JPH0598342A - Jig for heat treatment - Google Patents

Abstract

PURPOSE:To obtain a good quality heat treatment product with a small number of jigs in a short time for setting by forming engaging parts of a standing rod to three or more in the jig for executing the heat treatment to plural annular products of gears, etc., at the same time and positioning the axis of a loose setting part. CONSTITUTION:A tray 1 has square plate-shape in the network and round engaging hole 11 at each apex position in each square. The standing rod 2 has four engaging projections 21 protruding to the back side at each apex position in each square from each tip part in a crossing shaped base part 20 and the loose setting part 22 extended in the almost right angle direction to the network from the base part 20 in the reverse side of the projections 21 and connected with a crossing shaped skeleton 23 in the horizontal direction. The plural products W to execute the heat treatment are piled on the base part 20 and set to the loose setting part 22 and axis O of the loose setting part 22 is positioned in the inner part of the network and the four projections 21 are engaged with the adjoining four engaging holes 11 in the tray. Quenching medium is passed into the network and by acting this medium in the inner peripheral surface side of the standing rod 2, the heat treatment is applied to the products W to execute the heat treatment. By this method, the inner peripheral surface side of the product to execute the heat treatment can be treated so as to have the same hardness and surface hardened depth as the outer peripheral surface.

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 improvement of 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 gear for a transmission is subjected to heat treatment such as carburizing and quenching, as shown in FIGS.
It is practiced to use a heat treatment jig composed of the above and a standing rod 9 which is erected on the tray 8 (heat treatment No. 30, No. 6, pages 302 to 303). The tray 8 shown in FIG. 9 has a plate shape with square stitches, has a circular engaging hole 81 at each vertex position of each square, and is supported by a column (not shown). Further, as shown in FIG. 8, the upright bar 9 engages with a Y-shaped base portion 90 and one engagement hole 81 of the tray 8 which protrudes in a columnar shape from the center of the base portion 90 to the back side. One engaged projection 91 and the opposite side of the base 90 from the engaged projection 91,
That is, it has a loose fitting portion 92 in which a Y-shaped skeleton 93 in the horizontal direction is connected in place while extending in a direction substantially perpendicular to the stitch.

The heat-treated products W are stacked on the base portion 90 of the vertical rod 9 so that a plurality of them are loosely fitted in the loose fitting portions 92, and the plurality of vertical rods 9 on which the heat-treated products W are loosely engaged are engaged. Protrusion 91
Is engaged with the engaging hole 81 of the tray 8 mounted on the dolly or the like, and is subjected to the heat treatment in the set-completed state shown in FIG.
Then, the quenching medium M such as the surrounding gas or quenching oil directly acts on the outer peripheral surface side of the article to be heat treated W, and as shown in FIG.
The tray 8 allows the quenching medium M to flow into the stitches from below, and the quenching medium M in the stitches 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 article W to be heat treated. The heat treatment of the article to be heat treated W is performed. In this case, since a plurality of products W to be heat-treated are loosely fitted in the loose fitting portions 92 of each of the upright bars 9, a large number of products W to be heat-treated can be heat-treated at one time. It is advantageous in terms.

[0004]

However, in the above-mentioned conventional heat treatment jig, the engaged projection 91 of the upright bar 9 is of a single cylindrical shape that engages with the single engagement hole 81 of the tray 8. And the central axis O of the loose fitting portion 92 of the upright bar 9 is the tray 8
Since the inner peripheral surface side of the article to be heat treated W communicates with the stitches of the tray 8 only with a narrow gap, the quenching medium M flowing into the stitches of the tray 8 is A large amount flows out to the outer peripheral surface side of the article to be heat treated W, and the quenching medium M does not easily flow into the inner peripheral surface side of the article to be heat treated W. This tendency becomes stronger in an annular heat-treated product having a smaller inner diameter. Therefore, the inner peripheral surface side of the product W to be heat-treated employing such a heat treatment jig is likely to have a lower hardness and a lower case hardening depth than the outer peripheral surface side. Further, even if the heat-treated product W is loosely fitted to the loose fitting portion 92 of the same upright bar 9, since the amount of inflow of the quenching medium M to the inner peripheral surface side is small, the position to be loosely fitted is set. The degree of treatment differs depending on the position, the hardness and the case hardening depth vary depending on the position, and the quality of the heat treatment varies, and the inner diameter also varies. Therefore, for products to be heat-treated for which the hardness of the inner peripheral surface, the case hardening depth, or the accuracy of the inner diameter is high, in order to eliminate these problems, a partitioning jig called a spacer is used between the products to be heat-treated. Is used to loosely fit into the loose fitting part, a horizontal bar supported by the tray is prepared, and each heat-treated product is laid horizontally on this horizontal bar. It takes a long time to set the product, and the space between the products to be heat-treated is wasted.
This also leads to an increase in the number of jigs to be managed, resulting in higher costs. In addition, in these methods, it is difficult to insert the spacer and support the horizontal bar, so that automation also has a problem.

