JP2002059314A - Machining tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a machining tool capable of improving machining efficiency and quality, and extending life of the tool. SOLUTION: A reamer portion 30 is provided at a tip end portion of a machining tool 10 shaped in a rod. A grinding tool portion 20 is provided in a base end portion side from the reamer portion. The grinding tool portion is made by adhering strip-shaped grinding tools 22 at even angle intervals and in axially parallel with each other on an outer peripheral surface of a body 16. The grinding tools are electrolytic deposition grinding tools electrodepositing abrasive grains on an outer peripheral surface of a main body. Finish machining and grinding machining can be conducted in one process, so that machining efficiency is improved. The grinding tool portion is guided by the reamer portion, thereby improving concentricity between the grinding tool portion and a machined hole, so that machining accuracy is improved and life of the tool is extended. A groove 34 of the reamer portion is made to be deeper than a groove 24 of the grinding tool portion, and a front end edge in a rotating direction of the grinding tool 22 is shifted forward in the rotating direction than a cutting edge of a tip 32, thereby preventing the entry of chips of the reamer portion into the grinding tool portion.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a machining tool for machining a metal product, and more particularly to a tool capable of machining an inner peripheral surface of a hole with high precision.

[0002]

2. Description of the Related Art Conventionally, when it is necessary to machine the inner peripheral surface of a hole particularly well, that is, it is necessary to perform machining in which at least one of dimensional accuracy, surface roughness, roundness and straightness is particularly good. In some cases, grinding with a grindstone has been performed after cutting with a reamer (referred to as reamer processing). However, when performing the grinding process, it is necessary to insert the shaft-shaped grindstone in a state accurately positioned with respect to the hole to be machined, if the relative positional accuracy between the grindstone and the hole to be machined is poor , Cannot perform high-precision drilling.
Therefore, a guide part called a pilot is provided at the tip of the shaft-shaped grindstone. First, the guide part is inserted into the hole to be machined, and the relative position between the hole to be machined and the grindstone is adjusted. Processing had to be started.

[0003]

However, in order to insert the pilot into the hole to be machined, a gap is required between the outer peripheral surface of the pilot and the inner surface of the hole to be machined. However, it is inevitable that the relative position between the grindstone and the hole to be machined is shifted (referred to as misalignment) only by this gap, and this is a serious factor that hinders the improvement of the machining state of the inner peripheral surface of the hole.

SUMMARY OF THE INVENTION [0004] The present invention has been made in view of the above circumstances, and has as an object to obtain a machining tool capable of processing the inner peripheral surface of a hole better than before.
The following processing tools are obtained. As in the case of the claims, each aspect is divided into sections, each section is numbered, and if necessary, the other sections are cited in a form in which the numbers are cited. This is for the purpose of facilitating the understanding of the present invention and should not be construed as limiting the technical features and combinations thereof described in the present specification to those described in the following sections. .
Further, when a plurality of items are described in one section, the plurality of items need not always be adopted together. It is also possible to select and adopt only some of the items.

