JP2004066435A - Honing tool and method of honing using the tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a honing tool that can perform honing precisely and efficiently and provide a method of honing using the tool. <P>SOLUTION: This honing tool 1 used for honing with a small diameter hole has a grinding main portion where abrasive grain 11 is distributed in a manner that each grain 11 is spaced away at an interval of at least one grain diameter and more and a root portion fixed to the tool base material (base metal) using a metallic bond material. Also, grinding scraps are removed and the grinding precision is improved by adding oscillation movement as well as rotating using the honing tool, with an synergistic effect of a distribution state of the grind 11 of the tool 1 and oscillation movement. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
INDUSTRIAL APPLICABILITY The present invention is capable of efficiently and accurately honing a workpiece mainly made of a soft metal such as stainless steel, aluminum alloy, copper or copper alloy to which grinding dust easily adheres to abrasive grains during grinding. The present invention relates to a honing tool and a honing method using the honing tool.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, a drill having a reamer or a diamond cutting edge attached thereto has been used for high-precision drilling of a workpiece such as stainless steel, aluminum alloy, copper or copper alloy.
[0003]
In order to obtain a precise finish when drilling holes in a workpiece, honing is mainly performed. Compared to other precision finishing processes, this honing process has the advantages that high-precision machining is possible without relying on the precision of machine tools and that straightness is easily obtained in addition to roundness. ing. Therefore, it is often used for finishing of inner surfaces such as cylinders and linear holes.
[0004]
There have already been many proposals for the technology to perform such honing, and in order to increase the roundness and straightness efficiently by processing, a method of rotating the grindstone and reciprocating linearly is adopted. Have been. Such a technique is known, for example, from Japanese Patent No. 30833787 and Japanese Patent No. 2900027.
[0005]
In the honing method and the honing apparatus disclosed in Japanese Patent No. 30833787, the honing is performed while superimposing a minute rotational vibration on a rotational motion of a honing tool, and a hole diameter surface of a workpiece. A rotating main shaft that can rotate around the axis of the shaft and reciprocate in the axial direction, and a device that includes means for superimposing fine vibrations on the rotating main shaft, and a honing tool is attached to the rotating main shaft. It is described that machining accuracy can be increased by adding fine vibrations to the rotating motion and the reciprocating motion.
[0006]
Further, in the device disclosed in Japanese Patent No. 2900027, as a honing device for mainly precision-finishing the inside diameter of a small diameter tapered hole or blind hole shallow hole, reciprocating motion can be performed simultaneously with rotary motion. A honing device with a cam mechanism is described.
[0007]
[Problems to be solved by the invention]
However, in the case of using a reamer or a drill for drilling a workpiece made of a soft metal such as stainless steel, aluminum alloy, copper or copper alloy, chips (chips) may adhere to the cutting edge. In addition, it is difficult to finish with high precision and high efficiency because of the formed cutting edge. Also, in the drilling of workpieces with a soft metal that grind chips tend to adhere to the abrasive grains during grinding, the diamond or CBN abrasive grains are ground using a tool that is electrodeposited on a grindstone arbor of a metal base material. Then, since the distribution of the abrasive grains is non-uniform and the abrasive grains are in contact with each other, the grinding swarf removed by the abrasive grains is hardly caught between the abrasive grains and hardly peeled off. As a result, the grinding stone (tool) There is a problem that the grinding dust of the powder adheres to the surface of the metal and adversely affects the processed surface, thereby deteriorating the processing accuracy.
[0008]
Also, in the honing process, as in the above-described prior art, when a reciprocating motion is added to the rotary motion to grind (polish) the work surface of the workpiece with the abrasive grains, the cutting chips adhere to the abrasive grains. However, in the current tool, cutting chips are liable to adhere to the abrasive grains, and the deterioration of processing accuracy due to the adhesion of the cutting chips is inevitable.
[0009]
In particular, when honing a small-diameter hole, as described above, it is difficult to perform high-precision processing with a tool having a continuous blade such as a reamer or a drill with a diamond cutting edge. In the processing, furthermore, the distribution state of the abrasive grains in the grinding portion has not been made effective, and it is difficult to perform the processing with high accuracy and high efficiency.
[0010]
SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and a small-diameter hole in a soft alloy metal work such as stainless steel, an aluminum alloy, copper or a copper alloy can be formed with high accuracy and high efficiency. It is an object of the present invention to provide a honing tool that can be machined and a honing method using the tool.
[0011]
[Means for Solving the Problems and Functions / Effects]
In order to achieve the above-mentioned object, a honing tool according to the first invention is provided.
