JP3720922B2 - Method and apparatus for manufacturing double row bearing - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method and an apparatus for manufacturing a double row bearing used for, for example, a hub unit of an automobile.
[0002]
[Prior art and problems to be solved by the invention]
For example, a double row bearing used in a hub unit of an automobile needs to receive a radial load and a thrust load at the same time. Therefore, a double row tapered roller bearing Wa as shown in FIG. Many double row angular contact ball bearings Wb as shown are used.
[0003]
As a method for manufacturing the outer ring or the like of these bearings, a method of forging from a round bar material is known. Conventionally, the outer ring and the inner ring have been forged with different materials, but this has the disadvantage of not only reducing the material yield but also increasing the number of molding steps, resulting in increased costs.
Therefore, there is provided a method of forming a single row outer ring and an inner ring as a set from one material (see, for example, Japanese Patent Application Laid-Open No. 58-107234), but this method uses two formed single row outer rings. A double row outer ring is formed by welding, and not only a welding operation is required, but also a turning process of the outer diameter surface and the end surface to be welded is necessary as a pretreatment for this welding. For this reason, the cost is increased, and variations in the strength of the welded portion are unavoidable, which is unsuitable for bearings used under severe conditions, for example, automotive hub units.
[0004]
Further, it has been proposed to improve the material yield by forming a single row of a double row bearing outer ring and one inner ring combined therewith (see, for example, Japanese Patent Publication No. 5-66215). ).
However, in the above-mentioned Japanese Patent Publication No. 5-66215, in the final step of forming the outer ring material from the outer ring equivalent part, in a die having an outer diameter substantially the same as the final outer diameter of the outer ring, a cylindrical knockout and While pressing the outer ring equivalent part from both ends in the axial direction with a stripper, the inner diameter of the outer ring equivalent part is ironed by upper and lower punches from both ends in the axial direction so as to form a symmetric thick part at the central part in the axial direction. I have to. In this process, the outer ring equivalent portion is pressurized from both ends in the axial direction by the knockout and stripper, so that flow extension is suppressed at both ends of the outer ring equivalent portion. It could not be formed with high accuracy.
[0005]
SUMMARY OF THE INVENTION An object of the present invention is to provide a manufacturing method and apparatus for a double row bearing that is low in manufacturing cost and can form a thick portion of a double row bearing outer ring material with high positional accuracy.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, a method for manufacturing a double row bearing according to claim 1 includes a first step of pressing a round bar material in the axial direction and setting it to an outer diameter substantially the same as the final outer diameter of the outer ring, One of the inner rings combined with the outer ring on the bottom side of the cup molded product is formed by extruding the raw material in one axial direction to form a cup molded product having a portion corresponding to the outer ring having substantially the same depth as the final axial dimension of the outer ring. A second step of simultaneously forming an inner ring equivalent portion corresponding to the above, a third step of punching the bottom portion of the cup molded product in the second step, and a second step of punching and separating the inner ring equivalent portion from the cup molded product after the bottom portion has been punched. The outer ring equivalent part and the die are pressed while pressing the outer ring equivalent part after separation of the four parts and the inner ring equivalent part only from the axial upper end part in the die so as to allow flow extension of the lower end of the outer ring equivalent part. Lubricant trapped between While discharging to the outside, characterized by comprising a fifth step of forming a double row bearing outer ring material with the thick portion of the symmetrical form in the axial direction central portion by ironing the inner diameter from the axial end Is.
[0007]
In the above configuration, the double row bearing outer ring and one inner ring combined therewith are formed as a set from one material, so that the material yield is improved. Further, since the double row bearing outer ring is formed in an integral shape from the beginning, welding or pre-processing does not require turning. Furthermore, the double row bearing outer ring and the one inner ring can be manufactured only by the continuous pressing process. Moreover, in the fifth step, when the inner diameter of the outer ring equivalent portion is ironed from both ends in the axial direction, pressure is applied only from the upper end portion in the axial direction of the outer ring equivalent portion. The meat portion can be formed with high positional accuracy at the axially central portion of the double-row bearing outer ring material.
