KR101797983B1 - Manufacturing method for Loop blade and band saw thereof - Google Patents

Abstract

The present invention relates to a method of manufacturing a band saw having increased life span by minimizing separation of diamond or CBN abrasive grains and a band saw produced thereby, A step of temporarily adhering an abrasive grain mixed with a binder to the base material, a masking step of attaching a masking tape to the abrasive grains adhered thereto, an abrasive-embossing step of pressing a portion of the abrasive grains on the masking tape by pressing on the masking tape with a pressure roller, A first electrodepositing step of performing electrodeposition coating to temporarily fasten the abrasive grains, a masking removing step of removing the masking tape, and a secondary electrodepositing step of electroplating the base material to fix the abrasive grains, and a band Present a saw.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a method of manufacturing a band saw,

The present invention relates to a method of manufacturing a band saw having increased lifetime by minimizing abrasion of abrasive grains such as diamond and CBN, and a band saw produced thereby.

A band saw is made by cutting a cutting edge in a metal strip that is easy to bend, and is used in connection with a dedicated sawing device. Cutting using a band saw has a wide setting range of the cutting edge of the cutting edge, and the metal strip, which is the base metal, has a large tensile strength and a large protruded area, which makes it possible to cut under various setting conditions. Accordingly, it is possible to cut various kinds of work materials and is widely used in industry.

The band saw must be replaced when consumed due to abrasion. Since the abrasive grains mainly fixed by electrodeposition form a single layer, they are quickly consumed depending on the hardness of the workpiece.

Sometimes the residual value of the workpiece can be important. In the case of semiconductor wafer materials and jewels, it is necessary to reduce the loss of workpiece due to the thickness of the band saw, and a precise cutting surface is required.

Korean Patent Publication No. 10-2011-0102890 (September 19, 2011) Korean Patent Publication No. 10-2014-0094548 (July 30, 2014)

The present invention aims to improve the life of the band saw and the cutting quality by making precise cutting operation while preventing abrasion of the band saw.

Other objects and advantages of the present invention will become apparent to those skilled in the art from the following detailed description.

According to an embodiment of the present invention, there is provided a method of manufacturing a magnetic recording medium, comprising the steps of: forming a groove by press-fitting a side surface of a base material in a loop shape; temporarily adhering an abrasive grain mixed with a binder to the base material; A masking step of attaching the tape, a pressing step of press-fitting a part of the abrasive grains into the base material by pressing on the masking tape with a pressure roller, a first electrodeposition step of electrodeposition coating to easily fix the abrasive grains, And a secondary electrodepositing step of electroplating the base material to fix the exposed abrasive grains.

Here, the depth of the groove may be smaller than the average diameter of the abrasive grains.

And may further include a post-treatment step of performing a heat treatment for 23 minutes to 27 minutes at 230 ° C to 260 ° C after the secondary electrodeposition step.

Meanwhile, the band saw is manufactured in accordance with such a manufacturing method, and irregular grooves are formed on the surface by voids of abrasive grains detached from the surface of the base material through the masking removing step.

According to the embodiment of the present invention, the life of the band saw is increased, and excellent cutting power can be exhibited for a long life span. The curved surface of the leading edge corner evenly separates the abrasive grains, thereby solving the problem of the conventional technique in which the abrasion of the corners is lost and the service life is reached.

The smooth joint of the base material prevents scratches and the like on the cutting surface of the workpiece, and prevents damage to the band saw due to stress concentration. The curved surface of the leading edge prevents the abrasion of the abrasive grain and enables a high level of cutting force to be exercised for a long time.

By forming grooves in the base material and fixing the abrasive grains thereon, it is possible to increase the efficiency of the cutting operation according to the arrangement of the abrasive grains and prevent the abrasion of the abrasive grains during use by fixing the abrasive grains. It is possible to further increase the cutting force by exhibiting the chip removing and cooling effect by the groove on the surface of the cutting layer.

The effects of the present invention will be clearly understood and understood by those skilled in the art, either through the specific details described below, or during the course of practicing the present invention.

