JP2000087118A - Composite parts of sintered member and refined member and production thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide lightweight and inexpensive composite parts of a sintered member and a refined member free from the partial shortage of rigidity. SOLUTION: A sintered member in primary parts is joined to a refined member of secondary parts by brazing, the refined member in the secondary parts is joined to a refined member of third parts and for example, a planetary carrier in which the sintered member in the primary parts is composed of a carrier bridge 8, the refined member in the secondary parts is composed of a carrier plate 9 and the refined member in the third parts is composed of a helical internal gear 10, is useful.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite part of a sintered member and a smelted member, and the construction of a planetary carrier and a rotating part such as a gear and a cam used in an automatic transmission of an automobile and a method of manufacturing the same. About.

[0002]

2. Description of the Related Art Planetary carriers used in automatic transmissions of passenger cars and the like are conventionally manufactured by melting and casting (at least melting and casting processes, and include steel, mild steel, tool steel, and alloy steel). , Including cast iron). However, since the number of man-hours required for machining is increased and the cost is increased, the use of a sintered member that requires less machining and has a high yield is being studied.

[0003] When a carrier bridge of a planetary carrier is manufactured by using a steel plate which is an ingot formed by press molding, the steel plate has a constant thickness (t: shown in FIG. 1). In addition, the periphery of the column portion of the carrier bridge has the same thickness.

When a high load is applied to the column of the carrier bridge, the thickness of the column (T: shown in FIG. 1) must be increased. However, when a carrier bridge of a planetary carrier is manufactured using a press-formed steel plate, t = T.

However, in the method using a sintered member, t << T can be set according to the load, which is the reason why a method using a sintered member having a high degree of freedom in shape design is being studied. .

The above-mentioned matter is not limited to the planetary carrier, but also for general mechanical parts, due to the design concept of cost reduction by using the right material in the right place, long ones such as shafts have complicated shapes such as melted members, shafts and cams. The use of a sintered member has been studied.

Conventionally, for example, there is a planetary carrier as shown in FIG. That is, a sintered member 18 composed of a plate 28 having the shaft hole 12 and the side plate 15 and a sintered member 19 composed of the plate 14 having the inner spline 13 are manufactured.

Two separately manufactured sintered members 18, 19
Are stacked, a brazing material is inserted into a through hole 17 provided at a position corresponding to the end face 16 of the side plate 15, the brazing material is heated, and the two sintered members 18 and 19 are brazed and joined. is there.

As a related technique of brazing, Japanese Patent Publication No. 58-34524 or Japanese Patent Publication No. 57-44433 filed by the present applicant discloses that at least one compact is formed with a concave portion. It discloses a technique in which a brazing material compacted into a recess is inserted and sintered so that the brazing material permeates and joins the joining surfaces of the two sintered members.

Furthermore, Japanese Patent Publication No. 6-37644 discloses a method of manufacturing a planetary carrier by simultaneously sintering a green compact for a sintered member and brazing the two sintered members. ing.

According to the method, in order to obtain a structure in which a space (for example, a space for mounting a pinion gear) is formed by each of the two sintered members, two separate members are avoided from being integrally molded from the sintering powder. Are compacted, sintered and sintered.

[0012]

When the planetary carrier as described above is divided into two parts, separate green compacts are formed, and the two are sintered and brazed, the internal gear of the planetary carrier is also required. Since the sintered member is the same as the carrier bridge, there is a demand that the internal gear be made of steel which is a smelting member. However, it has been difficult to manufacture a planetary carrier whose internal gear portion is made of steel by a conventional sintering method.

Further, when the planetary carrier as described above is divided into two parts, separate green compacts are formed, and the two are sintered and brazed, the distortion caused by the heat effect of the brazed joint is reduced. Due to the occurrence, there is a problem that the dimensions of the planetary carrier are likely to be out of order.

Further, in a process of manufacturing a general mechanical part such as a planetary carrier by machining a conventional ingot material, there is a welding process, and a welding device such as an electron beam device is installed. It is economical because the installed welding device can be used effectively.

In the present invention, instead of molding two separate green compacts and sintering and brazing the two, a single green compact is used to solve the problem. is there.

[0016]

SUMMARY OF THE INVENTION A sintered member of a first part is brazed to a smelted member of a second part, and a smelted member of the second part is joined to a smelted member of a third part. A composite component of a sintered member and a smelted member is useful.

The sintered member of the first part is a carrier bridge,
It is useful to use a planetary carrier in which the smelting member of the second part is a carrier plate and the smelting member of the third part is a helical internal gear.

The sintered compact of the first part and the smelting member of the second part are fitted to each other, and the brazing material is inserted into a through-hole provided in the second part in contact with the joint surface between the first and second parts. And, at the same time as sintering the green compact for a sintered member, brazing is performed on the bonding surface with the second component.

Next, the second part is joined to the smelted member as the third part to produce a composite part of the sintered member and the smelted member. The joint between the second component and the third component is formed by any one of electron beam welding, arc welding, MIG welding, and argon welding.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Conventionally, sintered parts have been produced by brazing and joining sintered members 1, 2, and 3 as shown in FIG. In order to avoid molding the sintered member integrally, the sintered member is divided into two sintered compacts 1 and 2 by two compacts, and a space 2 is formed.
0 (the part where the pinion gear etc. are mounted).

