JP2007307658A - Cutting tool grinding device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cutting tool grinding device surely forming a symmetrical clam-like small blade on the blade tip of a ground cutting tool with a simple structure. <P>SOLUTION: The cutting tool grinding device is provided with a plurality of endless belts 52 arranged to be crossed with each other and forming a V-shape grinding groove 54 for receiving the blade tip of the cutting tool, and driven pulleys 20 and driving pulleys winding and supporting the endless belts 52 in a freely travelling manner. The endless belts 52 is deformed elastically when the cutting tool is pressed to the grinding groove 54. The device is also provided with a guide rod 58 arranged at a position diagonal to the cutting tool while interposing the cross position of the endless belts 52 therebetween, and abutting the endless belts 52 when the cutting tool is ground and adjusting the crossed angle of the endless belts 52 to a desired angle. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a blade polishing apparatus.

Some blade polishing apparatuses are provided with a plurality of endless belts, and these endless belts cooperate with each other to form a V-shaped polishing groove (for example, Patent Document 1).
According to Patent Document 1, when the cutting edge of the blade is pressed against the polishing groove of the blade polishing apparatus, the apex angle of the polishing groove changes to an angle that balances the knife lowering force and the repulsive force of the endless belt. Then, the angle of the blade edge of the polished blade is considered to be equal to the apex angle of the polished groove after the change, and the shape of the blade edge is considered to be a bowl shape.
JP 49-64992 A

  In the blade polishing apparatus of Patent Document 1, the apex angle of the polishing groove changes according to the pressing force when the blade edge of the blade is pressed against the polishing groove. As a result, the apex angle of the polishing groove changes without being stable, and there is a possibility that the shape of the cutting edge of the cutter does not surely become a bowl shape. Further, the endless belts on both sides of the cutter do not have the same elastic deformation amount, and the shape of the cutting edge may become asymmetrical when viewed in cross section.

  The present invention has been made based on the above-described circumstances, and an object of the present invention is to provide a blade polishing apparatus in which a symmetrical symmetrical bowl-shaped small blade is reliably formed on a blade edge of a polished blade with a simple configuration. Is to provide.

  In order to achieve the above object, according to the present invention, a plurality of endless belts arranged so as to cross each other and forming a V-shaped polishing groove for receiving a cutting edge of a cutter, And a pulley row that movably supports the endless belt, wherein the endless belt is elastically deformable when a cutter is pressed against the polishing groove, and sandwiches the crossing position of the endless belt. The blade polishing apparatus is provided with a regulating member that is disposed at a diagonal position with respect to the blade and that abuts against the endless belt at the time of polishing the blade and sets a crossing angle of the endless belt to a desired angle. Is provided (claim 1).

  In the blade polishing apparatus according to the first aspect of the present invention, the apex angle of the polishing groove during use is set to be stable at a desired angle according to the user who uses the apparatus by the regulating member. As a result, according to this polishing apparatus, a symmetrical ridge-shaped small blade is reliably formed on the cutting edge of the polished blade.

  FIG. 1 shows a blade polishing apparatus according to an embodiment, and the blade polishing apparatus has a rectangular base plate 2. Two brackets 4 and 4 having an L-shaped cross section are fixed to the upper surface of the base plate 2, and these brackets 4 and 4 are located on both sides of the base plate 2 in the width direction. A bottom wall portion 4 a of each bracket 4 is fixed to the base plate 2 by a plurality of bolts 6, and a side wall portion 4 b of each bracket 4 extends perpendicular to the base plate 2.

The leg 8a of the stage 8 is fixed to the outer surface of each side wall 4b by two bolts 10. The upper end of the leg portion 8a is perpendicular to the lower surface of the pedestal portion 8b of the stage 8, and the pedestal portion 8b is parallel to the base plate 2.
As shown in FIG. 2, two stages 8 are fixed to the side wall 4b of the left bracket 4 as viewed in FIG. 1, and three stages 8 are fixed to the side wall 4b of the right bracket 4. Has been. The plurality of stages 8 fixed to the same bracket 4 are arranged in the longitudinal direction of the base plate 2, and the two stages 8 fixed to the left bracket 4 in the longitudinal direction of the base plate 2 are It is located between the three stages 8 fixed to the right bracket 4.

