 the rod will then be secured in its groove 7 in the magazine 5. By thereafter rotating 702 the magazine mover 15 and the magazine 5 so that the rod gripping arrangement 31 is positioned in the access position 11 , the groove 7 with the rod will also be positioned in that position. The rod is at the same time secured during the entire rotation by the rod gripping arrangement 31. When the rod gripping arrangement 31 and the groove 7 are positioned in the access position 11 the picking arm 13 may thereafter pick the rod out of the magazine 5 at the access position 11.

The method may even more specifically comprise to move the picking arm 13 to the access position 11 so that it is ready to pick a rod out of the magazine 5, as well as to lock the magazine 5 to the frame 3. The magazine mover 15 is thereby free to rotate relatively to the magazine 5. The method may further comprise to rotate the magazine mover 15 in a first direction to the rod gripping position. The rod gripping arrangement 31 will secure the first rod in its groove 7 in the magazine 5 since the magazine mover is in the rod gripping position. The method may further comprise to lock the magazine 5 to the magazine mover 15. The magazine 5 will thereby rotate when the magazine mover 15 rotates. The method may further comprise to rotate the magazine mover 15 and thereby the magazine 5 in a second direction opposite to the first direction so that the rod gripping arrangement 31 is positioned in the access position 11 , as well as to activate a gripping device 51 of the picking arm 13 in order to grip the rod. The method may further comprise to lock the magazine 5 to the frame 3. The magazine mover 15 may now once again rotate free from the magazine 5. The method may further comprise to rotate the magazine mover 15 in the second direction to an open position where the gripping arrangement 31 of the magazine mover 15 does not secure the first rod in its groove in the magazine 5, as well as to move the picking arm 13 with the first rod from the magazine 5.

The activation of the gripping device 51 of the picking arm 13 may comprise the steps of moving the gripping arm 13 such that the rod is placed in a rod seat 59 of the picking arm and/or the step of with a locking device 61 lock the rod in the rod seat 59, for example by moving the locking device 61 out of the gripping surface 57. Since the rod is secured in its groove 7 in the magazine 5 because of the magazine mover 15 and the gripping arrangement 31 , a movement of the picking arm 13 will lead to a relative movement between the rod and the picking arm 13 so that the rod is placed in the rod seat 59. This is advantageous if the picking arm 13 is arranged with a rod seat 59 which is arranged to encompass a part of the periphery of the rod. When the picking arm 13 is moved to the access position 11 it must then be placed such that the rod seat 59 is not in the way of the rod when the magazine mover 15 rotates the rod to the access position 11. If the picking arm 13 is moved through rotation the picking arm 13 may thus be rotated in a first direction relative to its rotational axis to the access position 11 so that the rod seat 59 does not block the magazine 5 with rods from rotating to the picking arm 13. The picking arm 13 may thereafter, as part of the activation of the gripping device 51 , be rotated in a second direction opposite to the first direction in order to achieve that the rod is positioned in the rod seat 59. The rod locking device 61 may thereafter secure the rod in the rod seat 59. The picking arm 13 is during the entire gripping action in the access position 11.

The rod feeding device 1 is also capable of performing certain steps at the same time as other steps are performed. The magazine mover 15 may for example rotate up to the magazine 5 and be locked to it while the picking arm 13 is dropping of a rod outside the rod feeding device 1. The magazine mover 15 is thereby ready to rotate the magazine 5 with the rod as soon as the picking arm 13 is in the access position 11.

By following the above described method it is thus achieved that a rod is removed from the magazine 5. The rod may thereafter by used for e.g. rock drilling. The method may thereafter be repeated in order to remove additional rods from the magazine 5. Furthermore, since the magazine mover 15 moves between indexed positions having mechanical stops which ensure that the different components are positioned correctly before the next step of the method is performed, no sensors are needed in order to determine whether the picking arm 13, the magazine mover 15 or the magazine 5 are positioned correctly with regards to each other.

Figure 8 shows an exemplifying method for placing rods in the rod feeding device 1. The method comprises: to with the picking arm 13 collect 801 a first rod outside the magazine 5, as well as to place 802 the first rod in a groove 7 in the magazine 5 which is positioned in the access position 11. The method further comprises to rotate 804 the magazine 5 in a second direction until the first rod is secured by the securing

arrangement 9, wherein the rotation 804 is performed by the magazine mover 15 in such a way that the first rod is secured in its position in the magazine 5 during the

displacement.

By following the steps outlined above a rod may be placed in the magazine 5 in a secure way. Since the rod is secured during the entire method the risk of the rod falling out of or being incorrectly angled in relation to the magazine 5, magazine mover 15 or picking arm 13 which may lead to stops in the operation is minimized.

