JP2017526840A - Bits, especially round shank bits - Google Patents

Abstract

The present invention relates to a bit (10, 11), in particular a round shank bit used in a cutting drum, a bit head (20) and a bit shank (40) for holding the bit in a bit holder (50). The bit head of the bit has at least one cutting area (20.3). A planar and / or concave ejection area (20.4) is arranged in the central area of the bit head, indirectly or directly connected to the cutting area (20.3). This bit has an optimized unloading function for waste debris material.

Description

  The present invention is a round shank bit used in a bit, particularly a cutting drum, comprising a bit head and a bit shank for holding the bit in a bit holder, the bit head of the bit being The bit having at least one cutting area.

  Such a bit is known on the basis of DE 3701905. This bit is composed of a bit head and a bit shank formed integrally with the bit head and formed as a round shank. The bit head and the bit shank are configured to be rotationally symmetrical about the central longitudinal axis. The transition from the bit head to the bit shank is formed as a collar, which is the maximum outer diameter of the bit head. The bit head tapers conically toward the bit tip. The bit tip is formed by a hard alloy insert. The bit is held in the corresponding receiving part of the bit holder in its bit shank by means of a clamping sleeve. The clamping sleeve engages in a groove surrounding the bit shank so that the bit is held in the axial direction but can rotate about its central longitudinal axis. This configuration has the advantage that the bit wears uniformly from all sides during its use.

  Such bits are used, for example, in so-called Surface Miner rotating cutting drums for crushing rocks and ground in large scale open pit mining. The waste material (Abraummaterial) is crushed by a bit fixed to the cutting drum, conveyed to the discharge part by the movement of the cutting drum, and then discharged from there by, for example, a charge belt system.

  The disadvantage of this described bit is that it has a low bit-carrying performance, especially for relatively soft waste material such as oil sands, based on the shaping of the bit.

  It is therefore an object of the present invention to improve the bit of the type described at the beginning and to provide a bit with improved transport function.

  The object of the invention is solved by the fact that the planar and / or concave ejecting area is arranged in the central area of the bit head, indirectly or directly connected to the cutting area. Depending on the cutting area, the ground or rock is dug up and crushed. The planar eject area captures waste debris material and transports it in the feed direction of the bit and the cutting drum. Due to the planar configuration of the ejection area, very finely crushed plastically deformable or sandy waste debris material is also reliably captured and transported in large quantities to the discharge section as the cutting drum rotates.

  In an embodiment where high cutting performance and a long service life of the bit are obtained, the cutting area is oriented in the feed direction (V) direction of the bit head at the end of the bit opposite the bit shank. At least one cutting element made of hard material, in particular of hard alloy, and / or the ejecting area, which is mounted on the front side of which is made of at least one plate-shaped hard material element, in particular of hard alloy And the hard material element is connected to the cutting element indirectly or directly. The cutting element and the plate-shaped hard material element protect the bit head region arranged on the rear side against abrasion due to polishing. At this time, particularly high wear resistance can be obtained if the hard material element is directly connected to the cutting element, and there is no gap between the two elements that may cause the waste debris substance to act.

  In an embodiment that can improve the discharge of particularly viscous or sandy waste debris material, the turning area is arranged indirectly or directly in the ejection area of the bit head, the turning area being , Extending toward the front side of the bit, and an excavator-shaped recess directed toward the front side of the bit is formed by the cutting region, the ejecting region, and the turning region. By this recess, for example, plastically deformable waste debris material is crushed in the cutting region and formed into a spherical shape or a roll shape via the eject region and the turning region. The waste debris material formed in this way is further conveyed by the eject area and held by the turning area. The sand-like waste debris material is retained in the recess by the turning region.

  In an embodiment that further reduces wear due to bithead polishing, the bithead has a retaining portion, the retaining portion is disposed in the cutting region and the ejecting region, the retaining portion being the cutting region and / or the ejecting region. 2 have side connection surfaces arranged on both sides of the holding portion, and the interval between the connection surfaces decreases from the front side toward the rear side of the bit. If comprised in this way, the width | variety of a holding | maintenance part will taper off toward the bit rear side from the bit front side exposed directly to waste debris material. Due to the undercut formed in this way, only a reduced mechanical load due to the waste material is applied to the connecting surfaces on the sides. As already mentioned, the front side subjected to a strong load can be protected by the cutting element and the hard material element, so that a long service life of the bit can be obtained. Another advantage is obtained by allowing the bit thus formed to be easily moved through the ground. This reduces the power used for the movement of the cutting drum and thus saves energy.

  According to a preferred variant of the invention, the cutting element is formed by a fixing member oriented towards the front side of the bit and an additional part oriented from the fixing member towards the rear side of the bit. The cutting element forms a cutting edge at the outermost end of the bit head, and the cutting element forms a lead-out surface from the cutting edge toward the fixing member and escapes toward the additional portion. A surface is formed. This ensures that the cutting edges that are subjected to mechanically strong loads and the areas that are directly connected to the cutting edges and that are also subjected to mechanically strong loads are protected against increased wear by the hard material. The This greatly increases the useful life of the bit head.

  In an embodiment in which the cutting element can be securely fixed to the holding part, the fixing member forms a contact surface, and the additional part forms a support part, and the cutting element uses a material-bonding type connecting part. , Between the contact surface and the contact area and / or between the support part and the support area of the holding part. The material-bonded joint can be formed, for example, by gluing or preferably by brazing. In order to form a particularly rigid joint, such a joint is also formed between the contact surface and the contact area and between the support part and the support area. Such a fixing on both sides can further reduce the risk of damage to the cutting element.

