Abstract: A method of manufacturing a drawn cup needle roller bearing having a seal ring, including forming the seal ring by a press working by: punching a metal plate to form an annular first intermediate material; subjecting the first intermediate material to burring working such that a portion close to an inner diameter of the first intermediate material is bent in an axial direction at a right angle to form an annular second intermediate material having an L-shaped cross section, the second intermediate material comprising a cylindrical portion and an outward flange portion which is bent radially outward from an axial end portion of the cylindrical portion; removing the outward flange portion to form a cylindrical third intermediate; and subjecting the third intermediate material to cold rolling working to regulate an inner diameter, an outer diameter and a cross sectional shape of the third intermediate material.

Abstract: A method forms a concave constituting a ball return passage directly on an inner circumferential surface of a nut blank by plastic working without damaging a die. Letter S shaped concaves are formed on an inner circumferential surface of a nut blank, by pressing by use of a die having a blank holder, a cam driver, cam sliders, and a cylindrical member. The cam driver has inclined surfaces having the same angle of inclination as the cam sliders. The cam sliders have letter S shaped convexes corresponding to the letter S shaped concaves, and are held by through holes, respectively. When the cam driver is pressed from the top thereof, the cam sliders move outwardly in the radial direction, respectively, and the letter S shaped convexes push the inner circumferential surface of the nut blank for plastic deformation.

Abstract: This invention provided a manufacturing method to process a small-diameter step section 18 on an inside end section of a hub body 13a that comprises an outward facing flange 15 and a positioning cylinder 16 stably and with high precision. In this invention, an intermediate material 40 is pressed between a lower punch 36 and an upper punch 46 with an outer peripheral surface of the intermediate material 40 being held by a lower die 37 and an upper die 43, and then a part of the intermediate material 40 is pressed into the lower punch 36 such that the small-diameter step section 18 is formed by cold plastic working.

Abstract: A method forms a concave constituting a ball return passage directly on an inner circumferential surface of a nut blank by plastic working without damaging a die. Letter S shaped concaves are formed on an inner circumferential surface of a nut blank, by pressing by use of a die having a blank holder, a cam driver, cam sliders, and a cylindrical member. The cam driver has inclined surfaces having the same angle of inclination as the cam sliders. The cam sliders have letter S shaped convexes corresponding to the letter S shaped concaves, and are held by through holes, respectively. When the cam driver is pressed from the top thereof, the cam sliders move outwardly in the radial direction, respectively, and the letter S shaped convexes push the inner circumferential surface of the nut blank for plastic deformation.

Abstract: A method of manufacturing a drawn cup needle roller bearing having a seal ring, including forming the seal ring by a press working by: punching a metal plate to form an annular first intermediate material; subjecting the first intermediate material to burring working such that a portion close to an inner diameter of the first intermediate material is bent in an axial direction at a right angle to form an annular second intermediate material having an L-shaped cross section, the second intermediate material comprising a cylindrical portion and an outward flange portion which is bent radially outward from an axial end portion of the cylindrical portion; removing the outward flange portion to form a cylindrical third intermediate; and subjecting the third intermediate material to cold rolling working to regulate an inner diameter, an outer diameter and a cross sectional shape of the third intermediate material.

Abstract: A drawn cup needle roller bearing 30 having a seal ring comprises: a shell 31 having a raceway surface 31a on an inner circumferential face and also having inward flange portions 31b, 31c in both end portions; a cage 32 having a plurality of pockets 32a in a circumferential direction and worked by cutting; a plurality of needles 33 retained in the pockets 32a so that the needles freely rotate along the raceway surface 31a; and a seal ring 34, the shape of which is cylindrical, arranged inside the shell 31 between an end face 32b of the cage 32 and the inward flange portion 31b. The seal ring 34 composes a floating seal and is formed by press working. Due to the foregoing, an excellent dimensional accuracy can be provided and a quantity of lubricant passing through the bearing can be controlled.

Abstract: When a punch is downwardly pressed, an inner circumferential surface of a first rack blank bites into a top surface of a second rack blank. A blank material upwardly flows due to a reaction force and is used to form rack teeth. Thus, a filling degree of the teeth with the material is enhanced. At the time when the forming of the rack teeth is finished, a gap is left between the inner circumferential surface of the first rack blank and the outer circumferential surface of the second rack blank. Thus, a die is not put into a sealed condition. Consequently, a forming load is small so that the lifetime of the die is lengthened. Also, the top surface of the second rack blank bites into a bore hole portion of the first rack blank so that the first rack blank and the second rack blank are joined together. Accordingly, the rigidity of the entire rack teeth is increased.

