JP3147240B2 - Heat treatment jig - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat treatment jig, and more particularly to an improvement in a jig used for simultaneously heat-treating a plurality of annular heat-treated articles such as gears.

[0002]

2. Description of the Related Art Conventionally, when an annular heat-treated product such as a transmission gear is subjected to a heat treatment such as carburizing and quenching, as shown in FIGS.
And a heat treatment jig composed of a standing bar 9 erected on the tray 8 (Heat Treatment Vol. 30, No. 6, pp. 302-303). The tray 8 shown in FIG. 9 has a square plate shape, a circular engagement hole 81 at each vertex position of each square, and is supported by a column (not shown). As shown in FIG. 8, the standing bar 9 protrudes from the center of the Y-shaped base 90 to the back side from the center of the base 90 and engages with one engagement hole 81 of the tray 8. One engaged projection 91, and the opposite side of the engaged portion 91 from the base 90;
In other words, it has a loose fitting portion 92 which extends in a direction substantially perpendicular to the stitch and has a Y-shaped skeleton 93 connected in place in the horizontal direction.

A plurality of workpieces W to be heat-treated are loosely fitted to the loose fitting portions 92 by being stacked on the base portion 90 of the vertical rods 9, and a plurality of the vertical bars 9 to which the workpieces W are loosely fitted are engaged. Protrusion 91
Are engaged with the engaging holes 81 of the tray 8 mounted on the cart or the like, and are subjected to the heat treatment in a state where the setting is completed as shown in FIG.
Then, a quenching medium M such as a surrounding gas or quenching oil acts directly on the outer peripheral surface side of the article to be heat-treated W, as shown in FIG.
The tray 8 allows the quenching medium M to flow into the stitch from below, and the quenching medium M in the stitch passes through the gap between the base portion 90, the loose fitting portion 92, and the skeleton 93 to the inner peripheral surface side of the heat-treated article W. The heat treatment of the heat-treated article W is performed. In this case, since a plurality of heat-treated articles W are loosely fitted to the loosely-fitted portions 92 of the respective vertical rods 9, heat treatment of many heat-treated articles W can be performed at one time. It is advantageous in terms of aspect.

[0004]

However, in the above-mentioned conventional heat treatment jig, the engaged projection 91 of the standing rod 9 is a single columnar member that engages with the single engaging hole 81 of the tray 8. And the center axis O of the loose fitting portion 92 of the standing bar 9 is
Since the inner peripheral surface side of the heat-treated product W communicates with the stitches of the tray 8 only through a narrow gap, the quenching medium M flowing into the stitches of the tray 8 The quenching medium M hardly flows into the inner peripheral surface side of the heat-treated product W because a large amount flows out to the outer peripheral surface side of the heat-treated product W. This tendency becomes stronger as the ring-shaped heat-treated product has a smaller inner diameter. For this reason, the inner peripheral surface side of the heat-treated product W employing such a heat treatment jig tends to have a lower hardness and a lower case depth than the outer peripheral surface side. Further, even when the heat-treated product W is loosely fitted to the loose fitting portion 92 of the same vertical bar 9, the position at which the heat treatment medium W is loosely fitted because the amount of the quenched medium M flowing into the inner peripheral surface side is small. The degree of treatment varies depending on the type of treatment, and the quality of the heat treatment varies due to the difference in hardness and the depth of hardening depending on the position, and the inner diameter dimension also varies. Therefore, for heat-treated products that require high accuracy of the hardness of the inner peripheral surface, the depth of hardening, or the accuracy of the inner diameter, a partition jig called a spacer is placed between each heat-treated product in order to eliminate these problems. In this method, a horizontal bar supported by a tray is prepared, and each heat-treated product is laid across the horizontal bar. It takes a long time to set products, and the space between spacers between heat-treated products is wasted, reducing the number of loose fittings.
There is a problem that the number of jigs to be managed is increased and the cost is increased. In addition, in these methods, since it is difficult to insert a spacer or to support a horizontal bar, automation involves a difficulty.

