JPS634567Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a cutting tool that is rotated relative to a workpiece and fed in one direction to cut the workpiece, and in particular, the present invention relates to a cutting tool that is rotated relative to the workpiece and fed in one direction to cut the workpiece. This invention relates to a cutting tool with an adjustable main cutting edge angle suitable for machining a surface in one step.

In cutting, there are cases where it is required to precisely machine two substantially perpendicularly adjacent surfaces of a workpiece so that the angle formed by the two surfaces is exactly a desired angle. For example, this is the case when machining the counterbore inner circumferential surface and bottom surface of a seat driving hole in a cylinder head, which requires a high degree of perpendicularity.

By the way, such machining can be done by changing the feeding direction of the cutting tool if the required angle between the two surfaces is a right angle and there is no restriction on the feeding direction of the cutting tool. Although it can be easily done in one process, when the required angle between the two surfaces is not a right angle, or when the feeding direction of the cutting tool is limited to one direction due to surrounding conditions, for example, the above-mentioned cylinder When the feeding direction of the cutting tool between the hole diameters is limited to the direction of the center line of the hole, as in the case of machining a sheet driving hole for the head, the feeding direction of the cutting tool should be changed as described above. In such cases, the two adjacent surfaces must be machined using separate cutting tools, or when machining is performed using one cutting tool, the normal Since it is difficult to accurately position the cutting edge with respect to the two surfaces to be machined with a throw-away tip, etc., a special blade is manufactured to obtain the desired angle, and using that special blade, or It was common practice to use a special holder for processing. However, it is not desirable in terms of processing efficiency to process the two surfaces using separate cutting tools, and it is not desirable in terms of equipment cost to prepare a dedicated blade or the like for such processing.

The present invention was developed against the background of the above-mentioned circumstances, and its purpose is to rotate the workpiece relative to the workpiece and feed the workpiece in one direction. It is a cutting tool that performs cutting, and the main cutting edge angle of the cutting tool with respect to the feed direction can be adjusted, and as mentioned above, the machining that requires precision in the angle formed by two adjacent surfaces can be performed using a normal throw-away method. 1 using a tip or blade
It is an object of the present invention to provide a cutting tool that enables highly accurate cutting processes.

In order to achieve this object, the cutting tool according to the present invention includes: (a) a circular arc cut formed in the nose portion in order to cut the workpiece surface along the feed direction of the workpiece; (b) A cutting tool such as a throw-away tip or a round cutting tool having a blade and a main cutting edge extending from the arcuate cutting edge in a direction substantially perpendicular to the feed direction; (c) a tool rest having an arc-shaped guided surface whose center coincides with the arc center of the arc-shaped cutting blade; and (c) a tool rest holder having an arc-shaped guide surface corresponding to the guided surface of the tool rest. (d) a clamp means for fixing the tool rest to the tool rest holder in a state in which the guided surface is in close contact with the guide surface; (e) the tool main body and the tool rest; When the clamping means is in an unclamped state, the screwing position with respect to the one is changed by being screwed into one of the two, and the other is engaged with the other, thereby changing the circle of the guide surface with respect to the tool body of the tool rest. and at least one adjusting screw for adjusting the relative position in the circumferential direction, so that the angle of the main cutting edge with respect to the feeding direction can be adjusted without changing the center position of the arcuate cutting edge.

According to the cutting tool having such a configuration, once the arcuate cutting edge of the cutting tool is positioned, the position does not change even if the angle of the main cutting edge with respect to the feeding direction is changed. Therefore, it is possible to first determine the position of the circular cutting edge and then adjust the angle of the main cutting edge with respect to the feed direction to the desired angle, making it possible to easily and accurately position both cutting edges. By positioning and feeding in one direction, both the work surface cut by the main cutting edge and the work surface cut by the arc cutting blade can be cut with high precision, and the angle between these two surfaces can be adjusted to the desired angle. It can be processed accurately.

