JP2007260797A - Upper blade for guillotine type crop shears - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an upper blade of a guillotine type crop shear and a method of manufacturing the same. <P>SOLUTION: A rake angle of a blade root side straight blade of two straight blades continued to each other with a bending point between them in the blade width direction is formed larger than the rake angle of the blade tip side straight blade. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to an upper blade of a guillotine-type crop shear, and particularly relates to an excellent cutting ability and suitable for cutting high-strength steel.

  In the thick plate factory, both ends in the width direction of the steel sheet are cut with a side shear, and then both ends in the longitudinal direction are cut off with a guillotine type crop shear to form a rectangle.

  FIG. 6 schematically shows the structure of a guillotine type crop shear, which is placed between an upper blade 1 and a lower blade 3 having a rake angle θ, which is lifted upward, inside a gate-shaped housing (not shown). The upper blade 1 is dropped onto the steel plate 2 (dropping direction: arrow 5) and sheared.

  The rake angle θ of the guillotine type crop shear for steel plates is generally 0.5 to 5 °.

  In the guillotine type crop shear, the interval between the upper blade 1 and the lower blade 3 lifted upward is set so as to obtain a stroke 4 sufficient to shear the entire thickness t of the steel plate 2.

  The cutting force of the guillotine type crop shear depends on the pressing force of the upper blade 1 against the material to be cut and the rake angle θ of the upper blade 1 and increases the pressing force when cutting hard and thick hard-to-break material. Alternatively, the rake angle θ is increased.

  Increasing the pressing force cannot be easily implemented because it requires large-scale equipment construction that requires an increase in the driving device of the upper blade and reinforcement of the portal frame.

  When increasing the rake angle: 1. The size of the upper blade itself (the height of the blade edge at the blade base) remains the same, and only the rake angle is increased. By increasing the upper blade and rake angle.

  However, in the existing apparatus, the method for increasing only the rake angle without changing the size of the upper blade is that, as shown in FIG. 21 occurs.

  Further, as shown in FIG. 8, the method of increasing the upper blade and the rake angle may cause a portion 22 in contact with the blade base even when the upper blade 1 is lifted depending on the thickness t of the steel plate 2, and cutting. Therefore, the steel plate 2 cannot be moved under the upper blade.

Patent Document 1 relates to a shearing machine for thick steel plates having an increased rake angle and an improved cutting force. In a guillotine crop shear, the rake angle of the upper blade is constant at the center and increased toward both ends to increase the cutting edge. A shearing machine for thick steel plates that reduces the load on the gate-type frame during cutting, in which the shape in the width direction is substantially pan-bottom, is described.
Japanese Utility Model Publication 2-7911

  By the way, in the guillotine type crop shear, the upper blade is a consumable item and is appropriately replaced with a new one. For example, in the steel plate manufacturing field of a steel manufacturer, it is carried out about once every four weeks.

  On the other hand, in the field of thick plate demand, with the start of commercial trial production of API standard X120 steel using line pipe materials, the strength of steel materials has increased, and the load on shearing work tends to increase, improving shear capacity. Is desired.

  Therefore, there is a strong demand for an upper blade for replacement that can improve the cutting ability of an existing guillotine type crop shear and that is easy to manufacture and can be obtained at low cost. However, the upper blade used in the shearing machine for thick steel plate described in Patent Document 1 Is inferior in productivity because of its complicated shape, and because of its complicated shape, there is a concern about the influence on the dimensions of the steel sheet that can be cut with existing equipment.

  Then, an object of this invention is to provide the upper blade which is easy to manufacture and is excellent in cutting force, and its manufacturing method.

  The inventors of the present invention pay attention to the fact that the cutting load peak occurs in the initial stage of cutting and then decreases in the cutting of a guillotine crop shear using an upper blade having a straight blade (hereinafter referred to as a straight blade). The idea was to increase the rake angle of the blade edge in the area of the blade that is responsible for the initial cutting.

