JPH0796416A - Electrodeposition reamer tool - Google Patents

Abstract

PURPOSE:To provide an electrodeposition reamer tool capable of machining with high machining efficiency and high precision, having a stable tool life and especially suitable for hole drilling in steel material. CONSTITUTION:At the time of electrodepositing abrasive grains 26 on a crest part 24 formed on a reamer main body, at least on a tapered part 21 subjected to rough machining, the abrasive grains are arranged on a rotating direction side 24a of the crest part 24 along a groove 23 in one row. On a straight cylindrical part subjected to finishing work the abrasive grains can be electrodeposited on the whole of the crest part 24. Chips produced by rough machining are all discharged into the groove 23, and they are neither accumulated nor deposited in gaps among the abrasive grains 26. Between the rotating direction side 24a of the crest part 24 and an opposite side 24b to the rotating direction, there is a step difference, and holding power of the abrasive grains 26 is improved.

Description

Detailed Description of the Invention

[0001]

The present invention relates to diamond or CB.
The present invention relates to an electrodeposition reamer tool in which abrasive grains for processing such as N (Cubic Boron Nitride) are electrodeposited on the surface.

[0002]

2. Description of the Related Art As an electrodeposition reamer tool in which abrasive grains are electrodeposited on the surface of a reamer tool body, a taper-shaped portion (having a straight or R-shaped cross section) and a finishing process for sequentially roughing from the tip of the reamer tool body. Equipped with a straight cylindrical shape part,
There is known an electrodeposition reamer tool in which a plurality of grooves extending in the longitudinal direction are formed on the outer peripheries of both shaped portions, and abrasive grains are electrodeposited on the portions other than the grooves, that is, on the ridges (for example, Japanese Patent Laid-Open No. Hei 2). -1
39115).

FIG. 6 shows an example of this kind of conventional electrodeposition reamer tool. A taper-shaped portion 1 for rough machining provided with a reamer tool body at its tip and a finish machining connected to this taper-shaped portion 1 are shown. A straight cylindrical portion 2 for use with a work processing portion, the work processing portion has a groove 3 extending in the axial direction, and the surface of a mountain portion 4 existing between the grooves 3 and 3 is made of diamond or CBN. Abrasive grains are electrodeposited. Also,
An oil supply hole 5 is provided at the center of the electrodeposition reamer tool and extends from the base end portion to near the boundary between the tapered shape portion 1 and the straight cylindrical shape portion 2.
A coolant hole 6 is formed obliquely toward the groove 3 located at the boundary between the tapered portion 1 and the straight cylindrical portion 2. Here, the groove 3 has a substantially U-shaped cross section as shown in FIG. 6B, and the coolant hole 6 is provided so as to open at a substantially central portion of the bottom surface of the groove 3.

When this electrodeposition reamer tool is used for cast iron, chips generated during processing are cut into short pieces, which are discharged without accumulating in the grooves 3 or the gaps between the abrasive grains. It can be continued. But,
When this is applied to a steel material, relatively long continuous chips are generated, and these chips are deposited or welded in the grooves 3 and the gaps between the abrasive grains, which deteriorates the accuracy of the machined surface of the hole, reduces the machining efficiency, and reduces the tooling efficiency. The problem of shorter life occurs.

In view of the above-mentioned problems of the conventional electrodeposition reamer tool, the applicant of the present invention can efficiently discharge chips even when used for steel materials and has a high working efficiency. Was developed and filed (Japanese Patent Application No. 4-263911)
issue). As shown in FIG. 7, this electrodeposition reamer tool has a taper-shaped portion 11 for roughing, in which a reamer tool body is provided at a tip portion, and a straight cylindrical-shaped portion 12 for finishing, which is connected to the taper-shaped portion 11. And a work processing part having a groove 13 extending in the axial direction,
This is almost the same as the conventional electrodeposition reamer tool in that abrasive grains such as diamond and CBN are electrodeposited on the surface of the mountain portion 14 existing between the grooves 13 and 13.
The cross section of the groove has a rounded shape, groove 1
3 and the crests 14 are twisted in the direction opposite to the tool rotation direction toward the tip, and the coolant hole 16 is in the tool rotation direction with respect to the diametrical direction of the oil supply hole 15 (arrow in FIG. 7B). (Shown by the arrow) and is inclined by θ in the opposite direction, and is opened in the even portion of the bottom surface of the groove portion 13 opposite to the tool rotation direction, and these are formed in the tapered portion 1
1 is set near the boundary between the straight cylindrical portion 12 and the straight cylindrical portion 12, and is set in the substantially central portion of the straight cylindrical portion 12, and so on.

