JP2014196854A - Heat treatment furnace - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat treatment furnace capable of sufficiently closing a passing port for a treated object which is formed between heat treatment chambers.SOLUTION: In a heat treatment furnace for heat treating a treated object, a passing port through which the treated object passes is formed on a partition wall provided in a furnace body. The heat treatment furnace further includes a partition door for opening and closing the passing port, a storage part for storing the partition door in opening of the passing port, and a lifting and lowering mechanism for lifting and lowering the partition door. The partition door is supported by the lifting and lowering mechanism via a connection member fixed on the partition door, a position adjusting mechanism which holds the connection member to be movable only in a prescribed range, and a supporting member for supporting the position adjusting mechanism.

Description

  The present invention relates to a heat treatment furnace for heat-treating an object to be treated, which is a steel material such as automobile parts.

  Conventionally, for example, to-be-treated objects made of steel such as automobile parts are used as a heat treatment furnace, and are provided with a plurality of heat treatment chambers (a preheating chamber, a carburizing chamber, a diffusion chamber, a descending chamber, etc.). There is known a gas carburizing furnace that continuously performs pre-heat treatment, carburizing treatment, diffusion treatment, temperature lowering treatment, etc. while moving (see Patent Documents 1 and 2).

In the heat treatment furnaces as shown in Patent Documents 1 and 2, a passage opening for allowing the object to be processed to pass through is provided in a wall provided between adjacent heat treatment chambers. Further, the passage opening is configured to be opened and closed by a partition door. Thus, by partitioning each heat treatment chamber by an openable / closable partition door to form a closed space, atmosphere control (control of CP (carbon potential), composition, temperature, etc.) of each heat treatment chamber is suitably performed.

  In a heat treatment furnace having a plurality of treatment chambers, the atmosphere of each heat treatment chamber is controlled independently so as to be different. For example, when the preheating chamber and the carburizing chamber are provided adjacent to each other, the CP of the preheating chamber and the CP of the carburizing chamber have different values. Therefore, the partition door needs to be configured to sufficiently close the passage opening.

JP2003-240440 JP2008-209060

However, in the conventional heat treatment furnaces typified by Patent Documents 1 and 2, since the heat treatment performed by each treatment chamber is different, the temperature in each adjacent heat treatment chamber may be different. Under such circumstances, The partition door partitioning each heat treatment chamber is deformed by thermal expansion. Moreover, the deformation | transformation by thermal expansion of a partition door will arise also by the temperature difference between a partition door storage part and the inside of a heat treatment furnace. That is, after the partition door is closed, the partition door is deformed with time, so even if the heat treatment chambers are well partitioned in the initial stage, there is a gap in the upper part or side part of the passage opening due to the deformation. As a result, there is a problem that the passage opening is not sufficiently blocked. Therefore, the gas in the heat treatment chamber may easily move between the treatment chambers through the gap, and the atmosphere control in each heat treatment chamber is restricted.
Furthermore, in order to suppress the generation of gaps at the passage opening, for example, when the device configuration is such that the partition door is forcibly adhered to the furnace body, distortion occurs in the drive section of the furnace body or the partition door, resulting in equipment failure. May occur.

  Specifically, for example, when a preheating chamber and a carburizing chamber are provided adjacent to each other in a general gas carburizing furnace, if the CP of the carburizing chamber is increased (for example, about 1.0% to 1.2%), There is a possibility that the efficiency of the carburizing process can be increased, and the processing time of the entire continuous gas carburizing process can be shortened and improved. However, as described above, when the passage opening between the adjacent preheating chamber and the carburizing chamber is not sufficiently closed due to the expansion of the partition door, when the CP of the carburizing chamber is raised, the CP of the preheating chamber also rises. Therefore, there is a problem in the processing process. Further, an extra processing gas is required and energy efficiency is deteriorated. For these reasons, it is necessary to close as much as possible the passage openings provided between the processing chambers.

  In view of the above circumstances, an object of the present invention is to provide a heat treatment furnace capable of sufficiently closing a passage opening of an object to be processed provided between a plurality of heat treatment chambers.

  In order to solve the above-described problem, according to the present invention, a heat treatment furnace for heat-treating an object to be processed, the partition wall provided in the furnace body is provided with a passage port through which the object to be processed passes, and the passage A partition door that opens and closes a mouth; a storage portion that houses the partition door when the passage opening is opened; and a lifting mechanism that lifts and lowers the partition door; and a connection member fixed to the partition door, and the connection There is provided a heat treatment furnace in which the partition door is supported by the elevating mechanism via a position adjusting mechanism that holds the member so as to move within a predetermined range and a support member that supports the position adjusting mechanism.