The object of the present invention can be achieved by the following means.
1. An upper blade for a guillotine type crop shear with a rake angle of the straight blade on the blade base side larger than the rake angle of the straight blade on the blade tip side of two continuous straight blades with the refraction point in the blade width direction.
2. The planar shape of the upper blade for a guillotine type crop shear of the two continuous blades with the refracting point in the blade width direction being larger than the rake angle of the blade on the blade edge side is larger than the rake angle on the blade edge side. It is a method for obtaining from the planar shape of an upper blade consisting of a single straight blade having a rake angle on the blade edge side, and the tip is previously cut by cutting the upper blade consisting of a single straight blade having a rake angle on the blade edge side The amount of biting that generates a load is obtained, and a refraction point obtained from the relationship between the amount of biting and the rake angle in the planar shape of the upper blade is provided on the straight blade of the upper blade. The rake angle of the blade is a straight blade having a single rake angle of the upper blade, and a straight blade having a rake angle larger than the rake angle is provided outside the planar shape of the upper blade from the refraction point. The blade base side of two continuous straight blades with the refraction point in the blade width direction Method for determining the planar shape of the guillotine on type crop for shear blade, wherein the rake angle of the straight blade and the cutting edge side of the straight edge of the planar shape of the large guillotine crop shear on blade than rake angle.
3. The upper blade for a guillotine-type crop shear according to 1, comprising a refraction point obtained by the following procedure.
However, the inflection point, a straight edge of the blade root side rake angle theta _1, straight blade edge side steps 1 and rake angle theta _2: In upper blade consisting of a straight blade rake angle theta _2, the bite of the upper blade The relationship between the amount and the cutting load is obtained, and after the peak load elapses, the bite amount d of the upper blade that can obtain a cutting load of 80 to 45% of the peak load is obtained.
Procedure 2: On the XY coordinates, plot the upper blade shape consisting of a straight blade with a rake angle θ ₂ with the blade base side end as the Y axis and its tip as the origin, and d / A point where tan θ ₂ is the X coordinate is taken as a refraction point.
Procedure 3: A straight line with a rake angle θ ₁ is drawn from the refraction point obtained in Procedure 2, and the intersection with the Y axis is taken as the tip of the new blade base side end.
Procedure 4: The straight line connecting the cutting edge side tip and the refraction point obtained in step 3 is the straight blade on the cutting edge side, and the straight line connecting the refraction point to the cutting edge tip is the straight blade on the cutting edge side.
4). An upper blade for a guillotine type crop shear having a plurality of refraction points in the blade width direction and having continuous straight blades, and the rake angle of each straight blade extends from the straight blade on the blade base side to the straight blade on the blade edge side. An upper blade for a guillotine-type crop shear characterized by increasing sequentially.

According to the present invention, the following effects are obtained, which is extremely useful industrially.
1. When cutting existing equipment, the peak load at the time of cutting is reduced, so that the reaction force acting on the frame and the cutting edge at the time of cutting is reduced, and the equipment life and upper blade life are extended.
2. Since the peak load at the time of cutting becomes small, it is possible to cut a steel material with higher strength with existing equipment. Furthermore, since the cutting edge is refracted in two steps, there is no need to change the cuttable dimension.
3. Equipment that is smaller than existing equipment and has the same cutting ability as existing equipment is possible.

  FIG. 3 is a diagram schematically showing the relationship between the amount of biting into the steel material and the cutting load in the cutting of the guillotine type crop shear. The cutting load of the guillotine type crop shear is the first peak value (below) After reaching the peak load, the steady maximum load is gradually stabilized. FIG. 5 is a diagram showing the relationship between the peak load / steady maximum load ratio and the cutting load. From the figure, the steady maximum load is about 80 to 45% of the peak load.

  FIG. 4 is a diagram showing the relationship between the amount of biting when the peak load is generated and the material plate thickness. When the amount of biting is about 30 to 80% of the plate thickness, the peak load is generated.

