WO2001086108A1

WO2001086108A1 - Rock drilling machine and alignment piece

Info

Publication number: WO2001086108A1
Application number: PCT/FI2001/000453
Authority: WO
Inventors: Jarmo Heinonen; Jorma MÄKI; Timo Muuttonen
Original assignee: Sandvik Tamrock Oy
Priority date: 2000-05-11
Filing date: 2001-05-10
Publication date: 2001-11-15
Also published as: FI20001123A; FI109229B; AU2001260354A1

Abstract

The invention relates to a rock drilling machine and an alignment piece. The drilling machine comprises an axial piston unit (19) provided with axial pistons (12) acting on a shank through bearing members (13) and a support sleeve (10). A joint surface between a first frame part (1) of the drilling machine and a second frame part to be attached thereto is provided with an alignment piece comprising a guide sleeve (23) and a guide ring (25), cylindrical spaces (28) surrounding the percussion piston being provided in the guide ring for the bearing members (13). The alignment piece further comprises locking surfaces to allow countertorque caused by the rotating of the shank to be transmitted between the attached frame parts, and locking surfaces for positioning the guide ring around the axis of the percussion piston such that each bearing member is coaxial with the axial piston it coincides with.

Description

ROCK DRILLING MACHINE AND ALIGNMENT PIECE

[0001] The invention relates to a rock drilling machine comprising at least two frame parts of which a first frame part is arranged to the front end of the drilling machine and a second frame part is attached to a joint surface provided at the rear end of the first frame part, the first frame part comprising a shank, where a tool is to be fastened, which drilling machine further comprises a pressure-fluid-operated percussion device and a rotating device, a percussion piston of the percussion device being arranged to reciprocate and to strike the shank, and the rotating device being arranged to rotate the shank by means of a rotating sleeve arranged around it, and in which drilling machine there is a support sleeve around the shank, which support sleeve comprises a support surface acting on the shank in the axial direction, the support sleeve being subjected to the impact of axial pistons arranged into cylindrical spaces formed around the front part of the percussion piston, the tail ends of the axial pistons being subjected to pressure fluid to move the pistons in the axial direction, and in which a guide ring is arranged between the axial pistons and the support sleeve, the guide ring being provided with cylindrical spaces arranged for bearing members and coinciding with the axial pistons, the guide ring further comprising alignment members to ensure that each bearing member arranged into a cylindrical space is coaxial with the axial piston it coincides with.

[0002] Further, the invention relates to an alignment piece to be arranged between a first and a second frame part of a rock drilling machine. [0003] FI Patent 84,701 teaches a rock drilling machine in which the position of the shank is adjusted by means of axial pistons and a support sleeve arranged behind the shank. The pressure acting on all the axial pistons pushes the shank to an optimum percussion point, or, when a lower percussion force is desired, beyond that point. In addition, the pistons allow the shank to move backwards by the impact of a strong return pulse, the pistons thereby receiving the stress created.

[0004] Further, FI Patent 98,402 discloses axial pistons of an axial bearing that act on a shank through bearing members. These bearing members are arranged into cylindrical spaces formed into a guide ring placed in front of the pistons. A problem encountered here is how to align the guide ring such that the bearing members always set to be precisely coaxial with the axial pistons. To allow the position of the guide ring to be correctly determined around the axis of the percussion piston, radial projections are arranged on the outer circumference of the guide ring and corresponding recesses in the frame of the drilling machine. For sufficient precision to be achieved, the guide ring and the frame recesses must be extremely carefully dimensioned with respect to one another. It is usually necessary to use a clamp fit between the guide ring and the recesses, the mounting of the guide ring being therefore difficult and slow.

[0005] Another problem has risen from how to transmit countertorque caused by the rotating of the shank between the frame parts to be joined. Countertorque tends to rotate the frame part comprising the shank around the axis of the shank. Due to lack of space, suitable mating surfaces are usually difficult to form on the joint surface between the frame parts because, to ensure good operability, the cross-section of the front frame of the drilling machine is preferably made as small as possible.

