JP2002226909A - Tool for heat treatment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tool for a heat treatment giving little burning problem, although inserting parts can effectively use even existing columnar supporting rods without disposing of it. SOLUTION: This tool for heat treatment is constituted of a tray (1) having a plurality of through-holes (4, 4,...) opened and a plurality of supporting rods (10, 10,...) inserted into these through-holes (4, 4,...). The tray (1) is formed in almost flat plate shape from a grid body with a precision casting, and in the inner peripheral surface of the through-hole (4, 4,...), a plurality of recessed grooves (5, 5,...) or projecting lines (6, 6...) having prescribed width, are formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tray having a plurality of through holes, and a plurality of trays each having an insertion portion inserted and mounted in a selected through hole of the tray. The work piece is hung or placed above the tray by the support, and a work receiver, a spacer, a shelf, and an auxiliary member such as a vibration stopper set with the support as a support. Further, the present invention relates to a heat treatment jig which is to be put into a heat treatment heating furnace.

[0002]

2. Description of the Related Art Various heat treatment jigs for accommodating or placing a plurality of heat-treated articles have been proposed. For example, the jig for heat treatment in which the frame structure to be stacked in plural stages is improved is disclosed in Japanese Utility Model Laid-Open No. 60-71657. No. 13985 and the like. Further, a heat treatment jig as shown in FIG. 3 is also known. In other words, the tray 30 is made up of a cast tray 30 having a flat plate shape and a plurality of columns 35, 35,..., The tray 30 is provided with a plurality of through holes 31, 31,. .. Are also known. The heat treatment jig is provided with an auxiliary member including, for example, spacers 32, 32,..., Shelf members 33, 33,.

Therefore, as shown in FIG.
An appropriate number of columns 35, 35,
Are assembled, and the shelf members 33, 33,... Are assembled via the spacers 32, 32,.
Are attached to the shelf member 33,
33, can support it. .. Can be put in a heating furnace for heat treatment together with the tray 30 and subjected to heat treatment as is well known in the art.
Although not shown in the figure, a work receiver is attached to the tray as described above, a relatively long work is set up in the work receiver in the axial direction, and the work is mounted above the support column by a vibration stopper. The ends can be fixed and placed in a heating furnace for heat treatment.

[0004]

As described above, even with the conventional heat treatment jig, by inserting a plurality of columns into appropriate positions and employing appropriate auxiliary members,
Various shapes of workpieces can be heat treated. Also,
There is also an advantage that the service life is long because the tray is made of cast material.
By the way, in order to heat-treat workpieces of various shapes with a predetermined tray, as described above, auxiliary members such as a work receiver, a spacer, a support member, and a vibration-prevention, which are used together with the tray, must be replaced with those corresponding thereto. Therefore, it may be necessary to extract the support from the tray and change the insertion position according to the type of the workpiece to be heat-treated.
It may also be necessary to remove the post that has been heat treated and remove the struts when attaching a new workpiece.
By the way, even if the heat treatment temperature is relatively low, such as 950 ° C., the insertion portion of the support may stick to the inner peripheral surface of the through hole of the tray and may be difficult to remove. Therefore, a plurality of projections are provided in the axial direction on the outer peripheral surface of the insertion portion of the column to reduce the contact area between the insertion portion of the column and the inner peripheral surface of the through hole of the tray, thereby making the column harder to seize. There are also proposals.
However, the number of columns having such a structure is small in number on the market, and the column-shaped insertion column that can be obtained structurally at low cost is more practically used in practice.

[0005] It is considered that seizure can be prevented by elaborating the shape of the through hole of the tray even with the above-described insertion portion even with a columnar support. However, since the through hole is formed in the tray by casting. Because a complicated core is required in shape, the casting cost is high, and accurate seizure prevention means cannot always be formed, so trays with straight through holes that are convenient for casting are often used. ing. And it is causing the burn-in problem.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described conventional situation, and has a heat treatment with little seizure despite the fact that the existing insertion column can be effectively used without discarding it. It is another object of the present invention to provide a heat treatment jig which is lightweight but has high strength and a high heat treatment effect. Another object of the present invention is to provide a heat treatment jig having a plurality of ridges, which can be similarly applied to an existing column, and which has a high heat treatment effect.

[0007]