  In an embodiment that can extend the useful life of the bit head, the bit head is coated with an anti-wear coating layer, in particular by armor welding, in the cutting region, the ejecting region and / or the turning region. When configured in this manner, for example, in a cutting region that receives a special mechanical load, an anti-wear coating layer is provided on the connection surface of the side portion and the connection surface disposed on the extended portion of the flank surface of the cutting element. Can be provided, and thus these connecting surfaces can be protected against abrasion due to polishing. Correspondingly, the side connection surfaces in the ejection area of the bit head may also be protected by an anti-wear coating layer. Such a treatment can prevent the holding part on the rear side of the cutting element and the rear side of the hard material element from being eroded and thereby preventing the cutting element or the hard material element from being detached from the holding part. The turning region connected to the ejection region may be protected by being provided with an anti-wear coating layer toward the front side of the bit head. With such a treatment, the recesses in the bit head, which are directed towards the front side of the bit head and are directly exposed to the debris material, can be completely protected against premature wear due to polishing. Preferably, the cutting area that is subjected to the strongest load and the ejecting area that is also subjected to the strong load are protected by the cutting element and the hard material element toward the front side, and the turning area that is not heavily loaded is protected by the anti-wear coating Protected. This provides a relatively long service life for all areas of the bit head, so that the bit head is not prematurely damaged by component failures.

  In another embodiment, in order to avoid damage to the cutting element or hard material element during the coating process, or to avoid deformation of the mounting surface to which the cutting element or hard material element is attached, The protective covering layer is mounted at least a minimum distance away from the cutting element and / or the holding part in the region holding the hard material element. In particular, when the anti-wear coating layer is provided as armored welding, extremely high temperatures may occur in the welding region. The cutting element, the hard material element or its mounting surface on the holding part are exposed to high temperatures and are thus prevented from being damaged or deformed by a minimum spacing.

  In embodiments where a small torsional force transmitted to the bit head at the same time as high cutting performance can be obtained, the cutting edge of the cutting element is arranged in a direction along the central longitudinal plane (M) of the bit, A longitudinal plane of the longitudinal plane extends in the direction of the front side of the bit, in particular the cutting edge is arranged along the central longitudinal plane (M) of the bit.

  In a preferred embodiment of the invention, the cutting element has a leading surface on the front side, the leading surface is shaped in a bulging shape, in particular convex, and / or the leading surface faces the front side. Oriented with an edge with a first outer angle and / or a cutting edge with a cutting tip with a second outer angle and / or a flank It has an edge with a third outer angle and / or the outer angle is arranged in a direction along the second central longitudinal plane of the bit extending from the front side to the rear side. Due to the swollen lead-out surface, the cutting element is reinforced in such a way that the service life of the cutting element can be significantly increased, especially in areas that are strongly subjected to abrasive loads. The same is true for a lead-out surface with an edge projecting forward along the central longitudinal plane. Due to the swollen shape, the waste debris material is strongly transported to the ejection area. Due to the edge, the movement of the debris material additionally gains a side component, so that the debris material is present evenly distributed in the eject area. Due to the formation of the cutting tip, the bit enters relatively hard ground and rock relatively easily. At this time, the waste debris material which is not carried out can be pressed to the side by the flank with the outer edge. A cutting element with edges arranged along a central longitudinal plane extending from the front side to the rear side of the bit exhibits better cutting and removal results in a relatively hard material, whereas it is concave The shaped cutting element is better suited for soft ground and plastically deformable ground. Thus, a bit having a cutting element with an outer edge can be used, for example, even on ground frozen in winter, whereas a bit with an inflated cutting edge is used in summer.

  Unlike a bit with a rotationally symmetric bit head that tapers towards the tip, the bit according to the invention has a defined front and rear side. In order to keep the front side with the cutting element oriented in the feed direction during operation, in another embodiment the bit shank is formed as a round shank, the bit shank being in the shape of the bit holder Having at least one shape-coupling element suitable for cooperating with the coupling-compatible element, or a locking member that can be fixed to the bit holder can be arranged corresponding to the bit holder as the shape-coupling-compatible element, and the bit Can be fixed non-rotatably to the shape coupling corresponding element by the shape coupling element. In this way, the bit is held in the bit holder in a non-rotatable manner despite its circular bit shank. The bit can be held in the same bit holder as the known round shank bit, which preferably has a symmetrical bit head and rotates about the central longitudinal axis during operation. This allows the cutting drum to be fitted with a known rotating bit or a locked bit according to the invention in relation to the material to be crushed.

  In another embodiment, the bit head has a support on the side of the bit shank to lock the bit in its axial position and to protect the bit holder against intensive wear, The support is terminated by a support surface that extends beyond the bit shank in the radial direction. If comprised in this way, a support surface will be mounted in the end surface surrounding a bit accommodating part of a bit holder. As a result, a mounting surface having a large area can be obtained between the bit head and the bit holder, so that a large force exerted on the bit head in the axial direction can be transmitted to the bit holder without deformation of the mounting surface. it can. Since the waste debris material is guided to pass along the bit holder by the extension of the support, the wear action of the waste debris material on the bit holder can be kept small.

  The flow of waste debris material is critically influenced by the shape of the recesses in the bit head. In the embodiment in which the material finely crushed by the cutting element can be effectively carried out, the turning surface is used to form a turning surface extending from the ejection region to the front side of the bit head. Is descending in the direction of the bit shank from the central region of the bit head toward the front side of the bit head. The turning surface covers and protects the underlying support. Great mechanical protection is obtained when the turning surface is provided with an anti-wear coating.

  Next, the present invention will be described in detail with reference to the embodiments shown in the drawings.