[0006] It is an object of the present invention to provide a novel and improved arrangement allowing axial pistons and bearing members belonging to an axial bearing to be positioned with respect to one another and countertorque caused by the rotating of the shank to be transmitted between the frame parts to be joined.

[0007] The rock drilling machine of the invention is characterized in that the rock drilling machine is provided with an alignment piece between the first and the second frame part, the alignment piece comprising a guide sleeve and a guide ring arranged around a percussion piston; that the guide sleeve comprises guide surfaces for aligning the guide ring to be coaxial with the percussion piston; that the alignment piece is provided with a first locking surface which is arranged against a mating surface formed on the joint surface of the second frame part to determine the position of the guide ring around the axis of the percussion piston to allow the bearing members and the axial pistons to be aligned; and that the alignment piece comprises a second locking surface arranged against mating surfaces formed on the joint surface of the first frame part such that the countertorque caused by the rotating of the shank is arranged to be transmitted through the first and the second locking surface from the first frame part to the second frame part. [0008] Further, the alignment piece of the invention is characterized in that the alignment piece comprises a guide sleeve provided with a coaxial outer sleeve and guide ring; that the guide ring comprises an opening for a percussion piston of the drilling machine and cylindrical spaces for bearing members of an axial bearing of the rock drilling machine, the spaces being parallel with the axis of the guide ring and arranged to surround said opening; that the alignment piece comprises a first locking surface to be arranged against a mating surface formed on the second frame part; and that the alignment piece comprises a second locking surface to be arranged against a mating surface formed on the first frame part.

[0009] A basic idea of the invention is that the alignment piece comprises a guide sleeve arranged around the percussion piston. The guide sleeve in turn comprises a coaxial outer sleeve and guide ring. Further, the guide ring comprises cylindrical spaces provided for bearing members and arranged parallel with the percussion piston. On the outer sleeve, guide surfaces are formed to guide the guide sleeve to be coaxial with the axial piston unit. Further, the alignment piece comprises at least one locking surface to allow the turning of the alignment piece around the axis of the percussion piston to be determined such that the bearing members arranged into the cylindrical spaces of the guide ring are precisely coaxial with their respective axial pistons. The alignment piece is arranged between the frame parts to be joined, the alignment piece therefore comprising locking surfaces and the frame parts to be joined comprising mating surfaces corresponding to the locking surfaces such that countertorque caused by the rotating of the shank is transmitted from the first frame part to the second frame part and further to feed equipment. In addition, an alignment piece allows the frame parts to be joined to set into a predetermined position with respect to one another, whereby the structure is not subjected to any extra load caused by an incorrect position. Furthermore, the locking surfaces receive the torque acting on the alignment piece through the bearing members. This kind of alignment piece is compact in structure and rapid to install. A basic idea of a first preferred embodiment of the invention is that the alignment piece comprises a locking sleeve parallel with and adjacent to the guide sleeve, the rotating shaft being preferably arranged through the locking sleeve. The locking sleeve therefore comprises locking surfaces guiding the alignment piece around the axis of the percussion piston such that the cylindrical spaces in the guide ring and the bearing members arranged therein are turned to be precisely coaxial with the axial pistons. Further, the locking sleeve comprises locking surfaces which allow countertorque caused by the rotating of the shank to be transmitted from the frame part comprising the shank to the next frame part. Since the locking surfaces of the locking sleeve are at a distance from the axis of the percussion piston, they are better able to receive torque. For the same reason, looser fittings can be used and yet a more precise alignment than before can be achieved. The structure of the alignment piece allows it to be arranged in place only in one position, thus eliminating the risk of faulty installation.

[0010] A basic idea of a second preferred embodiment of the invention is that the alignment piece is a sleeve-like piece and its outer circumference is provided with plane-like surfaces parallel with the longitudinal axis of the alignment piece, the surfaces serving as locking surfaces.