According to the above-mentioned electrodeposition reamer tool, since the groove 13 has a round cross-section, chips accumulated there are easily discharged, and the coolant hole 16 is aligned with the tool rotating direction of the bottom surface of the groove 13. Since the coolant liquid is ejected toward this part where the chips are easily accumulated, the coolant is ejected toward this part, which is closer to the opposite side, so that the action of discharging the chips is stronger, and the groove 13 and the crest 14 are the tip ends. Since the shape is twisted in the direction opposite to the tool rotation direction as it goes to, the action of discharging the chips forward in the groove 13 works as the tool rotates. When this electrodeposition reamer tool was used to machine steel, the machining accuracy, processing efficiency, etc. could be improved to a considerable extent as compared with the conventional electrodeposition reamer tool.

However, when standard abrasive grains having a large variation in grain size are used, the height of the tip of the abrasive grains varies because no truing is performed in the taper-shaped portion 11 for rough machining. Not only the grains do not act uniformly on the surface to be processed, but the height of the abrasive grain tip electrodeposited near the center of the crest in the direction of rotation is When the height is higher than the height, long chips may be generated near the center of the mountain portion 14 instead of the end portion in the rotation direction, and these chips are not discharged to the groove 13 and are deposited or welded between the abrasive grains, resulting in machining accuracy or machining. It has been found that the efficiency is deteriorated and the tool life is shortened.

Therefore, following the electrodeposition reamer tool (see FIG. 8) of Japanese Utility Model Laid-Open No. 5-29629, the electrodeposition density of the abrasive grains in the tapered portion 11 for rough machining is lowered to reduce the abrasive grains in that portion. It was also considered to increase the gap between the grains so that the chips can be easily discharged to the groove 13 through the gap between the abrasive grains, but this means, even if there is some improvement, cannot be a fundamental solution. .

[0009]

In view of the above points, according to the present invention, all the chips generated in the taper-shaped portion for rough machining are discharged into the groove and deposited or welded in the gap between the abrasive grains. In addition, because the abrasive grains of the tapered shape act uniformly on the surface to be processed, it is possible to perform high-precision machining with high machining efficiency, have a stable tool life, and are particularly suitable for high-precision hole machining of steel materials. It is intended to obtain an electrodeposition reamer tool.

[0010]

Therefore, an electrodeposition reamer tool according to the present invention is provided with a taper-shaped portion for roughing and a straight cylindrical-shaped portion for finishing in order from the tip of the reamer body. A plurality of grooves facing the longitudinal direction are formed on the outer circumference, and in the electrodeposition reamer tool in which abrasive grains are electrodeposited on the crests existing between the grooves, at least the abrasive grains electrodeposited on the tapered portion are It is characterized in that they are arranged in a line along the groove on the rotation direction side of the mountain portion. The tapered portion may have a straight cross section or an R shape. Further, as a preferred aspect thereof, in the portion where the abrasive grains are arranged in a line in the mountain portion, the rotational direction side where the abrasive grains of the mountain portion are electrodeposited is low and the opposite side is formed high, and the step is preferably an electrode. The thickness is almost equal to or less than the thickness.

Further, in the present invention, the abrasive particles electrodeposited on the tapered portion are classified or sized, and the abrasive particles electrodeposited on the tapered portion are subjected to truing. As a preferred embodiment, it is possible to perform graining after truing the grains.