The present invention has been made in view of the above-mentioned conventional problems, and is a heat-treated product having high requirements for hardness of the inner peripheral surface, hardening depth and inner diameter dimension accuracy. It is an object of the present invention to provide a heat treatment jig that can be set in a short time, does not cause a decrease in the number of loose fittings of the heat-treated product, and does not increase the number of jigs to be managed.

[0006]

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

[0007]

In the heat treatment jig of the present invention, the engaged portion of the vertical bar is configured to engage with at least three adjacent engaging portions of the tray, and the central axis of the loose fitting portion is the tray. Since it is located inside the stitch, the inner peripheral surface side of the heat-treated product communicates with a wide gap in the stitch of the tray through the loose fitting part, and the quenching medium flowing into the stitch of the tray is the heat-treated product. It is easy to flow to the inner peripheral surface side. For this reason, the inner peripheral surface side of the product to be heat-treated using such a heat treatment jig is processed to have the same hardness and hardening depth as the outer peripheral surface side. Further, since the amount of quenching medium flowing into the inner peripheral surface side is large, products to be heat treated using such a heat treatment jig can be loosely fitted regardless of whether the vertical rods are loosely fitted or not. It is processed uniformly regardless of the position, and there is no variation in hardness, case hardening depth, or inner diameter depending on the position.

[0008]

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 tray 1 in the form of stitches and a standing rod 2 erected on the tray 1.

As shown in FIG. 2, the tray 1 is the same as the conventional one. That is, the tray 1 is a plate having square stitches, has 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 upright bar 2 has a cross-shaped base portion 20 and fan-shaped protrusions on the back side from the respective tip ends of the base portion 20 at the apexes of the squares, respectively. 4 to engage 4 engaging holes 11
The engaged protrusions 21 of the book and the engaged protrusions 21 from the base 20
The other side, that is, the loose fitting portion 22 in which a cross-shaped skeleton 23 in the horizontal direction is connected in place while extending in a direction substantially perpendicular to the stitches.

The heat-treated products W are stacked on the base portion 20 of the vertical rod 2 so that a plurality of them are loosely fitted in the loose fitting portions 22, and the four heat-treated products W are loosely fitted into the four vertical rods 4. The engaged projections 21 are engaged with the four adjacent engaging holes 11 of the tray 1 mounted on the dolly or the like, and are subjected to heat treatment in a set-completed state shown in FIG. Then, the quenching medium M such as surrounding gas or quenching oil directly acts on the outer peripheral surface side of the upright bar 2, and as shown in FIG. 4, the tray 1 flows the quenching medium M into the stitches from below. Then, the quenching medium M in the stitch acts on the inner peripheral surface side of the upright bar 2 to heat-treat the article W to be heat-treated.

At this time, in this heat treatment jig, the engaged projections 21 of the upright bars 2 are engaged at the same time as the four adjacent engaging holes 11 in the tray 1, and the central axis O of the loose fitting portion 22. Is located inside the stitch of the tray 1. Therefore, the inner peripheral surface side of the article W to be heat treated is the base 20, the loose fitting portion 22, and the skeleton 2.
The quenching medium M flowing into the stitches of the tray 1 easily communicates with the inner peripheral surface of the article W to be heat-treated, because the quenching medium M flows into the stitches of the tray 1 with a wide gap. Therefore, the inner peripheral surface side of the product W to be heat treated employing this heat treatment jig is processed to have the same hardness and hardening depth as the outer peripheral surface side.
Further, since the amount of inflow of the quenching medium M to the inner peripheral surface side is large, the heat-treated product W employing such a heat treatment jig does not matter whether the vertical rods 2 to be loosely fitted are the same or different, and It is processed uniformly regardless of the position where it is loosely fitted, and there is no variation in hardness, case hardening depth, or inner diameter depending on the position. (Embodiment 2) As shown in FIGS. 5 and 6, this heat treatment jig is composed of a knitted tray 3 and an upright bar 4 erected on the tray 3.

As shown in FIG. 6, the tray 3 has a diamond-shaped plate shape, has circular engagement holes 31 at the respective vertex positions of each diamond, and is supported by a column (not shown). is there. As shown in FIGS. 5 (a) and 5 (b), the upright bar 4 is
A Y-shaped base portion 40, and three engagement members that fan-out from the respective tips of the base portion 40 to the back side at the vertex positions of the equilateral triangles and engage with the three adjacent engagement holes 31 in the tray 3. It has a mating protrusion 41 and a loose fitting portion 42 in which a Y-shaped skeleton 43 is connected in place in the horizontal direction while extending from the base portion 40 on the side opposite to the engaged protrusions 41, that is, in a direction substantially perpendicular to the stitches. It is a thing.

In this heat treatment jig, the three engaged projections 41 of the upright bar 4 are engaged with the three adjacent engagement holes 31 of the tray 3, and the heat treatment is performed in the state where the setting is completed as shown in FIG. Be served. Even when this heat treatment jig is adopted, the same operation and effect as those of the first embodiment can be obtained. (Example 3) This heat treatment jig employs the upright 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 as that of the first embodiment is used, and the detailed description is omitted.