In other words, according to the cutting tool of the present invention, by the simple positioning operation as described above, two adjacent surfaces can be simultaneously moved by feeding in one direction, and the angle formed by those two surfaces can be accurately set to the desired angle. This makes it possible to machine angles with high precision, and by making it possible to machine two surfaces like this with only one direction of feed, it is possible to improve machining efficiency and reduce machining costs. It is possible. In addition, as mentioned above, positioning operations can be performed easily and accurately, so even ordinary inexpensive throw-away tips or round bits can be used, eliminating the need to prepare a special blade. This makes it possible to reduce equipment costs for cutting tools.

Hereinafter, one embodiment of the present invention will be described in detail based on the drawings. In this example, the present invention is applied to a cutting tool for machining the counterbore inner circumferential surface and bottom surface of a seat driving hole in a cylinder head, which requires highly accurate perpendicularity to the two work surfaces. However, it goes without saying that the present invention may be applied to cutting tools for machining other workpieces.

First, Fig. 1 shows a front view of the cutting tool of this embodiment as seen from a direction perpendicular to the feeding direction, and Fig. 2 shows a side view (as viewed from the arrow in Fig. 1) as seen from a direction opposite to the feeding direction. ) are shown respectively.

In these figures, 12, 14 and 16
are a throw-away tip (hereinafter simply referred to as a tip), a tip stand, and a tool body, and the cutting tool of this embodiment has a structure in which the tool body 16 fixedly supports the tip 12 via the tip stand 14. has been done.

The chip 12 is a normal throw-away chip with a triangular shape, and one of the three straight edges has a main cutting edge, as shown enlarged by the two-dot chain line in FIGS. 3 and 4. An arcuate cutting edge 22 functioning as a main cutting edge 18 and continuous with the main cutting edge 18 defines a nose portion.

Further, as shown in FIGS. 3 and 4, the tip stand 14 is a substantially fan-shaped member with an arcuate surface 24, and a tip seat 26 corresponding to the shape of the tip 12 is provided at the apex portion of the tip stand 14. is formed. Then, the chip 12 is accommodated in the chip seat 26,
As shown in FIGS. 1 and 2, it is fixed by a clamp member 28 and a bolt 29, and by being accommodated and fixed in the chip seat 26 in this way. Thus, the tip 12 is fixed in a predetermined position relative to the tip stand 14. That is, in this example, as shown in FIGS. 1 and 2,
In a state where the tip stand 14 is attached to the tool body 16, the cylinder head 2 as a workpiece is
The inner peripheral surface of the hole (workpiece surface) along the cutting tool feed direction (horizontal direction in Fig. 1) of the counterbore hole, which is the sheet driving hole in No. 7, and the hole bottom surface (workpiece surface) perpendicular to the feed direction. In order to perform cutting in one step by feeding in one direction, the arcuate cutting edge 22 of the chip 12 is oriented laterally from the tool body 16 in the feeding direction, and the main cutting edge 18 is approximately perpendicular to the feeding direction. They are fixed so as to slightly protrude forward in the feeding direction, and when the tip 12 is fixed in this way, the center of the arcuate cutting edge 22 of the tip 12 is aligned with the center of the arcuate surface 24 of the tip holder 14. It is made to be.

Further, as shown in FIGS. 5 and 6, the tool body 16 includes an attached portion 32 that is attached to the tool rest 30 (FIG. 1), and a tip rest holding portion 3.
4 and a tip mount mounting portion 36 formed with the tip holder 4. The tip holder 34 is a fan-shaped notch, and is defined by an arcuate surface 38 having a shape corresponding to the arcuate surface 24 of the tip holder 14 . As shown in FIG. 1 and FIG.
The chip holder 8 is housed in the chip holder holder 34 in close contact with the chip holder 8, and in such a housed state is fixed by a clamp member 40 and a bolt 41 as a clamping means. That is, in this embodiment, by housing and fixing the tip stand 14 in the tip stand holder 34 as described above, the tip stand 14 can be fixed regardless of the angle at which the tip stand 14 is attached to the tip stand holder 34. The center position of the circular arc surface 24 of the chip 12, that is, the center position of the circular arc cutting edge 22 of the chip 12, is uniquely determined with respect to the tool body 16.
The cutting edge position on the side of the feeding direction of the circular cutting blade 22 of No. 2 is
Even if the angle at which the tip holder 14 is attached to the tip holder 34 changes, it does not change relative to the tool body 16. In other words, once the tool body 16 is positioned with respect to the cylinder head 27 as the workpiece, even if the mounting angle of the tip holder 14 to the tip holder 34 is changed, the direction perpendicular to the feeding direction of the tip 12 will be fixed. The position of the cutting edge does not change relative to the workpiece.

