TWI606223B - Heat treatment furnace - Google Patents

Description

Heat treatment furnace

The present invention relates to a heat treatment furnace.

Conventionally, as a heat treatment furnace for heat-treating a workpiece, it is known to include a member in which the furnace body is subjected to heat treatment, and a conveyance path for transporting the workpiece to or from the furnace body. For example, Patent Document 1 describes a heating device including: heating a main body portion to heat an object to be heated; and a conveyance path for heating the main body portion or conveying the object to be heated from the heating main body portion. In the heating device, the external airflow intrusion preventing portion that is inclined at an upper portion away from the heating main body portion and having a cavity formed therein is provided in the transport path. By providing the external airflow entering the blocking portion, the gas in the heating main body portion having a higher temperature than the outside air rapidly flows along the wall between the external airflow intrusion preventing portions, and the inflow of the outside air can be suppressed. Moreover, it also has an effect of suppressing the outflow of gas to the outside air.

[Prior patent documents] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2008-128544

However, the main purpose of the airflow entering the blocking portion as described in Patent Document 1 is to prevent the inflow of the outside air and suppress the outflow of the ambient gas to the outside. The effect is not sufficient. Further, it is also desired to further enhance the effect of suppressing the inflow of outside air.

The present invention has been developed in order to solve such a problem, and its main object is to sufficiently suppress the inflow of the outside air into the furnace body or the outflow of the ambient gas to the outside. The outflow of the ambient gas to the outside can be further suppressed.

The heat treatment furnace of the present invention is a heat treatment furnace for heat-treating a workpiece to be placed on a carrier sheet, comprising: a furnace body for internally heat-treating the workpiece; and a first conveyance path for external use The carrier plate on which the workpiece is placed is transported between the furnace body; the gas supply means supplies an inert gas as an ambient gas to the inside of the furnace body; and the heating means is to make the atmosphere gas inside the furnace body The upper space forming portion is provided on the vertical side of the first conveyance path, and is formed in an upper space that is open at the lower lower side and communicates with the inside of the first conveyance path, and a lower space forming portion. The lower side of the first conveyance path is formed on the lower side of the first conveyance path, and is formed in a lower space that is open on the vertical side and communicates with the inside of the first conveyance path. The lower space intake means draws air into the lower space.

In the heat treatment furnace of the present invention, an inert gas is supplied to the furnace body, and the ambient gas of the furnace body is heated to a higher temperature than the outside air. Therefore, when there is an ambient gas that has flowed out from the furnace body to the first conveyance path, the ambient gas tends to stay in the upper space provided on the vertical side of the first conveyance path. Thereby, the ambient gas is suppressed from flowing out to the outside through the first conveyance path. Further, by the retention of the environmental gas, the upper space is liable to be in a state of being higher than the inside of the furnace body. Thereby, the force of the ambient gas flowing out from the inside of the furnace body is pushed back to the inside of the furnace body, thereby suppressing the outflow of the ambient gas. Further, by inhaling the lower space provided on the lower side of the first conveyance path, the space from the upper space passes through the first conveyance path to the lower space. The flow of gas. Therefore, this flow acts as an air curtain, and the first conveyance path between the outside and the inside of the furnace body can suppress the outflow and the inflow of the gas. According to the above, the inflow of the outside air to the furnace body or the outflow of the ambient gas to the outside can be sufficiently suppressed. Here, the first conveyance path may be used to carry the carrier sheet from the outside into the furnace body, or may be used to carry the carrier sheet from the furnace body to the outside. Further, the gas supply means may be a combination of the heating means. For example, the gas supply means may be used to supply an inert gas having a temperature higher than that of the outside air. Further, the lower space air suction means and the gas supply means may be configured to separately perform the suction of the lower space and the supply of the inert gas in order to maintain the upper space at a higher pressure than the inside of the furnace body. In this way, the force to push back the ambient gas flowing out of the inside of the furnace body to the inside of the furnace body is easy to act.

The heat treatment furnace of the present invention may further include a second conveyance path for conveying the conveyance path of the carrier on which the workpiece is placed between the first conveyance path and the furnace body, and carrying the conveyance path The direction length L is 100 mm or more and 1000 mm or less. By setting the transport direction length L to 100 mm or more, it is possible to further suppress the outflow of the atmosphere gas of the furnace body.

In the heat treatment furnace of the present invention, the third conveyance path may be provided, and the third conveyance path may be configured to convey the carrier plate on which the workpiece is placed between the outside and the first conveyance path; When the carrier plate is transported, the size of the gap in the vertical direction of the carrier plate in the third transport path is the gap height H, and the minimum value Hmin of the gap height H is more than 0 mm and 50 mm or less. Since the smaller the minimum value Hmin is, the gas is more difficult to pass through the third transport path, so that the inflow of the outside air to the furnace body or the outflow of the ambient gas to the outside can be further suppressed.

In the heat treatment furnace of the present invention, a direction perpendicular to the conveyance direction of the carrier sheet and parallel to the horizontal direction may be a left-right direction, and when the carrier sheet is transported by the first conveyance path, the first conveyance path may be taken from the first conveyance path. The gap between the left end and the left and right direction of the carrier plate is set to the left gap width W _L , and when the carrier plate is transported by the first transport path, the right end of the first transport path to the carrier plate When the size of the gap in the left-right direction is the right gap width W _R , the left gap width W _L and the right gap width W _R are both in the range of 10 mm or more and 150 mm or less. By setting both the left gap width W _L and the right gap width W _R to 10 mm or more, the flow rate of the gas from the upper space to the lower space through the first conveyance path becomes large. Therefore, the flow is easy to act as an air curtain, which can suppress the outflow and inflow of gas. In addition, by setting the left gap width W _L and the right gap width W _R to 150 mm or less, it is possible to suppress the gas from flowing in the direction along the conveyance path in the first conveyance path, so that the outflow and the inflow of the gas can be further suppressed.

The heat treatment furnace according to the present invention may further include: a second conveyance path for conveying the carrier sheet on which the workpiece is placed between the first conveyance path and the furnace body; and the second conveyance means having a configuration a plurality of second transport rollers are disposed on the second transport path, and the carrier plate is transported in a predetermined transport direction by the second transport roller; and the flow suppressing member is disposed between the second transport rollers adjacent to the transport direction The gap suppressing gas flows in the vertical direction. In this manner, when the ambient gas from the furnace passes through the second conveyance path, it is less likely to flow below the second conveyance roller, and the ambient gas from the furnace body is easily guided to the upper space. Therefore, the outflow of the ambient gas to the outside can be more suppressed.

