JPS63283868A - Superabrasive grain boring tool - Google Patents

Abstract

PURPOSE:To maintain the superior cutting performance and carry out the boring work efficiently by using a network basic member as supporting basic member for abrasive grains and fixing abrasive grains by a resin group adhesive and constituting the basic member so that the opened ports of the network can be left. CONSTITUTION:Abrasive grains 6 are attached onto a network basic member 5 as supporting basic member for abrasive grains 6 by a resin group adhesive, and the basic member is constituted, leaving opened ports so that the clogging for the networks due to an abrasive grain fixing part 4 does not become over 75%. Therefore, a number of cutting edges consisting of the abrasive grains 6 projecting from the adhesive layer act, keeping buffer action performance for a workpiece. Further, since coolant can be supplied sufficiently through the opened networks, chips can be smoothly discharged, and clogging can be prevented, and the superior cutting performance can be maintained. Therefore, the boring work with high efficiency can be carried out.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention is a superabrasive using so-called superabrasive grains such as diamond or cubic boron nitride, in order to efficiently drill holes in various ceramics, cemented carbide, etc. This relates to a grain hole drilling tool.

(Prior art) Conventionally, JISB4
131 (diamond and cubic boron nitride wheels), various shapes such as flat, cup-shaped, and shafted wheels are used.

However, with the exception of electroplated grinding wheels, these superabrasive grinding wheels have a structure in which the grinding wheels are embedded in a metal bond, etc., and there is almost no protrusion of the abrasive cutting edge, making them difficult to use. In this case, it is necessary to sharpen frequently. Also,
Many of these grinding wheels are non-porous and do not have so-called chip hockets, which prevents sufficient removal of chips and supply of coolant, resulting in deterioration of the abrasive grains and grinding wheels and clogging due to the generation of processing heat. This caused a decrease in sharpness. Therefore, with these grindstones, drilling such as internal grinding is possible, but it has been difficult to perform grinding that leaves a so-called core due to machining of an annular groove.

(Problems to be Solved by the Invention) However, the core-remaining machining method is very advantageous in terms of machining efficiency, as recognized from the trepanning cutting method. For this reason, the development of a superabrasive drilling tool that can be applied to the core-remaining machining method has become a problem.

``Therefore, in the present invention, the abrasive grain density is high, the abrasive grain layer always acts intermittently on the workpiece, and
The present invention aims to solve the above-mentioned problems by providing a new superabrasive drilling tool that is improved so that a sufficient amount of coolant can be supplied and, accordingly, good sharpness can be maintained.

(Means for solving problems) The present invention has been made in view of the above points.

A mesh base material is provided at the annular end of the rod-shaped tool body, and abrasive grains mainly consisting of superabrasive grains such as Guyamondo and cubic boron nitride are fixed to the annular part of the mesh base material with an adhesive. The present invention provides a superabrasive drilling tool that is improved to include a fixed abrasive part.

That is, the mesh base material is made of inorganic fibers or organic synthetic fibers, and has a mesh size of 0.4 to 1.5+.
The intestine has a density of 10 to 30 mesh. In addition, the abrasive grain fixing portion contains superabrasive grains in an amount of 20ffffi% or more of the total abrasive grains, and these abrasive grains are bonded and fixed with a resin adhesive so as to wrap around the threads of the mesh base material, and the mesh The pores are not blocked by 75% or more.

(Function) The superabrasive drilling tool of the present invention uses a mesh base material as a supporting base material for the abrasive grains, and the abrasive grains are fixed with a resin-based adhesive while leaving openings in the mesh. A cutting edge made of a large number of abrasive grains protruding from the adhesive layer acts as a buffer against the workpiece, and a sufficient amount of cooling can be supplied through the open mesh. Therefore, chips are discharged smoothly, so there is no clogging, and good sharpness is maintained.

In addition, the superabrasive drilling tool of the present invention is characterized by the type of mesh base material,
Since the balance of the type and amount of adhesive, the adhesion density of abrasive grains, etc. can be adjusted, it can be applied to various workpieces and machining methods for zero and core remaining.