It is a side view which shows the bit which crushes a relatively soft substance. It is a side view which shows the upper end part of the bit head of the bit shown in FIG. 1 provided with the cutting element. It is the perspective view which looked at the bit shown in FIG. 1 from the rear side. It is a side view which shows the 2nd bit which crushes a comparatively hard substance. It is the perspective view which looked at the 2nd bit shown in Drawing 4 from the back side. It is another perspective view which looked at the bit shown in FIG. 1 from the rear side. It is sectional drawing which shows a bit holder corresponding to the cross section shown in FIG. 1 and FIG. It is a figure which shows a part in the area | region of the locking member of the bit shown to FIG. 1 and FIG.

  FIG. 1 shows a side view of a bit 10 for crushing a relatively soft material, in particular an oil sand or other plastically deformable or sandy ground.

  The bit 10 includes a bit head 20 and a bit shank 40 formed integrally with the bit head 20, and the bit shank 40 is formed as a substantially cylindrical round shank 42. The bit head 20 has a support 27 on the side facing the bit shank 40, and this support 27 has shifted to the holding part 23. The holding part 23 forms a shovel-shaped recess 20.6 directed to the front side 20.1 of the bit 10 and the bit head 20. The bit head 20 is arranged along the shovel-shaped recess 20.6 in three areas indicated by the double arrows, namely the front cutting area 20.3, the middle ejection area 20.4 and the rear deflection. It is divided into areas 20.5. In the cutting region 20.3, two cutting elements 30 arranged side by side toward the front side 20.1 of the bit head 20 are fixed to the holding part 23, as can be clearly seen from the description in FIG. ing. In the ejecting region 20.4, two plate-like hard material elements 28 arranged side by side cover the holding part 23 located thereafter. The turning area 20.5 is provided with a turning face 24.5 provided with an anti-wear coating layer 29, which has a corresponding shape that is lightly bent to provide an ejection area. From the plane formed by the hard material element 28 of 20.4, it extends towards the front side 20.1 of the bit head 20. The diverting surface 24.5 is oriented such that the diverting surface 24.5 descends from the transition to the eject region 20.4 toward the front end of the bit head 20.

  Connected to the rear side of the cutting element 30 and the hard material element 28, the holding part 23 forms upper and lower side connecting surfaces 25.1, 25.2. As can be seen in FIGS. 1 and 3, the side connection surfaces 25.1, 25.2 are provided with an anti-wear coating layer 29. The side connection surfaces 25.1, 25.2 are connected to the cutting element 30 and the hard material element 28 at the side in the front region. The distance between the connecting surfaces 25.1, 25.2 on the opposite sides on both sides of the bit head 20 decreases towards the rear side 20.2 of the bit 10 and the bit head 20. Yes.

  As shown in FIGS. 1 and 2 on an enlarged scale, the cutting element 30 is substantially L-shaped with a fixing member 36 and an angle of the fixing member 36 relative to the rear side 20.2 of the bit head 20. And the additional portion 32 formed integrally. Toward the front side 20.1, the fixing member 36 can have a lead-out surface 37 shaped in a bulging shape, which leads to the outermost end of the cutting element 30 and thus of the bit head 20. It has shifted to the cutting edge 31 at the outermost end. A flank 33 that descends obliquely is formed by the additional portion 32 starting from the cutting edge 31, and the flank 33 is oriented in the direction opposite to the feed direction V of the bit 10. On the side opposite to the lead-out surface 37, the fixing member 36 has a contact surface 35, which is angled with respect to the support part 34 arranged on the opposite side of the flank 33. positioned. The contact surface 35 and the support part 34 are in contact with the contact area 24.2 and the support area 24.1 of the holding part 23 and are formed in this contact area 24.2 and the support area 24.1, for example by brazing. Are joined by a material joining type joint. Alternatively, the material-bonded joint can be formed by gluing. On the extended line of the flank 33, the holding part 23 has a connection surface 26.1, which likewise has an anti-wear coating layer 29, which is connected to the rounding region 26 of the holding part 23. Has moved to .2. Through this rounding region 26.2, the oblique orientation of the connecting surface 26.1 changes into an orientation extending along the direction of the central longitudinal plane M of the outer surface of the support 27.

  The cuboid-shaped hard material element 28 is directly connected to the cutting element 30 and is fixed to the front side 20.1 of the bit head 20. For this purpose, the hard material element 28 is connected on the rear side to the fixing plane 24.4 of the holding part 23 in a material-bonding manner, in this embodiment by brazing, or alternatively by gluing. For precise positioning of the hard material element 28, a step-shaped positioning edge 24.3 is provided between the contact area 24.2 and the fixing plane 24.4, and this positioning edge 24.3 is provided on the positioning edge 24.3. The hard material element 28 is in contact at its upper end face.

  The anti-wear coating layer 29 on the connecting surfaces 25.1, 25.2 on the side of the connecting surface 26.1 and the turning surface 24.5 is located at a minimum distance from the cutting element 30 or the hard material element 28. Yes.

  A terminal portion of the bit head 20 located on the side opposite to the cutting element 30 is formed by a cylindrical support body 27, and the support body 27 is integrally transferred to the bit shank 40. A conical centering that surrounds the cylindrical round shank 42 at the transition from the end-side support surface 27.1 projecting radially from the bit shank 40 of the support 27 to the round shank 42. A portion 41 is provided. A conical tapered region 43 is connected to the round shank 42, and a shape coupling element formed as a lock pin 44 is integrally formed in the tapered region 43. The lock pin 44 has a pin surface 44.1 on both sides and a rear side and a pin rounding 44.2 on the front side 20.1. The bit shank 40 is terminated on the end side by a disk-shaped end member 46, and this end member 46 is separated from the lock pin 44 by a groove 45.

  As further shown in FIG. 1, the bit 10 is held in a bit holder 50 via its bit shank 40. For better illustration, the bit holder 50 is shown in cross section.