The heat treatment furnace according to the present invention may further include: a second conveyance path for conveying the load on the workpiece between the first conveyance path and the furnace body; The first transport means includes a plurality of first transport rollers disposed in the first transport path, and the carrier is transported in a predetermined transport direction by the first transport roller; and the second transport means has The plurality of second conveyance rollers disposed on the second conveyance path are spaced apart from each other by the first conveyance roller, and the carrier sheet is conveyed in the conveyance direction by the second conveyance roller. In this manner, when the ambient gas from the furnace passes through the second conveyance path, it is less likely to flow below the second conveyance roller, and the ambient gas from the furnace body is easily guided to the upper space. Therefore, the outflow of the ambient gas to the outside can be more suppressed.

The heat treatment furnace according to the present invention may further include: a third conveyance path for conveying the carrier sheet on which the workpiece is placed between the outside and the first conveyance path; and the third conveyance means having the third conveyance means disposed thereon The third conveyance roller of the third conveyance path is conveyed by the third conveyance roller in a predetermined conveyance direction; and the flow suppressing member is restrained by the gap between the third conveyance rollers adjacent to the conveyance direction The gas circulates in the vertical direction.

The heat treatment furnace according to the present invention may further include: a third conveyance path for conveying the carrier sheet on which the workpiece is placed between the outside and the first conveyance path; and the first conveyance means disposed thereon a plurality of first conveyance rollers of the first conveyance path, wherein the carrier plate is conveyed in a predetermined conveyance direction by the first conveyance roller; and the third conveyance means is disposed at a smaller interval than the first conveyance roller The third transport roller of the third transport path is transported by the third transport roller in the transport direction.

In the heat treatment furnace of the present invention, the upper space forming portion may be formed in the upper space inclined in a direction away from the furnace body. When the ambient gas having a higher temperature than the outside air flows out of the furnace body, the flow direction of the ambient gas is The farther away from the furnace body. Therefore, by the upper space being inclined in the direction away from the furnace body, the ambient gas from the furnace body is easily guided to the upper space, and the outflow to the outside can be further suppressed.

In this case, the upper space forming portion may have a partition member that is inclined in a direction in which the upper portion is away from the furnace body, and divides the upper space into a direction along the conveying direction of the carrier plate. Multiple compartment spaces. In this manner, by the plurality of compartment members being inclined in the direction away from the furnace body, the ambient gas from the furnace body is easily guided to the upper space. In this case, the plurality of compartment spaces may also communicate with each other above in the upper space. In this manner, when the ambient gas from the furnace body flows to the first conveyance path, the ambient gas passes through any one of the plurality of compartment spaces, flows to the upper space in the upper space, and then flows from the other compartment space therefrom. After that, the flow back to the furnace body is likely to occur, and the effect of returning the ambient gas to the furnace body and suppressing the outflow to the outside is enhanced.

In the heat treatment furnace of the present invention, the lower space forming portion may be formed in the lower space inclined in a direction in which the lower portion approaches the furnace body. When the external airflow reaches the first transport path, since the temperature of the ambient gas of the furnace body is relatively high, the flow direction of the external air becomes the direction in which the furnace body is lowered. Therefore, since the lower space is inclined in the lower direction toward the furnace body, the outside air is easily guided to the lower space, and the inflow to the furnace body can be further suppressed.

10‧‧‧heat treatment furnace

11‧‧‧ furnace body

11a‧‧‧Handling space

12‧‧‧ front end

13‧‧‧ rear end face

14, 15‧‧‧ openings

16, 17‧‧‧ gas supply port

18‧‧‧Exit

19‧‧‧Exhaust port

20‧‧‧heater

21‧‧‧In-furnace conveying roller

22, 24‧‧‧ gas supply device

26‧‧‧Flow adjustment valve

28‧‧‧Exhaust valve

30‧‧‧1st way of transport

34‧‧‧1st transport mechanism

35‧‧‧1st conveying roller

40‧‧‧2nd transport route

44‧‧‧2nd transport mechanism

45‧‧‧2nd conveying roller

50‧‧‧3rd way of transport

52‧‧‧Transportation port

54‧‧‧3rd transport mechanism

55‧‧‧3rd carrying roller

60‧‧‧Top Space Formation Department

62‧‧‧ outer wall

63‧‧‧The space above

64a, 64b‧‧‧ compartment components

65a~65c‧‧‧ Compartment space

70‧‧‧The space formation department below

72‧‧‧ outer wall

73‧‧‧Lower space

74a, 74b‧‧‧ compartment components

75a~75c‧‧‧ Compartment space

76‧‧‧ suction port

77‧‧‧Aspirator

80‧‧‧Circulation suppression components

81‧‧‧ pillar

90‧‧‧ Controller

95‧‧‧Loading board

96‧‧‧Processed objects

110‧‧‧Test furnace

D1, D2‧‧ ‧ line segments

Fig. 1 is a longitudinal sectional view of a heat treatment furnace 10.

Fig. 2 is a view A of Fig. 1.

Figure 3 is a cross-sectional view taken along line B-B of Figure 2.

Fig. 4 is a perspective view of the flow suppressing member 80.

Figure 5 is a longitudinal sectional view of the test furnace 110.

Next, an embodiment of the present invention will be described using the drawings. Fig. 1 is a longitudinal sectional view showing a heat treatment furnace 10 according to an embodiment of the present invention. Fig. 2 is a view A of Fig. 1. Figure 3 is a cross-sectional view taken along line B-B of Figure 2. In addition, in FIG. 2 and FIG. 3, the object 96 to be placed on the carrier plate 95 is not shown. The heat treatment furnace 10 includes a furnace body 11, a first conveyance path 30, a second conveyance path 40, a third conveyance path 50, an upper space forming portion 60, a lower space forming portion 70, and a controller 90. The heat treatment furnace 10 is configured as a roller oven which conveys a carrier plate 95 on which a plurality of objects 96 are placed, in a processing space 11a of the furnace body 11, and faces the object to be treated. 96 was heat treated.

The furnace body 11 is a heat insulating structure having a substantially rectangular parallelepiped shape, and has a processing space 11a for a space inside the chamber, and openings 14 and 15 which are respectively formed on the front end surface 12 of the furnace body (the left end surface of the first drawing) and the rear. The end surface 13 (the right end surface of Fig. 1) serves as an entrance and exit to the processing space 11a from the outside. In the processing space 11a, a plurality of in-furnace conveyance rollers 21 are disposed from the opening 14 to the opening 15 in a predetermined conveyance direction. Further, in the present embodiment, the conveyance direction is a direction from the front to the rear (the direction from the left to the right in the first drawing). By the rotation of the in-furnace conveyance roller 21, the carrier sheet 95 on which the plurality of workpieces 96 are placed passes through the processing space 11a from the opening 14, and is conveyed to the opening 15. Further, in the processing space 11a, a plurality of heaters 20 are disposed on the top and bottom of the furnace body 11 so as to sandwich the plurality of in-furnace conveyance rollers 21 from above and below. The heater 20 is arranged such that the growth direction is a direction perpendicular to the conveyance direction (left-right direction), and is disposed along the conveyance direction. Several. The heater 20 heats the ambient gas that has passed through the workpiece 96 or the processing space 11a in the processing space 11a, and is configured as a ceramic heater such as a SiC heater. Further, it is not limited to the heater 20, and it is only required to be a heating device that can heat-treat the workpiece 96 such as a gas burner.