(Example) Hereinafter, an example of the superabrasive drilling tool of the present invention will be described with reference to the drawings.

In Figures 1 and 2, (1) is a tool body in the shape of a round bar, and the center attachment of this tool body (1) is through a hole (
A core member (3) that enables internal supply of coolant is screwed into the inside of the tool body (1), and a mesh base material (4) equipped with an abrasive fixing part (4) is provided around the outer periphery of the tool body (1). 5) is provided.

The core member (3) extends from a threaded portion (3C) provided with a tapered head (3a) and a channel (3b) for coolant, as shown in FIGS. 3(a) and (b). Become.

Then, as shown in Figure 2, the tapered head (
3a) and the annular gap between the tapered hole portion (2a) allows coolant to be supplied.

Further, the mesh base material (5) provided around the outer periphery of the tool body (1) is made of inorganic fibers or organic synthetic fibers, and is composed of one layer or a plurality of layers in a laminated state. In this case, the inorganic fibers constituting the mesh base material (5) are selected from, for example, glass fibers, carbon fibers, silicon carbide fibers, alumina fibers, mullite fibers, fully bent fibers, etc.
Examples of the organic synthetic fibers include aromatic polyamide fibers, nylon fibers, polyester fibers, vinylon fibers, phenolic m-fibers, and rayon fibers. These mesh base materials (5) are used alone, as a blend, or as a combination of the above-mentioned fibers. In the case of lamination, it is also possible to suitably combine different fibers.

The mesh base material (5) is shown enlarged in FIG. 4, and its mesh size is 0.4 to 1.5 cm, and the density of the vertical and horizontal threads is 10 to 30 cm. Mesh (725mm)
coarser than 10 meshes (1,5
With a mesh size of m+ layer or more, the distribution of abrasive grains that adhere to the surface of the mesh base material (5) becomes coarse, resulting in a decrease in sharpness.
It also lacks rigidity as a whetstone. In addition, if the mesh size is finer than 30 meshes and is 0.4 mm or less, the meshes will be blocked by the abrasive grains (8), making it difficult to achieve the desired effect of the present invention. Material (5)
When adding more tools, it is also possible to knurl the outer peripheral surface of the tool body (1) to increase the joint strength.

Further, in the abrasive grain fixing portion (4), the abrasive grains (θ) are fixed by a resin adhesive (7), as clearly shown in FIG. In this case, the abrasive grain (6) is.

The threads constituting the mesh base material (5) are wrapped in a single layer or in multiple layers and are fixed in such a way that the cutting edge protrudes, and the abrasive grain fixed part (
It is necessary that the pores of the mesh should not be filled up by more than 75% due to 4). This is a consideration based on the discharge of chips and sufficient supply of coolant when using the grinding wheel.

Further, the abrasive grains (8) used in the present invention are mainly so-called superabrasive grains such as diamond and cubic boron nitride. However, in the present invention, the abrasive grains (6) are coated on the mesh base material (5) as a supporting base material, so the abrasive grains (8
) can be made very dense. Therefore, depending on the material of the workpiece, by replacing some of the expensive superabrasive grains with general abrasive grains and using mixed abrasive grains containing at least 20% by weight of superabrasive grains, sufficient sharpness can be obtained. It can demonstrate durability. The general abrasive grains mentioned here are JIS
This refers to artificial abrasives such as alumina abrasives, silicon carbide abrasives, and alumina-zirconia abrasives as specified in R6111, as well as natural abrasives such as silica, garnet, and frundum.

Furthermore, the resin adhesive (7) used in the present invention is:
It is a liquid type and is selected from heat-resistant resin adhesives made of thermosetting resins such as resol type phenolic resin, modified phenolic resin, epoxy resin, and polyimide resin.
Used in combination with various fillers.

