JP2013031862A - Non-flux brazing furnace for aluminum product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve brazing quality without using flux and to reduce a running cost by: providing a structure of keeping an inert atmosphere of high purity inside a furnace with argon gas; and attaining the reuse of argon gas while recovering it.SOLUTION: A brazing chamber 4 and a cooling chamber 5 are filled with argon gas, and a part of the argon gas is supplied to a recovery tank 10. When an aluminum product to be brazed is carried into the brazing chamber 4 and when the brazed aluminum product is carried out of the cooling chamber 5, air in a carry-in vacuum purge chamber 2 and a carry-out vacuum purge chamber 7 is exhausted and replaced with argon gas in the recovery tank 10. The pressure of the brazing chamber 4 and cooling chamber 5 which are filled with argon gas is set higher than that of the carry-in vacuum purge chamber 2 and carry-out vacuum purge chamber 7 which are filled with argon gas.

Description

  The present invention relates to a brazing furnace for aluminum products, and more particularly to a non-flux brazing furnace for aluminum products capable of brazing aluminum products without using flux.

  It is important that the furnace for brazing the metal prevents oxidation of the surfaces of the joined parts. The brazing of the stainless steel product is performed in a vacuum atmosphere or a hydrogen atmosphere at a brazing temperature of about 1000 ° C. to 1200 ° C., and is easily reduced. Therefore, oxidation of the surface of the joining component is not a problem.

  However, in a brazing furnace for aluminum products, brazing is performed at a temperature of about 600 ° C., and aluminum is a difficult-to-reduced metal and is difficult to reduce. Therefore, conventionally, a flux is used to prevent the oxidation of the surface of the joining component, to remove the oxide film on the surface, and to improve the flow of the low.

  Further, an inert gas (nitrogen gas, argon gas) is used as the furnace atmosphere to suppress the oxidation of the surface of the joining component and the oxidation of the flux. In addition, some or all of the furnace inner wall, muffle, heat insulating material, etc. are made of carbonaceous material such as graphite. Thereby, even if air and oxygen exist as disturbances, they contact and react as carbonaceous matter so as to keep the oxygen concentration of the atmosphere gas in the furnace low (see Patent Documents 1, 2, 3, and 4).

Japanese Patent Laid-Open No. 10-5993 Japanese Patent Laid-Open No. 11-83332 JP 2004-50223 A JP 2007-319924 A

  Nitrogen gas in a conventional inert gas atmosphere is not necessarily preferable because the surface of the joining component is easily nitrided and brazing performance is deteriorated. Therefore, in order to maintain an inert gas atmosphere, it is preferable to use an inert gas as an argon gas.

  However, since the cost of argon gas is high, if argon gas is used to maintain an inert gas atmosphere, the operating cost increases. Therefore, if the used argon gas can be recovered and reused, not only the operating cost can be reduced, but also the effective use of resources can be promoted.

  However, even if the argon gas used in the brazing furnace is recovered or excess flux is mixed as an impurity and reused, the proper inert atmosphere cannot be maintained and the brazing quality deteriorates. Will be allowed to.

The present invention aims to solve the above-described conventional problems, and has the following main points.
(1) An aluminum product brazing furnace capable of maintaining a high purity inert atmosphere and low oxygen atmosphere with argon gas without using a flux is realized.

(2) By adopting such a configuration, the argon gas can be reused while being recovered, and the brazing quality is improved in a low oxygen atmosphere.
(3) In addition, the running cost for the brazing process is reduced by the recovery and use of argon gas and the non-use of flux (non-flux).