The elevating mechanism is configured to elevate and lower the partition door along a substantially vertical direction between a closed position that closes the passage opening and an opening position that is above the closed position and opens the passage opening. May be.

The lifting mechanism may be a motor and a ball screw. The elevating mechanism may be a zip chain lifter.

  The interior of the furnace body and the interior of the storage chamber provided in the storage portion may be spatially blocked from each other by a seal member.

  The support member and the position adjusting mechanism may be coupled via a plurality of layers of heat insulating materials.

  The partition door includes a door main body made of a heat insulating material, a metal edge covering provided around the outside of the door main body, a lower ear portion attached to a lower portion of the partition door, and both the partition doors. You may comprise from the side ear part attached to an edge.

  A preheating chamber for performing preheating on the object to be processed, a carburizing chamber for performing carburizing and diffusion on the object to be processed after the preheating, and a temperature lowering process on the object to be processed after the carburizing and diffusion And the passage opening may be provided between the preheating chamber and the carburizing chamber and between the carburizing chamber and the descending greenhouse.

  ADVANTAGE OF THE INVENTION According to this invention, the heat processing furnace which can fully block | close the passage opening of the to-be-processed object provided between the some heat processing chambers etc. is provided.

It is a schematic sectional drawing of heat processing equipment. It is a longitudinal cross-sectional view of a passage opening and a partition door. It is a cross-sectional view of a passage opening. It is the figure which looked at the passage and the partition door from the X direction. It is the longitudinal cross-sectional view which cut | disconnected the passage port by the perpendicular surface (YZ surface) perpendicular | vertical with respect to the X direction. It is a schematic enlarged view of a position adjusting mechanism, a top plate, and a support member that have been constructed with a three-layer heat insulating material. In an Example, it is a graph which shows the result of having measured the temperature in a support member, the temperature in the internal space of a storage chamber, and the temperature in the storage part surface, respectively.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present specification and drawings, components having substantially the same functional configuration are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 1 is a schematic longitudinal sectional view of a heat treatment facility 1 according to an embodiment of the present invention, and specifically shows the structure of a continuous carburizing and quenching facility. As shown in FIG. 1, the heat treatment facility 1 is to be processed while transporting a workpiece W, which is a steel product such as an automobile part, in a transport direction D along the X direction (lateral direction in the figure, substantially horizontal direction). A heat treatment furnace 3 for treating the body W in a high temperature state and a quenching processing unit 4 for performing oil cooling (oil quenching treatment) of the workpiece W are provided. The heat treatment furnace 3 is a treatment furnace that performs gas carburization including, for example, preheat treatment, carburization treatment, diffusion treatment, and temperature lowering treatment. The quenching processing unit 4 includes an oil tank chamber 50 provided with an oil tank 52 below the interior, and includes an opening / closing door 51 for carrying out the workpiece W from the quenching processing unit 4.

  In the furnace body 10 of the heat treatment furnace 3, as a plurality of treatment chambers, a preheating chamber 11 that performs preheat treatment (temperature increase treatment) of the workpiece W, and a carburization chamber 12 (carburization diffusion chamber) that performs carburization treatment and diffusion treatment. A descending greenhouse 13 for performing a temperature lowering process after the diffusion process is arranged in order from the upstream side in the transport direction D. On the entrance side of the furnace body 10, there is provided a carry-in entrance 21 including an openable / closable door 22 for carrying the workpiece W into the furnace body 10 (preheating chamber 11) from the outside of the quenching treatment equipment 1. 10 is provided with a loading / unloading port 25 having an openable / closable door 26 for unloading the workpiece W from the furnace body 10 (falling greenhouse 13) and loading it into the quenching processing unit 4.