[0011] A basic idea of a third preferred embodiment of the invention is that the frame of the drilling machine comprises three frame parts. The first frame part comprises a shank and the third frame part a percussion device. The second frame part is a mounting frame serving as a mounting base between the other frame parts. The mounting frame is mounted on bearings to be movable with respect to a feed beam of the drilling machine and it transmits the forces acting on the drilling machine to the feed equipment. The mounting frame comprises two bars parallel with the feed beam and arranged at a distance from one another, a transverse axial support being arranged between the bars. The front and rear surfaces of the axial support comprise joint surfaces to which the other frame parts are attached. In this embodiment the axial piston unit is arranged in connection with the axial support. The alignment piece is arranged between the mounting frame and the first frame part, whereby the locking surfaces of the alignment piece transmit countertorque caused by the rotating of the shank from the first frame part to the mounting frame and further to the feed equipment.

[0012] The invention will be described in greater detail with reference to the accompanying drawings, in which Figure 1 is a schematic perspective view of a rock drilling machine of the invention;

Figure 2 is a schematic sectional side view of part of the rock drilling machine structure shown in Figure 1 ;

Figure 3a is a schematic view showing a mounting frame belonging to the rock drilling machine of the previous Figures seen from the shank side, Figure 3b showing the same from the percussion device side; Figure 4a is a schematic view showing an alignment piece of the invention in perspective, Figure 4b showing it from direction A, and Figure 4c showing a side view of the structure in a cross-section along line E - E;

Figure 5 is a schematic view of a frontal surface of a first frame part of the drilling machine, seen from the direction of the mounting frame;

Figure 6 is a schematic sectional side view of part of the drilling machine of the invention; and

Figure 7a shows an alignment piece of the invention seen from the rear end of the piece, Figure 7b showing it from its front end, and Figure 7c showing a cross-sectional side view of the piece.

[0013] The rock drilling machine of Figure 1 comprises three frame parts which are to be joined together, although here, for the sake of clarity, they are shown detached. Starting from the front end of the apparatus, it comprises a first frame part 1 , a second frame part, i.e. a mounting frame 2 in this case, and a third frame part 3. The first frame part comprises a shank and a gearbox for transmitting rotating force delivered from a rotating device to the shank. The third frame part comprises a percussion device and a rotating device. The mounting frame, in turn, serves as a mounting base between the frame parts and transmits the forces caused by the drilling and the feeding of drilling machine to feed equipment 40 of the apparatus. Consequently, the first and the second frame part may be easily changeable modules to be attached to the mounting frame. The drilling machine is mounted on bearings with respect to a feed beam using slide blocks 4 arranged to the mounting frame, whereby a separate carriage is not needed between the drilling machine and the feed beam.

[0014] Figure 2 is a schematic view of part of the drilling machine structure. The drilling machine comprises a percussion piston 5 and a shank 6 coaxial with the piston. The percussion piston reciprocates by impact of pressure fluid and strikes the shank. The shank transmits the impact energy to a tool fastened to the shank and further to the rock to be drilled. Moreover, the shank is rotated by means of a rotating sleeve 7 arranged to the gearbox of the first frame part 1. The rotating sleeve around the shank is driven by a rotating shaft 8 which in turn is rotated by a rotating device 9 arranged to the third frame part 3. The shank is arranged such that it can move in the axial direction. Further, there is a support sleeve 10 arranged around the rear end of the shank, the front end of the sleeve being provided with a support surface 11 that is in contact with a corresponding support surface on the shank. The support sleeve thus supports the shank and, by impact of friction acting between the support surfaces, it is able to rotate simultaneously with the shank. The support sleeve is supported by an axial piston unit such that a plural number of axial pistons 12 are arranged behind the support sleeve to surround the front end of the percussion piston 5, the axial pistons exerting a mechanical impact through bearing members 13 on the rear surface of the support sleeve. Each of the axial pistons is arranged into a separate cylindrical space provided in connection with the axial support 14 and parallel with the percussion piston. The bearing members, in turn, are arranged into a guide ring 15 provided between the axial pistons and the support sleeve, the guide ring comprising cylindrical spaces provided for the bearing members and coaxial with the axial pistons. Between the front end of the bearing members and the rear end of the rotating support sleeve is thereby formed an axial bearing surface which is why the bearing members are made of hard metal, or some other extremely wear-resistant material. There are pressure fluid conduits 16 leading to the rear end of the axial pistons, which allows the position of the shank to be changed in the axial direction by regulating the pressure. This allows to adjust the percussion force of the drilling machine or the contact of the drill bit with the rock. By impact of the pressure supplied behind the axial pistons, the pistons exceed the feed force of the feed equipment and push the shank to an optimal percussion point with regard to the operation of the percussion device. Alternatively, if lower percussion force is to be used, for example due to weak rock material, the pistons can be used for pushing the shank beyond the optimal percussion point. Further, the pressure behind the axial pistons can be maintained at a specific level to keep the shank in a specific position.

