JP4164299B2 - Casting heat treatment jig - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is formed in a substantially box shape from a bottom wall portion in which a plurality of vertically long hexagonal long holes having a honeycomb structure are formed, and a side wall portion, in which a product to be heat treated is housed, and heat treatment The present invention relates to a casting heat treatment jig that can be placed in a heating furnace.
[0002]
[Prior art]
Various heat treatment jigs in which a plurality of products to be heat treated are stored or placed have been proposed. For example, a heat treatment jig having an improved frame structure stacked in a plurality of stages is disclosed in Japanese Utility Model Laid-Open No. 60-71657, and a heat treatment jig devised for holding a workpiece that is a heat treated product is a real heat treated jig 63. -Proposed by No. 13985. By the way, there is a workpiece having a small diameter, such as a pin, washer, or bolt, or a short accessory, but a heat treatment jig having an improved frame structure as described in the aforementioned publication, Alternatively, small workpieces cannot be processed with a heat treatment jig improved to hold a workpiece having a special shape.
[0003]
Therefore, the present applicant has proposed a casting heat treatment jig capable of heat treating small articles by Japanese Patent Laid-Open No. 8-159672. This casting heat treatment jig is generally formed in a box shape from a bottom wall portion and a side wall portion. The bottom wall portion and the side wall portion are integrally formed by a precision casting method so as to have a number of wire mesh-like through holes from rod-like elements. These through holes are formed in a polygonal shape, and at least one side thereof is 15 mm or less.
[0004]
[Problems to be solved by the invention]
The above-mentioned casting heat treatment jig proposed by the present applicant is integrally formed into a wire mesh by casting so that the bottom wall portion and the side wall portion have a large number of through holes from rod-shaped elements, and these through holes Is polygonal, and at least one side thereof is 15 mm or less, so that it has a feature that small items such as pins, bolts and washers can be heat-treated despite being made of casting. Moreover, since it is manufactured by one type of manufacturing method called casting, the number of manufacturing steps is small and it can be obtained at low cost. Furthermore, since it is cast and formed of the same material, that is, since a stainless steel wire mesh is not used as in the prior art, it has a feature that distortion, deformation, breakage, and the like hardly occur. Therefore, a casting heat treatment jig having a long service life can be obtained. Since the casting heat treatment jig proposed by the present applicant has such characteristics, it is still effectively used in the metal processing field.
However, since the heat treatment jig is taken in and out of the heating furnace and receives frequent thermal stress, a heat treatment jig that is more resistant to thermal deformation is also required.
Accordingly, an object of the present invention is to provide a heat treatment jig that is less likely to be deformed, has a high strength, and is light in weight even though a small object such as a pin can be heat treated. Another object of the present invention is to provide a heat treatment jig that is convenient for use in a plurality of stages in addition to the above object.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, the heat treatment jig according to the present invention may be a general sand mold casting so that it substantially has a box shape from the bottom wall portion and the side wall portion. Molded integrally. At this time, a plurality of holes are formed in the bottom wall portion so that the product to be heat-treated is uniformly heated. Desirably, a plurality of holes are also formed in the side wall portion. And according to this invention, the hole of a bottom wall part is formed as a hexagonal elongate hole of the honeycomb structure which exhibits a hexagon seeing planarly. More specifically, a plurality of hexagonal long holes having a honeycomb structure are not exact hexagonal holes, and two of the six sides forming the holes are opposed to the other sides. It is formed so as to be long and long.
[0006]
As described above, the bottom wall portion in which a plurality of vertically long hexagonal long holes having a honeycomb structure is formed is preferably divided into four sections in view of a plurality of sections, production cost, and the like. It is divided. The hexagonal long holes in each section are oriented in the same direction and are arranged adjacent to the side of the vertically long hexagonal long hole in the adjacent section. Desirably, alignment ribs as strength members are integrally cast on the four corners of the side wall portion thus configured. Furthermore, a support column is integrally cast on the bottom wall portion.