  The bit holder 50 has a holding region 54 and a base portion 56 located on the opposite side to the bit head 20. The bit holder 50 has a cylindrical basic shape, and this basic shape is tapered by an inclined portion 53 in an area directed to the bit head 20. The inclined portion 53 transitions to an end surface 51 that is oriented laterally with respect to the central longitudinal axis of the bit 10 via a rounded chamfered edge. The support surface 27.1 is in contact. Toward the bit shank 40, the end surface 51 has a centering receiving portion 52 formed as an inclined portion that is aligned with the centering portion 41 of the bit 10. The centering portion 41 forms an end portion of the bit accommodating portion 55 disposed in the holding region 54 of the bit holder 50. The bit accommodating part 55 is formed as a cylindrical hole according to the outline of the round shank 42 of the bit shank 40.

  As can be seen from the perspective view seen from the rear side of FIG. 1 and FIG. 3, the base portion 56 of the bit holder 50 has a front wall 56.5 directed towards the front side 20.1, and a rear mounting. The opening 56.3 forms a partially enclosed hollow chamber 57 opened by the mounting opening 56.3 and towards the end side of the bit holder 50. The mounting opening 56.3 is defined by the end face 56.4 of the substantially semicircular front wall 56.5, which starts from the holding area 54 of the bit holder 50 and is formed on the base portion 56. It arrange | positions so that it may extend diagonally with respect to the front side 20.1 of the bit holder 50 toward a lower end part.

  The hollow chamber 57 itself is delimited by a substantially semicircular front wall 56.1 of the front wall 56.5 towards the front side 20.1, which in the side is attached to the mounting opening 56. Transition to two side wall surfaces 56.2, which are somewhat open and straightly extending towards .3. This is clearly shown in the cross-sectional view of FIG. 7 taken along the cutting line marked by VII.

  As further shown in FIG. 1, the lock pin 44 of the bit shank 40 is fixed on a lock member 60 shown in a cross-sectional view. The lock member 60 is held in the axial direction of the bit shank 40 by a clamp element 70 that engages with the groove 45 of the bit shank 40. The locking member 60 forms a shape coupling type coupling portion with respect to the bit holder 50 and the lock pin 44, and this shape coupling type coupling portion is a bit centered on the central longitudinal axis of the bit 10. Block 10 rotations. Therefore, the lock pin 44 is held in the through hole 64 of the lock member 60.

  The bit holder 50 is welded to the cutting drum (not shown) at its front side 20.1. For attachment to the bit holder 50, the bit shank 40 of the bit 10 is introduced into the bit receiving portion 55 of the bit holder 50, the lock member 60 is fitted into the lock pin 44, and the clamp element 70 is inserted into the groove 45. It is caught. The orientation of the lock member 60 is set by the outer contour thereof and the contour of the hollow chamber 57. Since the orientation of the bit 10 is also determined by the configuration of the lock pin 44 and the through hole 64 of the lock member 60, the front side 20.1 of the bit 10 faces the cutting drum, and consequently the feed direction V of the bit 10. The bit 10 is determined in the axial direction by the bit head 20 being mounted on the end surface 51 of the bit holder 50 with its support surface 27.1 and the clamping element 70 engaging the groove 45. As a result, the bit 10 formed as a round shank bit is held in the bit holder 50 in a non-rotatable manner.

  During operation, the bit 10 is moved through the ground to be cut by the rotation of the cutting drum in the feed direction V. At this time, first, the cutting edge 31 on the front side is engaged with the ground, and the ground is crushed finely. The ground is crushed and captured along a relatively wide line by a cutting edge 31 which is wider than the bit tip of a known round shank bit. The waste debris material thus peeled off is guided into the eject region 20.4 of the bit head 20 by imparting a convex shape to the lead-out surface 37 of the cutting element 30. There, the debris material is captured by the hard material element 28 and entrained in accordance with the rotation of the cutting drum. In particular, for non-viscous waste material such as rock or non-adhesive sand, the turning surface 24.5 prevents the waste material from flowing out of the recess 20.6. In the plastically deformable waste debris material, such waste debris material is guided from the cutting region 20.3 to the turning region 20.5 via the eject region 20.4 by the shovel shape of the recess 20.6. At this time, it is transformed into a spherical or roll-shaped coagulum. The material molded in this way is transported, for example, to a discharge part (Auswurf) in the recess 20.6, and from there is then transported out, for example, by a charge belt system (not shown).

  The surface of the bit head 20 that forms the recess 20.6 in the cutting region 20.3 and the ejection region 20.4 is formed by the cutting element 30 and the hard material element 28 in this embodiment. The surface extends substantially along the central longitudinal plane M of the bit 10. A perpendicular to the central longitudinal plane M extends in the direction of the front side 20.1 of the bit 10. In the region of the central longitudinal plane M, the bit head 20 has its maximum diameter. As a result, the cutting region 20.3 and the ejecting region 20.4 can be formed extremely wide in the transverse direction with respect to the feed direction V, thereby generating a high conveyance performance for waste debris material. Thus, the bit 10 is particularly suitable for cutting relatively soft materials such as oil sands.

  The cutting area 20.3 is subjected to the strongest mechanical load when the bit 10 is operated. Thus, in this region, the bit 10 is protected towards its front side 20.1 by a fixing member 36 with a leading surface 37 of the cutting element 30 made of a hard material, here a hard alloy. Due to the swollen shape of the fixing member 36, there is a maximum material strength of the cutting element 30 in the region of maximum wear, which increases with increasing distance to the cutting edge 31 and thus mechanical load. Decreases with decrease. Such optimized material use can reduce the manufacturing cost of the cutting element 30, which is mainly influenced by the material cost. By using two cutting elements 30 adjacent to each other, the force transmitted into the cutting element 30 and thus the risk of breakage thereof can be reduced compared to a single cutting element 30 having a relatively wide width.

