JPH0123219B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a method for manufacturing a ring-shaped split outer ring used primarily in press bearings.

BACKGROUND ART Conventionally, in so-called press bearings, a configuration in which ring-shaped outer ring pieces 1 having shapes as shown in FIG. 1 are combined in a facing manner to form an outer ring 2 has been widely used. That is, as shown in FIG. 2, the outer ring 2 is formed by combining two ring-shaped outer ring pieces 1, 1 and holding them under pressure with the case 3, and the ball rolling grooves 2a of the outer ring 2 and the inner ring 4 A bearing is constructed by interposing balls 5 between ball rolling grooves 4a.

Until now, the ring-shaped outer ring piece 1 used in the bearing having the structure described above has been manufactured using pipe material. That is, after the pipe material is cut into appropriate dimensions, one side of its inner peripheral surface is turned to form the rolling surface 2' for the ball rolling groove. However, when pipe material is used, the cost of the material itself is high, making it difficult to reduce manufacturing costs. Therefore, the applicant has previously developed a method of manufacturing the ring-shaped outer ring piece 1 from a wire rod without using pipe material, and has published this method in Japanese Patent Application No. 52-86348 (Japanese Patent Application Laid-Open No. 54-20953). ) is published as. That is, Figures 3 and 4
As shown in the figure, a steel wire rod A with a circular cross section wound around a drum 6 is sent to a forming device 8 by a feeding device 7, where it is formed into a steel wire rod B with a square cross section. The wire rod B is cut into a predetermined size by the wire rod B by the size cutting device 10.

Next, the cut wire B is bent into a ring shape using the circular core bar 11 and the plurality of pressing heads 12a, 12b, and then the ring body 13 is rotated intermittently using the circular core bar 11 as a guide. table 14
The welding machine 16 welds the joint surfaces 17 at both ends of the ring body 13 while rotating the turntable 14 intermittently. After welding, the ring body 13 is subsequently sent to a turning process (not shown), where one side of its circumferential surface is turned,
It forms a ball rolling surface 2' for forming the ball rolling groove 2a.

The manufacturing method of the ring-shaped outer ring piece according to the above-mentioned Japanese Patent Application No. 52-86348 (Japanese Unexamined Patent Publication No. 54-20953) enables a significant reduction in manufacturing costs compared to the case of using conventional pipe materials. , which has high practical utility. However, the ring body 1 is curved by the circular core metal 11 and the pressing heads 12a, 12b...
3 and the turntable 1 using the core metal 11 as a guide.
4, and welding of the joining end surface 17 is performed with the ring body 13 removed from the core metal 11. Therefore, both ends of the ring body 13 do not come into contact accurately during welding, and
There is a problem in that the rate of occurrence of defective products due to the gaps and steps of these joining end surfaces 17 is extremely high.

In addition, when welding the joint end surfaces 17, distortion inevitably occurs in the ring body 13, making it difficult to manufacture a ring body 13 with accurate roundness, and resulting in a problem that only ring bodies 13 with low roundness can be obtained. be.

Furthermore, in order to form the ball rolling surface 2', the end of the inner circumferential surface of the ring body 13 is cut using a lathe, but as mentioned above, the roundness of the ring body 13 is low. There is a problem in that the work of forming the rolling surface 2' is extremely complicated, and the manufacturing cost of the ring-shaped outer ring piece 1 cannot be significantly reduced.

The present invention aims to solve the above-mentioned problems in the production of conventional outer rings for press bearings of this type, and aims to produce balls that have high roundness, excellent mechanical strength, and are smooth. The object of the present invention is to provide a method for manufacturing a ring-shaped split outer ring of a bearing, in which a ring-shaped outer ring piece having a rolling surface 2' can be manufactured continuously from a round steel wire with high efficiency.

In the present invention, a steel wire rod with a circular cross section is made into a steel wire rod with a square cross section using a forming device, and then the steel wire rod is fed into a ring manufacturing device in fixed size increments by a fixed size feeding device. The steel wire rod is placed above a circular core metal arranged horizontally, and the upper push head of the ring forming device and the movable blade of the cutting device are simultaneously operated downward to cut the steel wire rod. This is bent into a semicircular shape along the core metal, and then the side and lower push heads of the ring forming device are operated in a direction perpendicular to the axis of the core metal to form a ring body, and then the ring The ring body is moved onto the insulating core provided at the front end of the core by a pushing rod of a transfer device that operates in the axial direction of the core metal, and the ring body is moved by an upper push head of a welding device that operates simultaneously with the upper push head. While pressing and holding, both electrode butt heads were operated in a direction perpendicular to the axis of the core metal to bring them into contact with the ring body, and by passing electricity between the two electrode butt heads, the two ends of the ring body were welded together. After that, the ring body is transferred to a ball rolling surface forming device consisting of an upper mold, a lower mold, and a holding frame,
The basic structure is to press the upper mold to form a ball rolling surface at one end of the inner circumferential surface of the ring body using a press working method, and to correct the roundness of the ring body. It is.

