摘要:
Structure of a cross universal joint is achieved in which the fact that an excessive torque was applied to a universal joint due to a collision accident or mishandling can be easily determined afterwards. Protrusions 20, which are straight lines as seen from the outside surface sides of linking arm sections 15c of a yoke 12c, are formed on the outside surfaces of the linking arm sections 15c. When an excessive torque acts and the linking arm sections 15c are plastically deformed, the protrusions 20 change from a straight line to a non-straight line. From this change it is possible to easily confirm that an excessive torque has been applied to a cross universal joint that includes this yoke 12c. Moreover, when the space between the inside surfaces of the linking arm sections 15c is taken to be D, and the length in the axial direction of the linking arm sections 15c is taken to be L, the dimensions of the parts of the yoke 12c are regulated so that the relation 3
摘要:
A construction is adopted in which an annular spacer 27 is held between first and second inner races 2a, 2b. An internal clearance in a double-row bearing unit is measured in a middle step of assembling work of a wheel supporting bearing assembly, and in the event that a resultant measured value does not become a proper value, an axial dimension of the spacer 27 is adjusted, so that the internal clearance becomes the proper value. Thereafter, the assembling work is made to continue until the assembling work is completed. A problem which is to be solved by the invention is solved in the way described above.
摘要:
A spindle motor comprises a hollow shaft 13 having one end formed with a thrust plate 15, and a sleeve 12 provided to face the shaft 13 through a radial fluid bearing clearance R therebetween, wherein a thrust fluid bearing S is formed between the opposite flat surfaces 15s of the thrust plate 15 and the sleeve 12 facing the flat surfaces 15s. In addition, the hollow shaft 13 has a connection portion 30 at the lower end formed in a concave shape, such that the thrust plate 15 is guided by the inner peripheral surface of the connection portion 30 such that it is coaxial with the shaft 15, and fixed to the shaft 13 by fitting the cylindrical portion 20b of a set screw 20 to the through hole 15b of the thrust plate 15 and the connection portion 30.
摘要:
A cylindrical portion formed in the inside end portion of the hub is caulked and spread using a pressing mold assembled to an oscillating/caulking apparatus to thereby form the caulking portion. In working or forming the caulking portion, a cylindrical projecting portion formed in the central portion of the leading end face of the pressing mold is inserted into the cylindrical portion to thereby prevent the inside diameter of the cylindrical portion from reducing excessively.
摘要:
When an inner ring 3 of a driving-wheel supporting hub unit is fixed to a hub 2, a pressing die 24 is displaced downward and an annular working surface 27 at a lower end surface of the pressing die 24 is pressed against a front end of a cylindrical portion 13a over its whole periphery. Further, in this state, the pressing die 24 is pressed downward toward the hub 2 without rocking the pressing die 24 relative to the hub 2. Thus, the cylindrical portion 13a is plastically deformed radially outward along the working surface 27 simultaneously over its whole periphery. By adopting this method, the operation of plastically deforming the cylindrical portion 13a at the inner end of the hub 2 to form a caulking portion, can be easily and performed accurately. Accordingly, the structure of the caulking portion forming apparatus 21 can be simplified.
摘要:
In a manufacturing method and a manufacturing apparatus for a wheel-support rolling bearing unit, when forming a crimped portion 14 on an end (inside end) of a hub main body 8a, by rocking die forging using a die 26, while preventing enlargement of equipment, in order to prevent forming indentations in a second outer raceway 6a and a second inner raceway 12a, in the present invention, the outer ring 1a is turned by a motor 48, and the balls 32 are rotated. A difference is provided between the rotation speed of the balls 32 and an oscillation speed of the die 26. This difference is preferably at least 10 min−1. By rotating the balls 32 the formation of indentations in the second outer raceway 6a and the second inner raceway 12a is prevented. Moreover, by providing the difference between the rotation speed and the oscillation speed of the die 26, an increase in the torque required for rotation the outer ring 1a is suppressed.
摘要:
When a shape of the cylindrical portion (8b) to be formed into the calking portion (9b) is devised and when a sectional shape of the annular recess portion (23) of the die (15a) for plastically deforming the cylindrical portion (8b) is devised, the calking portion (9b) is continuously given a compressive average stress during the process of working.
摘要:
When an inner ring of a driving-wheel supporting hub unit is fixed to a hub, a pressing die is displaced downward and an annular working surface at a lower end surface of the pressing die is pressed against a front end of a cylindrical portion over its whole periphery. Further, in this state, the pressing die is pressed downward toward the hub without rocking the pressing die relative to the hub. Thus, the cylindrical portion is plastically deformed radially outward along the working surface simultaneously over its whole periphery. By adopting this method, the operation of plastically deforming the cylindrical portion at the inner end of the hub to form a caulking portion, can be easily and performed accurately. Accordingly, the structure of the caulking portion forming apparatus can be simplified.
摘要:
A rolling bearing unit for a drive wheel comprises a hub and a double row rolling bearing thereon. The hub has a first inner ring raceway formed on an inner ring element integrally or separately formed with the hub in an intermediate portion, and a fit cylindrical surface section in a part closer to the inner end of the outer peripheral surface. A separate inner ring having a second inner ring raceway is fitted on the hub, with the axially inner end surface pressed by a caulking portion formed by plastically deforming a cylindrical section formed in the axially inner end portion of the hub in a state that the inner ring is fitted on the fit cylindrical surface section, to be fixed to the hub.
摘要:
In a manufacturing method and a manufacturing apparatus for a wheel-support rolling bearing unit, when forming a crimped portion 14 on an end (inside end) of a hub main body 8a, by rocking die forging using a die 26, while preventing enlargement of equipment, in order to prevent forming indentations in a second outer raceway 6a and a second inner raceway 12a, in the present invention, the outer ring 1a is turned by a motor 48, and the balls 32 are rotated. A difference is provided between the rotation speed of the balls 32 and an oscillation speed of the die 26. This difference is preferably at least 10 min−1. By rotating the balls 32 the formation of indentations in the second outer raceway 6a and the second inner raceway 12a is prevented. Moreover, by providing the difference between the rotation speed and the oscillation speed of the die 26, an increase in the torque required for rotation the outer ring 1a is suppressed.