[0008]
In the method for manufacturing a double row bearing, as described in claim 2, in the second step, a side wall portion of the outer ring corresponding portion adjacent to the inner ring corresponding portion is 2 to 15 ° with respect to the depth direction. In this case, when forming the inner ring from the inner ring equivalent part separated from the outer ring equivalent part, the allowance on the outer diameter side of the separated inner ring equivalent part can be reduced.
[0009]
The manufacturing apparatus of Fukurei bearing of claim 3, wherein the upsetting pressurizes the round bar material axially in cooperation with knockouts in the die with a final outer diameter substantially the same outer diameter of the outer ring upset and upsetting device having a punch, in cooperation with the knockout and the stripper in the die with a final outer diameter substantially the same inner diameter of the outer ring, the upsetting material, extruded in one axial direction, the final axial direction of the outer ring Forming a cup molded product having a portion corresponding to the outer ring having substantially the same depth as the dimensions, and having an extrusion punch and die simultaneously forming an inner ring corresponding portion corresponding to one inner ring combined with the outer ring on the bottom side of the cup molded product. A punching device for punching and separating the inner ring portion of the cup-shaped product from which the bottom is punched, Cylinder that presses in the axial direction only from the upper end in the axial direction of the part corresponding to the outer ring from which the inner ring equivalent part is separated, among the separation device for the inner ring equivalent part having the die and the inner diameter substantially the same as the final outer diameter of the outer ring In cooperation with the cylindrical pressure member, while allowing flow extension at the lower end of the outer ring equivalent part, the outer diameter of the outer ring equivalent part is not changed, and the inner diameter is ironed from both ends in the axial direction to be symmetric with respect to the central part in the axial direction. It has an upper and lower punch for forming a double row bearing outer ring material with a thick part of the type, and when it is pressed from the upper end in the axial direction by the upper punch or pressure member, it is confined between the outer ring equivalent part and the die And a ironing device having a cylindrical stopper for finally positioning a lower end of a portion corresponding to the outer ring that is flow-extended and having a lubricant drain hole provided in the die for allowing the lubricant to flow out to the outside. It is characterized by It is intended.
[0010]
In the said structure, it can use suitably for enforcing the manufacturing method of the double row bearing of Claim 1 or 2. In particular, when ironing the inner diameter of the outer ring portion from both axial ends by upper and lower punches, the cylindrical pressure member presses only from the upper end of the outer ring corresponding portion in the axial direction, and finally the lower end of the outer ring corresponding portion is cylindrical. As a result of allowing the flow extension at the lower end corresponding to the outer ring, the thick wall portion can be formed with high positional accuracy at the center in the axial direction of the double row bearing outer ring material.
[0011]
Further, as in claim 4, it is preferable that the die is elastically supported. In this case, when the outer ring equivalent portion is pressed from above with a pressurizing member while ironing, the die is brought to the outer ring equivalent portion. As a result of lowering and reducing the friction between the die and the outer peripheral surface of the portion corresponding to the outer ring, the thick portion can be formed at a more accurate position in combination with the allowance for flow extension.
[0012]
Further, in the above double row bearing manufacturing apparatus , as described in claim 5 , the pressurization of the pressurizing member with respect to the outer ring equivalent portion is relative only corresponding to the final stage of lowering of the pressurizing member. It has preferred if it is set to be stronger in. This is to prevent the meat from sticking out between the upper punch and the outer ring equivalent portion when pressurized with a strong force from the beginning.
The double row bearing manufacturing apparatus may reduce friction between the outer ring equivalent portion and the die when the outer ring equivalent portion is pressurized in the axial direction. In addition, the die having an inner diameter substantially the same as the final outer diameter of the outer ring is elastically supported, and at the same time, a lubricant interposed between the inner peripheral surface of the die and the outer peripheral surface of the thick portion corresponding to the outer ring is used to lubricate the die. It may be allowed to flow through the agent removal hole. In this case, when ironing the outer ring equivalent part from above with a pressure member, the elastically supported die descends along with the outer ring equivalent part, reducing friction between the die and the outer peripheral surface of the outer ring equivalent part. As a result, the thick portion can be formed at a more accurate position in combination with the allowance for flow extension. In addition, since the lubricant interposed between the inner peripheral surface of the die and the outer peripheral surface of the thick portion corresponding to the outer ring can flow out through the lubricant removal hole of the die, the thick portion is thinned. There is nothing.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a schematic explanatory diagram of the process sequence of the production method of the present invention. With reference to the figure, in the first step, the round bar material W ₁ is a disc element W ₂ having a predetermined outer diameter (for example, an outer diameter substantially the same as the final outer diameter).
