JP2010145046A - Vacuum heat treatment furnace and heat treatment object supporting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress unevenness in cooling a treatment object in cooling the heat treatment object placed in a treatment chamber. <P>SOLUTION: This vacuum heat treatment furnace 10 includes the treatment chamber 13, a supporting part and a rotating part 16. In the treatment chamber 13, the heat treatment object 11 is heated, and the heated treatment object 11 is cooled in a cooling gas 12. The supporting part is disposed in the treatment chamber 13 to support the heat treatment object 11 in a state that the longitudinal direction of the heat treatment object 11 is directed from the inlet of the cooling gas 12 to the treatment chamber 13 toward an outlet, and is composed of a supporting member 19, an annular member 20, and a mounting jig 21. The rotating part 16 abuts on the heat treatment object 11, and rotates the heat treatment object 11 through its rotation. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a gas-cooled vacuum heat treatment furnace and a heat treatment object support device for gas-cooling a heated heat treatment object with a cooling gas.

  A vacuum heat treatment furnace is used for quenching a heat treatment object such as a tool. In this vacuum heat treatment furnace, the object to be heat treated is heated for a predetermined time in a state where the inside of the furnace is evacuated, and then a rapid cooling process is performed by introducing a low-temperature cooling gas or putting the object to be heat treated into an oil tank. In a conventional vacuum heat treatment furnace, as a heating method, a treatment chamber composed of a heat insulating layer with a heating element disposed on the inner surface side of the furnace is provided in the main body of the vacuum heat treatment furnace, and the heat treatment object as a heat treatment material is directly heated. There are an internal heat type that performs heat treatment and an external heat type that indirectly heats an object to be heat-treated by providing a heat source outside the processing chamber disposed in the main body. In addition, for example, a long member such as a broach is used as the heat treatment object, and in order to suppress the occurrence of bending of these heat treatment objects, a plurality of heat treatment objects are suspended in the processing chamber and quenched. Yes. And when cooling the heat processing target object after a heating, it is made to cool using the refrigerant gas introduced into the processing chamber from the outside (for example, patent documents 1-patent documents 3).

Japanese Patent No. 2656839 JP 07-229683 A JP 2002-333277 A

  By the way, in general, in a vacuum heat treatment furnace, heating and cooling are performed in the same place, and there are a heater and a furnace body for heating that surround the object to be heat treated. Most of the gas flows in the central part of a circle in which the heat treatment object is arranged concentrically. As a result, the flow velocity of the cooling gas is maximized, and the portion having the highest cooling effect is the central portion of a circle in which the heat treatment objects are arranged concentrically. For this reason, in the vacuum heat treatment furnace, the cooling gas flowing inside the annular group formed by the plurality of heat treatment objects arranged concentrically and the cooling gas flowing between the heat treatment object and the processing chamber are uniformly flowed. Therefore, it cannot be supplied to each heat treatment object.

  As a result, there is a difference in the cooling effect between the cooling gas flowing inside the plurality of heat treatment objects and the cooling gas flowing between the heat treatment object and the processing chamber, and cooling of the heat treatment object, in particular, the heat treatment object There is a problem that the cooling in the circumferential direction of the object becomes uneven. It is an object of the present invention to suppress non-uniform cooling of the heat treatment object when cooling the heat treatment object installed in the processing chamber.

  In order to solve the above-described problems and achieve the object, a vacuum heat treatment furnace according to the present invention includes a treatment chamber for heating a heat treatment object, and gas-cooling the heated heat treatment object with a cooling gas, and the treatment chamber. A support part that supports the heat treatment object so that a longitudinal direction of the heat treatment object is directed from an inlet of the cooling gas to an outlet of the treatment chamber; and the heat treatment object supported by the support part. And a rotating part that rotates the object.