The present invention has been made in view of the above-mentioned conventional problems, and is intended to be applied to heat-treated products having high required values of the hardness of the inner peripheral surface, the depth of the hardening, and the dimensional accuracy of the inner diameter. It is an object of the present invention to provide a heat treatment jig which can perform the setting in a short time and does not cause an increase in the number of jigs to be managed without a decrease in the number of loosely fitted articles to be heat treated.

[0006]

The heat treatment jig of the present invention comprises:
A stitch having a polygonal stitch shape, having an engaging portion at each apex position of the polygon, a tray for allowing a quenching medium to flow into the stitch, and a cover engaging with the engaging portion of the tray. The heat treatment jig, comprising: an upright bar having an engagement portion and a loose fitting portion that extends from the engaged portion in a direction substantially perpendicular to the stitch and into which a plurality of annular heat-treated products are loosely fitted. The bars must be at least 3 adjacent
The engaged portion is configured to engage simultaneously with the plurality of engaging portions, and a center axis of the loose fitting portion is located inside the stitches of the tray.

[0007]

In the heat treatment jig of the present invention, the engaged portion of the standing bar is configured to engage simultaneously with at least three adjacent engaging portions of the tray, and the center axis of the loose fitting portion is set at the center of the tray. Since it is located inside the stitch, the inner peripheral surface side of the heat-treated product communicates with the stitch of the tray via the loose fitting portion with a wide gap, and the quenching medium flowing into the stitch of the tray is It is easy to flow into the inner peripheral surface side. For this reason, the inner peripheral surface side of the article to be heat-treated using such a heat treatment jig is treated to the same hardness and hardening depth as the outer peripheral surface side. Further, since the amount of the quenching medium flowing into the inner peripheral surface side is large, the heat-treated product employing such a heat treatment jig can be loosely fitted regardless of the same or different vertical rods to be loosely fitted. It is processed uniformly regardless of the position where it is placed, and there is no variation in hardness, depth of sintering and inner diameter depending on the position.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments 1 to 3 embodying the present invention will be described below with reference to the drawings. (Embodiment 1) As shown in FIGS. 1 to 4, this heat treatment jig comprises a stitch-shaped tray 1 and a standing bar 2 erected on the tray 1.

The tray 1 is the same as the conventional one, as shown in FIG. That is, the tray 1 has a square plate shape, a circular engaging hole 11 at each vertex position of each square, and is supported by a column (not shown). As shown in FIGS. 1 (a) and 1 (b), the standing bar 2 projects in a fan-like manner from the top of each of the cross-shaped pedestals 20 to the back of each of the tops of the pedestals 20 at the apex positions of the squares. 4 that engages with the four engagement holes 11
The engaged projections 21 and the respective engaged projections 21
And a loose fitting portion 22 in which a cross-shaped skeleton 23 is connected in place in the horizontal direction while extending in a direction substantially perpendicular to the stitch.

A plurality of the heat-treated articles W are loosely fitted to the loose fitting portions 22 by being stacked on the pedestal portion 20 of the uprights 2, and four of the plurality of uprights 2 into which the heat-treated articles W are loosely fitted. The engaged projections 21 are engaged with four adjacent engaging holes 11 of the tray 1 mounted on a cart or the like, and are subjected to heat treatment in a state where the setting is completed as shown in FIG. Then, a quenching medium M such as a surrounding gas or quenching oil acts directly on the outer peripheral surface side of the standing bar 2, and as shown in FIG. 4, the quenching medium M flows into the stitches from below the tray 1. Then, the quenching medium M in the stitch acts on the inner peripheral surface side of the standing bar 2, and heat treatment of the heat-treated article W is performed.

