JP2007061939A - Wire saw - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wire saw which has an excellent grinding ability and an improved service life by preventing eccentric wear of beads and making effective use of a grinding surface of each bead. <P>SOLUTION: According to the structure of the wire saw, a number of cylindrical beads 3 are fixed to a wire, and a polygonal beads 4 having a polygonal cross section are arranged at every arbitrary number of the cylindrical beads 3. Elliptic beads 5 having an elliptic cross section may be arranged in place of the polygonal beads 4, or the polygonal beads 4 and the elliptic beads 5 may be mixedly arranged. Each elliptic bead 5 has hard layers 10 in respective major axis regions of an ellipse of an abrasive grain layer 8. On the other hand each polygonal bead 4 has the hard layers 10 in respective angular regions of an abrasive grain layer 9. The hard layer 10 may be formed by hardening a binder of each of the abrasive grain layers 8, 9, or alternatively by increasing the concentration compared with that of the other region of each of the abrasive grain layers 8, 9. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a wire saw that is used when cutting stone, concrete, building materials, and the like.

  When cutting stone, concrete, building materials, or the like, a wire saw is used in which a large number of cylindrical beads, to which abrasive grains are fixed, are connected to a steel wire in a rosary shape. Such a wire saw is used for cutting the above-mentioned work material by connecting the ends of the wire into an endless shape and applying a tension to drive the pulley.

An example of a conventional wire saw is shown in FIG. 6A is an overall view of the wire saw, FIG. 6B is a partially enlarged view thereof, and FIG. 6C is a cross-sectional view taken along line AA of FIG. 6B.
In the conventional wire saw 51, a large number of cylindrical beads 53 are fixed to the wire 52, and the wire 52 is covered with rubber. The cylindrical beads 53 are formed by providing an abrasive layer 55 on the outer periphery of the bead base 54.

  As shown in FIG. 7A, the wire saw 51 is used for cutting the work material 60 by twisting and connecting the ends of the wires 52. By twisting at this time or by handling the guide pulley, these cylindrical beads 53 rotate so that only a specific surface of the cylindrical beads 53 is worn as shown in FIG. 7B. I am trying not to.

However, the rotation of the cylindrical beads 53 depends on conditions such as wire feed speed, wire tension, work material condition, work material reinforcement (rebar thickness, rebar arrangement pitch, etc.), aggregate material, and the like. If it is not sufficiently performed, as shown in FIG. 7C, uneven wear occurs in which only the portion indicated by the oblique lines is worn. When such uneven wear occurs, the life is reduced because the unused abrasive grain layer remains and the life is shortened.
A wire saw for preventing uneven wear of beads is described in Patent Document 1.

Japanese Patent Laid-Open No. 11-156635

  This wire saw is intended to suppress uneven wear of beads by placing beads using superabrasive grains having a larger particle size between the superabrasive beads, but once caused uneven wear. Since the beads further wear on the contact surface with the work material, uneven wear cannot be sufficiently suppressed.

  The present invention has been made in order to solve the above problems, and prevents uneven wear of beads, has an excellent grinding ability by effectively utilizing the grinding surface of beads, and improves the life. The object is to provide a possible wire saw.

  In order to solve the above-described problems, the present invention provides a cylindrical bead having a circular cross-section formed by fixing abrasive grains on the surface of a cylindrical base metal and arranged at intervals in the longitudinal direction of the wire. Each time an arbitrary number of the cylindrical beads are arranged, elliptical beads having an elliptical cross section or polygonal beads having a polygonal cross section are arranged, and the elliptical beads or the polygonal beads have a phase angle with each other. Arranged differently, a hard layer having higher wear resistance than the other part of the abrasive grain layer is provided in the long axis side area of the abrasive grain layer of the elliptical bead or the corner side area of the polygonal bead. It is a wire saw characterized by this.

By arranging the elliptical beads or polygonal beads, rotation of the cylindrical beads is promoted and uneven wear is suppressed. In addition, the long axis region of the abrasive layer of the elliptical beads or the polygonal beads are used. Since the hard layer is provided in the corner-side regions, the wear resistance in these regions increases, so even if elliptical beads or polygonal beads are ground repeatedly, the shape approaches that of cylindrical beads Can be prevented. Therefore, the rotation of the beads is continued forever and the life is improved.
The hard layer can be formed by curing the binder of the abrasive layer, or can be formed with a higher concentration than other parts of the abrasive layer.

  Since the present invention can prevent uneven wear of beads, it is possible to realize a wire saw that has an excellent grinding ability by effectively utilizing the grinding surface of beads and can improve the service life.

