TWI797592B - metal saw - Google Patents

Abstract

Prevents the blade of the metal saw from being worn in the thickness direction.

Metal saws with blades formed on the outer periphery, the metal saws are integrally has a first plate, a third plate, and a second plate between the first plate and the third plate, and the saw blade has: the first plate, the second A plurality of cutting blades formed by two plates and a third plate; a plurality of backs formed by the second plate on the rear side of each of the plurality of cutting blades in the direction of rotation of the metal saw; The rigidity of the first plate-shaped object and the third plate-shaped object is higher than that of the second plate-shaped object, and the toughness of the second plate-shaped object is higher than that of the first plate-shaped object and the third plate-shaped object. The first plate-shaped object and the third plate-shaped object may have a whetstone. The constituent elements and their ratios of the first plate may be different from those of the second plate.

Description

metal saw

The present invention relates to a metal saw used when cutting ceramics before sintering.

There is a multilayer ceramic capacitor as one of semiconductor devices used in mobile phones and the like. The multilayer ceramic capacitors are hundreds of them installed in a mobile phone, and they are mass-produced and consumed in large quantities every day.

A laminated ceramic capacitor is manufactured by first laminating a plurality of plates of ceramic raw materials (ceramics before sintering), which are divided into individual chip capacitors by a cutting device, and then sintered. In addition, if the division by the cutting device is performed after sintering, thermal deformation will occur due to the high temperature during sintering, the arrangement of chip capacitors will be distorted, and precise cutting will become difficult, so the division is performed before the sintering of ceramics.

The process of dividing a plurality of plate-shaped laminates of ceramic raw materials into individual chip capacitors through a cutting device is implemented through a cutting device equipped with a metal saw. In Patent Document 1, a metal saw (rotary knife) has been disclosed, which is used for cutting ceramic raw materials, and a saw blade is formed on the outer periphery.

[Prior Art Literature]

[Patent Document]

[Patent Document 1] Japanese Patent Laid-Open No. 4-179505

In addition, when the ceramic raw material is repeatedly cut by the metal saw, the saw blade on the outer periphery of the metal saw is worn out. In particular, the angle between the two end portions in the thickness direction of the cutting surface (the surface between one side and the other side of the metal saw) of the saw blade (the angle between the side surface of the metal saw and the cutting surface) causes a large cutting load. , so the wear is strong, and the saw blade gradually changes to the shape where the corner is rounded.

When the corners of the saw blade of the metal saw are worn away and the corners are rounded, this shape is reflected in the processed portion at the cutting site of the ceramic raw material being cut. For this reason, there is a problem that the side surfaces of the individual chip capacitors produced by dividing also have a shape reflecting the shape.

This invention was made in view of this problem, and it aims at providing the metal saw which suppresses the abrasion of the corner|angular part of a saw blade. Furthermore, it is to provide a metal saw which does not have an abnormal shape on the side surface of the formed chip capacitor even when it is used when dividing a ceramic raw material.

According to one aspect of the present invention, there is provided a metal saw that forms a saw blade on an outer peripheral portion, and integrally has a first plate, a third plate, and a space between the first plate and the third plate. The second plate, the saw blade tie There are: a plurality of cutting blades formed by the first plate, the second plate, and the third plate; on the rear side of each of the plurality of cutting blades in the direction of rotation of the metal saw, the second A plurality of backs formed by plates.

According to another aspect of the present invention, there is provided a metal saw that has a saw blade formed on the outer peripheral portion, and integrally has a first plate, a third plate, and a gap between the first plate and the third plate. Between the second plate, the saw blade has: a plurality of cutting edge parts formed by the first plate, the second plate, and the third plate; each of the plurality of cutting edge parts The rear side of the rotation direction of the metal saw is composed of a plurality of backs formed by the first plate or the third plate.

In addition, according to another aspect of the present invention, there is provided a metal saw in which a saw blade is formed on the outer peripheral portion, and integrally has a first plate-shaped object, a third plate-shaped object, and the first plate-shaped object and the third plate-shaped object. The second plate-shaped object between objects, the saw blade has: a plurality of cutting edge parts formed by the first plate-shaped object, the second plate-shaped object, and the third plate-shaped object; The respective rear sides of the metal saw in the direction of rotation are a plurality of backs formed by the second plate; the first plate and the third plate are more rigid than the second plate.

