JP4419191B2 - Fiber cutting blade and cutting apparatus having the same - Google Patents

Description

  The present invention relates to a fiber cutting blade used in a glass fiber manufacturing process and a cutting apparatus including the fiber cutting blade.

  Glass fiber products are made by melting various inorganic glass raw materials to a high temperature to a homogeneous state, drawing the glass from a plurality of nozzles provided at the bottom of the platinum bushing, spinning it as a continuous monofilament, and rapidly using water spray. It is cooled and further coated with a sizing agent to form hundreds to thousands of strands to form strands, which are wound with a winder to form a roasted yarn called a cake, which is used for various applications. ing.

  The glass chopped strand can be obtained by releasing the strand from the cake, aligning the strands, and continuously cutting the strand into a predetermined length by a cutting device such as a roving cutter. The chopped strands are supplied to a dispersing device and processed into chopped strand mats, papers, tapes, or the like, or FRTP (Fiberglass Reinforced Thermoplastics), FRP (Fiberglass Reinforced Plastics), GRC (Glassfibre Reinforced Materials, etc.) Alternatively, it is also used as a filler, additive, reinforcing material, reinforcing agent, etc.) and is packed into a product in an integrated state.

Since a cutting blade for cutting glass fibers such as cake into glass chopped strands is an important member for obtaining glass chopped strands having stable quality, various improvements have been made so far. For example, Patent Document 1 devises a rubber roll made of a composite material in order to increase the strength of the rubber roll pressed against the cutting blade. Patent Document 2 discloses an invention in which the wear of the blade is reduced by limiting the ratio of the Vickers hardness of the blade portion 1 and the base portion 2 and the blade portion 1 can be used for a long time. Moreover, in patent document 3, the breakage | damage of a blade is suppressed by limiting the ratio of the blade part length of a fiber cutting blade comprised by joining via the joining layer 3 of the blade part 1 and the base | substrate part 2, and base | substrate part length. An invention that can be performed is disclosed. Further, Patent Document 4 discloses an invention about a structure that relieves residual strain due to welding of the blade portion 1 and the base portion 2. In patent document 5, the Vickers hardness of the blade part 1 is further improved to 2000 or more, and in patent document 6, the invention of the base part 2 that facilitates joining with the blade part 1 having high hardness is disclosed.
Japanese Utility Model Publication No. 05-96033 JP 2002-355788 A JP 2002-361590 A JP 2002-370192 A JP 2003-53693 A JP 2003-266370 A

  However, the improvement of the cutting blade that has been performed so far is not sufficient. As the cutting blade, a single-edged blade is generally used whose blade edge shape is inclined on only one side of its cross section. And since the shape of such a single-edged cutting blade is not symmetrical with respect to the thickness direction, if residual stress is generated by heating when welding the blade part and the base part, the blade edge part or the bottom part will be distorted. There's a problem. In order to eliminate this distortion, it is necessary to perform polishing while adjusting the bottom of the blade. However, it may be difficult even for a skilled worker to polish the blade edge evenly, and the generated distortion of the blade portion is 0.35 mm at the position where the blade distortion amount at the center portion of the blade is maximized. As a result, the service life of the blade was shortened.

  In view of such a situation, the present inventors provide a fiber cutting blade capable of realizing a stable cutting process for a long time in the cutting of glass fiber, and a glass fiber cutting device provided with the fiber cutting blade. This is the issue.

The fiber cutting blade of the present invention is a fiber cutting blade to which a blade portion for cutting glass fibers and a base portion are fixed , wherein the base portion is made of carbon tool steel, and the cutting edge of the blade portion has a double-edged shape, The apex angle γ is divided by a blade axis that is a straight line connecting the apex angles of the two blades and the equally dividing point of the blade bottom side length in a cross section perpendicular to the blade width. The relationship of | α−β | ÷ γ ≦ 0.10 is established, where α is one of the two blade edge section inclination angles and β is the other.

  Here, it is a fiber cutting blade that cuts glass fiber, and the cutting edge of the blade part is a double-edged shape means that the cutting blade is cut into a short fiber such as a glass chopped strand by cutting glass fiber or inorganic glass. Looking at the cross-sectional direction of the blade whose shape is 90 ° with respect to the width of the blade, it has an inclined portion, that is, a tapered portion on both sides of the blade, and looks like two conventionally used single blades are bonded together. It means a double-edged shape or a double-edged shape.

