JP6425433B2 - Heat treatment apparatus and heat treatment method - Google Patents

Description

  The present invention relates to a heat treatment apparatus and a heat treatment method for subjecting a work to a heat treatment related to carburizing treatment.

  In order to improve the wear resistance of a low carbon steel material or the like (hereinafter referred to as "work"), it is general to carry out a carburizing treatment in which carbon is solid-solved in the surface layer of the work. Usually, when carburizing treatment is performed, treatment such as heating or quenching of a work is also performed. A series of heat treatments related to this type of carburizing treatment include one for each treatment such as a continuous carburizing apparatus that performs each treatment continuously while conveying a work, a heat treatment apparatus for heat treatment, and a heat treatment apparatus for carburization treatment It is carried out using a batch type carburizing apparatus which is performed by a heat treatment apparatus.

  In the case of a batch type carburizing apparatus, each heat treatment apparatus is provided with a partition door which opens and closes a work transfer port of the heat treatment room when the work is carried into and out of the heat treatment room. Then, by closing the partition door, the internal atmosphere of the heat treatment chamber and the external atmosphere are shut off, whereby the inside of the heat treatment chamber is maintained in an atmosphere suitable for each heat treatment.

  The length of loading and unloading of the workpiece and the opening and closing time of the partition door affect the productivity, so these times are required to be as short as possible. As a related technology for realizing this, there is a melting furnace described in Patent Document 1. In this melting furnace, the lid 34 fixed to the carriage 44 and the crucible 1 (corresponding to a work) move integrally as the carriage 44 moves. With such a structure, the opening of the processing chamber 32 can be covered with the lid 34 at the same time the crucible 1 is carried into the processing chamber 32. Thereby, the processing chamber 32 is sealed.

JP, 2002-327988, A

  However, if the workpiece is heat-treated many times, foreign matter may adhere to the cover that covers the opening of the heat-treatment chamber or the contact surface with the lid on the heat-treatment chamber (container 33 in Patent Document 1) side. . In this case, in the apparatus structure described in Patent Document 1, when the crucible is carried into the processing chamber 32, the lid 34 is a container in a state in which foreign matter is sandwiched between the lid 34 and the container 33. It is pressed to 33. As a result, the lid 34 may be deformed. If the lid is deformed, the sealing property of the heat treatment chamber can not be maintained, so replacement of the lid member or the like is required, and the productivity is lowered.

  The present invention has been made in view of the above circumstances, and it is an object of the present invention to suppress deformation of a lid that seals a heat treatment chamber and to improve productivity.

The present invention for solving the above-mentioned problems is a heat treatment apparatus for subjecting a work to a heat treatment related to carburizing treatment, which comprises a heat treatment chamber capable of sealing, a mounting table provided below the heat treatment chamber and on which the work is placed Description: A lifting rod connected to the mounting table is provided, and a lid constituting a bottom portion of the heat treatment chamber is attached to the lifting rod, and the lid rotates in the vertical direction with respect to the mounting table. It is characterized in that the position of the body is adjusted .

  According to the present invention, since the lid constituting the bottom of the heat treatment chamber is screwed to the elevating rod, the lid moves downward when a downward force acts on the lid. For this reason, even when foreign matter bites between the lid and the lower end of the side wall portion in contact with the lid when sealing the heat treatment chamber, the lid remains at the lower end of the side wall while the foreign matter bites. There is no pressure. This makes it possible to suppress the deformation of the lid.

The present invention according to another aspect is a heat treatment method for subjecting a work to a heat treatment related to carburizing, comprising a lift body for raising and lowering a mounting table provided below the heat treatment chamber, the lid forming the bottom of the heat treatment chamber The cover is mounted so that the position of the cover in the vertical direction with respect to the mounting table can be adjusted by rotating the cover, and before the work is carried into the heat treatment chamber, the cover according to the size of the work The position of the lid in the vertical direction with respect to the mounting table is adjusted by rotating the holder, and when the work is carried into the heat treatment chamber, the elevating rod is raised to seal the heat treatment chamber with the lid. Heat treatment is carried out.

  According to the present invention, it is possible to suppress the deformation of the lid which seals the heat treatment chamber. Thereby, the maintenance frequency of the lid can be reduced, and the productivity can be improved.