1 is a block diagram of a band saw manufacturing method according to an embodiment of the present invention;
2 is a perspective view of a band saw according to an embodiment of the present invention;
3 is a view of a step of looping a base material.
4 is a view showing a step of polishing a front end portion of a base material.
5 is a view of a groove forming step;
FIGS. 6 to 8 are sectional views sequentially illustrating steps of manufacturing a band saw according to an embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other features and advantages of the present invention will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: FIG.

It should be noted, however, that the same reference numerals are used for the same or similar components throughout the drawings. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings are exaggerated representations of the accumulations of some configurations so that the configuration may be readily viewed.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and, therefore, are not to be construed as limiting the technical spirit of the invention. It is to be understood that the invention is not to be limited by any of the details of the description to those skilled in the art from the standpoint of a person skilled in the art that any or all of the drawings shown in the drawings are not necessarily the shape,

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a band saw according to an embodiment of the present invention; FIG. The method of manufacturing a band saw according to an embodiment of the present invention includes a groove forming step s1, an abrasive temporary attaching step s2, a masking step s3, an abrasive pressing step s4, a first electrodepositing step s5, A step s6 and a secondary electrodeposition step s7. It is possible to further perform the post-treatment step (s8).

Figure 2 shows the finished band saw 100. The band saw 100 has a cutting layer 30 formed by attaching abrasive grains to the front end of a base material 10 made of a metal material. The band saw 100 can be flexibly restored. The band saw 100 is used by hanging it on a sawing device (not shown).

Figs. 3 to 4 relate to a preparation step of processing the thin strip-like base material 10 into a loop shape. Specifically, the preparation step includes a welding joint step, a joint polishing step, and an edge surface processing step.

The base material 10 has a thickness of 0.2 mm to 0.4 mm and a width of about 5 mm. The base material 10 may be made of stainless steel or high carbon steel.

The welding step is a step of joining both end portions 11 of the base material 10 in a loop shape by welding. In connecting the both ends 11, it is possible to make a butt jointing method in which the thickness of the joint portion does not increase.

The joint polishing step is carried out to both edges 11 of the base material including the outer surface of the weld seam 12 so as to smoothly connect the weld seam 12 welded with the end of the base material 10 to both ends 11 of the base material. Polishing (or polishing) together.

The polishing of the outer surface is primarily intended to remove the reinforcing fur protruding outward beyond the end of the base material 10 by welding, and it is difficult to remove the reinforcing fur from the edge of the base material 10 due to misalignment of both end portions, It has the additional purpose of modifying its form.

As a result, the joints of both end portions 11 of the base material are smoothly connected to each other, so that scratches such as scratches can be prevented from being cut on the cutting surface of the workpiece, and stress is concentrated on the joint portions during the cutting operation, .

Figure 4 relates to the edge surface processing step. The edge curving step is a step of machining the edge of the front end portion of the base material 10 formed by the loop into the curved surface 13.

The tip end portion of the base material 10 is brought into contact with the forming groove 71 while rotating the polishing roller 70 having the concave molding groove 71 formed at the center thereof, (13). The curved surface 13 of the edge can be machined only on one side of the base material or on both sides of the base material.

Fig. 4 (b) shows a cross-section of the tip end of the band saw in which the cutting layer 30 including abrasive grains is formed after machining the edge into a curved surface 13. Fig. The block arrows indicate the direction in which the band saw moves toward the workpiece during cutting.

Since the tip end edge of the base material 10 is formed by the curved surface 13, a larger number of abrasive grains can be secured compared with the case where the corners are angled.

Vibration is generated in the thickness direction during use of the band saw, and the load tends to be concentrated at the corner portion during cutting. The abrasive grains around the corner of the band striking according to the conventional technique with angled corners are dropped, and the cutting quality is deteriorated, and the band saw is replaced with a new band saw. Looking at the band saw to be discarded, it can be seen that the abrasive grains provided on the flat surface perpendicular to the traveling direction, that is, the flat surface of the tip portion are intact. Therefore, it is considered that the detachment of the abrasive grains around the edge determines the life of the band saw.

In the present invention, by forming the corner with the curved surface 13, a large number of abrasive grains provided on the curved surface come into contact with the workpiece. During the cutting process, the working load is dispersed into a plurality of abrasive grains so that the abrasive grains of the curved surface start dropping at about the same time as the abrasive grains provided on the flat surface 14 of the tip portion. The lifetime of the band saw can be increased correspondingly, and an excellent cutting force can be secured during the use period.