  Further, the apex angle γ is divided by a blade axis line that is a straight line connecting the apex angle of the both blades and the equally divided point of the blade bottom side length in a cross section perpendicular to the blade width, where γ is the apex angle of the both blades. When one of the two blade tip cross-sectional inclination angles is α and the other is β, the relationship | α−β | ÷ γ ≦ 0.10 is established. A connecting line segment between an apex of the blade and an internal dividing point that divides the length of the bottom side of the blade into two equal parts (for convenience, a virtual “axis” is referred to as a “blade axis line”. The term “line” is used to describe in a plane, but because it is originally a three-dimensional shape, the “axis” is a “plane” perpendicular to the page, and the “line” is also “plane”. However, for these two expressions, such expressions are also used for the sake of convenience). Is expressed as α and β, respectively, and the value obtained by dividing the absolute value of the difference between α and β by γ, which is the sum of both inclination angles, is 0.10, that is, a ratio of 10% or less. ing.

  Here, the inclination angle can be defined as follows. The inclination angle will be described with reference to the conceptual diagram shown in FIG. This figure schematically shows only a part of the cross section of the inclined surface on one side of both blades. Here, P is the apex of the blade edge, R is the end point of the blade inclined portion, Z is on the blade axis, the intersection of the perpendicular line dropped from R onto the blade axis, and the blade axis, La is the dimension from P to Z The dimension parallel to the blade axis of one blade edge inclined portion of both blades, Ja represents the inclined portion length, and Wa represents the dimension from R to Z. The one-side inclination angle α is the length on one side parallel to the blade axis from the blade tip P corresponding to the one-side blade inclined portion (this length is referred to as the one-side cutting edge dimension). La is the base, and the position from the apex to the cutting edge dimension on one side of the blade axis, that is, the point perpendicular to the blade axis intersects with the inclined part on one side, that is, the dimension Wa to R is increased. This is the angle that can be calculated as the arc tangent of the trigonometric function for the triangle formed. In the figure, it is an acute angle formed by the RP line segment and the PZ line segment. Therefore, the angle of inclination on the other side is also the same as the length of one side parallel to the blade axis from the tip of the blade corresponding to the blade edge inclined portion on the other side (this length is called the cutting edge dimension on one side). And the triangle formed with the distance from the position from the apex to the cutting edge dimension on the other side of the blade axis to the line perpendicular to the blade axis intersecting the inclined part on the other side is the triangle. An angle that can be calculated as the arc tangent of a function. Therefore, the double-edged angle value is an angle that can be expressed as the sum of the inclination angle on one side and the inclination angle on the other side.

  In addition, the cross-sectional shape of the inclined portion of the cutting edge, that is, the tapered portion is not necessarily a straight line. That is, even if the cross-sectional shape of the taper portion is a curve, there is no problem, and the taper portion may be convex outward with respect to the blade axis or may be concave outward with respect to the blade axis. And about the taper part of the cutting edge of one side, a curvature radius should just be larger than the circular arc drawn by using the cutting edge dimension from the blade edge vertex corresponding to the cutting edge inclination part of one side as a curvature radius. Similarly, on the other side, the radius of curvature only needs to be larger than an arc drawn with the cutting edge dimension from the tip of the cutting edge corresponding to the inclined portion of the cutting edge on the other side as the curvature radius.

  If both the one side taper part and the other side taper part are convex outward with respect to the blade axis, they are distinguished from each other by calling it a clam-type blade or convex grind, similar to the name of a knife or knife. When the other side tapered portion is also concave outward with respect to the blade axis, it is classified as an inner / outer R shape or a hollow grind. Furthermore, when the taper portion is linear, it is referred to as straight grind.

  Convex grinds and hollow grinds both have their merits and demerits, so neither can be determined to be optimal. Therefore, it is possible to select after considering various factors such as the use conditions, the size of the fiber to be cut, the cross-sectional shape of the fiber and the material of the fiber. In addition, by making the shape close to straight grind, the blade polishing operation itself becomes easier than other shapes, so when considering this point as the first, it is preferable to make the shape close to straight grind. is there.