  Via the flank 33 directed in the feed direction V, the additional part (Ansatz) of the cutting element 30 can be guided to pass along the ground of fixed position following the cutting edge 31. Since the flank 33 shifts to the connecting surface 26.1 oriented in the same direction without a large step, there is no engagement point for the waste debris material that passes and slides here as well. The cutting element 30 is fixedly connected to the holding part 23 by means of its contact surface 35 and its brazed joint at the support part 34. At this time, the force action on the cutting element 30 is performed almost in the direction opposite to the feed direction V, and as a result, acts on the boundary surface between the cutting element 30 and the holding portion 23 as a pressing force. Since a large tensile force acting on this boundary surface can be avoided in this way, the cutting element 30 is securely held by the holding portion 23. The connection surface 26.1 and the upper side connection surface 25.1 connected to the cutting element 30 on the opposite sides of the bit head 20 are wear-resistant formed as armor welding (Panzerschweissung). A coating layer 29 is provided. As a result, the cutting region 20.3 is completely prevented from being worn down to the minimum distance provided between the anti-wear coating layer 29 and the cutting element 30. In particular, the wear-preventing coating layer 29 avoids scraping of the region of the holding part 23 that connects to the cutting element 30 and thereby dissociating the cutting element 30 from the holding part 23.

  The ejection area 20.4 is protected by the hard material element 28 towards the front side 20.1. Since the eject region 20.4 is not subjected to a stronger load than the cutting region 20.3, the material thickness of the hard material element 28 is reduced compared to the material thickness of the cutting element 30. The hard material element 28 is coupled to the holding portion 23 by a material coupling type coupling portion formed by brazing. Since the lower side connection surface 25.2 connecting to the hard material element 28 and the turning surface 24.5 is also protected against increased wear as an anti-wear coating 29 by armor welding, This area behind the hard material element 28 is also not scraped off. The rear side of the holding part 23 is retracted from the remaining debris material by the rounding area 26.2 in the ejection area 20.4 and the turning area 20.5, so here the bit along the ground Only a relatively small wear load on the bit head 20 occurs during 10 sliding passes. In order to reduce manufacturing costs, the anti-wear coating layer 29 is not provided in this region.

  The mutual spacing between the upper side connection surfaces 25.1 located opposite to each other and between the lower side connection surfaces 25.2 located opposite to each other causes the cutting elements 30 or the hard material elements 28 to be separated. Since the starting point decreases toward the rear side 20.2 of the bit head 20, an undercut is formed. Thereby, the side connection surfaces 25.1, 25.2 do not form a point of action for waste debris material. This on the one hand reduces the wear of the side connection surfaces 25.1, 25.2 and, on the other hand, allows the bit 10 to be pulled relatively easily through the ground to be cut. As a result, the power required to drive the cutting drum is reduced and thus energy is saved.

  The turning zone 20.5 is subjected to the least load causing wear compared to the cutting zone 20.3 and the ejection zone 20.4. Accordingly, the anti-wear coating 29 provided on the turning surface 24.5 provides sufficient protection of the turning region 20.5. Therefore, expensive hard material elements can be omitted in the turning zone 20.5. Thus, the anti-wear treatment is tailored to different mechanical loads in the cutting zone 20.3, the ejection zone 20.4 and the turning zone 20.5 so that approximately equal service life is obtained for all zones. It has been. This avoids premature failure of the bit 10 based on premature wear in one region due to the structure. At the same time, the use of materials for particularly hard materials and the anti-wear coating 29 is optimized.

  The anti-wear coating layer 29 is brought close to the cutting element 30 and the hard material element 28 with a minimum spacing. This prevents the cutting element 30 or the hard material element 28 from being damaged or destroyed by the high temperatures generated during coating. Furthermore, it is avoided that the support area for the cutting element 30 and the hard material element 28 is deformed due to heat.

  The support body 27 formed in a substantially cylindrical shape covers the upper area of the bit holder 50 and prevents the upper area from being worn out at an early stage. This provides a significantly longer service life for the bit holder 50 and the easily replaceable bit 10 itself. The support surface 27.1 of the support body 27 arranged around the bit shank 40 forms a large mounting surface of the bit head 20 on the end surface 51 of the bit holder 50. As a result, this region In this case, it is possible to avoid the deformation caused by the force provided through the bit head 20.

  The bit accommodating part 55 has a diameter larger than the round shank 42 of the bit 10 by a predetermined play, so that the bit shank 40 can be easily inserted into the bit accommodating part 55 when installed. And can be easily removed again at the time of removal. The centering portion 41 cooperates with the centering mounting portion 52 to achieve accurate orientation of the bit 10 and the bit shank 40 with respect to the bit receiving portion 55.

  The bit holder 50 is formed to have a wall thickness around the bit accommodating portion 55 formed as a central hole in the holding region 54, thereby reliably receiving the lateral force transmitted through the bit shank 40. it can. For this purpose, the diameter of the bit holder 50 is enlarged by the inclined portion 53 starting from the end face 51 directed to the bit head 20. Since the inclined portion 53 guides the waste debris material that slides through along the bit holder 50 without an overhanging edge, the wear force is kept as small as possible in this enlarged region of the bit holder 50.

  The base part 56 of the bit holder 50 has its front wall 56.5 surrounding the formed hollow chamber 57 towards the front side 20.1. At this time, the outer contour of the front wall 56.5 is matched to the outer contour of the holding region 54 to be connected, so that the bit holder 50 can be inserted into a corresponding receiving part of the cutting drum and welded there. it can.