Further, on the side of the rear end surface 13 of the bottom portion of the furnace body 11, a gas supply port 16 for supplying the ambient gas to the processing space 11a connected to the gas supply device 22 is formed. On the side of the front end surface 12 of the bottom of the furnace body 11, a gas supply port 17 for supplying the ambient gas to the processing space 11a connected to the gas supply device 24 is formed. In addition, the gas supply devices 22 and 24 are configured as a hot air generating furnace, and are supplied to the processing space 11a as an ambient gas, for example, by heating an inert gas such as nitrogen gas to a temperature higher than the outside air. On the top end surface 12 side of the furnace body 11, a flow outlet 18 which is connected to the flow rate adjusting valve 26 and allows the ambient gas of the processing space 11a to flow out is formed. The flow rate adjustment valve 26 is connected to the gas supply devices 22 and 24 via a pipe, and circulates the ambient gas of the processing space 11a as the suction gas of the gas supply devices 22 and 24. In addition, components (for example, oxygen, water, and the like) other than the inert gas may be removed by a gas system of the flow rate adjusting valve 26 by a filter or the like, and then supplied to the gas supply devices 22 and 24. Behind the outflow port 18 at the top of the furnace body 11, an exhaust port 19 is formed which is connected to the exhaust valve 28 and can discharge the ambient gas of the processing space 11a. Further, the arrangement of the outflow port 18 and the exhaust port 19 is not limited to this. For example, the exhaust port 19 may be disposed closer to the distal end surface 12 than the outflow port 18.

The first conveyance path 30, the second conveyance path 40, and the third conveyance path 50 are the conveyance paths of the carrier 95 and the workpiece 96 from the outside to the opening 14 of the furnace body 11. These moving paths are from the outside to the furnace body 11, according to the third transportation path. 50. The first conveyance path 30 and the second conveyance path 40 are arranged in this order. Hereinafter, the description will be given in this order.

The third conveyance path 50 is configured to convey the load-bearing plate 95 and the workpiece 96 from the outside to the conveyance path of the first conveyance path 30, and is configured as a pipe. The third conveyance path 50 has a conveyance port 52 that is an inlet for the outside, and is disposed in the conveyance direction to convey the third conveyance roller 55 of the third conveyance mechanism 54 of the carrier 95 and the flow suppression member 80. The third transport mechanism 54 includes a plurality of third transport rollers 55 and a motor (not shown) that rotationally drives the third transport roller 55. The plurality of (three in the present embodiment) third transport rollers 55 are disposed in the third transport path 50 at equal intervals along the transport direction. The flow suppressing member 80 is a plate-shaped member and is disposed such that the surface is parallel to the conveying direction. Fig. 4 is a perspective view of the flow suppressing member 80. In the flow suppression member 80, a plurality of (two in the present embodiment) are arranged so as to fill a gap in the conveyance direction (front-rear direction) of the adjacent third conveyance roller 55 (see FIG. 1, FIG. 3, and FIG. 4). Figure). In addition, the flow suppressing member 80 is supported by the two pillars 81 that are fixed to the bottom side while penetrating the bottom of the third transport path 50 up and down, and is supported on both sides in the left-right direction (see FIG. 4).

The first conveyance path 30 is configured to convey the load-bearing plate 95 and the workpiece 96 from the third conveyance path 50 to the conveyance path of the second conveyance path 40, and is configured as a pipe. In the first conveyance path 30, the first conveyance roller 35 of the first conveyance mechanism 34 that conveys the conveyance plate 95 in the conveyance direction is disposed. The first transport mechanism 34 includes a plurality of first transport rollers 35 and a motor (not shown) that rotationally drives the first transport roller 35. The plurality of (three in the present embodiment) first transport rollers 35 are disposed in the first transport path 30 at equal intervals along the transport direction.

The upper space forming portion 60 is provided in the first transport path 30 Vertically on the side. The upper space forming portion 60 has a box-shaped outer wall 62 that is opened in the downward direction. The space inside the outdoor wall 62 is formed in an upper space 63 that is open at the lower side and communicates with the inside of the first conveyance path 30. The outer wall 62 is formed to have an airtight structure except for the opening in the downward direction, and the outflow, the inflow, and the like of the gas that does not pass through the outside of the first conveyance path 30 hardly occur. Further, the wall portion of the front wall (the left side of the first drawing) and the wall portion of the rear side (the right side of the first drawing) are inclined in the direction in which the upper portion is away from the furnace body 11. Thereby, the upper space 63 becomes a space which is inclined in the direction away from the furnace body 11 in the upper part. Further, the upper space forming portion 60 includes the partition members 64a and 64b which are inclined in the direction away from the furnace body 11 in the inside of the outer wall 62. The partition members 64a and 64b are flat members arranged in this order from the front to the rear, and both ends in the left-right direction (not shown) are attached to the left and right wall portions of the outer wall 62 by, for example, welding. The partition member 64a, the partition member 64b, the wall portion on the front side of the outer wall 62, and the wall portion on the rear side of the outer wall 62 are inclined only at the same angle θ1 from the front toward the upper side. The angle θ1 of the inclination is not particularly limited as long as it is more than 0° to less than 90°. For example, the angle θ1 may be set to 30 to 60°. Thereby, one of the upper spaces 63 is divided into compartment spaces 65a to 65c by the partition members 64a and 64b. The compartment space 65a is a space defined by the wall portion of the outer wall 62 and the partition member 64a. The compartment space 65b is a space defined by the compartment member 64a and the compartment member 64b. The compartment space 65c is a space defined by the partition wall member 64b and the wall portion behind the outer wall 62. These compartment spaces 65a to 65c are all open in the first conveyance path 30 below. Further, none of the compartment members 64a, 64b are in contact with the top of the outer wall 62. Therefore, the compartment spaces 65a to 65c are connected to each other above the upper space 63 (near the top of the outer wall 62).

