JP3602604B2 - Mesh belt conveyor type atmosphere furnace - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to an atmosphere furnace in which a lid on which processed products are loaded is conveyed in a furnace by a mesh belt conveyor, and the processed products are subjected to atmosphere brazing and atmospheric heat treatment in a furnace chamber.
[0002]
[Prior art]
In an atmosphere furnace of this type, a rider loaded with a processed product is continuously loaded into the furnace chamber at small intervals in front and rear. For this reason, it is not possible to provide a partition door that opens and closes each time the lid passes, and when the processing material becomes large, a large amount of atmospheric gas is introduced into the furnace chamber to prevent oxidation of the processing material due to the inflow of outside air from the entrance and exit of the furnace. It had to be sent and was uneconomical.
[0003]
[Problems to be solved by the invention]
An object of the present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to provide a mesh belt conveyor type atmosphere furnace capable of reducing the amount of atmosphere gas used.
[0004]
[Means for Solving the Problems]
The mesh belt conveyor type atmosphere furnace of the present invention is a mesh belt conveyor type atmosphere furnace in which a rider loaded with a processed product is conveyed in the furnace by the mesh belt conveyor. An inlet throat and an outlet throat at least twice as long are provided, and at least one of a front part and a rear part of the rider, an upper edge and a left and right edge face the inner wall surface of each throat with a gap. It is characterized in that the partition wall is erected and fixed.
[0005]
Further, if an intermediate door is provided at at least one of the position of the entrance throat near the furnace chamber and the position of the exit throat near the furnace chamber, when the rider group starts loading into the entrance throat or from the exit throat, This is particularly preferable because it is possible to prevent outside air from entering the furnace at the end of the delivery.
[0006]
[Action]
In the mesh belt conveyor type atmosphere furnace according to the present invention, when the rider loaded with the processed product passes through the entrance throat and the exit throat, the partition standing upright on the rider is a throat furnace as a movable partition wall. The throat having an opening area that communicates with the outside to a small area and having a length equal to or more than twice the length of the rider has at least one sheet during passage through the rider (at least two sheets when the rider interval = 0). The above partition wall is always present, so that a small amount of atmosphere gas is required to prevent outside air from entering the furnace chamber from outside the furnace via the throat section.
[0007]
Also, if an intermediate door is provided at a position near the furnace chamber of the entrance side throat, when the lidar group starts to enter the furnace interior (at the start of processing of one lot of the processing material group), the first lidar reaches the position near the intermediate door, and By closing the intermediate door until the partitioning action by the partition is obtained, outside air can enter the furnace from the inlet throat inlet when the inlet door is opened at the start of the furnace interior (at the time of loading the leading lid). Can be prevented.
[0008]
In addition, if an intermediate door is provided at a position near the furnace chamber of the exit side throat, the rearmost rider has passed the intermediate door position at the end of the out-of-furnace delivery of the lidar group (at the end of processing of one lot of processed product group). By closing the intermediate door at the time, it is possible to prevent outside air from entering the furnace from the outlet throat outlet before closing the outlet door at the end of the out-of-furnace delivery (at the time of sending out the last lidar).
[0009]
【Example】
An embodiment of the present invention will be described below with reference to FIGS. In the figure, reference numeral 1 denotes an atmosphere brazing furnace having a mesh belt conveyor 2, a furnace chamber 5 comprising a heating chamber 3 and a cooling chamber 4, and a processing material 6 comprising a base material and a brazing material (see FIG. 2). ) Is loaded on a rider 7, a brazing material is melted in the heating chamber 3 during the transfer in the furnace, and a brazing process is performed in the cooling chamber 4 to join the brazing material to the base material. The heating chamber 3 is provided with a heating element such as an electric heater, and the cooling chamber 4 is provided with a means for blowing cold air. These are known and are not shown. The illustration of the support means of the mesh belt 2a of the mesh belt conveyor 2 inside the heating chamber 3 and outside the furnace, and the illustration of the processing material 6 in FIG. 1 are also omitted for simplification.
[0010]
Reference numeral 11 denotes an inlet throat provided continuously with the inlet 3a of the heating chamber 3, and its length X is set to be at least twice the length L of the rider 7. Reference numeral 12 denotes an entrance door at an entrance 13 of the entrance throat 11. Reference numeral 16 denotes an outlet throat connected to the outlet 4a side of the cooling chamber 4, and its length Y is at least twice the length L of the rider 7. Reference numeral 17 denotes an exit door at an exit 18 of the exit throat 16. The entrance door 12 and the exit door 17 are opened and closed by a known opening and closing drive device such as a pneumatic cylinder or a motor. When the doors are closed, each door is moved to a position where the lower edge thereof faces the mesh belt 2a with a small clearance. Is driven downward.
