JP2012229878A - Heat treatment device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat treatment device which can cool a bearing with a simple structure without requiring a separate device, and can reduce facility cost and operation cost.SOLUTION: The heat treatment device 1 includes a heat treatment furnace 2, a stirring blade 4, bearings 5, 6 and a rotating blade 7. The heat treatment furnace 2 houses a treated object. The stirring blade 4 is mounted on a tip end of a drive shaft 18 which passes through a furnace wall of the heat treatment furnace 2 and is arranged over an inside and outside of the heat treatment furnace 2, and stirs atmosphere gas in the furnace. The bearings 5, 6 are mounted outside the heat treatment furnace by using bearing holding members 14, 16, and axially support the drive shaft 18. The rotating blade 7 is fixed on the drive shaft 18. In this structure, the bearing holding members 14, 16 and the bearing 5, 6 are cooled by an air flow generated when the rotating blade 7 is rotated by the drive shaft 18.

Description

  The present invention relates to a heat treatment apparatus that accommodates an object to be processed such as a wafer in a heat treatment furnace and performs heat treatment.

  Conventionally, in a heat treatment apparatus that heats a workpiece such as a wafer in a heat treatment furnace, the atmosphere in the furnace is agitated by a stirring blade disposed in the furnace in order to make the temperature in the furnace uniform. (See Patent Documents 1 and 2.) The stirring blade is attached to the tip of the drive shaft that penetrates the heat treatment furnace. The drive shaft is supported by a bearing outside the heat treatment furnace.

  During the heat treatment, the temperature in the furnace reaches 900-1000 ° C. At this time, the heat in the furnace is transferred from the stirring blade disposed in the furnace to the bearing through the drive shaft. Since the bearing is a precision part, the usable temperature range is defined by the standard. Therefore, in order to stir the atmosphere in the furnace stably, it is necessary to cool the drive shaft and the bearing so that the temperature of the bearing does not exceed the upper limit of the usable temperature.

  Therefore, Patent Documents 1 and 2 disclose a water-cooled drive shaft or bearing cooling mechanism for circulating cooling water. Specifically, Patent Document 1 discloses that a water cooling jacket is constructed on a bearing holding member that holds a bearing, and Patent Document 2 discloses that a spiral water pipe is wound around a drive shaft. ing.

Japanese Utility Model Publication No. 2-118748 JP 2003-21472 A

  However, the above-described water-cooled cooling mechanism requires a cooling water circulation device separately from the heat treatment device, and also requires a water routing pipe, resulting in high equipment costs.

  Further, even after the operation of the heat treatment apparatus is stopped due to the suspension or inspection of the facilities, the bearing has heat due to the residual heat of the heat treatment furnace, so it is necessary to circulate the cooling water for a while. Since the cooling water circulation device and the control system of the heat treatment device are separate, a separate operation is required to stop the cooling water, and the operating cost is increased.

  The present invention has been made in view of the above-described problems, and does not require a separate device, can cool the bearing with a simple configuration, and can reduce facility costs and operation costs. An object is to provide an apparatus.

  The heat treatment apparatus of the present invention includes a heat treatment furnace, a stirring blade, a bearing, and a rotary blade. The heat treatment furnace accommodates an object to be processed. The stirring blade is attached to the tip of a drive shaft that passes through the furnace wall of the heat treatment furnace and is disposed between the inside and the outside of the heat treatment furnace, and stirs the atmospheric gas in the furnace. The bearing is attached to the outside of the heat treatment furnace using a bearing holding member, and supports the drive shaft. The rotor blade is fixed to the drive shaft. In this configuration, the bearing holding member and the bearing are cooled by an air flow generated by rotating the rotor blade by the drive shaft.

  According to this configuration, the drive shaft and the shaft holding member can be air-cooled. A cooling water circulation device is not required, and piping for water handling is also unnecessary.

  Moreover, the heat processing apparatus of this invention is provided with the duct which surrounds the said bearing holding member, the said bearing, and the said rotary blade. According to this structure, an air flow can be drawn in in a duct and a shaft holding member and a bearing can be cooled reliably.

  A heat radiating fin may be provided around the bearing holding member. According to this, since the heat of the bearing holding member and the bearing can be radiated through the radiating fin, the cooling efficiency is improved. In this case, when the heat radiating fin is brought into contact with the duct, the cooling efficiency is further improved.