  In the present invention, in order to reduce the peak load, at the initial stage of cutting, the rake angle of the blade that bites into the material is made larger than the rake angle of the blade that starts to bite into the material after the peak load occurs. To do.

FIG. 1 is a top view schematically illustrating the shape of an upper blade according to the present invention. In the figure, 1 is an upper blade, 11 and 12 are straight blades, 13 is a back, 14 is a blade base, 15 is a blade edge, h ₁ is the blade surface height at the blade edge, h ₂ is the blade surface height at the blade edge, and h ₃ is the blade surface height at the refraction point.

Upper blade 1 across the refraction point c in the direction of the blade width W, has two straight edges 11, 12 successive rake angle theta ₁ of the straight edge 11 of the blade root side of the cutting edge side of the straight blade 12 greater than the rake angle θ _2.

Since the straight blade 11 on the blade base side takes charge in the initial stage of cutting, the peak load is reduced as compared with the case of cutting with an upper blade made of a straight blade having the same rake angle θ ₂ as the straight blade 12 on the blade edge side. . Hereinafter, the procedure for determining the upper blade shape shown in FIG. 1 will be specifically described with reference to FIG.

Figure 2 shows the upper blade (hereinafter, upper blades consisting of a straight blade rake angle theta ₂₎ on the XY coordinate axes of the external shape by adding a straight-edge rake angle θ1 of a single straight cutting edge rake angle theta ₂ in FIG, 1 'in the figure at upper blade consisting of a straight blade 12 of the rake angle theta _2, the four peripheries portions a, B, C, and D.

Procedure 1: With the upper blade 1 ′ composed of a straight blade with a rake angle θ ₂ , the relationship between the amount of biting of the upper blade shown in FIG. 3 and the cutting load is obtained, and after the peak load has elapsed, the cutting load is the peak The amount of biting d of the upper blade that is 80 to 45% of the load is obtained.

Next, in order to reduce the peak load to a cutting load having a magnitude of 80 to 45% of the peak load, the rake angle of the portion of the straight blade 12 responsible for cutting from the start of cutting until the peak load is generated. Is larger than the rake angle θ ₂ .

Assuming that the amount of biting when the point load is generated by the upper blade 1 ′ having a straight blade with a rake angle θ ₂ is d, the cutting length from the steel plate end on the steel plate surface is d / tan θ ₂ . The position of the refraction point E is specified using the geometric relationship shown in FIG.

Procedure 2: On the XY coordinates, plot the shape of the upper blade 1 ′ composed of the straight blade 12 with the rake angle θ ₂ with the edge 14 ′ on the blade base side as the Y axis and the tip B as the origin, A point where d / tan θ ₂ is the X coordinate on the blade 12 is defined as a refraction point E.

Procedure 3: A straight line having a rake angle θ ₁ is drawn from the refraction point E obtained in Procedure 2, and the intersection with the Y-axis is set as a new tip B ′ of the edge 14 ′ on the blade base side.

  Step 4: The straight line connecting the tip B ′ and the refraction point E obtained in Step 3 is the straight blade 11 on the cutting edge side, and the straight line connecting the cutting edge C from the refraction point E is the straight blade 12 on the cutting edge side. .

Incidentally, rake angle theta ₁ straight blade blade root side from inflection point is not particularly specified well greater than the rake angle theta ₂ of the straight blade cutting edge side. However, when the rake angle theta ₁ is too large, the non-cutting area is generated in the steel, it is necessary to determine appropriate according to steel dimensioned to disconnect.

Since the amount of bite, as shown in FIG. 4 is a peak load of about 30% to 80% of the plate thickness occurs, cutting surface height h ₃ of the inflection point c is the formula which is obtained from the geometric relationship It is also possible to set so as to satisfy. However, θ ₂ is the rake angle of the straight blade on the blade edge side as θ ₂ .
(Blade surface height h ₂ + blade width W × tan θ ₂ ) −0.8 × steel plate thickness t ≦ h ₃ ≦ (blade surface height h ₂ + blade width W × tan θ at the blade edge) ₂ ) -0.3 x thickness t of steel material to be cut
When the width of the upper blade is wider than the width W of the steel material to be cut, the shape of the blade edge is obtained for the width W portion of the steel material, and then the width is extended along the rake angle.