[0015] Figure 3a shows the mounting frame seen from the direction of the shank. The mounting frame comprises two bars 18a and 18b parallel with the feed beam, the bars being provided with slide blocks fastened thereto, the slide blocks serving as bearings between the mounting frame and the feed equipment. The bars are at a distance from one another, a substantially perpendicular transverse axial support 14 being arranged between them. Figure 3a shows a first joint surface 14a of the axial support against which the first frame part comprising the shank will be arranged, and Figure 3b shows a joint surface 14b against which the third frame part comprising the rotating device and the percussion device will be arranged. The axial support comprises the necessary openings for the fastening bolts of the frame parts and also openings for guiding the rotating shaft and the percussion piston through the support. The axial support opening formed for the percussion piston is provided with a sleeve-like axial piston unit 19 with an opening 20 in the middle for the percussion piston, cylindrical spaces 21 parallel with the percussion piston axis being provided around the opening. From the point of view of manufacturing and servicing, the axial piston unit is preferably a separate piece arranged into the opening made in the axial support and locked into a precise predetermined position with respect to the percussion piston axis by means of a locking screw, for example. When necessary, the axial piston unit may also be an integral part of the axial support. As shown in Figure 3b, the axial piston unit may further comprise a ring-like guide surface 22 extending to the second joint surface 14b of the mounting frame to facilitate the mounting of the third frame part.

[0016] Figure 4a shows a perspective view of a possible alignment piece construction. The alignment piece comprises a guide sleeve 23 provided with an outer sleeve 24 and a guide ring 15 at its front part, i.e. two sleeves one inside the other. The guide sleeve thus forms a kind of a nest which is placed on the projecting axial piston unit 19 before the frame parts are joined. Since the contact surface between the inner surface 26 of the outer sleeve and the axial piston unit is fairly large, the guide sleeve is guided to be precisely coaxial with the axial piston unit. In the middle of the guide ring, there is provided an opening 27 for the percussion piston, and, around the opening, there are cylindrical spaces 28 for the bearing members. The diameters of the cylindrical spaces are smaller than those of the axial pistons, the rear surface of the guide ring thus restricting the forward movement of the pistons. At the front end of the guide sleeve is further provided a guide surface 29 which sets into the recess made to the frontal surface of the first frame part. [0017] Adjacent to the guide sleeve 23 there is provided a parallel locking sleeve 30 having an opening 31 for the rotating shaft. The locking sleeve comprises a sleeve-like portion 32 and a lug 33 which attaches the locking sleeve to the outer circumference of the guide sleeve 23. On the rear side, the sleeve-like portion 32 of the locking sleeve extends further than the rear surface of the guide sleeve and thus serves as the first locking surface of the locking sleeve. This locking surface is arranged into the opening provided in the axial support of the mounting frame for the rotating shaft. This kind of construction takes up little space on the frontal surface of the frame part where it is to be attached to. Further, the transverse sides of the lug on the locking sleeve are provided with second locking surfaces 34 that set against the mating surfaces of the recess formed on the first frame part, as will be described in greater detail in connection with Figure 5.