  In addition, from the viewpoint of symmetry of the blade edge cross section, the vertical angle of the both blades is γ, and in a cross section perpendicular to the blade width, a straight line (blade axis line) that connects the vertex of the blade edges and the equally divided point of the blade bottom side length. It is preferable that the relationship | α−β | ÷ γ ≦ 0.10 is satisfied, where α is one of the two blade edge section inclination angles obtained by dividing the apex angle γ and β is the other. More preferably, the ratio is 0.08 or less, even more preferably the ratio is 0.07 or less, even more preferably the ratio is 0.06 or less, and most preferably The ratio is 0.058 or less.

  In addition, regarding the inclination angle of the cutting edge, for example, in the step of cutting into glass chopped strands, the cutting edge has a cutting edge having a shape close to a symmetric shape. Since the stress value applied to the taper is close, there will be no bias in the wear of the cutting blade caused by the use of the cutting blade over time, and stable glass cutting quality will be maintained for a long time. It is because it becomes possible to continue doing.

  In addition to the convex cross-section shape of convex grind, hollow grind, and straight grind, the shape where one side taper part is convex outward with respect to the blade axis and the other side taper part is concave with respect to the blade axis is also polished. Can do. However, such a shape does not only increase the residual distortion during welding by making the cross-sectional shape of the blade deviate from the symmetrical shape, but also from the viewpoint of durability of the blade edge. This is not preferable because the risk of the strength being weakened increases.

  In the case of adopting the curved shape of the convex grind or hollow grind from the above viewpoint, the ratio of the curvature radius of the taper on the other side to the curvature radius of the taper on the one side is 0.7 or more, more preferably 0.8 or more, and still more preferably 0.9 or more.

  Further, on one side or the other side, a shape in which curved lines in which one tapered portion has a plurality of curvature radii of two or more may be combined. However, even in this case, the curvature radii of the tapered portions on one side and the other side are preferably 0.7 or more with respect to the curvature radius value on the other side as described above. And it is preferable that the taper part shape of one side is as close as possible to the symmetrical shape which made the other side taper part shape symmetrical with the blade axis.

  In addition to the above, the fiber cutting blade of the present invention has a dimension parallel to the blade axis of one of the blade tip inclined portions of both blades in addition to La and a dimension parallel to the blade axis of the other blade tip inclined portion and equal to La or When the small dimension is Lb, a relationship of (La−Lb) ÷ La ≦ 0.40 is established.

  Here, when La is a dimension parallel to the blade axis of one blade edge inclined portion of both blades, and Lb is a dimension parallel to the blade axis of the other blade edge inclined portion and equal to or smaller than La, (La -Lb) ÷ La ≦ 0.40 is satisfied, in addition to the above-described condition regarding the apex angle at the tip of the blade tip, the blade shape is observed from the cross-sectional direction as close as possible to a symmetrical state. The axial length (cutting edge dimension) of the inclined portion of the blade edge is preferably as close to the same length as possible on the left and right with respect to the apex. The axial length of the part is one side with the larger cutting edge dimension (La: called the cutting edge dimension on one side) and the other dimension with the smaller cutting edge dimension in the blade axial direction from one side (Lb: the other side Cutting on one side against the difference between the cutting edge dimensions) Ratio for the dimensions of 0.40, that is intended to be achieved by a 40% or less.

  From the above viewpoint, the value of (La−Lb) ÷ La is more preferably 0.38 or less, still more preferably 0.37 or less, still more preferably 0.36 or less, and most preferably. Is 0.35 or less.

The material constituting the fiber cutting blade of the present invention may be any material as long as it achieves desired strength and hardness and is excellent in abrasiveness. In particular, it is preferable to employ an alloy of a system containing tungsten carbide as a material preferably employed as the fiber cutting blade of the present invention. These alloys have properties such that the coefficient of thermal expansion in the temperature range of 25 ° C. to 200 ° C. is 48 to 62 × 10 ⁻⁷ / K.

  Moreover, in the fiber cutting blade of the present invention, in addition to the above, the material of the blade portion is preferably made of cemented carbide.

