CN1282817C - rock drill - Google Patents

Abstract

This invention concerns a rock drill which has a V-shaped cutting plate (5) on its end face. To reduce the load on the carbide-tipped cutting plate and increase drilling performance, particularly in concrete, the flanks (10) are subdivided into sections (11, 12) to permit a narrower design of the drill head.

Description

rock drill

technical field

The invention relates to a rock drilling machine.

Background technique

A conventional rock drilling machine comprises a drill shank and a drill bit into which a cemented carbide part is inserted (shown in Fig. 1 of EP 0452255B1), the side view of which cemented carbide part presents a roof shape. The above-mentioned cutting elements have cutting edges or rake faces, on either side of the roof-shaped front end, based on a wedge shape, and in each case a top cutting edge. The position of the cutting edge now deviates laterally from the longitudinal center plane of symmetry, so that a so-called chisel point is produced (see Figure 2 of EP 0452255B1).

Usually the flank (flank) behind the end cutting edge in the direction of rotation has a side rake angle of about 20°-30° as opposed to a conventional 60° cutting edge angle or rake angle, which is relative to Measured in a plane perpendicular to the longitudinal axis of the rock drilling machine.

All show the design of such cutting insert in Fig. 2 to 4 of DE 8104116U1 and Fig. 1 of DE2912394A1. Some of these drilling tools have auxiliary cutting inserts or corresponding pins for the feeding of the drill bit.

The roof-shaped cutting insert made of cemented carbide can completely penetrate the drill bit over its entire diameter, forming a transverse projected length which forms its nominal diameter. If there are no auxiliary cutting inserts or corresponding pins, the transition area from the drilling spiral to the drill head is designed as a support area for the cutting inserts. In this case, in order to prevent its movement, the carbide cutting head is supported laterally inside the drill by a suitable large-volume support body, and the blocking surface is used for the removal of cuttings formed at the front end.

In EP-A 0353214 a kind of drilling tool with cemented carbide insert is disclosed, and this drilling tool is used for drilling rock. In order to create a better brazed connection between the tool body and the carbide insert, additional carbide sides are provided, into which the carbide body is inserted. In this case, the cemented carbide has a symmetrical structure with respect to its longitudinal center plane, providing sides with different end angles which effectively improve the brazing connection. No differentiation between the different rakes and sides is provided in this tool.

Contents of the invention

The object of the present invention is to improve said rock drilling machine in order to increase its drilling capacity in concrete. At the same time, reduce the load on the carbide cutting head.

According to the invention, a rock drilling machine is proposed with a drill shank and a drill bit, which has at least one cutting blade on its front end pointing in the feed direction, the cutting blade having at least one cutting blade arranged on the front end of the cutting blade. Edge, characterized in that it has a rake face with a corresponding negative rake angle α and behind the end cutting edge has a side face with a corresponding side rake angle β, wherein the side face is divided into at least two sides portion, and wherein a single rake face is provided, the rake face angle α adjoining the cutting edge is greater than the side rake angle β1 of the first side portion adjoining the cutting edge.

According to the invention, a rock drilling machine is proposed with a drill shank and a drill bit, which has at least one cutting blade on its front end pointing in the feed direction, the cutting blade having at least one cutting blade arranged on the front end of the cutting blade. Edge, characterized in that it has a rake face with a corresponding negative rake angle α and behind the end cutting edge has a side face with a corresponding side rake angle 1β, wherein the cutting insert has a single rake inclined surface, and the rake face angle α is between 60° and 80°, wherein the cutting insert is embedded in the drill such that the support body of the drill bit on both sides of the cutting insert has an outer contour that leads to the cutting on the sidewall of the blade without forming an end stop surface.

According to the invention, a rock drilling machine is proposed with a drill shank and a drill bit, which has at least one cutting blade on its front end pointing in the feed direction, the cutting blade having at least one cutting blade arranged on the front end of the cutting blade. Edge, characterized in that it is provided with a rake face with a corresponding negative rake angle α and behind the end cutting edge with a side face with a corresponding side rake angle β, wherein, in order to reduce the rake face in the plane of the tool The length 1 of the chisel tip in the view, the rake face of the cutting insert and/or the width of a second side part in plan view of the drilling tool increases towards the drilling point.

