JP2018128203A - Heat treatment device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To cool a treatment object in a heat-insulated chamber more efficiently than ever.SOLUTION: A heat treatment device performs heat treatment by heating and cooling a treatment object contained in a heat-insulated chamber, and comprises a heat insulation body having a hollow structure forming the heat-insulated chamber and spaces formed inside, and a fluid setting device setting the filled state of a fluid to the space. The multiple spaces are provided so as to surround the treatment object.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a heat treatment apparatus.

  Patent Document 1 listed below discloses a heat treatment apparatus in which a heat insulating chamber formed of a predetermined heat insulating material is provided inside a heating chamber, and a heater that is a heating element is provided inside the heat insulating chamber. This heat treatment apparatus heat-treats the object to be processed accommodated in the heat insulation chamber by heating the object to be processed with a heater and gas-cooling the heated object to be processed. In addition, the heat processing apparatus provided with the above heat insulation chambers is disclosed by many patent documents other than patent document 1. FIG.

JP 2007-092137 A

  By the way, the said heat insulation chamber is provided in order to heat a to-be-processed object efficiently, and exhibits desired heat insulation performance by setting a heat insulating material to predetermined thickness. However, the heat insulation chamber hinders the object to be processed from being cooled due to its heat insulation performance. That is, since this heat insulation chamber has a performance (heat retention performance) for keeping the object to be treated warm, it is difficult to efficiently cool the object to be treated due to the insulation performance.

  This invention is made | formed in view of the situation mentioned above, and aims at cooling the to-be-processed object in a heat insulation chamber more efficiently than before.

  In order to achieve the above object, in the present invention, as a first solving means related to a heat treatment apparatus, a heat treatment apparatus for heat treatment by heating and cooling an object accommodated in the heat insulation chamber, the heat insulation chamber And a fluid setting device that variably sets the filling state of the fluid in the space, and a plurality of the spaces are provided so as to surround the object to be processed. Adopting the means of being.

  In the present invention, as a second solving means related to a heat treatment apparatus, in the first solving means, the fluid setting device collects a fluid from the space during the heat treatment of the workpiece, A means of supplying a fluid to the space during the cooling process is adopted.

  In the present invention, as a third solving means relating to the heat treatment apparatus, a means is adopted in which the reinforcing member is provided in the space in the first or second solving means.

  In the present invention, as a fourth solving means relating to the heat treatment apparatus, a means is adopted in which the reinforcing member is a granular heat insulating material in the third solving means.

  In the present invention, as a fifth solving means relating to the heat treatment apparatus, in the first to fourth solving means, a means is provided in which a guide member for guiding the flow of the fluid is provided in the space. To do.

  According to the present invention, since the fluid filling state is variably set by the fluid setting device, it is possible to variably set the heat transfer coefficient of the heat insulator during heat insulation and during cooling of the workpiece. It is. Therefore, according to this invention, it is possible to cool the to-be-processed object in a heat insulation chamber more efficiently than before.

1 is a front sectional view showing an overall structure of a heat treatment apparatus according to an embodiment of the present invention. It is an AA arrow directional view in the above-mentioned front sectional view. It is the front sectional view (a) which shows the detail of the heat insulation board in one Embodiment of this invention, and a BB arrow directional view (b). It is a flowchart which shows operation | movement of the heat processing apparatus which concerns on one Embodiment of this invention. It is a schematic diagram which shows the performance of the heat insulation board in one Embodiment of this invention. It is a cross-sectional view which shows the filling state of the granular reinforcement material of the heat insulation board in one Embodiment of this invention.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
As shown in FIGS. 1 and 2, the heat treatment apparatus according to the present embodiment is an apparatus for performing heat treatment by heating and cooling the workpiece X accommodated in the heat insulation chamber R. The housing 1, the door 2, Clamp ring 3, four legs 4, mounting table 5, wheel 6, heat insulator 7, hearth 8, heating element 9, cooling fan 10, fan motor 11, cooling coil 12, upper cylinder 13, lower cylinder 14 and gas setting Device 15 etc. are provided.

  Although not shown in FIGS. 1 and 2, the heat treatment apparatus includes a vacuum pump for bringing the heat insulation chamber R into a vacuum state with a predetermined degree of vacuum, a cooling gas supply device that supplies a cooling gas to the heat insulation chamber R, It also has some auxiliary equipment such as a control panel that controls the movement of each part. Moreover, the said to-be-processed object X is heat-processed in order to change a mechanical characteristic, and is generally various metal components.