  Inside the furnace body 10, partition walls 27 and 28 are provided between the preheating chamber 11 and the carburizing chamber 12, and between the carburizing chamber 12 and the descending chamber 13. Passing ports 31 and 32 through which the workpiece W moves between the processing chambers are provided. Each passage port 31 and 32 is opened in a substantially rectangular shape (when opened), and partition doors 37 and 38 that can be freely opened and closed are provided. That is, the atmosphere of each processing chamber of the preheating chamber 11, the carburizing chamber 12, and the descending chamber 13 can be partitioned by closing the passage ports 31 and 32 with the partition doors 37 and 38. The detailed configurations of the passage ports 31 and 32 and the partition doors 37 and 38 will be described later with reference to the drawings. In addition, a roller conveyor 40 including a plurality of rollers 40 a is provided as a transport mechanism for transporting the workpiece W under the furnace body 10. The roller conveyor 40 has a configuration in which a plurality of rollers 40a are arranged side by side in the X direction at the lower part in the furnace body 10, and the work W is placed on the upper surface of each roller and conveyed. Further, the preheating chamber 11, the carburizing chamber 12, and the descending greenhouse 13 are provided with a stirring mechanism 42 such as a fan for stirring the atmosphere inside each, and a heater (not shown) for adjusting the internal temperature.

  The furnace body 10 has a three-layer structure in which a heat insulating layer 62 is laminated along the inner surface of the housing layer 61, and further, a refractory layer 63 is provided along the inner surface of the heat insulating layer 62. The housing layer 61 is made of, for example, metal, and the heat insulating layer 62 is formed of a heat insulating material such as microtherm (manufactured by Nippon Microtherm). The fireproof layer 63 is formed of, for example, ceramic fiber (ceramic fiber blanket). Ceramic fiber is a fiber made of a material mainly composed of alumina and silica, for example, has high heat resistance and heat insulation, and is flexible and lightweight, has good workability and workability, and is inexpensive and available. There are features such as easy.

Below, the structure of the passage 31 and the partition door 37 is demonstrated with reference to FIGS. In addition, since the passage opening 31 and the partition door 37 and the passage opening 32 and the partition door 38 are the same structures, the passage opening 31 and the partition door 37 are illustrated and demonstrated here.
2 is a longitudinal sectional view of the passage opening 31 and the partition door 37, and FIG. 3 is a transverse sectional view of the passage opening 31 (II section in FIG. 2). 4 is a view (cross-section II-II in FIG. 2) of the passage port 31 and the partition door 37 viewed from the X direction (preheating chamber 11 side), and FIG. 5 is a vertical view of the passage port 31 perpendicular to the X direction. The longitudinal cross-sectional view (III-III cross section in FIG. 2) cut | disconnected by the surface (YZ surface) is shown. 2 to 5 show a state where the passage port 31 is closed, that is, a state where the partition door 37 is lowered.

  As illustrated in FIGS. 2 to 4, the passage port 31 opens along the YZ plane. Two rollers 40 a are arranged at the lower edge of the passage port 31. The two rollers 40a are provided one by one at positions facing each other in the X direction across a groove (lower holding groove 71a described later) that holds the lower edge of the partition door 37 when the passage port 31 is closed. The upper portions of the rollers 40 a are exposed at the bottom of the passage port 31.

  In addition, a holding groove 71 (described later) that holds a side edge portion or a lower portion (a side ear portion 104 or a lower ear portion 103 described later) of the partition door 37 at the opening edge portion (both side edge portion and lower edge portion) of the passage port 31. Lower holding groove 71a and side holding groove 71b) are provided. An insertion outlet 72 that allows the partition door 37 to pass through is provided at the upper edge of the passage opening 31, and a storage section 73 that houses the partition door 37 is provided above the insertion outlet 72. The door 37 is configured to be stored in the storage portion 73.

  As shown in FIGS. 2 and 5, the insertion outlet 72 is formed between the upper edge portion of the passage port 31 and the storage portion 73 so as to vertically penetrate the ceiling portion of the furnace body 10. . The storage portion 73 has a structure in which a storage chamber 82 is formed inside the storage portion casing 81. A heat insulating member 85 is provided on the bottom surface of the housing part casing 81, and the housing part 73 is insulated from the inside of the furnace body 10 by a four-layer structure of the housing layer 61, the heat insulating layer 62, the fireproof layer 63, and the heat insulating member 85. It has a structure. Further, a seal member 86 such as a graphite packing is installed between the heat insulating member 85 and a position adjusting mechanism 90 to be described later. With the seal member 86, the inside of the storage chamber 82 is closed when the passage port 31 is closed. The space and the internal space of the furnace body 10 are configured to be spatially blocked. In addition, a heat insulating layer (not shown) may be provided on the inner surface of the housing casing 81.