According to the invention, a rock drilling machine is proposed with a drill shank and a drill bit, which has at least one cutting blade on its front end pointing in the feed direction, the cutting blade having at least one cutting blade arranged on the front end of the cutting blade. Edge, characterized in that it has a rake face with a corresponding negative rake angle α and behind the end cutting edge has a side face with a corresponding side rake angle β, wherein the side face has a convex arch shaped profile and wherein there is provided a single rake face whose rake angle α is greater than the side rake angle β1 of the convex arched profile adjoining the sides of the cutting edge.

Compared with known drilling tools, the drilling tool according to the invention has the advantage that the drilling tool can penetrate deeper into the concrete since the cutting edge is not so blunt. This directly results in faster drilling. The impact energy acting on the drilling tool is not transferred to a conventional blunt carbide cutting head; instead the impact energy is converted into drilling capacity more efficiently by an elongated drill overall. Therefore, smaller tool sizes can be used in larger hammer drills without these smaller size tools being damaged. Due to the design of the front end of the carbide insert according to the invention, the load on the carbide cutting head itself is reduced.

A main basic idea of the present invention is to change the sides of the cemented carbide cutting head, and arrange the sides on the rear of the rake faces, eliminating the risk of cutting edge breakage. The invention is achieved in that each side is divided into at least two side parts, which for example may have the same width, where the side part directed to the side wall of the cemented carbide cutting head may for example have a lateral inclination, which The side rake angle is approximately twice that of the first side portion directed towards the cutting edge. In this way, the sides are made tapered so that the carbide cutting head appears tapered in side view directed towards its narrow end. Therefore, in a drilling tool, the shape of the carbide cutting head is sharper, which can drill into the material being drilled with lower resistance, so that the impact energy can produce faster drilling.

In a particular form of the invention, a conventional cemented carbide cutting element has on each side a second side portion which is substantially bisected in its upwardly projected length. However, the side parts can also be designed with different projected lengths and different inclination angles.

The improvement of the present invention to the rake face has an increased rake face angle of greater than 60°, preferably about 70°, compared to the conventional embodiment. At this time, according to the optimization requirements of the drilling tool, the rake surface can be designed to be flat or concave or convex. It is important here that the carbide cutting head transitions to the support surface in a tangential or linear manner. Whereas previously it was determined that a further increase in rake face angle and a sharper design of the carbide cutting tip would increase the risk of carbide tip breakage, extensive testing has shown improved chip evacuation during drilling Increased load capacity.

In this respect, too, a widening of the rake face in the direction of the central axis of the rock drilling machine can be seen, since the width of the chisel point is thereby reduced.

In a modified form of the present invention, the cemented carbide cutting head with a second side inclination of the present invention is integrated with a drill bit, the transverse support body of the cemented carbide cutting head of the drill is designed to be very slender And also tapered. In contrast to conventional drilling tools with bulky end support surfaces, the lateral support surfaces are designed as conical as possible lateral surfaces, for example whose outer contour is concave or arched or even smooth Flat, this design gives a drill with a carbide cutting tip a sharply tapered, arrowhead-shaped side view. At this time, it is particularly suitable if its outer contour is designed to be planar or convex or concave. Into the rake face and on all sides of the carbide cutting component. Viewed from the narrow end of the cemented carbide cutting element, this results in a flat or inwardly arched surface, which merges at least partially into a rake or hard edge in its upper region in a tapered manner. Sidewalls or sides of an alloy cutting component. In turn, end blocking surfaces are avoided. The size of this drill bit also achieves the desired effect with conventionally designed cutting inserts.