  The casing 1 is a substantially cylindrical container as shown in the figure, and is installed on the floor in a horizontal posture such that the central axis L faces the horizontal direction. The door 2 is a curved disk type opening / closing door provided on one end side of the casing 1. That is, the door 2 closes or releases the circular opening of the casing 1 by connecting a part of a circular periphery facing the circular opening of the casing 1 to the casing 1 by a hinge (not shown). The clamp ring 3 is a holding part that holds the door 2 in a closed state, and presses the circular peripheral edge of the door 2 in close contact with the circular opening of the housing 1.

  The four legs 4 are spaced apart from the outer periphery and lower part of the housing 1 with a predetermined distance, and support the housing 1 in a state of being placed horizontally with respect to the floor. The mounting table 5 is a pair of pedestals facing each other in the horizontal direction at a predetermined distance in the lower part of the housing 1 as shown in the drawing, and is a horizontal direction perpendicular to the facing direction, that is, the direction of the central axis L (front-rear direction). It extends in a strip shape.

  The wheel 6 is provided at the rectangular bottom of the heat insulator 7 so as to correspond to the mounting table 5 described above, and supports the heat insulator 7 movably with respect to the mounting table 5. That is, the wheel 6 is provided with a total of two pairs spaced apart from each other in the direction of the central axis L on the rectangular bottom of the heat insulator 7, and one pair is at a position corresponding to one of the mounting table 5. The other pair is provided at a position corresponding to the other of the mounting table 5.

  The heat insulator 7 has a substantially box shape including six wall portions, and is formed of a predetermined heat insulating material. The heat insulating body 7 includes a heat insulating main body 7a, a door heat insulating body 7b, an upper open / close heat insulating body 7c, and a lower open / close heat insulating body 7d. A substantially box shape is formed by engaging the body 7d. Such a heat insulator 7 forms a heat insulating chamber R. That is, the internal space of the heat insulator 7 is a heat insulating chamber R.

  The heat insulating body 7 a is a combination of a plurality of heat insulating plates 7 e in a box shape, and is the main part of the heat insulating body 7. As shown in FIG. 2, the heat insulating body 7 a has the left wall portion, the right wall portion and the back wall portion of the heat insulating body 7 as a whole, as well as the upper wall portion and the lower portion of the heat insulating body 7 when viewed from the door 2 side. A part of the wall portion and the front wall portion (outer peripheral portion) are formed. That is, the heat insulating main body 7a has openings of a predetermined size at the central portions of the upper wall portion, the lower wall portion, and the front wall portion.

  The heat insulating plate 7e is a heat insulating component having a flat plate shape and a hollow structure, and includes a flat rectangular space K (space) as shown in FIG. That is, the heat insulating plate 7e forms a rectangular space K slightly smaller than the outer shape (rectangle) of the plate main body H inside the plate main body H made of a rectangular heat insulating material, and is positioned on the same diagonal line in the plate main body H. A pair of intake and exhaust ports P communicating with the rectangular space K are provided at a pair of corners.

  The heat insulating body 7a made of such a heat insulating plate 7e accommodates the workpiece X so as to be surrounded by a rectangular space K divided into a plurality of parts. That is, the heat insulation main body 7a in the present embodiment is configured by combining a plurality of heat insulation plates 7e in a box shape. Therefore, a plurality of rectangular spaces K are provided so as to surround the workpiece X in a divided manner.

  The rectangular space K is provided with four reinforcing members N that reinforce the mechanical strength of the heat insulating plate 7e without dividing the rectangular space K into a plurality of pieces. Each reinforcing member N is a member for reinforcing the mechanical strength of each heat insulating plate 7e against an external force (external pressure) acting on each heat insulating plate 7e by filling the heat insulating chamber R with a cooling gas. As shown in FIG. 3, each such reinforcing member N is parallel to one parallel surface h1, h1 in the rectangular space K and is spaced apart from the other by one end being orthogonal to the one parallel surface h1, h1. The parallel surfaces h2 and h2 are arranged so as to alternately contact one and the other.

  By such four reinforcing members N, a bent channel (gas channel) connecting the pair of intake and exhaust ports P is formed in the rectangular space K. Further, since the four guide members N are spaced from each other in the rectangular space K, the mechanical strength of the heat insulating plate 7e is improved. Each reinforcing member N also functions as a guide member that guides the flow of the inert gas G along the gas flow path. That is, the four guide members N reinforce the mechanical strength of the heat insulating plate 7e while satisfying that the inert gas G (fluid) is filled in substantially the entire rectangular space K.