[0018] As shown in Figure 4b, a recess 35 can be formed around some of the cylindrical spaces in the guide ring to allow axial pistons arranged at said openings to move a longer distance towards the shank than the other axial pistons. According to this principle, the axial bearing may be provided with a plural number of piston groups of different travel distances. This allows for an increasingly versatile adjustment for the percussion force of the drilling machine and the damping of the return pulse.

[0019] Figures 4a and 4c show parallel axes of the guide sleeve and the locking sleeve which are at a distance from one another. This creates torque arm between the guide sleeve and the locking sleeve, the locking sleeve being thereby able to receive well the countertorque caused by the rotating of the shank. In addition, since the first locking surface 32 of the locking sleeve that determines the correct turning position of the guide sleeve with respect to the axis of the percussion piston is at a longer distance from the axis of the percussion piston than in prior art arrangements, a sufficient alignment precision can be achieved with less precise manufacturing tolerances than before. Since a clamp fit is no longer needed to put the alignment piece in place, mounting is significantly easier and quicker. Nevertheless, the actual precision achieved in the positioning can be better than before.

[0020] Figure 4c shows that there is at least one conduit 36 between the guide sleeve and the locking sleeve for delivering lubricant from the space surrounding the rotating shaft to lubricate the bearing members. For the sake of clarity, Figures 2 and 4c also show line B - B indicating the joint surface between the first frame part and the second frame part.

[0021] When the rotating device is arranged into the same frame part with the shank, the rotating shaft naturally does not pass through the locking sleeve. Therefore the first locking surface of the locking sleeve is not necessarily sleeve-like, but it may also be a solid pin or the like. Further, the locking sleeve may only comprise a lug 33 extending across the joint surface between the frame parts. In that case the plane-like locking surfaces 34 on the sides of the lug set against the mating surfaces on the frame parts to be joined.

[0022] Figure 5 shows the frontal surface of the first frame part 1 , the surface being arranged against the front joint surface of the mounting frame after the alignment piece of Figures 4a-4c has first been arranged in place around the axial piston unit. The frontal surface of the first frame part comprises a recess 37, the guide sleeve thus being set entirely into an annular portion 37 of the recess and the lug of the locking sleeve into a recess portion 38 formed for it. The plane-like locking surfaces on the sides of the locking sleeve lug set against mating surfaces 39 formed to the recess, whereby the countertorque caused by the rotating of the shank is transmitted from the first frame part to the locking sleeve and, through the ring-like portion of the locking sleeve, further to the mounting frame. Consequently, the rotating of the shank does not cause any substantial countertorque on the third frame part.

[0023] Figure 6 shows yet another rock drilling machine of the invention comprising two frame parts. In this case the first frame part 1 comprises a shank 6, gearbox and rotating motor, and a second frame part 41 comprises a percussion device. Alternatively, the rotating device may be arranged into the second frame part. The second frame part is supported against feed equipment, either directly by means of slide blocks or using a carriage, the first frame part being in turn supported against the second frame part. Since the first frame part is not separately supported against the feed equipment, the first frame part may be an easily changeable module. This construction is also provided with an alignment piece arranged between the frame parts, around the percussion piston 5, to allow the countertorque caused by the rotating of the shank to be transmitted from the first frame part to the second frame part and further to the feed equipment. As shown in Figure 6, the rear end of the first frame part and the front end of the second frame part are provided with recesses for the alignment piece. At least the recess in the second frame part 41 is formed with dimension accuracy because the outer circumference of the recess aligns the alignment piece to be coaxial with the percussion piston axis. Further, the locking surfaces 42 at the rear end of the alignment piece determine the turning of the alignment piece around the percussion piston axis such that the cylindrical spaces in the guide ring 15 of the alignment piece and the bearing members 13 arranged therein are set to be precisely coaxial with the axial pistons 12 arranged at the front end of the second frame part 41. The front end of the second frame part is provided with drillings for the axial pistons.