Description of drawings

The invention and its advantages will be described in more detail below with reference to the embodiments shown in the accompanying drawings, which include:

Fig. 1 is a perspective view of a drill bit of a drilling tool according to a first embodiment of the present invention,

Fig. 2 is a side view of the tool of the present invention seen from the A direction in Fig. 1, wherein only the right half of the cutting blade with a roof shape in Fig. 1 can be seen,

Figure 3a shows a conventional drilling tool, compared with the tool shown in Figures 1 and 3b, to show the prior art,

Figure 3b shows a conventional drilling tool, in contrast to the tool shown in Figure 2,

Fig. 4 shows another embodiment of the drilling tool of the present invention, the geometry of the drill bit is changed,

Figure 4a is an enlarged view of Figure 4 at a ratio of 5:1,

Fig. 5 is a side view of the embodiment shown in Fig. 4,

Figure 5a is a plan view of the embodiment shown in Figure 5,

Figures 6a-c illustrate other implementations of the embodiment shown in Figure 5a, and

Figure 7 is a perspective view of the tool shown in Figures 4 and 5 .

Detailed ways

In a first embodiment of the invention, the rock drilling machine 1 has a drill shank 2 (shown only approximately) and a drill bit 3, on the front end 4 of the drill bit 3 pointing to the feed direction 16 there is a cutting blade 5, from which Viewed across the width of a drill bit of roof-shaped design, the cutting insert 5 extends over its diameter D1. The cutting insert 5 has cutting edges or rake faces 6, 6' on both sides of its roof-shaped design, which are substantially wedge-shaped, form an angle γ in the direction of rotation 8, and have a negative rake angle α and form Cutting edges 7, 7' on the front end.

The drilling tool shown in FIG. 1 is rotated counterclockwise in the direction indicated by arrow 8 about the longitudinal axis of symmetry 9 of the tool.

In the conventional drilling tool shown in Figures 3a and 3b, the so-called bit flanks 10, 10' are located on the rear face of the respective rake face 6, 6', with a side rake angle β of the order of 20° to 30° . In this case, lower values apply to drilling tools with a smaller nominal diameter (eg ≦12 mm), and higher values apply to drilling tools with a larger nominal diameter. Rake Angle of Conventional Tool

特别是β1＝20°～30°。这里，较小的数值仍是适用于≤12mm的标称直径，而较大的数值适用于大于此值的标称直径。第二侧面部分12的第二侧倾角β2为

特别是β2＝60°。在此情形下，侧倾角β1、β2是相对于一垂直于钻头轴线9的平面13测得的。According to the invention, the known drill side 10 , 10 ′ is divided into two side parts 11 and 12 . At this time, the first roll angle β1 of the first side portion 11 is

In particular, β1 = 20° to 30°. Here, the smaller value is still applicable to the nominal diameter ≤ 12mm, while the larger value is applicable to the nominal diameter larger than this value. The second side inclination angle β2 of the second side portion 12 is

In particular β2 = 60°. In this case, the side inclination angles β1, β2 are measured with respect to a plane 13 perpendicular to the axis 9 of the drill bit.

的侧倾角的相对平坦的侧面10、10’由在β2处的第二侧面部分12的增加的倾斜使其被设计成更尖锐侧倾角。因此，硬质合金的切削刀片5的前端变得更细长。Comparing Figures 1 and 3a and Figures 2 and 3b, it can be seen that the cutting insert 5 is sharpened by dividing the known side face 10 into two side parts 11 and 12, i.e. the prior art has

The relatively flat sides 10, 10' of the roll angle are designed with a sharper roll angle by the increased inclination of the second side portion 12 at β2. Therefore, the tip of the cemented carbide cutting insert 5 becomes more slender.

Another alternative is a similar geometric design with more than two side sections (polyline) or as a convex surface, which represents the extreme case of polyline.

It can also be seen from FIGS. 1 and 2 that the first side portion 11 connected to the end cutting edge 7 has a projected length S1 in the plane 13, and the connected second side portion 12 has a projected length S2, the sum of which A length b is defined. The ratio S1:S2 can be varied according to the actual application, and its choice should also be coordinated with the projected length S3 of the rake surface 6 . For example, S1 could be $S1\≅(0.4~0.7)\×b.$

The overall width of the cutting insert 5 is denoted by B, B=S1+S2+S3.