[0012]

In the present invention, since the abrasive grains electrodeposited on the tapered portion are arranged in a row along the groove on the rotational direction side of the crest portion, all chips in the tapered portion are directed in the rotational direction of the crest portion. And is discharged to the groove on the rotation direction side. This action is irrespective of whether the groove and the crest portion are straightly extended as shown in FIG. 6 or twisted as shown in FIG. 7, and the groove has a U-shaped or rounded cross section. It can be obtained regardless of the shape you have. Due to this action, the problems of deterioration of the accuracy of the machined surface of the hole due to the accumulation or welding of the chips in the gaps between the abrasive grains, the deterioration of the machining efficiency, and the shortening of the tool life are alleviated.

At the place where the abrasive grains are arranged in a line in the mountain portion,
When the rotational direction side where the abrasive grains are electrodeposited is formed low and the opposite side is formed high, the step receives the cutting force acting on the abrasive grains, so that the retaining force of the abrasive grains is improved. If the step is too large, there is a problem that chips are likely to be deposited on the part, but the problem can be solved by making the step approximately equal to or less than the electrodeposition thickness.

Further, in the present invention, the abrasive grains to be electrodeposited on the tapered portion are classified or sized, and the abrasive grains electrodeposited on the tapered portion are subjected to truing. By performing truing and then sharpening, etc., the abrasive grains in the tapered shape will act evenly on the surface to be processed, resulting in chips that are uniform in size, length, etc. and difficult to discharge. Does not occur, and the wear of each abrasive grain is made uniform and the tool life is improved.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The electrodeposition reamer tool of the present invention will be described in more detail below with reference to FIGS. First, Fig. 1
The electrodeposition reamer tool shown in FIG. 7 is a reamer main body of the type shown in FIG. 7 and the abrasive grains are electrodeposited thereon. The workpiece processing part of the reamer main body has an R-shaped tapered portion 2 for rough machining.
1 and a straight cylindrical portion 22 for finishing, and the groove 23 and the mountain portion 24 extending in the axial direction are twisted in the direction opposite to the tool rotation direction toward the tip, and the mountain portion 24 is in the rotation direction side 24a. Is low and opposite to the direction of rotation 2
4b is formed high. The step formed here is
The thickness is equal to or less than the thickness of the plating 25 to be electrodeposited.

The abrasive grains 26 are electrodeposited in a row along the groove 23 on the rotation direction side of the mountain portion 24 over the entire workpiece machining portion. Since the side 24b where the abrasive grains 26 are not electrodeposited is formed to be one step higher, it acts to receive the cutting force acting on the abrasive grains 26, and therefore the holding force of the abrasive grains 26 is improved.
In order to electrodeposit the abrasive grains 26 in a row on the rotation direction side 24a of the mountain portion 24, electrodeposition may be performed with the opposite side 24b and the groove 23 masked. It is preferable to use the abrasive grains 26 that have been classified or sized and have a substantially uniform grain size. After electrodeposition, as shown in FIG. 21 abrasive grains are sharpened to form a cutting edge.

The electrodeposition reamer tool shown in FIG. 3 uses a reamer main body in which a step is formed only within the range of the tapered portion 31 of the mountain portion 34, and in the tapered portion 31, the groove 33 is formed on the rotational direction side 34a. The abrasive grains 36 are electrodeposited in a row along the line, and in the straight cylindrical portion 32, the abrasive grains 36 are electrodeposited on the entire mountain portion 34.

4 and 5, a diamond electrodeposition reamer tool with a diameter of 23 mm is used, and the peripheral speed is 20 m / mi.
n, SCSi under the condition of finished surface roughness Rmax 6 μm
It is a result of reaming the Mn2H (HB250) steel material. 4 and 5, the embodiment uses the electrodeposition reamer tool shown in FIG. 3 with truing and dressing, and the comparative example uses the electrodeposition reamer tool shown in FIG. 7.