  According to the present invention, it is possible to cool the bearing with a simple configuration without requiring a separate device. Thereby, reduction of an installation cost and an operating cost is attained.

It is a perspective sectional view showing the important section of the heat treatment apparatus concerning one embodiment of this invention. Fig.2 (a) is an enlarged view of the principal part of the said heat processing apparatus explaining the distribution direction of the airflow at the time of drive shaft right rotation. FIG. 2B is an enlarged view of the main part of the heat treatment apparatus for explaining the flow direction of the air flow when the drive shaft rotates counterclockwise.

  A heat treatment apparatus according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective sectional view showing a main part of a heat treatment apparatus according to one embodiment of the present invention.

  As shown in FIG. 1, the heat treatment apparatus 1 according to the present embodiment mainly includes a heat treatment furnace 2, a drive motor 3, a stirring blade 4, first and second bearings 5 and 6, and a rotating blade 7. In this figure, the heat treatment furnace 2 is not shown in its entirety, and only a part of the ceiling portion where the stirring blades 4 are arranged is shown.

  The heat treatment furnace 2 accommodates an object not shown. The object to be processed is not particularly limited, and examples thereof include a semiconductor wafer and a glass substrate of a liquid crystal panel. The material of the heat treatment furnace 2 is preferably a heat-resistant metal or alloy, for example, a sheet metal such as steel or stainless steel. Two layers of heat insulating materials 8 and 9 are arranged on the inner wall of the heat treatment furnace 2.

  A cylindrical outer cylinder 10 is fixed to the upper part of the heat treatment furnace 2. The outer cylinder 10 defines a flow path of an air flow generated in the direction of the drive shaft 18 with the rotation of the rotor blade 7 described later. The outer cylinder 10 passes through the ceiling wall of the heat treatment furnace 2 and is inserted into the upper portion of the heat insulating material 8. A motor support member 11 and a first bearing support member 12, which are ring-shaped disks, are fixed to the upper end and the lower end of the outer cylinder 10, respectively.

  The drive motor 3 is fixed on the motor support member 11. The motor shaft 3 </ b> A of the drive motor 3 is inserted into the axis of the outer cylinder 10. A cup-shaped second bearing support member 13 is mounted on the first bearing support member 12 using a flange 13A at the upper end. A first bearing holding member 14 is supported on the bottom surface of the second bearing support member 13. The first and second bearing support members 12 and 13 support the first bearing 5 via the first bearing holding member 14.

  The first bearing holding member 14 is a cylindrical body formed in a stepped shape having two upper and lower steps, and holds the first bearing 5 on the upper step portion thereof. The upper opening of the first bearing holding member 14 is covered with a cap 15 to protect the first bearing 5 inside. The material of the first bearing holding member 14 is preferably a metal having good thermal conductivity, such as copper or aluminum.

  A plurality of radiating fins 14 </ b> A are radially and integrally provided on the outer periphery of the first bearing holding member 14. In addition, when providing the radiation fin 14A, you may attach to the circumference | surroundings of the 1st bearing holding member 14 by adhesion | attachment, welding, etc. as a separate body. Although the number of the radiation fins 14A is not limited, for example, 6 to 36 is preferable. The material of the heat radiating fins 14A is preferably a metal having good thermal conductivity, such as copper or aluminum, for example, similar to the material of the first bearing holding member 14 described above.

  A second bearing holding member 16, which is a ring-shaped disk that bisects the space in the outer cylinder 10 in the vertical direction, is attached to the inner side of the outer cylinder 10. The second bearing 6 is held (supported) at the center of the second bearing holding member 16. In the periphery of the second bearing holding member 16, communication ports 16 </ b> A made up of a plurality of elongated holes are opened side by side in the circumferential direction. The upper and lower spaces in the outer cylinder 10 partitioned by the second bearing holding member 16 communicate with each other through these communication ports 16A.