As shown in FIG. 2 , the position of the end cutting edge 7 between the side face 11 and the rake face 6 of the cemented carbide cutting head 5 is at a distance from the longitudinal center plane 14 of the cutting insert 5 . At this time, the projected length S3 of the rake surface 6 is about 1/3 to 1/6, especially 1/5, of the total width B of the cutting insert 5 .

As can be seen from the prior art views of Figures 3a and 3b, a larger volume of supports 15 and 15' are provided at the sides of the cutting insert 5 to avoid displacement of the cutting insert 5 during loading. The supports 15 and 15' are preferably obtained by a milling or drilling, grinding operation on the drill bit 3, at this time, on either side of the cemented carbide cutting insert in the drilling direction 16 wide Surface portions 17, 18 which, in the prior art, constitute blocking or retarding surfaces for the material to be drilled.

In a modified form of the invention, these support bodies 15 and 15' have a pointed cone shape by grinding, so that the side wall parts 19, 19 " are obtained in the drill bit. That is, the outer contour line in FIGS. Parts 19, 19' are designed to be two-dimensional to a large extent, and in particular can be cylindrical, or concave, or even flat, so that no end stop surfaces are formed. From Fig. 2, it is best to choose a concave design of the outer contour line 19, 19' of the inner support body of the drill, and to introduce the hard metal tangentially or asymptotically in the area pointing to the front end The side wall 20 of the cutting head 5. This results in the sharp conical arrangement of the drill bit and cutting piece shown in Figure 2, which is more conducive to the penetration of the drill bit and cutting piece into the concrete, because the front-facing The stagnation surface is substantially reduced or completely eliminated. Preferably the same modification is carried out for the additional surface portion 12 of the second side, so that the lateral support has an arrowhead-like taper relative to the carbide cutting insert Structure. The top transition region 21 between the support body 15 and the cutting insert 5 extends approximately tangentially.

Thus, the supporting side walls 19, 19' of the drill form a side which is curved or arched or cylindrically arched in shape, ie a concave outer contour.

这符合前倾角的常规的数值范围。In the embodiment shown in Figures 1 and 2, the magnitude of the rake angle α (also referred to as the rake angle) can be

This corresponds to the conventional value range for the rake angle.

如果事先已经发现一个大于60°的前倾角会导致磨损的增加，特别是还增加了硬质合金切削头断裂的危险，则在本发明中使用这样一前倾角之前最好要经过仔细考虑。In another embodiment shown in Figures 4 and 5, the negative rake angle α of the selected rake face 6 is between 60° and 80°, in particular

If it has been previously found that a rake angle greater than 60° leads to increased wear and, in particular, also increases the risk of fracture of the cemented carbide cutting head, it is best to carefully consider before using such a rake angle in the present invention.

Generally, there are many difficulties in machining acute angles in cemented carbide manufacturing. On the one hand, improper shrinkage of the blank is the cause of premature failure of the process. On the other hand, in the case of machining acute angles, the loading force of the extrusion and sintering dies is also high, making the possibility of fractures during the manufacturing process high.

The new grades of cemented carbide are harder and thus have increased wear resistance, but their toughness is similar to that of the previous grades, which naturally leads to a reduction in their wear resistance, but is still estimated to present a high risk of fracture.

Surprisingly, however, the test results show that, even with previous grades of cemented carbide, if the impact energy in the rock is converted in an optimal manner and the power loss of the drill bit is reduced, wear and thus fracture despite increased rake angle The danger does not increase either. Such an arrangement is further advantageous because cuttings can be optimally removed from the drilling point if there are no blocking surfaces blocking the transport of cuttings to impede removal of cuttings. Therefore, if the cemented carbide bit is embedded in the drill bit in a certain way, a drilling tool with a sharp taper is obtained, which helps cuttings to be transported from the cemented carbide bit into the chip flute, thus No additional friction occurs in the area of the drill bit or in the area of the carbide cutting head. The formation of a second or larger clearance angle also has a positive effect on this.