  Here, the material of the blade portion is made of cemented carbide means that it is made of an extremely hard alloy obtained by sintering a metal element carbide and a metal. Specifically, WC-Co, WC-TaC-Co, WC-TiC-Co, and WC-TiC-TaC-Co cemented carbides can be used. Further, as an example of the cemented carbide used in the present invention, it is obtained by sintering fine particles of tungsten carbide containing 9.5% by mass or less of cobalt as a binder, for example, 92% by mass of tungsten carbide powder. And 8% by mass of cobalt powder, fired, and then processed by HIP (Hot Isostatics Press) to finish to a predetermined size and shape. The cemented carbide thus obtained has a Vickers hardness of Hv. 1800 or more.

  In addition to the above, the fiber cutting blade of the present invention may have a blade portion fixed to a base portion of carbon tool steel.

  Here, that the blade portion is fixed to the base portion of the carbon tool steel means that the blade portion made of cemented carbide and the base portion made of carbon tool steel subjected to quenching and tempering are fixed by some means. It means that.

  The blade part and the base part may be bonded to each other as long as a sufficiently high strength and a stable function can be realized. Also, the best method can be adopted by appropriately selecting various methods for welding methods, materials, instruments, and the like. That is, it may be direct welding or bonding via a low melting point metal foil or the like.

  With such a configuration, for example, when the fiber cutting blade of the present invention is attached to a cutter roller and used, even if the cutter roller is rotated at a high speed, the base portion sufficiently absorbs vibration applied to the blade edge. Is less likely to break, and the productivity of glass chopped strands can be greatly improved.

In addition to the above, the fiber cutting blade of the present invention is joined by bonding a bonding material foil having a thickness of 0.05 to 0.9 mm between the end surface of the blade portion and the end surface of the base portion. The Vickers hardness is a value that is 1.0 to 5.5 times the Vickers hardness of the base portion.

  In addition, with respect to the fiber cutting blade of the present invention, the amount of strain generated by welding can be measured by using a jig or measuring instrument to which a micro gauge, a laser measuring device, a stylus measuring device or the like is fixed. Is possible. Therefore, in order to realize the present invention, the shape of the fiber cutting blade of the present invention is obtained by adjusting the shape of the blade edge while measuring the processing strain and thermal strain after the polishing and welding of the fiber cutting blade. Thus, it can be processed and molded.

The glass fiber cutting device of the present invention includes a rubber roll pressed against the cutter roll and a cutter roll provided with a plurality of cutting blades, and the cutting blades are sequentially pressed against predetermined positions of the glass strands so that the two rolls are in contact with each other. A glass chopped strand having a desired size is obtained by cutting glass strands that are continuously supplied, and the chopped strands after being cut are collected at the bottom or side of the cutting mechanism having a cutting blade. It is a glass fiber cutting device, Comprising: The said cutter roll comprised the fiber cutting blade demonstrated in the above-mentioned paragraph, It was characterized by the above-mentioned.

That is, the glass fiber cutting device of the present invention includes a rubber roll that is pressed against the cutter roll and a cutter roll that is provided with a plurality of cutting blades, and the cutting blades are sequentially pressed into contact with predetermined positions of the glass strand so that two rolls are provided. A glass chopped strand having a desired size is obtained by cutting the glass strand continuously fed between them, and the chopped strand after being cut is collected at the lower part or the side part of the cutting mechanism having a cutting blade. A glass fiber cutting device having a structure having a blade shape having symmetry as described above, and the cutting blade satisfies a condition of | α−β | ÷ γ ≦ 0.10, and more preferably (La -Lb) ÷ La ≦ 0.40, blade member quality, and base member quality may be as described above.

Glass fiber cutting apparatus of the present invention, have a function which is suitable for continuous cutting of chopped strands from the strand, is disposed on a roll at regular intervals a plurality of cutting blades in order to achieve for example a continuous cut A glass chopped strand having a desired dimension can be obtained by cutting the glass strand continuously supplied between the two rolls by sequentially press-contacting the cutting blade to a predetermined portion of the glass strand. Monodea Ru. As a method of arranging such a plurality of cutting blades, for example, a cutter roll for pressure contact with the rubber roll and a rubber roll, arranged structures are contemplated a plurality of cutting blades on the cutter roller. If it is an apparatus having such a structure, the size and material of the rubber roll pressed against the cutter roll can be selected as appropriate, and a material having high heat resistance and mechanical durability can be selected efficiently. It is possible to adopt a dimension that can maintain a proper cut state. The same applies to the cutter roll, and there is no problem as long as a structure having a sufficiently high durability can be adopted.