According to another aspect of the present invention, there is provided a metal saw that has a saw blade formed on the outer peripheral portion, and integrally has a first plate, a third plate, and a gap between the first plate and the third plate. Between the second plate, the saw blade has: a plurality of cutting edge parts formed by the first plate, the second plate, and the third plate; each of the plurality of cutting edge parts The rear side of the rotation direction of the metal saw is composed of a plurality of backs formed by the first plate-shaped object or the third plate-shaped object; the first plate-shaped object and the third plate-shaped object are more rigid than the second plate-shaped object Things are high.

Furthermore, according to another aspect of the present invention, a A metal saw having a saw blade formed on its outer periphery, the metal saw integrally having a first plate, a third plate, and a second plate between the first plate and the third plate, The saw blade system has: a plurality of cutting edge parts formed by a first plate, a second plate, and a third plate; behind each of the plurality of cutting blades in the direction of rotation of the metal saw A plurality of backs formed by the second plate-shaped object; the first plate-shaped object and the third plate-shaped object are more rigid than the second plate-shaped object, and the second plate-shaped object is tougher than the second plate-shaped object The 1st plate and the 3rd plate are high.

Furthermore, according to another aspect of the present invention, there is provided a metal saw in which a saw blade is formed on an outer peripheral portion, and the metal saw integrally has a first plate, a third plate, the first plate The second plate-shaped object between the third plate-shaped object, the saw blade has: a plurality of cutting edge parts formed by the first plate-shaped object, the second plate-shaped object, and the third plate-shaped object; Respective rear sides of the plurality of cutting blades in the direction of rotation of the metal saw are formed by a first plate or a third plate; the first plate and the third plate are rigid It is higher than the second plate-shaped object, and the toughness of the second plate-shaped object is higher than that of the first plate-shaped object and the third plate-shaped object.

In addition, in the metal saw related to one aspect of the present invention, the first plate-shaped object and the third plate-shaped object may have a sharpening material. In addition, in the metal saw related to one aspect of the present invention, the constituent elements and their ratios of the first plate-shaped object may be different from the constituent elements and their ratios of the second plate-shaped object.

According to an aspect of the present invention, the first to third plates are provided A metal saw that rotates as one piece. The metal saw according to one aspect of the present invention is formed by integrating three or more plate-shaped objects, so individual properties can be independently set. For example, a plate-shaped object having high rigidity and a plate-shaped object having high toughness may be laminated and combined in a plurality in the thickness direction.

For example, when a highly rigid plate is arranged on both side surfaces, the wear resistance of the corner portion of the saw blade of the metal saw is improved. Then, when a plate with high toughness is arranged between plates with high rigidity, the metal saw becomes stronger against external force, impact, etc., and the durability of the metal saw is improved.

Furthermore, when cutting ceramics with a metal saw that has a high-rigidity plate on both sides that are easily exposed to friction and a low-rigidity plate on the inner side that is not easily exposed to friction, the cutting surface of the metal saw will be damaged. Consume evenly. In other words, only the corners of the saw blade of the metal saw are not worn away to become rounded. Therefore, the side surfaces of the formed chip capacitors will not have abnormal shapes.

In addition, in the metal saw related to an aspect of the present invention, the saw blade has a cutting edge portion and a back portion. The cutting edge for cutting ceramics is made up of the first to third plates, which can ensure sufficient thickness for the part used for cutting. On the other hand, on the back of the part not used for cutting, there are the first plate and the third plate on the side without the saw blade, so the space for effectively removing the chips generated during cutting is ensured.

For this reason, abrasion during cutting of the corner portion at the tip of the cutting edge portion of the saw blade can be reduced. In addition, such a shape with a cutting edge and a back can be easily formed by simply adjusting the shape of each plate without performing complicated processing on the metal saw, thereby suppressing the cost related to the manufacture of the metal saw.

Therefore, according to an aspect of the present invention, thereby providing A metal saw that suppresses abrasion of corners. In addition, there is provided a metal saw that does not have an abnormal shape on the side surface of the chip capacitor formed when it is used when dividing a ceramic raw material.