  In order to solve the above-described problems, the present invention provides a carry-in vacuum purge chamber, a brazing chamber, a cooling chamber, a carry-out vacuum purge chamber, a conveyance belt device or a conveyance roller hearth device provided through the brazing chamber and the cooling chamber. A brazing furnace for an aluminum product comprising: a brazing chamber and a cooling chamber filled with argon gas; and a part of the argon gas can be supplied to the recovery tank; Supply to the carry-in vacuum purge chamber and the carry-out vacuum purge chamber and allow recovery from the carry-in vacuum purge chamber and the carry-out vacuum purge chamber, and when the brazed aluminum product is carried into the brazing chamber and the brazed aluminum product is cooled When unloading from the tank, the air in the carry-in vacuum purge chamber and the carry-out vacuum purge chamber is evacuated and can be filled with argon gas in the recovery tank The pressure in the brazing chamber and the cooling chamber filled with argon gas is configured to be higher than that of the carry-in vacuum purge chamber and the carry-out vacuum purge chamber filled with argon gas, without using flux. Provided is a brazing furnace for aluminum products, which is capable of brazing aluminum products.

  In order to solve the above-described problems, the present invention provides a carry-in vacuum purge chamber, a brazing chamber, a cooling chamber, a carry-out vacuum purge chamber, a conveyance belt device or a conveyance roller hearth device provided through the brazing chamber and the cooling chamber. A brazing furnace for an aluminum product comprising an argon gas piping system, an argon gas recovery tank, and an air exhaust system, wherein the brazing chamber is surrounded by a heat insulating material. The furnace chamber has a graphite muffle extending in the longitudinal direction of the furnace chamber, and a plurality of radiant tube heaters or silicon carbide heaters installed outside the muffle, and a belt or a transport roller hearth of the transport belt device The roller of the device is made of heat-resistant steel or carbon fiber reinforced carbon composite material, and the conveyor part of the conveyor belt device or conveyor roller hearth device passes through the muffle The argon gas piping system fills the brazing chamber and the cooling chamber with argon gas, supplies a part of the argon gas to the recovery tank, and supplies the recovery tank argon gas into the carry-in vacuum purge chamber and the carry-out vacuum purge. Supply to the chamber and recovery from the carry-in vacuum purge chamber and the carry-out vacuum purge chamber, and carry-in vacuum purge when carrying the brazed aluminum product into the brazing chamber and when carrying out the brazed aluminum product from the cooling chamber The air in the chamber and the discharge vacuum purge chamber is evacuated and filled with argon gas supplied from the recovery tank, and the pressure in the brazing chamber and cooling chamber filled with argon gas is the vacuum loaded with argon gas. It is configured to be higher than the chamber and the carry-out vacuum purge chamber, and aluminum is used without using flux. Providing brazing furnace of the aluminum product, characterized in that to enable brazing of the product.

  The argon gas piping system includes an argon gas source supply pipe that supplies argon gas to the brazing chamber, an argon gas supply pipe that supplies argon gas from the brazing chamber and the cooling chamber to the argon gas recovery tank, and collects the argon gas The argon gas sucked by the vacuum pump for argon gas is recovered to the recovery tank from the purge feed argon gas supply pipe supplied from the tank to the carry-in vacuum purge chamber and the carry-out vacuum purge chamber, and the carry-in vacuum purge chamber and the carry-out vacuum purge chamber It is preferable that the air exhaust system includes an air exhaust pipe that exhausts air sucked from the carry-in vacuum purge chamber and the carry-out vacuum purge chamber by the air vacuum pump, respectively.

  The carry-in vacuum purge chamber and the carry-out vacuum purge chamber each have an entrance door and an exit door that can be opened and closed independently, and when the aluminum product to be brazed is carried into the brazing chamber and from the cooling chamber When carrying out, the carry-in vacuum purge chamber and the carry-out vacuum purge chamber are closed by closing the entrance door and the exit door, respectively, and after being evacuated, filled with argon gas, and then the exit door of the carry-in vacuum purge chamber It is preferable that the entrance door of the carry-out vacuum purge chamber is opened.

  A front chamber is integrally provided at the front of the brazing chamber, a rear chamber is integrally provided at the rear of the cooling chamber, and belt pulleys before and after the conveyor belt device are provided in the front chamber and the rear chamber. It is preferable that the rollers of the transport roller hearth device that are arranged or that are provided in either the front chamber or the rear chamber are driven by a roller driving device.