[0011]
On the other hand, as shown in FIG. 3, the rider 7 has a front end portion (advancing portion) of a processing material support 8 formed of a pallet-like body having air permeability (in this embodiment, a bent steel sheet having a large number of holes punched out on the bottom surface). A partition wall 9 formed by bending a steel plate and providing a brim portion for reinforcement at the edge portion is fixedly attached to the side end portion) by bolts 10 in a screen-like manner. As shown in FIG. 2, the front shape of the partition 9 is such that a small amount of clearance G is formed between the inner wall surface of the entrance throat 11 and the upper edge 9a and the left and right edges 9b of the partition 9. It has an outer shape and dimensions close to the cross-sectional shape of the inner wall surface (therefore, the shape of the inlet 13). The inner wall surface of the outlet throat 16 (therefore, the outlet 18) has the same cross-sectional shape as the inlet throat 11.
[0012]
The clearance G is determined by the finishing accuracy of the wall surfaces of the entrance-side throat 11 and the exit-side throat 16, the dimensional accuracy of the partition wall 9, the variation of the rider mounting position on the mesh belt 2 a, and the displacement of the rider 7 when moving with the mesh belt 2 a. In consideration of vertical and horizontal movements, it is desirable that the partition 9 be as small as possible within a range where it does not contact the inner wall surface of each throat. Depending on the cross-sectional dimensions of the inner wall surface, it is preferably about 20 to 30 mm. . In this embodiment (height H = 380 mm, h = 370 mm, width W = 490 mm in FIG. 2), the clearance G was set to 20 mm.
[0013]
In the atmosphere brazing furnace 1 having the above-described configuration, the processing material 6 is loaded on the rider 7 having the above-described partition wall 9 and is subjected to atmosphere brazing while being conveyed in the furnace by the mesh belt conveyor 2. At this time, at least one rider 7 and therefore at least one partition wall 9 are present in the inlet throat 11 and the outlet throat 16 unless the gap between the riders 7 is too large. The area of the opening communicating with the outside is narrowed by the partition wall 9 and is an area corresponding to a clearance G between the partition wall 9 and the inner wall surface of each throat portion (specifically, a clearance corresponding to the thickness of the mesh belt is added thereto). The inside and outside will communicate.
[0014]
The opening area of the gap G is sufficiently smaller than the area of the inlet 13 and the outlet 18 of each throat, that is, the area of the inlet 3a of the heating chamber 3 and the area of the outlet 4a of the cooling chamber 4. The amount of atmospheric gas supplied into the furnace chamber 5 to prevent outside air from entering the furnace may be small, and the reduced small amount of effluent gas reliably prevents outside air from entering the furnace from outside the furnace. Because
[0015]
In the furnace of this embodiment (the length L of the lid 7 is 600 mm, the width S is 450 mm, the length of the throat portion X is 3000 mm, Y is 2400 mm, the inner wall surface shape of the throat portion and the clearance G are as described above). Compared to the case of using a conventional lidar having only the processing material support 8 having no partition wall 9, the amount of use of the atmospheric gas (the endothermic gas in this embodiment) could be reduced to about 1/5.
[0016]
Next, another embodiment of the present invention will be described with reference to FIGS. In the drawing, reference numeral 21 denotes an entrance intermediate door provided at a position of the entrance throat 11 near the heating chamber 3, and reference numeral 22 denotes an exit intermediate door provided at a position of the exit throat 16 near the cooling chamber 4. The intermediate door is driven down to a position where the lower edge thereof faces the mesh belt 2a with a small clearance when the intermediate door is closed. The other configuration is the same as that of the above-described embodiment, and the same portions are denoted by the same reference numerals, and detailed description thereof is omitted. In FIG. 4, the illustration of the processing material 6 is omitted.
[0017]
In the atmosphere brazing furnace 20 of this embodiment, the outside air is prevented from entering the furnace at the start of the inside of the lidar group into the furnace interior and at the end of the delivery outside the furnace, that is, at the start and end of the processing of the processing material group of one lot. First, the operation at the time of loading the rider is as shown in FIG. That is, the entrance door 12 and the intermediate door 21 are closed until the group of riders reaches the entrance 13 of the entrance-side throat 11, and when the first rider 7 loaded with the processing material 6 reaches the vicinity of the entrance door 12. Then, the entrance door 12 is opened as shown in FIG. Then, when the leading rider 7 reaches the vicinity of the intermediate door 21, the intermediate door 21 is opened as shown in FIG.
