JPH079126A - Heat transmission brazing device - Google Patents

Abstract

PURPOSE:To prevent the movement of members to be joined sticking to a heating element during brazing together with the heating element and peeling of the joined parts by providing the brazing device with a retaining member for pressing the members to be joined in a direction opposite to the moving direction of the heating member. CONSTITUTION:The compression quantity of a coil spring 3 increases gradually and the pressing force in a pressing direction is imparted on the upper member to be joined when a heater head 1 is lowered. Heat is conducted to the members 10 to be joined from a front end heating part 1a and a brazing filler metal is melted, by which the upper and lower members 10, 10 to be joined are joined. The head 1 is risen and is parted from the members 10 to be joined when the brazing is completed. The compression quantity of the coil spring 3 decreases gradually and the pressing force of the coil spring 3 on the members 10 to be joined decreases as well as the head 1 ascends. The spring 3 parts from the members 10 to be joined as well and ascends after the head 1 ascends until the compression of the coil spring 3 is completely released.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat transfer brazing device used for joining members to be joined made of metal such as aluminum (including its alloy).

[0002]

2. Description of the Related Art For example, as a joining method for partially joining aluminum materials, copper and other electrodes are placed in contact with the members to be joined which are placed in a superposed state at a site to be joined, and the members to be joined are pressed under pressure. BACKGROUND ART Resistance spot welding is performed in which an electric current is applied to a predetermined joining portion, and resistance heating due to the electric current raises the temperature of the joining portion to perform welding. In addition, brazing in the atmosphere such as torch brazing and high frequency brazing is also performed.

However, in the above resistance spot welding method, since the specific resistance of the aluminum material is small,
There are drawbacks such that a large current is required to obtain the amount of heat required for welding and that the electrode dressing interval is shortened because an alloy of copper and aluminum is easily formed at the electrode tip. On the other hand, in the torch brazing method and the high frequency brazing method, it is physically difficult to perform heating and pressurizing at the same time. It had the drawback of being long.

Therefore, as an alternative joining method, a brazing material having a lower melting point than that of the members to be joined is interposed at the joining interface, and the heating element is brought into contact with the members to be joined under pressure.
A heat transfer brazing method has been developed in which the brazing filler metal is melted mainly by heat conduction from the heating element, and thus both members to be joined are joined. According to this method, there is an advantage that a wide range of parts can be easily joined in the atmosphere and the energy cost is small.

[0005]

In such a heat transfer brazing method, after the brazing, the heating element brought into contact with the members to be joined is moved in the separating direction, and there is a risk of melting the members to be joined due to excessive heating. It is made possible to avoid such problems.

However, it is often the case that the member to be welded adheres to the heating element brought into contact with the members to be welded during brazing. In this case, when the heating element is moved in the separating direction, There is a defect that the joint member also moves together and the joint part is separated, or the jointed member is excessively heated and melted.

The present invention has been made in order to solve the above drawbacks, and it is a transmission that prevents the members to be joined attached to the heating element from moving together with the heating element during the movement of the heating element after brazing. It is intended to provide a heat brazing device.

[0008]

In order to achieve the above-mentioned object, the present invention will be described with reference to the reference numerals in the drawings. The present invention is made of metal and is opposed to each other with a brazing material (11) interposed at a joint interface. It is arranged so that it can come in and out of contact with the joining member (10),
A heating element (1) that melts the brazing filler metal mainly by heat conduction due to contact with the members to be joined, and a heating element (1) disposed in the vicinity of the heating element (1) so as to be contactable with and separable from the members to be joined (10), The member to be joined (10) is moved when the heating element (1) in contact with the member to be joined is moved in the direction away from the member to be joined (10).
A heat transfer brazing device is characterized by comprising a pressing member (3) for pressing the heating element (1) in a direction opposite to the moving direction of the heating element (1).

In the above description, "mainly" means that it is not necessary that all the heat be transferred by contact, but that a part of the heat be transferred by radiation or convection.

Preferably, the pressing member (3) is composed of a coil spring into which the heating element (1) is inserted through its axis and which expands and contracts in the advancing and retracting direction of the heating element (1). It is preferable that the tip portion (3a) protrudes from the heating element (1) toward the joined member (10).

[0011]

After brazing, when the heating element (1) contacting the member to be joined (10) is separated, the holding member (3) holds the member to be joined in the direction opposite to the moving direction of the heating element. The member to be joined (10) attached to the heating element (1) during brazing is
It is possible to prevent a risk that the joint portion is peeled off by moving together with the heating element. Further, it is possible to rapidly cool the brazed portion with an air jet or the like while keeping the pressed state, and to bake.

[0012]

Embodiments of the present invention will now be described with reference to the drawings.

In FIG. 2, (1) is a cylindrical heater head as a heating element, and the heater head is attached to the center of the lower surface of the base portion (2) having a bulging upper end in a hanging shape. The heater head (1) can be moved up and down together with the base portion (2) through a driving device (not shown). When the brazing is performed, the heater head (1) moves forward and backward in the approaching direction to the members to be joined, and the tip heating portion (1a). ) Is brought into contact with the members to be joined under pressure, and the brazing material is melted by the heat conduction. After brazing, it moves upward and separates from the members to be joined.

In the heater head (1), the coil spring (3) has its axial center penetrated by the heater head (1), and the upper end of the coil spring (3) is on the lower surface of the base (2). It is installed in a fixed state. Therefore, the coil spring (3) moves up and down as the heater head (1) moves up and down, and can be expanded and contracted in the up and down direction. The coil spring (3) moves the heater head (1) in contact with the members to be welded after the brazing is completed and separates the heater head (1) from the members to be welded.
By applying a pressing force to the members to be joined in a direction opposite to the moving direction of the member, the member to be joined attached to the heater head (1) is prevented from moving together with the heater head (1) and peeling off the joined portion. To fulfill. For this,
As shown in FIG. 2, the length of the coil spring (3) in a non-expanded state, that is, in a natural state in which neither compression nor expansion is performed, the spring tip portion (3a) has a tip heating portion (1) of the heater head (1).
It is set so as to project downward from a), and the spring is in a compressed state when the tip heating portion (1a) of the heater head (1) is in contact with the members to be joined.