At this time, in this heat treatment jig, the engaged projections 21 of the standing bar 2 are simultaneously engaged with the four adjacent engagement holes 11 in the tray 1, and the center axis O of the loose fitting portion 22 is formed. Are located inside the stitches of the tray 1. For this reason, the inner peripheral surface side of the article to be heat-treated W is the base portion 20, the loose fitting portion 22, and the skeleton 2.
3, the quenching medium M flowing into the stitches of the tray 1 easily flows into the inner peripheral surface side of the article W to be heat-treated. Therefore, the inner peripheral surface side of the article to be heat treated W employing this heat treatment jig is processed to the same hardness and hardening depth as the outer peripheral surface side.
Further, since the amount of the quenching medium M flowing into the inner peripheral surface side is large, the heat-treated article W employing such a heat-treating jig can be used regardless of whether the vertical bar 2 to be loosely fitted is the same or not, and It is processed uniformly regardless of the position where it is loosely fitted, and there is no variation in hardness, depth of tanning, and inner diameter depending on the position. (Embodiment 2) As shown in FIGS. 5 and 6, this heat treatment jig comprises a stitch-shaped tray 3 and a standing bar 4 erected on the tray 3.

As shown in FIG. 6, the tray 3 has a rhombic plate shape with stitches, has a circular engaging hole 31 at each vertex position of each rhombus, and is supported by a column (not shown). is there. The standing bar 4 is, as shown in FIGS.
A Y-shaped pedestal 40 and three engaged members that protrude from the respective ends of the pedestal 40 at the apexes of the equilateral triangle to the back side in a fan shape and engage with three adjacent engagement holes 31 in the tray 3. It has a mating projection 41 and a free-fit portion 42 which is opposite to each engaged projection 41 from the base portion 40, that is, a Y-shaped skeleton 43 extending in a direction substantially perpendicular to the stitch and connected in place in the horizontal direction. Things.

In this heat treatment jig, the three engaged projections 41 of the standing bar 4 are engaged with the three adjacent engagement holes 31 of the tray 3, and the heat treatment is performed in a state where the setting is completed as shown in FIG. Provided. When this heat treatment jig is employed, the same operation and effect as those of the first embodiment can be obtained. (Embodiment 3) This heat treatment jig employs the standing bar 5 shown in FIGS. 7 (a) and 7 (b). Since the tray is the same as that of the first embodiment, the same reference numeral is assigned to the first embodiment, and the detailed description is omitted.

The standing bar 5 has a substantially square base 50 having a circular hole in the center, and four fan-like projections protruding rearward from the respective top ends of the base 50 at the apex positions of the squares, respectively, in the tray 1. Four engagement projections 5 that engage with engagement holes 11
1, a skeleton 5 extending in a direction opposite to each engaged projection 51 from the base 50, that is, in a direction substantially perpendicular to the stitch, and having a cross shape in the horizontal direction.
3 is a loose fitting portion 52 connected in place, and a cylindrical guide portion 53 projecting from the base portion 50 to the same side as each of the engaged projections 51.
And has

In this heat treatment jig, the quenching medium M in the stitches of the tray 1 is further introduced into the inner peripheral surface side of the article to be heat treated W by the guide portion 53 of the vertical rod 5, and the inner peripheral surface of the article to be heat treated W The side can be more suitably heat treated. Other functions and effects can be achieved in the same manner as in the first embodiment. In the heat treatment jigs of Examples 1 to 3, the vertical bars 2, 4,
Since the number of the engaged projections 21, 41, 51 of 5 is three or four, it is possible to stand only with the standing rods 2, 4, 5.
The handling and stocking before and after the heat treatment can be easily performed.

The standing rods 2, 4, and 5 in the heat treatment jigs of the first to third embodiments have three or four engaged projections 2.
The central axis O is positioned by 1, 41, and 51.
For this reason, positioning is easily performed, and even if automation is intended, the positioning mechanism can be omitted. In addition, the tops of the standing rods 2, 4, and 5 are shown in FIG.
As shown in the vertical bar 9 shown in FIG.
There is no need to provide the support 4, and there is no need to provide a steady rest jig (not shown) for supporting the receiving portion 94. Therefore, a larger number of heat-treated products W can be loosely fitted to one of the standing rods 2, 4, and 5 than before, and the workability can be improved.