  In addition, the rubber roll pressed against the cutter roll has sufficient strength to be practically used, so that at least one selected from glass fiber, glass flake, organic fiber, glass bead, ceramic fiber, and ceramic particles in the rubber roll. The above reinforcing filler can be contained.

  Further, in the fiber cutting device of the present invention, when the cutting blades are arranged at a short distance (for example, at intervals of 3 mm), the cutting blades may be gradually worn and damaged due to contact with each other. It is preferable to attach a cushioning material such as rubber (e.g., thickness of 0.2 to 0.5 mm), a metal spacer, or the like to both sides of the steel sheet because the cutting blade is less likely to be damaged.

  Further, the glass fiber cutting device of the present invention employs a structure for collecting chopped strands after being cut at the lower part or side part of the cutting mechanism having a cutting blade. By quickly moving the generated glass chopped strands outside the system of the cutting mechanism, it is possible to prevent the operation of the cutting mechanism from being hindered. As such a structure, for example, a belt conveyor or a conveyance duct using an air current can be employed, and a necessary one can be employed according to the scale of the facility.

  In addition, the glass fiber cutting device of the present invention can incorporate a mechanism for removing a glass chopped strand that does not satisfy a predetermined standard such as an outer shape and a length or a foreign matter mixed in the glass chopped strand as necessary. In order to realize such a mechanism, an optical measuring device such as a laser can be provided before and after the cutting mechanism.

  Furthermore, the supply mechanism for supplying the strands to the glass fiber cutting device of the present invention may also serve as the strand cutting mechanism, and the strand supply device is provided in this device separately from the strand cutting mechanism. It may be.

  (1) As described above, the fiber cutting blade of the present invention is a fiber cutting blade for cutting glass fibers, the blade edge of the blade portion has a double-edged shape, and the apex angle of the both blades is γ, and the blade width is One of the two blade edge cross-sectional inclination angles at which the apex angle γ is divided by the blade axis that is a straight line connecting the vertex of the blade edge and the equally divided point of the blade bottom side length in a vertical section is α, and the other is When β, the relationship | α−β | ÷ γ ≦ 0.10 holds, so that when the glass fiber is cut, an equal load is not applied to only one side of the blade edge. It is possible to cut the glass fiber in a state, and it is possible to realize a cutting process in which the cut surface of the fiber is arranged.

  (2) Further, the fiber cutting blade of the present invention has a dimension parallel to the blade axis of one blade edge inclined portion of both blades, La, and a dimension parallel to the blade axis of the other blade edge inclined portion, which is equal to or smaller than La. Since the relationship of (La−Lb) ÷ La ≦ 0.40 is established when the dimension to be obtained is Lb, by reducing the amount of blade distortion that occurs when welding the cutting blade, It is possible to reduce the labor of adjustment work such as polishing, and to improve the glass fiber cutting ability of the cutting blade after adjustment.

  (3) Furthermore, the fiber cutting blade of the present invention has a stable cutting function for a long time because the material of the blade portion is made of cemented carbide, and the useful life of the glass fiber cutting blade is practically used. It is long enough to be able to.

  (4) Furthermore, since the fiber cutting blade of the present invention is formed by fixing the blade portion to the base portion of the carbon tool steel, the blade portion does not enter an excessive impact force. Therefore, it is possible to reduce problems such as the blade life being unduly shortened.

  (5) Since the glass fiber cutting device of the present invention has the above-described configuration, it becomes possible to produce glass chopped strands with high efficiency, and occurs during use of the cutting device. Troubles caused by malfunctioning cutting blades can be suppressed.

  Below, the fiber cutting blade of this invention and the glass fiber cutting device which uses the fiber cutting blade are demonstrated based on an Example.

  FIG. 1 shows a partial cross-sectional view of the cutting edge of a fiber cutting blade used when manufacturing the glass chopped strand of the present invention. 1A is a partial plan view of the fiber cutting blade, and FIG. 1B is a partial cross-sectional view of FIG.