It is a schematic block diagram of the heat processing apparatus which concerns on embodiment of this invention. It is a top view which shows the shape of the mounting base which concerns on embodiment of this invention, and a conveyance arm. It is explanatory drawing which shows the heat processing method of the workpiece | work which concerns on embodiment of this invention. It is explanatory drawing which shows the heat processing method of the workpiece | work which concerns on embodiment of this invention. It is explanatory drawing which shows the heat processing method of the workpiece | work which concerns on embodiment of this invention. It is explanatory drawing which shows the heat processing method of the workpiece | work which concerns on embodiment of this invention. It is explanatory drawing which shows the heat processing method of the workpiece | work which concerns on embodiment of this invention. It is explanatory drawing which shows the heat processing method of the workpiece | work which concerns on embodiment of this invention. It is explanatory drawing which shows the heat processing method of the workpiece | work which concerns on embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present embodiment will be described based on a heat treatment apparatus that performs carburizing treatment of a work. In the present specification and the drawings, elements having substantially the same functional configuration will be assigned the same reference numerals and redundant description will be omitted.

  FIG. 1 is a schematic configuration view of a heat treatment apparatus 1 in the present embodiment. In FIG. 1, for convenience of explanation, the side wall on the front side of the drawing is not shown. As shown in FIG. 1, the heat treatment apparatus 1 in this embodiment includes a cylindrical heat treatment chamber 2 for carburizing the workpiece W, and a delivery chamber for delivering the workpiece W between the mounting table 20 and the transfer arm 30. It has three. The delivery chamber 3 is provided below the heat treatment chamber 2.

  Between the heat treatment chamber 2 and the delivery chamber 3, a transport port 4 for carrying in and transport the workpiece W is formed. The transfer port 4 is open except during heat treatment of the workpiece W, and the atmosphere of the heat treatment chamber 2 and the atmosphere of the delivery chamber 3 are in communication. Further, an opening 5 for carrying in and out the work W is formed on the side wall of the delivery chamber 3. An open / close door 6 for opening and closing the opening 5 is provided outside the side wall provided with the opening 5.

  The side wall 7 of the heat treatment chamber 2 is composed of an outer wall (hereinafter referred to as "side wall outer wall 7a") and a heat insulating material (hereinafter referred to as "side wall heat insulator 7b") provided on the inner side surface of the side wall outer wall 7a. It has a double structure. Further, the upper end and the lower end of the side wall portion outer wall 7 a are shaped to project inward of the heat treatment chamber 2. Similarly, the upper end and the lower end of the side wall heat insulating material 7 b also have a shape projecting inward of the heat treatment chamber 2. Further, the upper end and the lower end of the side wall heat insulating material 7b are in a state of projecting inward of the heat treatment chamber 2 with respect to the upper end and the lower end of the side wall outer wall 7a. That is, the upper end and the lower end of the side wall portion 7 have a stepped shape.

  Below the heat treatment chamber 2, a mounting table 20 for mounting the workpiece W is provided. The mounting table 20 is connected to the elevating rod 8. The elevating rod 8 is provided to penetrate the bottom of the delivery chamber 3 and is connected to an elevating device (not shown) that raises and lowers the elevating rod 8.

  The upper end of the lift rod 8 is threaded. A disc-like lid 10 constituting the bottom of the heat treatment chamber 2 is attached to the threaded portion 9. The lid 10 has a double structure including an outer wall (hereinafter, referred to as "lid outer wall 10a") and a heat insulating material (hereinafter, referred to as "lid thermal insulator 10b") as in the side wall portion 7. At the center of the lid outer wall 10a and the lid heat insulator 10b, a hole (not shown) to which internal thread processing is applied is formed. That is, the lid 10 is screwed to the elevating rod 8. Therefore, by rotating the lid 10, the position of the lid 10 with respect to the mounting table 20 can be adjusted.

  The diameter of the lid heat insulator 10b is smaller than the diameter of the lid outer wall 10a. That is, the peripheral edge of the lid 10 has a stepped shape. Further, the diameter of the lid outer wall 10a has a diameter substantially equal to the diameter of the protrusion side surface S1 of the side wall outer wall 7a. Further, the diameter of the lid heat insulator 10b is approximately equal to the diameter of the protrusion side surface S2 of the side wall heat insulator 7b.