  In the above description, the case where there is one refraction point has been described. However, if a refraction point is provided on the straight blade on the blade base side, and the rake angle is sequentially increased from the blade base side to the blade edge side, the cutting at the initial stage of cutting is performed. A rise in load is moderated, and a cut surface having excellent surface properties is obtained, which is preferable.

Example of the present invention. Example of the present invention. The figure which shows the relationship between a cutting load and the amount of bite. The figure which shows the relationship between the amount of biting and the board thickness of a cutting material. The figure which shows the relationship between the peak load in a cutting load, and a steady maximum load. Conventional example. Conventional example. Conventional example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Upper blade 11, 12 Straight blade 13 Back 14 Cutting edge 15 Cutting edge 2 Non-cutting material (steel material)
21 Uncut portion 22 Contact portion 3 Lower blade 4 Stroke 5 Reduction direction h ₁ Blade height h ₂ Blade height h ₃ Blade height θ, θ ₁ , θ ₂ rake angle at refraction point

Claims (4)

  An upper blade for a guillotine-type crop shear whose rake angle of the straight blade on the blade base side is larger than the rake angle of the straight blade on the blade tip side of two continuous straight blades with the refraction point in the blade width direction.   The planar shape of the upper blade for a guillotine-type crop shear with the rake angle of the straight blade on the blade base side larger than the rake angle of the straight blade on the blade tip side of the two continuous straight blades with the refraction point in the blade width direction It is a method for obtaining from the planar shape of an upper blade consisting of a single straight blade having a rake angle on the blade edge side, and the tip is previously cut by cutting the upper blade consisting of a single straight blade having a rake angle on the blade edge side The amount of biting that generates a load is obtained, and a refraction point obtained from the relationship between the amount of biting and the rake angle in the planar shape of the upper blade is provided on the straight blade of the upper blade, and the straight edge on the blade base side from the refraction point is provided. The rake angle of the blade is a straight blade having a single rake angle of the upper blade, and a straight blade having a rake angle larger than the rake angle is provided outside the planar shape of the upper blade from the refraction point. The blade base side of two continuous straight blades with the refraction point in the blade width direction Method for determining the planar shape of the guillotine on type crop for shear blade, wherein the rake angle of the straight blade and the cutting edge side of the straight edge of the planar shape of the large guillotine crop shear on blade than rake angle. The upper blade for a guillotine-type crop shear according to claim 1, comprising a refraction point obtained by the following procedure. However, the inflection point, a straight edge of the blade root side rake angle theta _1, straight blade edge side steps 1 and rake angle theta _2: In upper blade consisting of a straight blade rake angle theta _2, the bite of the upper blade The relationship between the amount and the cutting load is obtained, and after the peak load elapses, the bite amount d of the upper blade that can obtain a cutting load of 80 to 45% of the peak load is obtained.
Procedure 2: On the XY coordinates, plot the upper blade shape consisting of a straight blade with a rake angle θ ₂ with the blade base side end as the Y axis and its tip as the origin, and d / A point where tan θ ₂ is the X coordinate is taken as a refraction point.
Procedure 3: A straight line with a rake angle θ ₁ is drawn from the refraction point obtained in Procedure 2, and the intersection with the Y axis is taken as the tip of the new blade base side end.
Procedure 4: The straight line connecting the cutting edge side tip and the refraction point obtained in step 3 is the straight blade on the cutting edge side, and the straight line connecting the refraction point to the cutting edge tip is the straight blade on the cutting edge side. An upper blade for a guillotine type crop shear that has a plurality of refraction points in the blade width direction and has continuous straight blades, and the rake angle of each straight blade extends from the straight blade on the blade base side to the straight blade on the blade edge side. An upper blade for a guillotine-type crop shear characterized by increasing sequentially.

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