Further, as shown in the drawing, the curved surface 13 can be formed so that the curvature becomes smaller toward the tip end. As a result, a large cutting area in contact with the workpiece can be ensured and rapid cutting can be performed, and a large number of abrasive grains can be secured in the long rear portion of the curved surface 13 connected to the side surface 15.

Further, the cutting layer 30 reaches a part of the side surface 15 through the curved surface 13 of the edge. When viewed from the side, the length d2 of the cutting layer formed on the side surface may be 3.5 to 5 times the length d1 of the curved surface portion of the side exposed to the side. The cutting layer extending to the side surface has an effect of polishing the cutting surface of the workpiece to obtain an even cutting surface.

When the length d2 of the cutting layer extending to the side is less than 3.5 times, the polishing effect is not exhibited when the band saw's peripheral speed is fast. On the other hand, between 3.5 times and 5 times, the polishing effect of the cutting surface almost proportionally increases, but it is confirmed that the degree of increase of the polishing effect is remarkably decreased from 5 times. Therefore, it is preferable that the length d2 of the cutting layer extending to the side is 3.5 to 5 times the length d1 of the curved portion of the corner exposed laterally.

5 (a) is a perspective view showing a structure of a device for a groove forming step, and (b) to (d) are partial enlarged views showing various examples of grooves .

The groove forming step (s1) is to form a shallow groove (20) at the tip of the side face of the base material. To this end, the pair of forming rollers 80 on which the plurality of projections 81 of the outer circumferential surface protrude are rotated while passing the base material 10 therebetween. Grooves 20 are formed at predetermined intervals in the tip end portion of the base material 10 while being pressed by the projections 81 of the forming roller 80. [

A drive means for rotating the shaping rollers, a bracket for adjusting the spacing distance of the shaping rollers, a guider for guiding the entry position of the preform, and the like.

The height at which the grooves 20 are formed is the height at which the cutting layer (see 30 in FIG. 4 (b)) is formed. Specifically, the grooves 20 are used to firmly fix the abrasive grains.

The details of the grooves placed in the grooves are almost certainly fixed. Accordingly, it is possible to obtain a band saw in which the abrasive grains are spaced apart by at least the interval of the grooves.

Referring to FIG. 6 (b), the depth d of the groove 20 is related to the diameter of the abrasive grains 40 to be used. The depth d of the groove is formed to be smaller than the average diameter R of the abrasive grains. Therefore, when the abrasive grain enters the groove, the abrasive grain protrudes more than the side surface of the base material.

More specifically, the depth d of the groove 20 can be 20% to 50% of the average diameter r of the abrasive grains 40. The abrasive grains that have entered the grooves are exposed in the grooves at least more than half, thereby surely obtaining the indentation effect described later. The cutting effect can be increased by appropriately adjusting the degree of abrasive exposure.

In Fig. 5 (b), straight grooves 20 are shown. On the other hand, (c) shows a quadrangular groove 20 and (d) shows a staggered quadrilateral (or V-shaped) groove 20. (Fig. 5 (b)) or the staggered quadrangular groove (Fig. 5 (c)) relative to the vertical straight groove (Fig. 5 (a)) makes it possible to fix more abrasive grains. In addition, the quadrangular groove 20 has a sufficiently large abrasive grain, and when the circumference of the band saw is slow, abrasive grains provided in the grooves can be sequentially brought into contact with the workpiece, thereby enabling stable cutting of the workpiece having brittleness .

Fig. 6 (a) relates to a method for planarizing the periphery of the groove 20 after the groove forming step s1. As the groove 20 is pressed in, the peripheral portion of the groove is plastically deformed and bulged. The periphery of the groove 20 protruding from the side surface of the base material 10 adversely affects the adherence of the abrasive grains to the grooves in the subsequent implantation of the abrasive grains. Therefore, the periphery of the protruded groove is polished flat to the side surface (see Fig. 6 (b)). A polishing abrasive roll 90 may be used for polishing the periphery of the groove. A plurality of polishing abrasive rolls 90 may be provided behind the forming rollers 80 in Fig. 5 (a).