  On the upper surface of the pedestal portion 8b of each stage 8, the base end portion of the beam 12 is fixed by two bolts 14. Each beam 12 extends toward the center in the width direction of the base plate 2 beyond the end edge of the base portion 8b. A pulley support member 16 having a U-shape in plan view is fixed to the distal end portion of each beam 12, and a rotation shaft 18 is spanned between the side wall portions 16a facing each pulley support member 16. . Each rotary shaft 18 extends in the longitudinal direction of the base plate 2, and the three or two rotary shafts 18 supported by the same bracket 4 are arranged in a straight line. 2, the three right rotation shafts 18 and the two left rotation shafts 18 are parallel to each other, but are separated from each other in the width direction of the base plate 2.

A driven pulley 20 is attached to each rotating shaft 18, and two radial bearings 22 are disposed between the rotating shaft 18 and the driven pulley 20. Accordingly, the driven pulley 20 is rotatably supported by the radial bearing 22.
The diameter of the driven pulley 20 is smaller than the distance between the three rotating shafts 18 and the two rotating shafts 18, and the driven pulley 20 attached to the right rotating shaft 18 as viewed in FIG. The driven pulley 20 is separated from the base plate 2 in the width direction.

Note that outward flanges 24 and 24 are formed at both ends of each driven pulley 20.
On the other hand, as shown in FIG. 3, an electric motor 32 is fixed to the upper surface of the base plate 2 via a fixed frame 30, and the electric motor 32 is connected to the brackets 4, 4 in the longitudinal direction of the base plate 2. Is on the opposite side. The electric shaft 34 of the electric motor 32 extends in the longitudinal direction of the base plate 2 and is connected to the base end portion of the drive shaft 38 via a connecting sleeve 36. The drive shaft 38 also extends in the longitudinal direction of the base plate 2, and the tip side portion of the drive shaft 38 extends between the two brackets 4, 4.

  Three drive pulleys 40 are fixed at equal intervals on the front end portion of the drive shaft 38, and the pulley 40 can rotate integrally with the drive shaft 38. The drive shaft 38 passes through two support plates 42 erected on the upper surface of the base plate 2, and a radial bearing 44 is disposed between the drive shaft 38 and the support plate 42. Accordingly, the drive shaft 38 is rotatably supported by the radial bearing 44. The drive pulley 40 also has outward flanges 45, 45 at both ends.

  A drive gear 46 is fixed to the base end side portion of the drive shaft 38, and the drive gear 46 meshes with the driven gear 48. The driven gear 48 is fixed to the proximal end side portion of the driven shaft 50, and the driven shaft 50 extends in parallel with the drive shaft 38. A portion on the distal end side of the driven shaft 50 also extends between the brackets 4 and 4, and two drive pulleys 40 are fixed to the portion on the distal end side of the driven shaft 50 at equal intervals. The driven shaft 50 passes through two support plates 42 different from the drive shaft 38, and is rotatably supported by a radial bearing 44.

  Here, the distance between the drive shaft 38 and the driven shaft 50 is smaller than the radius of the drive pulley 40, and the two drive pulleys 40 fixed to the driven shaft 50 when viewed in the axial direction of the drive shaft 38 and the driven shaft 50. Is located between three drive pulleys 40 fixed to the drive shaft 38. In other words, when viewed in the axial direction of the drive shaft 38 and the driven shaft 50, the drive pulley 40 fixed to the driven shaft 50 and the drive pulley 40 fixed to the drive shaft 38 are alternately arranged.

  The driven pulleys 20 described above are positioned one above the respective driving pulleys 40, and the driven pulleys 20 and the driving pulleys 40 that are positioned above and below are paired. Then, referring to FIG. 1 again, one endless belt 52 is wound around the pair of driven pulleys 20 and the drive pulley 40. The endless belt 52 is wound around with an appropriate tension, and a portion of the endless belt 52 extending between the driven pulley 20 and the driving pulley 40 forms a linear portion extending substantially linearly.

  The endless belt 52 is a belt made of, for example, a SUS powder diamond electrodeposited steel strip or a powder diamond nonwoven fabric, and the surface of the endless belt 52 forms a polished surface in which diamond powder as abrasive grains is distributed. When a powdered diamond nonwoven fabric is used, even if the endless belt 52 is worn, the diamond powder in the nonwoven fabric appears one after another, so that the polished surface is not worn.