[0014]
Next, in the second step, the outer ring equivalent portion W ₄ having a predetermined depth (substantially the same as the final axial direction dimension), the bottom portion W _{3 at} one end in the axial direction, and one inner ring equivalent portion W ₆ is extruded in one axial direction. A cup molded product W ₂ having the following is molded. At this time, in the molded cup product W ₄ , as shown in FIG. 2, the side wall portion continuous to the bottom W ₃ side of the outer ring equivalent portion W ₂ is inclined at a predetermined angle with respect to the axial direction. The inclination angle is preferably 2 to 15 ° in that the allowance for the outer diameter of the inner ring equivalent portion W ₆ can be reduced as compared with the case where the side wall portion is straight. For example, the inclination angle β on the outer diameter side is 9 ° and the inclination angle γ on the inner diameter side is 3 °.
[0015]
Then, in a third step, punching the bottom W _3, in the fourth step, the inner ring portion separating punched W _6.
Then, in the fifth step, as shown in FIG. 3 (f1) ~ (f4) and FIGS. 8 (a) and 8 (b), in the die 19, the cup trunk portion is the outer ring portion W _4, stripper While pressing from the upper end in the axial direction only by the upper punch 22 or the upper punch 22, the inner diameter of the cup body W ₄ is ironed from both ends in the axial direction by the upper and lower punches 22 and 23, and the thick portion is symmetrically formed in the central portion in the axial direction. A double-row bearing outer ring material W ₅ (hereinafter, simply referred to as an outer ring material W ₅ ) is formed. 19a, corresponding to the thick portion a lubricant drain hole formed in the die 19, the lubricant tends to be trapped between the die 19 and the outer ring portion W _4, to flow out to the outside.
[0016]
4 to 8 are schematic longitudinal side views of the apparatus of each step for carrying out the method of FIG. 1, and FIG. The upsetting apparatus A includes a upset punch 12 upsetting the round bar material W ₁ to the disc element W ₂ having a predetermined shape in cooperation with the knockout 11 in the die 10 having a predetermined inner diameter.
FIG. 5 shows a molding apparatus B, which cooperates with the knockout 14 in the die 13 having a predetermined inner diameter to form the disk element W ₂ after installation into a cup molded product W ₂ , and the cup molded product W _2. In order to form one inner ring equivalent portion W ₆ at the same time at the bottom portion W ₃ of the steel plate, it has an extrusion punch 16 having a two-stage shape.
[0017]
FIG. 6 shows a bottom punching device C, which has a bottom punching punch 18 for punching the bottom W ₃ of the cup molded product W _{2 in} a die 17 having a predetermined shape.
FIG. 7 shows an inner ring separating device D having a punch 25 for separating an inner ring corresponding portion W ₆ in a die 24 having a predetermined shape.
8 and (a) (b) shows an ironing forming apparatus E, in the die 19 having a predetermined inside diameter, a pressure member for pressing the upper axial end of the outer ring portion W ₄ of the cup body portion, For example, in cooperation with the cylindrical stripper 21, the inner diameter of the cup body W ₄ is ironed from both ends in the axial direction to form the outer ring material W ₅ having a symmetrical thick portion at the axial center. Upper and lower punches 22 and 23 are provided. The upper punch 22 and the lower punch 23 have a vertically symmetrical shape. FIG. 8A shows a state before starting ironing, and FIG. 8B shows a final state of ironing.
[0018]
In this case, the lower punch 23 is fixed at a fixed position with respect to the base (not shown), the upper punch 22 is supported so as to be movable up and down, and its processing lower end position is accurately set, so that the outer ring material W is set. It is designed to mold ₅ shapes.