Further, the lower space forming portion 70 is provided on the vertically lower side of the first transport path 30. The lower space forming portion 70 has a box-shaped outer wall 72 that is open in the upper direction. A space inside the outdoor wall 72 is formed in a lower space 73 that is open on the vertical side and communicates with the inside of the first conveyance path 30. The outer wall 72 is formed to have an airtight structure except for the opening in the upward direction, and the outflow, the inflow, and the like of the gas that does not pass through the outside of the first conveyance path 30 hardly occur. Further, the wall portion of the outer wall 72 (the left side of the first drawing) and the wall portion of the rear side (the right side of the first drawing) are inclined in a direction in which the lower portion is closer to the furnace body 11 (the upper portion is away from). Thereby, the lower space 73 becomes a space which is inclined in a direction in which the lower portion approaches the furnace body 11. Further, the lower space forming portion 70 includes the partition members 74a and 74b which are inclined in the lower direction of the furnace body 11 in the inner portion of the outer wall 72. The partition members 74a and 74b are flat members arranged in this order from the rear toward the front, and both ends in the left-right direction (not shown) are attached to the left and right wall portions of the outer wall 72 by, for example, welding. The partition member 74a, the partition member 74b, the wall portion on the front side of the outer wall 72, and the wall portion on the rear side of the outer wall 72 are inclined only at the same angle θ2 from the rear toward the lower side. The angle θ2 of the inclination is not particularly limited as long as it is more than 0° to less than 90°. For example, the angle θ2 may be 30 to 60°. Thereby, one of the lower spaces 73 is divided into the compartment spaces 75a to 75c by the partition members 74a and 74b. The compartment space 75a is a space defined by the wall portion behind the outer wall 72 and the partition member 74a. The compartment space 75b is a space defined by the compartment member 74a and the compartment member 74b. The compartment space 75c is a space defined by the wall portion of the partition member 74b and the outer wall 72. Each of the compartment spaces 75a to 75c is open above the first conveyance path 30. Further, none of the compartment members 74a, 74b are in contact with the top of the outer wall 72. Therefore, the compartment spaces 75a to 75c are below the lower space 73 (outer wall) Near the bottom of 72) are connected to each other. Further, one of the first conveyance rollers 35 is disposed in each of the opening portions above the compartment spaces 75a to 75c. Further, at the bottom of the outer wall 72, an intake port 76 connected to the air suction means 77 for sucking the lower space 73 is formed. The air suction device 77 sucks the gas in the lower space 73 through the intake port 76 and exhausts the gas.

The second conveyance path 40 is configured to convey the load-bearing plate 95 and the workpiece 96 from the first conveyance path 30 to the conveyance path of the opening 14 of the furnace body 11 and to form a pipe. In the second conveyance path 40, the second conveyance roller 45 and the flow suppression member 80 of the second conveyance mechanism 44 of the conveyance direction conveyance plate 95 are disposed. The second transport mechanism 44 includes a plurality of second transport rollers 45 and a motor (not shown) that rotationally drives the second transport roller 45. The plurality of (three in the present embodiment) second transport rollers 45 are disposed in the second transport path 40 at equal intervals along the transport direction. The flow suppressing member 80 is the same member as that disposed in the third transport path 50. The flow suppression member 80 is disposed in plural (two in the present embodiment) so as to fill a gap between the adjacent conveyance directions (front and rear directions) of the second conveyance rollers 45. Further, the flow suppressing member 80 is supported by the two pillars 81 that are fixed to the bottom portion while penetrating the bottom of the second transport path 40 up and down, and is supported on both sides in the left-right direction (see FIG. 4).

Further, the first conveyance path 30 and the third conveyance path 50 are configured as continuous pipes. In the present embodiment, the line segment D1 connecting the distal end portion of the opening of the upper space forming portion 60 and the distal end portion of the opening of the lower space forming portion 70 is the boundary between the first transport path 30 and the third transport path 50. Similarly, the first conveyance path 30 and the second conveyance path 40 are configured as continuous pipes. In the present embodiment, the rear end portion of the opening of the upper space forming portion 60 is connected to the space below. The line segment D2 of the rear end portion of the opening of the intermediate portion 70 serves as a boundary between the first conveyance path 30 and the second conveyance path 40. Further, the second conveyance path 40 is configured such that the conveyance direction length L is 100 mm or more and 1000 mm or less. The transport direction length L is a distance between the opening 14 adjacent to the second transport path 40 and the first transport path 30. In the present embodiment, as shown in Fig. 1, the transport direction length L is a portion that is inclined from the open end (= front end surface 12) of the opening 14 to the outer wall 62 (the rear end portion of the opening of the upper space forming portion 60). The length of the direction of transport. Further, the upper ends of the first to third conveyance rollers 35, 45, and 55 are located at substantially the same height as the lower end of the conveyance port 52 and the lower end of the opening 14.

The controller 90 is constructed as a CPU-centric microprocessor. The controller 90 outputs control signals to the gas supply devices 22 and 24, and individually controls the supply amount or supply temperature of the inert gas to the furnace body 11 via the gas supply port 16 and the gas supply port 17. The controller 90 outputs a control signal to the flow rate adjusting valve 26, and controls the amount of gas circulated from the outflow port 18 to the gas supply device 22, the gas supply device 24, or outputs a control signal to the exhaust valve 28 to control the processing space. The amount of ambient gas discharged from 11a. Further, the controller 90 outputs a control signal to the air suction device 77 to control the intake air amount (suction rate) of the gas from the lower space 73 via the intake port 76. Further, the controller 90 outputs a control signal to the heater 20 to adjust the temperature of the processing space 11a or to the in-furnace conveyance roller 21, the first conveyance mechanism 34, the second conveyance mechanism 44, and the third conveyance mechanism 54. The illustrated motor outputs a drive signal to rotate the in-furnace conveyance roller 21, the first conveyance roller 35, the second conveyance roller 45, and the third conveyance roller 55.

The carrier plate 95 is constructed of a material having high corrosion resistance or heat resistance (for example, ceramics, etc.) in order to withstand the heat treatment of the workpiece 96 in the furnace body 11. to make. The carrier plate 95 is only required to be capable of placing and transporting the workpiece 96, and may be, for example, a flat plate shape or a mesh shape.

The workpiece 96 is subjected to heat treatment such as baking by heat from the heater 20 while passing through the furnace body 11. In the present embodiment, the workpiece 96 is a laminate in which a ceramic dielectric and an electrode are laminated (the size is, for example, 1 mm or less in length and width), and a wafer which becomes a ceramic capacitor after baking is used.