  According to the present invention, since a high purity inert atmosphere is maintained in the furnace with argon gas without using a flux, it can be reused while collecting argon gas, and in a low oxygen atmosphere, The brazing quality can be improved, and the running cost for the brazing process can be reduced due to the use of argon gas and the non-use of flux (non-flux).

It is a figure explaining Example 1 of the brazing furnace of the aluminum product which concerns on this invention. It is a figure explaining the control apparatus of Example 1. FIG. It is a figure explaining Example 2 of the brazing furnace of the aluminum product which concerns on this invention.

  The form for implementing the brazing furnace of the aluminum product which concerns on this invention is demonstrated below with reference to drawings based on an Example.

  In a brazing furnace for aluminum products, it is necessary to keep the atmosphere in the furnace in a low oxygen atmosphere. A feature of the brazing furnace for aluminum products of the present invention is that a high purity inert atmosphere is maintained in the furnace with argon gas without using a flux, and the argon gas is recovered and reused while collecting less argon. It is a configuration that can maintain a low oxygen atmosphere in the furnace with the amount of gas used, improve brazing quality, and reduce running costs.

  Furthermore, in the brazing furnace for aluminum products of the present invention, a muffle or the like is configured using a non-oxidizing material in order to keep the inside of the furnace in a low oxygen atmosphere.

  Embodiment 1 of the brazing furnace for aluminum products of the present invention will be described below with reference to FIG. FIG. 1 is a diagram showing an overall configuration of an aluminum product brazing furnace 1 according to a first embodiment of the present invention. The brazing furnace 1 for aluminum products is generally composed of a carry-in vacuum purge chamber 2, a front chamber 3, a brazing chamber 4, a cooling chamber 5, a rear chamber 6, a carry-out vacuum purge chamber 7, a transport belt device 8, and an argon gas. The piping system 9, the recovery tank 10, and the air exhaust system 11 are provided.

  An inlet table 16 is provided in front of the carry-in vacuum purge chamber 2 of the brazing furnace 1 for aluminum products, and an outlet table 17 is provided behind the carry-out vacuum purge chamber 7. The inlet table 16 is a means for feeding the aluminum product to be brazed into the carry-in vacuum purge chamber 2, and the outlet table 17 is brazed and carried out from the cooling chamber 5, and the aluminum product fed out from the carry-out vacuum purge chamber 7 It is a means to accept.

  In the brazing chamber 4, a tunnel-shaped furnace chamber 21 is formed on the furnace inner wall 20, and the outside of the furnace inner wall 20 is surrounded by a heat insulating material 22.

  A muffle 26 is disposed at the center of the brazing chamber 4 so as to extend in the longitudinal direction (front-rear direction) from the entrance to the exit of the brazing chamber 4. The muffle 26 is made of graphite, and constitutes a heating passage 28 and functions as an oxygen getter material, atmosphere holding, and heat insulating plate.

  A plurality of heaters 27 are arranged above and below the muffle 26 at intervals in the longitudinal direction. As the plurality of heaters 27, rod-shaped silicon carbide heaters (also referred to as “silicon carbide heaters”) 27 are used, and are respectively attached horizontally to the longitudinal direction of the brazing chamber 4. The heater 27 heats the inside of the heating passage 28 constituted by the muffle 26 so as to be about 600 ° C. The plurality of heaters 27 may be a plurality of radiant tube heaters instead of the silicon carbide heater.

  The conveyor belt device 8 includes a conveyor belt 31, a belt driving device 32, and a belt pulley 33. A C / C transport belt 31 is disposed through the front chamber 3, the brazing chamber 4, the cooling chamber 5, and the rear chamber 6. Here, “made by C / C” means that it is made of a carbon fiber reinforced carbon composite material (referred to as “C / C composite”).