[0024] Figures 7a-7c show the alignment piece used in the drilling machine of Figure 6. As shown in Figure 7a, the rear end of the alignment piece is provided with a guide ring 15 comprising cylindrical spaces 28 for the bearing members and, further, an opening 27 for the percussion piston. The outer circumference 43 of the alignment piece serves as a guide surface and sets precisely into the recess formed at the front end of the second frame part 41. The rear end of the alignment piece is provided with a first locking surface 42 and the recess on the joint surface of the second frame part with a corresponding mating surface, the planar surface and the mating surface thus determining the correct turning position of the alignment piece. To allow the otherwise rotationally symmetrical alignment piece to transmit the countertorque from the first frame part to the second frame part, also the front end of the alignment piece is provided with a locking surface 44 and the recess on the joint surface of the first frame part with a corresponding mating surface. The locking surfaces 42 and 44 are preferably planar surfaces formed on the outer circumference of the alignment piece and parallel with its longitudinal axis. The simple structure of the alignment piece and its suitability for manufacture can be considered as its advantages. In addition, the alignment piece occupies very little space on the frontal surfaces of the frame parts. It is to be noted that there may be a plural number of locking surfaces, and that they do not necessarily need to be planar; instead, it is sufficient that the turning position of the alignment piece can be accurately aligned with regard to the axial pistons and that the alignment piece and the frame part to be attached are prevented from rotating with respect to each other around the axis of the percussion piston. The alignment piece in question can be applied not only in the construction of Figure 6 but also for example in cases where the axial pistons are arranged into drillings made to the axial support of the mounting frame, or when the axial piston unit does not form a projection on the front part of the second frame part.

[0025] The drawings and the related specification are only meant to illustrate the idea of the invention. The details of the invention may vary within the scope of the claims.

Claims

1. A rock drilling machine comprising at least two frame parts of which a first frame part (1) is arranged to the front end of the drilling machine and a second frame part is attached to a joint surface provided at the rear end of the first frame part, the first frame part comprising a shank (6), where a tool is to be fastened, which drilling machine further comprises a pressure-fluid- operated percussion device and a rotating device (9), a percussion piston (5) of the percussion device being arranged to reciprocate and to strike the shank, and the rotating device being arranged to rotate the shank by means of a rotating sleeve (7) arranged around it, and in which drilling machine there is a support sleeve (10) around the shank, which support sleeve comprises a support surface (11) acting on the shank in the axial direction, the support sleeve being subjected to the impact of axial pistons (12) arranged into cylindrical spaces formed around the front part of the percussion piston, the tail ends of the axial pistons being subjected to pressure fluid to move the pistons in the axial direction, and in which a guide ring (15) is arranged between the axial pistons and the support sleeve, the guide ring being provided with cylindrical spaces (28) arranged for bearing members (13) and coinciding with the axial pistons, the guide ring further comprising alignment members to ensure that each bearing member arranged into a cylindrical space is coaxial with the axial piston it coincides with, c h a r a c t e r i z e d in that the rock drilling machine is provided with an alignment piece between the first and the second frame part, the alignment piece comprising a guide sleeve (23) and a guide ring (15) arranged around the percussion piston; that the guide sleeve comprises guide surfaces for aligning the guide ring to be coaxial with the percussion piston; that the alignment piece is provided with a first locking surface which is arranged against a mating surface formed on the joint surface of the second frame part to determine the position of the guide ring around the axis of the percussion piston to allow the bearing members and the axial pistons to be aligned; and that the alignment piece comprises a second locking surface which is arranged against mating surfaces formed on the joint surface of the first frame part such that the countertorque caused by the rotating of the shank is arranged to be transmitted through the first and the second locking surface from the first frame part to the second frame part.

2. A rock drilling machine according to claim 1, characterized in that the guide sleeve is provided with a parallel locking sleeve (30) attached thereto, the axis of the locking sleeve being at a distance from that of the guide sleeve; that the locking sleeve comprises a first locking surface arranged against the mating surface formed on the joint surface of the second frame part to determine the position of the guide ring around the percussion piston axis; and that the locking sleeve comprises a second locking surface arranged against the mating surfaces formed on the joint surface of the first frame part, the countertorque caused by the rotating of the shank being arranged to be transmitted through the first and the second locking surfaces from the first frame part to the second frame part.