Next, a state in which heat treatment of the workpiece 96 is performed using the heat treatment furnace 10 configured in this manner will be described. First, the controller 90 operates a motor (not shown) to rotate the in-furnace conveyance roller 21, the first conveyance roller 35, the second conveyance roller 45, and the third conveyance roller 55, and energizes the heater 20 to heat it. The device 20 is hot. The rotational speed of each of the transport rollers is predetermined according to the time required for the heat treatment of the workpiece 96. The output of the heater 20 is predetermined based on the temperature (for example, about 1000 ° C or the like) at the time of heat treatment of the workpiece 96 in the processing space 11a. Then, the carrier sheet 95 on which the plurality of objects 96 are placed is prepared, and is gradually placed on the third conveyance roller 55 on the side of the conveyance port 52 of the third conveyance path 50. In the present embodiment, as shown in FIG. 2 and FIG. 3, the carrier sheet 95 is provided with a plurality of sheets (four sheets in the present embodiment) without gaps in the left-right direction (direction perpendicular to the conveyance direction). Each of the four carrier plates 95 is gradually placed on the third conveyance roller 55 in the front-rear direction without any gap. The carrier plate 95 placed on the third conveyance roller 55 is conveyed by the plurality of conveyance rollers, and the third conveyance path 50, the first conveyance path 30, and the second conveyance path 40 are conveyed in this order, and are guided from the opening 14 The sequence is gradually moved into the furnace body 11. In the third figure, the state in which four pieces of the left and right sides, three pieces of the front and the back, and three pieces are sequentially transported in this manner is shown. Then, the carrier plate 95 passes through the furnace body Between the insides of the 11th, the workpiece 96 is heat-treated, and then the workpiece 96 is carried out from the opening 15 together with the carrier 95. In this manner, in the heat treatment furnace 10, the carrier sheet 95 on which the workpiece 96 is placed is sequentially conveyed, and the heat treatment is gradually performed by the heater 20.

Further, between the conveyance carrying plates 95, the controller 90 controls the gas supply device 22 to supply the inert gas into the furnace body 11, and controls the flow rate adjusting valve 26 and the exhaust valve 28 to allow the ambient gas to flow out of the furnace body 11. ,discharge. Further, the controller 90 controls the air suction device 77 to suck in the gas from the lower space 73. The amount (speed) of the supply and the inhalation is such that the processing space 11a can be held in a predetermined ambient gas, and may be predetermined by, for example, an experiment, or may be based on, for example, a temperature sensor (not shown). After the controller 90 takes out the information (temperature, etc.) of the processing space 11a, the controller 90 adjusts the supply amount and the like based on the information. Further, the gas supply device 24 is used in a case where the carrier plate 95 cannot be continuously supplied due to a certain failure, and the carrier plate 95 is interrupted in the conveyance path. When the carrier plate 95 does not exist, the space of the first conveyance path 30, the second conveyance path 40, and the third conveyance path 50 becomes wider, so that the outside air easily flows into the furnace body 11. Therefore, in this case, the controller 90 is configured to supply the inert gas from the gas supply device 24 to maintain the atmosphere in the processing space 11a. Further, instead of using the gas supply device 24, the supply amount from the gas supply device 22 may be increased.

Here, the gap between the carrier plate 95 and the conveyance path when the carrier plate 95 is conveyed will be described. In the present embodiment, in order to perform the heat treatment, the first transport path 30 is determined such that the minimum value Hmin, the left gap width W _L , and the right gap width W _R of the gap height H when the carrier plate 95 is transported are within a predetermined range. The shape of the second conveyance path 40 and the third conveyance path 50 or the shape and arrangement of the carrier plate 95. Hereinafter, these values will be described.

The gap height H is a size of a gap in the vertical direction of the carrier plate 95 in the third conveyance path 50 when the carrier sheet 95 is conveyed by the third conveyance path 50. Further, the minimum value of the gap height H in the third conveyance path 50 is the minimum value Hmin. Here, as shown in Fig. 1, the third conveyance path 50 of the present embodiment has a shape in which the height from the front (transport port 52) to the rear (portion of the line segment D1) is constant. Therefore, the gap height H when the carrier plate 95 is gradually conveyed in the third conveyance path 50 is the same at any position of the third conveyance path 50. Therefore, in the present embodiment, the minimum value Hmin is the same value as the gap height H (see Fig. 1 and Fig. 2). Further, the minimum value Hmin determined in this manner is preferably more than 0 mm and not more than 50 mm. Therefore, the top height of the third conveyance path 50 (the height from the upper end to the top of the third conveyance roller 55) or the thickness of the carrier plate 95 is preferably determined in such a manner that the minimum value Hmin is within the range. In addition, for example, when a part of the top of the third conveyance path 50 is lowered, or a plate-shaped member that protrudes from the top of the third conveyance path 50 to the lower side, the gap height of the support plate 95 when passing through the portion is H becomes smaller. In the case where the gap height H is not constant in the entire third transport path 50, the gap height H at the position where the gap in the vertical direction of the carrier plate 95 is small becomes the minimum value Hmin.

The left gap width W _L is the size of the gap from the left end of the first conveyance path 30 to the left-right direction of the carrier plate 95 when the carrier sheet 95 is conveyed by the first conveyance path 30. Further, when the plurality of carrier plates 95 are arranged to be transported in the left-right direction, the distance from the left end of the first conveyance path 30 to the nearest carrier plate 95 is defined as the left gap width W _L . Similarly, the right gap width W _R is the size of the gap from the right end of the first conveyance path 30 to the left-right direction of the carrier plate 95 when the carrier sheet 95 is conveyed by the first conveyance path 30. Further, when the plurality of carrier plates 95 are arranged to be transported in the left-right direction, the distance from the right end of the first conveyance path 30 to the nearest carrier plate 95 is defined as the right gap width W _R . Here, as shown in FIG. 3, the first conveyance path 30 of the present embodiment has a shape in which the height in the left-right direction from the front (portion of the line segment D1) to the rear (portion of the line segment D2) is constant. Therefore, the left gap width W _L and the right gap width W _R when the carrier plate 95 is gradually conveyed in the third conveyance path 50 are the same at any position of the first conveyance path 30. Further, the left gap width W _L and the right gap width W _R in this manner are preferably 10 mm or more and 150 mm or less in the entire first transport path 30. In other words, in the entire first transport path 30, it is preferable that the left gap width W _L and the right gap width W _{R are} separated from the range of 10 mm or more and 150 mm or less when the carrier plate 95 is transported. Therefore, the width of the first conveyance path 30 in the left-right direction, the width of the carrier plate 95 in the left-right direction, and the number of the left-right direction of the carrier plate 95 are determined in advance so that the left gap width W _L and the right gap width W _{R are} within the range. And so on. In addition, for example, the width of the first conveyance path 30 in the left-right direction is not fixed to the entire first conveyance path 30, or the carrier plate 95 is meandered in the first conveyance path 30, or the arrangement of the carrier 95 is not fixed. In the case of the first transport path 30, the left left gap width W _L and the right gap width W _R are different values. In this case, the left gap width W _L and the right gap width W _R are preferably in the range of 10 mm or more and 150 mm or less in the entire first transport path 30.