  As seen in FIG. 1, the linear portion 52 a of the endless belt 52 that is looped around the driving pulley 40 fixed to the driving shaft 38 and the linear portion of the endless belt 52 that is looped to the driving pulley 40 fixed to the driven shaft 50. 52a intersects between the driven pulley 20 and the drive pulley 40. The straight portions 52a and 52a of the endless belts 52 and 52 that intersect with each other form a V-shaped polishing groove 54 above the crossing position, and the opening width of the polishing groove 54 is in the width direction of the base plate 2 The distance between the driven pulleys 20 is defined.

  Further, the straight portions 52a of the endless belt 52 that intersect with each other define a V-shaped space 56 that is symmetrical with the polishing groove 54 below the intersecting position. Two guide rods 58 are disposed so as to penetrate the space 56, and each guide rod 58 extends in the longitudinal direction of the base plate 2. The two guide rods 58 are separated from each other in the width direction of the base plate 2, and the distance (height) from the base plate 2 is equal to each other. The guide rods 58 are also arranged symmetrically as viewed in FIG. 1, and the outer peripheral surface of each guide rod 58 is in contact with the back surface of the linear portion 52a.

Here, as shown in FIG. 4, in this blade polishing apparatus, when the apex angle of the polishing groove 54 when not in use is α, α is set to 20 degrees, for example. When the blade polishing apparatus is used, that is, when the apex angle of the polishing groove 54 when the cutting edge 62 of the blade 60 is pressed against the polishing groove 54, β is set to be 30 degrees, for example.
More specifically, although the endless belt 52 has flexibility, the straight portion 52a of the endless belt 52 is not bent when the blade polishing apparatus is not used. For this reason, when the apex angle is α, each guide rod 58 is only slightly in contact with the straight portion 52a. The apex angle α is expressed by the following formula (1).

tan (α / 2) = (D / 2 + R / cos (α / 2)) / L1 (1)
In Equation (1), D is the distance between the centers of the guide rods 58, and R is the radius of the guide rods 58. L1 is a distance in the vertical direction from the intersection position X1 of the endless belt 52 to the center of the guide rod 58.
On the other hand, when the blade polishing apparatus is used, the endless belt 52 bends to allow the apex angle of the polishing groove 54 to increase due to its flexibility. That is, when the cutting edge 62 of the blade 60 is pressed against the polishing groove 54, the linear portions 52a of the endless belt 52 are elastically deformed and intersect each other at the intersecting position X2. At this time, the contact area of the endless belt 52 with the guide rod 58 is increased, and the apex angle β of the polishing groove 54 is expressed by the following equations (2) and (3).

tan (β / 2) = (D / 2 + R / cos (β / 2)) / L3 (2)
L3 = L1-L2 (3)
In Expression (3), L2 is the distance between the intersection position X1 and the intersection position X2.
In the above-described blade polishing apparatus, the elastic modulus of the endless belt 52 can be selected so that the apex angles α and β have desired values according to the force with which the user presses the blade. Further, the center distance D and the distances L1, L2, and L3 between the guide rods 58 can be adjusted, and the relative position of the driven pulley 20 with respect to the drive pulley 40 can be changed.

  Specifically, referring again to FIG. 1, a guide groove 70 extending vertically is formed on the outer surface of the side wall portion 4 b of the bracket 4, and the leg portion 8 b of the stage 8 is slidably fitted into the guide groove 70. ing. On the other hand, a long hole 72 that is long in the vertical direction is formed in the leg 8b, and the bolt 10 is screwed into a female screw that passes through the long hole 72 and is formed in the side wall 4b of the bracket 4. Therefore, if the bolt 10 is loosened and the leg portion 8b of the stage 8 is moved in the vertical direction along the guide groove 70, the height of the driven pulley 20 from the base plate 2 is set to a desired height. Can do.

  A horizontally extending guide groove 74 is formed on the upper surface of the pedestal portion 8b of the stage 8, and the beam 12 is slidably fitted in the guide groove 74. On the other hand, a long hole 76 that is long in the horizontal direction is formed in the beam 12, and the bolt 14 passes through the long hole 76 and is screwed into a female screw formed in the base portion 8 b of the base 8. Therefore, if the bolt 14 is loosened and the beam 12 is moved in the horizontal direction along the guide groove 74, the position of the driven pulley 20 in the horizontal direction can be set to a desired position.