  The upper edge portion of the partition door 37 is connected to a connecting member 88 including a connecting shaft 88a and a connecting head 88b, and the connecting head 88b is held by the position adjusting mechanism 90. The position adjusting mechanism 90 has a structure having a substantially rectangular parallelepiped internal space, and a hole through which the connecting shaft 88a passes is formed on the lower surface thereof. The connection head 88b has a structure (so-called loose-fit structure) that is held inside the position adjustment mechanism 90 in the storage chamber 82 so as to be movable in the vertical direction (Z direction) by a predetermined range.

In addition, the position adjustment mechanism 90 is supported by a support member 92 that is, for example, a support shaft above the top plate 91, and the support member 92 penetrates to the upper side of the storage portion 73 and is connected to the lifting mechanism 98. ing. That is, the power of the elevating mechanism 98 is transmitted to the partition door 37 via the support member 92, the position adjusting mechanism 90, and the connecting member 88, and the partition door 37 is movable up and down by the operation of the elevating mechanism 98. To do. The elevating mechanism 98 is composed of, for example, a motor and a ball screw.

  In the present embodiment, as shown in FIGS. 4, 5, etc., two connecting members 88 (a connecting shaft 88 a and a connecting head 88 b) are connected to the upper edge of the partition door 37, and the position adjusting mechanism 90. Also, two configurations corresponding to the number of connecting members 88 are shown. However, the number of the connecting members 88 and the position adjusting mechanisms 90 is not limited to this, and these configurations can be appropriately changed as long as the partition door 37 can be supported and raised / lowered appropriately.

  Here, when the passage port 31 is closed (that is, when the partition door 37 is closed), when the lower portion of the partition door 37 is held in the holding groove 71, the position adjusting mechanism 90 is provided and the connection head 88b is within a predetermined range. Therefore, the partition door 37 is also movable by a predetermined range in the vertical direction (Z direction).

  As shown in FIGS. 3 to 5, the partition door 37 is provided at a substantially rectangular door main body 101, an edge cover 102 that covers the four-sided peripheral edge of the door main body 101, and a lower end portion of the partition door 37. It comprises a lower ear portion 103 and a side ear portion 104 provided at the side edge of the partition door 37. As the material of the door body 101, it is desirable to use a material having high heat insulation and heat resistance, and for example, the same material as the fireproof layer 63, that is, ceramic fiber or the like may be used. In this case, the door body 101 can be reduced in weight, and the operating power of the elevating mechanism 98 when the partition door 37 is opened and closed can be reduced. Further, as the material of the edge covering body 102, it is desirable to use a material having mechanical properties such as higher strength, hardness, rigidity and the like than the door body 101. For example, a steel material such as SUS may be used.

  The lower ear portion 103 is provided at the lower part of the partition door 37 via the edge covering body 102, and the side ear portion 104 is provided at the both side edges (both side portions) of the partition door 37 via the edge covering body 102. Yes. The lower ear portion 103 is provided so as to spread downward (Z direction) from the lower surface of the edge covering body 102, and the side ear portion 104 is directed laterally (Y direction) from the side surface of the edge covering body 102. It is provided to spread.

Here, the side ear portion 104 is provided so that the width of the side ear portion 104 in the Y direction gradually increases as it goes upward. That is, the edge portion of the side ear portion 104 is provided along a direction inclined with respect to the Z direction so as to gradually move away from the edge covering body 102 toward the outside. Moreover, the side ear | edge part 104 is provided substantially parallel with respect to the groove | channel back part (groove bottom part) of the side part holding groove | channel 71b mentioned later.

As a material of each ear part (lower ear part 103, side ear part 104), those having high heat resistance, and further having mechanical properties such as higher strength, hardness, rigidity, etc. than the door body 101 and the partition wall 27, In other words, it is desirable to use one having less deformability than the door body 101 and the partition wall 27. In this case, when each ear | edge part and the partition wall 27 are made to contact, each ear | edge part will not deform | transform substantially but will hold | maintain a plate-shaped shape.

Further, as shown in FIG. 5, a lower holding groove 71 a for holding the lower ear portion 103 when the partition door 37 is closed is formed in the lower portion of the passage port 31. In addition, a side holding groove 71b for holding the side ear 104 when the partition door 37 is closed is formed on the side of the passage port 31. The side portion holding groove 71b has a groove shape that is concavely formed outward from the side portion of the passage port 31, and the depth from the side portion of the passage port in the Y direction gradually becomes deeper as it goes upward. It is formed to become. In addition, the opening width of the lower holding groove 71a and the side holding groove 71b is constant in any part, and is, for example, larger than the interval between the rolls 40a of the roller conveyor 40.