6 (b) and 6 (c) relate to the abrasive adhering step s2 and the masking step s3.

The abrasive grains (40) are mixed with the binder (50) and then adhered to the front end portion of the base material. Here, the binder 50 is a urethane-based or polyethylene-based adhesive, and is not intended to completely fix the abrasive grains on the surface of the base material but to prevent the abrasive grains from falling off from the base material in the masking step (s3) Is used. As a binder for temporarily fixing the abrasive grains, a spray type adhesive sprayed on the base material may be used.

6C, part of the abrasive grains 40 are contained in the grooves 20, and the rest are attached by the binder 50 on the surface between the grooves.

The masking step s3 is a step of attaching the masking tape 60 onto the abrasive grains. The masking tape 60 has a somewhat elasticity and is substantially the same as a commonly used article.

7 (d) shows the state after the abrasion and press-fitting step (s4). The pressing roller 99 passes over the masking tape 60 covering the base material 10 to press the abrasive grains. 7, the binder 50 is not shown. The binder is gradually removed during the process after the first electrodeposition step described later.

During the process of being pressed by the pressure roller 99, the masking tape 60 expands and contracts to grip between the abrasive grains and fills the space between the surface of the base material 10 and the abrasive grains 40.

The pressing force by the pressing roller 99 is also transmitted to the abrasive grains 40 so that the abrasive grains 40 are partially peeled off. During this process, the height of the abrasive grains 40 protruding from the surface of the base material 10 is relatively uniform. That is, the abrasive grains 40 having a large volume penetrate the base material 10 relatively more than the abrasive grains 40 having a small volume.

This has the effect of evenly adjusting the protrusion height of the abrasive grains of a band saw completed later. Generally, electrodeposited diamond or electrodeposited CBN abrasive has poor surface roughness. However, in the present invention, surface roughness is remarkably improved while being subjected to abrasive graining step.

The abrasive grains 40 located in the grooves 20 are also pressed into the grooves 20. The abrasives contained in the grooves have a relatively smaller pressing force due to the depth of the grooves than the abrasive grains on the surfaces between the grooves, but there still exists a phenomenon in which a part of the abrasive grains are pushed into the base material by the pressing force.

7 (e) shows the state after the first electrodeposition step (s5).

The primary electrodeposition step s5 is a step of press-fitting a part of the abrasive grains 40 into the base material 10 and then carrying out electrodeposition coating with the masking tape 60 attached to fasten the abrasive grains 40 to the base material . Here, details of the electrodeposition coating are the same as those generally used, and thus the description thereof will be omitted.

Since the masking tape is pressed by the pressure roller and covers the surface of the base material and the chip, there is an effect of covering the area during electrodeposition coating. Since the masking tape does not cover the entirety of the groove 20 formed in the base material, the plating liquid flows in the gap between the inner wall surface of the groove 20 and the abrasive grains 40, (B is a nickel bond).

Here, the simple fastening is intended not to fix the abrasive grains 40 located in the grooves 20 very firmly, but to secure a fixing force at a level that prevents the abrasive grains 40 from being easily separated. Specifically, although the fastening is not at a level of firmly fixing the abrasive grains so that the abrasive grains can be used immediately after being attached to the sawing apparatus, the abrasive grains of the abrasive grains It is called fixing force.

However, if the depth of the groove is made deeper to secure a sufficient space for the plating liquid to flow in, a strong fixing force enough to use the band saw immediately after the first electrodeposition step can be secured.

7 (f) relates to a masking removing step (s6) for removing the masking tape.

The part of the abrasive grains 40 is removed together with the masking tape 60 and the remaining abrasive grains 40 are left on the base material 10 when the masking tape 60 is peeled off after the first electrodeposition step s5.

At this time, most of the abrasive grains 40 that enter the grooves 20 and are fixed by electroplating are left in the base material 10.

Even if all of the abrasive grains existing on the surface of the base material between the grooves are removed together with the masking tape, the abrasive grains located at least in the grooves are still present in the base material, so that a band saw having abrasive grains can be obtained.