  The intake / exhaust port P is connected to the intake / exhaust port P of the adjacent heat insulating plate 7e or the gas setting device 15 by a pipe (not shown). In FIG. 3, two pairs, that is, two intake / exhaust ports P are provided, but one intake / exhaust port P may be provided. That is, the intake / exhaust ports P of adjacent heat insulating plates 7e are connected to each other, and the intake / exhaust ports of one heat insulating plate 7e are connected to the gas setting device 15. Accordingly, one of the plurality of heat insulating plates 7e is directly connected to the gas setting device 15, and the other is indirectly connected to the gas setting device 15 via another heat insulating plate 7e.

  The door heat insulator 7 b constitutes the remaining portion (central portion) of the front wall portion of the heat insulator 7 and is fixed to the door 2. The door insulator 7b closes the opening of the front wall portion of the heat insulating body 7a when the door 2 is closed. The upper opening / closing heat insulating body 7 c constitutes the remaining portion (central portion) of the upper wall portion of the heat insulating body 7, and is fixed to the rod front end portion of the upper cylinder 13. The upper open / close heat insulating body 7c closes the opening of the upper wall portion of the heat insulating main body 7a when the upper cylinder 13 is operated. The lower opening / closing heat insulating body 7d constitutes the remaining portion (center portion) of the lower wall portion of the heat insulating body 7, and is fixed to the rod tip of the lower cylinder 14. The lower opening / closing heat insulating body 7d closes the opening of the lower wall portion of the heat insulating main body 7a when the lower cylinder 14 is operated.

  The hearth 8 is a pedestal on which the workpiece X is placed, and is supported on a part (outer peripheral portion) of the lower wall portion of the door heat insulator 7b as shown in FIG. A plurality of rollers are provided on the top of the hearth 8 in order to enable the workpiece X to move in the front-rear direction. The heating element 9 is an electric heater that generates heat when energized from the outside, and is provided in the vicinity of the heat insulating body 7 in the inner space of the heat insulating body 7, that is, in the heat insulating chamber R. That is, the heating element 9 is disposed so as to surround the workpiece X accommodated in the heat insulating chamber R, and uniformly heats the workpiece X from the surroundings.

  The cooling fan 10 is provided in the housing 1 above the heating element 9, that is, above the upper open / close heat insulator 7c, and is a drive source for convection of the cooling gas. That is, the cooling fan 10 is a centrifugal fan that rotates about a vertical direction as a rotation axis, and generates convection in the vertical direction in the housing 1 by sucking the cooling gas from the center and exhausting it in the peripheral direction. The fan motor 11 is a power source that rotationally drives such a cooling fan 10, and the drive shaft is fixed to the rotation shaft of the cooling fan 10.

  The cooling coil 12 is a kind of heat exchanger that cools the cooling gas by heat exchange. As shown in the drawing, the cooling coil 12 is provided on the upper side of the heat insulator 7 in the housing 1, that is, at a position in the middle of the convection of the cooling gas. Yes. More specifically, the cooling coil 12 is a heat transfer tube wound around the upper side of the heat insulator 7 with the drive shaft of the cooling fan 10, that is, the fan motor 11 being wound around, and a cooling liquid such as water inside. Circulate.

  The upper cylinder 13 is a hydraulic cylinder or an air cylinder fixed to the housing 1 with the cylinder shaft set in the horizontal direction, and an upper opening / closing heat insulator 7c is provided at the tip of a rod that advances / retreats in the direction of the cylinder shaft. It is fixed. The upper cylinder 13 moves the rod forward to close the opening of the upper wall portion of the heat insulating body 7a with the upper opening and closing heat insulating body 7c, and moves the rod backward to move the upper opening and closing heat insulating body 7c to the upper wall portion of the heat insulating main body 7a. Separate from the opening.

  The lower cylinder 14 is a hydraulic cylinder or an air cylinder fixed to the housing 1 with the cylinder axis set in the vertical direction, and a lower opening / closing insulator 7d is provided at the tip of a rod that advances / retreats in the direction of the cylinder axis. It is fixed. The lower cylinder 14 moves the rod forward to close the opening of the lower wall portion of the heat insulating body 7a with the lower opening and closing heat insulating body 7d, and moves the rod backward to retract the lower opening and closing heat insulating body 7d to the lower wall portion of the heat insulating main body 7a. Separate from the opening.