  As shown in FIGS. 2 and 5, a cover 76 is provided at the bottom of the lower holding groove 71 a provided at the lower portion of the passage port 31. Further, as shown in FIG. 5, a similar covering 76 is also provided in the groove rear portion of the side holding groove 71 b. That is, the partition wall 27 includes a wall main body 110 and a cover 76 that can be removed from the wall main body 110 and can be replaced. The cover 76 is provided over both the lower holding groove 71a and the side holding groove 71b. It has been. The covering 76 provided at the back of the lower holding groove 71a is provided so that the upper surface is substantially horizontal, and the lower ear 103 of the partition door 37 is brought into contact with the passage 31 when the passage 31 is closed. Moreover, the covering body 76 provided in the back part of the side part holding groove 71b is provided along the inclination of the side part holding groove 71b. In the present embodiment, the thickness of the covering 76 is constant, and the width is long enough to cover the holding groove 71.

  As mentioned above, although the structure of the passage 31 and the partition door 37 was demonstrated with reference to FIGS. 2-5, in the heat processing furnace 3 concerning this Embodiment, the structure of the passage 32 and the partition door 38 is also the said passage 31. And since it has the same apparatus structure as the structure of the partition door 37, the description is abbreviate | omitted in this specification.

  Next, the heat processing with respect to the to-be-processed object W in each processing chamber in the heat processing equipment 1 shown in FIG. 1 is demonstrated. However, since the continuous carburizing process performed in the heat treatment facility 1 is a heat treatment that is generally performed conventionally, a detailed description of the processing steps in each processing chamber is omitted in this specification.

In the heat treatment furnace 3, a supply path (not shown) is supplied to each processing chamber (preheating chamber 11, carburizing chamber 12, and descending chamber 13) from the outside according to the processing to be performed with rich gas, metamorphic gas, air, and nitrogen. ) And an exhaust path (not shown) for exhausting the supplied gas is also provided in each processing chamber.

First, before the object to be processed W is carried into the heat treatment facility 1, the atmosphere (temperature, pressure, composition, CP (carbon potential), etc.) in each processing chamber is adjusted to predetermined processing conditions. For example, the temperature of the preheating chamber 11 is about 930 ° C., the temperature of the carburizing chamber 12 is about 930 ° C. to 950 ° C., and the temperature of the greenhouse 13 is about 850 ° C. The CP value of the preheating chamber 11 is about 0.8%, the CP value of the carburizing chamber 12 is about 0.8% to 1.2%, and the CP value of the greenhouse 13 is about 0.8%.

Adjustment of the atmosphere in the preheating chamber 11, the carburizing chamber 12, the descending chamber 13, and the quenching processing unit 4 is performed by adjusting the heating value of the heater (not shown), the supply flow of the rich gas, the supply flow of the modified gas, the supply flow of air, and the supply of nitrogen gas This is done by adjusting the flow rate, the amount of exhaust at each location, and the like. In addition, when adjusting the atmosphere, the passages 31 and 32 and the loading / unloading port 25 are closed. Thereby, the atmospheres of the preheating chamber 11, the carburizing chamber 12, the descending greenhouse 13, and the quenching processing unit 4 can be controlled independently, and are efficiently set to predetermined conditions.

Next, in a state where the atmosphere in the preheating chamber 11, the carburizing chamber 12, the descending greenhouse 13, and the quenching processing unit 4 is adjusted to predetermined processing conditions, the door 22 of the carry-in entrance 21 is opened, and the workpiece W is loaded. It is carried into the preheating chamber 11 through the port 21 and the door 22 of the carry-in port 21 is closed. And the to-be-processed object W carried in to the heat processing furnace 3 is sequentially conveyed by the roller conveyor 40 to the preheating chamber 11, the carburizing chamber 12, and the descending greenhouse 13, and preheating in the preheating chamber 11, the carburizing diffusion process in the carburizing chamber 12, The temperature lowering process in the descending greenhouse 13 is sequentially performed.