  Therefore, when the mounting table 20 is raised, the step-shaped portion at the periphery of the lid engages with the step-shaped portion at the lower end of the side wall portion. Specifically, the side surface S3 of the lid outer wall 10a is in contact with the protrusion side surface S1 of the sidewall outer wall 7a, and the side surface S4 of the lid heat insulator 10b is in contact with the projection side surface S2 of the sidewall heat insulator 7b. The upper surface U2 of the lid outer wall 10a abuts on the lower surface U1 of the projecting portion of the material 7b. Thus, even when a large gap is generated in any of the contact surfaces, the sealing property of the heat treatment chamber 2 is maintained by the other contact surfaces by the plurality of contact surfaces between the side wall portion 7 and the lid 10. can do. That is, the sealing property of the heat treatment chamber 2 can be enhanced by making the shape of the peripheral edge of the lid 10 a shape that engages with the step shape at the lower end of the side wall portion.

  Moreover, the ceiling part 11 of the heat processing room 2 also has a double structure which consists of an outer wall (henceforth "ceiling part outer wall 11a") and a heat insulating material (henceforth "ceiling part heat insulation material 11b"). The engagement structure of the ceiling portion 11 and the side wall portion 7 is also similar to the engagement structure of the lid 10 and the side wall portion 7. In addition, the ceiling part 11 is comprised so that removal from the heat processing chamber 2 is possible, and, thereby, the maintainability is improved.

  Next, the mounting table 20 and the transfer arm 30 will be described. FIG. 2 is a plan view showing the shapes of the mounting table 20 and the transfer arm 30 in the present embodiment. In FIG. 2, the outer shape of the workpiece W is indicated by a broken line.

  As shown in FIG. 2, the mounting table 20 is integrally formed with a central disk 21 and three workpiece mounting portions 22 radially protruding from the disk 21. The angles formed by the respective work placement portions 22 are equal to each other (120 ° in the present embodiment), and mounting table pins 23 for supporting the work W are provided at the tip end portions of the respective work placement portions 22. There is. That is, the work W is supported at three points by the mounting table pin 23.

  Further, the tip end portion 31 of the transfer arm 30 has a three-forked shape in plan view, and the tip end of the three-forked portion protrudes from the transfer arm main body 32 so as to be directed to the center of the disc 21 of the mounting table 20 (Work support 33). Further, a gap is formed between the tips of the side work support portions 34 protruding from both sides of the transfer arm main body 32. That is, an opening 35 is provided at the distal end portion 31 of the transfer arm 30. The size of the opening 35 is such a size that the side work support portion 34 does not contact the lift rod 8 connected to the mounting table 20 when the transfer arm 30 extends and retracts, for example, the distance between the tips of the side work support portion 34 moves up and down The size is larger than the diameter of the rod 8.

  Each work support portion 33 of the transfer arm 30 is provided to support the work W between the work placement portions 22 of the placement table 20 in a plan view. The angles formed by the workpiece support portions 33 are equal to each other (120 ° in the present embodiment). A transfer arm pin 36 for supporting the work W when transferring the work W is provided at the tip of each work support portion 33, and the work W is supported at three points by the transfer arm pin 36.

  The heat treatment apparatus 1 in the present embodiment is configured as described above. Although not shown in the drawings, the heat treatment apparatus 1 has a structure necessary for general carburizing treatment such as a heating mechanism, a carburizing gas introduction mechanism, and an exhaust mechanism. The delivery chamber can be a vacuum atmosphere, and may be provided with an exhaust port for forming a vacuum atmosphere, a vacuum gauge, or the like.

  Next, a carburizing method using the heat treatment apparatus 1 will be described. In addition, in the heat processing apparatus 1 shown to FIGS. 3-9, illustration of a part of component is abbreviate | omitted.

  First, as shown in FIG. 3, in the heating step which is a pre-process of the carburizing step, the work W heated to near the carburizing temperature is supported by the transfer arm 30 and carried into the delivery chamber 3.

