Abstract: A drilling tip includes a tip main body that has a posterior end portion having a columnar or disk shape centered on a tip center line and a distal end portion and is made of a cemented carbide and a hard layer that coats the distal end portion and is made of a polycrystalline diamond sintered body. The distal end portion has a convex portion, and a concave portion. A diameter D of the posterior end portion is 8 mm to 20 mm. A ratio r1/D of a radius r1 of the convex portion is 0.1 to 0.65, and a ratio r2/D of a radius r2 of the concave portion is 0.05 to 3.0. An angle formed by a straight line that connects a tangent point which the convex portion tangents to the concave portion and a center of the convex portion to each other is 20° to 90°.

Abstract: A drilling tip includes a tip main body that has a posterior end portion having a columnar or disk shape centered on a tip center line and a distal end portion and is made of a cemented carbide and a hard layer that coats the distal end portion and is made of a polycrystalline diamond sintered body. The distal end portion has a convex portion, and a concave portion. A diameter D of the posterior end portion is 8 mm to 20 mm. A ratio r1/D of a radius r1 of the convex portion is 0.1 to 0.65, and a ratio r2/D of a radius r2 of the concave portion is 0.05 to 3.0. An angle formed by a straight line that connects a tangent point which the convex portion tangents to the concave portion and a center of the convex portion to each other is 20° to 90°.

Abstract: A base material for a hard sintered material has a multi-stage columnar shape having a central axis and extending in an axial direction of the central axis. The base material includes a smaller-diameter portion, a larger-diameter portion, a base material end surface located between a one end portion in the axial direction of an outer peripheral surface of the larger-diameter portion and the other end portion in the axial direction of the smaller-diameter portion, and facing toward the one end portion in the axial direction, and a first inclined portion disposed in at least a portion in a circumferential direction of an annular corner portion to which an outer peripheral surface of the larger-diameter portion and the base material end surface are connected. The first inclined portion is located inward in a radial direction toward the one end portion in the axial direction.

Abstract: A base material for a hard sintered body includes a pillar portion having a central axis and extending in the axial direction of the central axis. The pillar portion has a first outer peripheral portion, a second outer peripheral portion, and a protruding stripe portion. In the cross-sectional view, one side portion of the first outer peripheral portion extending in a circumferential direction or a radial direction is located inside the other side portion. In the cross-sectional view, one side portion of the second outer peripheral portion extending in the circumferential direction or the radial direction is located outside the other side portion in the radial direction. The protruding stripe portion is located in a connection portion between the other side portion of the first outer peripheral portion and one side portion of the second outer peripheral portion, and protrudes outward.

Abstract: A polycrystalline diamond sintered material tool includes: a cemented carbide substrate, which is mainly composed of WC and includes Co; and a diamond layer containing a metal catalyst made of Co provided on the cemented carbide substrate. The average layer thickness of a Co rich layer formed in an interface between the cemented carbide substrate and the diamond layer is 30 ?m or less. CMAX/CDIA is 2 or less when CDIA is an average content of Co included in the diamond layer and CMAX is a peak value of a Co content in the Co rich layer. D/DO is less than 2 when D is an average grain size of WC particles in a region from the interface between the cemented carbide substrate and the diamond layer to 50 ?m toward an inside of the cemented carbide substrate; and DO is an average grain size of WC particles.

Abstract: A multistage shaft sealing apparatus includes a first sealing unit, a second sealing unit, and a third sealing unit provided, in a sequential order from a side of the apparatus closer to inside of the apparatus, in a fluid leakage passage formed between the rotating shaft or the rotating member and a housing located to surround the rotating shaft or the rotating member. The first sealing unit includes a first runner and a first sealing ring which form a non-contact-type sealing surface; the second sealing unit includes a second runner and a second sealing ring which form a contact-type sealing surface; the third sealing unit includes a third runner and a third sealing ring which form a contact-type sealing surface, and a purge water supply passage supplying purge water to the third sealing unit and a purge water discharge passage discharging the purge water supplied to the third sealing unit.