A honing tool used for honing a small-diameter hole, wherein a grain size distribution of abrasive grains in a main part of the grinding is arranged at least at intervals of one or more of the abrasive grain diameter, and a base of the honing tool is attached to a tool base material by a metal bonding material. It is characterized by being fixed by.
[0012]
ADVANTAGE OF THE INVENTION According to this invention, the base part (base part) of an abrasive grain is fixed to a tool base material by a metal binding material, and it is made for a metal bonding material not to adhere to the front-end | tip protrusion part of the abrasive grain which contributes to a process. And, by arranging the abrasive grains apart from each other, when the surface to be ground of the workpiece is ground at the time of honing processing, the grinding debris removed by the abrasive grains pass through between the abrasive grains and are removed. That is, even a soft and highly adherent metal can be easily discharged by the coolant used during grinding, and can be processed with high precision.
[0013]
In the above invention, it is preferable that the tapered portion is formed such that the tapered portion is formed so as to be inclined to the shank side from the portion having the maximum diameter of the tool, and the leading end portion is provided with an introduction gradient portion (second invention). Further, it is preferable that the peripheral surface is divided into a plurality and a portion to which no abrasive particles are attached in the axial direction is formed in the abrasive particle attachment range from the tip to the shank (third invention).
[0014]
With this configuration, the surface to be machined is gradually cut at the tip having the introduction gradient, and the grinding chips are ground to the required size at the largest diameter portion while the grinding chips are subdivided, and the grinding chips thus ground are removed from the maximum diameter portion. Even if it moves to the shank side, since the clearance gradient is formed, it can be removed without damaging the processed surface at that portion. In addition, since a plurality of portions without abrasive grains are provided in the axial direction, if such portions are formed in grooves, the grinding debris flows into those grooves and the effect of exclusion to the outside. Can be further increased.
[0015]
In the above invention, it is preferable that the abrasive grains are fixed to the base material in a single layer with a metal bonding material in a portion where the abrasive grains adhere from the tip of the tool to the shank (fourth invention). With such a configuration, the abrasive grains can be securely fixed to the base material at the base portion, so that the effect of increasing the durability without easily peeling the abrasive grains can be obtained. In addition, the particle size distribution of the abrasive grains in the order of grinding can be selectively arranged, and the performance as a tool can be improved.
[0016]
A fifth aspect of the present invention is a honing method comprising performing one-pass grinding by applying an oscillation motion while rotating using the honing tool according to the first to fourth aspects.
[0017]
According to the present invention, by giving the oscillation motion while rotating the tool according to the above invention, the distribution of the abrasive grains is relatively coarse as described above, and a tool with a relief angle at a portion connected to the main part By using, grinding chips that are likely to adhere to the abrasive grains can be separated from the abrasive grains and can be efficiently discharged, and the effect of improving the grinding accuracy can be obtained even for a workpiece with difficult workability. .
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, specific embodiments of the honing tool according to the present invention will be described with reference to the drawings.
[0019]
FIG. 1 is an overall side view showing an embodiment of a honing tool according to the present invention. FIG. 2 is an enlarged view as viewed from A in FIG. 1, FIG. 3 is an enlarged cross-sectional view of a main part, and FIG. 4 is a partial plan view showing an enlarged distribution of abrasive grains.
[0020]
The honing tool 1 of the present embodiment (hereinafter, simply referred to as a tool 1) is used for honing a small-diameter hole 21 in a workpiece 20, and as shown in FIG. The grinding portion 2 having a grinding function has a tip portion 3 having a tapered shape, and a required section connected to the tip portion 3 has a maximum diameter to form a main grinding portion 4. A slightly sloping finish grinding portion 5 is formed towards the side and is formed integrally with a shank 7 of the required length via a base 6.
[0021]
Further, in the tool 1, as shown in FIG. 2, on the peripheral surface of the grinding portion 2, a plurality of grooves 9 are substantially equally divided and engraved from the tip to the base in the axial direction. . Therefore, the peripheral surface of the grinding portion 2 is formed in a state separated by the groove 9. The grooves 9 serve to discharge grinding chips generated during grinding.
[0022]
The grinding portion 2 of the tool 1 is provided on a peripheral surface of a tool base material (base metal 10, stainless steel is used in this embodiment) with abrasive grains such as diamond abrasive grains and CBN (cubic boron nitride) abrasive grains. 11 are fixed in a required distribution state. The abrasive grains 11 used in this embodiment have a grain size of # 50/60 and a grain size of 0.25 to 0.3 mm.