2: Cutting device

4: Subject

6: Display monitor

8: Exterior cover

10: Cutting unit

12: Holding table

14: Carrying table

16: Spindle shell

18: Spindle

18a: opening

20: rear flange

22: Flange

22a: opening

22b: Contact surface

24: convex part

26: Fixing bolt

26a: Outer peripheral surface

28: Metal Saw

28a: opening

28b: saw blade

28c: cutting edge

28d: back

30: front flange

30a: opening

32: fixed nut

32a: opening

32b: Inner wall surface

34: knife cover

36: Knife cover body

38: slide cover

40: Cylinder

42: Connector

44: Nozzle

46: Connector

48: Connector

50a: the first plate

50b: the second plate

50c: the third plate

52a: Opening of the first plate

52b: Opening of the second plate

52c: Opening of the third plate

[ Fig. 1 ] A perspective view showing an example of a cutting device.

[ Fig. 2 ] A perspective view schematically illustrating the configuration of a cutting unit.

[ Fig. 3 ] Fig. 3(A) is a schematic diagram of the metal saw viewed from the side, and Fig. 3(B) and Fig. 3(C) are diagrams schematically illustrating the cross-sectional structure of the metal saw.

[FIG. 4] FIG. 4(A) is a schematic diagram of a metal saw related to another embodiment viewed from the side, and FIG. 4(B) and FIG. 4(C) are diagrams schematically illustrating a cross-sectional structure of a metal saw. .

Embodiments related to the present invention will be described. As an example of a cutting device using a metal saw according to this embodiment, an external perspective view of a cutting device 2 for cutting a workpiece such as ceramics is shown in FIG. 1 . The cutting device 2 is composed of a main body 4 and a display monitor 6. The main body 4 is provided with a cutting unit 10 of the metal saw and is housed in an exterior cover 8. The display monitor 6 is mounted on the outside of the main body 4. Cover 8.

A touch panel type display monitor 6 is arranged on the front surface of the exterior cover 8 . Through this display monitor 6, the operator inputs instructions for the device Order, and simultaneously the operating status of the device is displayed on the display monitor 6.

The cutting unit 10 is configured to be movable in the Y-axis direction. The holding table 12 is adjacent and the cutting unit 10 is arranged so as to be movable in the X-axis direction. The holding table 12 holds the workpiece during processing. The mounting table 14 is a mounting table (elevator) on which a cassette capable of accommodating a plurality of workpieces is mounted, and is configured to be movable in the vertical direction.

When a box accommodating a workpiece is placed on the loading table 14 , the cutting device 2 unloads the workpiece from the box, and places the workpiece on the holding table 12 through a predetermined transport mechanism. And, the holding table 12 is subjected to a negative pressure from a suction source not shown in the figure, and the workpiece is sucked and held on the holding table 12 .

Here, a more detailed structure of the cutting unit 10 will be described using FIG. 2 . FIG. 2 is an exploded view schematically illustrating the structure of the cutting unit 10 . As shown in FIG. 2 , the cutting unit 10 includes, for example, a spindle housing 16 such as a moving mechanism (not shown) fixed to the cutting device 2 . Inside the main shaft case 16, a main shaft 18 extending in the front-rear direction (Y-axis direction) is rotatably supported. The tip end (tip end) of the main shaft 18 protrudes forward from the main shaft housing 16 .

An opening 18a is formed at the tip end of the main shaft 18, and a spiral valley is provided on an inner wall surface 18b of the opening 18a. A rear flange 20 formed of a material including a ferromagnetic material is attached to the tip end portion of the main shaft 18 . The rear flange 20 includes a flange portion 22 extending radially outward, and a convex portion 24 protruding forward from the surface (front surface) of the flange portion 22 .

In the center of the flange portion 22, an opening 22a is formed to pass through the flange portion 22 front and rear. In addition, on the back (rear) side of the flange portion 22, a tie-shaped It is a fitting portion (not shown) into which the tip end of the main shaft 18 can be fitted. The fitting portion is provided at a position corresponding to the opening 22a.

The rear flange 20 is fixed to the main shaft 18 when the fixing bolt 26 is locked into the opening 22 a and the opening 18 a with the front end of the main shaft 18 fitted into the fitting part formed on the flange part 22 . In addition, on the outer peripheral surface 26a of the fixing bolt 26, a crest corresponding to the trough of the opening 18a is provided.

The surface on the outer peripheral side of the flange portion 22 is a contact surface 22 b that contacts the back side surface of the metal saw 28 . The contact surface 22b is formed in an annular shape when viewed from the axial center direction (Y-axis direction) of the main shaft 18 . The convex portion 24 is formed in a cylindrical shape, and a spiral crest is provided on the outer peripheral surface 24a.