  The front chamber 3 is provided integrally with the brazing chamber 4 at the front portion of the brazing chamber 4, and the rear chamber 6 is provided integrally with the cooling chamber 5 at the rear portion of the cooling chamber 5. In the front chamber 3 and the rear chamber 6, belt pulleys 33 before and after the conveyor belt 31 are installed.

  The conveyor belt 31 is provided so as to pass through the heating passage 28 surrounded by the muffle 26 in the brazing chamber 4. Thereby, the aluminum product to be brazed is transported by the transport belt 31 and passes through the heating passage 28.

  An inlet door 35 and an outlet door 36 that can be opened and closed independently are provided on the inlet side and the outlet side of the carry-in vacuum purge chamber 2. When the entrance door 35 and the exit door 36 are simultaneously closed, the carry-in vacuum purge chamber 2 is sealed.

  Similarly, an inlet door 39 and an outlet door 40 that can be opened and closed independently are provided on the inlet side and the outlet side of the carry-out vacuum purge chamber 7, respectively. When the entrance door 39 and the exit door 40 are simultaneously closed, the carry-out vacuum purge chamber 7 is sealed.

The argon gas piping system 9 includes the following piping and the like.
(1) An argon gas source supply pipe 47 that supplies argon gas from its supply source 45 to the brazing chamber 4 by a supply source pump 46.
(2) Argon gas supply pipe 50 for supplying argon gas from brazing chamber 4 and cooling chamber 5 to recovery tank 10. A supply pump 51 is provided in the middle of the argon gas supply pipe 50.
(3) A purge feed argon gas supply pipe 55 that pressurizes argon gas from the recovery tank 10 by the purge feed pump 54 and supplies the argon gas to the carry-out vacuum purge chamber 7 and the carry-out vacuum purge chamber 7.
(4) An argon gas recovery pipe 59 that recovers the argon gas sucked by the argon gas vacuum pump 58 from the carry-in vacuum purge chamber 2 and the carry-out vacuum purge chamber 7 to the recovery tank 10.
(5) An argon gas exhaust pipe 62 that exhausts excess argon gas from the recovery tank 10.

  The air exhaust system 11 includes an air exhaust pipe 64 that exhausts air from the carry-in vacuum purge chamber 2 and the carry-out vacuum purge chamber 7 by the air vacuum pump 63.

  Argon gas is supplied from the supply source 45 to the brazing chamber 4 through the argon gas source supply pipe 47 by the supply pump 46. In this case, the pressures in the furnace pressure sensor 70 and the cooling chamber pressure sensor 71 are detected to control the supply source pump 46 so that the pressures in the brazing chamber 4 and the cooling chamber 5 are always kept at atmospheric pressure or higher.

  A part of the argon gas is supplied from the brazing chamber 4 and the cooling chamber 5 to the recovery tank 10 through the argon gas supply pipe 50.

  Argon gas is supplied from the recovery tank 10 to the carry-in vacuum purge chamber 2 and the carry-out vacuum purge chamber 7 through a purge feed argon gas supply pipe 55. The pressure in the brazing chamber 4 and the cooling chamber 5 filled with argon gas is set to be higher than the pressure in the carry-in vacuum purge chamber 2 and the carry-out vacuum purge chamber 7 filled with argon gas.

  Specifically, the pressures in the brazing chamber 4, the cooling chamber 5, the carry-in vacuum purge chamber 2 and the carry-out vacuum purge chamber 7 are respectively set to the furnace pressure sensor 70, the cooling chamber pressure sensor 71, the carry-in vacuum purge chamber pressure sensor 72, As shown in FIG. 2, the supply pump 46, the purge feed pump 54, the argon gas are detected by the control device 75 (a microcomputer or the like is used) based on the detection by the discharge vacuum purge chamber pressure sensor 73. The operation of the vacuum pump 58 is controlled. Thereby, the pressures of the brazing 4, the cooling chamber 5, the carry-in vacuum purge chamber 2, and the carry-out vacuum purge chamber 7 are controlled.