[0007]
Thus, in order to achieve the object of the present invention, the invention according to claim 1 is substantially a box made up of a bottom wall portion in which a plurality of vertically long hexagonal long holes having a honeycomb structure are formed, and a side wall portion. A casting heat treatment jig that is formed into a shape, accommodates an object to be heat treated therein, and is placed in a heating furnace for heat treatment. The plurality of vertically long hexagonal slots in each section are oriented in the same direction, and are adjacent to each other substantially perpendicular to the plurality of vertically long hexagonal slots in the adjacent section. ing. According to a second aspect of the present invention, a plurality of side windows are formed in the side wall portion of the first aspect, and alignment ribs for alignment and reinforcement when stacked are formed at the corner portions of the side wall portion. The invention according to claim 3 is integrally cast, and in the bottom wall according to claim 1 or 2, when the stack is stacked, a column supporting a cast heat treatment jig thereon is integrally cast. Has been.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
First, the shape and structure of the casting heat treatment jig G according to the present embodiment will be described, and then the manufacturing method or casting method will be described. As shown in FIG. 1A, the casting heat treatment jig G has a substantially rectangular bottom wall portion 1 having a side of about 570 mm and a side wall having a height of about 60 mm. The part 10 is formed in a relatively shallow box shape. According to the embodiment shown in FIG. 1, the bottom wall 1 having such a size is apparently divided into first to fourth sections 1a to 1d. In each of the sections 1a to 1d, a plurality of vertically long hexagonal long holes 2, 2,... Having a honeycomb structure are formed. Further, according to the present embodiment, the first to fourth side walls 10a to 10d constituting the side wall portion 10 are also shown in FIGS. 1 (a) and 2 (b). A plurality of sidewall windows 11, 11,... Exhibiting a substantially square shape are opened.
[0009]
2A is a plan view of the bottom wall portion 1, and FIG. 3A is an enlarged view of a part thereof. In particular, as shown in FIG. The rectangular long hole 2 is formed in a honeycomb shape from three pairs of bottom ribs 3, 3, 4, 4,. In the present embodiment, the length of the first pair of bottom ribs 3 and 3 is about 30 mm, and the length of the other pair of bottom ribs 4 and 4 is selected to be 12 mm. The ribs 3 and 3 are longer than the other pairs of bottom ribs 4 and 4. Therefore, the hexagonal long hole 2 is vertically long, and the length in the major axis direction is 45 mm and the minor axis direction is 18 mm. As shown in FIG. 3B, the sizes of the bottom ribs 3 and 4 are selected such that the width W is 3 mm and the height H is 7 mm. The top is marked with an R of 1.5. Therefore, the workpiece to be heat-treated is supported in line contact with the tops of these bottom ribs 3, 4,. In the present embodiment, auxiliary ribs 3 ′ and 3 ′ are integrally formed on both sides of the first pair of bottom surface ribs 3 and 3. These auxiliary ribs 3 ′ and 3 ′ prevent a small work from falling off the casting heat treatment jig G.
[0010]
The plurality of hexagonal long holes 2, 2,... As described above face the same direction in each of the sections 1a to 1d. More specifically, the hexagonal long holes 2, 2,... In the first compartment 1a are similarly arranged in the second compartment 1b so that their longitudinal axes are parallel to the first side wall 10a. The hexagonal long holes 2, 2,... Are formed so as to face in the same direction below so that the longitudinal axis thereof is parallel to the second side wall 10b. In other words, the plurality of vertically long hexagonal long holes 2, 2,... Make a round by changing the direction by 90 degrees for each of the sections 1a to 1d. In this way, in the adjacent portions whose directions are changed by 90 degrees in each of the sections 1a to 1d, as shown in FIG. 2 (a), the hexagonal oblong holes 2, 2,. 1 bottom ribs 3 and 3 are about half the length. One bottom rib 3 is integrated with the first bottom rib 3 of the adjacent hexagonal long hole 2, and the other bottom rib 3 is a joint between the first bottom rib 3 and the other bottom rib 4. Is integrated. Thereby, the 1st-4th divisions 1a-1d comprise the one continuous bottom wall part 1. FIG.
[0011]
In the four corners of the first to fourth side walls 10a to 10d configured as described above, as shown in FIGS. 1 and 2, the side walls 10a to 10d are connected at right angles, Alignment ribs 15, 15,... Projecting slightly upward are integrally formed downward in the vertical direction. Corresponding to these alignment ribs 15, 15,..., Concave stoppers 16, 16,... Are formed at the lower four corners of the first to fourth side walls 10 a to 10 d. Therefore, it is possible to stack the heat treatment jigs G in a plurality of stages by positioning so that the positioning ribs 15, 15,... Enter the concave stoppers 16, 16,.