In the center of the metal saw 28 , a circular opening 28 a through which the protrusion 24 is inserted is formed, and the protrusion 24 is inserted through the opening 28 a so that the metal saw 28 is mounted on the rear flange 20 .

In the state where the metal saw 28 is attached to the rear flange 20 , an annular front flange 30 is mounted on the front side of the metal saw 28 . In the center of the front flange 30, an opening 30a is formed, and the protrusion 24 of the rear flange 20 is fitted into the opening 30a. In addition, the back surface on the outer peripheral side of the front flange 30 is a contact surface (not shown) that contacts the front side surface of the metal saw 28 . This contact surface is provided at a position corresponding to the contact surface 22 b of the rear flange 20 .

After the front flange 30 is assembled, the ring-shaped fixing nut 32 is locked to the top end of the protrusion 24 . Thereby, the front flange 30 is pressed to the side of the rear flange 20 , and the metal saw 28 is clamped by the rear flange 20 and the front flange 30 . In addition, an opening 32a is formed in the fixing nut 32, and a trough is provided on an inner wall surface 32b of the opening 32a.

On the front surface of the main shaft case 16, a blade cover 34 for accommodating the metal saw 28 and the like mounted on the main shaft 18 is provided. The knife cover 34 is composed of a knife cover main body 36 fixed to the front surface of the spindle housing 16 and a slide cover 38 slidable in the left-right direction (X-axis direction) relative to the knife cover main body 36 .

The slide cover 38 is connected to the knife cover main body 36 via the cylinder 40 so as to slide by the air supplied from the connection tool 42 . After assembling the metal saw 28 on the main shaft 18 , slide the sliding cover 38 to close the knife cover 34 , so that the metal saw 28 can be accommodated inside the knife cover 34 .

A pair of substantially L-shaped nozzles 44 sandwiching the lower portion of the metal saw 28 front and rear are fixed to the slide cover 38 . Cutting water is supplied to the nozzle 44 via the coupling 46 provided on the slide cover 38 . A plurality of slits (not shown) are formed on the tip side of the nozzle 44 so as to face the metal saw 28 . Cutting water is supplied through the plurality of slits.

On the other hand, a supply hole (not shown) for supplying cutting water to the metal saw 28 is provided in the blade cover main body 36 . The supply hole is connected to the connecting tool 48 provided on the knife cover main body 36, and the metal saw 28 is cooled and cleaned through the cutting water supplied from the supply hole through the connecting tool 48.

Next, the structure of the metal saw 28 is demonstrated using FIG. 3(A) - FIG. 3(C). FIG. 3(A) is a schematic diagram of the metal saw viewed from the side, and FIGS. 3(B) and 3(C) are diagrams schematically illustrating a cross-sectional structure of the metal saw in the thickness direction.

As shown in FIG. 3(A), in the center of the metal saw 28, a circular opening 28a through which the above-mentioned protrusion 24 is inserted is formed. On the outer periphery of the metal saw 28, a saw blade 28b is formed. When the main shaft 18 of the cutting unit 10 rotates, the metal saw 28 attached to the cutting unit 10 rotates along with the rotation. rotating metal When the tip of the saw 28 reaches the workpiece, the workpiece is cut through the saw blade 28b.

The saw blade 28b has a plurality of cutting edge portions (rake surfaces) 28c, and a plurality of back portions (flank surfaces) 28d on the rear side of each of the plurality of cutting edge portions 28c in the rotation direction of the metal saw 28. Each cutting edge portion 28c has a shape protruding toward the outer peripheral direction of the metal saw 28 than the adjacent back portion 28d, and cuts a workpiece. Each back portion 28d has a shape cut in toward the center of the metal saw 28 than the adjacent cutting edge portion 28c, and ensures a space for effectively discharging chips generated by cutting.

FIG. 3(B) is a schematic diagram showing the cross-sectional structure of the metal saw 28 shown in FIG. 3(A) when it is cut perpendicular to the side surface and passes through the dot-dash line AA ' . Fig. 3(B) is a diagram including the cutting edge portion 28c of the saw blade 28b. FIG. 3(C) is a schematic diagram showing the cross-sectional structure when the metal saw 28 shown in FIG. 3(A) is cut perpendicular to the side and passing through the dot-dash line BB ' . FIG. 3(C) is a view of saw blade 28b, particularly including back portion 28d.