On the other hand, the abrasive grains 40 located on the surface of the base material between the grooves 20 are not adhered to the masking tape 60 depending on conditions such as depth and shape angle, distribution and hardness of the binder, It still sticks to the base material 10. Usually, large diameter abrasive grains remain in the base material, and small diameter abrasive grains tend to be removed along with the masking tape, but this is not necessarily the case.

Various shapes of concave grooves 16 are formed on the surface of the base material 10 while the abrasive grains 40 partially embedded in the base material 10 are separated.

Fig. 8 relates to the secondary electrodeposition step (s7).

The degree of exposure of the abrasive grains 40 is controlled by controlling the plating thickness while firmly fixing the remaining abrasive grains 40 by electrodeposition plating after removing the masking tape 60 to the base material 10.

A plurality of irregular grooves 31 are formed on the surface of the cutting layer 30 completed by the second electrodeposition plating in accordance with the concave groove 16 formed by the abrasion of the abrasive grains. The grooves 31 act like the pores of the grinding wheel, and serve to accommodate the grinding chip during the cutting operation, to prevent overheating of the band saw and workpiece.

(S8) after the second electrodeposition step, followed by a further heat treatment step. The heat treatment is performed at a temperature of 230 to 260 占 폚 for 23 to 27 minutes, and is gradually cooled at room temperature. The additional heat treatment greatly increases the elasticity of the band saw.

According to a comparative experiment with and without additional heat treatment, it was confirmed that the hardness of the Rockwell was improved to 120 to 150 by heat treatment under the above conditions. However, when the heating time is less than 230 ° C, the variation of the Rockwell hardness is less than 100 even if the heating time is varied from 10 minutes to 50 minutes. When the temperature exceeds 260 ° C, the surface of the band saw is blackened, The problem began to arise and the merchantability started to deteriorate.

Thus, it was concluded that additional heat treatment would be required for 23 to 27 minutes at a temperature ranging from 230 ° C to 260 ° C, which is a range in which soot does not form on the surface while a large increase in Rockwell hardness is observed.

According to the embodiment of the present invention, the abrasive grains formed by the electrodeposition plating are fixed and the abrasive grains are pressed into the grooves of the base material, so that the abrasive grains arranged in the grooves arranged at regular intervals can exhibit their functions without dropping out for a long time. In addition, the joint of the loop is not projected, and the surface roughness of the cutting layer is improved, so that the quality of the cutting surface of the workpiece is improved. It also minimizes the loss of workpieces and is suitable for cutting expensive workpieces.

100: Band saw
10: base metal
11: both ends 12: welding spot 13: curved surface 14: flat surface
15: side 16: concave groove
20: groove 30: cutting layer 31: groove 40: abrasive grain
50: binder 60: masking tape
70: polishing roller 71: molding groove
80: forming roller 81: projection
90: abrasive roll 99: pressure roller

Claims (4)

A groove forming step of pressing the front end of the side face of the base material, which is loop-shaped,
A temporary abrasive adhering step of adhering an abrasive grain mixed with a binder to a front end portion of the base material on which the groove is formed,
A masking step of attaching a masking tape to the front end portion of the base material so as to cover the adhered abrasive grains,
An abrasive-pressing step of pressing a portion of the abrasive grains on the base material by pressing on the masking tape with a pressure roller and evenly heightening the abrasive grains protruded from the surface of the base material,
A first electrodepositing step of electrodepositioning the abrasive grains after the abrasive graining step and attaching the masking tape to the abrasive grains,
A masking removing step of removing the masking tape to remove a part of the abrasive grains which have been pressed into the base material,
And a second electrodepositing step of forming a plurality of irregular grooves by the concave grooves on the surface of the base material while electrodepositing the front end of the base material to fix the abrasive grains. delete The method of claim 1,
After the secondary electrodeposition step
And a post-treatment step of heat-treating at 230 to 260 DEG C for 23 to 27 minutes. 4. A device according to any one of claims 1 to 3,
The abrasive grains are firmly attached to the grooves of the groove forming step,
Wherein a plurality of irregular grooves are formed on the surface of the base material by the clearance of abrasive grains detached from the surface of the base material through the masking removing step.

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