Here, the correspondence between the constituent elements of the present embodiment and the constituent elements of the present invention will be clarified. The carrier plate 95 of the present embodiment corresponds to the carrier plate of the present invention, and the workpiece 96 corresponds to the workpiece, and the furnace body 11 corresponds to the furnace body. The first conveyance path 30 corresponds to the first conveyance path, the gas supply device 22 corresponds to the gas supply means, the heater 20 and the gas supply device 22 correspond to the heating means, and the upper space forming portion 60 corresponds to the upper space forming portion, and the lower space is formed. The portion 70 corresponds to the lower space forming portion, and the air suction device 77 corresponds to the lower space air suction means. Further, the second transport mechanism 44 corresponds to the second transport means, and the third transport mechanism 54 corresponds to the third transport means.

In the heat treatment furnace 10 of the present embodiment described above, an inert gas is supplied from the gas supply device 22 to the furnace body 11 during the heat treatment, and the ambient gas of the furnace body 11 is heated to a temperature higher than that of the outside air. Therefore, when there is an ambient gas that flows out from the furnace body 11 through the opening 14 and flows to the first conveyance path 30 side, the ambient gas tends to stay in the upper space 63 provided on the vertical upper side of the first conveyance path 30. Thereby, the ambient gas is suppressed from flowing out to the outside through the first conveyance path 30. Further, the upper space 63 is likely to be in a state of being higher than the inside of the furnace body 11 by the retention of the environmental gas. Thereby, the force of the environmental gas flowing out from the inside of the furnace body 11 is pushed back to the inside of the furnace body 11, and the outflow of the ambient gas is suppressed. Further, the air suction device 77 sucks air into the lower space 73 provided on the lower side of the first transport path 30, and passes through the first transport path 30 from the upper space 63 (in the case where the carrier 95 is provided via the carrier plate) The gap between the left and right of 95) and the flow of gas to the space 73 below. Therefore, this flow acts as an air curtain, and the first conveyance path 30 between the outside and the inside of the furnace body 11 can suppress the outflow and the inflow of the gas. According to the above, the inflow of the outside air to the furnace body 11 or the outflow of the ambient gas to the outside can be sufficiently suppressed. Further, when the external air current is introduced, for example, oxygen, water, fine particles, and the like do not flow into the furnace body 11 and there is a case where the heat treatment is adversely affected. Therefore, it is required to suppress it. Moreover, the ambient gas inside the furnace body 11 is due to In order to contain, for example, an inert gas or a gas generated from the workpiece 96, it is not required to flow out to the outside. In the heat treatment furnace of the present invention, since the outflow and the inflow of the gas are suppressed, these requirements are easily satisfied.

Further, the heat treatment furnace 10 includes a second conveyance path 40 for conveying a conveyance path of the load-bearing plate 95 on which the workpiece 96 is placed between the first conveyance path 30 and the furnace body 11 The direction length L is 100 mm or more and 1000 mm or less. By setting the transport direction length L of the second transport path 40 to 100 mm or more, the outflow of the ambient gas from the furnace body 11 can be further suppressed.

Further, the heat treatment furnace 10 includes a third conveyance path 50 for conveying the carrier 95 on which the workpiece 96 is placed between the outside and the first conveyance path 30. At this time, by setting the minimum value Hmin of the gap height H described above to more than 0 mm and 50 mm or less, it is possible to further suppress the inflow of the outside air to the furnace body 11 or the outflow of the ambient gas to the outside. This is because the smaller the minimum value Hmin is, the more difficult it is for the gas to pass through in the third transport path 50 (the portion where the gap between the carrier plate 95 and the third transport path 50 in the height direction is small).

Further, by setting both the left gap width W _L and the right gap width W _R to 10 mm or more, the gap between the carrier plate 95 and the first conveyance path 30 in the left-right direction becomes sufficient, and the upper space 63 passes through the first conveyance path 30. The flow rate of the gas to the space below becomes larger. Therefore, the flow is easy to act as an air curtain, which can suppress the outflow and inflow of gas. In addition, by setting the left gap width W _L and the right gap width W _R to 150 mm or less, it is possible to prevent the gas from flowing in the direction (front-rear direction) along the conveyance path in the first conveyance path 30, so that the gas can be further suppressed. Outflow, inflow.

Moreover, the heat treatment furnace 10 includes a second transportation path 40 for use in The carrier plate 95 on which the workpiece 96 is placed is conveyed between the first conveyance path 30 and the furnace body 11; the second conveyance mechanism 44 has a plurality of second conveyance rollers 45 disposed on the second conveyance path 40, and The second conveyance roller 45 conveys the carrier plate 95 in a predetermined conveyance direction, and the flow suppression member 80 prevents the gas from flowing in the vertical direction between the second conveyance mechanisms 44 adjacent to each other in the conveyance direction. Therefore, when the ambient gas from the furnace body 11 passes through the second conveyance path 40, it is less likely to flow below the second conveyance roller 45, and the ambient gas from the furnace body 11 is easily guided to the upper space 63. Therefore, the outflow of the ambient gas to the outside can be more suppressed.

Further, the upper space forming portion 60 is formed in an upper space 63 inclined in a direction away from the furnace body 11 in the upper portion. When the ambient gas having a higher temperature than the outside air flows out of the furnace body 11, the flow direction of the ambient gas becomes the direction in which it rises away from the furnace body 11. Therefore, by the upper space 63 being inclined in the direction away from the furnace body 11, the ambient gas from the furnace body 11 is easily guided to the upper space 63, and the outflow to the outside can be further suppressed.

Further, the upper space forming portion 60 has the partition members 64a, 64b which are members which are inclined in the direction away from the furnace body 11 and divide the upper space 63 into the conveying direction of the carrier plate. A plurality of compartment spaces 65a to 65c. Therefore, the ambient gas from the furnace body 11 is easily guided to the upper space 63 by the plurality of compartment members 64a, 64b being inclined in the direction away from the furnace body 11 in the upper portion. Further, a plurality of compartment spaces 65a to 65c are connected to each other in the upper space 63 above. Therefore, when the ambient gas from the furnace body 11 flows to the first conveyance path 30, the ambient gas passes through any one of the plurality of compartment spaces 65a to 65c, and flows upward in the upper space 63, and then from the other After the compartment space flows, the flow back to the furnace is likely to occur. For example, moving from the first When the transport path 30 flows upward in the compartment spaces 65a and 65b, it passes through the upper space 63 and then flows downward in the compartment space 65c, and the flow to return to the furnace body 11 is liable to occur. Thereby, the effect of returning the ambient gas to the furnace body 11 and suppressing the outflow to the outside is improved.