As shown in FIG. 3(B) and FIG. 3(C), the metal saw 28 has a first plate-shaped object 50a, a third plate-shaped object 50c, and the first plate-shaped object 50a and the third plate-shaped object 50c. The sandwiched second plate-like object 50b. As shown in FIG. 3(B), the cutting edge portion 28c is composed of a first plate 50a, a second plate 50b, and a third plate 50c. On the other hand, as shown in FIG. 3(C), the back portion 28d is formed by the second plate 50b.

A method of forming the metal saw 28 will be described. First, metal powder is placed in a ring-shaped molding die, and cold-pressed to form a ring-shaped green compact. Next, three ring-shaped green compacts are laminated and fired. to be integrated. The edge grinding process is performed on the outer peripheral part of the obtained sintered body, that is, the metal saw 28 is formed.

The saw blade 28b of the formed metal saw 28 has a cutting edge portion 28c formed of the first to third plate-shaped objects, and a back portion 28d formed of the second plate-shaped object, and the metal saw 28 has a complicated structure. . However, the metal saw 28 according to this embodiment can be manufactured by changing the shape of each plate in this way and then sintering it. Therefore, complex processing is not required to manufacture the metal saw 28 .

For example, when the shape of the metal saw 28 is to be formed from a single plate, in order to form the shape of the back portion 28d, it is necessary to cut out the individual back portion 28d, which takes time and effort. On the other hand, it does not take such labor to form the metal saw 28 according to this embodiment. Therefore, the metal saw 28 including the cutting edge portion 28c, the back portion 28d having a thickness different from that of the cutting edge portion 28c, and the saw blade 28b can be manufactured with cost suppressed.

In addition, when manufacturing the first to third plate-shaped objects, the physical properties of the individual plate-shaped objects can be adjusted by adjusting the constituent material, composition, etc. of the metal powder as the individual raw material. By adjusting the physical properties of the first to third plate-like objects, the physical properties of the sintered metal saw 28 can be adjusted.

For example, in the metal saw 28 related to this embodiment, by adjusting the physical properties of the first to third plate-shaped objects, the rigidity of the first plate-shaped object 50a and the rigidity of the third plate-shaped object 50c can be respectively higher than those of the second plate-shaped object. 50b has high rigidity.

In general, when cutting with a metal saw repeatedly, the corners at both ends in the thickness direction are worn away at the cutting edge of the saw blade, and the corners of the saw blade 28b on the outer periphery of the metal saw tend to be gradually rounded. .

Therefore, the metal saw 28 related to this embodiment is based on The constituent materials, composition, etc. of the first to third plate-shaped objects are adjusted so that the rigidity of the first plate-shaped object 50a and the third plate-shaped object 50c is higher than the rigidity of the inner second plate-shaped object 50b. In this way, the two side surfaces of the metal saw 28 are made into highly rigid plates, so the wear resistance of the metal saw 28 is improved. For this reason, the shape of the metal saw 28 is not likely to change due to abrasion, and the shape of the side surface of the chip capacitor formed by cutting with the metal saw 28 is not easy to become abnormal.

In addition, generally speaking, when the rigidity of the metal saw increases, the hardness tends to increase while the metal saw tends to become brittle, and the possibility of damage due to impact or the like increases. For this reason, only increasing the hardness of the metal saw in order to realize a metal saw excellent in wear resistance causes a problem of impact resistance.

Therefore, in the metal saw 28 related to this embodiment, the toughness of the second plate-shaped object 50b sandwiched by the first plate-shaped object 50a, the third plate-shaped object 50c, and the second plate-shaped object 50b is adjusted to be high. material, composition, etc. The plate with high toughness improves the impact resistance and alleviates the impact received from the outside.

If the toughness of the second plate-shaped object 50b is higher than that of the first and third plate-shaped objects, when an impact is applied to the metal saw 28 from the outside, the second plate-shaped object 50b cushions the impact. In this way, it is possible to prevent damage to the highly rigid first plate-shaped object and third plate-shaped object due to the impact. The second plate 50b has high toughness and low wear resistance, so it is easy to wear when repeatedly cutting with the metal saw 28, but the second plate 50b is not at the two ends where abrasion is particularly prone to occur, so it is durable for a long time usage of.