(1) A processing tool which is generally axially shaped, has a reamer portion at the distal end side in the axial direction, and has a grindstone portion at the base end side thereof, and the outer diameter of the grindstone portion is slightly larger than the outer diameter of the reamer portion. . In this manner, if the reamer is provided on the distal end side of the generally axial processing tool, and the grindstone portion is provided on the base end side, that is, on the end side held by the tool holder such as the chuck, the workpiece can be processed. When machining the inner peripheral surface of the hole, first, the reaming portion is inserted into the hole to be machined, reaming is performed, and the machining tool is inserted deeper into the hole to be machined, whereby grinding can be performed. Unlike the pilot part, the reamer has the ability to cut the inner peripheral surface of the hole to be processed, so that a reamer having an outer diameter larger than the inner diameter of the hole to be processed can be inserted into the hole to be processed. . And since the reamer part fits into the hole to be machined by itself, the outer diameter of the reamer part is almost equal to the inner diameter of the hole to be machined. Moreover,
Even if there is some misalignment between the two before the reamer is inserted into the hole to be machined, the misalignment is reduced by cutting the hole to be machined. Therefore, the reamer part fits into the hole to be machined with almost no gap and performs the function of a pilot, so that the grindstone is inserted into the hole to be machined in a state where it is accurately positioned concentrically with the hole to be machined, and the grinding process is performed. , The extremely good processing of the hole to be processed can be performed, and the life of the grindstone is prolonged. All metal materials such as steel, cast iron, and non-ferrous metals can be machined, and the inner peripheral surface of the hole to be machined can be machined much better than in the past. In addition, since reaming and grinding can be performed continuously, the relative positioning between the hole to be machined and the tool only needs to be performed once. There is no need to perform this, and an effect of improving the processing efficiency can be obtained. (2) The reamer has at least one reamer groove extending in a direction including at least an axial component. (1)
The processing tool described in the item. (3) The groove of the reamer is terminated in the reamer.
(2) The processing tool according to item (claim 1). The workpiece is cut by the cutting edge formed on the edge of the side surface on the rear side in the rotation direction of the reamer groove of the reamer. Chips generated at that time may reach the grindstone portion via the reamer groove, and may be caught between the ground surface of the grindstone portion and the ground surface of the workpiece to cause flaws on the ground surface. This phenomenon occurs at the beginning of the use of a new machining tool, or occurs after machining about 1000 workpieces. On the other hand, if the reamer groove is terminated inside the reamer, that is, at the end of the reamer side of the grindstone or at a position closer to the reamer, chips will reach the grindstone and flaws will occur on the surface to be ground. It is possible to reduce the probability of causing the error. This structure is referred to as a “groove reamer end structure”. From the viewpoint of preventing the generation of flaws on the surface to be ground, when terminating the reamer groove,
It is desirable to sharply reduce the cross-sectional area at the end of the reamer groove, but it is easier to machine the cross-sectional area gradually. For example, the reamer groove can be formed by cutting with an end mill. In this case, the reamer groove becomes a V-shaped groove, and one side surface of the V-shaped groove is flat to the end, and the other side surface is a curved surface (often a cylindrical surface) at the end. It is often the case that the former is on the rake face side of the reamer part, so that the effect of preventing generation of flaws on the surface to be ground is greater. (4) The working tool according to the above mode (2) or (3), wherein the grindstone portion has at least one grindstone groove extending in a direction including at least an axial component. The grindstone portion may have a continuous grinding surface over the entire circumference, but it is often the case that at least one grindstone portion groove can be satisfactorily ground. It is more desirable to provide a plurality of grindstone grooves and divide the grinding surface into a plurality in the circumferential direction. (5) The end of the rear edge in the rotation direction of the grindstone groove on the reamer side is offset forward in the rotation direction from the end of the rear edge in the rotation direction of the reamer groove in the rotation direction. (4) The processing tool according to item (claim 2). The phenomenon that the chips generated in the reamer generate flaws in the surface to be ground is referred to as the “rear edge offset structure” according to this section.
Can also lower the probability. Chips moving toward the grindstone portion along the rotation direction rear side surface of the reamer portion groove are blocked by the end surface of the portion of the grindstone portion where the grindstone portion groove is not formed, and it is difficult to move to the grindstone portion side. It is speculated that this is one factor. (6) The processing tool according to (4) or (5), wherein the grindstone groove is communicated with the reamer groove and is made shallower than the reamer groove. When both the reamer groove and the grindstone groove are formed so as to communicate with each other, it is effective to make the latter shallower than the former in order to prevent generation of flaws on the surface to be ground. This structure is referred to as a “groove depth change structure”. It is more effective to make the grindstone groove shallower than the reamer groove in a stepped manner. This can also be considered as one mode of the “structure in the groove reamer end”.
When the depth of the groove becomes shallower in a stepped manner, it can be considered that the reamer part groove is terminated. Although the above "groove depth change structure" is effective even when used alone,
It is more effective if used in combination with the "rear edge offset structure". (7) The processing apparatus according to any one of (4) to (6), wherein the reamer portion and the grindstone portion each include a plurality of the reamer groove and the grindstone groove. Item 4). As the reamer part, a so-called single-blade reamer having a reamer part groove and a cutting edge at only one place on the outer peripheral surface can also be adopted, but a plurality, preferably four or more, preferably provided at four or more places, Equal angular intervals are possible, but unequal angular intervals are preferred. (8) Any one of (4) to (7), including a coolant passage extending substantially in the axial direction therein, and an ejection hole extending from the coolant passage and opening at least on an inner surface of the grindstone groove. The processing tool according to claim (claim 5). The ejection holes are preferably provided at a plurality of positions separated in at least one of the circumferential direction and the axial direction, and particularly preferably provided at a plurality of positions in at least the circumferential direction. Most desirably, at least one jet hole is provided in each grindstone groove of the grindstone portion. The “grinding portion groove ejection hole forming structure” in which at least one ejection hole is provided in each of the grinding stone portion grooves is referred to as the “groove depth changing structure”.
It is more effective if employed in combination with at least one of the following. By doing so, the movement of the chips from the reamer groove to the grindstone groove can be more favorably prevented by the coolant jet flowing from the grindstone groove to the reamer groove. In addition, between each cutting edge of the reamer part (in the state opened in the inner surface of the reamer part groove)
An ejection hole may be provided. In many cases, it is preferable to provide ejection holes in both the reamer portion and the grindstone portion. (9) The grindstone pieces are fixed at one or more positions circumferentially separated on the outer peripheral surface of the shaft portion of the grindstone portion in a state where the grindstone pieces protrude radially outward from the outer peripheral surface. Not
(8) The machining tool according to any one of the above items. The grindstone portion land is formed by fixing a strip-like grindstone piece to the outer peripheral surface of the shaft portion of the metal tool main body or the bottom surface of the concave portion formed in the outer peripheral surface. The grindstone piece may be attached to the tool main body so as to be position-adjustable for the purpose of adjusting the processing diameter or the like. The whetstone piece may be composed entirely of a whetstone, or may be a wrist piece having a whetstone layer fixed to at least one surface of a metal piece. The grindstone layer may be formed by electrodeposition. The fixing of the grindstone piece to the outer peripheral surface of the shaft portion is, for example,
The fixing can be performed by fixing (brazing, soldering, bonding, or the like) the shaft portion to the outer peripheral surface itself, or by fitting into the concave portion formed on the outer peripheral surface and fixing the concave portion to the inner surface. (10) The processing tool according to the above mode (9), wherein the grindstone piece extends in parallel to the axial direction. (11) The processing tool according to the above mode (9) or (10), wherein the whetstone piece extends in a direction having components of the axial direction and the circumferential direction and is twisted. (12) The processing tool according to any one of the above items (9) to (11), wherein a plurality of the grinding stone pieces are provided at a distance from each other in a circumferential direction. The grindstone pieces may be provided at equal angular intervals or at unequal angular intervals. (13) Items (9) to (4) wherein four or more pieces of the grinding stone are provided.
The processing tool according to any one of the above items (12). It is also possible to provide two grinding stone pieces at positions separated in the diameter direction,
Preferably, three or more are provided, and more preferably, four or more are provided. (14) Any one of the above items (1) to (8), wherein a land is formed integrally with the shaft portion of the whetstone portion, and abrasive grains are electrodeposited on the outer peripheral surface of the land to form an electrodeposited whetstone. The processing tool according to any one of the above. The electrodeposited whetstone is one in which diamond or CBN abrasive grains are fixed to the surface of a steel or carbide main body by electrodeposition. When there are a plurality of electrodeposited whetstones, for example, a plurality of grooves extending in the axial direction may be formed in the shaft portion, and abrasive grains may be electrodeposited on the outer peripheral portion to form a plurality of electrodeposited whetstones. At this time, the grooves may be masked to prevent electrodeposition of the abrasive grains, or the abrasive grains may be electrodeposited on both the groove and the outer peripheral surface. The features described in the above items (10) to (13) can be applied to the working tool described in this item. In that case, "grinding stone pieces" should be read as "electroplated grinding stones". (15) The cutting edge of the reamer section is formed by brazing a cutting tip to a front end in the rotation direction of a side wall on a rear side in the rotation direction of the groove of the reamer section. The processing tool according to any one of the above. The cutting tip is made of, for example, cemented carbide, ceramic, cermet or CBN,
It is formed of an ultra-high pressure sintered body such as diamond. (16) The working tool according to any one of (1) to (14), wherein the entire reamer portion is made of a superhard material and is fixed to a tip of a shaft-shaped tool body. (17) The working tool according to (16), wherein the entire reamer portion is fixed to the tool body by brazing. (18) The processing tool according to (16), wherein the entire reamer portion is detachably fixed to the tool body. (19) The machining tool according to any one of the above items (1) to (18), comprising a drill portion on a tip side from the reamer portion. According to the processing tool having the drill part, the reamer part and the grindstone part integrally, not only the relative positioning precision of the grindstone part with respect to the hole to be machined but also the relative positioning precision of the reamer part with respect to the hole to be machined can be improved. Further, the processing efficiency can be further improved.