Another problem is the design and design of modern drilling machines or percussion drilling machines, the impact power of which has been greatly increased. The percussion drills of the old construction type only have a splitting effect when drilling rocks, while the percussion drilling rigs of the new construction type can penetrate more or less in the rock. This is particularly advantageous if the impact surface is to be kept as small as possible and the drilling point as fine as possible.

These findings have led to a form of drilling tool according to the present invention, and in particular an improvement to the drilling tool shown in FIGS. 4 to 7 .

同时，支撑硬质合金切削头的侧壁25、25’渐近线地或成切线地合并入前倾面6内，以便得到一细长的、没有妨碍清除岩屑的阻滞表面的钻头。As shown in Figure 4 and the enlarged Figure 4a, the forward tilt angle α is made α>60°, especially

At the same time, the side walls 25, 25' supporting the carbide cutting head merge asymptotically or tangentially into the rake face 6 in order to obtain a slender drill bit without stagnation surfaces hindering the removal of cuttings.

特别是 并具有一侧面角或间隙角

特别是 此时，第二侧面部分12渐近线地或成切线地合并入另一侧壁26、26’内，以便在该侧也形成一相当细长的、没有妨碍清除岩屑的阻滞表面的钻头。侧壁25、26和25’、26’分别被中断线27分离(如图5和7所示)。Behind the cutting edge 7 there are again two side portions 11, 12 with a side or clearance angle

in particular and have a flank or clearance angle

in particular At this point, the second side portion 12 merges asymptotically or tangentially into the other side wall 26, 26', so that on this side also a rather elongated, non-blocking surface that hinders the removal of cuttings is formed. drill. The side walls 25, 26 and 25', 26' are respectively separated by a break line 27 (as shown in Figures 5 and 7).

It can be seen in FIG. 4 a , which enlarges FIG. 4 at a scale of 5:1, that the side parts 11 , 12 and the rake face 6 are projected into the horizontal plane 13 , forming the lengths S1 to S3 . The actual lengths of the side portions 11, 12 and the rake face 6 are respectively obtained by dividing the projected lengths S1 to S3 by the cosines of the respective angles β1, β2 and α.

In addition, the parts in FIGS. 4 to 5 that are the same as those in FIGS. 1 to 2 are denoted by the same numerals.

A side view of the broad side of the cutting insert 5 is shown in FIGS. 5 and 7 . The side portions 11, 12 can be seen in the right part of the figure, and the rake face 6 can be seen in the left part of the figure, together with the respective side wall portions 25', 26' extending tangentially towards these surface parts. Cuttings cut by the rake face 6' are discharged from the side wall portion 25' at the front end of the rake face 6' into the flutes 22 below (see perspective view in Fig. 7).

Due to the eccentric arrangement of the roof-shaped design of the cutting insert 5 and the rake face 6 and the side parts 11, 12, respectively, relative to the central plane 14, a so-called chisel tip 24 is obtained in the region of the center point 23 of the drill bit, as shown in the plane of FIG. 5 a shown in the view. Due to its central arrangement in the region of the drilling point 23, the chisel tip 24 has practically no peripheral speed and thus functions like a single-point drilling tool. Therefore, a particularly advantageous improvement of the present invention consists in keeping the length 1 of the chisel tip 24 as small as possible so that the action of the chisel tip 24 is concentrated on one point as much as possible.

To improve this, each rake face 6, 6' shown in Figures 6a and 6b is designed such that its width (as seen in plan) increases towards the drilling point 23 (shaded area F in the figures). This results in a reduction in the size of the chisel point 24, ie the length 1 is shortened. If the width increase towards the drilling point 23 is adopted at both rake faces 6, 6', the length of the chisel point in the plan view shown in Fig. In the region of point 23 actual point contact is obtained. In an ideal situation l≈0.