An example of the heat transfer brazing method using the brazing apparatus shown in FIG. 2 is as follows.

That is, first, as shown in FIG. 3, the melting point is lower than that of the joined members between the joined portions (10a) (10a) of the two joined members (10) (10) made of aluminum or the like. The brazing material (11) is arranged in an intervening state. The joint (10a
) (10a) is supplied with flux as needed. The flux may be applied to the surface of the brazing filler metal (11), but in a preferred embodiment, it is preferable to use a flux-containing brazing filler metal that does not require flux application. As an example of the flux-containing brazing filler metal, a powder of an Al alloy containing an element such as Si or Zn, or a powder of a simple substance of these component elements is mixed with a fluoride-based flux or a chloride-based flux. An example thereof is a mixture of the powder mixture that has been hot pressed and then molded into a desired shape by extrusion molding or the like. Further, as a typical composition of such a solid brazing material, A
1, Si, 3 to 15 wt% of Si based on the total content of metal components excluding fluoride flux, the total of elements excluding fluoride flux and fluoride flux. In a weight ratio of 99.9: 0.1-7
The content may be 0:30 and the density is 90% or more of the theoretical value. Further, as the brazing material, a mixture of the above alloy powder or a single powder of the alloy composition and the flux powder with a liquid binder may be used.

Next, the members to be joined (10) (10) with the brazing material (11) interposed therebetween are placed on a support base (12) made of a heat insulating material such as rock wool, and a heater is preheated. The head (1) is moved down above the joint (10a). By the downward movement of the heater head (1), the tip portion (3a) of the coil spring (3) first comes into contact with the upper joined member (10). When the heater head (1) is further lowered, the amount of compression of the coil spring gradually increases, and the elastic force associated with this gradually applies a pressing force in the pressing direction to the upper joined member. Then, the heater head (1) is further lowered, and the tip heating part (1a) is brought into pressure contact with the position corresponding to the bonding part of the member (10) to be bonded with a predetermined pressing force.

Due to the contact of the heater head (1), heat is conducted from the tip heating portion (1a) to the upper joined member (10) and further conducted to the brazing material (11). The members to be joined (11) (11) are joined.

When the brazing is completed, as shown in FIG.
The heater head (1) is moved upward to move the members (1
0) away from. Thus, the upper joined member (10)
Is subjected to downward pressure by the coil spring until the coil spring is decompressed, even if the upper joined member (10) adheres to the heater head (1) and tries to move upward together with the heater head. The pressing force of the coil spring (3) acts in a direction to separate the upper joined member (10) from the heater head (1), and the heater head (1) is smoothly separated from the joined member (10). In this state, if necessary, the brazing part may be rapidly cooled by an air jet or the like, and a treatment such as hardening may be performed.

As the heater head (1) rises,
The amount of compression of the coil spring (3) gradually decreases, and the pressing force of the coil spring (3) on the joined member (10) also decreases.
Then, after the heater head (1) is raised until the compression of the coil spring (3) is completely released, the coil spring (3) also rises apart from the joined member (10).

In the above embodiments, the coil spring (3) is used as the pressing member for pressing the joined member (10) when the heater head (1) is separated from the joined member (10). It is not limited to springs. Also,
Although the heating element is contacted only from one side of the joint (10a), the heating element may be contacted from both sides with the joint in between.

[0022]

As described above, according to the present invention, after the brazing is completed, when the heating element that is in contact with the member to be joined is separated, the holding member holds the member to be joined in the direction opposite to the moving direction of the heating element. Therefore, it is possible to prevent the member to be joined, which adheres to the heating element during brazing, from moving together with the heating element and peeling off the joint. Moreover, it is possible to prevent a risk that the member to be joined adheres to the heating element for a long time and is excessively heated, and the member to be joined is melted.

[Brief description of drawings]

1 is a cross-sectional view showing a state immediately after completion of heat transfer brazing using the brazing apparatus of FIG.

2A and 2B are views showing a brazing device according to an embodiment of the present invention, wherein FIG. 2A is a front view and FIG. 2B is a bottom view.

3 is a cross-sectional view showing a state during brazing of heat transfer brazing using the brazing apparatus of FIG.

[Explanation of symbols]

 1 ... Heater head (heating element) 1a ... Tip heating part 3 ... Coil spring (pressing member) 10 ... Joined member 11 ... Brazing material

Claims (2)

[Claims] 1. A heat generated by contact with a member to be joined, which is arranged so as to be freely attached to and detached from a member to be joined (10) made of metal, which is opposed to the joined interface with a brazing material (11) interposed therebetween. Heating element that melts the brazing material by conduction (1)
And a heating element (1) arranged in the vicinity of the heating element (1) so as to be in contact with and separated from the joined member (10) and in contact with the joined member.
And a pressing member (3) for pressing the joined member (10) in a direction opposite to the moving direction of the heating element (1) when the joined member (10) moves in a direction away from the joined member (10). Heat transfer brazing device. 2. The pressing member (3) is composed of a coil spring into which the heating element (1) is inserted in the axial center thereof and which expands and contracts in the advancing and retracting direction of the heating element (1). Part (3a) is joined member (10) rather than heating element (1)
The heat transfer brazing device according to claim 1, which projects to the side.