Further, the lower space forming portion 70 is formed in a lower space 73 having a shape inclined in a direction in which the lower portion is close to the furnace body 11. When the external airflow reaches the first conveyance path 30, since the temperature of the ambient gas of the furnace body 11 is relatively high, the flow direction of the external air becomes the direction in which the furnace body 11 is lowered. Therefore, the lower space 73 is inclined in the lower direction toward the furnace body 11, and the outside air is easily guided to the lower space 73, and the inflow to the furnace body 11 can be further suppressed.

Further, the present invention is not limited to the above-described embodiments, and of course, it can be implemented in various forms as long as it falls within the technical scope of the present invention.

For example, in the above-described embodiment, the flow suppressing member 80 is disposed between the plurality of third transport rollers 55 or between the plurality of second transport rollers 45, but the present invention is not limited thereto. For example, instead of the flow suppressing member 80, the interval between the conveyance directions of the second conveyance rollers 45 may be made smaller than that of the first conveyance rollers 35. In this manner, as in the case of arranging the flow suppressing member 80, the gap gas between the second transport rollers 45 is hard to flow in the vertical direction. Therefore, similarly to the flow suppressing member 80, the effect of suppressing the outflow of the ambient gas to the outside can be obtained. Similarly, the third conveyance roller 55 may have a smaller interval in the conveyance direction than the first conveyance roller 35. Alternatively, instead of the flow suppressing member 80, a belt may be placed on the plurality of second transport rollers 45 as a belt transport belt for transporting the carrier 95. In this case, the gap gas between the second conveyance rollers 45 is hard to flow in the vertical direction by the presence of the belt. That is, the belt acts as a flow suppressing member. In this way, you can also get The effect of the outflow of the ambient gas to the outside is further suppressed. As for the third conveyance roller 55, a belt conveyor belt can be used in the same manner.

In the above-described embodiment, the first conveyance path 30, the second conveyance path 40, and the third conveyance path 50 are used as the load-bearing plate 95 and the workpiece 96 from the outside to the opening 14 of the furnace body 11, but Can be used as a move out. Further, in the above-described embodiment, the first conveyance path 30, the second conveyance path 40, the third conveyance path 50, the upper space forming portion 60, and the lower space forming portion 70 are included only on the opening 14 side, but may be employed. The same configuration as these members is also provided on the side of the opening 15 (a configuration that is symmetrical in the front-rear direction). In this way, it is also possible to suppress the outflow and inflow of the gas from the opening 15 and the outside.

In the above-described embodiment, the flow suppressing member 80 is supported by the two support posts 81. However, the support member may be supported by a plate-shaped support member that protrudes from the bottom of the second conveyance path 40 or the third conveyance path 50. For example, the flow-suppressing member 80 is supported by a support member having a plate shape along the upper and lower surfaces and the left and right surfaces, and the flow suppressing member 80 suppresses the flow of the gas in the vertical direction, and the support member can be suppressed by the plate-shaped support member. The flow of gas in the front and rear directions of the lower side of the second conveyance roller 45 or the third conveyance roller 55.

[Examples] [First Embodiment]

As the heat treatment furnace of the first embodiment, the test furnace 110 shown in Fig. 5 was produced. This test furnace 110 has the same configuration as the heat treatment furnace 10 of the above-described embodiment except that the heater 20 and the in-furnace conveyance roller 21 are not included in the furnace body 11, and the opening 15 is not provided. The size of the transfer port of the test furnace 110 is 30 mm in the vertical direction and 1270 mm in the left-right direction. In addition, the transport direction length L of the second transport path 40 is 200 mm, and the total length of the transport path lengths of the first transport path 30 and the third transport path 50 (=the length from the transport port 52 to the second transport path 40) is 500 mm. The size of the furnace body 11 is 300 mm in the vertical direction, 500 mm in the front-rear direction, and 1500 mm in the left-right direction. The inclination angle θ1 of the upper space forming portion 60 is set to 45°, and the inclination angle θ2 of the lower space forming portion 70 is set to 45°. The volume of the upper space forming portion 60 is 0.08 m ³ , and the volume of the lower space forming portion 70 is 0.04 m ³ .

In the test furnace 110, the test was carried out under the following conditions. First, in the first conveyance path 30, the second conveyance path 40, and the third conveyance path 50, four sheets are placed in the left-right direction without a gap, and three sheets of a total of twelve sheets are placed in the front-rear direction without gaps. . The total width of the four sheets in the left-right direction of the carrier sheet 95 is 1210 mm. Thereby, the left gap width W _L and the right gap width W _R are 30 mm in the entire first transport path 30. Further, the total length of the three sheets in the front and rear directions of the carrier plate 95 is 900 mm. The thickness of the upper and lower sides of the carrier plate 95 is 17 mm. Thereby, the minimum value Hmin is 13 mm (the opening height of the conveying port 52 is 30 mm - the thickness of the carrier plate 95 is 17 mm). In this state, the carrier plate 95 is not conveyed, the suction force of the air suction device 77 is set to 500 L/min, the temperature in the furnace body 11 is set to 80 ° C, and the supply amount of nitrogen gas from the gas supply device 22 is set to At 100 L/min, the oxygen concentration in the furnace body 11 after 1 to 2 hours and the leakage amount of nitrogen gas from the transfer port 52 to the outside were measured. Further, the oxygen concentration of the nitrogen gas supplied from the gas supply device 22 is set to 1 ppm or less. Further, during the test, the flow rate adjusting valve 26 is opened, and the exhaust valve 28 is fully closed, and only the circulation of the ambient gas by the outlet port 18 is performed, and the exhaust gas of the ambient gas from the exhaust port 19 is set. It is no state.

According to the same conditions as described above, only the thickness of the carrier plate 95 was changed, and a plurality of them were measured. Specifically, the thickness of the carrier plate 95 was set to 12 mm, 5 mm, 1 mm, and 0 mm (the carrier plate 95 was not disposed), and each was measured. Further, the minimum value Hmin of each case is 18 mm, 25 mm, 29 mm, and 30 mm.