  Through the mounting opening 56.3, the locking member 60 can be pressed into the locking pin 44 during mounting and can be fixed together with the bit 10 by means of the clamping element 70. The bit 10 is prevented from rotating about its central longitudinal axis by a shape-coupled connection between the locking member 60 and the locking pin 44. Correspondingly, rotation of the locking member 60 about the central longitudinal axis of the bit 10 is locked by a second shape coupling connection between the locking member 60 and the base portion 56. At this time, the shape coupling type coupling portions between the lock member 60 and the lock pin 44 of the bit 10 and between the lock member 60 and the base portion 56 are formed as follows. That is, in this case, the lock member 60 can be introduced into the hollow chamber 57 only in the radial direction, and the bit 10 can be introduced into the through hole 64 of the lock member 60 only in one rotation direction. Can not be. The shovel-shaped recess 20.6 of the bit head 20 is thus always directed towards the front side 20.1, and thus towards the feed direction V.

  In order to remove the bit 10, the clamping element 70 is pulled out of the groove 45 and the locking member 60 is removed. The bit 10 can now be removed from the opening of the base part 56 facing the holding area 54, possibly using a removal tool.

  FIG. 4 shows a side view of the second bit 11 for crushing a relatively hard material. Also in FIG. 4, the same members are shown in the same way corresponding to FIGS.

  Unlike the bit 10 shown in FIGS. 1 to 3, the second bit 11 shown in FIG. 4 has only a cutting area 20.3 and an ejecting area 20.4. The holding part 23 is covered by a single cutting element 30 which is substantially L-shaped towards the front side 20.1 of the bit head 20 in the cutting area 20.3. In the extended portion of the fixing member 36 of the cutting element 30, a cuboid-shaped hard material element 28 is attached to the front side 20.1 of the holding portion 23 in the eject region 20.4 to be connected.

  Alternatively, two or more hard material elements 28 arranged side by side may be provided.

  As shown in FIG. 4, and in particular, as shown in the perspective view seen from the rear side of the second bit 11 in FIG. 5, the lead-out surface 37 is formed into a roof shape. The edge formed correspondingly is oriented along a central longitudinal plane of the second bit 11 extending from the front side 20.1 towards the rear side 20.2. The cutting element 30 is oriented obliquely with respect to the central longitudinal axis of the second bit 11 and is attached to the holding part 23 so that the edge is substantially directed in the feed direction V of the second bit 11. It has become. The flank 33 formed by the additional portion 32 is also formed in a roof shape, where the surface plane is oriented along the feed direction V. The edge of the flank 33 extending corresponding to the roof ridge is likewise arranged along the central longitudinal plane of the second bit 11 extending from the front side 20.1 towards the rear side 20.2. ing. As a result, a cutting edge 31 having a cutting tip 38 located on the central longitudinal plane is formed in the transition region from the lead-out surface 37 to the flank surface 33. In an alternative embodiment, the cutting area 20.3 may have two cutting elements 30 that are mirror-imaged, both cutting elements 30 being along a cutting edge extending in the central longitudinal plane. They are butted against each other.

  Connected to the flank 33 of the cutting element 30, the holding part 23 has a flat connecting surface 26.1, which is the same as the additional part 32 of the cutting element 30. Oriented in the direction. The connection surface 26.1 is partly provided with an anti-wear coating layer 29. At the rear end of the bit head 20, the connection surface 26.1 is bent on the rear surface of the bit head 20 extending at equal intervals with respect to the central longitudinal axis of the second bit 11. This rear surface transitions to the cylindrical region of the support 27 without an additional part.

  The rigid material element 28 is mounted somewhat towards the front side 20.1 of the ejecting area 20.4, tilted somewhat with respect to the central longitudinal plane M. The positioning edge 24.3 for positioning the hard material element 28 is formed by a step at the lower end of the ejection area 20.4, from which the bit head 20 is cylindrical toward the front side 20.1. The outer contour is made. The hard material element 28 is in contact with the positioning edge 24.3 at the end face.

  The bit head 20 of the second bit 11 does not have a recess 20.6 as in the case of the bit 10 shown in FIGS. The front surface of the holding portion 23 of the second bit 11 formed by the lead-out surface 37 of the cutting element 30 and the hard material element 28 starts from a cutting edge 31 arranged in the region of the central longitudinal plane M. , Guided toward the front side 20.1 of the bit head 20. As a result, the holding portion 23 of the second bit 11 has a significantly larger material thickness than the holding portion 23 of the first bit 10 shown in FIGS. The support 27, the bit shank 40, the locking member 60, the clamping element 70 and the bit holder 50 are equally configured if the functions for both bits 10, 11 are the same.

  The second bit 11 is particularly suitable for cutting hard, non-plastically deformable or non-sandy materials. Furthermore, the second bit 11 can be used on frozen ground, preferably in frozen oil sands, preferably in winter, whereas the bit 10 shown in FIGS. 1-3 has melted. Used on the ground.

  Due to the cutting tip 38 formed, the second bit 11 can also cut rock or frozen material. A relatively large force can be transmitted to the debris material by means of the reinforced holding part 23, and the bit head 20 is not damaged at this time, so that even hard materials are cut. Can do. By means of the roof-shaped lead-out surface 37 of the cutting element 30, the hard waste debris material is distributed laterally and then captured and carried out by the hard material element 28 in the ejection area 20.4. Therefore, the second bit 11 provides high cutting performance and high conveyance performance due to the hard and brittle material.

  FIG. 6 shows another perspective view of the bit 10 shown in FIG. 1 as viewed from the rear side. According to this drawing, the inside of the hollow chamber 57 of the bit 10 can be seen through the mounting opening 56.3.

  As shown in FIG. 6, the lock member 60 is inserted into the bit shank 40 (of which the end member 46 is visible), and is held by a clamp element 70 inserted into the groove 45 of the bit shank 40.

