JPH057233Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a jig for heat treating a cup-shaped part having an escape hole at the bottom of the cup part.

(Prior Art) Conventionally, a heat treatment jig equipped with a basket for storing a product to be heat treated has been generally used (Japanese Utility Model Publication No. 20553/1983). however,
When heat treating cup-shaped parts, simply placing the parts in a basket tends to cause distortion and uneven heating, and a special jig is required.

FIG. 6 shows such a heat treatment jig, which consists of a tray 1 on which columns 2 are erected, and a lattice-shaped holder 4 attached to the columns 2 via collars 3. A support ring 5 for supporting the component W is integrally provided at each lattice point of the holder 4.
The component W is supported by each support ring 5 in a vertical state with its cup portion W1 facing upward, and is subjected to heat treatment as it is. The illustrated part W represents an input shaft that is a component of the transfer of a four-wheel drive vehicle, and has a shaft part W2 that is continuous with the cup part W1, and also has an oil drain at the bottom of the cup part W1. A hole W3 and a spline W4 are provided around the circumference of the cup portion W1.

With such a heat treatment jig, during quenching, the quenching fluid first flows from the shaft portion W2 of the part W to the circumferential portion of the cup portion W1, as shown by the arrow in the figure, and then enters the cup portion W1, and then enters the oil. Punch hole W3
The part W is finally cooled by the quenching liquid, and the specified quenching is completed.

(Problems to be Solved by the Invention) However, according to the conventional heat treatment jig described above, the time for the quenching liquid to circulate inside the cup portion W1 of the part W is inevitably slow, and as a result, the inside of the part W.
A difference occurs in the cooling rate on the outer surface, and as a result, distortion and uneven heating are likely to occur.Especially when the part W includes a product part such as the spline W4, deterioration in the accuracy of the spline W4 can be avoided. It had become like there wasn't. Furthermore, since the cup part W1 is supported upward, even if the oil drain hole W3 is present, the quenching fluid cannot be avoided, causing problems such as contamination of the later cleaning fluid. .

(Means for solving the problems) In order to solve the above-mentioned conventional problems, the present invention
A jig for heat treating a cup-shaped component having an escape hole at the bottom of the cup, which includes a tray and a plurality of support bars that stand upright on the tray and support the component from inside the cup, the support bars being vertically The gist is that the cross section has a modified cross section with a groove, and the intermediate portion in the longitudinal direction is configured as a bulge.

(Function) In the heat treatment jig having the above structure, since the support bar has an irregular cross section with vertical grooves, sufficient space is secured for the quenching liquid to circulate within the cup portion of the component supported by the support bar. The inner and outer surfaces of the component are uniformly cooled. Furthermore, since the bulging portion of the support bar restricts the parts from swinging more than necessary, adjacent parts will not collide with each other, and damage to the parts can be prevented. Furthermore, since the parts are supported with the cup facing downward, the quenching fluid can also be prevented from coming out.

(Example) Hereinafter, an example of the present invention will be described based on the accompanying drawings. In addition, in the following figure, the above-mentioned 6th
Elements that are the same as those shown in the figure are given the same reference numerals.
The explanation thereof will be omitted here. The target part of this example was the same input shaft as described above.

In FIGS. 1 and 2, reference numeral 11 denotes a lattice-shaped holder attached to a support 2 erected on the tray 1, and a support ring 1 is attached to each lattice point of the holder 11.
2 are provided integrally. Reference numeral 13 denotes a support bar, which is detachably attached to the support ring 12 by fitting its proximal shaft portion 14 into the support ring 12 and seating its flange portion 15 on the upper end of the support ring 12. It is being The support bar 13 has a sufficient thickness to allow the insertion of the component W into the cup portion W1, and a sufficient length to support the cup bottom of the component W and lift it from the holder 11. have.