[0006]

1 to 4 show a working tool 10 according to an embodiment of the present invention. This machining tool 10
Performs a finishing process including a cutting process and a grinding process on a prepared hole formed in advance in one step.

The working tool 10 has a stepped cylindrical body 12. The rear end of the main body 12 is a shank 14 having a relatively large diameter, and a relatively small diameter body 16 extends coaxially from the shank 14. At the center of the main body 12, a coolant hole 18 is formed in the axial direction. The processing tool 10 is held by a holder (not shown) on the shank 14, and is attached to a spindle (not shown) via the holder. The spindle is rotatably held by a headstock (not shown), and the headstock is moved in the axial direction of the spindle by a feeder (not shown). The configurations such as the holder and the main shaft are generally known and are not indispensable for understanding the present invention.

The body 16 has a relatively long cylindrical shape, and a grindstone portion 20 as a grinding portion is provided near the tip of the body. The grindstone portion 20 has six grindstones 22. The grindstones 22 are formed in a strip shape along the axial direction, and are provided on the outer peripheral surface of the body 16 at equal angular intervals. Whetstone 22
Is an electrodeposited whetstone formed by electrodepositing abrasive grains on the outer peripheral surface of the body 16. The abrasive grains are, for example, diamond or CBN (cubic boron nitride), and are fixed by electrolytic plating using nickel or the like.

An axially extending groove 24 is formed between adjacent grinding wheels 22. The grooves 24 are longer than the grindstone 22 and are formed to protrude from both ends in the longitudinal direction of the grindstone 22. Each grindstone 22 forms a land (grindstone part land) of the grindstone part 20, and each groove 24 can be considered to be formed as a grindstone part groove extending along the land in the rotation direction of the land. . The above-described coolant hole 18 is a deep hole extending from the rear end surface of the shank 14 to the middle of the grindstone portion 20. A communication path 26 for communicating the coolant hole 18 with the groove 24 is formed (see FIG. 2). The communication path 26 has two grooves for each groove 24.
The books are formed at a distance from each other in the axial direction and open at the groove bottom. One of the coolant outlets 28, which is a groove-side opening, is formed behind the grindstone portion 20, and the other is formed in the latter half of the grindstone portion 20. The coolant hole 18 is provided in a reamer 3 to be described later.
The coolant outlet 28, which is a groove-side opening of the communication passage 26, is formed in the rear half of the reamer 30. Coolant liquid is in coolant hole 1
The coolant is discharged from the coolant outlet 28 through the passage 8 and the communication passage 26. Thereby, the coolant liquid is favorably supplied to the grindstone portion 20 and the reamer portion 30 during the grinding process.