  The locking member 60 has a substantially U-shaped outer contour, with which the locking member 60 contacts the front wall surface 56.1 and the side wall surface 56.2 of the correspondingly shaped front wall 56.5. ing. By this U-shape and contact with the side wall surface 56.2, the locking member 60 is locked against rotation about the central longitudinal axis of the bit 10. The lock member 60 has a base body 61 in which a web 63 is integrally formed. The web 63 surrounds the clamp accommodating part 62 except for the region directed in the direction of the attachment opening 56.3 of the bit holder 50. The clamp element 70 is disposed in the clamp housing portion 62 and is clamped immovably in the groove 45.

  The clamp element 70 has a rectangular basic shape and is formed in a plate shape. A clamp region 73 surrounded by two clamp jaws 74 is provided starting from the front end face, and the groove 45 of the bit shank 40 is clamped in the clamp region 73. Starting from the clamp region 73, an enlarged clamp slit 72 is provided at the center of the clamp element 70, and this clamp slit 72 terminates at a curved portion 71 to which the clamp jaw 74 is coupled. The clamping element 70 is preferably manufactured from a spring elastic material, in particular made of spring steel.

  The bit shank 40 of the bit 10 is introduced into the bit accommodating part 55 of the bit holder 50 for attachment. Thereafter, the locking member 60 is inserted into the bit shank 40 through the mounting opening 56.3 and fixed by the clamping element 70. For this purpose, the clamping area 73 of the clamping element 70 is pressed against the groove 45, and both clamping jaws 74 are pressed away from each other along the clamping slit 72, whereby the bit shank 40 is then moved into the groove 45. Can move around tightly.

  FIG. 7 shows a cross-sectional view of the bit holder 50 corresponding to the section VII in FIGS. 1 and 4.

  By means of the front wall 56.5 of the base part 56, a semicircular front wall surface 56.1 is formed together with a side wall surface 56.2 extending linearly connected to the front wall surface 56.1 on both sides. The outer contour of the substantially U-shaped locking member 60 is adapted to the shape of the front wall surface 56.1 and the side wall surface 56.2, whereby the locking member 60 is rounded directed towards the front side 20.1. Two locking surfaces 65.1 that contact the front wall 56.1 at the part 65.2 and that are connected to the rounded part 65.2 at the side, contact both side walls 56.2 of the front wall 56.5. Yes.

  The contour of the through hole 64 of the lock member 60 is matched with the outer contour of the lock pin 44. For this purpose, the through-holes 64 each have one through-hole surface 64.1 toward the rear side 20.2 and on the side, and each of these through-hole surfaces 64.1 has a lock pin 44 respectively. In contact with the pin surface 44.1. The through hole 64 has a concave through hole rounded part 64.2 toward the front side 20.1, and this through hole rounded part 64.2 contacts the pin rounded part 44.2 of the lock pin 44. doing.

  The stepped cutting shape shown in FIGS. 1 and 4 makes it possible to recognize the end region of the clamp receiving part 62 together with the curved part 71 of the clamp element 70 toward the mounting opening 56.3.

  The orientation of the locking member 60 is fixedly determined by the adaptation of the outer contour of the locking member 60 to the shape of the front wall surface 56.1 and the side wall surface 56.2. The rotation of the locking member 60 about the central longitudinal axis of the bits 10, 11 is locked by the locking surface 65.1 that contacts the side wall surface 56.2.

  The lock pin 44 of the bit shank 40 can also be introduced into the through hole 64 of the lock member 60 only in one orientation, based on the pin round part 44.2 and the corresponding through hole round part 64.2. . The orientation of the bits 10, 11 and thus the orientation of the bit head 20 is determined thereby. The rotation of the bits 10, 11 about the bit longitudinal axis is locked by the pin surface 44.1 in contact with the through-hole surface 64.1.

  FIG. 8 is a partial cross-sectional view of the bits 10 and 11 shown in FIGS. 1 and 4 in the region of the lock member 60. The lock member 60 is formed of a base body 61 that surrounds the lock pin 44, and the base body 61 forms an abutment surface 61.1 toward the holding region 54 of the bit holder 50. The abutment surface 61.1 is arranged at a small distance from the corresponding corresponding surface 54.1 of the holding region 54, which is arranged around the bit receiving part 55 in the radial direction. A guide web 66 is integrally formed on the base body 61 so as to directly surround the through hole 64. The guide web 66 has an inner contour that follows the lock pin 44 and an outer contour that is the bit holder 50. It follows the bit accommodating portion 55. The guide web 66 is introduced into the end region of the bit accommodating portion 55, whereby the lock member 60 is fixed in the radial direction. In order to avoid tilting during installation, the guide web 66 has a chamfered portion 66.1 around it. The lock pin 44 is introduced into the through hole 64 of the lock member 60, and together with the lock member 60, the lock pin 44 forms a shape coupling type coupling portion that prevents the bits 10 and 11 from rotating.

  The base body 61 has an annular chamfered portion 61.2 toward the outer peripheral portion, and this chamfered portion 61.2 is a protruding portion of the base portion 56 of the bit holder 50 toward the front wall 56.5. Located opposite to 56.6.

  A web 63 is integrally formed on the base body 61 on the side of the lock member 60 that faces the holding region 54. The web 63 surrounds the clamp housing 62 except for the region directed towards the mounting opening 56.3 of the bit holder 50. The clamp element 70 is disposed in the clamp housing portion 62 and is clamped immovably in a groove 45 formed between the lock pin 44 and the end member 46.

  Thereby, the locking member 60 locks the rotational movement of the bits 10, 11 and cooperates with the clamping element 70 to lock the movement of the bits 10, 11 in the axial direction, except for slight play. This slight play occurs due to the small spacing between the abutment surface 61.1 and the corresponding surface 54.1. This play facilitates the installation or removal of the bits 10, 11 and compensates for errors. By means of the contact surface 61.1, a tensile force acting on the bits 10, 11 in the axial direction can be transmitted to the bit holder 50 via the corresponding surface 54.1. The clamp element 70 enables quick installation and removal of the bits 10 and 11. Since the clamp element 70 is accommodated in the clamp accommodating portion 62 of the lock member 60, the clamp element 70 is sufficiently protected against damage caused by the invading debris material.