According to the present invention, in order to achieve the above object, a precision casting method is applied to tray casting. As a result, an accurate seizure prevention means having a predetermined width, that is, a concave groove or a ridge is formed on the inner peripheral surface of the through hole of the tray. Further, with respect to a column having a ridge or a groove formed in the insertion portion, a groove or a ridge different in width from the ridge or the groove is formed in the through hole of the tray. This provides a heat treatment jig that has little seizure not only on newly provided columns but also on existing columns. Thus, in order to achieve the above object, the invention according to claim 1 includes a tray provided with a plurality of through holes, and a selected through hole of the tray,
The insertion portion is inserted, consists of a plurality of columns that are adapted to be mounted, the column, and a work receiver, a spacer, a shelf, a support member such as a vibration stop, which is set with the column as a support, A heat treatment jig in which the article to be heat-treated is suspended or placed above the tray, and is placed in a heating furnace for heat treatment, wherein the tray comprises:
The lattice is formed by precision casting so as to have a substantially flat shape, the through-hole is formed through the flat portion, and a plurality of grooves having a predetermined width are formed in the inner peripheral surface thereof in the penetrating direction. Alternatively, it is configured such that a ridge is formed. The invention according to claim 2 is configured such that the outer peripheral surface of the insertion portion of the column applied to the tray according to claim 1 has a cylindrical shape, and the invention according to claim 3 is according to claim 1. A plurality of ridges or grooves having a predetermined width are formed on the outer peripheral surface of the insertion portion of the column applied to the tray described in the above, and the width of the groove or the ridge of the through hole of the tray is equal to the width of the column. Different from the width of the ridges or grooves, when inserting and mounting the insertion portion of the support into the through hole of the tray, the outer peripheral surface of the insertion portion of the support and the inner peripheral surface of the through hole of the tray. Are configured to make line contact at a plurality of locations.

[0008]

Embodiments of the present invention will be described below. First, the shape and structure of the heat treatment jig according to the present embodiment will be described, and then the manufacturing method will be described. Tray 1 of heat treatment jig according to the present embodiment
As shown in FIG. 1A, is composed of a substantially rectangular plate-like lattice body having a length A of, for example, 456 mm, a width B of 606 mm, and a thickness of 50 mm. That is, in a state where the ends of the plurality of main ribs 2, 2,... Are integrated with each other, the main ribs 2, 2,. Main rib 2,
The width of 2,... Is, for example, 6 mm, and the thickness is 50 mm, as described above, in a plate shape. As a result, the section modulus is increased. As described above, according to the present embodiment, since the main ribs 2, 2,... Having a large section modulus are formed in a lattice shape, the tray 1 maintains a predetermined strength and is reduced in weight. In addition, tray 1 with small heat capacity
It is with.

The tray 1 has a diameter of, for example, 20
, the main ribs 2, 2,... are arranged in a predetermined pattern in consideration of convenience of use.
The auxiliary ribs 3, 3,... Are connected between the auxiliary ribs 3, 3,.
Are formed so as to penetrate through. In the embodiment shown in FIG. 1B, for example, twelve concave grooves 5 having a predetermined width w are formed on the inner peripheral surfaces of these through holes 4, 4,.
.. Or the ridges 6, 6,... Are formed in the axial direction.

FIG. 2 shows a conventional post or a post 10 according to an embodiment of the present invention. This support 10 is inserted into the through hole 4 of the tray 1 as shown in FIG.
An insertion portion 11 of 9.7 mm, a column portion 12 having a length of 510 mm, and a flange portion 13 acting as a stopper when inserted into the through hole 4 of the tray 1 are integrally formed by, for example, casting. I have. The insertion portion 11 is formed in a columnar shape, and the support portion 12 is formed in a cross shape to reduce the weight and improve the convection of the atmosphere in the furnace, as shown in FIG.

Next, an example of use of the above embodiment will be described. The number of columns 10, 10,... To be used and auxiliary members such as a work receiver, a spacer, a shelf member, and a vibration stop are appropriately selected depending on the shape and structure of the work to be heat-treated. Then, the insertion portions 11, 11,... Of the columns 10, 10,... Are inserted into predetermined through holes 4, 4,. The mounted state is shown in FIG. Thereby, the pillar 1
The outer peripheral surfaces of the insertion portions 11 at 0, 10,... Are in line contact with the top surface of the ridges 6 of the through holes 4 of the tray 1 at a plurality of positions, and stand on the tray 1. A plurality of works are sequentially placed or suspended in the space above the tray 1 while setting the auxiliary member from below. Next, it is put into a heating furnace for heat treatment together with the tray 1 and heated to a predetermined temperature in a predetermined atmosphere. The tray 1 is formed in a lattice shape, and the columns 12, 1 of the columns 10, 10,.
Are formed in a cross shape, the furnace atmosphere such as nitriding or carburizing heats the workpiece to be heat-treated directly and in a short time. Thereby, the work is uniformly heated and heat-treated as conventionally known.

When it is necessary to remove a heat-treated work or heat-treat a work having another shape,
The support members 10, 10,... Are sequentially removed from the upper auxiliary member.
From the through holes 4, 4,... Of the tray 1. And then
.. Are reinserted and mounted in the necessary through holes 4, 4,..., The work is mounted as described above, and heat treatment is performed.

According to the present embodiment, the columns 10, 10,.
The insertion portions 11, 11,... Are cylindrical.
Since the plurality of grooves 5, 5,... Or the ridges 6, 6,... Are formed on the inner peripheral surfaces of the through holes 4, 4,. , 11 are in line contact with the ridges 6, 6,... Of the through holes 4, 4,. Therefore, for example, 1100 ° C
Even when the heat treatment is performed at such a high temperature, the insertion portions 11, 11 of the columns 10, 10,... Do not stick to the inner peripheral surfaces of the through holes 4, 4,.

