JPH0211236A - Method for forming ring engaged with joint part - Google Patents

Abstract

PURPOSE:To absorb step difference at a joint part and to prevent abnormal wear from breaking out by forming a coil material with a guide roll and a core roll into the shape of a ring, forming a recessed and a projecting shape at the joints part of a cut-off ring, fitting them to the shape of a ring and punching the final shape by a press. CONSTITUTION:The coil material A is fed with a feed roll 6 by a length containing one roll and a working allowance at the joint part. While the coil material A is constrained by the guide roll 4 and the core roll 3 in the width direction of the material sheet, it is pressed against a bending roll to be formed into the ring. To secure inside stability of the ring and to remove the gradient of the residual stresses of its inner and outer diameters, tension is given by a pullback roller 1 to the radial direction to be formed. The product which has been formed in the shape of the ring is cut off by a cutter at a position 7, and rugged parts 8, 8a,... are formed by cutting, grinding, wire cutting, etc., at the end of the product. The male and the female part are joined with a suitable clearance between them and then pressed to be formed into a final shape or a backing plate. In this way, the step difference is absorbed and the abnormal wear of a frictional material is prevented.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a method for joining a ring-shaped joint portion formed by a ring forming machine, and relates to a method for joining a ring-shaped joint part formed by a wet multi-disc clutch for an automatic transmission. It is used when manufacturing backing plates, separate plates, and core plates.

(Conventional technique (Nete) Automatic transmission backing plate (B/P), separate plate (S/P) and core plate (C/P)
) uses a ring forming machine to form a coil material into a ring shape with a bending roll while being restrained in the direction of the material plate 1h by a guide roll and a core metal roll, and then cut the coil material into a straight line to a constant length. They were joined by arc welding or resistance welding, and then punched into the final shape by press working.

(Problem to be solved by the invention) However, the above molding method has the following problems.

(1) The hardness of the welded part and heat-affected zone of the ring-shaped joint increases rapidly (due to hardening), which causes functional problems, that is, abnormal wear of the friction material (lining). A normalizing process is required to prevent this.

(2) Damage to the friction material due to swelling of the weld;
To prevent this, a bevel process before welding or a trimmer process such as cutting and grinding after welding is required.

(3) The welded ring molded product is punched into the final shapes of B/P, S/P, and C/P using a press, but cracks occur in the welded parts during punching.

(4) It is likely to cause delayed fracture of the weld.

(5) Deformation occurs due to heat.

As described above, there is a problem in terms of quality stability, and the manufacturing cost increases because the number of steps is increased.

The technical object of the present invention is to provide a joining method that does not cause swelling of the welded part, cracking, deformation due to heat, etc. caused by welding the ring joint in ring manufacturing.

[Structure of the invention]

(Means for solving the problem) B/P used as a wet multi-disc clutch for automatic transmissions
In the method of manufacturing rings made of steel plates such as S/P and C/P using a ring forming machine, the coil material is bent by bending rolls while being restrained in the width direction of the material by guide rolls and core metal rolls. It is formed into a ring shape, cut to a length that takes into account the machining allowance for the seam, a concave shape and a convex shape are formed at the joint part of the cut ring, and the concave and convex shapes are fitted to form a ring shape. This is a ring forming method in which the ring is manufactured by punching it into the final shape using a press.

(Function) The coil material is formed into a ring shape by a ring forming machine with the joint part included, and the ends of the ring are provided with a convex shape and a concave shape, so the final molded shape with these concave and convex shapes fitted The ring is press-formed to form a ring, and there is no welding process to join the ring ends, so there will be no defects due to welding such as poor welding or uneven hardness at the ring-shaped ends. It is.

Furthermore, the uneven shape of the ring end allows it to shift in the thickness direction even if a force is applied in the ring thickness direction, so there is no distortion or misalignment of the ring end surface, and the ring can be placed on both sides of the ring. No significant wear phenomenon of the friction material occurs.

(Example) Examples will be described below.

FIG. 1 shows a method of manufacturing rings for B/P, S/P, and C/P using a ring molding machine.

A is a coil material, 1 is a pull-hack roll of a ring forming machine, 2 is a bending roll, 3 is a core roll, and 4 is a guide roll.

5 is the tip of the coil machine, 6 is a feed roll, and 7, indicated by a dotted line, is a straight cutting position.

W is [11] of the coil material, Dφ is the coil inner diameter, T is the coil plate thickness, and T2 is also the coil plate thickness.

In addition, the convex and concave shapes of the joints at the ends of the coils are 8.
Shown in a, 8b, 9a, 9b, 10a, 10b.

In the above structure, the joining method will be described as follows: When the ring forming machine is in operation, the coil material A is fed by the feed roll 6 by a length that takes into account one turn plus processing allowance for the seam.

The coil material A is pressed against the bending roll 2 and formed into a ring while being restrained in the width direction of the material by the guide roll 4 and the core metal roll 3.

The inner diameter Dφ of the ring is determined by the amount of vertical movement of the bending roll 2.

Further, in order to ensure the stability of the ring inner diameter and eliminate the residual stress gradient between the ring inner diameter and the ring outer diameter, the molding is performed while applying tension in the radial direction with the pullback roller 1.

Next, the ring-formed product is cut by a cutting machine at the position shown in 7 into lengths that take into account the machining allowance for each roll plus the seam.

The cut ring is processed by cutting, grinding, wire cutting, etc. to form uneven parts 8.8a...9.9a... as shown in Fig. 2.
is formed at the end, and after fitting the male part and the female part, the final shapes of B/P, S/P, and C/P are formed by pressing.

Fig. 3 shows an enlarged view of the concave and convex shapes of the ring end face shown in Fig. 2 (A). The dimensions are designed so that there is an appropriate gap between the shape and the convex shape, so even if there is a step in the thickness direction (caused by misalignment of the male and female parts during cutting), it can be removed by applying force. Since the level difference is easily eliminated, there is no abnormal friction where the friction material is scraped at the level difference.

〔Effect of the invention〕

The present invention has the following effects.

By creating an appropriate gap and joining the uneven parts without welding the joints of the rings, we can: (1) Eliminate the normalizing process; (2) Eliminate the beveling process or trimmer process. , (3) reduction of welding defects, and (4) improvement of productivity.

In addition, there are rings such as B/P and S/P in which the shape of the concavo-convex portion shown in Fig. 4 is fitted in a shape that cannot be compressed and moved (jigsy type). If this occurs, the friction material will be abnormally worn because it will not be able to absorb the difference in level, but in this example, even if compression is applied in the thickness direction, there is a clearance. It can absorb differences in level and does not cause abnormal wear on the friction material.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram of the ring manufacturing method in ring forming, Figure 2 (A) to (C) are explanatory diagrams of the clinch jig shape of the ring joint, and Figure 3 is an enlarged view of Figure 2 (A). figure,
FIG. 4 is a plan view of another conventional example. 2...Bending roll. 3... Core metal roll 4... Guide roll A... Coil material. W... Coil [11 8, 8a, 8b... Convex portion. 9.9a, 9b... recesses.

Claims (1)

[Claims] In a method for manufacturing rings, which are backing plates, separate plates, and core plates used as wet multi-disc clutches of automatic transmissions, using a ring forming machine, coil material is formed into guide rolls and core metal rolls. The material is formed into a ring shape using bending rolls while being restrained in the width direction, and cut to a length that takes into account the machining allowance for the joint, and concave and convex shapes are formed at the joint of the cut rings. A method of forming a ring in which the concave shape and the convex shape are fitted to form a ring shape, and the joint portion is manufactured by punching into the final shape using a press.