  An argon gas exhaust pipe 62 for exhausting surplus argon gas when the argon gas in the recovery tank 10 exceeds its storage capacity is connected to the recovery tank 10.

  Note that atmospheric return pressure pipes 76 and 77 are attached to the carry-in vacuum purge chamber 2 and the carry-out vacuum purge chamber 7 so as to communicate with each other.

(Function)
The operation of the brazing furnace 1 for an aluminum product according to the present invention having the above configuration will be described. Before starting the brazing operation, as a preparatory operation, the carry-in vacuum purge chamber 2 closes at least its outlet door 36, the carry-out vacuum purge chamber 7 closes at least the inlet door 39, and seals the brazing chamber 4 and the cooling chamber 5. State.

  Then, argon gas is supplied from the supply source 45 to the brazing chamber 4 through the argon gas source supply pipe 47 by the supply source pump 46. Further, a part of the argon gas is supplied from the brazing chamber 4 and the cooling chamber 5 to the recovery tank 10 by the supply pump 51.

  After the above preparatory work is completed, the brazing work of the aluminum product is performed in the next process. With the outlet door 36 of the carry-in vacuum purge chamber 2 and the inlet door 39 of the carry-out vacuum purge chamber 7 closed, the inlet door 35 is opened and the aluminum product to be brazed is transferred from the inlet table 16 into the carry-in vacuum purge chamber 2. Load it.

  Then, the inlet door 35 of the carry-in vacuum purge chamber 2 and the outlet door 40 of the carry-out vacuum purge chamber 7 are closed, and the carry-in vacuum purge chamber 2 and the carry-out vacuum purge chamber 7 are sealed. In this state, the air vacuum pump 63 is operated to evacuate the air in the carry-in vacuum purge chamber 2 and the carry-out vacuum purge chamber 7 to bring the carry-in vacuum purge chamber 2 and the carry-out vacuum purge chamber 7 into a vacuum state.

  Next, the purge feed pump 54 is operated to supply argon gas from the recovery tank 10 to the carry-in vacuum purge chamber 2 and the carry-out vacuum purge chamber 7 through the purge feed argon gas supply pipe 55. In this case, the pressure in the brazing chamber 4 and the cooling chamber 5 filled with argon gas is set to be higher than the pressure in the carry-in vacuum purge chamber 2 and the carry-out vacuum purge chamber 7 filled with argon gas.

  Next, the outlet door 36 is opened in a state where the inlet door 35 of the carry-in vacuum purge chamber 2 is closed, and an aluminum product to be brazed from the carry-in vacuum purge chamber 2 is placed on the transport belt 31, and the transport belt 31 moves forward. It is carried into the brazing chamber 4 from the chamber 3.

  Since the pressure in the brazing chamber 4 and the cooling chamber 5 is set higher than the pressure in the carry-in vacuum purge chamber 2 filled with argon gas, the carry-in vacuum purge is performed even if the outlet door 36 of the carry-in vacuum purge chamber 2 is opened. Argon gas does not flow into the brazing chamber 4 from the chamber 2.

  Therefore, even if the air is not sufficiently exhausted from the carry-in vacuum purge chamber 2, the air does not enter the brazing chamber 4 when the outlet door 36 of the carry-in vacuum purge chamber 2 is opened. Therefore, the brazing chamber 4 and the cooling chamber 5 can be maintained in a low oxygen atmosphere.

  After the aluminum product to be brazed is carried into the brazing chamber 4, the exit door 36 is closed. At the stage where all the brazing operations for the aluminum product are completed, the pressure is returned to the atmosphere by the atmospheric pressure return pipe 76, and then the inlet door 35 of the carry-in vacuum purge chamber 2 is opened.