That is, the metal saw 28 related to this embodiment is equipped with the first plate-shaped object 50a and the third plate-shaped object 50c on the side that is easy to wear, so the saw Changes in shape due to abrasion of the side surfaces of the blade 28b are suppressed. On the other hand, since the second plate-shaped object 50b having high toughness is provided inside, even if a shock is applied to the metal saw 28, occurrence of damage or the like is suppressed. For this reason, the metal saw 28 is extended in life.

The rigidity and toughness of the plate are adjusted according to the constituent elements of the plate and their ratio (content ratio), etc. Furthermore, for example, the constituent elements and their content ratios of the first plate-shaped object are different from those of the second plate-shaped object and their respective ratios, thereby adjusting individual rigidity and toughness. In terms of the plates used in the metal saw 28, although tungsten carbide (tungsten carbide) is used as a binder mixed with cobalt, for example, the rigidity and toughness of the plates can be adjusted through the content of cobalt.

More specifically, when forming a highly rigid plate-like object, the ratio of cobalt contained in tungsten carbide is set to about 5 wt%. In addition, in the case of forming a plate with high toughness, the ratio of cobalt contained in tungsten carbide is about 30 wt%. However, the metal saw system related to this embodiment is not limited to this. Rigidity and toughness are determined together with the thickness of each plate-shaped object according to the desired properties of the metal saw and also according to the type of object to be processed.

In addition, in the metal saw according to this embodiment, a hard abrasive (particle) made of a material such as diamond or alumina is mixed into the first plate-shaped object and the third plate-shaped object. When the grinding material (particles) is mixed into the first plate-shaped object and the third plate-shaped object, the wear resistance is improved compared with other materials constituting each plate-shaped object. When the first plate-like object and the third plate-like object on both sides of the metal saw are mixed with the grinding material (particles), the abrasion of the metal saw can be reduced and the life of the metal saw can be improved. However, the metal saw related to this embodiment is not limited to the case where a sharpener is included.

In addition, in the saw blade 28b of the metal saw 28 according to the present embodiment, the cutting edge portion 28c is composed of the first to third plate-like objects, and a sufficient thickness of the portion to be cut can be ensured. On the other hand, in the back portion 28d, there are no first plate-shaped object 50a and third plate-shaped object 50c on the side surface of the saw blade 28b, so it is possible to ensure effective removal of cutting chips generated from the workpiece. Space.

In addition, this invention is not limited to description of said embodiment, It can change variously and can implement. For example, in the above-mentioned embodiment, the case where there are three plate-shaped objects constituting the metal saw is mainly described. However, it is also possible to configure the metal saw with four or more plates. In this case, the rigidity of the plates on both sides of the metal saw may be higher than the rigidity of the inner plates.

Next, another aspect of the metal saw related to one aspect of the present invention will be described. The structure of the metal saw 28 related to another embodiment is demonstrated using FIG. 4(A) - FIG. 4(C). FIG. 4(A) is a schematic view of the metal saw viewed from the side, and FIGS. 4(B) and 4(C) are diagrams schematically illustrating the cross-sectional structure of the metal saw in the thickness direction. The metal saw 28 related to other embodiments described below is different from the metal saw 28 related to the above-mentioned embodiment in the cross-sectional structure of the main back portion 28d.

FIG. 4(B) is a schematic diagram showing the cross-sectional structure of the metal saw 28 shown in FIG. 4(A) when it is cut perpendicular to the side by the dotted line AA ' . Fig. 4(B) is a diagram including the cutting edge portion 28c of the saw blade 28b. FIG. 4(C) is a schematic diagram showing the cross-sectional structure when the metal saw 28 shown in FIG. 4(A) is cut perpendicular to the side and passing through the dot-dash line BB ' . FIG. 3(C) is a view of saw blade 28b, particularly including back portion 28d.

As shown in Fig. 4 (B) and Fig. 4 (C), the metal saw 28 has a first plate 50a, a third plate 50c, and is covered by the first plate 50a and the third plate 50c. The sandwiched second plate-like object 50b. As shown in FIG. 4(B), the cutting edge portion 28c is composed of a first plate 50a, a second plate 50b, and a third plate 50c. On the other hand, as shown in FIG. 4(C), the back portion 28d is composed of a first plate 50a and a third plate 50c.