FIGS. 6 and 7 show a modification of the superabrasive drilling tool of the present invention, in which a mesh base material (5) is provided with an abrasive fixing portion (4) on the annular end surface of the tool body (1). It is designed so that it can be installed. The tool body (1) is provided with an annular coolant injection groove (8), and along with this,
Coolant is supplied to the mesh substrate (5) through a suitable number of injection holes (9).

In this case, the attachment strength of the mesh base material (5) to the tool body (1) is increased by the annular protrusion (10) provided on the tool body (1).

Moreover, FIG. 8 is a modification of FIG. 6, in which the tool body (1) and the mesh base material (5) are attached by forming irregularities on the annular end surface in order to increase the strength by other means. .

In addition, these mesh base materials (5) are applied in a laminated state in FIGS. 6 to 8, but the lamination is as follows.
Both cylindrical and annular shapes can be laminated, and an appropriate reinforcing material can be used to maintain the strength of the mesh base material (5). In this case, the reinforcing member is, for example, a thin metal plate (
(perforated or non-perforated), a synthetic resin thin plate, an FRP thin plate, an inorganic fiber, an organic synthetic fiber, or a mesh-like one made of thin metal wire.

Next, an example of the manufacturing process of the ultra-low grain drilling tool of the present invention will be explained.

(1) Resin adhesive (7) such as liquid phenolic resin on both the front and back sides of the cylindrical or annular mesh base material (5)
Apply an undercoat.

(2) Apply abrasive grains (8) to both the front and back surfaces of the mesh base material (5) at an appropriate width from the outer peripheral edge, and heat to dry the adhesive (7).

(3) Apply the above resin adhesive (7
) is applied as a topcoat and heated to dry and semi-cure the adhesive (7). At this time, the holes in the mesh are filled by the abrasive grains (8) and the top coat adhesive (7).
Avoid exceeding 5%.

(4) For those that have been dried and become semi-cured,
These are sandwiched between two fully bent disk molds, heated to completely harden the resin, and then taken out of the mold. After these steps, they are attached to the tool body (1) and superabrasive grains are removed. A drilling tool is configured.

A superabrasive grinding wheel according to another embodiment of the present invention uses a semi-hardened grindstone after the step (3) above or a grindstone after the step (0) above, and newly applies a resin adhesive (7). A plurality of impregnated and coated sheets are laminated in a shape and size according to the purpose, and hot press is applied using two metal disks or molds to completely cure the resin and integrate it into a cylindrical or annular shape. Abrasive grain fixing part (
The tool shape has a value of 0.

The above step (1) where the adhesive (7) is applied as an undercoat to the mesh base material (5).
Before step 1), if necessary, it is also effective to apply a similar adhesive (7) for the purpose of sealing or imparting rigidity to modify the base material.

In addition, in order to increase the rigidity of the super abrasive drilling tool,
Fine powder of silicon carbide abrasive or alumina abrasive, or molybdenum disulfide or graphite is applied to the parts other than the abrasive grain adhesion part (4) so that the thickness is the same as or less than that of the abrasive grain adhesion part (4). It is also effective to fix solid lubricant powder, etc., with an adhesive (7) of the same type as above.

(Example 1) As for the mesh base material (5), a 20-mesh leno weave made of glass m male having a thickness of 0.18 mm was used.

Then, this mesh base material (5) is impregnated with a resol type phenolic resin attractive agent mixed with a silica-based fine powder filler for the purpose of sealing and imparting rigidity so as not to block the mesh, and then heated. It was dried to form a cylindrical shape of 62 mm diameter x 20 mm.

Next, the same type of phenolic resin adhesive as above was applied as an undercoat to the entire surface, and then diamond abrasive grains having a particle size of #140/170 were spray-coated on both the inner and outer circumferences from the outer edge to lo■. Furthermore, after heating and drying the spray coating,
A phenolic resin adhesive of the same type as above was applied as a top coat and dried by heating to bring it into a semi-cured state. The obtained mesh base material (5) is attached to the tool body (1) as shown in FIGS. 1 and 2, and after the resin is completely cured by pressure heating, it is removed from the mold and placed on a predetermined drilling grindstone. And so. At this time, the mesh occlusion caused by the abrasive grains and adhesive was about 50%. In addition, the thickness of the abrasive grain fixing part (4) is
0.5 mgt, and the thickness of the part other than the abrasive grain fixing part (4) was 0.3 .