Below, the wire saw of this invention is demonstrated based on the embodiment.
FIG. 1 shows a wire saw according to an embodiment of the present invention.
In the wire saw 1, a large number of cylindrical beads 3 are fixed to the wire 2, and each time an arbitrary number of cylindrical beads 3 are arranged, polygonal beads 4 having a polygonal cross section are arranged. Instead of the polygonal beads 4, elliptical beads having an elliptical cross section may be arranged, or the polygonal beads 4 and the elliptical beads may be mixed and arranged. The wire 2 is covered with rubber.

FIG. 2 shows the structure of cylindrical beads, elliptical beads, and polygonal beads.
A cylindrical bead 3 shown in FIG. 2A is formed by providing an abrasive grain layer 7 having a circular cross-sectional outer shape on the outer periphery of a bead base 6. An elliptical bead 5 shown in FIG. 2B is formed by providing an abrasive grain layer 8 having an elliptical cross-sectional outer shape on the outer periphery of a bead base 6. The polygonal bead 4 shown in FIG. 2C is formed by providing an abrasive layer 9 having a polygonal cross-sectional outer shape on the outer periphery of the bead base 6.

  In the elliptical bead 5 shown in FIG. 2 (b), the hard layer 10 is radially provided from the center side to the outer peripheral side in the elliptical long-axis region of the abrasive grain layer 8. Further, in the polygonal bead 4 shown in FIG. 2C, the hard layer 10 is radially provided from the center side to the outer peripheral side in the corner region of the abrasive grain layer 9. The hard layer 10 may be a hardened binder of the abrasive layers 8 and 9 or may have a higher degree of concentration than other portions of the abrasive layers 8 and 9. .

  The elliptical beads 5 or the polygonal beads 4 are arranged so that the phase angles are different from each other. Here, the phase angle being different means that the major axis direction of the elliptical bead 5 or the direction of the corners of the polygonal bead 4 is not the same direction, but are different from each other. When the elliptical beads 5 or the polygonal beads 4 are arranged in this way, the rotation of these beads is easily performed.

Next, operation | movement of the wire saw of this invention is demonstrated using FIG.
Here, the case where the polygonal bead 4 is used is shown, and when the polygonal bead 4 comes into contact with the work material 20 as shown in FIG. The cutting force 21 to the work material 20 due to the wire tension acts, and the reaction force 22 acts on the polygon bead 4 from the work material 20 at the contact point 23 between the polygon bead 4 and the work material 20. To do.
As shown in FIG. 3B, a twisting moment 24 acts on the polygonal bead 4 so that the polygonal bead 4 rotates, and as shown in FIG. The contact position changes.

  As described above, since the polygonal beads 4 are rotated by arranging the polygonal beads 4, and then the rotation of the cylindrical beads 3 that are in contact with the work material 20 is promoted, uneven wear of the beads can be prevented. it can. However, as the polygonal beads 4 are also ground, the corner-side region is worn and approaches the cylindrical beads as shown in FIG. In consideration of this point, in the wire saw of the present invention, as shown in FIG. 5, the hard layer 10 is provided in the corner region of the abrasive layer 9, thereby reducing the wear of the corner region, Even if grinding is repeated, the polygonal beads 4 continue to maintain the polygonal shape. For this reason, the rotation of the beads is continued indefinitely, and the life is improved.

  The above description is for the case where the polygonal bead 4 is used, but the same applies to the case where the elliptical bead 5 is used. In the case of the elliptical bead 5, the elliptical long axis region of the abrasive layer 8 is hard. By providing the layer 10, there is little wear on the long axis side region, and the elliptical beads 5 continue to maintain the elliptical shape even after repeated grinding. For this reason, the rotation of the beads is continued indefinitely, and the life is improved.

Specific test examples are shown below.
As an example of the wire saw having the structure shown in FIG. 1, each time an arbitrary number of cylindrical beads 3 are arranged, a wire saw in which elliptical beads 5 having an elliptical cross section are prepared, and a cutting test is performed. Table 1 shows the specifications of the superabrasive layer of the produced wire saw. Here, the hard layer is formed by increasing the degree of concentration from the other part of the abrasive layer.

In Table 1, the thickness of the hard layer of the inventive elliptical bead 5 is 1.2 mm, which is three times the average grain size of the abrasive grains.
For the above wire saw, as shown in FIG. 8, the maximum value D and the minimum value d of the outer diameter of the cylindrical and elliptical beads in use are measured, and the aspect ratio (d / D × 100) is determined. Asked.
Table 2 shows the test conditions.

  The test results are shown in FIG. No. 1 shows the result about the wire saw comprised only by the cylindrical bead 3. FIG. This wire saw had a low rotation effect, and the cylindrical beads 3 after the test had a partial wear and the aspect ratio became 75%.