When the workpiece W is moved from the preheating chamber 11 to the carburizing chamber 12, the passage port 31 is opened. Specifically, the partition door 37 is raised by the operation of the elevating mechanism 98, and sufficient opening is performed so that the workpiece W can pass through the passage port 31. And after the to-be-processed object W passes the passage port 31 and is carried in to the carburizing chamber 12, the partition door 37 is dropped by operation | movement of the raising / lowering mechanism 98, and the passage port 31 is obstruct | occluded. Similarly, also when moving the to-be-processed object W from the carburizing chamber 12 to the descending greenhouse 13, the partition door 38 is raised / lowered and the passage port 32 is opened / closed.

In addition, after moving the to-be-processed body W from the preheating chamber 11 to the carburizing chamber 12, another to-be-processed body W can be carried in into the preheating chamber 11 from the carrying-in entrance 21, and can be processed continuously. That is, in the heat treatment furnace 3, a plurality of objects to be processed W can be continuously processed in parallel. Even in the case where a plurality of workpieces W are processed in this way, since the passage ports 31 and 32 are closed by the partition doors 37 and 38 when the workpiece W is carried in, each process An indoor heat treatment atmosphere can be suitably maintained.

When the temperature lowering process in the descending greenhouse 13 is completed, the loading / unloading port 25 is opened, and the workpiece W is moved to the quenching processing unit 4 through the loading / unloading port 25. Then, in the state where the loading / unloading port 25 and the open / close door 51 are closed, the workpiece W is immersed in an oil tank 52 in which oil is stored as a cooling liquid, so that an oil quenching process is performed. After completion of the quenching process, the opening / closing door 51 is opened, and the workpiece W is carried out of the quenching processing unit 4. As described above, a series of processes on the workpiece W in the heat treatment facility 1 is completed.

In the continuous carburizing process for the object to be processed W described above, since the heat treatment furnace 3 processes the plurality of objects to be processed W in parallel, the opening and closing of the passage ports 31 and 32 are repeatedly performed. As described above, the insides of the preheating chamber 11, the carburizing chamber 12, and the descending greenhouse 13 have different atmospheres, and in order to perform each treatment efficiently, avoid atmospheric interference between the treatment chambers as much as possible. Or it needs to be suppressed.

In this regard, according to the heat treatment furnace 3 described in the present embodiment, as shown in FIGS. 2 to 5, the partition doors 37 and 38 are moved up and down via the connecting member 88, the position adjusting mechanism 90, and the support member 92. The structure is connected to the mechanism 98. When closing the passage ports 31 and 32, the lower ear portion 103 of the partition door 37 is held in the lower holding groove 71a, and the side ear portion 104 is held in the side portion holding groove 71b, so that there is no gap. 31 and 32 are sufficiently closed.

On the other hand, when the passage ports 31 and 32 are closed by the partition doors 37 and 38, the internal temperatures of the processing chambers adjacent to each other (for example, the preheating chamber 11 and the carburizing chamber 12) are different, or the inside of the storage unit 73. Due to the temperature difference between the (storage chamber 82) and the inside of the furnace body 10, the partition doors 37 and 38 are thermally expanded and deformed, and a gap is formed in the passage ports 31 and 32, which may not be sufficiently closed. In particular, when the position adjusting mechanism 90 described above is not provided, the heat insulating member 85 and the connecting member 88 (the connecting head 88b) disposed above the partition doors 37 and 38 at the time of closing (that is, the lower portion of the storage portion 73). There are gaps between them. In such a case, in the heat treatment furnace 3 according to the present embodiment, the position adjusting mechanism 90 is provided as a configuration for supporting the partition doors 37 and 38, and even if the partition doors 37 and 38 are thermally expanded, the connection is performed. Since the head 88b moves only within a predetermined range inside the position adjusting mechanism 90, the deformation of the partition doors 37 and 38 is absorbed, and a problem that a sufficient blockage cannot be realized due to a gap in the passage ports 31 and 32 is avoided. be able to. Furthermore, since the contact area between the connection head 88b and the position adjustment mechanism 90 is small when the partition doors 37 and 38 are closed, heat radiation from the connection member 88 to the outside of the furnace body 10 is suppressed.

  That is, in the heat treatment furnace 3 according to the present embodiment, the passage ports 31 and 32 are always closed by avoiding and absorbing the deformation of the partition doors 37 and 38 due to the temperature difference between the processing chambers, and the respective processing chambers. The atmosphere can be controlled independently and efficiently. As a result, each processing chamber can be accurately maintained in a predetermined processing condition atmosphere, and the efficiency of each processing can be improved and the processing time can be shortened. In addition, since the blockage is sufficiently performed, the processing gas (enrich gas, metamorphic gas, etc.) supplied to each processing chamber is effectively used, and the energy efficiency is improved.