[0010] A reamer 30 is provided at the tip of the body 16 as a cutting portion. The reamer unit 30 performs cutting of a pilot hole prior to the grinding wheel unit 20 described above. The reamer 30 has six strip-shaped chips 32, which are fixed to the outer periphery of the body 16 by brazing. Specifically, as shown in FIG. 3, six grooves 34 extending parallel to the axial direction are formed at equal angular intervals on the outer peripheral surface of the body 16, and the rear side wall of the groove 34 in the rotation direction is The tip 32 is fixed to the front end in the rotation direction. These side walls and the chip 32 constitute a land of the reamer part 30 (land of the reamer part), and the groove 34
However, it can be considered that the reamer groove extends along each land in front of the lands in the rotation direction. Each groove 34 is formed deeper than the groove 24 in the above-described grindstone portion 20. The groove 34 is rounded up in the latter half portion near the grindstone portion 20, the depth is gradually reduced, and is terminated immediately before the grindstone portion 20. The diameter of the reamer 30 including the tip 32 is slightly smaller than the diameter of the grindstone 20. The groove 34
It may be formed longer than the tip 32, and may be rounded up anywhere between the tip 32 and the grindstone 22. Further, the rear half of the groove 34 may be cut up gently as shown in FIGS. 1 and 4, or may be cut up more rapidly. For example, when the radius of curvature of the rounded-up portion is groove 3
4 or more or 3 or more times the depth of 4,
It may be 1.5 times or less. The former is desirable for processing, and the latter is desirable for avoiding intrusion of chips between the grindstone portion 20 and the surface to be ground.

This will be described in more detail. As shown in FIG. 4, in the present working tool 10, the phase of the tip 32 of the reamer 30 and the phase of the grindstone 22 of the grindstone section 20 are different. (Note that in FIG. 1, the chip 32 is shown for ease of illustration.
And a part of the grindstone 22 are omitted, and the phase shift between the reamer 30 and the grindstone 20 is ignored. Specifically, the front end in the rotational direction of the grindstone 22 corresponding to the cutting edge of each tip 32 is located forward in the rotational direction. In the present embodiment, the size of the deviation is about 2 times the width of the grindstone 22.
It is one in one. The relative phase between the tip 32 and the grindstone 22 is such that the phase of the cutting edge of the tip 32 is the phase in which the grindstone 22 is present, and excluding the vicinity of the front end and the vicinity of the rear end of the grindstone 22 in the rotation direction. However, it is desirable that the magnitude of the deviation between the cutting edge of the tip 32 and the front end in the rotation direction of the grindstone 22 be within a range of not less than ４ of the width of the grindstone 22 and not more than about ４.

As described above, in the present working tool 10,
Since the grindstone 22 of the grindstone portion 20 is provided so as to be displaced forward in the rotation direction with respect to the chip 32 of the reamer portion 30, it is possible to satisfactorily prevent chips generated in the reamer portion 30 from entering the grindstone portion 20. it can. Chips generated in the reamer portion 30 often move to the grindstone portion 20 side along the surface of the chip 32 on the groove 34 side, and this movement is caused by the cut-up portion at the rear end of the groove 34 and the grindstone. 22 is prevented by the front end face in the axial direction, and the intrusion into the grindstone portion 20 is effectively prevented. As shown in FIG. 4, there is a portion where the groove 34 of the reamer 30 and the groove 24 of the grindstone 20 overlap, but the groove 24 of the grindstone 20 is shallower than the groove 34 of the reamer 30. Since the groove is formed and the boundary between the groove 34 and the groove 24 is stepped, the movement of the chip toward the grindstone portion 20 is also prevented at this portion.

The coolant outlet 2 is provided on the inner surface of the groove 24.
8 is formed, from which coolant is blown into the groove 24. Moreover, since the communication passage 26 is inclined in a direction from the grindstone portion 20 side to the reamer portion 30 side as it goes radially outward, the reamer portion 3
A coolant flow toward the zero side is generated, and this flow also hinders the movement of the chips to the grindstone unit 20 side. In addition, as described above, the groove 24 of the grindstone portion 20 is
Is formed shallower than the groove 34, and the cross-sectional area of the groove 24 is smaller than the cross-sectional area of the groove 34. Therefore, the coolant flowing in the groove 24 is ejected to the groove 34, and the chip Movement is more effectively hindered.

Since the coolant injection hole 28 is formed on the inner surface of the groove 34 in the same manner as the coolant injection hole 28 of the groove 24, the coolant injected from the coolant injection hole 28 also It plays a role of flushing chips generated in the portion to the tip side of the processing tool 10, which also hinders the movement of chips toward the grindstone portion 20.

According to the present working tool 10, since the grindstone portion 20 is guided by the reamer portion 30, unlike the case where the grindstone portion is guided by the pilot portion, for example, the reamer portion 30 fits into the hole to be machined. Therefore, the outer diameter of the reamer portion 30 as the guide portion is substantially equal to the inner diameter of the hole to be processed, and the concentricity between the grindstone portion 20 and the hole to be processed increases.

An experiment was conducted to compare the case where the inner peripheral surface of the through hole was finished with the present processing tool 10 and the case where the same finishing was performed using a conventional reamer for finishing. . In this experiment, a single-blade reamer was used as a conventional reamer. The single-blade reamer is substantially the same as that described in detail in Japanese Patent Application No. 10-350320 filed by the present applicant, and will be described briefly.

FIGS. 5 and 6 show a conventional single-blade reamer 5.
Indicates 0. This reamer 50 is formed in a stepped cylindrical shape,
The body 52 on the tip side and a shank 5 smaller in diameter than the body 52
4 is provided. The body 52 and the shank 5
A coolant hole 55 extending in the axial direction is formed at the center of 4. As shown in FIG. 6, a main groove 56 and a sub-groove 58 extending in the axial direction are formed adjacent to each other on the outer periphery of the body 52, and open to the main groove 56 and the sub-groove 58 and communicate with the coolant hole 55. Passages 60 and 62 are formed. A chip 66 having CBN abrasive grains fixed to the surface thereof is fixed to the side surface 64 of the main groove 56 by brazing. Further, a notch 68 extending in the axial direction at a phase substantially opposite to that of the chip 66 is formed on the outer periphery of the body 52, and a communication passage 70 opened in the notch 68 and communicating with the coolant hole 55.
Are formed. Portions of the body 52 other than the main groove 56, the sub-groove 58, and the notch 68 serve as guides for guiding the reamer 50.