Abstract: A drilling tip according to the disclosure has a tip body which is provided with a tip portion tapered toward a tip side of the tip body; and a hard layer which is formed on a surface of the tip portion of the tip body, an outermost layer of the hard layer is a cBN sintered material having 70 to 95 vol % of cBN grains, and when a cross-sectional structure of the outermost layer is observed, a binder phase having a width of 1 nm or greater and 30 nm or less and containing Al, B, and N, and in which a ratio of an O content to an Al content is 0.1 or less exists between neighboring cBN grains.

Abstract: A drill bit insert attached to a tip portion of a drill bit to perform drilling, includes: an insert body (1) that includes: a rear end portion buried in a bit body of the drill bit; and a tip portion protruding from a surface of the drill bit and tapered toward a tip side of the insert body, in which a surface of at least the tip portion of the insert body (1) made of polycrystalline cubic boron nitride compact (4) sintered using a catalytic metal containing Al and at least one selected from the group consisting of Co, Ni, Mn, and Fe and containing 70 vol % to 95 vol % of cubic boron nitride.

Abstract: In a drill bit insert of the present invention, an insert body of the drill bit insert includes: a rear end portion forming a columnar shape or a disk-like shape; an intermediate portion having an outer diameter smaller than that of the rear end portion; and an end portion having an outer diameter from the center line of the insert gradually decreasing toward the tip side, the hard surface layer is coated on the insert body from a surface of the end portion of the insert body to an outer periphery of the intermediate portion, and an outer diameter of the hard surface layer on the intermediate portion is equal to that of the rear end portion.

Abstract: A multistage shaft sealing apparatus includes a first sealing unit, a second sealing unit, and a third sealing unit provided, in a sequential order from a side of the apparatus closer to inside of the apparatus, in a fluid leakage passage formed between the rotating shaft or the rotating member and a housing located to surround the rotating shaft or the rotating member. The first sealing unit includes a first runner and a first sealing ring which form a non-contact-type sealing surface; the second sealing unit includes a second runner and a second sealing ring which form a contact-type sealing surface; the third sealing unit includes a third runner and a third sealing ring which form a contact-type sealing surface, and a purge water supply passage supplying purge water to the third sealing unit and a purge water discharge passage discharging the purge water supplied to the third sealing unit.

Abstract: A rotary cutting tool including a polycrystalline diamond material of the invention includes: a tool body rotated about an axis with a carbide substrate made of cemented carbide and a flute provided at a tip portion thereof; a PCD layer sintered integrally with the carbide substrate, provided on an inside face of the flute facing in a rotation direction; and a cutting edge provided on the PCD layer to have the inside face as a rake face, in which a margin portion continuous with a rear side of the flute in the rotation direction is formed on an outer periphery of the tip portion, the cutting edge is formed at a ridge portion of the rake face, and a thickness of the PCD layer is ? to 1 times a width of the margin portion.

Abstract: A drill bit button insert is attached to a button inserts mounted in a drill bit and performs a drilling. The drill bit button insert includes a tip body and an abrasive layer that is formed of a diamond sintered body harder than the tip body and is coated at least at the button insert working surface of the tip body. The abrasive layer has two or more high hardness layers and a low hardness layer having a hardness lower than that of the high hardness layers disposed between the high hardness layers. The high hardness layers and the low hardness layer are provided from the surface side of the abrasive layer toward the tip body side.

Abstract: The shaft sealing structure includes a seal ring that has abutment portions formed by dividing the seal ring along the axial direction and that is provided around a main shaft in a ring-like manner; a support member that is provided in the seal ring along the circumferential direction of the main shaft; and a thermoswitch that is connected to the support member between the abutment portions and that presses the support member toward the center of the main shaft when the temperature rises to a temperature higher than that during normal operation, in which the seal ring is fixed at a position separated from the main shaft during the normal operation and is moved by the support member toward the center of the main shaft when the temperature rises to a temperature higher than that during the normal operation.