When this super-abrasive drilling tool was used to drill a hole in alumina ceramics with a thickness of 30 mm at a rotation speed of 200 rpm and a feed rate of 1/in, the coolant was sufficiently supplied to the grooved part and the grinding wheel was clogged. It was possible to perform machining without leaving any cores with extremely good sharpness.

(Example 2) In Example 1, after applying the top coat, 16 cylindrical sheets were heat-dried and semi-cured, and the resin was fully cured by hot pressing to a thickness of 10+ fat. After integrating and removing from the mold, this was attached to a tool body (1) as shown in FIGS. 6 and 7 to form a superabrasive drilling tool.

With this tool, a silicon nitride sintered body with a thickness of 30 mm is rotated at 4 rotations.
When wet grinding was performed at 20 rpm and a feed rate of 1 and 52 m/sin, coolant was sufficiently supplied to the grooved portion, and the grinding wheel was not clogged and grinding was possible with extremely good sharpness.

(Effects of the invention) The superabrasive drilling tool of the present invention having the above-mentioned embodiments has the following features:
When using it, a sufficient amount of coolant can be supplied to the processing area through the open mesh, and the discharge of chips is smooth and there is no clogging. It has excellent properties such as being firmly bonded and fixed to the material, sharply cutting, and lasting well, making it possible to perform efficient drilling work.

[BRIEF DESCRIPTION OF THE DRAWINGS] Fig. 1 is a front view showing an embodiment of the ultra-low grain drilling tool of the present invention, Fig. 2 is a sectional view, and Figs. 3 (a) and (b) show the core member. In the drawings, (a) is a front view, (b) is a side view, Fig. 4 is an enlarged plan view of the main part of the abrasive grain fixing part, Fig. 5 is a cross-sectional view, and Fig. 6 is a main part. FIG. 7 is a partially cutaway front view showing another embodiment of the super-abrasive drilling tool of the invention, FIG. 7 is a bottom view, and FIG. 8 is a partially cutaway showing a modification corresponding to FIG. 6. It is a front view. (1)...Tool body (4)...Abrasive grain fixing part (5)...Mesh base material (6)...Abrasive grain (7)...Adhesive patent applicant Toshiba Tungaloy Corporation Koyo Co., Ltd. Sozo Co., Ltd. Scientific drawings! 'I'tu Procedures Amendment (Method) May/7, 1988 Patent Application No. 1982-44686 2, Title of Invention Super Abrasive Drilling Tool 3, Relationship with the Person Who Makes the Amendment Case Patent Applicant Toshiba Tungaloy Co., Ltd. 1-7 Tsukagoshi, Saiwai-ku, Kawasaki City, Kanagawa Prefecture April 28, 1988 (Shipping date) 5. Figures 1 and 2 of the drawings subject to amendment 6, Contents of amendment

Claims (1)

[Claims] A mesh base material is provided at the annular end of the rod-shaped tool body, and an abrasive grain fixing part in which abrasive grains are fixed with an adhesive is provided in the annular portion of the mesh base material. In the super abrasive drilling tool, the mesh base material is made of inorganic fiber or organic synthetic fiber, and has an opening of 0.4 to 1.5 mm and a density of 10 to 30 mesh, The abrasive grains contain at least 20% by weight of superabrasive grains such as diamond or cubic boron nitride, and the abrasive grain fixing portion is made of a resin-based material such that the abrasive grains wrap around threads constituting the mesh base material. A super-abrasive drilling tool that is bonded and fixed with an adhesive, and that the holes in the mesh are not more than 75% full.