FIGS. 7 to 10 show changes in the processing diameter, surface roughness, roundness, and straightness when a large number of holes are processed using the present processing tool 10 and the conventional single-blade reamer 50. Is shown. In each figure, the circles filled in black indicate the results of processing by the present processing tool 10, and the white circles indicate the results.
The result of processing by the conventional single-blade reamer 50 is shown. The values in the graph show the results obtained by machining a plurality of holes per one in a casting block as a workpiece and measuring each of the holes to be processed. The length of the bar is the length of the workpiece in one casting block. The variation of holes is shown. In addition, the processing diameter, for the through-hole extending in the vertical direction, measure the diameter in the front-rear direction and the diameter in the left-right direction near the opening end on both sides,
The roundness measures the roundness near the open ends on both sides,
Straightness is a value based on the result of measuring the straightness of each line of intersection between two surfaces that are orthogonal to each other and whose intersection line coincides with the center line of the hole to be machined, and the inner peripheral surface of the hole to be machined. .

As is clear from the results of the comparative experiment, in the machining with the single-blade reamer 50, the diameter of the 25th machine changes so as to decrease the average diameter by 7 μm due to wear of the cutting blade. The variation of the processing diameter is about 8
μm. On the other hand, according to the working tool 10 of the present embodiment, there is almost no change in the diameter, and the variation of the working holes with respect to one workpiece does not become so large. Furthermore, although there is almost no difference in the roundness from the single-blade reamer 50, the surface roughness and the straightness are
It can be said that the present working tool 10 is more stable at a higher level.

Further, in the conventional machining tool, as described above, the chips generated in the reamer portion enter the grindstone portion and are sandwiched between the grinding surface of the grindstone portion and the surface of the workpiece to be ground. The surface may be flawed, and the phenomenon occurs at the beginning of use of a new machining tool, or occurs after machining a large number of approximately 1000 workpieces, and the quality of the workpiece is not stable. Was. On the other hand, this processing tool 10
According to the method, the probability that the above phenomenon occurs is reduced, and at least a fixed number (for example, about 1000) of workpieces can be stably processed.

As is clear from the above description, the present working tool 10 is different from the conventional finishing reamer 50 in that
The quality of drilling can be improved and the cost can be reduced. Furthermore, since the cutting and the grinding can be performed in one step, the processing efficiency can be improved.

In the present working tool 10, the coolant hole 18 is formed as a bottomed hole to prevent the coolant from flowing out from the tip of the body 16.
And may be closed by a closing member on the distal end side from the communication passage 26 to prevent the coolant liquid from leaking. In many cases, the machining of the machining tool 10 becomes easier. Further, in the present embodiment,
Although the grindstones 22 and the chips 32 are provided six by six, the number thereof may be five or less, and particularly when the body has a small diameter, it is desirable to provide four.

In the above embodiment, since the grindstone 22 is an electrodeposited grindstone, even if the abrasive grains of the grindstone are separated, the grindstone can be reused as the grindstone by electrodepositing the abrasive grains again. However, the grindstone 22 may be other than the electrodeposited grindstone, and the grindstone portion 20 may be configured to have a plurality of grindstone pieces 72. Specifically, for example, as shown in FIGS. 11 to 13, six grooves 74 extending in the axial direction are formed at equal angular intervals on the outer peripheral surface of the body 16, and the grindstone pieces 72 are fixed to the grooves 74. Thus, the grindstone portion 20 is configured. The grindstone piece 72 is formed by hardening CBN or diamond abrasive grains with a binder, and the portion of the grindstone piece 72 where the abrasive grains are fixed protrudes from the groove 74, and the diameter of the grindstone portion 20 including the grindstone pieces 72 is The diameter is slightly larger than the diameter of the reamer 30. In FIG. 11, a part of the grindstone piece 72 is omitted for easy understanding.

In the present working tool, the coolant holes 18
Are formed, and a communication passage 76 communicating from the coolant hole 18 to the outer peripheral surface of the grindstone portion 20 is formed. Communication passage 7
6 is opened at a portion other than the groove 74 of the grindstone portion 20,
The opening is a coolant outlet 77. In this machining tool, the reaming part 30
A communication passage 78 communicating with the reamer 30 is also formed, and the communication passage 78 opens at the bottom of the groove 34 of the reamer 30. According to this processing tool, the coolant liquid is satisfactorily supplied to both the grindstone section 20 and the reamer section 30 during the processing.

Further, as shown in FIG.
0 may be integrally formed of a cemented carbide and fixed to the tip end of the body 16 by brazing. Alternatively, as shown in FIG. 15, the entire processing tool 10 may be integrally formed of a cemented carbide, and the blade portion 90 may be directly formed on the outer periphery of the body 16 to form the reamer portion 92.

Further, as shown in FIG. 16, a reamer 100 integrally formed of a cemented carbide may be fixed to the tip of the body 16 by a bolt clamp. In this embodiment, a through hole 102 penetrating in the axial direction is formed in the reamer 100 and the through hole 1 is formed.
A tapered hole 104 having a bottom is formed at the rear of the hole 02. The tapered hole 104 is formed so as to have a larger diameter toward the rear end opening.
6 and is positioned by being fitted into the tapered portion 106 formed at the tip of the sixth. A female threaded hole 108 is formed in the tapered portion 106 and a bolt 110 is screwed into the female threaded hole 108 so that the reamer 1
00 is fixed to the body 16. According to this aspect, when the life of the grindstone portion 20 and the life of the reamer portion 100 are different, one can be replaced and used. The reamer 100 having a steel body and brazed with a carbide tip may be fixed to the tip of the body by a bolt clamp.