The upright bar 5 has a substantially square base portion 50 having a circular hole in the center, and a fan-shaped projecting portion on the back side at each vertex of the square portion from each tip of the base portion 50. Four engaged projections 5 that engage with the engaging holes 11
1 and a cross-shaped skeleton 5 extending in the horizontal direction from the base portion 50 on the side opposite to the engaged protrusions 51, that is, in the direction substantially perpendicular to the stitches.
3 is a loose fitting portion 52 connected in place, and a cylindrical guide portion 53 protruding from the base portion 50 on the same side as the engaged protrusions 51.
With and.

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 W to be heat treated by the guide portion 53 of the upright bar 5, and the inner peripheral surface of the article W to be heat treated. The side can be heat-treated even more suitably. Other actions and effects can be obtained as in the first embodiment. In the heat treatment jigs of Examples 1 to 3, the vertical bars 2, 4,
Since the engaged projections 21, 41, 51 of 5 are three or four, it is possible to stand with only the standing rods 2, 4, 5.
Handling and stocking before and after heat treatment can be easily performed.

The vertical bars 2, 4, 5 in the heat treatment jigs of Examples 1 to 3 are three or four engaged projections 2.
The central axis O is positioned by 1, 41 and 51.
For this reason, the positioning is facilitated, so that the positioning mechanism can be omitted even when automation is intended. In addition, on the tops of these upright bars 2, 4, 5, as shown in FIG.
Like the conventional vertical bar 9 shown in FIG.
4 is not necessary, and it is not necessary to provide a steady rest jig (not shown) for supporting the receiving portion 94. Therefore, a larger number of articles W to be heat-treated can be loosely fitted to one of the vertical bars 2, 4 and 5 and the workability can be improved.

Further, in the vertical bar 9 in the conventional heat treatment jig shown in FIG. 8, the engaged projections 91 are erected when standing on the tray 8.
Since a full load acts on the engaged protrusion 91 and a small gap between the engaged protrusion 91 and the engaging hole 81 constantly applies bending stress to the engaged protrusion 91, metal fatigue of the engaged protrusion 91 causes the vertical bar 9 to move. Although the service life was short, in the vertical bars 2, 4, 5 in the heat treatment jigs of Examples 1 to 3, three or four engaged projections 2 were engaged.
The load is dispersed by 1, 41, 51, and a small gap between the engaged projections 21, 41, 51 and the engagement holes 11, 31 is provided by three or four engaged projections 21, 41, 51. By absorbing, bending stress does not act on the engaged projections 21, 41, 51, and the life is extended.

In the first to third embodiments, trays 1 and 3 are used.
The engaging holes 11 and 31 are adopted as the engaging portions of the vertical bar 2,
Although the engaged projections 21, 41, 51 are adopted as the engaged portions of Nos. 4 and 5, the engaging projections are adopted as the engaged portions of the tray 1, and the engaged holes are employed as the engaged portions of the upright bar 2. Can also be adopted.

[0019]

As described in detail above, in the heat treatment jig of the present invention, the engaged portion of the upright bar is configured to engage with at least three adjacent engaging portions of the tray at the same time. The central axis of the loose fitting portion is located inside the stitch of the tray. Therefore, if this heat treatment jig is adopted, it is possible to process the inner peripheral surface side of the heat-treated product to the same hardness and hardening depth as the outer peripheral surface side without adopting the conventional method. it can. In addition, the product to be heat treated that uses this heat treatment jig is
Without adopting the conventional method, regardless of whether the vertical bars that are loosely fitted are the same or not, and they are uniformly processed regardless of the position where they are loosely fitted, the hardness depending on the position, and the case hardening depth. There is no variation in inner diameter.

Therefore, if this heat treatment jig is adopted, it is not necessary to adopt the conventional method, so that the products to be heat treated can be set in a short time and the number of loose fittings of the products to be heat treated can be reduced. There is no need to increase the number of jigs to be managed. Therefore, by adopting this heat treatment jig, it is possible to perform heat treatment at a low cost even for a heat-treated product whose inner peripheral surface hardness, hardening depth and inner diameter dimension accuracy are high.

[Brief description of drawings]

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

2 is a plan view of a tray in the heat treatment jig of Example 1. FIG.

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 Example 1.

FIG. 4 is a sectional view taken along the 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 and (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 Example 2.

FIG. 7 relates to a vertical bar in the heat treatment jig of Example 3,
(A) is a side view and (b) is a plan view.

FIG. 8 is a side view of a vertical 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.

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 ... Engagement hole (engagement part) 2, 4, 5 ... Stand bar 21, 41, 51 ... Engagement projection (engagement part) 22, 42, 52 ... Free fitting part O ... central axis M ... quenching medium W ... heat treated product

Claims (1)

[Claims] 1. A tray in which the stitches are polygonal stitches, each of which has an engaging portion at each vertex of the polygon, and a quenching medium flows into the stitches; and the engaging portion of the tray. A heat treatment treatment comprising an upright bar having an engaged portion to be engaged with and a loose fitting 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. In the tool, the upright bar is configured such that the engaged portion is configured to engage with at least three adjacent engaging portions at the same time, and the central axis of the loose fitting portion is located inside the stitch of the tray. A heat treatment jig characterized in that