  The apparatus for supporting a heat treatment object according to the present invention is provided in a vacuum heat treatment furnace having a treatment chamber for heating the heat treatment object and gas-cooling the heated heat treatment object with a cooling gas. A support part that is provided in the processing chamber and supports the heat treatment target so that a longitudinal direction of the heat treatment target is directed from an inlet of the cooling gas to the outlet to the processing chamber; And a rotating part that rotates the heat treatment object supported by the supporting part.

  In this way, when the heated heat treatment object is cooled with the cooling gas, the heat treatment object rotates, so that the heat treatment object includes a portion cooled by the cooling gas flowing in the center of the processing chamber, The portion cooled by the cooling gas flowing on the outer peripheral side is replaced with the passage of time. As a result, there is a difference in the heat transfer characteristics between the heat treatment object and the cooling gas due to the speed difference between the cooling gas flowing in the center of the processing chamber and the cooling gas flowing in the outer periphery of the processing chamber. However, since the difference in the heat transfer characteristics is averaged during cooling, non-uniform cooling of the heat treatment object is suppressed.

  As a preferred aspect of the present invention, in the vacuum heat treatment furnace, the rotating part is a member having a circular cross section, and the heat treatment object is brought into contact with an outer peripheral part and passes through the center of the cross section of the rotating part. It is desirable to rotate around the rotation axis. Further, as a preferred aspect of the present invention, in the heat treatment object support device, the rotating part is a member having a circular cross section, and the heat treatment object is brought into contact with an outer peripheral part, and the cross section of the rotating part is It is desirable to rotate using an axis passing through the center as a rotation axis. In this way, the heat treatment object can be rotated with a simple configuration.

  As a preferred aspect of the present invention, in the vacuum heat treatment furnace, it is desirable to have an outer holding portion that is disposed on an outer peripheral portion of the rotating portion and holds the heat treatment object together with the rotating portion. Moreover, as a preferable aspect of the present invention, in the heat treatment object support device, it is preferable that the heat treatment object support device includes an outer holding part that is disposed on an outer peripheral part of the rotation part and sandwiches the heat treatment object together with the rotation part. Thereby, since the movement of the rotation center of the heat treatment object is suppressed, the heat treatment object can be stably rotated, and uneven cooling of the heat treatment object can be more effectively suppressed.

  As a preferred aspect of the present invention, in the vacuum heat treatment furnace, the support portion grips at least one end of the heat treatment object and is suspended in the processing chamber, and the rotating portion is the support portion. It is desirable to rotate. Further, as a preferred aspect of the present invention, in the heat treatment object support device, the support part holds at least one end of the heat treatment object and suspends the heat treatment object inside the processing chamber, and the rotating part is It is desirable to rotate the support part. Thereby, even when the size of the heat treatment object is large, the heat treatment object can be rotated in the processing chamber.

  As a preferred aspect of the present invention, in the vacuum heat treatment furnace, it is desirable that a protrusion is provided at a position corresponding to the heat treatment object provided on the inner wall of the treatment chamber. As a result, the temperature boundary layer formed on the surface of the heat treatment object can be thinned, so that the temperature distribution in the longitudinal direction of the heat treatment object can be reduced.

  The present invention can suppress non-uniform cooling of the processing object when cooling the heat processing object installed in the processing chamber.

  Hereinafter, the present invention will be described in detail with reference to the drawings. The present invention is not limited to the following description. In addition, constituent elements in the following description include those that can be easily assumed by those skilled in the art, those that are substantially the same, and those in a so-called equivalent range.

[Embodiment 1]
In this embodiment, the longitudinal direction of the heat treatment object is directed from the inlet of the cooling gas provided in the treatment chamber to the outlet in the treatment chamber in which the heat treatment object is heated and the heated heat treatment object is gas-cooled with the cooling gas. When the heat treatment object heated by the cooling gas is cooled, the support part for supporting the heat treatment object and the rotating part for rotating the heat treatment object are provided. It is characterized in that it is rotated to the center. Hereinafter, an example in which the cooling gas flows in a direction parallel to the vertical direction, more specifically, in the vertical direction will be described, but the direction in which the cooling gas flows is not limited thereto. For example, the cooling gas may flow in the direction opposite to the vertical direction, or the cooling gas may flow in the horizontal direction.