As described above, the oxygen concentration of the furnace body 11 after the test of the case where the minimum value Hmin was set to 13 mm, 18 mm, 25 mm, 29 mm, and 30 mm was 15 ppm, 40 ppm, 421 ppm, 0.351%, and 1.42%. From this result, it is found that the smaller the minimum value Hmin, the lower the oxygen concentration is, and the inflow of the outside air is suppressed. Further, the amount of leakage of nitrogen to the outside was not detected in either case.

The present invention is based on Japanese Patent Application No. 2013-174886, filed on Jan. 26, 2013, which is hereby incorporated by reference.

[Industrial Applicability]

The present invention can be used in a heat treatment furnace for heat-treating a workpiece such as a process of baking a laminate which is a wafer of a ceramic capacitor.

10‧‧‧heat treatment furnace

11‧‧‧ furnace body

11a‧‧‧Handling space

12‧‧‧ front end

13‧‧‧ rear end face

14, 15‧‧‧ openings

16, 17‧‧‧ gas supply port

18‧‧‧Exit

19‧‧‧Exhaust port

0‧‧‧heater

21‧‧‧In-furnace conveying roller

22, 24‧‧‧ gas supply device

26‧‧‧Flow adjustment valve

28‧‧‧Exhaust valve

30‧‧‧1st way of transport

34‧‧‧1st transport mechanism

35‧‧‧1st conveying roller

40‧‧‧2nd transport route

44‧‧‧2nd transport mechanism

45‧‧‧2nd conveying roller

50‧‧‧3rd way of transport

52‧‧‧Transportation port

54‧‧‧3rd transport mechanism

55‧‧‧3rd carrying roller

60‧‧‧Top Space Formation Department

62‧‧‧ outer wall

63‧‧‧The space above

64a, 64b‧‧‧ compartment components

65a~65c‧‧‧ Compartment space

70‧‧‧The space formation department below

72‧‧‧ outer wall

73‧‧‧Lower space

74a, 74b‧‧‧ compartment components

75a~75c‧‧‧ Compartment space

76‧‧‧ suction port

77‧‧‧Aspirator

80‧‧‧Circulation suppression components

81‧‧‧ pillar

90‧‧‧ Controller

95‧‧‧Loading board

96‧‧‧Processed objects

110‧‧‧Test furnace

D1, D2‧‧ ‧ line segments

H‧‧‧ gap height

Hmin‧‧‧min

Θ1, θ2‧‧‧ angle

Claims (12)

A heat treatment furnace for heat-treating a workpiece to be placed on a carrier plate, comprising: a furnace body for internally heat-treating the object to be treated; and a first conveying path for externally and the furnace body The carrier plate on which the workpiece is placed is transported; the gas supply means supplies an inert gas as an ambient gas to the inside of the furnace body; and the heating means is such that the temperature of the ambient gas inside the furnace body is higher than that of the outside air The upper space forming portion is provided on the vertical side of the first conveyance path, and is formed in an upper space that opens only in the vertical lower side and communicates with the inside of the first conveyance path; the lower space forming portion is provided in the upper space. The lower side of the first conveyance path is formed in a lower space that is open on the vertical side and communicates with the inside of the first conveyance path, and a space suction means in the lower space that inhales the space below. The heat treatment furnace according to claim 1, wherein the second conveyance path is configured to convey the carrier plate on which the workpiece is placed between the first conveyance path and the furnace body. The conveyance path has a length L of 100 mm or more and 1000 mm or less in the conveyance direction. The heat treatment furnace according to claim 1 or 2, further comprising a third conveyance path for conveying the carrier plate on which the workpiece is placed between the outside and the first conveyance path When the carrier plate is transported on the third transport path, the gap height in the vertical direction of the carrier plate in the third transport path is the gap height H. The minimum value Hmin of the gap height H is more than 0 mm and 50 mm or less. The heat treatment furnace according to claim 1 or 2, wherein a direction perpendicular to the conveyance direction of the carrier sheet and parallel to the horizontal direction is a left-right direction, and when the carrier is transported by the first conveyance path, The size of the gap between the left end of the first conveyance path and the left-right direction of the carrier plate is the left gap width W _L , and when the carrier plate is transported by the first conveyance path, the right end of the first conveyance path is When the size of the gap in the left-right direction of the carrier plate is the right gap width W _R , the left gap width W _L and the right gap width W _R are both in the range of 10 mm or more and 150 mm or less. The heat treatment furnace according to claim 1 or 2, further comprising: a second conveyance path for conveying the carrier plate on which the workpiece is placed between the first conveyance path and the furnace body; (2) The transport means includes a plurality of second transport rollers disposed in the second transport path, and the carrier plate is transported in a predetermined transport direction by the second transport roller; and the flow suppressing member is adjacent to the transport direction The gap between the second conveyance rollers suppresses the gas from flowing in the vertical direction. The heat treatment furnace according to claim 1 or 2, further comprising: a second conveyance path for conveying the carrier plate on which the workpiece is placed between the first conveyance path and the furnace body; (1) The transport means includes a plurality of first transport rollers disposed in the first transport path, and the carrier is transported in a predetermined transport direction by the first transport roller; and the second transport means has a first transport roller Smaller spacing of the transport rollers The plurality of second conveyance rollers of the second conveyance path are conveyed by the second conveyance roller in the conveyance direction. The heat treatment furnace according to claim 1 or 2, wherein the third conveyance path is configured to convey the carrier sheet on which the workpiece is placed between the outside and the first conveyance path; and the third conveyance The means includes a plurality of third transport rollers disposed on the third transport path, and the carrier plate is transported in a predetermined transport direction by the third transport roller; and the flow suppressing member is adjacent to the third transporting direction The gap between the conveyance rollers suppresses the gas from flowing in the vertical direction. The heat treatment furnace according to claim 1 or 2, wherein the third conveyance path is configured to convey the carrier sheet on which the workpiece is placed between the outside and the first conveyance path; the first conveyance The method includes a plurality of first conveyance rollers disposed on the first conveyance path, and the carrier sheet is conveyed in a predetermined conveyance direction by the first conveyance roller; and the third conveyance means has a ratio of the first conveyance roller The plurality of third transport rollers disposed on the third transport path are disposed at a smaller interval, and the carrier plate is transported in the transport direction by the third transport roller. The heat treatment furnace according to claim 1 or 2, wherein the upper space forming portion forms the upper space inclined in a direction away from the furnace body. The heat treatment furnace of claim 9, wherein the upper space forming portion has a partition member which is located at an upper portion away from the furnace body The inclined space is divided into a plurality of compartment spaces along the carrying direction of the carrier. The heat treatment furnace of claim 10, wherein the plurality of compartment spaces are in communication with each other in the upper space. A heat treatment furnace according to claim 1 or 2, wherein the lower space forming portion is formed in the lower space inclined in a direction in which the lower portion is close to the furnace body.