  Next, no. 2-1. 2-2 is a wire saw composed of cylindrical beads 3 and elliptical beads 5 that do not have the hard layer 10, and the number of the elliptical beads 5 is arranged in the range of 2 to 6 per 1 m for this wire saw. The result about five wire saws is shown. No. 2-1, the aspect ratio of the cylindrical beads 3 The aspect ratio of the elliptical bead 5 not having the hard layer 10 is shown in 2-2. By arranging the elliptical beads 5, the aspect ratio of the cylindrical beads 3 is no. No. 1 to 75%. As shown by 2-1, it is improved to 80% to 95%. Further, when the arrangement of the elliptical beads 5 is increased from 2 / m to 5 / m, the improvement is from 80% to 95%.

  Next, no. 3-1. 3-2 is a wire saw constituted by the cylindrical beads 3 and the elliptical beads 5 provided with the hard layer 10 of the present invention, and the number of the elliptical beads 5 is 2 to 6 per 1 m for this wire saw. The result about five wire saws when arranged in a range is shown. No. 3-1, the aspect ratio of the cylindrical beads 3 The aspect ratio of the elliptical bead 5 provided with the hard layer 10 is shown in 3-2. By arranging the elliptical beads 5 provided with the hard layer 10, the aspect ratio of the cylindrical beads 3 is No. 1. From the aspect ratio of 75% of the cylindrical beads 3 shown in FIG. As shown by 3-1, it is improved to 85% to 100%. Further, when the arrangement of the elliptical beads 5 is increased from 2 pieces / m to 5 pieces / m, it is improved from 85% to 100%.

Here, no. In the wire saw in which the elliptical beads 5 having the hard layer 10 of the present invention shown by 3-2 are arranged, the aspect ratio of the elliptical beads 5 is such that the number of the elliptical beads 5 is 2 / m to 5 / m. When changed, it is 75% to 72%. On the other hand, no. In the wire saw in which the elliptical beads 5 having no hard layer 10 shown in 2-2 are arranged, the aspect ratio of the elliptical beads 5 is changed from 2 / m to 5 / m. In some cases, it is 80% to 77%, and the shape approaches the cylindrical beads 3.
From this result, the elliptical bead 5 having the hard layer 10 maintains an elliptical shape as compared with the elliptical bead 5 not having the hard layer 10.

  Also, in the wire saw in which the cylindrical beads 3 and the elliptical beads 5 having an elliptical cross section are arranged every time seven cylindrical beads 3 are arranged, the concentration of the cylindrical beads 3 and the elliptical beads 5 is the same. Then, the wire saw in which the binder of the elliptical beads 5 is hardened to form a hard layer, the cylindrical beads 3, and the polygonal beads 4 having a hexagonal cross section each time seven cylindrical beads 3 are arranged. In the arranged wire saw, a wire saw in which the binder of the polygonal beads 4 was cured to form a hard layer was manufactured and tested. The result is shown in FIG. Even when the hard material is formed by curing the binder, the same effect as that obtained when the hard layer is formed by increasing the degree of concentration is obtained.

  Since the present invention can prevent uneven wear of the beads, it can be used as a wire saw that has an excellent grinding ability by effectively utilizing the grinding surface of the beads and can improve the service life.

It is a figure which shows the wire saw which concerns on embodiment of this invention. It is a figure which shows the structure of a cylindrical bead, an elliptical bead, and a polygon bead. It is a figure which shows operation | movement of the wire saw which concerns on embodiment of this invention. It is a figure which shows the mode of abrasion of the conventional polygon bead. It is a figure which shows the mode of abrasion of the polygon bead by which the hard layer was provided in the area | region of the corner | angular side of an abrasive grain layer. It is a figure which shows an example of the conventional wire saw. It is a figure which shows the mode of grinding using the conventional wire saw. It is a figure which shows the shape of the column-shaped bead and the elliptical bead in use. It is a figure which shows a test result. It is a figure which shows a test result.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wire saw 2 Wire 3 Cylindrical bead 4 Polygonal bead 5 Elliptical bead 6 Bead base metal 7, 8, 9 Abrasive layer 10 Hard layer 20 Work material 21 Cutting force 22 Reaction force 23 Contact point 24 Torsional moment

Claims (3)

  Each time cylindrical beads having a circular cross section formed by adhering abrasive grains to the surface of a cylindrical base metal are arranged at intervals in the longitudinal direction of the wire, and any number of the cylindrical beads are arranged. In addition, elliptical beads having an elliptical cross section or polygonal beads having a polygonal cross section are disposed, and the elliptical beads or the polygonal beads are disposed such that the phase angles thereof are different from each other. A wire saw characterized in that a hard layer having higher wear resistance than other portions of the abrasive grain layer is provided in a long axis side region of the layer or a corner side region of the polygonal bead.   The wire saw according to claim 1, wherein the hard layer is a hardened binder of an abrasive layer.   The wire saw according to claim 1, wherein the hard layer has a higher degree of concentration than other portions of the abrasive layer.

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