  FIG. 1 is an overall configuration diagram showing the configuration of the vacuum heat treatment furnace according to the first embodiment. FIG. 2 is a cross-sectional view taken along the line AA of FIG. 3 is a BB arrow view of FIG. FIG. 4 is a timing chart showing an example of heat treatment by a vacuum heat treatment furnace. The gas-cooled vacuum heat treatment furnace 10 using a cooling gas is colored after being heated because the moisture in the furnace and the object to be heat treated is gasified and then decompressed again to refill the inert gas. Heat treatment (“bright heat treatment”), there are various advantages such as no decarburization, less deformation, and good working environment.

  As shown in FIG. 1, the vacuum heat treatment furnace 10 includes a processing chamber 13 that heats a heat treatment object 11 and gas-cools the heated heat treatment object 11 with a cooling gas 12. In the present embodiment, the heat treatment object 11 is, for example, a kind of broach of a cutting tool. In the present embodiment, the heat treatment object 11 is not limited to the broach. The vacuum heat treatment furnace 10 supports the gas supply unit 14 that supplies the cooling gas 12 to the processing chamber 13, the gas discharge unit 15 that discharges the cooling gas 12 from the processing chamber 13, and the heat treatment object 11 in the processing chamber 13. And a heat treatment object support device 40 having a rotating part 16 that rotates the support part and the heat treatment object 11. The gas supply unit 14 is provided on one end side of the processing chamber 13, and the gas discharge unit 15 is provided on the other end side of the processing chamber 13. The processing chamber 13 includes gas vents 17 and 18. The gas vent 17 allows the cooling gas 12 to pass from the gas supply unit 14 into the processing chamber 13, and the gas vent 18 is provided in the processing chamber 13. The cooling gas 12 is passed through the gas discharge unit 15.

  In the vacuum heat treatment furnace 10, the flow direction of the cooling gas 12 passing through the processing chamber 13 flows from the gas supply unit 14 to the gas discharge unit 15 of the vacuum heat treatment furnace 10. However, the flow direction of the cooling gas 12 may be the direction from the gas discharge unit 15 toward the gas supply unit 14. In this case, the cooling gas 12 is supplied from the gas discharge unit 15, and the cooling gas 12 in the processing chamber 13 is discharged to the gas supply unit 14. Further, the flow direction of the cooling gas 12 in the processing chamber 13 may be switched alternately. In this way, the cooling characteristics of the heat treatment object 11 can be made uniform in the longitudinal direction of the heat treatment object 11.

  The processing chamber 13 is formed by a heat insulating wall in the main body of the vacuum heat treatment furnace 10. The processing chamber 13 is a steel pressure vessel having a cylindrical body and is communicated with a vacuum pump. The heat insulating wall has a cylindrical shape made of a heat insulating material such as glass fiber, and is disposed in the main body of the vacuum heat treatment furnace 10 with a gap therebetween. A heater is provided on the inner peripheral surface of the heat processing wall 13. Is formed. The heat treatment object 11 is accommodated inside the processing chamber 13.

  In addition, the process chamber 13 is good also as a multilayered structure where a cylindrical heat insulation layer comprises two or more layers. Further, the partition wall 13a on the gas supply unit 14 side and the partition wall 13b on the gas discharge unit 15 side of the processing chamber 13 are formed of an annular heat insulating layer, and are provided in both the partition walls 13a and 13b made of the annular heat insulating layer. The inner holes formed form the gas vents 17 and 18 for the cooling gas 12, respectively. Further, the annular heat insulating layer is configured to be freely attached and detached from a cylindrical heat insulating layer constituting the side surface of the processing chamber 13. The heater provided on the inner peripheral surface of the processing chamber 13 is made of, for example, a bar-shaped graphite felt or the like, and is aligned in the vertical direction at a predetermined interval and arranged in the circumferential direction. The heater is connected to energization and input control means provided outside the processing chamber 13.