Moreover, by adopting the above structure, it is possible to manufacture a ring-shaped outer ring piece having high roundness, excellent mechanical strength, and a smooth ball rolling surface with extremely high efficiency, and the manufacturing cost can be reduced. It is possible to significantly reduce the

Hereinafter, details will be explained based on an embodiment of the present invention shown in FIGS. 5 to 9. Note that the same reference numerals are used for parts common to FIGS. 1 to 4.

FIG. 5 is a manufacturing process diagram of an outer ring for a bearing according to the present invention, FIG. 6 is a schematic front view of the ring manufacturing machine, FIG. 7 is a schematic side view thereof, and FIG. 8 is an explanatory diagram of its operation.

Referring to FIG. 5, reference numeral 6 denotes a drum around which a steel wire rod A having a circular cross section is wound, from which the wire rod A is fed out to a forming device 8 by a feeding device 7. The forming device 8 is provided with two sets of rolls and a forming die, and the wire rod A having a circular cross section is formed into the wire rod B having a square cross section. Note that, of course, when using a circular rectangular wire rod of predetermined dimensions from the beginning, the forming device 8 may be omitted.

The wire rod B that has exited the forming device 8 is sent to a sizing sending device 9.
The wire material B is delivered to the ring manufacturing device C in predetermined sizes, and the ring forming device 18 of the ring manufacturing device C cuts the wire material B and forms it into a ring body at the same time. The ring body 13 formed by the ring forming device 18 is bonded at both ends by a welding device 19 integrated with the ring forming device 18.
7 is welded and then sent to the welding inspection device 20 for the joint surface 17.

The ring body 20 that has passed through the inspection device 20 is sent to the ball rolling surface forming device 21 by an automatic feeder, where it is press-formed to correct the roundness and form the ball rolling surface 2'. Formation takes place.

As shown in FIGS. 6 and 7, the ring manufacturing device C includes a ring forming device 18 and a welding device 19.
and a ring body 13 formed by the ring forming device 18.
a transfer device 22 for moving the material to the welding device 19;
, a cutting device 23 for the wire B, and a drive mechanism (not shown) for each of the devices. The ring forming device 18 includes an upper push head 18a, a lower push head 18b, two side push heads 18c, and a core bar 24, and the welding device 19 includes an upper push head 18a and a lower push head 18b. electrode push heads 19b and insulating core body 2
4a.

The wire B fed from the fixed size feeding device 9 to the left by a predetermined dimension along the upper surface of the cylindrical core metal 24 projected forward is transferred to the ring forming device 18.
A movable blade 2 that moves up and down integrally with the upper push head 18a.
3a and the fixed blade 23b (1 in FIG. 8), and then both ends are pushed downward along the core metal 24 by the upper push head 18a (2 in FIG. 8), and then the side portions are cut. After both ends of the push head 18c are bent along the core bar 24 (3 in Figure 8), the lower push head 18b is finally raised to shape the end joint (4 in Figure 8). , a complete ring body 13 is formed.

The formed ring body 13 is then transferred to a transfer device 22
is pushed out to the left by operating in the direction of the arrow in FIG. 7, and is moved onto the insulating core 24a of the welding device 19 fixed to the tip of the core metal 24 (5 in FIG. 8). Through the above operations, cutting of the wire B, forming it into a ring shape, and transferring it to the welding position are completed, and then the ring forming device 18 returns to the state 1 in FIG. 8 and starts cutting the ring B.

On the other hand, when the ring body 13 is transferred from the ring forming device 18 onto the insulating core 24a of the welding device 19, the upper push head 18 of the forming device 18 is moved from above.
The upper push head 19a of the welding device operates synchronously with a.
is lowered (6 in Fig. 8), and this is connected to the insulating core 24a.
Press it upward (7 in Figure 8). Thereafter, the electrode push heads 19b, 19b are moved to the side push heads 18 of the molding device 18.
It is pressed synchronously with c (8 in Figure 8), and both pressed heads 1
By applying current between 9b, both end joint surfaces 17 of the ring body 13 are resistance welded (8th
9) in the figure. Also, after welding is completed, transfer device 2
2, the ring body 13 is pushed forward by the next ring body 13 formed during welding of the previous ring body 13 (see 1 in Fig. 8).
0) is sent to the welding inspection device 20 by a conveyor (not shown). In addition, the ring forming apparatus 1
8, each push head of the welding device 19, and the extrusion rod 22a of the transfer device 22 are all cam mechanisms (not shown).
It is configured to operate at a constant timing through the
3 will be manufactured.

The ring body 13 whose integrity of the welded part has been confirmed by the welding inspection device 20 is then transferred to a ball rolling surface forming device 21 as shown in FIG. 9, where the roundness is corrected and the ball rolling surface 2 is ' is formed.