It is clear that the through holes of the tray 1 can be implemented in various forms without being limited to the above-described embodiment. For example, as shown in FIG. 1 (c), it is also possible to form the concave grooves 5 ', 5',... At positions corresponding to the auxiliary ribs 3, 3,. With such an implementation, it is possible to obtain an effect of preventing a cavity from being formed in a thick portion of the auxiliary ribs 3, 3,. In addition, the concave groove 5 ',
Obviously, another groove can be further formed between 5 ′,.

In the above embodiment, the columns 10, 10,...
Are formed in a columnar shape, but a column having a plurality of ridges or grooves formed in the outer peripheral surface of the insertion portion in the axial direction is also described in the section of the prior art. As you can see, the number is small but commercially available. When applied to these columns, the width of the groove or groove formed on the inner peripheral surface of the through hole of the tray is formed so as to be different from the width of the groove or groove of the insertion portion of the column. Then, when the insertion portion of the support is inserted into the through hole of the tray, the ridges or grooves of the insertion portion of the support do not engage with the grooves or protrusions of the through hole of the tray, and come into line contact. As a result, burn-in is prevented as described above.

Next, a method of casting a tray will be described. [Preparation of casting material] The casting material applied in this embodiment is as follows.
A heat-resistant cast steel alloy having a two-phase structure of austenitic and austenitic + ferrite containing Fe, Ni, Cr, Co, Mo, W, Nb, etc., typically JIS SC
H13, SCH15 and SCH24. When these alloys are used, a tray having excellent oxidation resistance, hot strength and the like and low thermal strain can be obtained.

[Tray Casting] Using the casting material prepared as described above, the above-mentioned casting tray is cast by a precision casting method. As a precision casting method, a casting method using a vanishing model such as an investment method (lost wax method), a ceramics molding method, a plaster molding method, or a shell mode method is known. Can be cast. For example, make a so-called vanishing model with the same shape as the tray using wax, synthetic resin, etc. And make a mold.
Next, a molten metal is poured into the mold to cast a tray.

In the above-described embodiment, the tray is integrally cast from a substantially square lattice-like body.
It can be divided into individual pieces, cast, and integrated by welding. Since the same material is used for casting in this way, it is clear that the same effects as those of the above-described embodiment can be obtained.

[0019]

As described above, according to the present invention, the tray constituting the jig for heat treatment is formed by precision casting so as to have a substantially flat shape from a lattice body, and the through-hole is formed in the flat portion. And a plurality of grooves or ridges having a predetermined width are formed in the inner peripheral surface thereof in the penetrating direction, or the width of these grooves or ridges is Since the width of the ridges or grooves of the insertion portion is different from that of the insertion portion, the outer peripheral surface of the insertion portion of the column hardly seizes on the inner peripheral surface of the through hole of the tray, even when used in a heating furnace for heat treatment at a relatively high temperature, The effect peculiar to the present invention that the support pillar can be easily removed from the tray is obtained. In addition, since the tray is formed of a lattice, the rigidity is high but the weight is low, and the heat capacity is small, so that the effect of not lowering the ambient temperature even when the tray is placed in a heating furnace can be obtained.

[Brief description of the drawings]

FIG. 1 is a view showing a tray according to an embodiment of the present invention, in which (a) is a plan view showing the entirety, (b) is an enlarged plan view showing an embodiment of a through hole, and (c). FIG. 4 is an enlarged plan view showing another embodiment of a through hole.

FIGS. 2A and 2B are diagrams showing a support according to the embodiment of the present invention or a conventional support, wherein FIG. 2A is a front view showing the entire support by cutting a part of the support, and FIG. (A) is a cross-sectional view taken along a roll, and (c) is a front view showing a state of insertion and mounting of the columns together with a part of the tray.

FIG. 3 is a perspective view showing a use state of a conventional heat treatment jig.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tray 2 Main rib 3 Auxiliary rib 4 Through-hole 5 Concave groove 6 Convex line 10 Prop 11 Insert part Reference number TAIHEI054

Claims (3)

[Claims] 1. A tray having a plurality of through-holes, and a plurality of columns having insertion portions inserted and mounted in selected through-holes of the tray, An article to be heat-treated is suspended or placed above the tray by the support and a work receiver, a spacer, a shelf, and an auxiliary member set with the support as a support, and a heating furnace for heat treatment A heat treatment jig adapted to be put into the tray, wherein the tray is formed by precision casting so as to have a substantially flat plate shape from a lattice body, and the through-hole is formed through the flat plate portion. A jig for heat treatment, wherein a plurality of grooves or projections having a predetermined width are formed in the inner peripheral surface thereof in a penetrating direction. 2. A heat treatment jig, wherein an outer peripheral surface of an insertion portion of a column applied to the tray according to claim 1 has a cylindrical shape. 3. A plurality of ridges or grooves having a predetermined width are formed on an outer peripheral surface of an insertion portion of a column applied to the tray according to claim 1, wherein the ridges or grooves have through holes in the tray. The width of the ridge is different from the width of the ridge or groove of the support,
Accordingly, when the insertion portion of the support is inserted into and attached to the through hole of the tray, the outer peripheral surface of the insertion portion of the support and the inner peripheral surface of the through hole of the tray are in line contact with each other at a plurality of locations. .