  After the inside of the processing chamber 13 is evacuated by a vacuum pump provided in the vacuum heat treatment furnace 10, the heat treatment object 11 is heated in a vacuum by a heater provided on the inner peripheral surface of the processing chamber 13. . When the heated heat treatment object 11 is cooled, the cooling gas 12 is supplied from the gas supply unit 14. The cooling gas 12 supplied to the gas supply unit 14 passes through the gas vents 17 provided in the partition wall 13a of the processing chamber 13, reaches a plurality of heat treatment objects 11 arranged in the processing chamber 13, and these are Cooling. As the cooling gas 12, for example, an inert gas such as argon, helium, nitrogen, or hydrogen is used. Further, in the main body of the vacuum heat treatment furnace 10, for example, a gas supply means (for example, a gas cylinder) and a fan are provided. The inert gas supplied from the gas supply means is cooled by a gas cooling device such as a cooler, and then supplied to the gas supply unit 14 as the cooling gas 12 by the rotation of the fan.

  A rectifying cylinder 22 is provided on the gas supply port 14 side of the gas vent 17 of the partition wall 13a. The rectifying cylinder 22 is configured in multiple layers by concentrically arranging cylindrical tubes 22a, 22b, 22c, and 22d having different inner and outer diameters. Thereby, the flow of the cooling gas 12 supplied into the processing chamber 13 can be rectified so that the cooling gas 12 flows near the center in the processing chamber 13, so that the cooling gas can be uniformly applied to the heat treatment object 11. 12 can be sent. The plurality of heat treatment objects 11 in the processing chamber 13 need to supply the cooling gas 12 uniformly to all of the heat treatment objects 11 when performing gas cooling. Although the objects 11 are arranged concentrically and at equal intervals, the arrangement of the heat treatment object 11 is not limited to this. Here, an example of heat treatment by the vacuum heat treatment furnace 10 will be described.

  When the heat treatment object 11 is disposed in the processing chamber 13, the heater is turned on at time t = t1 to start heating the vacuum heat treatment furnace 10. Then, when the temperature T in the processing chamber 13 reaches a predetermined heat treatment temperature Th (time t = t2), the electric power supplied to the heater is adjusted, and the temperature T in the processing chamber 13 is kept at the predetermined heat treatment temperature Th. Hold time (t3-t2). When time t = t3, the heater is turned off and the cooling gas 12 is supplied into the processing chamber 13 to rapidly cool the heat treatment object 11. When the temperature T in the processing chamber 13 reaches Tl (time t = t4), power is again applied to the heater, and the temperature T = Tl is maintained for a predetermined time (t5-t4). When time t = t5, the heater is turned off and the heat treatment object 11 is gradually cooled.

  As shown in FIG. 2, six heat treatment objects 11 are arranged in the outer peripheral portion of the rotating portion 16 in the processing chamber 13. Thus, in this embodiment, the six heat processing objects 11 are concentrically arranged in the processing chamber 13 to form an annular group. In the present embodiment, six heat treatment objects 11 are arranged in the processing chamber 13, but the present invention is not limited to this. As shown in FIGS. 1 and 3, a support member 19 for arranging the heat treatment object 11 in the processing chamber 13 is provided in the processing chamber 13. An annular member 20 is attached to the support member 19, and a plurality of heat treatment objects 11 are suspended from the annular member 20 by a plurality of attachment jigs 21 provided on the annular member 20. Placed inside. In this embodiment, the support part which comprises the heat processing target object support apparatus 40 is comprised with the supporting member 19, the annular member 20, and the attachment jig 21. As shown in FIG. With such a configuration, the support portion has the heat treatment object 11 so that the longitudinal direction of the heat treatment object 11 is directed from the inlet (gas vent 17) of the cooling gas 12 to the processing chamber 13 toward the outlet (gas vent 18). 11 is supported.