FIGS. 17 to 19 show a working tool 150 according to another embodiment of the present invention. This machining tool 150
1 has substantially the same configuration as the processing tool 10 in FIG. 1, but differs in that the tip of the reamer 30 and the grindstone of the grindstone section 20 are respectively attached at an angle to the axis. A groove 152 twisted to the left is formed in the reamer 151, and a cemented carbide tip 154 is fixed to the groove 152 by brazing. The main processing tool 150 includes a reaming part 151 having a so-called right-handed and left-handed blade 156.
And a grindstone portion 159 having a grindstone 158 twisted in the same direction as the blade portion 156. Also in the present embodiment, the front end of the grindstone 158 is formed so as to be located forward in the rotation direction with respect to the rear end of the tip 154. The magnitude of the deviation in the rotation direction of the grindstone 158 with respect to the tip 154 is the same as the magnitude of the deviation in the above-described embodiment. The grindstone 158 is also the same electroplated grindstone as the processing tool shown in FIG. Coolant hole 18 through body 16
Is formed, and is closed by the closing member 160 in the vicinity of the distal end, thereby preventing the coolant from leaking. A communication passage 26 communicating from the coolant hole 18 to the groove 24 of the grindstone part 159 is formed, and the groove 15 of the reamer part 151 is formed.
2 is formed. In the working tool 150, the coolant is supplied to the grindstone section 159 and the reamer section 151 during the working. In addition, blade part 1
56 may be formed in a left-handed right-handed twist, a left-handed twist, or a right-handed right-handed twist. The reamer 30 is configured by attaching the chip 154 to the groove 152 formed in the body 16, but may be configured in combination with the features of the above-described embodiments.

FIG. 20 shows a working tool 200 according to still another embodiment of the present invention. In the processing tool 200, the diameter of the grindstone portion 202 is adjustable. The main processing tool 200 is provided with a grindstone section 20 before processing the hole to be processed.
By adjusting the diameter of No. 2, it is possible to adjust the allowance by the grindstone portion 202. The configuration of the reamer 30 of the processing tool 200 is the same as that of the processing tool 10 in the above-described embodiment, but since the configuration of other parts is different, the different parts will be described in detail.

The working tool 200 has a shank 204 and a body 206, and has a center hole 208 penetrating the shank 204 and the body 206 in the axial direction. A grindstone part 202 is formed on the base end side of the reamer part 30 of the body 206. A plurality of rectangular elongated holes 210 extending in the axial direction are formed in the grindstone portion 202. The plurality of elongated holes 210 are, for example, four and are formed at equal angular intervals. Since the shapes of the long holes 210 are the same, one of them will be described as a representative.

The side faces of the elongated hole 210 facing each other are parallel. A steel slab 212 is fitted into the elongated hole 210 with substantially no gap and slidable in a direction perpendicular to the axis. The billet 212 has a height, which is a dimension in a direction perpendicular to the axis, larger than the depth of the elongated hole 210, and
0 protrudes from both the outer opening and the inner opening. A groove extending in the axial direction is formed on an outer side surface 214 of the steel piece 212 located outside the body 206, and a grindstone piece 215 is fitted into the groove without any gap, and is fixed by bonding. The grindstone piece 215 is partially projected from the steel piece, and the outer surface of the grindstone piece 215 is formed so as to form a part of a cylinder slightly larger in diameter than the body 206. Grooves 216 are formed near both ends in the axial direction of the billet 212, and annular grooves 218 are formed at corresponding positions of the body 206. The groove 218 is deeper than the groove 216, and the elastic rings 220, 2
22 are fitted respectively, and the billet 212 is
It is urged toward the inside of the body 206 by the elastic force of 20, 222. The elastic rings 220 and 222
It does not protrude outside the billet 212. The elastic rings 220 and 222 are made of, for example, a coil spring.

The center hole 208 of the body 206 is
02 having a relatively small diameter formed in front of 02
And a medium-diameter hole 226 having a relatively large diameter formed behind the grindstone portion 202. The small-diameter hole 224 and the medium-diameter hole 226 are connected by a tapered hole 228.
A tapered hole 228 is formed in a portion of the center hole 208 corresponding to the grindstone portion 202. Behind the middle hole 226 and inside the shank 204, the middle hole 2
Large diameter holes 230 having a diameter larger than 26 are formed, and the boundary between them is a shoulder surface 232 perpendicular to the axial direction. The shoulder surface 232 is provided on the shank 204 side from the boundary between the body 206 and the shank 204.