If there is a difference in the expansion and contraction of the two brazed sintered members 1 and 2, whether or not the sintering and brazing of the two members are performed at the same time or at the same time, they are integrated. Distortion occurs in the sintered part as compared with the molded and sintered one. In addition, when the space 20 as shown in FIG. 4 is provided, and when the sintered member 3 is made of the smelted member 4, the joining of the two is generally not easy.

Therefore, as shown in FIG. 3, by sintering the compact formed by multi-stage molding or the like, the space 20
The sintering member 5 and the smelting member 6 having the above are brazed and joined.

In this case, if the sintering of the green compact and the brazing are performed at the same time, the distortion of both of them is removed at the same time, and the members 5 and 6 having no distortion can be obtained. Further, since both of the smelting members 6 and 7 are smelting materials, strong joining without distortion is possible by welding.

As shown schematically in FIG. 2, the sintered member 22 has a complex shape such as a gear (not shown), and a cylindrical member or a cylindrical member, which is a smelted member, has a core portion. At the same time as the sintering of the green compact for the sintering member 22, the sintering member and the smelting member are brazed and joined, and the cylindrical member or the cylindrical member, which is the smelting member, is smelted to the
It is also possible to manufacture mechanical parts (rotary parts and the like) joined to the same.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in more detail with reference to the illustrated embodiments. FIG. 1 ((a) cross-sectional view, (b)
Is a view from below. ), This embodiment shows a planetary carrier which is a composite part, which has a boss 25 having a shaft hole in the center, and a plurality of pillars 26 on a peripheral portion opposite to the boss 25. A carrier bridge 8 formed by sintering having a space 20 for mounting a pinion gear, a carrier plate 9 obtained by press-finishing a steel plate-like member, and a gear (gear) 23 by machining the inner surface of a steel cylindrical member. The helical internal gear 10 is machined and finished.

A method for producing the product of the present invention will be described. A green compact to be the carrier bridge 8 was produced by multi-stage molding so that the iron powder for sintering containing Cu and C had a density of 6.8 mg / m ³ .

Further, a steel plate member is press-finished to manufacture a carrier plate 9 having five through holes 11 provided on the outer periphery as shown in FIG. 1B. The carrier plate 9 is fitted with a projection (not shown) provided on the column 26 of the green compact to be the carrier bridge 8.

A through hole 11 of the carrier plate 9 which is a brazing hole is filled with a Ni-Cu-Mn-Fe-Si-B-based brazing material. 9 for 1 hour at a temperature of 1130 ° C.
Sintering and brazing were performed simultaneously under the conditions of 5 minutes.

Then, by ordinary electron beam welding, FIG.
As shown in (a), an outer peripheral surface 21 on which a carrier plate 9 is fitted is joined to a helical internal gear 10 which is a steel member whose inner surface is lathe-finished into a gear (gear) 23.

Sufficient joining strength was obtained by ordinary MIG welding instead of the electron beam welding because the two to be joined are made of steel. Further, this planetary carrier was integrated without distortion.

[0031]

According to the composite part of the sintered member and the smelted member according to the present invention, the portion formed by the sintered member is lighter than the one formed by steel, and the thickness can be designed according to the load. There is no partial lack of rigidity, and it can be provided at low cost.

For example, a planetary carrier, which is a composite part in which a space in which a pinion gear or the like is to be mounted is made of an integrated sintered member, is used for an automatic transmission that also meets recent demands for increasing the engine torque of an automobile. it can.

[Brief description of the drawings]

FIG. 1 is a view showing a planetary carrier which is a composite part of a sintered member and a smelted member according to the present invention, wherein (a) is a cross-sectional view and (b) is a view from below.

FIG. 2 is another view of a composite component of a sintered member and a smelted member.

FIG. 3 is another view of a composite part of a sintered member and a smelted member according to the present invention.

FIG. 4 is a conventional view of a part in which a space 20 is formed by two sintered members 1 and 2;

FIG. 5 is a conventional view of a planetary carrier.

[Explanation of symbols]

 1, 2, 3, 5, 18, 19, 22: Sintered member 4, 6, 7, 27: Smelted member 8: Carrier bridge 9: Carrier plate 10: Helical internal gear 11, 17: Through hole 12: Shaft hole 13: Internal spline 14, 28: Plate 15: Side plate 16: End surface 20: Space 21: Outer peripheral surface 23: Gear 24: Core portion 25: Boss 26: Column portion

Claims (4)

[Claims] 1. A sintering member of a first part is brazed to a smelting member of a second part, and the smelting member of the second part is a third member.
A composite part comprising a sintered member and a smelted member, which is joined to the smelted member of the part. 2. A sintering member of the first component is a carrier bridge, a smelting member of the second component is a carrier plate, and a smelting member of the third component is a planetary carrier including a helical internal gear. A composite part comprising the sintered member according to claim 1 and a smelted member. 3. A through-hole formed in the second part, which fits the sintered compact of the first part and the smelted member of the second part, and is in contact with the joining surface of the first part and the second part. And, at the same time as the sintering of the green compact for a sintered member, brazing is performed on the joining surface with the second component.
A method for producing a composite part of a sintered member and a smelted member, wherein the composite member is joined to a smelted member as a part. 4. The bonding of the second part and the third part,
The method for producing a composite part of a sintered member and a smelted member according to claim 3, wherein the composite part is formed by any one of electron beam welding, arc welding, MIG welding, and argon welding.