In FIG. 6 a the cutting insert 5 is shown having a first side portion 11 and a second side portion 12 as described with respect to FIGS. 1 , 2 and 4 and 5 . In FIG. 6 b, only one side 10 is shown symbolically, but also has a shortened chisel tip 24 due to the aforementioned fact.

Due to the aforementioned fact, the width of the second side portion 12 is likewise increased towards the center (as seen in plan view), so that the length 1 of the chisel tip 24 is further reduced (shaded area F in the figure). In Fig. 6c this is shown symbolically by an edge 28, 28' Ideally, this would again lead to actual point contact in the region of the drill point 23 . In Fig. 6c, the rake face 6, its width as shown in plan view, is designed parallel to the outer surface.

According to the method according to the invention, an optimum drill bit geometry is obtained with an optimum drilling rate and optimum cuttings removal. In particular, the method of the invention results in an elongated drill bit whose rake angle α has been increased compared to conventional drill bits and which provides two side portions. Of course, instead of two side sections, multiple side sections could be used if desired, which creates a polyline type. The side 10 can also adopt a convexly arched outer contour, which represents a type of "extreme polyline". The conical configuration of the cutting insert with a smooth transition into the side wall of the drill is decisive. On the one hand, a passage which is as wide as possible can be opened by such a slender drill bit, and the cuttings produced are unlikely to bring resistance. A slender bit also does not reduce the life of the drilling tool. With the method of the invention, opposites are very possible. This is mainly explained by the fact that the enormous impact energy of the power tool can be transmitted into the rock in a more efficient manner, with the result that the tool is protected. Tests have shown that an optimum drilling capacity and tool life are obtained when the cutting edge angle and the bit tool face meet each other tangentially, a factor that can be applied to both the rake angle and the clearance angle.

There are also other advantages if the rake face 6 is designed slightly concave, ie rounded. This applies in particular where increased cutting capacity is required within the reinforcement plate. The radial curvature produces coarser cuttings, ie the overall cutting effort is reduced, which also extends tool life.

An advantage of a convex cutting insert with a convex rake face 6 is that the convex cutting insert allows the use of smaller drill bits. However, the stability of the entire tool must also be considered here. Although the drilling capacity can be greatly increased compared with the above-described embodiment, the risk of bit breakage is also increased. In special cases, however, such an embodiment is quite suitable, especially for soft or wet rocks. However, for harder concrete or thicker rare earth or smooth reinforcement plates, it is generally not necessary to drill holes with convex cutting blades.

If desired, the invention can also be designed so that the cutting insert 5 has a single side 10, in which case the side 10 has a clearance angle which is sharper than usual. Here the clearance angle is preferably between 35° and 50°, preferably 40° should be selected.

Furthermore, a development of the invention is a drill with one or more cutting inserts or an auxiliary cutting insert and auxiliary cutting elements, the main cutting inserts and/or the auxiliary cutting elements having the above-mentioned features. Therefore, the invention also relates in particular to the protection of such carbide cutting elements, not limited to a certain geometry of the drill.

The invention is not restricted to the shown and described exemplary embodiment. On the contrary, it also includes all modifications that can be realized by those skilled in the art within the scope of the claims of the present invention. In particular, other combinations of the above-mentioned technical features can be selected.

1 rock drill

2 drill shank

3 drill bits

4 front end

5 cutting inserts

6 forward slope

7 cutting edge

8 Arrow/direction of rotation

9 Longitudinal axis of symmetry

10 side

11 side part

12 side parts

13 planes

14 Center plane

15 support body

16 Drilling direction

17 surface part

18 surface part

19 15 side walls

20 5 side walls

21 transition zone

22 chip flute

23 drilling points

24 chisel tip

25 side walls

26 side wall

27 The edge between 25 and 26

28 The edge between 11 and 12

α rake face angle (forward rake angle)

β roll angle (clearance angle)

Claims (27)

1. rock borer, have a drillstock (2) and a drill bit (3), this drill bit (3) points to direction of feed and has at least one cutting tip (5) on its front end, this cutting tip (5) has the cutting edge (7) at least one front end that is arranged on cutting tip (5), it is characterized in that: be provided with one and have the rake (6) of corresponding negative front rake angle (α) and have side (10) in the back of end cutting edge (7) with corresponding angle of heel (β), wherein, side (10) is divided at least two lateral parts (11,12), and a single rake (6) wherein is provided, and its front rake angle in abutting connection with cutting edge (7) (α) is greater than the angle of heel (β 1) of first lateral parts (11) of adjacency cutting edge (7).