Abstract: A drilling tip according to the disclosure has a tip body which is provided with a tip portion tapered toward a tip side of the tip body; and a hard layer which is formed on a surface of the tip portion of the tip body, an outermost layer of the hard layer is a cBN sintered material having 70 to 95 vol % of cBN grains, and when a cross-sectional structure of the outermost layer is observed, a binder phase having a width of 1 nm or greater and 30 nm or less and containing Al, B, and N, and in which a ratio of an O content to an Al content is 0.1 or less exists between neighboring cBN grains.

Abstract: A polycrystalline diamond sintered material tool includes: a cemented carbide substrate, which is mainly composed of WC and includes Co; and a diamond layer containing a metal catalyst made of Co provided on the cemented carbide substrate. The average layer thickness of a Co rich layer formed in an interface between the cemented carbide substrate and the diamond layer is 30 ?m or less. CMAX/CDIA is 2 or less when CDIA is an average content of Co included in the diamond layer and CMAX is a peak value of a CO content in the Co rich layer. D/DO is less than 2 when D is an average grain size of WC particles in a region from the interface between the cemented carbide substrate and the diamond layer to 50 ?m toward an inside of the cemented carbide substrate; and DO is an average grain size of WC particles.

Abstract: There is provided a method for producing an artificial retina in which an organic dye compound that induces a receptor potential responding to photostimulation is fixed on a polymer sheet substrate, comprising a bonding step of immersing the substrate in a solution containing the organic dye compound to chemically bond the organic dye compound to the substrate; a first washing step of washing with water the substrate to which the organic dye compound has been chemically bonded; and a second washing step of, after the first washing step, washing with an organic solvent the substrate to which the organic dye compound has been chemically bonded. Thus, there can be provided an artificial retina which has excellent mechanical properties such as elongation at break and good biocompatibility, and is capable of inducing a receptor potential responding to photostimulation with high sensitivity.

Abstract: A recording medium processing apparatus includes a housing that accommodates a processing unit, which is capable of processing a recording medium, and that has an internal space a part of which is open; an internal stacker that is disposed in the internal space and that allows the recording medium to be stacked thereon; a light source that is disposed in a part of the internal stacker and that emits a light beam toward a predetermined position on the internal stacker, the light beam notifying a user of a state in which the recording medium is or is not stacked on the internal stacker; and a reflection member that is disposed in a part of the internal stacker and that reflects the light beam from the light source laterally outward from the internal stacker.

Abstract: A polycrystalline tungsten compact, having high density and a fine grain structure is produced by: preparing a raw material powder made of W particles, a raw material powder where W powder and an alloy particle powder of one or more selected from Ti, Zr, Hf, V, Nb, Ta, Cr, Mo and Mn are blended, or a green compact thereof; inserting them in a pressure sintering apparatus; and sintering them in a state where a pressing of 2.55-13 GPa is loaded on the raw material powders or the green compacts at 1200° C. to a melting point. A relative density of the compact is 99% or more, a porosity of the compact measured in an arbitrary cross section of the compact is 0.2 area % or less, an average crystal grain size is 50 ?m or less, and an average aspect ratio of crystal grains is 1 to 2.5.

Abstract: A drill bit insert attached to a tip portion of a drill bit to perform drilling, includes: an insert body (1) that includes: a rear end portion buried in a bit body of the drill bit; and a tip portion protruding from a surface of the drill bit and tapered toward a tip side of the insert body, in which a surface of at least the tip portion of the insert body (1) made of polycrystalline cubic boron nitride compact (4) sintered using a catalytic metal containing Al and at least one selected from the group consisting of Co, Ni, Mn, and Fe and containing 70 vol % to 95 vol % of cubic boron nitride.

Abstract: In a drill bit insert of the present invention, an insert body of the drill bit insert includes: a rear end portion forming a columnar shape or a disk-like shape; an intermediate portion having an outer diameter smaller than that of the rear end portion; and an end portion having an outer diameter from the center line of the insert gradually decreasing toward the tip side, the hard surface layer is coated on the insert body from a surface of the end portion of the insert body to an outer periphery of the intermediate portion, and an outer diameter of the hard surface layer on the intermediate portion is equal to that of the rear end portion.