The rotation of the magazine 5 may further comprise: to lock 803 the magazine 5 to the magazine mover 15 when the magazine mover 15 is positioned in the rod gripping position, wherein the rod gripping arrangement 31 secures the first rod in its position in the magazine 5. The method may further comprise to rotate 804 the magazine mover 15 and thereby the magazine 5 in the second direction until the first rod is secured by the securing arrangement 9.

The rod is thus secured in the magazine 5 by the rod gripping arrangement 31 locking the rod in the groove 7 in the magazine 5 in which the rod is resting. This is ensured by locking 803 the magazine 5 to the magazine mover 15 when the magazine mover 15 is positioned in the rod gripping position before the rotation is performed. The magazine mover 15 may thus in a first step be rotated to a rod gripping position. The shape of the magazine mover 15 and the rod gripping arrangement 31 will then ensure that the rod is secured in its groove 7 in the magazine 5. By thereafter rotating the magazine mover 15 and the magazine 5 until the rod is secured by the securing arrangement 9 it is ensured that the rod is secured by the rod gripping arrangement 31 during the entire rotation. When the rod thereafter is secured by the securing

arrangement 9 the magazine mover 15 may be disconnected from the magazine 5 and rotated away from the current position relative to the magazine 5 in order to prepare the collection of a new rod.

The method for placing rods in the rod feeding device 1 may even more specifically comprise to move the picking arm 13 to a rod outside of the magazine 5 and activate a gripping device 51 of the picking arm 13 in order to grip the rod. The method may further comprise the steps of moving the picking arm 13 with the rod to the access position 1 1 so that the rod is placed in a groove 7 in the magazine 5 as well as to lock the magazine to the frame 3. The magazine mover 15 may now rotate relative to the magazine 5. The method may further comprise to rotate the magazine mover 15 in a first direction to the access position 1 1 as well as deactivating the gripping device 51 of the picking arm 13 in order to drop the rod. When the magazine mover 15 is in the access position 1 1 it will also be in the rod gripping position since the rod which is to be secured is positioned in a groove 7 positioned in the access position 1 1. Since the rod is locked in its position in the magazine 5 when the magazine mover 15 is in the rod gripping position, the picking arm 13 may let go of the rod. The method further comprises to move the picking arm 13 away from the rod as well as locking the magazine 5 to the magazine mover 15. The magazine mover 15 may now rotate the magazine 5, since they are connected. The method thus further comprises to rotate the magazine mover 15 and thereby the magazine 5 in the first direction until the rod is secured by the securing arrangement 9, to lock the magazine 5 to the frame 3 as well as to rotate the magazine mover 15 in a second direction opposite to the first direction to an open position where the rod gripping arrangement 31 of the magazine mover 15 does not lock a rod in its groove in the magazine 5.

The activation of the gripping device 51 of the picking arm 13 may comprise the step or the steps which have been described above in conjunction with the method of removing rods from the magazine.

The deactivation of the gripping device 51 of the picking arm 13 may comprise the step of with the locking device 61 releasing the rod from a rod seat 59 of the picking arm 13, for example by the gripping device 51 moving the locking device 61 down into the gripping surface 57. The deactivation may also comprise the step of moving the picking arm 13 such that the rod is freed from the rod seat 59. With freed is herein meant that the rod no longer rests in the rod seat 59.

In order to be able to place the rod in the magazine 5 the magazine 5 must be positioned such that a rod is placed in a free groove 7 when the picking arm 13 is moved to the access position 1 1. This will usually be the case because of the sequential operation of the rod feeding device 1. If required, the magazine mover 15 may of course in a preliminary step rotate the magazine 5 down to the correct position and thereafter rotate further by itself in order to open the magazine 5 for the picking arm 13. To move the picking arm 13 to a rod outside of the magazine 5 may for example entail moving the picking arm 13 to a position where a set of rods are placed for reloading of rods to the magazine 5.

By following the above described method it will be achieved that a rod is placed in the magazine 5. The method may thereafter be repeated in order to place additional rods in the magazine 5. In the same way as for the removal of rods, the method of placing rods in the magazine 5 does not require any sensors or gauges in order to determine whether the picking arm 13, the magazine mover 15 or the magazine 5 are positioned correctly with regards to each other. This is the case since the magazine mover 15 and the picking arm 13 are moving between mechanical stops which ensures that the different components are placed correctly before the next step in the method is performed.

The rod feeding device and the method which have been described herein are not limited to the field of rock drilling, instead all manner of work where several rods need to be used are possible applications.