  The gas setting device 15 includes a gas tank that stores an inert gas G having a certain capacity, and is a device that variably sets the filling state of the inert gas G in the rectangular space K of each heat insulating plate 7e described above. That is, the gas setting device 15 is connected to the rectangular spaces K of all the heat insulating plates 7e constituting the heat insulating main body 7a, and the inert gas G is supplied to all the rectangular spaces K to thereby gas the rectangular spaces K. The filled state is set, or the inert gas G is recovered from all the rectangular spaces K, and the rectangular spaces K are set in a vacuum state.

  The inert gas G may be any gas that is chemically stable at the atmospheric temperature (up to about 1000 to 1200 ° C.) at the time of cooling the workpiece X in the heat insulating chamber R, for example, relatively inexpensive nitrogen. Gas.

  Next, the operation of the heat treatment apparatus configured as described above will be described in detail along the flowchart shown in FIG.

  For example, when performing the quenching process which is one form of heat processing to the to-be-processed object X using this heat processing apparatus, the to-be-processed object X is accommodated in the heat insulation chamber R by opening and closing the door 2 (step S1). . That is, the heat insulation chamber R is in a state in which the object to be processed X can be accommodated when the door 2 is released, and is in a state (isolation state) where the object X is blocked from the outside by closing the door 2. Accommodate.

  When the vacuum pump starts operating in this state, the heat insulation chamber R is evacuated, and a vacuum state with a predetermined degree of vacuum is obtained (step S2). Then, when the gas setting device 15 is activated, the inert gas G is recovered from each rectangular space K of the heat insulating main body 7a (step S3), so that each rectangular space K is in a vacuum state with a predetermined degree of vacuum. The degree of vacuum in the heat insulating chamber R and the degree of vacuum in each rectangular space K of the heat insulating main body 7a are substantially equal.

  Here, when the rectangular space K of each heat insulating plate 7e is set to a predetermined degree of vacuum by the gas setting device 15, each heat insulating plate 7e has a relatively low heat transfer coefficient. That is, at this time, that is, in the previous stage of the heat treatment of the workpiece X, the heat insulating body 7a composed of the plurality of heat insulating plates 7e is set to the state with the lowest heat transfer coefficient, that is, the state with the highest heat insulating performance.

  And the final preparation (heating preparation) with respect to the heat processing of the to-be-processed object X is performed (step S4). That is, in this heating preparation, the upper cylinder 13 operates to close the opening of the upper wall portion of the heat insulating main body 7a with the upper open / close heat insulating body 7c, and the lower cylinder 14 operates to lower the heat of the heat insulating main body 7a with the lower open / close heat insulating body 7d. Close the opening in the lower wall. With this heating preparation, the workpiece X is completely surrounded by the heat insulator 7.

  In this state, energization of the heating element 9 is started (step S5), and the heat treatment of the workpiece X by the heating element 9 is started. Then, by continuing energization to the heating element 9 for a predetermined time, the workpiece X is heated to a predetermined quenching temperature and held at the quenching temperature for a certain time. Then, when the energization of the heating element 9 is completed (step S6), the heat treatment of the workpiece X is completed.

  When this heat treatment is completed, the cooling gas supply device (not shown) is operated to supply the cooling gas to the heat insulating chamber R (step S7). Then, when the gas setting device 15 is operated, the inert gas G is supplied to each rectangular space K of the heat insulating main body 7a (step S8), so that each rectangular space K is in a gas-filled state. As a result, each heat insulating plate 7e constituting the heat insulating main body 7a has a higher thermal conductivity than when each rectangular space K is in a vacuum state.

  Further, as preparation for cooling, the upper cylinder 13 is operated to separate the upper open / close heat insulating body 7c from the opening of the upper wall portion of the heat insulating main body 7a, and the lower cylinder 14 is operated to move the lower open / close heat insulating body 7d to the heat insulating main body 7a. Separate from the opening of the lower wall (step S9). By this cooling preparation, the opening of the upper wall portion in the heat insulating body 7a and the opening of the lower wall portion in the heat insulating body 7a are released.