On the other hand, as shown in FIGS. 1 and 2, adjustment screws 42 are provided in the vicinity of the tip holder attachment part 36 of the tool body 16, where the end of the arcuate surface 38 of the tip holder holder 34 faces. They are screwed together. These adjustment screws 42 are configured so that their heads can engage with portions of the tip table 14 housed in the tip table holder 34 adjacent to both ends of the circular arc surface 24 from opposite sides, and are used as clamp members. 40 is in an unclamped state in which the tip stand 14 is not fixed, by changing the screwing position (threading depth) with respect to the tool body 16, the arcuate surfaces 24, 38 of the tip stand 14 relative to the tip stand holding part 34 can be adjusted. It is possible to adjust the relative position in the circumferential direction, that is, the angle of the main cutting edge 18 of the chip 12 with respect to the tool body 16, and thus the angle with respect to the feeding direction. Note that by adjusting the main cutting edge angle by changing the screwing position of the adjusting screw 42 in this way, the adjustment can be performed with high precision.

Further, as shown in FIGS. 5 and 6, a stepped hole 44 is formed in the chip holder mounting portion 36 by opening into the circular arc surface 38 of the chip holder holder 34, and as shown in FIG. As shown in FIG. A compression coil spring 48 is provided that biases the surface 38 in a direction in which the surface 38 comes into close contact with the arcuate surface 24 of the chip base 14 when adjusting the main cutting edge angle of the chip 12 using the adjustment screw 42. is prevented from leaving the arcuate surface 38 of the tip holder 34. Therefore, after the main cutting edge angle is adjusted while the arcuate surface 24 of the chip holder 14 is guided by the arcuate surface 38 of the chip holder 34, the arcuate surface 24 is brought into close contact with the arcuate surface 38. In this state, the tip stand 14 is fixed by the clamp member 40. In this embodiment, the arcuate surfaces 38 and 2
4 are used as a guide surface and a guided surface, respectively, and if a biasing means is provided as described above to keep the guided surface of the chip holder 14 in close contact with the guide surface of the chip holder holder 34 at all times. When adjusting the main cutting edge angle by changing the screwing position of the adjustment screw 42, the center position of the arcuate cutting edge 22 does not shift with respect to the tool body 16.

That is, according to this embodiment, the tip 12 can be moved without changing the relative position of the tool body 16 with respect to the workpiece (cylinder head 27).
Without changing the center position of the arcuate cutting blade 22, and by extension, the position of the cutting edge of the arcuate cutting blade 22 with respect to the workpiece surface (inner peripheral surface of the counterbore hole) along the feed direction,
The relative angle of the main cutting edge 18 to the workpiece surface (bottom of the counterbore hole) can be adjusted with high precision, and the main cutting edge 18 and the circular cutting edge 22 can be positioned independently, so the throw-away tip 12 can be easily positioned, and two mutually perpendicular work surfaces can be machined at once by only feeding in one direction.

Incidentally, the above-mentioned cutting tool has a tool rest 3 as shown by the two-dot chain line in FIGS. 1 and 2.
The tool rest 30 is preferably one that can finely adjust the position of the cutting edge in a direction perpendicular to the feeding direction of the cutting tool provided with the eccentric sleeve 31. If the cutting edge position in the direction perpendicular to the feeding direction can be finely adjusted, use the circular cutting blade 2.
This is because the cutting edge position of No. 2 can be positioned with extremely high precision, so that the advantages of the cutting tool of this embodiment can be more effectively exhibited.

Although one embodiment of the present invention has been described above, this is literally an illustration, and the present invention should not be interpreted as being limited to the above embodiment.

