JPH0661632B2 - Friction welding method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a friction welding method in which two end members are relatively rotated in a state where the end faces thereof are in contact with each other and the two members are joined by friction heat generated.

(Prior art) The friction welding method is roughly classified into a braking method and an inertia method. The former is a method of applying upset pressure after stopping the rotation of the spindle, and the latter is a method of gradually decelerating and stopping the rotation of the spindle. Upset pressure is applied to. Then, in any of the methods, if the deviation of the member due to the application of the upset pressure is not constant, the product dimensions will vary.

As means for solving this, those disclosed in JP-A-55-92284 and JP-B-59-45472 are known.

The means disclosed in Japanese Patent Laid-Open No. 55-92284 detects the contact time point of two members joined to each other by energizing both members, and with this time point as a reference, the rotation of the spindle is stopped using two timers. The means disclosed in Japanese Patent Publication No. 59-45472 detects the contact position of two members to be joined to each other, and with this position as a reference, the other member of one member is detected. The amount of movement to the side is continuously detected, and when the amount of movement reaches a set amount, the rotation of the spindle is stopped and the upset is performed.

(Problems to be Solved by the Invention) No matter which method is adopted in the above-mentioned conventional method, it is necessary to detect a contact time point or a contact position of both members and store the detected time point. Alternatively, a timer that operates on the basis of the position or a means for measuring a mechanical displacement amount is required, and the mechanism of the apparatus itself becomes complicated.

(Means for Solving Problems) In order to solve the above problems, the present invention utilizes that the deviation of members to be joined to each other corresponds to the resistance value measured by energizing between the members. The spindle rotation is stopped based on the resistance value.

(Function) If the inertia method is used, the spindle rotation is gradually decelerated from when the resistance value reaches the set value and upset pressure is applied, and if the brake method is used, the spindle is rotated when the resistance value reaches the set value. Stop the rotation of and then apply the abset pressure.

(Example) Below, the Example of this invention is described based on an accompanying drawing.

FIG. 1 is an overall view of a friction welding apparatus for carrying out the method of the present invention,
FIG. 2 is a graph showing the relationship between the resistance value and the margin of deviation, etc. when the members to be joined together are energized.

The friction welding device is provided with a fixing unit 10 and a spindle 20 on a base 1.

The fixing unit 10 attaches chuck claws 13 and 13 insulated from the chuck body 11 to the ceramic body 11 and holds the umbrella work W1 as one of the members joined to each other by the chuck claws 13 and 13. End piece 1 of the umbrella work W1 with ceramic insulation
4, and the chuck claw 13 is connected to the controller via a conductive switch 15.

On the other hand, in the spindle unit 20, the slider 22 of the moving table 21 is engaged with the rail 2 provided on the base 1, and the moving table 21 is moved forward and backward in the drawing by the operation of the upsetting cylinder unit 23. .

A spindle unit 25, which is rotated by an AC spindle motor 24, is fixed to the moving table 21, and a collet chuck 26 for holding the stem work W2 as the other member joined to each other is provided in the spindle unit 25. Cylinder unit 27 fixed to the rear part of movable table 21 is used to open and close 26. A slip ring 28 is fitted to the rear end of the spindle unit 25, and the slip ring 28
A conductive switch 29 is attached to the stem work W2, and the stem work W2 is connected to the controller via the conductive switch 29. The moving amount of the moving table 21 is measured by the magnet scale 30.

In the above, in order to friction-weld the umbrella work W1 and the stem work W2, the umbrella work W1 is moved by the chuck claws 13 and 13 with the movable table 21 retracted to the right in the figure by the upsetting cylinder unit 23. Grasp the stem work W2 with the collet chuck 26, rotate the stem work W2 by driving the spindle motor 24, and move the stem work W2 forward by the upsetting cylinder unit 23 in the direction of the umbrella work W1. The end face is heated by the heat generated at this time, and an upset force is applied by the upset cylinder unit 23 to press the end face.