A method of forming metal saw 28 related to another embodiment will be described. First, metal powder is placed in a ring-shaped molding die, and cold-pressed to form a ring-shaped green compact. Next, it is temporarily sintered at a low temperature (for example, 500° C.), and processed so as to have a predetermined thickness and shape, thereby forming each plate-shaped object. The 1st plate-like object 50a and the 3rd plate-shaped object 50c are formed in the shape which comprises the cutting edge part 28c and the back part 28d, and the 2nd plate-shaped object 50b is formed in the shape which comprises the cutting edge part 28c.

Next, the formed plates are laminated and sintered (for example, at 900° C.) to integrate them. Sintering is carried out in a state where the first to third plate-shaped objects are clamped between two carbon plates at a predetermined pressure. In addition, in these two carbon plates, protrusions are formed in advance in regions contacting the back portion 28d of the saw blade 28b.

In this way, the first plate-shaped object 50a and the third plate-shaped object 50c, which are softened by exposure to the high temperature during sintering, are pressed against the convex portion of the carbon plate, and face the inner side of the metal saw 28 in the area contacting the back 28d, respectively. out of shape. For this reason, both are in contact so that the 2nd plate-shaped object 50b may be surrounded by the back part 28d. In other words, the first plate 50a and the third plate 50c connect the second plate 50b at the back 28d. Defects are partially buried and deformed. Then, the edge grinding process is performed on the outer peripheral portion of the obtained sintered body, that is, the metal saw 28 is formed.

The saw blade 28b of the formed metal saw 28 has a cutting edge portion 28c formed by the first to the third plate, and a back portion 28d formed by the first plate and the third plate. The 28 series has a complicated structure. However, according to this other embodiment, the metal saw 28 with such a complicated structure can be manufactured easily. In addition, in the metal saw 28 according to this other embodiment, the back portion 28d is formed of a highly rigid plate-like object compared to the metal saw 28 according to the above-mentioned embodiment, so the rigidity of the back portion 28d is increased.

In addition, the back portion 28d may be constituted by at least one of the first plate-shaped object and the third plate-shaped object. That is, it may be constituted by only one of the first plate-shaped object and the third plate-shaped object, or may be constituted by both the first plate-shaped object and the third plate-shaped object.

In addition, the structures, methods, and the like related to the above-mentioned embodiments can be appropriately changed and implemented as long as they do not depart from the scope of the purpose of the present invention.

28: Metal Saw

28a: opening

28b: saw blade

28c: cutting edge

28d: back

50a: the first plate

50b: the second plate

50c: the third plate

52a: Opening of the first plate

52b: Opening of the second plate

52c: Opening of the third plate

Claims (5)

A metal saw having a blade formed on the outer periphery thereof, It integrally has a first plate, a third plate, and a second plate between the first plate and the third plate, and the saw blade has: A plurality of cutting blades formed by the first plate, the second plate, and the third plate; A plurality of back portions formed by the first plate-shaped object or the third plate-shaped object on the rear side of each of the plurality of cutting edge portions in the rotation direction of the metal saw. A metal saw having a blade formed on the outer periphery thereof, It integrally has a first plate, a third plate, and a second plate between the first plate and the third plate, and the saw blade has: A plurality of cutting blades formed by the first plate, the second plate, and the third plate; a plurality of backs formed by the first plate or the third plate on the rear side of each of the plurality of cutting blades in the direction of rotation of the metal saw; The first plate-shaped object and the third plate-shaped object are higher in rigidity than the second plate-shaped object. A metal saw having a blade formed on the outer periphery thereof, The metal saw integrally has a first plate-shaped object, a third plate-shaped object, and a second plate-shaped object between the first plate-shaped object and the third plate-shaped object, The saw blade has: A plurality of cutting blades formed by the first plate, the second plate, and the third plate; Rearward in the direction of rotation of each of the plurality of cutting edge portions of the metal saw a plurality of backs formed by the first plate or the third plate; The first plate-shaped object and the third plate-shaped object are higher in rigidity than the second plate-shaped object, The second plate-shaped object has higher toughness than the first plate-shaped object and the third plate-shaped object. The metal saw according to any one of claim items 1 to 3, wherein, The aforementioned first plate-shaped object and the aforementioned third plate-shaped object have a whetstone. The metal saw according to any one of claim items 1 to 3, wherein, The constituent elements and their ratios of the first plate-shaped object are different from the constituent elements and their ratios of the second plate-shaped object.

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