The support bar 13 also has a longitudinal groove 16 on its periphery forming an irregular cross section (here, Y-shaped) (FIG. 2). Due to the presence of this vertical groove 16, the space within the cup portion W1 is substantially expanded when the component W is set, and the quenching fluid can easily enter the cup portion W1. Further, due to its Y-shaped cross section, the component W is allowed to swing in any direction, and always tries to maintain a vertical state. The support bar 13 further has a bulge 17 at its longitudinally intermediate portion, which prevents the component W from swinging more than necessary. Note that the support bar 13
The tip end is finished in an inverted triangular shape so as not to block the oil drain hole W3 of the component W.

With this configuration, as shown in Figure 1,
When the part W is set on the support bar 13 and quenched, the quenching fluid immediately flows into the cup part W1 of the part W as shown by the arrow, and then escapes to the outside through the oil drain hole W3. In this way, the part W
The inner and outer surfaces of the spline W4 are uniformly cooled, and the occurrence of distortion and uneven heating can be suppressed as much as possible, and the accuracy of the spline W4 can be guaranteed. Moreover, even if the tray 1 or holder 11 is deformed to some extent due to repeated heat treatment, the component W can always maintain a vertical posture as shown in FIG. Invasion will no longer be blocked. Furthermore, even if the parts W set on the support bar 13 try to swing greatly during conveyance of the tray 1, the swinging is restricted by the bulge 17, and adjacent parts collide with each other, damaging the spline W4. You can also avoid the risk of doing so.

Here, regarding the parts W (30 samples) that were actually heat treated using the above heat treatment jig,
The amount of change (μm) in the overball diameter of spline W4 was measured. For comparison, the amount of change in the overball diameter was similarly measured using the conventional heat treatment jig shown in FIG. As a result, according to this heat treatment jig, as shown in Fig. 4, the average () =
37 μm, standard deviation (σ) = 17 μm,
According to the conventional heat treatment jig, as shown in FIG. 5, the values were 99 μm and σ = 24 μm, making it clear that the present heat treatment jig is significantly superior in terms of quality assurance.

In the above embodiment, the input shaft of a transfer was targeted, but the object of the present invention is not limited to this, and the object can be any cup-shaped part having an escape hole. .

Further, in the above embodiment, the support bar 13 is attached to the holder 11, but in the present invention, the holder 11 can be omitted and the support bar can be attached directly to the tray 1.

(Effects of the invention) As explained above in detail, in the heat treatment jig according to the invention, the support bar has an irregular cross section with vertical grooves, so that the quenching liquid can be circulated inside the cup part of the part. is sufficient, the inner and outer surfaces of the component can be uniformly cooled, and there is an effect of suppressing the occurrence of distortion and uneven heating as well as deterioration of processing accuracy. In addition, the bulging portion of the support bar restricts the parts from swinging more than necessary, thereby preventing adjacent parts from colliding with each other, thereby preventing damage to the parts. Furthermore, since the part is supported with the cup portion facing downward, the quenching fluid can be prevented from being taken out, which has the effect of facilitating post-processing.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of the heat treatment jig according to the present invention;
Fig. 2 is a sectional view taken along the - line, Fig. 3 is a sectional view showing how the present heat treatment jig is used, and Fig. 4 is a frequency distribution diagram showing the quality of the heat-treated product obtained by the present heat treatment jig. FIG. 5 is a frequency distribution diagram showing the quality of heat-treated products obtained using a conventional heat treatment jig, and FIG. 6 is a cross-sectional view of the conventional heat treatment jig. DESCRIPTION OF SYMBOLS 1...Tray, 13...Support bar, 16...Vertical groove, 17...Bulging part, W...Part, W1...Cup part, W3...Oil drain hole (escape hole).

Claims (1)

[Scope of utility model registration request] A jig for heat treating a cup-shaped component having an escape hole at the bottom of the cup, which includes a tray and a plurality of support bars that stand up on the tray and support the component from inside the cup, the support bars being vertically 1. A heat treatment jig characterized in that it has an irregularly shaped cross section having a groove and a longitudinally intermediate portion thereof is a bulged portion.