For example, in the embodiment described above, a normal triangular throw-away tip 12 is used as the cutting tool, which is connected to the clamp member 28 and the bolt 2.
9, the throw-away tip is fixed to the tip holder 14 by means of bolts 9, but throwaway tips of other shapes such as rhombus may also be used, and they can also be attached to the tip holder by directly tightening bolts. It's good to wear. Further, a cutting tool such as a round cutting tool, which itself has a shank portion, may be used by being fixed to a cutting tool holder similar to the tip holder 14. In short, a cutting tool having a circular cutting edge for cutting the surface of the workpiece along the feeding direction and a main cutting edge extending from the circular cutting edge in a direction substantially perpendicular to the feeding direction is a chip head, It is sufficient if it is fixedly supported by a cutting tool stand such as a cutting tool holding stand.

Furthermore, in the embodiment described above, the arcuate surface 38 as a guide surface of the tip holder 34 was explained as having a shape that simply corresponds to the arcuate surface 24 as a guided surface, but as is clear from FIG. However, the guided surface does not necessarily have to be a circular arc surface over the entire surface like the guided surface of the chip holder 14, but the guided surface must be within the range where the main cutting edge angle of the chip is adjusted and when adjusting the main cutting edge angle. As long as the shape allows the cutting edge to be guided in an arc without changing the center position of the cutting edge with respect to the tool body, it may have a shape that partially contacts the guided surface. Note that this is also true even if the positions of the guided surface on the chip stand side and the guide surface on the chip stand holding part side are changed.

Further, in the above embodiment, the main cutting edge angle of the tip 12 is adjusted by the two screws screwed into the tool body 16.
This could be done by engaging the heads of two adjustment screws 42 with the tip base 14, but
Only one of the adjusting screws 42 may be provided, and the main cutting edge angle can be adjusted by engaging the head of the adjusting screw screwed into the chip holder with the tool body. It's okay to get used to it.

Further, in the embodiment described above, a stepped hole 44 is formed in the tip holder mounting portion 36 of the tool body 16, and a bolt 46 and a compression coil spring 48 are provided in the stepped hole 44, thereby forming a biasing means. When adjusting the main cutting edge 18, the guided surface (arc surface 24) of the chip holder 14 is always urged in a direction in which it comes into close contact with the guide surface (arc surface 38) of the chip holder mounting portion 36. However, it is not always necessary to provide such a biasing means, and when adjusting the main cutting edge angle, the adjuster can directly push the guided surface of the chip holder onto the chip holder by hand or with an appropriate tool. Alternatively, the guide surface may be used to guide the user.

Although not listed in detail, it goes without saying that the present invention can be implemented with various modifications and improvements without departing from the spirit thereof.

[Brief explanation of the drawing]

FIG. 1 is a front view showing an embodiment of the present invention, FIG. 2 is a view taken in the direction of the arrow in FIG. 4 is a left side view of FIG. 3, FIG. 5 is a front view showing the tool body of the cutting tool of FIG. 1, and FIG. 6 is a left side view of FIG. 5. 12: Throwaway tip (cutting tool), 14:
Chip stand (cutting tool holding stand), 16: Tool body, 1
8: Main cutting edge, 22: Arc cutting edge, 24: Arc surface (guided surface), 27: Cylinder head (workpiece), 3
4: Chip stand holding part (tool stand holding part), 38: Arc surface (guide surface), 40: Clamp member (clamping means), 41: Bolt (clamping means).

Claims (1)

[Claims for Utility Model Registration] A cutting tool that is rotated relative to a workpiece and is fed in one direction to cut the workpiece, the tool comprising: A cutting tool having an arcuate cutting edge formed in a nose portion and a main cutting edge extending from the arcuate cutting edge in a direction substantially perpendicular to the feeding direction; a tool rest that is fixedly supported and has an arcuate guided surface whose center coincides with the arc center of the arcuate cutting edge of the tool; and an arcuate guide surface that corresponds to the guided surface of the tool rest. a tool body including a tool rest holding part having a tool rest; a clamp means for fixing the tool rest to the tool rest holding part in a state in which the guided surface is in close contact with the guide surface; the tool main body and the tool rest; The guide surface of the tool rest relative to the tool body is screwed into one of the two and engaged with the other, and the screwing position relative to the one is changed when the clamp means is in an unclamped state. At least one adjustment screw for adjusting the relative position in the circumferential direction, and the angle of the main cutting edge with respect to the feeding direction can be adjusted without changing the center position of the arcuate cutting edge. A cutting tool with an adjustable main cutting edge angle.