3. A rock drilling machine according to claim 2, characterized in that the cylindrical spaces of the axial pistons (12) are formed into a sleeve-like portion which provides a projecting axial piston unit (19) at the front end of the second frame part; that the guide sleeve (23) is arranged around the axial piston unit, the guide sleeve guiding the guide ring to be coaxial with the axial piston unit; and that the rear end of the first frame part is provided with a recess (37) for the axial piston unit and the guide sleeve.

4. A rock drilling machine according to claim 3, characterized in that the axial piston unit (19) is a separate sleeve-like piece and that the axial piston unit is arranged in connection with an opening formed for the percussion piston in the attachment surface at the front end of the second frame part.

5. A rock drilling machine according to any one of claims 2 to 4, characterized in that the rotating device (9) is arranged into a different frame part than the shank (6); that the locking sleeve comprises an opening through which a rotating shaft (8) is arranged; and that first locking surface of the locking sleeve (30) is sleeve-like (32) and it is arranged into an opening made for the rotating shaft in the joint surface of the second frame part.

6. A rock drilling machine according to any one of claims 2 to 5, characterized in that the locking sleeve (30) is attached to the outer circumference of the guide sleeve (23) by means of a lug (33); that second locking surfaces (34) for the locking sleeve are formed on the transverse side surfaces of the lug; and that the joint surface at the rear end of the first frame part (1) is provided with a recess (38) for the lug and mating surfaces (39) for the locking surfaces (34) formed on the lug.

7. A rock drilling machine according to any one of the preceding claims, c h a r a c t e r i z e d in that the rock drilling machine comprises a mounting frame (2) provided with an axial support (14) which is transverse to feed equipment (40); that the first frame part of the rock drilling machine and the frame part comprising the percussion device are fastened to opposite sides of the axial support; that the mounting frame is mounted on bearings to the feed equipment of the rock drilling machine and arranged to transmit drilling and feed forces acting on the drilling machine to the feed equipment; that the axial pistons (12) are arranged in connection with the axial support of the mounting frame; and that the alignment piece is arranged between the first frame part and the mounting frame.

8. A rock drilling machine according to claim 1 , c h a r a c t e r i z e d in that the alignment piece is sleeve-like; and that the outer circumference of the alignment piece is provided with planar surfaces parallel with the longitudinal axis of the alignment piece to serve as locking surfaces (42, 44), the planar surfaces being arranged against the mating surfaces formed on the first frame part and, correspondingly, on the second frame part.

9. An alignment piece to be arranged between a first (1) and a second frame part of a rock drilling machine, c h a r a c t e r i z e d in that the alignment piece comprises a guide sleeve (23) provided with a coaxial outer sleeve (24) and guide ring (15); that the guide ring comprises an opening (27) for a percussion piston of the drilling machine and cylindrical spaces (28) for bearing members of an axial bearing of the rock drilling machine, the spaces being parallel with the axis of the guide ring and arranged to surround said opening; that the alignment piece comprises a first locking surface to be arranged against a mating surface formed on the second frame part; and that the alignment piece comprises a second locking surface to be arranged against a mating surface formed on the first frame part.

10. An alignment piece according to claim 9, c h a r a c t e r i z e d in that the guide sleeve is provided with a parallel locking sleeve (30) attached thereto, the axis of the locking sleeve being at a distance from that of the guide sleeve; that the locking sleeve comprises a first locking surface to be arranged against a mating surface formed on the frontal surface of the second frame part; and that the locking sleeve comprises a second locking surface to be arranged against a mating surface formed on the first frame part.

11. An alignment piece according to claim 10, characterized in that the locking sleeve comprises an opening for the rotating shaft of the rock drilling machine; and that the first locking surface of the locking sleeve is sleeve-like (32) which allows it to be arranged into the opening made for the rotating axis in the joint surface of the second frame part.

12. An alignment piece according to claim 10 or 11, characterized in that the locking sleeve is attached to the guide sleeve by a lug (33) and that a second locking surface (34) is formed on transverse side surfaces of the lug.