  Two rectangular first vent holes 10A (only one is shown in FIG. 1) are opened in a window shape above the second bearing holding member 16 of the outer cylinder 10. Below the second bearing holding member 16 of the outer cylinder 10, two rectangular second vent holes 10 </ b> B (in FIG. 1, a cross section in which the front window frame is cut) are window-shaped. Is open. In the first and second vents 10A and 10B, the two vents are arranged facing each other in the 180 ° direction in the circumferential direction of the outer cylinder 10. Further, the relative position between the first vent 10 </ b> A and the second vent 10 </ b> B is shifted by approximately 90 ° in the circumferential direction of the outer cylinder 10. Thereby, it can suppress that an air flow shortcuts inside and outside of the outer cylinder 10, and it is preferable.

  Note that the number, shape (size), arrangement, and relative position between the first and second vent holes of the first and second vent holes 10A and 10B are not limited to the above.

  A drive shaft 18 is fixed to the motor shaft 3 </ b> A of the drive motor 3. The drive shaft 18 is supported by the first and second bearings 5 and 6. The drive shaft 18 rotates together with the motor shaft 3A when the drive motor 3 operates. The drive shaft 18 passes through the furnace wall of the heat treatment furnace 2 and the heat insulating materials 8 and 9 and is disposed across the inside and outside of the heat treatment furnace 2. A stirring blade 4 is attached to the tip of the drive shaft 18. The stirring blade 4 is rotated by the drive shaft 18 and stirs the atmospheric gas in the furnace.

  The rotary blade 7 has a configuration in which a plurality of plate-like blades 7B are integrally provided around a ring-shaped shaft portion 7A. The rotary blade 7 is fixed to the drive shaft 18 using the shaft portion 7A. The position of the rotary blade 7 in the axial direction is between the first and second bearings 5 and 6 and is directly above the cap 15 of the first bearing holding member 14 as shown in the figure. Thereby, the 1st bearing holding member 14, the 1st bearing 5, and the rotary blade 7 are concentrated in the axial direction, and are arrange | positioned compactly. A cylindrical duct 17 is provided so as to surround the first bearing holding member 14, the first bearing 5, and the rotary blade 7. The duct 17 concentrically divides the space below the second bearing holding member 16 in the outer cylinder 10 and has a function of reliably drawing an air flow around the first bearing holding member 14.

  Although the inclination with respect to the horizontal of the blade | wing 7B of the rotary blade 7 is not limited, For example, it is preferable to set it as 10-45 degrees. The number of blades 7B is not limited, but is preferably 4 to 10 for example. The gap from the tip of the blade 7B to the inner wall of the duct 17 is not limited, but is preferably 10 mm or less, for example. Although the diameter of the entire rotor blade 7 is not limited, for example, it is preferable to set the diameter of the drive shaft 18 to be twice or more.

  A plurality of mounting fins 17A are provided radially around the outer periphery of the duct 17 at intervals of 90 °, for example. The duct 17 is suspended on the flange 13A of the second bearing support member 13 using these mounting fins 17A. The lower end of the duct 17 is fixed in a state where it is lifted from the bottom surface of the cup-shaped second bearing support member 13. Thereby, the circulation of air through the lower end opening of the duct 17 is not hindered.

  The radiating fins 14 </ b> A are in contact with the inner peripheral surface of the duct 17 and the bottom surface of the second shaft support member 13. Thereby, the duct 17 and the 2nd bearing support member 13 can be heat-transferred, and the heat of the 1st bearing 5 can be radiated.

  Next, the operation of the heat treatment apparatus configured as described above will be described with reference to FIG. Fig.2 (a) is an enlarged view of the principal part of the said heat processing apparatus explaining the distribution direction of the airflow at the time of drive shaft right rotation. FIG. 2B is an enlarged view of the main part of the heat treatment apparatus for explaining the flow direction of the air flow when the drive shaft rotates counterclockwise.

  As shown in FIG. 2A, when the drive shaft 18 is rotated to the right (see the white arrow), the rotation of the rotor blades 7 causes the second ventilation port 10B to be an intake port and the first intake port 10A to be an exhaust port. Thus, an air flow in the direction of the drive shaft 18 is generated in the outer cylinder 10 (see black arrows). That is, as shown in the drawing, the air outside the outer cylinder 10 is sucked into the outer cylinder 10 from the second vent 10B, flows from the top to the bottom along the outer peripheral surface of the duct 17, and sinks to the lower side of the duct 17 as V Inverted and drawn from the lower end opening of the duct 17 and flows from the bottom to the top in the duct 17, exits from the upper end opening of the duct 17, and then flows further upward through the communication port 16 </ b> A of the second bearing holding member 16. The air is exhausted from the 1 vent 10 </ b> A to the outside of the outer cylinder 10.