  In addition, as shown in FIG. 2, the heat treatment furnace 3 according to the present embodiment has a configuration in which a heat insulating member 85 is provided between the storage unit 73 (storage unit casing 81) and the upper surface of the furnace body 10, A seal member 86 is provided between the position adjusting mechanism 90 and the heat insulating member 85 inside the storage portion 73 (that is, the internal space of the storage chamber 82). Therefore, compared with the conventional heat treatment furnace (for example, patent document 2) provided with the furnace body of the three-layer structure, the heat insulation of heat treatment furnace 3 inside (namely, each process chamber interior) and the accommodating part 73 improves, Leakage of the atmosphere inside the furnace body into the storage chamber 82 is suppressed, and an increase in the internal temperature of the storage chamber 82 is also suppressed. That is, the amount of heat released from the inside of the heat treatment furnace 3 can be reduced as compared with the conventional case, and the thermal efficiency of the heat treatment equipment 1 can be improved. The point that the amount of heat released from the inside of the heat treatment furnace 3 to the storage portion 73 is greatly reduced will also be described in the embodiments described later.

  As mentioned above, although an example of embodiment of this invention was demonstrated, this invention is not limited to the form of illustration. It is obvious for those skilled in the art that various modifications or modifications can be conceived within the scope of the idea described in the claims, and these naturally belong to the technical scope of the present invention. It is understood.

  For example, in the said embodiment, the continuous gas carburizing equipment is illustrated and demonstrated as the heat processing equipment 1, and the steel material is illustrated as the to-be-processed object W. FIG. Specifically, the heat treatment furnace 3 is described as having a preheating chamber 11, a carburizing chamber 12, and a descending greenhouse 13. However, the configuration of the present invention is not limited to such a form, and can be applied to a heat treatment furnace and atmosphere heat treatment equipment for performing various heat treatments such as a nitriding furnace, an annealing furnace, and a sintering furnace.

  Further, as shown in the above embodiment, when the connecting member 88 and the position adjusting mechanism 90 are used, the heat of the connecting member 88 heated in the furnace body 10 is not easily transferred to the support member 92 and the lifting mechanism 98. Therefore, a relatively low heat resistance such as a zip chain lifter (registered trademark, Enomoto Chain Co., Ltd.) can be used as the lifting mechanism 98. In that case, compared with the case where a ball screw etc. are used, the height of the raising / lowering mechanism 98 can be reduced significantly and the heat processing equipment 1 which can be installed also in the space with a low ceiling is implement | achieved.

  Further, in the configuration of the position adjusting mechanism 90 and the support member 92 described in the above embodiment, for example, the top plate 91 and the support member 92 are connected via a heat insulating material having a three-layer structure in order to further improve the heat insulation. A structure is also conceivable. As the heat insulating material, for example, Microtherm (manufactured by Nippon Microtherm) is used.

FIG. 6 is a schematic enlarged view of the position adjusting mechanism 90, the top plate 91, and the support member 92 in which the heat insulating material 110 (110a to 110c) having a three-layer structure is applied. In the present modification shown in FIG. 6, the top plate 91 is composed of two top plates 91 a and 91 b, and three layers of heat insulating materials 110 are fixed by bolts 112 between the top plates 91 a and 91 b. According to the present heat insulating material modification, heat in the heat treatment furnace 3 that becomes high temperature during processing is less likely to be transmitted to the support member 92 and the storage chamber 82 as compared with the conventional equipment, and the temperature rise of the storage portion 73 is suppressed. The heat in the heat treatment furnace 3 can be prevented from being radiated to the outside of the furnace.

  In the description of the above-described embodiment and its modifications, the blockage between the processing chambers by the partition doors 37 and 38 used in this specification does not necessarily indicate a strict sealed state, for example, a gas atmosphere. It is sufficient that the atmosphere is sufficiently cut off between the processing chambers as a furnace.