[0012]
In the present embodiment, one support column 17 is integrally cast at the substantially central portion of the bottom wall portion 1. As shown in FIG. 1 (a), FIG. 2 (b), etc. , the support column 17 extends over the plurality of bottom ribs 3, 4,. It is molded integrally and rises upward from it. The diameter of the base of the column 17 is large, and the upper diameter is small. And the height is somewhat higher than the side walls 10a to 10d. Corresponding to the column 17, a recess 18 is formed on the lower surface of the bottom wall 1 as shown in FIG. Therefore, when the casting heat treatment jig G is stacked in a plurality of stages, the columns 17 and the recesses 18 are aligned, and the upper casting heat treatment jig G is supported by the support pillar 17 at the center thereof. become.
[0013]
The casting heat treatment jig G according to the present embodiment also has a side window in which the bottom wall portion 1 has a large number of hexagonal long holes 2, 2,. Since 11, 11,... Are formed, it is apparent that small workpieces such as pins can be heat-treated in the same manner as the conventional casting heat treatment jig described above.
[0014]
When a heat treatment jig G having a structure according to the present embodiment was prototyped and tested, it was found that the amount of thermal deformation was extremely small compared to the conventional one. The reason is considered as follows. That is, although the honeycomb structure has high strength and is resistant to deformation, according to the present embodiment, the bottom wall portion 1 has a plurality of vertically long hexagonal long holes 2, 2,... For each of the sections 1a to 1d. Are formed so as to make a round around 90 degrees, so that the long first bottom ribs 3, 3,... Constituting the hexagonal long holes 2, 2,. , 4,... Have a degree of freedom, and thermal stress is mainly absorbed by the first bottom ribs 3, 3,. The stress in the longitudinal direction acting on the first bottom ribs 3, 3,... Mainly acts on the joint portion between the first bottom rib 3 and the other bottom rib 4 in the adjacent section. And it is absorbed. Thus, according to this Embodiment, the bottom wall part 1 is divided | segmented into four divisions 1a-1d, and the stress in each division is disperse | distributed in order to an adjacent division, and goes around. Thereby, it is thought that thermal deformation is prevented.
[0015]
In addition, according to the present embodiment, the hexagonal long holes 2, 2,... Have a honeycomb structure and have a large number of contact points, so that the rigidity is increased as compared with the conventional heat treatment jig having large through holes. ing. Further, according to the present embodiment, since the alignment ribs 15, 15,... Are provided, the strength or rigidity of the casting heat treatment jig G is improved. 15 are formed in the four corners of the cast heat treatment jig G in the vertical direction, so that uniform heat treatment can be performed without adversely affecting the workpiece when heated. Furthermore, according to the present embodiment, since the support pillars 17 are provided, a work having a large weight can be put and can be put in a heat treatment furnace. Further, according to the present embodiment, the first bottom ribs 3, 3,... Constituting the hexagonal long hole holes 2, 2,... Are longer than the other bottom ribs 4, 4,. Therefore, it is lighter than the area of the hexagonal long holes 2, 2,.
[0016]
The present invention is not limited to the above embodiment and can be implemented in various forms. For example, although the bottom wall 1 is divided into four first to fourth sections 1a to 1d in the above-described embodiment, two or more pieces can be implemented. FIG. 3C is a schematic plan view showing an embodiment in which the bottom wall portion 1 ′ is apparently divided into first to sixth six sections 1a ′ to 1f ′. In FIG. ,... Indicate a plurality of vertically long hexagonal long holes, but as shown in this figure, the plurality of vertically long hexagonal long holes 2 ′, 2 ′,. The direction is changed by 90 degrees every '~ 1f'. Therefore, the effects as described above can be obtained even if the above-described method is implemented. Further, it is obvious that the size of the casting heat treatment jig G, the width W of the bottom ribs 3, 4,..., The height H, etc. are not limited to the above embodiment.
[0017]
Next, a casting method of the casting heat treatment jig G will be described.