  In this state, when the fan motor 11 operates, the cooling fan 10 starts rotating (step S10). As a result, convection of the cooling gas is generated in the heat insulating chamber R, and the workpiece X is effectively cooled. And if the to-be-processed object X is cooled over predetermined time, the action | operation of the fan motor 11 will stop and the cooling fan 10 will stop rotation (step S11). As a result, the cooling (gas cooling) of the workpiece X with the cooling gas is completed.

  In this embodiment, the gas setting device 15 collects the inert gas G from each rectangular space K during the heat treatment of the workpiece X, and the gas setting device 15 collects the rectangular space during the cooling treatment of the workpiece X. An inert gas G is supplied to K. Therefore, as shown in FIG. 5, the heat insulating plate 7e is in a vacuum state with high heat insulating performance during the heat treatment, and is in a gas-filled state with low heat insulating performance during the cooling processing. Therefore, according to this embodiment, it is possible to cool the to-be-processed object X in the heat insulation chamber R more efficiently than the prior art in which heat insulation performance is the same at the time of heat treatment and at the time of cooling treatment.

In addition, this invention is not limited to the said embodiment, For example, the following modifications can be considered.
(1) In the said embodiment, although the rectangular space K (space) was provided only in the heat insulation main body 7a, this invention is not limited to this. In addition to the heat insulation main body 7a, a space is provided in the door heat insulator 7b, the upper open / close heat insulator 7c, and the lower open / close heat insulator 7d to heat the heat insulation performance of the door heat insulator 7b, the upper open / close heat insulator 7c, and the 7 lower open / close heat insulator d. You may switch between the time of processing and the time of cooling processing.

(2) In the above embodiment, the gas setting device 15 is provided as the fluid setting device, but the present invention is not limited to this. Instead of the inert gas G that is a gas, a liquid setting device that collects and supplies liquid to each rectangular space K may be provided as a fluid setting device.

(3) In the above embodiment, the heat insulating plate 7e provided with the four reinforcing members N is used, but the present invention is not limited to this. Instead of the heat insulating plate 7e, a heat insulating plate 7f provided with a granular reinforcing material M as shown in FIG. 6 may be used. The granular reinforcing material M provided on the heat insulating plate 7f is, for example, a spherical heat insulating material, and the rectangular space K is densely filled to such an extent that the respective surfaces come into contact with each other. As a result, when the external pressure is applied to the heat insulating plate 7f by the cooling gas, the mechanical strength of the heat insulating plate 7f can be reinforced.

(4) In the above embodiment, the process of step S3 is performed after the process of step S2. This is because the time required to depressurize the heat insulating chamber R to a predetermined vacuum level and each rectangular space K to a predetermined vacuum level. This is because the former is longer than the time required for decompression. However, the process of step S2 and the process of step S3 may be interchanged as necessary.

(5) In the above embodiment, the process of step S8 is performed after the process of step S7. This is the time required to supply a predetermined amount of cooling gas to the heat insulation chamber R and a predetermined amount of each rectangular space K. This is because the former is longer than the time required to supply the inert gas G. However, the process of step S7 and the process of step S8 may be interchanged as necessary.

X Object to be treated R Heat insulation chamber L Center axis G Inert gas K Rectangular space H Plate body N Reinforcement member M Granular reinforcement 1 Housing 2 Door 3 Clamp ring 4 Leg 5 Mounting table 6 Wheel 7 Heat insulator 7a Heat insulation body 7b Door Heat insulator 7c Upper open / close heat insulator 7d Lower open / close heat insulator 7e, 7f Heat insulation plate 8 Hearth 9 Heating element 10 Cooling fan 11 Fan motor 12 Cooling coil 13 Upper cylinder 14 Lower cylinder 15 Gas setting device

Claims (5)

A heat treatment apparatus for heat treatment by heating and cooling an object to be treated contained in a heat insulation chamber,
Forming the heat insulation chamber, and a heat insulator having a hollow structure in which a space is formed;
A fluid setting device that variably sets the filling state of the fluid in the space;
A plurality of the spaces are provided so as to surround the object to be processed.   2. The heat treatment apparatus according to claim 1, wherein the fluid setting device collects a fluid from the space when the object to be processed is heated, and supplies the fluid to the space when the object to be cooled is cooled. .   The heat treatment apparatus according to claim 1, wherein a reinforcing member is provided in the space.   The heat treatment apparatus according to claim 3, wherein the reinforcing member is a granular heat insulating material.   The heat treatment apparatus according to claim 1, wherein a guide member that guides the flow of the fluid is provided in the space.

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