Hereinafter, a method for polishing a blade using the above-described blade polishing apparatus will be described.
In order to use the blade polishing apparatus, first, the electric motor 32 is activated to rotate the drive pulley 40, and the endless belt 52 is caused to travel. Thereafter, the blade edge 62 is polished by reciprocating the blade edge 60 several times in the blade spanning direction while pressing the blade edge 62 of the blade 60 against the polishing groove 54 while holding the blade with one hand.

Here, when pressed by the blade edge 62 of the blade 60 during polishing, the endless belt 52 is elastically deformed and bent. As the endless belt 52 bends, the crossing position of the endless belt 52 moves downward from X1 to X2, and the apex angle of the polishing groove 54 changes from α to β.
In this way, when the apex angle of the polishing groove 54 becomes β with the endless belt 52 bent by the guide rod 58, the cutting edge 62 of the cutting tool 60 is symmetrical to the cutting edge 62 as shown in FIG. A small bowl-shaped blade 64 is reliably formed.

  The small blade 64 is an isosceles triangular section formed at the tip of the cutting edge 62 of the cutting tool 60, and the bowl-shaped small blade 64 is a convex shape in which both side surfaces of the small blade 64 are rounded. It means being finished. When the bowl-shaped small blade 64 is formed on the blade edge 62 of the blade 60, the blade can be separated from the workpiece when cutting with the blade 60. Further, since the small blade 64 is thick, it is difficult for the blade to spill, and the sharpness is maintained for a long time.

In the blade 60 polished by using the above-described blade polishing apparatus, as shown in a circle in FIG. 6, the small blade 64 is formed in an area of approximately 0.02 mm to 0.2 mm from the tip of the blade edge 62 in the blade 60. The The width at the tip of the small blade 64 (small blade edge r) is in the range of 0.0005 mm to 0.0015 mm, and the size of the irregularities (small sawtooth) at the tip of the small blade 64 is in the range of 0.0005 mm to 0.001 mm. Become.
In the polished blade 60, the angle of the blade edge 62 is preferably approximately 18 ° to 22 °, and the angle of the small blade 64 is preferably approximately 28 ° to 32 °. In this case, the angles of the blade edge 62 and the small blade 64 can be easily and reliably within a preferable range.

That is, since the apex angles α and β of the polishing groove 54 correspond to the angle of the cutting edge 62 and the angle of the small blade 64 in the polished blade 60, the apex angle α is set to approximately 18 ° to 22 °, and the guide If the apex angle β is set to approximately 28 ° to 32 ° by the rod 58, the angles of the blade edge 62 and the small blade 64 can be easily and reliably within a preferable range.
Although the description is finished above, the present invention is not limited to the above-described embodiment, and it is needless to say that various modifications are possible.

It is a schematic sectional drawing of the blade grinding | polishing apparatus of one Embodiment which follows the II line | wire of FIG. It is a schematic top view of the upper part from the stage in the blade grinding | polishing apparatus of FIG. It is the schematic top view which notched a part of upper part rather than the stage in the blade grinding | polishing apparatus of one Embodiment. It is a figure for demonstrating the function of the guide rod in the blade grinding | polishing apparatus of FIG. It is a figure which shows the outline of the grinded blade using the blade grinder of FIG.

Explanation of symbols

20 Driven pulley (pulley train)
40 Drive pulley (pulley train)
52 Endless belt
54 Polishing groove
58 Guide rod (regulating member)

Claims (1)

A plurality of endless belts arranged so as to intersect with each other and forming a V-shaped polishing groove for receiving a cutting edge of a cutter, and a pulley row on which the endless belt is wound and supports the endless belt so as to run freely In the blade polishing apparatus, the endless belt is elastically deformable when the blade is pressed against the polishing groove,
A regulating member that is disposed diagonally with respect to the blade across the crossing position of the endless belt, and that abuts the endless belt when polishing the blade so that the crossing angle of the endless belt is a desired angle; A blade polishing apparatus characterized by the above.

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