  The bit holder 50 can accommodate the bits 10 and 11 whose rotation is locked, or can accommodate a round shank bit whose rotation is desired. In the latter case, for example, the lock pin 44, the lock member 60 and the clamp element 70 are omitted, and instead of these members, a known holding element for locking the movement of the round shank bit in the axial direction can be provided. it can. The cutting drum can be provided with a wide variety of bits 10 and 11 depending on the field of use.

Claims (13)

Bits (10, 11), in particular round shank bits used in cutting drums, comprising a bit head (20) and a bit shank for holding the bits (10, 11) in a bit holder (50) ( 40), and the bit head of the bit (10, 11) has at least one cutting area (20.3), in the bit (10, 11),
Connected indirectly or directly to the cutting area (20.3), a planar and / or concave ejection area (20.4) is arranged in the central area of the bit head (20). Bits (10, 11), characterized in that   The cutting area (20.3) is oriented in the feed direction (V) direction of the bit (10, 11) at the end of the bit head (20) opposite to the bit shank. Having at least one cutting element (30) made of a hard material, in particular of a hard alloy, attached to the front side (20.1) and / or said ejecting area (20.4) is particularly hard Having at least one plate-shaped hard material element (28) made of alloy, said hard material element (28) being connected to said cutting element (30) indirectly or directly; The bit (10, 11) according to item 1.   A turning area (20.5) is disposed indirectly or directly in the eject area (20.4) of the bit head (20), and the turning area (20.5) Extending toward the front side (20.1) of the bit (10, 11), by the cutting area (20.3), the ejecting area (20.4) and the turning area (20.5), 3. Bit (10, 11) according to claim 1 or 2, wherein an excavator-shaped recess (20.6) directed towards the front side (20.1) of the bit (10, 11) is formed. .   The bit head (20) has a holding part (23), and the holding part (23) is arranged in the cutting area (20.3) and the ejecting area (20.4), In the cutting area (20.3) and / or the ejection area (20.4), the holding part (23) is connected to side connection surfaces (25.1, 2) disposed on both sides of the holding part (23). 25.2), and the interval between the connecting surfaces (25.1, 25.2) is such that the front side (20.1) is the starting point and the rear side (20 Bit (10, 11) according to any one of claims 1 to 3, which decreases towards .2).   The cutting element (30) includes a fixing member (36) oriented toward the front side (20.1) of the bit (10, 11), and the bit (10, 11) from the fixing member (36). ) And the additional portion (32) oriented toward the rear side (20.2), the cutting element (30) at the outermost end of the bit head (20) A cutting edge (31) is formed, and the cutting element (30) forms a lead-out surface (37) from the cutting edge (31) toward the fixing member (36), and the additional portion Bit (10, 11) according to any one of the preceding claims, wherein a flank (33) is formed towards (32).   The fixing member (36) forms a contact surface (35), and the additional portion (32) forms a support portion (34), and the cutting element (30) uses a material coupling type coupling portion. Between the contact surface (35) and the contact area (24.2) and / or between the support part (34) and the support area (24.1) of the holding part (23). 6. Bit (10, 11) according to claim 5, held in part (23).   The bit head (20) is particularly armored by an anti-wear coating (29) in the cutting area (20.3), the ejecting area (20.4) and / or the turning area (20.5). Bit (10, 11) according to any one of claims 1 to 6, which is covered by welding.   The anti-wear coating layer (29) is spaced from the region of the cutting element (30) and / or the holding part (23) holding the hard material element (28) by at least a minimum spacing. 8. Bit (10, 11) according to claim 7, which is mounted.   The cutting edge (31) of the cutting element (30) is arranged in a direction along the central longitudinal plane (M) of the bit (10, 11), and the surface of the central longitudinal plane (M) A perpendicular extends in the direction of the front side (20.1) of the bit (10, 11), in particular the cutting edge (31) along the central longitudinal plane (M) of the bit (10, 11). Bits (10, 11) according to any one of claims 5 to 8, which are arranged.   The cutting element (30) has a lead-out surface (37) on the front side, the lead-out surface (37) being shaped in a bulging shape, in particular in a convex shape, and / or the lead-out surface (37). ) Having an edge with a first outer angle directed towards the front side (20.1) and / or the cutting edge (31) with a second outer angle And / or the flank (33) has an edge with a third outer angle, and / or the outer angle is the front side (20. 1. The arrangement according to claim 1, arranged in a direction along a second central longitudinal plane of the bit (10, 11) extending from 1) towards the rear side (20.2). The bit (10, 11) according to item 1.   Said bit shank (40) is formed as a round shank (42), said bit shank (40) being at least one suitable for cooperating with a shape coupling corresponding element of said bit holder (50). A lock member (60) which has a shape coupling element or can be fixed to the bit holder (50) as a shape coupling corresponding element and can be arranged correspondingly to the bit (10). 11. A bit (10, 11) according to any one of claims 1 to 10, wherein said shape coupling element is non-rotatably fixable to said shape coupling corresponding element by said shape coupling element.   The bit head (20) has a support (27) on the side of the bit shank (40), and the support (27) protrudes beyond the bit shank (40) in the radial direction. 12. Bit (10, 11) according to any one of the preceding claims, terminated by a supporting surface (27.1).   A turning surface (24.5) extending from the ejection region (20.4) to the front side (20.1) of the bit head (20) is formed using the turning region (20.5). The turning surface (24.5) starts from the central region of the bit head (20) and moves toward the front side (20.1) of the bit head (20). 13. Bits (10, 11) according to any one of claims 3 to 12, which are descending in the direction of).

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