  In this embodiment, the rotation part 16 which comprises the heat processing target object support apparatus 40 is a member with a circular cross section. In the present embodiment, as shown in FIGS. 2 and 3, the rotating portion 16 is a columnar member. The rotating part 16 makes its outer peripheral part contact the outer peripheral part of the heat treatment object 11 arranged in the processing chamber 13 by the support part. The rotating unit 16 rotates about the axis Z passing through the center (more specifically, the center of gravity) of its cross section as a rotation axis. Thus, the axis Z of the rotation unit 16 becomes the rotation axis of the rotation unit 16.

  The rotating part 16 is rotatably supported by a rotating part support 16B having a bearing. Further, the rotating part support 16 </ b> B is rotatably supported by the rotating part support member 23 in the processing chamber 13. With such a configuration, the rotating unit 16 is rotatably supported in the processing chamber 13. The rotating unit 16 is driven by an electric motor 32 which is a rotating unit driving unit. In the present embodiment, the power generated by the electric motor 32 passes through the speed reducer 31 and is transmitted to the rotating unit 16 through the power transmission shaft 30 connected to the rotating unit 16. Thereby, the electric motor 32 rotates the rotating unit 16. In the present embodiment, the electric motor and the speed reducer 31 are disposed in the gas discharge unit 15, but the electric motor 32 and the speed reducer 31 may be disposed outside the gas discharge unit 15.

  Since the heat treatment object 11 is in contact with the outer peripheral portion of the rotating part 16, when the rotating part 16 rotates (in the direction of arrow R in FIG. 3), the heat treatment object is caused by friction between the rotating part 16 and the heat treatment object 11. The object 11 also rotates. In the cooling step after heating the heat treatment object 11, if the rotating unit 16 is rotated by the electric motor 32 while supplying the cooling gas 12 into the processing chamber 13, the heat treatment object 11 is also rotated. Thus, since the heat treatment object 11 rotates, the heat treatment object 11 flows through the portion cooled by the cooling gas 12 flowing in the center side of the processing chamber 13 and the outer peripheral side (inner wall 13w side) of the processing chamber 13. The portion cooled by the cooling gas 12 is replaced. As a result, even when there is a difference in heat transfer characteristics due to the speed difference between the cooling gas 12 flowing in the center side of the processing chamber 13 and the cooling gas 12 flowing in the outer peripheral side of the processing chamber 13, Since the difference in heat transfer characteristics with the gas 12 is averaged and uneven cooling of the heat treatment object 11 is suppressed, the temperature distribution in the circumferential direction of the heat treatment object 11 is reduced. As a result, the heat treatment object support device 40 and the vacuum heat treatment furnace 10 including the same can reduce the overall distortion, hardness variation, internal structure and crystal grain size variation of the heat treatment object 11.

  Moreover, in this embodiment, the rotation part 16 is arrange | positioned concentrically within the process chamber 13, and is arrange | positioned in the center part of the six heat processing target objects 11 which form the cyclic | annular group. With such a configuration, the cooling gas 12 supplied from the gas supply unit 14 into the processing chamber 13 via the gas vent 17 of the partition wall 13a collides with the gas supply unit 14 side of the rotating unit 16 and the vicinity thereof. Then, the flowing direction of the cooling gas 12 is changed, and the cooling gas 12 flows in a distributed manner on the center side of the processing chamber 13 and the outer peripheral side of the processing chamber 13. As a result, the flow rate of the cooling gas 12 flowing in the center of the processing chamber 13 is reduced to reduce the flow velocity, and the flow rate of the cooling gas 12 flowing in the outer peripheral side of the processing chamber 13 is increased to increase the flow velocity.