[0023]
As shown in FIG. 4, the distribution state of the abrasive grains 11 in the grinding portion 2 is such that a large number of rows are arranged in the circumferential direction at intervals of at least one grain size of the abrasive grains 11, and the axial arrangement of the respective rows Are arranged so that the abrasive grains in the other row are slightly displaced with respect to one row. The arrangement of the abrasive grains 11 is not particularly limited, but it is preferable that the interval P ′ in the axial direction is larger than the interval P in the rotation direction. By forming the arrangement of the abrasive grains along the peripheral surface in this manner, the abrasive grains 11 in each row during rotation are arranged in an apparently continuous state.
[0024]
In order to fix the abrasive grains 11 to the base metal 10 in the distribution state, first, as a metal bonding material (brazing material 12), for example, Ni brazing (component 2.0% B , 3.5% Si, the remaining Ni) to a thickness of about 50 to 80 μm, and is adhered to the surface of the grinding unit 2 with an adhesive (not shown). Thereafter, a flammable thin holding material (not shown), such as a paper sheet or a plastic film, which previously arranges and holds the abrasive grains 11 on the Ni brazing foil surface as described above, is wound and fixed with an adhesive. Let it. As for the distribution arrangement of the abrasive grains 11, an adhesive surface of the abrasive grains is formed by a separate tool having an opening in which a pattern is determined, and the abrasive grains are attached to the adhesive surface.
[0025]
When the brazing material 12 and the flammable holding material (paper sheet, plastic film, etc.) of the patterned abrasive grains 11 are fixed to the surface of the required portion of the base metal 10 in this manner, after the adhesive is cured, (To about 400 ° C.) to incinerate the holding material of the abrasive grains. At the same time, the brazing material 12 is softened and the abrasive grains 11 are held along the pattern. This can prevent the brazing material 12 and the abrasive grains 11 from falling off and segregating. Further, the brazing material 12 is heated to about 100 ° C. before the melting point, and is held for about 5 to 10 minutes. In this case, the entire base metal 10 is heated to a temperature close to the melting point of the brazing material 12, and uneven heating of the base metal 10 can be prevented. Thereafter, the brazing material 12 is heated to the melting point of the brazing material 12 at a stretch and held for about 3 minutes, and then cooled, so that the brazing material 12 is surely melted, and the abrasive grains 11 are fused to the base metal 10, and the overheating is caused. Excessive flow of the molten brazing material can be prevented, and the abrasive grains 11 can be securely fixed to the base metal 10.
[0026]
In the tool 1 of the present embodiment thus obtained, the abrasive grains 11 are fixed to the base metal 10 by the brazing material 12 at the ground portion in the grinding section 2 in the above-described pattern, and the tips of the abrasive grains 11 are brazed. It is arranged in a single layer without being covered by the material 12.
[0027]
In addition, in the tool 1 of the present embodiment, the tip portion 3 of the grinding portion 2 is tapered so that the main grinding portion 4 to be connected has a maximum diameter, and the distribution density of the abrasive grains 11 formed on the peripheral surface portion thereof. Is denser than the other parts (however, the pattern is maintained), and the distribution density becomes slightly coarser than the main grinding part 4 in the finish grinding part 5 with a slight relief gradient thereafter. Formed. In this way, the surface to be ground of the workpiece 20 can be effectively ground with high precision and high efficiency as described later.
[0028]
Next, a processing method using the tool 1 will be described. As an embodiment of the present invention, a description will be given of hole machining in a workpiece 20 made of aluminum alloy.
[0029]
In this embodiment, the shank 7 of the tool 1 is mounted on a tool head of a grinding machine (honing machine) having an axial oscillation movement mechanism, and is rotated at a required rotation speed (about 1000 rpm). The tool 1 is made to enter the to-be-ground hole 21 of the workpiece 20 from the grinding portion tip portion 3 of the tool 1 while performing an oscillation motion (about four times per rotation).
[0030]
When machining under the above-described conditions, the surface to be ground of the workpiece 20 has a tapered tip portion 3 serving as a guide for the introduction of the tool 1, and a required machining diameter by the main grinding portion 4 with the axis aligned. Is removed. At this time, the countless abrasive grains 11 fixed to the outer peripheral surface of the grinding portion 2 of the tool 1 are such that the distance between the fixed abrasive grains is one or more of the maximum diameter of the abrasive grains 11 as described above. Since they are arranged and are arranged side by side so as to be continuous in the rotating direction (axial direction), grinding chips are ground without remaining between the abrasive grains. Then, as the tool 1 moves in the axial direction, it is uniformly ground.