A stripper 21 as a pressure member is supported so as to be movable up and down outside the upper punch 22 and is lowered to a fixed position with respect to the base. The pressure applied by the stripper 21 is set to be relatively weak, and the pressure is strongly applied only at the final stage of the lowering. This is because the wall thickness of the upper end portion of the outer ring equivalent portion W ₄ is thin, so that if a pressure is applied with a strong force from the beginning, the meat protrudes into the gap having a triangular cross section with the upper punch 22. This is to prevent it.
[0019]
The knockout 20 as a stopper is fixed to a fixed position of the base together with the lower punch 22, and the lower end position (molding end position) of the outer ring equivalent portion W ₄ is blocked at the fixed position. securing the axial dimension of W _5, and the thick portion by upper and lower punches 22 and 23 are configured to be formed in the axial center portion.
[0020]
The die 19 is movable up and down with respect to the base and is elastically supported by the compression coil spring 26. For this reason, when the outer ring equivalent portion W ₄ is pressed from above by the stripper 21 or the upper punch 22 and descends, the die 19 also slides down as shown in FIGS. And the outer ring equivalent portion W ₄ are reduced in friction. Further, as described above, the die 19 is formed with a lubricant drain hole 19a corresponding to the thick portion.
[0021]
Next, the operation of this embodiment will be described.
The round bar material W ₁ is cut into a fixed size, heated by a heating device (not shown), and sent to the upsetting process. In the upsetting process, as shown in FIG. 4, the knockout 11 and the upsetting punch 12 cooperate in the die 10 to install the round bar material W ₁ into the disc element W ₂ having a predetermined outer diameter.
[0022]
In the molding step, as shown in FIG. 5, the cup shaped article W ₂ which is molded simultaneously one the inner ring portion W ₆ at the bottom W ₃ of the outer ring portion W ₄ is molded. In the bottoming process, as shown in FIG. 6, bottoming is performed, and then the inner ring equivalent portion W ₆ is separated as shown in FIG. 7, and then ironed as shown in FIG. to shape the W _5.
[0023]
The outer ring material W ₅ and the inner ring equivalent portion W ₆ formed in this way are further machined to be finished in a predetermined shape.
In the present embodiment, the double row bearing outer ring and the one inner ring combined therewith are formed from a single material as a set, so that the material yield is improved. Further, since the double row bearing outer ring is formed in an integral shape from the beginning, welding or pre-processing does not require turning. Furthermore, the double row bearing outer ring and the one inner ring can be manufactured only by the continuous pressing process. Therefore, a double row bearing can be manufactured efficiently and at a low cost.
[0024]
Moreover, in the ironing forming step, which is the fifth step, when the inner diameter of the outer ring equivalent portion W ₄ is ironed from both ends in the axial direction, pressure is applied only from the upper end in the axial direction of the outer ring equivalent portion W _{4. 4} the lower end of the flow extension acceptable results, the thick portion can be positioned accurately formed in the axial center portion of the outer race material W _5. In particular, since the final position the lower end of the outer ring portion W ₄ by a cylindrical stopper, it is possible to form a high positional accuracy thick portion.
[0025]
Further, since the bottom side wall portion of the outer ring portion W ₄ during the formation of the cup shaped article W ₂ has an inclination of 2 to 15 ° with respect to the depth direction, inner ring from the cup shaped article W ₂ in separating portions W _6, it is possible to reduce the machining allowance of the outer diameter side of the inner ring portion W _6.
Further, since the die 19 is elastically supported, the friction between the die 19 and the outer ring equivalent portion W ₄ can be reduced when the inner diameter is ironed while pressing the outer ring equivalent portion W ₄ from above. It can be formed at a more accurate position.
[0026]
In addition, when the ironing the outer ring portion W _4, a lubricant interposed between the inner periphery and the outer periphery of the thick portion of the outer ring portion W ₄ of the die 19, the lubricant removal from the die 19 Since it can be made to flow out through the hole 19a, a lack of thickness does not occur in the thick portion.
In the above embodiment, the case of the double row tapered roller bearing is shown, but the same applies to the case of the double row angular contact ball bearing, and the present invention is applicable not only to warm and hot forging but also to cold forging. Applicable.
[0027]
In addition, the present invention is not limited to the above embodiment, and various modifications can be made within the scope of the present invention.