  On the other hand, as shown in FIG. 2B, when the drive shaft 18 is rotated counterclockwise (see white arrows), the rotation of the rotor blades 7 causes the first air vent 10A to become the air intake and the second air intake 10B to move. An air flow in the direction of the drive shaft 18 is generated in the outer cylinder 10 so as to be an exhaust port (see a black arrow). That is, as shown in the figure, the air outside the outer cylinder 10 is sucked into the outer cylinder 10 from the first vent 10A, flows downward through the communication port 16A of the second bearing holding member 16, and is further drawn from the upper end opening of the duct 17. After flowing from the top to the bottom in the duct 17 and exiting from the lower end opening of the duct 17, the V is inverted at the lower side of the duct 17, and flows from the bottom to the top along the outer peripheral surface of the duct 17. The air is exhausted from the vent 10B to the outside of the outer cylinder 10.

  That is, although the direction of the airflow is reversed depending on whether the drive shaft 18 rotates clockwise or counterclockwise, the first and second bearing holding members 14 and 16 placed in the airflow passage are cooled by the airflow. Heat in the furnace is transferred to the bearings 5 and 16 through the drive shaft 18. That is, the heat from the bearings 5 and 6 is transferred to the bearing holding members 14 and 16. In other words, the bearings 5 and 6 can be indirectly cooled by cooling the bearing holding members 14 and 16 as described above. In particular, the first bearing 5 that is close to the heat treatment furnace 2 and is likely to reach a high temperature is effectively radiated through the radiation fins 14A of the first bearing holding member 14, so that it can be cooled efficiently. Become.

  According to the present embodiment, it is possible to cool the drive shaft and the shaft holding member. A cooling water circulation device is not required, and piping for water handling is also unnecessary. Therefore, it is possible to cool the bearing with a simple configuration without requiring a separate device. Thereby, reduction of an installation cost and an operating cost is attained.

  The present invention is applicable not only to carburizing furnaces typified by heat treatment furnaces, but also to all heating devices equipped with a heat treatment furnace that employs a configuration in which the atmosphere in the furnace is forcibly stirred by stirring blades. It is.

  The above description of the embodiment is to be considered in all respects as illustrative and not restrictive. The scope of the present invention is shown not by the above-described embodiments but by the claims. Furthermore, the scope of the present invention is intended to include all modifications within the meaning and scope equivalent to the claims.

1-heat treatment apparatus 2-heat treatment furnace 3-drive motor 4-stirring blade 5-first bearing 6-second bearing 7-rotary blade 10-outer cylinder 14-first bearing holding member 14A-radiating fin 16-second bearing Holding member 17-duct 18-drive shaft

Claims (5)

A heat treatment furnace for storing the object to be treated;
Agitating blades that are attached to the tip of a drive shaft that is disposed across the inside and outside of the heat treatment furnace through the furnace wall of the heat treatment furnace, and stir the atmospheric gas in the furnace
A bearing mounted outside the heat treatment furnace using a bearing holding member and bearing the drive shaft;
In a heat treatment apparatus having
A rotating blade fixed to the drive shaft;
The heat processing apparatus which cools the said bearing holding member and the said bearing with the airflow which arises when the said rotary blade is rotated with the said drive shaft.   The heat treatment apparatus according to claim 1, further comprising a duct surrounding the bearing holding member, the bearing, and the rotor blade.   The heat treatment apparatus according to claim 1, wherein a radiating fin is provided around the bearing holding member.   The heat treatment apparatus according to claim 2, wherein a radiating fin is provided around the bearing holding member, and the radiating fin is brought into contact with the duct.   As the rotor blades rotate, an outer cylinder that defines a flow path of airflow generated in the drive shaft direction is fixed to the heat treatment furnace, and the first vent and the second are spaced apart from the outer cylinder in the axial direction. The heat treatment apparatus according to any one of claims 1 to 4, wherein a vent is opened, and the first and second vents are displaced from each other by approximately 90 ° in a circumferential direction of the outer cylinder.

Images