  The aluminum product to be brazed carried into the brazing chamber 4 is transported through the muffle 26 by the transport belt 31, heated at around 600 ° C., and brazed. The brazed aluminum product is transported to the cooling chamber 5 by the transport belt 31 and cooled.

  Next, the inlet door 39 of the unloading vacuum purge chamber 7 is opened, and the brazed aluminum product is unloaded from the rear chamber 6 to the unloading vacuum purge chamber 7. In this case, since the pressure in the cooling chamber 5 is set higher than the pressure in the carry-out vacuum purge chamber 7 filled with argon gas, even if the inlet door 39 of the carry-out vacuum purge chamber 7 is opened, the carry-out vacuum purge chamber 7. Therefore, argon gas does not flow into the brazing chamber 4 and the cooling chamber 5 from the inside.

  Therefore, even if the air is not sufficiently exhausted from the carry-out vacuum purge chamber 7, the air enters the brazing chamber 4 and the cooling chamber 5 when the entrance door 39 of the carry-out vacuum purge chamber 7 is opened. There is no. Therefore, the brazing chamber 4 and the cooling chamber 5 can be maintained in a low oxygen atmosphere.

  Then, the inlet door 39 of the carry-out vacuum purge chamber 7 is closed, and the argon gas vacuum pump 58 in the carry-out vacuum purge chamber 7 is operated to collect the argon gas in the carry-out vacuum purge chamber 7 in the collection tank 10. Next, the pressure is returned to the atmosphere by the atmospheric pressure return pipe 77, and then the outlet door 40 of the carry-out vacuum purge chamber 7 is opened, and the brazed aluminum product is taken out to the outlet table 17.

  When the argon gas recovered in the recovery tank 10 exceeds the recovery capacity, excess argon gas is exhausted from the argon gas exhaust pipe 62.

  As described above, in the brazing furnace 1 for aluminum products according to the present invention, the brazing chamber 4 and the cooling chamber 5 can be completely sealed when carrying out the brazing operation, and the carry-in vacuum The purge chamber 2 and the carry-out vacuum purge chamber 7 are provided with inlet doors 35 and 39 and outlet doors 36 and 40, respectively. When carrying aluminum product into the brazing chamber 4 and carrying out from the cooling chamber 5, air and argon are introduced. It is configured to exchange gas. For this reason, a substance that causes disturbance in the brazing operation such as air is not mixed into the brazing chamber 4 and the cooling chamber 5 furnace.

  Furthermore, since the brazing furnace 1 for aluminum products is made of a non-oxidizing material such as a muffle, a heat insulating material, and a conveyor belt, the furnace interior should be kept in a low oxygen atmosphere. Can do.

  Therefore, since the brazing chamber 4 and the cooling chamber 5 can be maintained in a low oxygen atmosphere, the brazing operation can be performed without reducing the brazing quality without using a flux in the brazing process. . Since no flux is used, excess flux and flux residues are not mixed in the argon gas.

  Therefore, unlike the prior art, there is no need to continuously exhaust argon gas mixed with disturbances such as flux and constantly reinforce fresh argon gas. Argon gas needs to be supplied from the recovery tank 10 to the carry-in vacuum purge chamber 2 and the carry-out vacuum purge chamber 7 and recovered, but the amount of argon gas used is smaller than that of the conventional brazing furnace 1 for aluminum products. Very small amount and good economic effect.

  FIG. 2 is a diagram showing an overall configuration of a brazing furnace 81 for an aluminum product according to Embodiment 2 of the present invention. The aluminum product brazing furnace 1 of Example 1 is provided with a conveyor belt device 8 as a conveying means for conveying the aluminum product to be brazed through the brazing furnace 1 as shown in FIG.

  In contrast, the aluminum product brazing furnace 81 of Example 2 is provided with a transport roller hearth device 82 as means for transporting the aluminum product to be brazed in the brazing furnace 81 as shown in FIG. ing.