2. rock borer as claimed in claim 1, it is characterized in that: one first lateral parts (11) has 1=20 °～40 ° of angle of heel β, and one second lateral parts (12) has 2=40 °～60 ° of angle of heel β, and front rake angle α and angle of heel β 1, β 2 define with respect to a plane perpendicular to drill axis (9) (13).

3. rock borer as claimed in claim 1 or 2, it is characterized in that: first lateral parts (11) that links to each other with end cutting edge or cutting edge (7) has a projected length S1 who is positioned at plane (13), second lateral parts (12) that links to each other then has a projected length S2, its summation is a length b, wherein S1=(0.4～0.7) * b.

4. rock borer as claimed in claim 1 or 2, it is characterized in that: the end cutting edge (7) of carbide cutting blade (5) departs from the central plane (14) of cutting tip (5), wherein, the projected length S3 of rake (6) be cutting tip (5) overall width B 1/3～1/6.

5. rock borer as claimed in claim 1 is characterized in that: rake (6) plane earth extends with constant front rake angle (α), perhaps rake (6) be designed to convex or spill.

6. rock borer as claimed in claim 1, it is characterized in that: cutting tip (5) embeds in the drill bit (3) like this, the feasible supporter (15 that is located at cutting tip (5) both sides, 15 ') has an exterior contour (19,19 '), this exterior contour (19,19 ') transits directly to tangentially or leads in the sidewall (20) of second lateral parts (12), rake (6) and cutting tip (5) at least one.

7. rock borer as claimed in claim 1, it is characterized in that: the supporter (15 that is located at cutting tip (5) both sides of drill bit (3), 15 ') have one at least two dimension, cylindrical radial or exterior contour (19 recessed arch or the plane, 19 '), it does not form the detention surface of end and leads on the sidewall (20) of carbide cutting blade (5).

8. rock borer as claimed in claim 7 is characterized in that: the exterior contour (19,19 ') of the supporter (15,15 ') in the drill bit (3) be designed to small part be convex.

9. rock borer as claimed in claim 1 is characterized in that: cutting tip (5) is gone up at the whole diameter D1 of drill bit (3) at least and is extended, and from its wide side, is designed to have the roof shape of one jiao of γ=130 °.

10. rock borer as claimed in claim 2 is characterized in that: angle of heel β 1=20～30 °, and 2=60 ° of angle of heel β.

11. rock borer as claimed in claim 4 is characterized in that: the projected length S3 of rake (6) be cutting tip (5) overall width B 1/5.

12. rock borer as claimed in claim 1 is characterized in that: described drill bit has a main cutting blade and a plurality of assisted machining parts.

13. rock borer, have a drillstock (2) and a drill bit (3), this drill bit (3) points to direction of feed and has at least one cutting tip (5) on its front end, this cutting tip (5) has the cutting edge (7) at least one front end that is arranged on cutting tip (5), it is characterized in that: be provided with one and have the rake (6) of corresponding negative front rake angle (α) and have side (10) in the back of end cutting edge (7) with corresponding angle of heel (β), wherein, cutting tip (5) has a single rake (6), and front rake angle (α) is between 60 ° to 80 °, wherein, cutting tip (5) embeds in the drill bit (3) like this, the feasible supporter (15 that is located at the drill bit (3) of cutting tip (5) both sides, 15 ') has an exterior contour (19,19 '), this exterior contour (19,19 ') leads on the sidewall (20) of cutting tip (5), and does not form the detention surface of end.