[0028]
【The invention's effect】
According to the method for manufacturing a double row bearing according to claim 1, since the double row bearing outer ring and one inner ring combined therewith are formed from a single material as a set, the material yield is improved. Further, since the double row bearing outer ring is formed in an integral shape from the beginning, welding or pre-processing does not require turning. Furthermore, the double row bearing outer ring and the one inner ring can be manufactured only by the continuous pressing process. Moreover, in the fifth step, when the inner diameter of the outer ring equivalent portion is ironed from both ends in the axial direction, pressure is applied only from the upper end portion in the axial direction of the outer ring equivalent portion. The meat portion can be formed with high positional accuracy at the axially central portion of the outer ring material.
[0029]
According to the method for manufacturing a double row bearing according to claim 2, when forming a cup molded product including the outer ring equivalent portion and the inner ring equivalent portion, the side wall portion of the outer ring equivalent portion adjacent to the inner ring equivalent portion is formed. It has an inclination of 2 to 15 ° with respect to the depth direction. In this case, when forming the inner ring from the inner ring equivalent part separated from the outer ring equivalent part, the allowance on the outer diameter side of the separated inner ring equivalent part can be reduced.
[0030]
According to the double row bearing manufacturing apparatus of the third aspect, the double row bearing manufacturing apparatus according to the first or second aspect can be suitably used for carrying out the double row bearing manufacturing method. In particular, when ironing the inner diameter of the outer ring portion from both axial ends by upper and lower punches, the cylindrical pressure member presses only from the upper end of the outer ring corresponding portion in the axial direction, and finally the lower end of the outer ring corresponding portion is cylindrical. As a result of allowing the flow extension at the lower end corresponding to the outer ring, the thick wall portion can be formed with high positional accuracy at the axially central portion of the outer ring material.
[0031]
Further, according to the double row bearing manufacturing apparatus of claim 4, when the inner diameter is ironed while pressing the outer ring equivalent portion from above, the friction between the die and the outer peripheral surface of the outer ring equivalent portion can be reduced. The thick portion can be formed at a more accurate position.
According to the double row bearing manufacturing apparatus of the fifth aspect, the pressurization of the pressurizing member to the outer ring equivalent portion is set relatively strongly only corresponding to the final stage of the lowering of the pressurizing member. Therefore, it is possible to prevent the meat from protruding between the upper punch and the portion corresponding to the outer ring.
Further, according to the double row bearing manufacturing apparatus of claim 6 , when the inner diameter is ironed while pressing the outer ring equivalent portion from above, the friction between the die and the outer peripheral surface of the outer ring equivalent portion can be reduced. The thick portion can be formed at a more accurate position. Further, when ironing the outer ring equivalent portion, the lubricant interposed between the inner peripheral surface of the die and the outer peripheral surface of the thick portion of the outer ring equivalent portion can flow out through the lubricant removal hole of the die. Therefore, there is no lack of thickness in the thick part.
[Brief description of the drawings]
FIGS. 1A to 1F are schematic views showing a method of manufacturing a double row bearing according to an embodiment of the present invention in the order of steps.
FIG. 2 is an enlarged cross-sectional view of a main part of a cup molded product in a second step.
FIGS. 3 (f-1) to (f-4) are schematic cross-sectional views sequentially showing the ironing process.
FIG. 4 is a schematic sectional view of the upsetting device.
FIG. 5 is a schematic cross-sectional view of a molding apparatus.
FIG. 6 is a schematic sectional view of the bottom removal device.
FIG. 7 is a schematic cross-sectional view of an inner ring separation device.
FIGS. 8A and 8B are schematic cross-sectional views of an iron forming apparatus, in which FIG. 8A shows a state before iron formation, and FIG. 8B shows a state after iron formation.
FIGS. 9A and 9B are schematic cross-sectional views each showing a double row bearing to which the present invention is applied.