  The fiber cutting blade provided for the glass chopped strand cutting of the present invention has a Vickers hardness of Hv. Blade portion 10 (thickness 0.3 to 40 mm, width 2 to 15 mm) formed of a cemented carbide of 2200, and Vickers hardness Hv. And a base portion 20 (thickness 0.3 to 10 mm, width 5 to 50 mm) formed of 800 carbon steel tool. The blade portion 10 and the base portion 20 are bonded via a bonding alloy layer. The length of the alloy layer in the cross-sectional direction is 0.2 to 10 mm. A thin film layer made of a bonding material is formed on the surface of the blade portion 10, and a diffusion layer made of the bonding material is formed under the surface. The blade portion 10 has a shape inclined at an inclination angle α of 16.5 ° and an inclination angle β of 15.5 ° with respect to the blade axis in the direction of the blade axis from the blade edge P, and exhibits a so-called double-edged shape. is there. In addition, the shape of the tapered portion of the cutting edge is not curved and is a straight grind. Incidentally, both α and β are obtained by dividing the apex angle γ by a line segment connected to a point that bisects the bottom dimension of the cross section perpendicular to the blade width of the cutting blade from the vertex P, that is, the blade axis.

  The cutting edge length (cutting edge dimension) parallel to the blade axis of the inclined part 11a on one side and the inclined part 11b on the other side forming the both blades is the cutting edge length dimension La in the direction of the one-side blade axis. The cutting edge length dimension Lb parallel to the blade axis of 4.9 mm and the other side is 4.2 mm.

  Therefore, when confirming whether the tip angle of the blade satisfies the requirements as the fiber cutting blade of the present invention, | α−β | ÷ γ = (16.5-15.5) ÷ (16.5 + 15.5) = 0. The absolute value of the difference between the tip edge angle on both the one side and the other side is determined on both sides of the one side and the other side with respect to the one side cutting edge inclination angle and the other side cutting edge inclination angle forming the two blades. The numerical value divided by the sum of angles is 0.10 or less, which satisfies the requirement.

  Further, as to whether the length (cutting blade length) parallel to the blade axis of the inclined portion from the tip of the cutting edge satisfies the requirement as the fiber cutting blade of the present invention, (La−Lb) ÷ La = (4. 9-4.2) ÷ 4.9≈0.1429, where one side has a large cutting edge dimension in the direction of the blade axis from the tip of the cutting edge corresponding to the inclined part of the cutting edge and the cutting edge dimension in the direction of the blade axis from one side The ratio of the cutting edge dimension in one blade axis direction to the small dimensional difference on the other side is 0.40 or less, which satisfies the requirements of the present invention.

Said fiber cutting blade was produced in the procedure as shown below.
First, by blending 91% by mass of tungsten carbide (WC) powder having an average particle size of 0.05 to 1.2 μm and 9% by mass of cobalt (Co) powder, firing, and then performing HIP treatment The material of the blade part 10 made of a plate-like cemented carbide is produced.

  Further, the base part is formed by processing carbon tool steel containing 0.8% by mass of carbon (C) and subjected to quenching and tempering in accordance with the shape of the blade part 10.

Next, a bonding material foil having a thickness of 0.05 to 0.9 mm is disposed between the end face of the blade part 10 and the end face of the base part 20 and is abutted, and laser irradiation is performed near the tip of the base part. When the base portion 20 is heated and reaches a high temperature by this laser irradiation, the bonding material foil in contact with the end face of the base portion 20 is heated and melted by heat conduction from the base portion 20. Further, the blade member is heated by receiving heat conduction from the molten bonding material foil, and the blade member and the bonding material foil are integrally bonded to form the bonding material portion 15. At this time, the bonding material of the bonding material foil reacts with iron contained in the carbon tool steel forming the base portion to locally form a bonding material alloy layer on the surface layer of the base portion. The bonding material of the bonding material foil also dissolves in the cemented carbide and bonds with the diffusion layer of the bonding material. The thermal expansion coefficient of the alloy layer of this bonding material is 40 to 47 × 10 ⁻⁷ / K in the temperature range of 30 to 300 ° C., and the thermal expansion coefficient (25 to 200 ° C.) of the cemented carbide that is the material of the blade portion. for which approximates 45 × 10 ^-7 / K) in a temperature range, a small thermal stress remaining in the joint between the blade member and the base portion, the blade member and the base portion without causing deformation at the junction It is firmly joined. Then, a blade portion is formed by applying a cutting process or the like to the tip of the blade member to obtain a cutting blade.

  Next, FIG. 2 shows variations of the fiber cutting blade used when manufacturing the glass chopped strand of the present invention.