14. rock borer as claimed in claim 13 is characterized in that: rake (6) plane earth extends with constant front rake angle (α), perhaps rake (6) be designed to convex or spill.

15. rock borer as claimed in claim 13 is characterized in that: cutting tip (5) has one and has angle of heel β=35 ° to 50 ° single side (10) or a plurality of lateral parts (11,12).

16. rock borer as claimed in claim 13 is characterized in that: described exterior contour (19,19 ') transits directly to tangentially or leads in the sidewall (20) of second lateral parts (12), rake (6) and cutting tip (5) at least one.

17. rock borer as claimed in claim 13 is characterized in that: the supporter (15,15 ') that is located at cutting tip (5) both sides of drill bit (3) have one at least two dimension, cylindrical radial or exterior contour recessed arch or the plane (19,19 ').

18. rock borer as claimed in claim 17 is characterized in that: the exterior contour (19,19 ') of the supporter (15,15 ') in the drill bit (3) be designed to small part be convex.

19. rock borer as claimed in claim 13 is characterized in that: cutting tip (5) is gone up at the whole diameter D1 of drill bit (3) at least and is extended, and from its wide side, is designed to have the roof shape of one jiao of γ=130 °.

20. rock borer as claimed in claim 15 is characterized in that: front rake angle α=70 °, and angle of heel β=40 °.

21. rock borer as claimed in claim 13 is characterized in that: described drill bit has a main cutting blade and a plurality of assisted machining parts.

22. rock borer, have a drillstock (2) and a drill bit (3), this drill bit (3) points to direction of feed and has at least one cutting tip (5) on its front end, this cutting tip (5) has the cutting edge (7) at least one front end that is arranged on cutting tip (5), it is characterized in that: be provided with one and have the rake (6) of corresponding negative front rake angle (α) and have side (10) in the back of end cutting edge (7) with corresponding angle of heel (β), wherein, for reducing the length (l) of the chisel edge (24) in the plan view of instrument, the rake (6) of cutting tip (5) and/or the width of one second lateral parts (12) in the plan view of boring bar tool increase towards boring point (23) over there gradually.

23. rock borer as claimed in claim 22, it is characterized in that: cutting tip (5) embeds in the drill bit (3) like this, the feasible supporter (15 that is located at cutting tip (5) both sides, 15 ') has an exterior contour (19,19 '), this exterior contour (19,19 ') transits directly to tangentially or leads in the sidewall (20) of second lateral parts (12), rake (6) and cutting tip (5) at least one.

24. rock borer as claimed in claim 22, it is characterized in that: the supporter (15 that is located at cutting tip (5) both sides of drill bit (3), 15 ') have one at least two dimension, cylindrical radial or exterior contour (19 recessed arch or the plane, 19 '), it does not form the detention surface of end and leads on the sidewall (20) of carbide cutting blade (5).

25. rock borer as claimed in claim 24 is characterized in that: the exterior contour (19,19 ') of the supporter (15,15 ') in the drill bit (3) be designed to small part be convex.

26. rock borer as claimed in claim 22 is characterized in that: cutting tip (5) is gone up at the whole diameter D1 of drill bit (3) at least and is extended, and from its wide side, is designed to have the roof shape of one jiao of γ=130 °.

27. rock borer as claimed in claim 22 is characterized in that: described drill bit has a main cutting blade and a plurality of assisted machining parts.

28. rock borer, have a drillstock (2) and a drill bit (3), this drill bit (3) points to direction of feed and has at least one cutting tip (5) on its front end, this cutting tip (5) has the cutting edge (7) at least one front end that is arranged on cutting tip (5), it is characterized in that: be provided with one and have the rake (6) of corresponding negative front rake angle (α) and have side (10) in the back of end cutting edge (7) with corresponding angle of heel (β), wherein, side (10) has the camber profile of a protrusion, and wherein be provided with a single rake (6), its front rake angle (α) is greater than the angle of heel (β 1) of the camber profile of the protrusion of the side (10) of adjacency cutting edge (7).

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