A tapered member 240 is fitted in the tapered hole 228 so as to be movable in the axial direction. The tapered member 240 has a tapered portion 244 having a tapered outer peripheral surface 242 and a shaft portion 246 extending from the rear end of the tapered portion 244 and slidably fitted to the medium diameter hole 226 with almost no gap. The minimum diameter portion that is the tip of the tapered portion 244 is formed smaller in diameter than the small diameter hole 224, and the maximum diameter portion that is the rear end of the tapered portion 244 is formed to have the same diameter as the shaft portion 246. A groove 248 is formed on the outer peripheral surface of the shaft portion 246 along the axial direction.
When the pin 250 fixed to the body 206 is engaged with the body 206, the taper member 240 cannot be rotated with respect to the body 206. The inner side surface 252 of the steel slab 212 is in contact with the tapered outer peripheral surface 242. Inner surface 252 of billet 212
Are formed along the tapered outer peripheral surface 242. As described above, since the billet 212 is urged toward the inside of the body 206 by the elastic rings 220 and 222, the inner surface 252 of the billet 212 is always tapered on the outer peripheral surface 24.
It is in contact with 2. This allows the taper member 240
The amount of protrusion of the billet 212 protruding from the body 206 is adjusted by the axial position. In other words, the billet 212
The amount of protrusion from the outer peripheral surface of the body 206 is uniquely determined by the elastic rings 220 and 222 and the tapered member 240.

Behind the tapered member 240, the tapered member 2
Axial position adjusting device 270 for adjusting the axial position of forty
Are arranged. The axial position adjusting device 270 has a rotating shaft 272 extending in the axial direction inside the medium diameter hole 226. A male screw part 274 is formed at the tip of the rotating shaft 272, and the male screw part 274 is screwed into a female screw hole 276 formed in the tapered member 240. The male screw part 274 and the female screw hole 276 cooperate to convert the rotational movement of the rotary shaft 272 into the axial movement of the tapered member 240.
Is composed.

The rear end of the rotating shaft 272 has a flange 2
80 is formed, and the flange portion 280 abuts against the shoulder surface 232 to restrict the rotation shaft 272 from moving forward in the axial direction. Hexagon hole 2 on the rear end face of the flange 280
82 is formed, and a hexagonal bar wrench (not shown) is engaged with the hexagonal hole 282 to rotate the rotation shaft 272. A female screw hole 284 having a slightly larger diameter than the flange portion 280 of the large-diameter hole 230 is formed, and a male screw member 286 is screwed into the female screw hole 284. The male screw member 286 is screwed until its head portion 287 contacts the rear end surface of the shank 204, and the front end surface 288 comes very close to the rear end surface 290 of the flange portion 280, so that the shaft of the rotary shaft 272 is rotated. Prevent backward movement in the direction.
A through hole 292 is formed in the male screw member 286 so as to penetrate in the axial direction, so that the above-mentioned hexagonal wrench can be inserted.
Note that a rolling thrust bearing is provided between both end surfaces of the flange portion 280, the shoulder surface 232, and the male screw member 286, and a preload in the axial direction is applied to the rolling thrust bearing. Can be defined with higher accuracy.

With the above configuration, the rotational movement of the rotating shaft 272 is converted into the axial movement of the tapered member 240, and the steel slab 212 is moved in a direction to project from the body 206 by the advance of the tapered member 240, or Taper member 2
By retreating 40, billet 212 is moved in a direction to be drawn into body 206. At a position corresponding to the flange portion 280 of the shank 204, a female screw hole 294 penetrating the shank 204 in the diameter direction is formed. A set screw 296 is screwed into the female screw hole 294, and the rotation of the rotary shaft 272 is prevented by pressing the flange portion 280 against the inner peripheral surface of the large-diameter hole 230.
The positions of the twelve bodies 206 with respect to the body 206 are fixed. In addition,
Adjustment of the amount of protrusion of the steel slab 212, that is, adjustment of the diameter of the grindstone portion 20, is performed before processing is performed, and the diameter is fixed during processing. The diameter of the grindstone portion 202 is adjusted to be slightly larger than the diameter of the reamer portion 30.

In the working tool 200, the rotating shaft 27
2 and the taper member 240 are formed with coolant holes 18 respectively, and a coolant liquid is ejected from a coolant ejection port formed in the vicinity of the steel slab 212 of the body 206. This configuration is substantially the same as that of the above-described embodiment. Description is omitted because there is.

FIGS. 21 and 22 show a working tool 300 according to still another embodiment of the present invention. This processing tool 300 has a drill part 302. As shown in FIG. 22, a drill portion 30 is attached to the tip of a body 304 made of cemented carbide.
2 are provided integrally, and a reamer part 306 is provided adjacent to the drill part 302. The grindstone portion 20 is provided behind the reamer portion 306 of the body 304. Since the grindstone portion 20 has the same configuration as the processing tool 10 of FIG.
Illustration and description are omitted.

The drill portion 302 is generally formed in the shape of a prism having a square cross section, and has a pair of main grooves 310 and a pair of sub-grooves 312 extending in the axial direction. The pair of sub-grooves 312 are formed shallower than the main groove 310 at a phase separated by about 90 degrees from each of the main grooves 310. The pair of main grooves 310 are formed symmetrically with respect to the axis,
A part of one side surface of the main groove 310 forms a rake surface 314. A flank 316 is formed at the tip of the drill portion 302, and a first main cutting edge 318 is formed by a line of intersection between the flank 316 and the rake face 314. A first sub cutting edge 319 is formed along the main groove 310, continuing from the first main cutting edge 318. The drill portion 302 of the working tool 300 is a straight-edged drill. A second cutting surface 320 is formed behind the first sub cutting edge 319 in the rotation direction (counterclockwise in FIG. 20), and the second cutting surface 320 is formed by two planes parallel to the axial direction. I have.