  Thereby, the velocity distribution of the cooling gas 12 flowing in the center side of the processing chamber 13 and the cooling gas 12 flowing in the outer peripheral side of the processing chamber 13 can be made uniform. As a result, the difference between the heat transfer characteristics of the cooling gas 12 flowing in the center of the processing chamber 13 and the heat transfer characteristics of the cooling gas 12 flowing in the outer peripheral side of the processing chamber 13 can be reduced. The difference in the cooling effect can be reduced more effectively. As a result, since the heat treatment object 11 can be cooled more uniformly, the temperature distribution in the circumferential direction of the heat treatment object 11 can be further reduced. And the distortion of the whole heat processing target object 11, the dispersion | variation in hardness, the internal structure, and the dispersion | variation in crystal grain size can be reduced more effectively.

  The gas vents 17, 18 of the partition walls 13 a, 13 b are arranged so as to face the processing chamber 13, and contact with the heat treatment object 11, and the cooling gas 12 whose temperature has been increased is supplied to the other side of the processing chamber 13. The gas passes through the gas vent 18 provided in the partition wall 13 b and is discharged from the gas discharge unit 15 to the outside of the processing chamber 13. In the vacuum heat treatment furnace 10, the gas vent 18 of the partition wall 13 b is also provided with a rectifying cylinder 22, and the flow of the cooling gas 12 discharged from the processing chamber 13 is rectified and then discharged to the gas discharge unit 15. ing. The cooling gas 12 flowing out from the gas vent 18 of the partition wall 13b to the gas discharge unit 15 is cooled again by the gas cooling device described above, and then supplied to the gas supply unit 14 by a fan and supplied into the processing chamber 13. The

[First Modification]
FIG. 5 is a cross-sectional view illustrating a vacuum heat treatment furnace according to a first modification of the first embodiment. FIG. 6 is a diagram illustrating a part of the vacuum heat treatment furnace according to the first modification of the first embodiment. In this modification, in addition to the configuration of the first embodiment, a protrusion 25 is provided on the inner wall 13w of the processing chamber 13 at a position corresponding to the heat treatment object 11. As shown in FIGS. 5 and 6, in this modification, the vacuum heat treatment furnace 10 c is formed with protrusions 25 on the inner wall 13 w of the treatment chamber 13 at positions corresponding to the heat treatment object 11.

  As shown in FIG. 6, the cooling gas 12 supplied into the processing chamber 13 is heated from the end portion 11 t 1 of the heat treatment object 11 with which the cooling gas 12 collides with the high temperature portion of the heat treatment object 11 and the processing chamber 13. A temperature boundary layer 26 is formed between the low temperature portion of the cooling gas 12 supplied therein. Further, when the heat treatment object 11 is cooled, the cooling gas 12 passing through the processing chamber 13 flows in one direction, so that the temperature boundary layer 26 becomes thicker as it goes downstream in the flow direction of the cooling gas 12.

  As shown in FIG. 6, as shown in FIG. 6, the protrusions 25 are provided on the inner partition wall 13 c of the processing chamber 13 at positions corresponding to the heat treatment object 11, respectively. The thickness of the temperature boundary layer 26 can be reduced. As a result, the heat transfer rate to the heat treatment object 11 can be improved, so that the heat treatment object 11 can be more efficiently cooled by the cooling gas 12 supplied into the processing chamber 13.

[Second Modification]
FIG. 7 is a diagram illustrating a rotating unit according to a second modification of the first embodiment. In this modification, in addition to the configuration of the first embodiment, the tip portion 16bt of the rotating portion 16b on the upstream side in the flow direction of the cooling gas 12 is formed in a hemispherical shape. As shown in FIG. 7, in the present modification, the tip portion 16bt of the rotating portion 16b is hemispherical, so that the cooling gas 12 colliding with the tip portion 16bt of the rotating portion 16b can flow smoothly. As a result, the cooling gas 12 supplied to the processing chamber 13 can be supplied to the rotating portion as compared with the case where the upper end portion is configured in a planar shape like the rotating portion 16 of the vacuum heat treatment furnace 10 according to the first embodiment. It is possible to smoothly disperse the plurality of heat treatment objects 11 arranged around 16b.