  Subsequently, as shown in FIG. 4, the mounting table 20 is raised. Thus, the workpiece W is delivered from the transfer arm 30 to the mounting table 20. Thereafter, as shown in FIG. 5, the transfer arm 30 retracts, and the open / close door 6 of the delivery chamber 3 is closed.

  Subsequently, as shown in FIG. 6, the mounting table 20 is raised, and the workpiece W is carried into the heat treatment chamber 2. At the same time, the step-shaped portion at the periphery of the lid screwed to the elevating rod 8 engages with the step-shaped portion at the lower end of the side wall portion 7 of the heat treatment chamber 2. Thereby, the heat treatment chamber 2 is sealed.

  At this time, the lifting rod 8 does not stop the lifting operation until the predetermined lifting amount is reached. For this reason, for example, even when foreign matter is caught between the upper surface U2 of the lid outer wall 10a and the protrusion lower surface U1 of the side wall heat insulating material 7b, the elevating rod 8 continues to ascend. However, in the heat treatment apparatus 1 in the present embodiment, since the lid 10 is screwed to the elevating rod 8, the lid 10 moves below the elevating rod 8 by the reaction force received from the foreign object caught. That is, the lid 10 is not pressed against the lower surface U1 of the protrusion of the side wall heat insulating material 7b while the foreign matter bites. Thereby, the deformation of the lid 10 can be suppressed.

  In addition, by moving the lid 10 downward, a gap is generated between the lid 10 and the lower end of the side wall portion 7, and the sealing property of the heat treatment chamber 2 is lowered. At this time, it is possible to detect that a gap is generated between the lid 10 and the lower end of the side wall portion, for example, by a sensor or the like that detects the sealing property of the heat treatment chamber 2. In this case, after the heat treatment of the workpiece W is temporarily interrupted and foreign substances are removed, the lid 10 can be returned to a predetermined position by rotating the lid 10.

  Subsequently, after the work W is carried into the heat treatment chamber 2, a carburizing gas is introduced to carry out the carburizing process. After completion of the carburizing treatment, as shown in FIG. 7, the mounting table 20 is lowered, and the open / close door 6 of the delivery chamber 3 is opened. Thereafter, as shown in FIG. 8, the transfer arm 30 advances into the delivery chamber, and as shown in FIG. 9, the work W is transferred from the mounting table 20 to the transfer arm 30.

  Thus, a series of carburizing processes according to the present embodiment are completed. Thereafter, the work W carried out of the delivery chamber 3 is subjected to hardening treatment and the like in another heat treatment apparatus 1.

  As described above, according to the present embodiment, since the lid 10 constituting the bottom of the heat treatment chamber 2 is screwed to the elevating rod 8, foreign matter bites when the mounting table 20 is raised. It is possible to suppress the deformation of the lid 10. As a result, time spent on maintenance such as replacement of the lid member can be reduced, and productivity can be improved.

  This effect is particularly noticeable when performing processing with an emphasis on product quality in which only a small amount (for example, one) of the workpiece W is processed in one processing. This is because, when a small amount of processing is performed, the frequency of carrying the work W into the heat treatment chamber 2 increases, and the frequency of contact between the upper surface of the lid 10 and the lower end of the side wall portion 7 inevitably increases. That is, when a small amount of processing is performed, deformation of the lid 10 is likely to occur, but the deformation can be suppressed in the heat treatment apparatus 1 in the present embodiment.

Further, if the lid 10 is screwed to the elevating rod 8 as in the present embodiment, the lid 10 is rotated according to the size (height, thickness) of the workpiece W to be heat-treated. , Position of the lid 10 can be adjusted. As a result, it is Netsusho sense to Rukoto the work W of various sizes without changing the height of the heat treatment chamber 2.

  Although the preferred embodiments of the present invention have been described above, the present invention is not limited to such examples. It is apparent that those skilled in the art can conceive of various changes or modifications within the scope of the technical idea described in the claims, and the technical scope of the present invention is also natural for them. It is understood to belong to

  For example, in the above embodiment, the carburizing process is performed by the heat treatment apparatus 1, but the heat treatment performed by the heat treatment apparatus 1 is not limited to the carburizing process. Other treatments relating to the carburizing treatment such as heating and cooling may be performed. Further, in the above-described embodiment, although the upper end portion of the lifting and lowering rod 8 is screwed, the entire lifting and lowering rod may be threaded.