At the base end side of the drill part 302, a drill part 3
A reamer portion 306 is formed adjacent to 02. The reamer 306 is also formed integrally with the body 304.
The above-mentioned pair of main grooves 310 and the pair of sub-grooves 312 are formed continuously up to the reamer portion 306, and the grooves 310 and 3 are formed.
A first blade portion 330 and a second blade portion 331 are formed along 12. The reaming part 306 of the working tool 300
It has four blades 330, 331. The diameter of the reamer 306 is slightly larger than the diameter of the drill 302. A first main cutting edge 332 is formed along the main groove 310 at a portion of the tip of the reamer portion 306 whose diameter continuously increases, and a first sub cutting edge 334 is formed continuously therefrom. Further, a second main cutting edge 336 is formed along the sub-groove 312 at the tip end of the reamer portion 306, and a second sub-cutting edge 338 is formed continuously from the second main cutting edge 336. Each of the blades 330 and 331 has a main cutting edge 332 and 336 formed at the tip and a sub cutting edge 33 extending along the outer periphery.
4,338. The grindstone portion 20 is formed on the base end side of the reamer portion 306. This whetstone part 20
Is substantially the same as the machining tool 10 described above, and therefore illustration and description are omitted.

According to the working tool 300, the reamer 30
Since the drill portion 302 is formed on the tip side of 6, the reamer portion 306 as well as the grindstone portion 20 is guided well, and it is easy to further improve the processing accuracy. Further, since the pre-drilling, reaming and grinding can be performed in one step, the processing efficiency can be further improved.

Although some embodiments of the present invention have been described in detail above, these are merely examples, and the present invention is described in the above section [Problems to be solved by the invention, means for solving problems and effects]. The present invention can be implemented in various modified and improved forms based on the knowledge of those skilled in the art, including the described embodiment.

[Brief description of the drawings]

FIG. 1 is a front view showing a working tool according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line II-II in FIG.

FIG. 3 is a side view of the working tool.

FIG. 4 is a perspective view showing a main part of the working tool.

FIG. 5 is a front view showing a conventional finishing reamer.

FIG. 6 is a side view of the reamer.

FIG. 7 is a graph showing a transition of a processing diameter as a result of a comparative experiment between the processing tool and a reamer.

FIG. 8 is a graph showing changes in surface roughness in the comparative experiment.

FIG. 9 is a graph showing transition of roundness in the comparative experiment.

FIG. 10 is a graph showing the straightness of the comparative experiment.

FIG. 11 is a front view showing another embodiment of the working tool.

FIG. 12 is a side sectional view of the working tool.

FIG. 13 is a side view of the working tool.

FIG. 14 is a front view showing still another mode of the working tool.

FIG. 15 is a front sectional view showing still another embodiment of the working tool.

FIG. 16 is a front sectional view showing still another embodiment of the working tool.

FIG. 17 is a front view showing a working tool according to another embodiment of the present invention.

FIG. 18 is a side sectional view of the working tool.

FIG. 19 is a side view of the working tool.

FIG. 20 is a front sectional view showing a working tool according to still another embodiment of the present invention.

FIG. 21 is a side view showing a working tool according to still another embodiment of the present invention.

FIG. 22 is a front view of the working tool.

[Explanation of symbols]

 10, 150, 200, 300: machining tool 18, 55: coolant hole 20, 202: grinding stone part 30, 80, 90, 100, 306: reamer part 302: drill part

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Akio Fukui 26, Hirako, Yoshiwara-cho, Toyota-shi, Aichi Prefecture Inside Fuji Seiko Co., Ltd. (72) Inventor Akinori Iwa 3 Hamacho, Hekinan-shi, Aichi Prefecture Toyota Motor Corporation (72) Inventor Norihisa Ohno 3 Hamacho, Hekinan-shi, Aichi F-term in Toyota Industries Corporation (Reference) 3C050 EB06 EB07 EB08 EB09 3C063 AA10 AB03 AB08 BB02 BG04 CC12 EE21

Claims (5)

[Claims] 1. A processing tool which has a generally axial shape, has a reamer portion at a distal end side in an axial direction, and a grindstone portion at a base end side thereof, and an outer diameter of the grindstone portion is slightly larger than an outer diameter of the reamer portion. A machining tool, wherein the reamer portion has at least one reamer groove extending in a direction including at least an axial component, and the reamer groove is terminated before the whetstone portion. . 2. A processing tool having a generally axial shape, having a reamer portion at the distal end side in the axial direction and a grindstone portion at the base end side thereof, wherein the outer diameter of the grindstone portion is slightly larger than the outer diameter of the reamer portion. Wherein the reamer portion includes at least one reamer groove extending in a direction including at least an axial component, and the grindstone portion includes at least one grindstone groove extending in a direction including at least an axial component. The end of the reamer portion side of the rear end edge in the rotation direction of the grindstone groove is offset forward in the rotation direction from the end of the rim portion of the rear end edge in the rotation direction of the reamer groove. Processing tool to do. 3. A processing tool having a generally axial shape, having a reamer portion at the distal end side in the axial direction and a grindstone portion at the base end side thereof, wherein the outer diameter of the grindstone portion is slightly larger than the outer diameter of the reamer portion. Wherein the reamer portion includes at least one reamer groove extending in a direction including at least an axial component, and the grindstone portion includes at least one grindstone groove extending in a direction including at least an axial component. A machining tool, wherein the grindstone groove is communicated with the reamer groove and shallower than the reamer groove. 4. The processing tool according to claim 2, wherein the reamer portion and the grindstone portion each include a plurality of the reamer groove and the grindstone groove. 5. A coolant passage having a coolant passage extending substantially in the axial direction therein and an ejection hole extending from the coolant passage and opening at least on an inner surface of the grindstone groove. The processing tool according to any one of the above.