Abstract: A drawn cup needle roller bearing 30 having a seal ring comprises: a shell 31 having a raceway surface 31a on an inner circumferential face and also having inward flange portions 31b, 31c in both end portions; a cage 32 having a plurality of pockets 32a in a circumferential direction and worked by cutting; a plurality of needles 33 retained in the pockets 32a so that the needles freely rotate along the raceway surface 31a; and a seal ring 34, the shape of which is cylindrical, arranged inside the shell 31 between an end face 32b of the cage 32 and the inward flange portion 31b. The seal ring 34 composes a floating seal and is formed by press working. Due to the foregoing, an excellent dimensional accuracy can be provided and a quantity of lubricant passing through the bearing can be controlled.

Abstract: This invention provided a manufacturing method to process a small-diameter step section 18 on an inside end section of a hub body 13a that comprises an outward facing flange 15 and a positioning cylinder 16 stably and with high precision. In this invention, an intermediate material 40 is pressed between a lower punch 36 and an upper punch 46 with an outer peripheral surface of the intermediate material 40 being held by a lower die 37 and an upper die 43, and then a part of the intermediate material 40 is pressed into the lower punch 36 such that the small-diameter step section 18 is formed by cold plastic working.

Abstract: When a punch is downwardly pressed, an inner circumferential surface of a first rack blank bites into a top surface of a second rack blank. A blank material upwardly flows due to a reaction force and is used to form rack teeth. Thus, a filling degree of the teeth with the material is enhanced. At the time when the forming of the rack teeth is finished, a gap is left between the inner circumferential surface of the first rack blank and the outer circumferential surface of the second rack blank. Thus, a die is not put into a sealed condition. Consequently, a forming load is small so that the lifetime of the die is lengthened. Also, the top surface of the second rack blank bites into a bore hole portion of the first rack blank so that the first rack blank and the second rack blank are joined together. Accordingly, the rigidity of the entire rack teeth is increased.

Abstract: There is provided a bearing unit including one raceway ring 2 which is mounted on a vehicle body, the other raceway ring 4 which is disposed to face the one raceway ring 2 and is mounted on a wheel, and a plurality of rolling elements 6, 8 which are built in rollably between an outer ring raceway 2s and an inner ring raceway 4s which are formed continuously on facing surfaces of both the raceway rings 2, 4, respectively, along a circumferential direction, at least either of the raceway rings 2, 4 having a connecting flange 12a or a mounting flange 12a at which the raceway ring is mounted on the vehicle body or the wheel, wherein both the raceway rings 2, 4 are formed entirely through cold forging with no machining given to a surface of the flange 2a, 12a, while a quenching and tempering treatment by electromagnetic induction and grinding are given to at least the outer ring raceway 2s and the outer ring raceway 4s.

Abstract: A cage element 18 in which pillar element portions 17, 17 are made to project from a rim portion 11 is manufactured by performing a punching process and a bending process on a metal plate. With rim portions 11, 11 of a pair of cage elements 18, 18 disposed concentrically with each other and phases in a circumferential direction of the respective pillar element portions 17, 17 made to coincide with each other, distal ends of the respective pillar element portions 17, 17 are butted to each other to be welded together, whereby respective pillar portions are made. The roundness of the respective rim portions 11, 11 and the shape accuracy and interval accuracy of these respective pillar portions are improved without performing troublesome processes, so as to solve the problem.

Abstract: A manufacturing method of a raceway ring for a radial ball bearing, the radial ball bearing has the raceway ring has at least one of an outer ring formed with an outer ring raceway, of which sectional shape is arcuate, and which is formed entire of circumference on an axially intermediate portion of an inner circumferential face as a raceway surface; and an inner ring formed with an inner ring raceway, of which sectional shape is arcuate, and which is formed entire of circumference on an axially intermediate portion of an outer circumferential face as the raceway surface and plurality of balls rollably provided between the inner ring raceway and the outer ring raceway.

Abstract: A race member in a hub unit for supporting a wheel. The race member includes a cylinder portion, a flange portion bend radially outward from the cylinder portion, and a continuous portion that integrally connects the cylinder portion with the flange portion. The race member is integrally formed by subjecting a metal plate to punching and cold plastic working. The continuous portion is larger in thickness than the metal plate.

Abstract: A race member in a hub unit for supporting a wheel. The race member includes a cylinder portion, a flange portion bend radially outward from the cylinder portion, and a continuous portion that integrally connects the cylinder portion with the flange portion. The race member is integrally formed by subjecting a metal plate to punching and cold plastic working. The continuous portion is larger in thickness than the metal plate.

Abstract: A systen for making covering masks used for the photoengraving process comprising a hard copy unit for preparing a hard copy on which negative images are printed while being enlarged to a certain magnification, a tabulator unit for inputting coordinates data which represents the outline of a predetermined image on the hard copy, a processing unit for processing the coordinates data inputted and outputting an instruction about the outline of the predetermined image which has been reduced to a value equal to the certain magnification, and a cutter-provied plotter unit for cutting the light shielding layer of a stripping film responsive to the instruction outputted from the processing unit.