[Preparation of casting material]
The casting material applied in this example is a heat-resistant alloy having a two-phase structure of austenite and austenite + ferrite containing Fe, Ni, Cr, Co, Mo, W, Nb, etc., typically JIS SCH13, SCH15 and SCH24. When manufactured with these alloys, a jig having excellent oxidation resistance, hot strength, and the like and less thermal strain can be obtained.
[0018]
[Casting jig]
The casting heat treatment jig G described above is cast by the precision casting method using the casting material prepared as described above. As the precision casting method, there are known casting methods using disappearance models such as investment method (lost wax method), ceramic mold method, plaster mold method, etc., or shell mode method. can do. For example, make a so-called disappearance model that is the same shape as the heat treatment jig G with wax, synthetic resin, etc., coat a ceramic refractory around this model, make a ceramic mold that only thinly surrounds it, and Elution or burning disappears to make a mold. Next, molten metal is poured into this mold to cast a heat treatment jig G.
[0019]
In the above-described embodiment, the heat treatment jig G is formed by integrally casting the substantially square bottom wall portion 1 and the relatively shallow side wall portion 10, but when producing a relatively large jig, The bottom wall part 1 and the side wall part 10 can be divided into two to three parts, cast, and integrated by welding. Even if manufactured in this way, since the same material is cast, that is, a stainless steel wire mesh is not used, it is obvious that the same effect as the above-described embodiment can be obtained. It is also clear that it can be produced by sand mold casting other than precision casting.
[0020]
【The invention's effect】
As described above, the casting heat treatment jig according to the present invention is formed in a substantially box shape from the bottom wall portion in which a plurality of vertically long hexagonal elongated holes having a honeycomb structure are formed, and the side wall portion, The bottom wall portion is apparently divided into a plurality of sections, and the plurality of vertically long hexagonal slots in each section face the same direction, and the plurality of vertically long hexagonal slots in the adjacent section Adjacent to each other at a substantially right angle, the thermal stress is absorbed primarily by the longer element making up the elongated hexagonal slot, and the hexagonal slot in the adjacent compartment. Acts on the constituent elements. Therefore, an effect peculiar to the present invention that the amount of thermal deformation of the casting heat treatment jig according to the present invention is extremely small can be obtained. Further, according to another invention, a side wall window is also formed on the side wall, an alignment rib for alignment and reinforcement when stacked, and a support column are integrally cast on the bottom wall. Therefore, even if it is stacked in a plurality of stages, the heat is good, and the effect of uniformly heat-treating a large amount of non-heat-treated products at once can be further obtained.
[Brief description of the drawings]
FIG. 1 is a view showing a casting heat treatment jig according to an embodiment of the present invention, in which (a) is a perspective view schematically showing the whole, and (b) is an enlarged part of a corner portion. FIG.
FIGS. 2A and 2B are views showing a casting heat treatment jig according to an embodiment of the present invention, in which FIG. 2A is a plan view and FIG. 2B is a side view showing a part thereof in cross section.
FIG. 3 is a view showing a casting heat treatment jig according to an embodiment of the present invention, in which (a) is a partially enlarged plan view of a bottom wall portion, and (b) is in the roll direction in (a). The viewed sectional view, (c) is a plan view schematically showing another embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Bottom wall part 1a-1d 1st-4th division 2 Hexagonal elongate hole 3 1st bottom face rib 10 Side wall part 10a-10d 1st-4th side wall 15 Alignment rib 17 Support | pillar G Casting jig for heat treatment

Claims (3)

A bottom wall portion having a plurality of vertically long hexagonal elongated holes having a honeycomb structure and a side wall portion are formed in a substantially box shape, in which a product to be heat treated is housed, and a heating furnace for heat treatment A heat-treating jig made of cast material,
The bottom wall portion is apparently divided into a plurality of sections, and the plurality of vertically long hexagonal slots in each section face the same direction, and the plurality of vertically long hexagonal slots in the adjacent section A casting heat treatment jig characterized by being adjacent to each other substantially at a right angle to each other. A plurality of side windows are formed in the side wall portion according to claim 1, and a positioning rib for positioning and reinforcing when stacked is integrally cast at a corner portion of the side wall portion . Heat treatment jig. 3. A cast heat treatment jig, wherein a support for supporting a cast heat treatment jig thereon is integrally cast on the bottom wall portion according to claim 1 when stacked.

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