[Third Modification]
FIG. 8 is an overall configuration diagram illustrating a configuration of a vacuum heat treatment furnace according to a third modification of the first embodiment. FIG. 9 is a view taken along arrow BB in FIG. In this modification, in addition to the configuration of the first embodiment, an outer holding portion 20ar that sandwiches the heat treatment object 11 together with the rotating portion 16 is provided on the outer peripheral portion of the rotating portion 16. As shown in FIG. 9, the annular member 20a is provided with a plurality of supports 20at that support the outer holding portion 20ar protruding outward in the radial direction. The outer holding portion 20ar is a cylindrical member, and is supported by the support body 20at so as to be rotatable about the axis of the outer holding portion 20ar.

  The heat treatment object 11 arranged on the outer peripheral part of the rotating part 16 is arranged between the two outer holding parts 20 ar and the rotating part 16. As a result, the heat treatment object 11 is sandwiched between the outer holding portion 20ar and the rotating portion 16. At this time, the outer holding portion 20ar may apply a force toward the rotating portion 16 to the heat treatment object 11. Thereby, the heat treatment object 11 can be reliably held between the outer holding portion 20ar and the rotating portion 16. In the present modification, the position of the heat treatment object 11 can be regulated by the outer holding portion 20ar, and therefore, when the heat treatment object 11 is rotated by rotating the rotating unit 16, the movement of the rotation axis of the heat treatment object 11 is suppressed. it can. As a result, in cooling after heating, the heat treatment object 11 is stably rotated to more reliably suppress non-uniform cooling of the heat treatment object 11 and suppress the temperature distribution in the circumferential direction of the heat treatment object. it can.

[Embodiment 2]
FIG. 10 is an overall configuration diagram showing the configuration of the vacuum heat treatment furnace according to the second embodiment. The second embodiment is substantially the same as the first embodiment except that the rotating part 16c directly rotates the support part 21c that holds at least one end of the heat treatment object 11 and suspends it in the processing chamber 13. Is different. Other configurations are the same as those of the first embodiment. As shown in FIG. 10, the vacuum heat treatment furnace 10c includes a heat treatment object support device 40c having a support portion 21c and a rotation portion 16c. The support portion 21c includes a gripping mechanism such as a chuck for gripping at least one end portion of the heat treatment object 11, and is attached to the rotating portion 16c.

  The rotating part 16c is connected to the power transmission shaft 30a. The end of the power transmission shaft 30a on the side opposite to the rotating portion 16c is connected to the speed reducer 31a. With such a configuration, the power generated by the electric motor 32a is transmitted to the rotating part 16c via the speed reducer 31a and the power transmission shaft 30a, and rotates the rotating part 16c. When the rotation part 16c rotates, the support part 21c attached to this also rotates. In the present embodiment, the speed reducer 31 a and the electric motor 32 a are disposed in the gas supply unit 14.

  At the time of cooling, the electric motor 32a rotates and rotates the rotation part 16c and the support part 21c. As a result, the difference in heat transfer characteristics between the heat treatment object 11 and the cooling gas 12 is averaged and uneven cooling of the heat treatment object 11 is suppressed, so that the temperature distribution in the circumferential direction of the heat treatment object 11 is suppressed. Is reduced. As a result, the heat treatment object support device 40c and the vacuum heat treatment furnace 10c including the same can reduce the overall distortion, hardness variation, internal structure and crystal grain size variation of the heat treatment object 11. The vacuum heat treatment furnace 10c and the heat treatment object support device 40c according to the present embodiment are preferable when the size of the heat treatment object 11 is large.

  As described above, the vacuum heat treatment furnace and the heat treatment object support device according to the present invention are useful for uniformly cooling the heat treatment object in the heat treatment by the vacuum heat treatment furnace.