Further, when the standing bar 9 in the conventional heat treatment jig shown in FIG.
, And a bending stress is always applied to the engaged projection 91 due to a minute gap between the engaged projection 91 and the engaging hole 81. Although the service life was short, three or four engaged protrusions 2 were used for the standing rods 2, 4, and 5 in the heat treatment jigs of Examples 1 to 3.
The load is dispersed by 1, 41, 51, and three or four engaged projections 21, 41, 51 form a minute gap between the engaged projections 21, 41, 51 and the engaging holes 11, 31. Absorbing, no bending stress acts on the engaged projections 21, 41, 51, and the life is extended.

In the first to third embodiments, the trays 1, 3
The engaging holes 11 and 31 are adopted as the engaging portions of
The engaged projections 21, 41, and 51 were employed as the engaged parts of the trays 4 and 5, but the engaging projections were employed as the engaging parts of the tray 1 and the engaged holes of the standing rod 2 were employed as the engaged parts. Can also be adopted.

[0019]

As described in detail above, in the heat treatment jig of the present invention, the engaged portion of the standing bar is configured to engage simultaneously with at least three adjacent engaging portions of the tray, The center axis of the loose fitting portion is located inside the stitch of the tray. For this reason, if this heat treatment jig is adopted, the inner peripheral surface side of the heat-treated product can be treated to the same hardness and the hardening depth as the outer peripheral surface side without employing the conventional method. it can. In addition, heat-treated products using this heat treatment jig
Without adopting the conventional method, regardless of the same or non-identical of the vertical bar to be loosely fitted, regardless of the position where it is loosely fitted, it is uniformly processed, the hardness according to the position, the hardening depth There is no variation in inner diameter dimensions.

Therefore, if this heat treatment jig is employed, it is not necessary to employ the conventional method, so that the heat treatment product can be set in a short time, and the number of loose fits of the heat treatment product can be reduced. And no increase in jigs to be managed. Therefore, by employing this heat treatment jig, heat treatment can be performed at a low cost even on a heat-treated product having high required values of the hardness of the inner peripheral surface, the depth of the hardening, and the dimensional accuracy of the inner diameter.

[Brief description of the drawings]

FIG. 1 relates to a vertical bar in a heat treatment jig of Example 1,
(A) is a side view, (b) is a plan view.

FIG. 2 is a plan view of a tray in the heat treatment jig of the first embodiment.

FIG. 3 is a plan view showing a state in which a standing bar is erected on a tray in the heat treatment jig of the first embodiment.

FIG. 4 is a cross-sectional view taken along line AA of FIG. 3, showing a state in which a standing bar is erected on a tray in the heat treatment jig of Example 1.

FIG. 5 relates to a vertical bar in the heat treatment jig of Example 2.
(A) is a side view, (b) is a plan view.

FIG. 6 is a plan view showing a state in which a standing bar is erected on a tray in the heat treatment jig of the second embodiment.

FIG. 7 relates to a vertical bar in the heat treatment jig of the third embodiment.
(A) is a side view, (b) is a plan view.

FIG. 8 is a side view of a standing bar in a conventional heat treatment jig.

FIG. 9 is a plan view showing a state in which a standing bar is erected on a tray in a conventional heat treatment jig.

FIG. 10 is a sectional view taken along the line BB of FIG. 9, showing a state in which a standing bar is erected on a tray in a conventional heat treatment jig.

[Explanation of symbols]

1, 3, tray 11, 31, engaging hole (engaging portion) 2, 4, 5, standing bar 21, 41, 51 engaged projection (engaged portion) 22, 42, 52 free fitting portion O: Central axis M: Hardened medium W: Heat-treated product

Claims (1)

(57) [Claims] A stitch having a polygonal stitch shape, an engagement portion at each vertex position of the polygon, a tray for allowing a quenching medium to flow into the stitch, and an engagement portion of the tray. And a vertical bar having a loosely-fitted portion extending from the engaged portion in a direction substantially perpendicular to the stitch and into which a plurality of annular heat-treated products are loosely fitted. The vertical bar has the engaged portion configured to engage simultaneously with at least three adjacent engaging portions, and a center axis of the loose fitting portion is positioned inside the stitch of the tray. Heat treatment jig characterized by performing.