[Explanation of symbols]
W Round bar material W ₁ disc element (incorporated material)
W ₂ cup molded product W ₃ bottom part W ₄ outer ring equivalent part W ₅ double row bearing outer ring material W ₆ inner ring equivalent part A upsetting device B forming device C bottoming device D inner ring separating device E ironing device 10, 13, 17, 24 Die 11, 14, 20 Knockout 12 Upsetting punch 15 Stripper 16 Extrusion punch 18 Bottom punch 19 Knockout (stopper)
21 Stripper (Pressure member)
22 Upper punch 23 Lower punch 25 Punching punch

Claims (6)

A first step of pressing the round bar material in the axial direction and setting it to substantially the same outer diameter as the final outer diameter of the outer ring;
The inserted material is extruded to one side in the axial direction to form a cup molded product having a portion corresponding to the outer ring having substantially the same depth as the final axial dimension of the outer ring, and is combined with the outer ring on the bottom side of the cup molded product. A second step of simultaneously forming an inner ring equivalent portion corresponding to the inner ring,
A third step of punching out the bottom of the cup-formed product in the second step;
A fourth step of punching and separating the inner ring equivalent portion from the cup molded product after the bottom portion has been punched;
The outer ring equivalent part after separation of the inner ring equivalent part is confined between the outer ring equivalent part and the die while being pressurized only from the upper end in the axial direction in the die so as to allow flow extension at the lower end of the outer ring equivalent part. A fifth step of forming a double row bearing outer ring material having a symmetrical thick wall portion in the axial central portion by squeezing the inner diameter from both ends in the axial direction while discharging the lubricated lubricant to the outside. A method of manufacturing a double row bearing, characterized in that   2. The double row bearing according to claim 1, wherein, in the second step, a side wall portion of the outer ring corresponding portion adjacent to the inner ring corresponding portion has an inclination of 2 to 15 ° with respect to a depth direction. Manufacturing method. And upsetting apparatus having upset punch upsetting pressurizes the round bar material axially in cooperation with knockouts in the die with substantially the same outer diameter and final outside diameter of the outer ring,
In cooperation with the knockout and the stripper in the die with a final outer diameter substantially the same inner diameter of the outer ring, the upsetting material, extruded in one axial direction, the final axial dimension substantially the same depth of the outer ring outer ring A molding device having an extrusion punch and a die, which simultaneously forms an inner ring equivalent portion corresponding to one inner ring combined with an outer ring on the bottom side of the cup molded product as a cup molded product having a corresponding portion;
A bottom punching device having a bottom punch and a die for punching the bottom of the portion corresponding to the inner ring of the cup-shaped product;
A punching punch for punching and separating the inner ring portion of the cup-shaped product with the bottom punched out, and a separation device for the inner ring corresponding portion having a die, and
In the die having the same inner diameter as the final outer diameter of the outer ring, in cooperation with a cylindrical pressure member that presses in the axial direction only from the upper end in the axial direction of the outer ring equivalent part separated from the inner ring equivalent part, Double row bearing outer ring with thick symmetrical part at the axial center by ironing the inner diameter from both ends in the axial direction without changing the outer diameter of the outer ring equivalent part while allowing flow extension at the lower end of the corresponding part A die that has upper and lower punches for forming the material, and causes the lubricant trapped between the outer ring equivalent portion and the die to flow out to the outside when pressurizing from the upper end in the axial direction by the upper punch or pressing member. And a squeezing forming device having a cylindrical stopper for finally positioning the lower end of the portion corresponding to the outer ring that is fluid-extended and provided with a lubricant drain hole provided in the double-row bearing. apparatus.   4. The apparatus for manufacturing a double row bearing according to claim 3, wherein the die having an inner diameter substantially the same as the final outer diameter of the outer ring is elastically supported. 5. The double row bearing according to claim 3 , wherein the pressurization of the pressurizing member with respect to the outer ring equivalent portion is set to be relatively strong only corresponding to the final stage of lowering of the pressurizing member. Manufacturing equipment. Simultaneously elastically supporting the die having an inner diameter substantially the same as the final outer diameter of the outer ring so as to reduce the friction between the outer ring equivalent portion and the die when the outer ring equivalent portion is pressurized in the axial direction. Lubricant that dies between the inner peripheral surface of the die and the outer peripheral surface of the thick wall portion corresponding to the outer ring 4. The apparatus for manufacturing a double row bearing according to claim 3, wherein the flow is caused to flow out through a lubricant hole.

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