  Except for the configuration in which the transport roller hearth device 82 is provided as the transport means (the configuration of the roller hearth furnace), the second embodiment has the same configuration including the first embodiment and the control device 75, and has the same functions and effects. Therefore, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  In the aluminum product brazing furnace 81 of the second embodiment, as shown in FIG. 3, a plurality of rollers 83 constituting the transport roller hearth device 82 are arranged from the carry-in vacuum purge chamber 2 to the carry-out vacuum purge chamber 7. . A roller 83 provided in the rear chamber 6 is configured to be driven by a roller driving device 87 via a chain 86. The roller 83 provided in the front chamber 3 may be configured to be driven by a roller driving device via a chain.

  Specifically, although not shown, a chain 86 is hung between a sprocket fixed to the rotating shaft of the roller 83 protruding outward from the rear chamber 6 and a sprocket fixed to the driving shaft of the roller driving device 87. It is said.

  Although not shown, a chain is hung between the plurality of rollers 83 constituting the transport roller hearth device 82 on the outer side of the brazing furnace 81, and the plurality of rollers 83 are formed by the roller driving device 87. The aluminum products to be brazed, which are driven in conjunction with each other and placed on the conveying roller hearth device 82, are conveyed.

  The conveying unit of the conveying roller hearth device 82 is provided in the brazing chamber 4 so as to pass through the muffle 26. The roller 83 which comprises the conveyance roller hearth apparatus 82 is formed with the heat resistant steel or the carbon fiber reinforced carbon composite material similarly to the conveyance belt 31 in the first embodiment.

  As mentioned above, although the form for implementing the brazing furnace of the aluminum product which concerns on this invention was demonstrated based on the Example, this invention is not limited to such an Example, and is described in a claim It goes without saying that there are various embodiments within the scope of the technical matters stated.

  Since the brazing furnace for aluminum products according to the present invention is configured as described above, it can be applied to various aluminum products including automobile parts such as aluminum heat exchangers.

1 Brazing furnace for aluminum products
2 Loading vacuum purge chamber
3 front room
4 Brazing room
5 Cooling room
6 Rear room
7 Unloading vacuum purge chamber
8 Conveyor belt device
9 Argon gas piping system
10 Collection tank
11 Air exhaust system
16 Entrance table
17 Exit table
20 Furnace wall
21 Furnace room
22 Insulation
26 Muffle
27 Heater
28 Heating passage
31 Conveyor belt
32 Belt drive
33 Belt pulley
35 Entrance vacuum purge chamber entrance door
36 Exit door
39 Entrance door of unloading vacuum purge chamber
40 Exit door
45 Argon gas source
46 Supply pump
47 Argon gas source supply pipe
50 Argon gas supply pipe
51 Supply pump
54 Purge feed pump
55 Purge feed argon gas supply pipe
58 Vacuum pump for argon gas
59 Argon gas recovery tube
62 Argon gas exhaust pipe
63 Vacuum pump for air
64 Air exhaust pipe
70 In-furnace pressure sensor
71 Cooling chamber pressure sensor
72 Load vacuum purge chamber pressure sensor
73 Unloading vacuum purge chamber pressure sensor 75 Controller
76, 77 Atmospheric pressure return pipe 81 Brazing furnace for aluminum products 82 Conveyor roller hearth device 83 Roller 86 Chain 87 Roller drive device

Claims (5)