  Further, in the above embodiment, although the lid 10 is shaped to engage with the step-shaped portion at the lower end of the side wall portion 7, the lid 10 and the side wall portion 7 may not have the step shape. Moreover, it is not necessary to use a heat insulating material for the lid 10. Furthermore, the lid 10 may not have a double structure. That is, if the lid 10 is screwed to the elevating rod 8, it is possible to suppress the deformation of the lid 10 caused by the biting of foreign matter.

However, if the lid 10 has a multi-layered structure, the contact surface between the lid 10 and the lower end of the side wall increases when the shape of the peripheral edge of the lid 10 engages with the step-shaped portion at the lower end of the side wall. The sealing performance of the heat treatment chamber 2 can be improved. In addition, in the case of a multilayer structure, the heat insulating property of the heat treatment chamber 2 can be further improved by using at least one layer as a heat insulating material. Furthermore, the unnecessary atmosphere gas can be prevented from flowing into the delivery chamber 3 from the heat treatment chamber 2. When a vacuum atmosphere is used, the degree of vacuum can be stably maintained.

  The present invention can be applied to the carburizing treatment of a work.

DESCRIPTION OF SYMBOLS 1 Heat treatment apparatus 2 Heat treatment room 3 Delivery room 4 Conveyance opening 5 Opening 6 Opening / closing door 7 Side wall part 7a Side wall part outer wall 7b Side wall part heat insulating material 8 Lifting rod 9 Threaded part 10 Lid 10a Lid outer wall 10b Lid insulation 11 Ceiling part 11a ceiling outer wall 11b ceiling heat insulating material 20 mounting table 21 disk 22 work mounting unit 23 mounting table pin 30 transfer arm 31 transfer arm tip 32 transfer arm main body 33 workpiece support 34 side workpiece support 35 opening 36 transfer Arm pin S1 Side wall protrusion of the outer wall side S2 Side wall protrusion of the heat insulator side S3 Side wall of the lid outer wall S4 Side surface of the lid heat insulator U1 Side wall protrusion of the heat insulator lower surface U2 Top surface of the lid outer wall W Work

Claims (6)

A heat treatment apparatus for subjecting a work to a heat treatment according to a carburizing treatment,
A heat treatment chamber that can be sealed
A mounting table provided below the heat treatment chamber for mounting a workpiece;
And a lifting rod connected to the mounting table,
A lid constituting a bottom of the heat treatment chamber is attached to the elevating rod ,
The heat treatment apparatus, wherein the position of the lid in the vertical direction with respect to the mounting table is adjusted by rotating the lid .   The heat treatment chamber according to claim 1, wherein the heat treatment chamber has a multilayer structure, and the lower end of the side wall portion of the heat treatment chamber has a step shape, and the periphery of the lid engages with the step shape. apparatus.   The heat treatment apparatus according to claim 1, wherein the heat treatment chamber has a multilayer structure, and at least one layer is formed of a heat insulating material. A heat treatment method for subjecting a work to a heat treatment related to carburizing treatment,
The lid which constitutes the bottom of the heat treatment chamber is rotated on a lift rod which raises and lowers the mounting table provided below the heat treatment chamber, and the position of the lid in the vertical direction with respect to the mounting plate is increased by rotating the lid. Attached to be adjusted,
Before loading the workpiece into the heat treatment chamber, the position of the lid in the vertical direction with respect to the mounting table is adjusted by rotating the lid according to the size of the workpiece;
A heat treatment method, wherein when the work is carried into the heat treatment chamber, the elevating rod is raised, and the heat treatment is performed by sealing the heat treatment chamber with the lid.   The heat treatment chamber is sealed by the lid body having a multi-layered structure, the lower end of the side wall portion of the heat treatment chamber has a step shape, and the periphery of the lid is engaged with the step shape. The heat treatment method as described in 4.   The heat treatment method according to claim 4 or 5, wherein the heat treatment chamber has a multilayer structure, and at least one layer is formed of a heat insulating material.

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