The ball rolling surface forming device 21 includes an upper die 21a.
It is configured as a press type, including a lower mold 21b and a holding frame 21c, and the lower mold 21b is supported via a spring 25. Welding inspection device 20
The ring body 13 transferred from the lower mold 21b
By pressing the upper die 21a, the upper die 21a, the lower die 21b, and the holding frame 21c are pressed, and the upper end of the inner circumferential surface is crushed into a substantially flat shape, thereby forming the ball rolling surface 2. ' is formed. or,
By pressing the upper mold 21a, the ring body 13
is shaped into an extremely accurate right circle along each mold 21a, 21b, 21c.

In the present invention, the ring body 13 formed as described above is
Since the ring body 13 is moved to the welding position using the core metal 24 as a guide without being removed from the core metal 24, there is no possibility that a large gap or step will be formed at the joints at both ends of the ring body 13. In addition, the ring body 13 is placed on the circular insulating core body 24a, and the upper push head 1
Since welding is carried out while being pressed by the electrode pushers 9a and the electrode push heads 19b, the welding of both end joints can be completed completely, and the ring body will not be distorted during welding.

Furthermore, since the molding of the ring body 13 and the welding of the previously molded ring body are performed simultaneously, the manufacturing efficiency of the ring body is greatly improved.

Furthermore, in the present invention, the ball rolling surface 2' of the ring body 13 is formed by pressing rather than turning, which greatly improves work efficiency and improves the roundness of the ring body 13 itself. This will also be corrected at the same time, which is extremely effective in improving the accuracy of this type of press bearing.

According to the present invention, compared to the conventional method for manufacturing this type of ring-shaped split outer ring, the production capacity is approximately three times (approximately 50 to 80 pieces per minute) and the manufacturing cost is also significantly reduced. Furthermore, the strength of the welded part, the smoothness and roundness of the ball rolling surface are significantly improved,
This has an excellent practical effect of increasing bearing precision after assembly.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a ring-shaped halved outer ring, and FIG. 2 is a sectional view of a press bearing using a ring-shaped halved outer ring. FIG. 3 is a schematic plan view of a conventional ring forming apparatus, and FIG. 4 is a schematic front view thereof. FIG. 5 is a manufacturing process diagram of the ring-shaped two-split outer ring according to the present invention;
The figure is a schematic front view of the main part of the ring manufacturing apparatus C, and FIG. 7 is a schematic side view of the main part. Fig. 8 is an explanation of the operation of the ring manufacturing apparatus C, and Figs.
Figure 0 shows the operation of the welding device. FIG. 9 is a sectional view of a main part of the ball rolling surface forming device, with the left half showing the state before operation and the right half showing the state after operation. A...Round steel wire rod, B...square steel wire rod, C...
... Ring manufacturing device, 1 ... Ring-shaped outer ring piece, 2'
. . . Ball rolling surface, 8 . . . Forming device, 9 . . . Sizing sending device, 17 . 18c... Side push head, 19... Welding device, 19a... Upper push head, 19b... Electrode push head,
20... Welding inspection device, 21... Ball rolling surface forming device, 22... Transfer device, 23... Cutting device,
24... Core metal.

Claims (1)

[Claims] 1. A steel wire rod A with a circular cross section is made into a steel wire rod B with a square cross section by a forming device 8, and then the steel wire rod B is fed into a ring manufacturing device C at fixed size intervals by a fixed size feeding device 9 to form the ring. The steel wire B is placed above the circular core metal 24 arranged in the horizontal direction of the manufacturing device C, and the upper push head 18 of the ring forming device 18 is
a and the movable blade 23a of the cutting device 23 are operated downward at the same time to cut the steel wire B and curve it into a semicircular shape along the core bar 24, and then to the side of the ring forming device 18. Part head 18b, 1
8b and the lower push head 18c in a direction perpendicular to the axial center of the core bar 24 to form a ring body 13, and then the extrusion rod 22a of the transfer device 22 operates the ring body 13 in the axial direction of the core bar 24. The ring body 13 is moved onto the insulating core body 24a provided at the front end of the core bar 24, and the ring body 13 is pressed and held against the core body 24a by the upper push head 19a of the welding device 19 that operates simultaneously with the upper push head 18a. Both electrode push heads 19b, 19b
is operated in a direction perpendicular to the axis of the core body 24a to bring it into contact with the ring body 13, and the two electrode push heads 19b, 19 are brought into contact with the ring body 13.
The both end joint surfaces 17 of the ring body 13 are welded by supplying current between b, and then the ring body 13 is transferred to the ball rolling surface forming device 21 consisting of an upper mold 21a, a lower mold 21b and a holding frame 21c, and the Upper mold 21a
A bearing ring in which a ball rolling surface 2' is formed at one end of the inner circumferential surface of a ring body 13 by pressing, and the roundness of the ring body 13 is corrected. A method of manufacturing a shaped two-split outer ring.