  As can be seen from FIG. 3, (A) shows straight grinds with the same taper portions 11a and 11b as in FIG. 1, and (B) shows the taper portions 11a1 and 11b1 convex outward with respect to the blade axis K. Represents a curved convex grind. Further, (C) represents a hollow grind in which the tapered portions 11a2 and 11b2 are curved outwardly with respect to the blade axis K in a concave shape. In (D), each tapered portion is formed of a curve having two curvatures, and the inflection points are represented by t1 and t2.

  And in any form, the symmetry of the taper part with respect to the blade axis is sufficiently high. Any of the cutting edge portions of (A) to (D) is a cemented carbide containing tungsten carbide, and its Vickers hardness has a value of 2000 or more. Vickers hardness in the range of 1 to 5.5 times.

  And about the structure which employ | adopted the cutting blade of Example 1 as a cutter blade and was arrange | positioned in the cutter roller 30, a conceptual diagram is shown in FIG.

  A plurality of cutting blades 10 were attached radially around the cutter roller 30 at equal intervals as shown in FIG. Using this fiber cutting device, the cutter roller 30 was rotated at a peripheral speed of 500 m / min, and the glass strand G was cut to a length of 3 mm. There was no decline, it could be used without problems, and stable production could be realized.

The fragmentary sectional view of the fiber cutting blade of this invention, (A) is a top view, (B) represents sectional drawing about the XY direction of (A). Explanatory drawing of the inclination | tilt angle regarding the fiber cutting blade of this invention. Explanatory drawing which shows the variation regarding the blade-tip shape of the fiber cutting blade of this invention. The fiber cutting device of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Fiber cutting blade part 15 Joining material part 20 Base | substrate part 11a, 11a1, 11a2, 11a3 One side blade edge inclination part 11b, 11b1, 11b2, 11b3 The other side blade edge inclination part 25 The bottom part 30 of fiber cutting blade Cutter roll 40 Rubber roll La Blade axis direction length dimension Lb of one side cutting edge inclined part Blade axis direction length dimension t1 of the other side cutting edge inclined part t2 Inflection point of curvature radius of one side tapered part T2 Inflection point of curvature radius of the other side tapered part K Blade axis α Inclination angle with respect to blade axis of one side inclined part β Inclination angle with other side inclined part with respect to blade axis γ Cutting blade tip angle P Cutting edge G Glass fiber T Chopped strand

Claims (5)

A fiber cutting blade to which a blade portion for cutting glass fiber and a base portion are fixed ,
The base portion is made of carbon tool steel,
A blade that is a straight line that connects the blade tip apex of the both blades and the equally divided point of the blade bottom side in a cross section perpendicular to the blade width, where the blade edge of the blade portion has a double-edged shape, and the apex angle of both the blades is γ When one of the two blade edge cross-sectional inclination angles at which the apex angle γ is divided by the axis is α and the other is β,
| Α-β | ÷ γ ≦ 0.10
A fiber cutting blade characterized in that the relationship is established. When the dimension parallel to the blade axis of one blade edge inclined portion of both blades is La, and the dimension parallel to the blade axis of the other blade edge inclined portion and equal to or smaller than La is Lb,
(La−Lb) ÷ La ≦ 0.40
2. The fiber cutting blade according to claim 1, wherein the relationship is established.   The fiber cutting blade according to claim 1 or 2, wherein a material of the blade portion is made of cemented carbide. Between the end surface of the blade portion and the end surface of the base portion , a bonding material foil having a thickness of 0.05 to 0.9 mm is disposed and bonded, and the Vickers hardness of the blade portion is 1.0 from the Vickers hardness of the base portion. fiber cutting blade according to any one of claims 1 to 3, wherein 5.5 times the value and to Rukoto. A glass roll continuously provided between two rolls is provided by providing a rubber roll pressed against the cutter roll and a cutter roll provided with a plurality of cutting blades, and the cutting blades are sequentially pressed against predetermined positions of the glass strand. A glass chopped strand having a desired size by cutting, a glass fiber cutting device having a structure for collecting the chopped strand after being cut at a lower part or a side part of a cutting mechanism having a cutting blade,
A glass fiber cutting device , wherein the cutter roll comprises the fiber cutting blade according to any one of claims 1 to 4.