[0018]
By closing the intermediate door 21 when the entrance door 12 is opened as described above, the inside of the furnace chamber 5 and the outside of the furnace are in communication with each other over the entire area of the entrance 13, and the outside air outside the furnace enters the furnace chamber 5. The outside air that has entered the entrance side of the intermediate door 21 is returned to the outside of the furnace together with the atmospheric gas from inside the furnace chamber 5 after opening the intermediate door 21. 5 (c) with both doors open, the rider charging is continued. After the last rider 7 of the rider group passes through the entrance 13, the entrance door 12 is closed as shown in FIG. 5 (d). If the intermediate door 21 is closed after passing through the intermediate door position, the amount of atmospheric gas released from the entrance throat 11 can be further reduced by closing the double door.
[0019]
When sending the processed lidar group, the exit door 17 and the intermediate door 22 of the outlet throat 16 are closed as shown in FIG. When reaching the vicinity of 22, the intermediate door 22 is opened. Next, when the leading rider 7 reaches the vicinity of the exit door 17, the exit door 17 is opened as shown in FIG. 6 (c) with both doors open, the rider continues to be sent out. When the last rider 7 has passed the position of the intermediate door 22, the intermediate door 22 is closed as shown in FIG. After passing through the exit door 17 position, the exit door 17 is closed.
[0020]
In this way, when the last rider 7 is discharged from the outlet 18 or after the partition 9 of the rider 7 passes through the outlet 18, the intermediate door 22 is closed even if the exit door 17 is open. Therefore, the inside of the furnace chamber 5 and the outside of the furnace are in communication with each other over the entire area of the outlet 18, so that outside air outside the furnace can be prevented from entering the furnace chamber 5. After the exit door 17 is closed, the amount of atmospheric gas released from the outlet throat 16 can be further reduced by closing the double door.
[0021]
The present invention is not limited to the above embodiments. For example, the specific structure of the rider 7 may be other than that described above, and the partition 9 may be provided at both the front and rear portions of the rider. In this case, an increase in the number of partition walls can prevent the outside air from entering the furnace with a smaller amount of atmospheric gas. Further, an intermediate door may be provided on only one of the entrance-side throat 11 and the exit-side throat 16.
[0022]
The present invention can be widely applied to various mesh belt conveyor type atmosphere furnaces such as an atmosphere brazing furnace and an atmosphere heat treatment furnace.
[0023]
【The invention's effect】
As described above, according to the present invention, the opening area of the entrance throat and the exit throat communicating with the outside of the furnace is reduced to a small area by the partition wall vertically fixed to the rider. Only a small amount of atmosphere gas is required to prevent outside air from entering the furnace through the furnace.
[0024]
Further, according to the second aspect of the present invention, the opening and closing operation of the intermediate door prevents the outside air from entering the furnace at the time of starting the loading of the rider group into the entrance throat and / or at the end of the delivery from the exit throat. Can be prevented.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of a mesh belt conveyor type atmosphere brazing furnace according to an embodiment of the present invention, in which an intermediate portion is partially omitted.
FIG. 2 is a sectional view taken along line AA of FIG.
FIG. 3 is a perspective view of the rider shown in FIG. 1;
FIG. 4 is a longitudinal sectional view of a mesh belt conveyor type atmosphere brazing furnace according to another embodiment of the present invention, in which an intermediate portion is partially omitted.
5 is a view (longitudinal sectional view) for explaining a rider charging operation in an inlet throat section of the furnace of FIG.
6 is a view (longitudinal sectional view) for explaining a rider delivery operation in an outlet throat section of the furnace of FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Atmosphere brazing furnace, 2 ... Mesh belt conveyor, 3 ... Heating room, 4 ... Cooling room, 5 ... Furnace room, 6 ... Processing material, 7 ... Rider, 8 ... Processing material support, 9 ... Partition wall, 11 ... Inlet throat, 12 entrance door, 13 entrance, 16 exit throat, 17 exit door, 18 exit, 20 atmosphere brazing furnace, 21 intermediate door, 22 intermediate door.

Claims (2)

In a mesh belt conveyor type atmosphere furnace in which a rider loaded with processed products is conveyed in a furnace by a mesh belt conveyor, an inlet throat having a length at least twice as long as the length of the rider is provided at an inlet side and an outlet side of a furnace chamber. And a protruding side throat, wherein at least one of the front part and the rear part of the rider is provided with a partition wall in which an upper edge part and a right and left side edge part are opposed to the inner wall surface of each throat with a clearance. Mesh belt conveyor type atmosphere furnace. 2. The mesh belt conveyor type atmosphere furnace according to claim 1, wherein an intermediate door is provided in at least one of a position of the inlet side throat near the furnace chamber and a position of the outlet side throat near the furnace chamber.

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