In the heat treatment furnace according to the present embodiment described above and its modifications, in order to confirm how much the heat radiation from the furnace body to the storage part of the partition door has been reduced, the present inventors have compared with a conventional heat treatment furnace. In the heat treatment furnace according to the present invention, three temperatures of the support member located in the storage part of the partition door, the internal space of the storage room, and the surface of the storage part were measured. As a conventional heat treatment furnace, a furnace having the structure described in Patent Document 2 is used, and as the heat treatment furnace according to the present invention, the three-layer heat insulating material described in the above modification is provided above the position adjusting mechanism. Measurement was performed using Moreover, the place which performs a measurement was a storage part of a partition door provided between the preheating chamber and the carburizing chamber, and the measurement was performed in a state where the heat treatment was actually performed on the workpiece.

  FIG. 7 is a graph showing the results of measuring the temperature at the support member, the temperature at the interior space of the storage chamber, and the temperature at the surface of the storage section, and the comparative example shows the measurement results in a conventional heat treatment furnace, The Example has shown the measurement result in the heat processing furnace concerning this invention.

  As shown in FIG. 7, compared with the measurement result of the comparative example, the measurement result of the example is about 294.5 ° C. for the support member, about 257.6 ° C. for the internal space of the storage chamber, and about 25 ° C. for the surface of the storage section. , Each became a low temperature. This indicates that the heat treatment furnace according to the present invention has less heat radiation to the storage part located outside the furnace body than the conventional heat treatment furnace structure, and is particularly located inside the storage part. The temperature difference is significant in the support member and the storage room interior space. That is, from the results shown in FIG. 7, it was found that in the heat treatment furnace according to the present invention, the amount of heat released from the furnace at the place where the passage opening and the partition door were provided was reduced, and the thermal efficiency was improved. .

  The present invention can be applied to a heat treatment furnace that heat-treats an object to be processed, which is a steel material such as automobile parts.

DESCRIPTION OF SYMBOLS 1 ... Heat treatment equipment 3 ... Heat treatment furnace 4 ... Quenching process part 10 ... Furnace body 11 ... Preheating chamber 12 ... Carburizing chamber 13 ... Falling-out chamber 27, 28 ... Partition wall 31, 32 ... Passage 37, 38 ... Partition door 40 ... Roller Conveyor 71 ... Holding groove 72 ... Insertion outlet 73 ... Storage part 82 ... Storage chamber 85 ... Heat insulation member 86 ... Seal member 88 ... Connection member 88a ... Connection shaft 88b ... Connection head 90 ... Position adjustment mechanism 92 ... Support member 98 ... Lifting mechanism D: Conveying direction W: Object to be processed

Claims (8)

A heat treatment furnace for heat-treating a workpiece,
A partition wall provided in the furnace body is provided with a passage port through which the object to be processed passes,
A partition door for opening and closing the passage opening;
A storage section for storing the partition door when the passage opening is opened;
An elevating mechanism for elevating and lowering the partition door,
The partition door is moved up and down via a connecting member fixed to the partition door, a position adjusting mechanism that holds the connecting member so as to move within a predetermined range, and a support member that supports the position adjusting mechanism. Heat treatment furnace supported by the mechanism. The elevating mechanism is configured to elevate and lower the partition door along a substantially vertical direction to a closed position that closes the passage opening and an opening position that is above the closing position and opens the passage opening. The heat treatment furnace according to claim 1. The heat treatment furnace according to claim 1, wherein the elevating mechanism is a motor and a ball screw. The heat treatment furnace according to claim 1, wherein the lifting mechanism is a zip chain lifter. The heat treatment furnace according to any one of claims 1 to 4, wherein the interior of the furnace body and the inside of the storage chamber provided in the storage part are spatially blocked from each other by a seal member. The heat treatment furnace according to claim 1, wherein the support member and the position adjusting mechanism are connected via a plurality of layers of heat insulating materials. The partition door includes a door main body made of a heat insulating material, a metal edge covering provided around the outside of the door main body, a lower ear portion attached to a lower portion of the partition door, and both the partition doors. The heat-treatment furnace in any one of Claims 1-6 comprised from the side ear part attached to an edge part. A preheating chamber for preheating the object to be treated;
A carburizing chamber for performing a carburizing process and a diffusion process on the object to be processed after the pre-heat treatment;
A temperature-decreasing greenhouse that performs a temperature-decreasing process on the object to be processed after the carburizing process and the diffusion process,
The heat treatment furnace according to any one of claims 1 to 7, wherein the passage is provided between the preheating chamber and the carburizing chamber and between the carburizing chamber and the descending chamber.

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