FIG. 4 shows the allowance on the horizontal axis and the feed rate on the vertical axis, and shows that the machining efficiency increases as the line moves to the upper right. As shown here, the electrodeposition reamer tools obtained in the examples of the present invention have higher working efficiency than the electrodeposition reamer tools in the comparative examples. Further, FIG. 5 shows the cutting length when the machining allowance is 0.1 mm / diameter and the feed rate is 0.2 mm / min. In other words, FIG. 5 shows the tool life of the electrodeposition reamer tool, whereas all the electrodeposition reamer tools obtained in the examples of the present invention have a stable and long tool life (10 m or more). , Some of the electrodeposition reamer tools of the comparative example become unusable (marked with ●) at an early stage.

[0020]

According to the electrodeposition reamer tool of the present invention, all the chips generated in the taper-shaped portion for rough machining are discharged to the groove on the rotation direction side, so that the chips can be easily forwarded by the coolant. It is possible to discharge the chips and the chips are not deposited or welded between the abrasive grains. Even if the electrodeposition reamer tool of the present invention is applied to a steel material in which chips extend relatively long, it is possible to perform hole drilling with high accuracy and high efficiency, and a long tool life can be stably obtained.

Further, the abrasive grains should be classified or sized, and the abrasive grains electrodeposited on the tapered portion should be trued. The grains act evenly on the surface to be machined, the size and length of the chips are uniform in rough machining, and there are no chips that are difficult to discharge. The effect of improving the life is obtained.

[Brief description of drawings]

FIG. 1 is a schematic front view (a) of a work processing part of an electrodeposition reamer tool according to an embodiment of the present invention and a cross-sectional view taken along the line AA.

FIG. 2 is a schematic cross-sectional view of a work processing portion of the electrodeposition reamer tool according to the embodiment of the present invention.

FIG. 3 is a schematic front view of a work processing part of an electrodeposition reamer tool according to another embodiment of the present invention.

FIG. 4 is a graph comparing machining efficiencies of electrodeposition reamer tools of Examples and Comparative Examples.

FIG. 5 is a graph comparing the lives of the electrodeposition reamer tools of the example and the comparative example.

FIG. 6 is a partial sectional front view (a) and an end view (b) of a conventional electrodeposition reamer tool.

FIG. 7 is a partial sectional front view (a), a sectional view (b), and a front view of a work processing portion of an electrodeposition reamer tool according to a prior invention.

FIG. 8 is a cross-sectional view of a work processing portion of a conventional electrodeposition reamer tool.

[Explanation of symbols]

 21, 31 Tapered portion for roughing processing 22, 32 Straight cylindrical portion for finishing processing 23, 33 Grooves 24, 34 Mountains 24a, 34a Rotation direction side of mountain portion 24b Opposite rotation direction of mountain portion 25 Electricity Plated plating 26, 36 Abrasive grains

Claims (6)

[Claims] 1. A taper-shaped portion for roughing and a straight cylindrical portion for finishing are sequentially provided from the tip of the reamer main body, and a plurality of grooves extending in the longitudinal direction are formed on the outer periphery of both the shaped portions. In an electrodeposition reamer tool in which abrasive grains for electrodeposition are electrodeposited on the crests existing between the grooves, at least the abrasive grains for electrodeposition electrodeposited on the tapered portion are lined up along the groove on the rotational direction side of the crests. Electroplated reamer tool characterized by being placed in. 2. A portion of the ridge portion where the processing abrasive grains are arranged in a line is formed such that the rotational direction side of the ridge portion where the processing abrasive grains are electrodeposited is low and the opposite side thereof is high. The electrodeposition reamer tool according to Item 1. 3. The electrodeposition reamer tool according to claim 2, wherein the step difference between the rotation direction side and the opposite side of the mountain portion is substantially equal to or less than the electrodeposition thickness. 4. The electrodeposition reamer tool according to claim 1, wherein the abrasive grains for electrodeposition on the tapered portion are classified or sized. 5. The electrodeposition reamer tool according to claim 1, wherein the processing abrasive grains electrodeposited on the tapered portion are subjected to truing. 6. After truing the abrasive grains for processing,
The electrodeposition reamer tool according to claim 5, characterized by being sharpened.