1 is an overall configuration diagram showing a configuration of a vacuum heat treatment furnace according to Embodiment 1. FIG. It is AA sectional drawing of FIG. It is a BB arrow line view of FIG. It is a timing chart which shows an example of the heat processing by a vacuum heat processing furnace. It is sectional drawing which shows the vacuum heat processing furnace which concerns on the 1st modification of Embodiment 1. It is a figure which shows a part of vacuum heat treatment furnace which concerns on the 1st modification of Embodiment 1. FIG. It is a figure which shows the rotation part which concerns on the 2nd modification of Embodiment 1. FIG. It is a whole block diagram which shows the structure of the vacuum heat processing furnace which concerns on the 3rd modification of Embodiment 1. It is a BB arrow line view of FIG. FIG. 3 is an overall configuration diagram showing a configuration of a vacuum heat treatment furnace according to a second embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10, 10c Vacuum heat treatment furnace 11 Heat processing object 11t1 End part 12 Cooling gas 13 Processing chamber 13a, 13b Partition wall 13c Inner partition wall 13w Inner wall 14 Gas supply part 15 Gas discharge part 16, 16b, 16c Rotation part 16B Rotation part support body 16bt Tip Portions 17, 18 Gas vent 19 Support member 20, 20a Annular member 20ar Outer holding portion 20at Support body 21 Mounting jig 21c Support portion 22 Rectifier tube 22a, 22b, 22c Tube 23 Rotating portion support member 25 Projection portion 26 Temperature boundary layer 30, 30a Power transmission shaft 31, 31a Reduction gear 32, 32a Electric motor 40, 40c Heat treatment object support device

Claims (9)

A treatment chamber for heating the object to be heat-treated, and gas-cooling the heated object to be heat-treated with a cooling gas;
A support portion that is provided in the processing chamber and supports the heat treatment target so that a longitudinal direction of the heat treatment target is directed from an inlet of the cooling gas to the processing chamber toward an outlet;
A rotating unit for rotating the heat treatment object supported by the support unit;
A vacuum heat treatment furnace comprising:   2. The vacuum heat treatment according to claim 1, wherein the rotating part is a member having a circular cross section, and the heat treatment target is brought into contact with an outer peripheral part, and the rotating part rotates around an axis passing through the center of the cross section of the rotating part. Furnace.   The vacuum heat treatment furnace according to claim 2, further comprising an outer holding portion that is disposed on an outer peripheral portion of the rotating portion and sandwiches the heat treatment object together with the rotating portion. The support part holds at least one end of the object to be heat-treated and is suspended inside the processing chamber,
The vacuum heat treatment furnace according to claim 1, wherein the rotating unit rotates the support unit.   5. The vacuum heat treatment furnace according to claim 1, wherein the vacuum heat treatment furnace is provided on an inner wall of the treatment chamber and has a protrusion at a position corresponding to the heat treatment object. It is provided in a vacuum heat treatment furnace provided with a treatment chamber for heating a heat treatment object and gas-cooling the heated heat treatment object with a cooling gas, and supports the heat treatment object,
A support portion that is provided in the processing chamber and supports the heat treatment target so that a longitudinal direction of the heat treatment target is directed from an inlet of the cooling gas to the processing chamber toward an outlet;
A rotating unit for rotating the heat treatment object supported by the support unit;
An apparatus for supporting an object to be heat-treated, comprising:   7. The heat treatment target according to claim 6, wherein the rotating part is a member having a circular cross section, the heat treatment target is brought into contact with an outer peripheral part, and an axis passing through the center of the cross section of the rotating part is rotated as a rotation axis. Object support device.   The heat treatment object support device according to claim 7, further comprising an outer holding part that is disposed on an outer peripheral part of the rotation part and sandwiches the heat treatment object together with the rotation part. The support part holds at least one end of the object to be heat-treated and is suspended inside the processing chamber,
The heat treatment object support device according to claim 6, wherein the rotation unit rotates the support unit.

Images