Aluminum product brazing furnace comprising a carry-in vacuum purge chamber, a brazing chamber, a cooling chamber, a carry-out vacuum purge chamber, and a conveying belt device or a conveying roller hearth device provided through the brazing chamber and the cooling chamber Because
The brazing chamber and the cooling chamber are filled with argon gas, and a part of the argon gas can be supplied to the recovery tank. The argon gas in the recovery tank is supplied to the carry-in vacuum purge chamber and the carry-out vacuum purge chamber, and is carried in. It can be recovered from the vacuum purge chamber and the discharge vacuum purge chamber,
The air in the carry-in vacuum purge chamber and the carry-out vacuum purge chamber can be evacuated and filled with argon gas in the recovery tank when the aluminum product to be brazed is carried into the brazing chamber and when the aluminum product being brazed is carried out from the cooling chamber. And the configuration
The pressure in the brazing chamber and the cooling chamber filled with argon gas is configured to be higher than that of the carry-in vacuum purge chamber and the carry-out vacuum purge chamber filled with argon gas,
A brazing furnace for aluminum products, which enables brazing of aluminum products without using flux. Carry-in vacuum purge chamber, brazing chamber, cooling chamber, unloading vacuum purge chamber, transport belt device or transport roller hearth device provided through the brazing chamber and cooling chamber, argon gas piping system, and argon gas An aluminum product brazing furnace equipped with a recovery tank and an air exhaust system,
The brazing chamber includes a furnace chamber formed by being surrounded by a graphite heat insulating material. The furnace chamber includes a graphite muffle extending in the longitudinal direction of the furnace chamber, and a plurality of radiant tubes installed outside the muffle. Having a heater or a silicon carbide heater,
The belt of the conveying belt device or the roller of the conveying roller hearth device is formed of heat-resistant steel or carbon fiber reinforced carbon composite material, and the conveying unit of the conveying belt device or the conveying roller hearth device passes through the muffle,
The argon gas piping system is filled with argon gas in the brazing chamber and the cooling chamber, and a part of the argon gas is supplied to the recovery tank, and the argon gas in the recovery tank is supplied to the carry-in vacuum purge chamber and the carry-out vacuum purge chamber. Can be recovered from the carry-in vacuum purge chamber and the carry-out vacuum purge chamber,
When the brazing aluminum product is carried into the brazing chamber and when the brazing aluminum product is carried out of the cooling chamber, the air in the carry-in vacuum purge chamber and the carry-out vacuum purge chamber is exhausted and filled with argon gas supplied from the recovery tank. Is a configuration to
The pressure in the brazing chamber and the cooling chamber filled with argon gas is configured to be higher than that of the carry-in vacuum purge chamber and the carry-out vacuum purge chamber filled with argon gas,
A brazing furnace for aluminum products, which enables brazing of aluminum products without using flux. The argon gas piping system includes an argon gas source supply pipe that supplies argon gas to the brazing chamber, an argon gas supply pipe that supplies argon gas from the brazing chamber and the cooling chamber to the argon gas recovery tank, and collects the argon gas The argon gas sucked by the vacuum pump for argon gas is recovered to the recovery tank from the purge feed argon gas supply pipe supplied from the tank to the carry-in vacuum purge chamber and the carry-out vacuum purge chamber, and the carry-in vacuum purge chamber and the carry-out vacuum purge chamber. An argon gas recovery pipe,
3. The brazing furnace for aluminum products according to claim 2, wherein the air exhaust system includes an air exhaust pipe for exhausting air sucked by a vacuum pump for air from each of the carry-in vacuum purge chamber and the carry-out vacuum purge chamber. .   The carry-in vacuum purge chamber and the carry-out vacuum purge chamber each have an entrance door and an exit door that can be opened and closed independently, and when the aluminum product to be brazed is carried into the brazing chamber and from the cooling chamber When carrying out, the carry-in vacuum purge chamber and the carry-out vacuum purge chamber are closed by closing the entrance door and the exit door, respectively, and after being evacuated, filled with argon gas, and then the exit door of the carry-in vacuum purge chamber 4. An aluminum product brazing furnace according to claim 3, wherein the entrance door of the carry-out vacuum purge chamber is opened.   A front chamber is integrally provided at the front of the brazing chamber, a rear chamber is integrally provided at the rear of the cooling chamber, and belt pulleys before and after the conveyor belt device are provided in the front chamber and the rear chamber. The aluminum product according to claim 4, wherein the roller of the transport roller hearth device provided in any one of the front chamber and the rear chamber is driven by a roller driving device. Brazing furnace.

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