By the way, in the above-mentioned joining process, in the present invention, the rotation stop or deceleration start time of the spindle motor 24 is performed based on the resistance value measured by energizing the works W1, W2.

The specific content will be described with reference to FIG. In FIG. 2, the horizontal axis represents time, and the vertical axis represents electric resistance, offset (movement amount of magnet scale), spindle motor rotation speed, and workpiece contact surface temperature, and line a in the figure represents electric resistance. The line segment b represents the deviation, the line segment c represents the number of revolutions of the spindle motor, and the line segment d represents the temperature of the work contact surface over time.

As can be seen from FIG. 2, the temperature of the work is constant as shown by the line segment d1 in the state before the works W1 and W2 are brought into contact with each other, but after the contact, the line segment d is caused by frictional heat due to rotation.
As shown in 2, the temperature of the work contact surface gradually rises.

On the other hand, until the workpieces W1 and W2 come into contact with each other, they are in an insulated state as shown by the line segment a1, but at the time point a3 when the workpieces W1 and W2 come into contact with each other, the electric resistance value becomes substantially zero, and then the temperature rises. At the same time, the electric resistance value gradually increases as shown by the line segment a2. Then, when the works W1 and W2 are pressed while the contact end face is heated, the deviation amount gradually increases as shown by the line segment b. That is, the temperature of the contact surface of the work, the electric resistance value, and the deviation are related to each other.
The resistance value when the target deviation b1 is uniquely determined, and when this resistance value is R1, the spindle motor 2
The rotation of 4 may be stopped when the resistance value becomes R1.

In order to stop the spindle motor 24 when the resistance value becomes R1, in the inertia system, the spindle motor 24 may be gradually decelerated from the time point of c1. For this purpose, when the resistance value becomes R2. It is sufficient to start deceleration of the spindle motor 24 assuming that is c1.

That is, if the target deviation is set, the resistance value R1 corresponding to this deviation is determined, and if the resistance R1 is known, the deceleration start time of the spindle motor can be determined. The time point can be determined by the resistance value R2. Therefore, if the deceleration of the spindle motor 24 is started when the resistance value measured by energization becomes R2, the margin is set when the motor stops.

In addition, although the friction welding method of the inertia system is shown in the embodiment, in the case of the braking system, the rotation of the spindle motor is stopped when the resistance value reaches the set value, and then the upset pressure is applied. To

(Effects of the Invention) As described above, according to the present invention, the rotation of the spindle motor is stopped based on the resistance value by utilizing the correspondence between the resistance value and the margin when the work is energized. As a result, the amount of deviation can be made constant, and there is no need to detect the contact point or contact position of the work as in the conventional case, so the mechanism can be simplified.

[Brief description of drawings]

FIG. 1 is an overall view of a friction welding apparatus used for carrying out the method of the present invention, and FIG. 2 is a graph showing a relationship between a resistance value when a work is energized and a deviation margin. In the drawing, 10 is a fixed unit, 20 is a spindle unit, 23 is an upset cylinder unit, 24 is a spindle motor, and W1 and W2 are members joined to each other.

Front page continuation (72) Inventor Akira Takeshima 1-10-1 Shin-Sayama, Sayama-shi, Saitama Honda Engineering Co., Ltd. (72) Hideki Komori 1-10-1 Shin-Sayama, Sayama-shi, Saitama Honda Engineering Co., Ltd. In-house (56) References Japanese Patent Publication No. 59-15752 (JP, B2) Actual Publication No. 51-23625 (JP, Y2)

Claims (1)

[Claims] 1. In a state in which the end faces of two members are in contact with each other, one member is pressed against the other member while being relatively rotated by a spindle, and friction heat is generated on the end faces of both members, so that both members are pressed against each other. In the friction welding method to be joined,
A friction is characterized in that electricity is applied between the members, a resistance value that increases as the member temperature rises due to frictional heat is measured, and the rotation of the spindle is stopped when the resistance value reaches a set value. Welding method.