JPS60174286A - Welding method of hollow shaft - Google Patents

Abstract

PURPOSE:To weld easily a hollow shaft with high joint strength by press-fitting a ring body into the press-fitting recesses formed to the respective inside peripheral parts at the split ends of both split shaft bodies, butting both split shaft bodies and welding the butt part. CONSTITUTION:Press-fitting recesses 14, 17 are formed in the inside peripheral parts at ends of respective large diameter shaft parts 13 of split shaft bodies 10, 11 consisting of small diameter shaft parts 12 continuous with hollow large diameter shaft parts 13. One end of a ring body 15 having the outside peripheral parts at both ends each formed to a circular coincal face 16 is press-fitted into the recess 14 of one body 10 and further the other end of the body 15 is press- fitted into the recess 17 of the other body 11. The split end faces 10a, 11a in the parts 13 of both bodies 10, 11 are thus butted to each other. The butt part 18 is subjected to electron beam welding, by which the hollow shaft having high joint strength is obtd. with simple positioning and preparatory plan without generating spatters.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method of welding a hollow shaft such as a lower roller shaft or an idler shaft that is forged into two parts.

Conventional technology When electron beam welding a hollow shaft, it is necessary to (1) ensure that the joint strength satisfies the design strength, (2) that the inside of the shaft is not contaminated by spatter during welding, and (3) before welding. The aim is to design a welded joint structure that is easy to set up.

However, conventional general hollow shaft welding methods have not been able to provide a welded joint structure that satisfies the matters listed in (1), (2), and (3) above.

That is, generally, the hollow shaft 1 is manufactured by abutting the divided shaft bodies 2, 30 divided end faces 2a and 3a, and electron beam welding the abutting portions, as shown in FIG.

When welding the abutting portions, as shown in FIG. and both end faces 2a.

3a were abutted, the annular protrusion 4 was inserted into the annular recess 5, and the abutment N5 of the two split ends 2a, 3a was welded. However, in this case, stress concentration occurred in the P portion under a predetermined bending load, resulting in a decrease in strength.

In addition, in the past, as shown in Fig. 3, there was a structure in which the divided end surfaces 2a and 3a of the divided shaft body 2.30 were brought into contact with each other, and the abutting portions were welded, but in this case, the hollow shaft 1 Spatter 7 was scattered in the internal oil pool 6, and setup and manual operations (handling) for positioning when the two side end surfaces 2a and 3a abutted against each other were difficult.

Furthermore, in the past, as shown in FIG.
There is a device in which the divided end surfaces 2a and 3a are brought into contact with each other, and the member 8 is placed on the lower side of the abutted portion, and this abutted portion is welded. This made setup and manual operations for positioning difficult.

OBJECTS OF THE INVENTION It is an object of the present invention to alleviate stress concentration in a welded part (joint part), to prevent the generation of spatter due to the electron beam passing through to the oil pool side, and to reduce the stress concentration in the welded part (joint part). It is an object of the present invention to provide a hollow shaft welding method that facilitates setup and manual operation for position alignment when the I+ split end faces 10a and lla meet.

Structure of the Invention The present invention forms a press-fit recess 14 at the inner circumference of the divided end of one divided shaft 100, and a press-fit recess 17 at the inner circumference of the divided end of the other divided shaft 110. After press-fitting one side of the ring body 15 into the press-fitting recess 14 of the split shaft 10, the other side of the ring body 15 is press-fitted into the press-fitting recess I7 of the other split shaft 10, thereby forming the both-side shaft 10. +1 split end face 10
a and lla, and these divided end faces 10a.

The abutting portions of 11a are welded.

Embodiment An embodiment of the present invention will be described with reference to FIGS. 5 and 6.

10 and 1.1 in the drawing are divided +11b bodies, and these divided shaft bodies IQ and II have a large diameter shaft part 1 on a small diameter shaft f% + 2.
3 in a row, and the large diameter l1ll+ portion 13 is hollow. Press-fit recesses 14 and 17 are formed in the inner peripheral portions of the large diameter shaft portions 13 of these split shaft bodies 10 and 11.

Reference numeral 15 denotes a ring body, and the ring body 150 has both ends and an outer periphery formed between cones 16.

Then, one side of the ring body 15 is press-fitted into the press-fit recess 14 of one split shaft body 10, and the other side of the ring body 15 is press-fitted into the press-fit recess 17 of the other split shaft body 11, so that both halves of the split shaft body 10 are press-fitted. Shaft body 1
0. The end face of the large diameter shaft portion 13 of II, that is, the division 9i6t
'IIJJ loa, , collate l la.

Next, the welded portion 18 formed by these divided end faces lQa and lla is electron beam welded to form the hollow shaft 1 shown in FIG.
Make 0.

Effects of the Invention According to the method of the present invention, since the shaft bodies 10 and 11 on both sides are joined by press-fitting the ring body 15 into the press-fitting recess 14.17, the stress concentration in the welded part 18 can be alleviated, and the oil Damari 1
This not only prevents the electron beam from passing through to the side 9 and spatter, but also prevents the split end blood 10a,
The setup and manual operations for this alignment become easier when aligning the lla.

[Brief explanation of the drawing]

Figure 1 is a front view of the hollow shaft, Figure 2 A, Figure 3, Figure 3 C, 2, and Figure 4 E are explanatory diagrams of the welding process of the hollow shaft by conventional welding methods, and Figure 5 is an explanatory diagram of the welding process of the hollow shaft by the conventional welding method. A front view of a hollow shaft manufactured by the welding method according to the present invention, FIG.
FIG. 6 is an explanatory diagram of a process of welding a hollow shaft by the welding method according to the present invention. to, 1.1 is the split shaft body, 14.17 is the press-fit recess, 15
is a ring body. Applicant Komatsu Ltd. Representative Patent Attorney Masaaki Yonehara Patent Attorney Tadashi Hamamoto

Claims (1)

[Claims] A press-fit recess 14 is formed in the inner circumference of the divided end of one divided shaft body 100.
At the same time, a press-fit recess 17 is formed in the inner circumference of the split end of the other split shaft 110, and one side of the groove body I5 is press-fitted into the press-fit recess I4 of one split shaft 10. The other side portion of the ring body 15 is press-fitted into the press-fit recess 17 of the other split shaft body 10 to separate the split ends 11ii10a of both side shaft bodies to, II.
. A hollow shaft welding method characterized in that the split end faces 10a and the abutting portions of the lla are welded.