[0031]
In this grinding portion, a function is provided such that the surface to be ground is dug up at the tip of the abrasive grains 11 by the rotation and the oscillation motion of the tool 1, and since the gap between the abrasive grains is widely arranged, the grinding dust is removed. Is not retained between the abrasive grains, and is eliminated because a plurality of grooves 9 are provided in the circumferential direction and the grinding portion 2 having the abrasive grain-adhering surface intermittently comes into contact with the surface to be ground. The grinding chips to be removed move together with the coolant used during the processing to the groove 9 and are discharged to the outside.
[0032]
Further, when the tool 1 further enters, since all of the grinding waste generated by the grinding by the main grinding portion 4 cannot be transferred to the groove 9, there is a case where the tool 1 is transferred to the finish grinding portion 5 as the tool 1 moves. However, since the finish grinding portion 5 is shaped so as to be inclined toward the shank 7 side with respect to the main grinding portion 4 and at the same time, the distribution density of the abrasive grains 11 is roughened as compared with the former. Grinding chips that move while attached to the base metal 10 do not adhere to the abrasive grains 11 again. Therefore, the ground surface is not damaged by being brought into contact with the previously ground surface, and is ground again by the abrasive grains 11 arranged on the peripheral surface of the finish ground portion 5 to be precisely finished.
[0033]
In this manner, according to the grinding by the tool 1 of the present embodiment, the distribution of the abrasive grains 11 disposed on the tool 1 by moving the tool 1 by a required distance, in other words, the grinding dust is reduced by the abrasive grains. By using the oscillation motion together without generating a residual phenomenon that does not fill the gap, the grinding function is synergistically improved. As a result, it is possible to obtain an effect that a high-accuracy honing process with high roundness can be performed by making the tool 1 one-pass.
[0034]
In the above description, a plurality of grooves are distributed and formed in the axial direction on the outer peripheral surface of the tool. However, when the diameter of the tool is smaller (small diameter), the groove is mounted on the base. Since such a small diameter (for example, φ4 mm or less) cannot be engraved on gold, for example, as shown in an enlarged cross-sectional view in FIG. By providing a portion 15 (groove-corresponding portion) where the abrasive grains 11 are not disposed at a required length in the axial direction, grinding chips are moved to a blank portion of the groove-corresponding portion 15 so as to be flowed and discharged by the coolant. can do.
[0035]
By the way, the grain size of the abrasive grains that can be employed in the honing tool according to the present invention can be those of # 20 to # 1000. The spacing between the abrasive grains is preferably 2 to 5 times the grain size.
[Brief description of the drawings]
FIG. 1 is an overall side view showing an embodiment of a honing tool according to the present invention.
FIG. 2 is an enlarged view of FIG.
FIG. 3 is an enlarged sectional view of a main part.
FIG. 4 is a partial plan view showing an enlarged distribution of abrasive grains.
FIG. 5 is an enlarged sectional view of a main part of a honing tool having a very small diameter.
[Explanation of symbols]
1 tool (Honing tool)
2 Grinding part 3 Tip part of the grinding part 4 Main grinding part of the grinding part 5 Finish grinding part of the grinding part 7 Shank 9 Groove 10, 10A Base metal 11 Abrasive grain 12 Brazing material 15 Groove equivalent part

Claims (5)

A honing tool used for honing a small-diameter hole, wherein a grain size distribution of abrasive grains in a main part of the grinding is arranged at least at intervals of one or more of the abrasive grain diameter, and a base of the honing tool is attached to a tool base material by a metal bonding material. A honing tool, which is fixed by a honing tool. The honing tool according to claim 1, wherein the honing tool has a structure in which a tapered portion is formed so as to be inclined to a shank side from a portion having a maximum diameter of the tool, and an introduction gradient portion is provided at a tip end. 3. The tool according to claim 1, wherein, in the tool, a portion where an abrasive grain is not attached in an axial direction is formed by dividing a peripheral surface into a plurality in an abrasive grain attachment range from a tip to a shank. 4. Honing tool. The honing according to any one of claims 1 to 3, wherein in the tool, in a portion where the abrasive grains are attached from the tip to the shank, the abrasive grains are fixed to the base material in a single layer with a metal bonding material. tool. 5. A honing method comprising: performing one-pass grinding by applying an oscillation motion while rotating the honing tool according to claim 1;

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