JPH11300477A - Multistage pressure force welding equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to stably weld in a short time by changing the pressure force in many stages. SOLUTION: First and second electrodes 4 and 5 are press-fixed respectively to a tongue 2 holding an armature wire 1 and a brush surface 3 which is integrated with this tongue 2, and both electrodes are energized. And, the first electrode 4 is made possible to be directly pressured by a cylinder 7, and the pressure of the cylinder 7 is controlled by an electropneumatic regulator 8. By changing the control voltage of the electropneumatic regulator 8, the pressure of the cylinder 7 is changed. By a mechanism that at the beginning of a welding process, the pressure force of the cylinder 7 is made weak and is gradually made strong, a weld time is shortened and weld quality is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-stage pressure welding apparatus most suitable for welding an armature wire to a commutator tongue.

[0002]

2. Description of the Related Art Generally, an armature wire (hereinafter referred to as a "wire") is used.
Is welded to the commutator tongue (hereinafter referred to as “tongue”) by pressing the electrodes on the tongue and the brush surface, applying electricity between the two electrodes, and using the resistance heat generated between the tongue and the electrodes. Is melted to weld the wire to the tongue.

Conventionally, as a method of welding a wire and a tongue of this type, as shown in FIG. 3, a first electrode 14 made of high-resistance tungsten having an extremely high melting point is attached to a tongue 2 holding a wire 1 therebetween. The second electrode 15 made of low-resistance copper is applied to the brush surface 3 integrated with the tongue 2 while being pressed.
And a transformer 16 for pressing both electrodes 14 and 15 downward and controlling the current between the electrodes 14 and 15.
In this case, heat is generated by contact resistance between the tongue 2 and the first electrode 14 by passing a current through the tongue 2.

In such a conventional welding apparatus, the first electrode is pressed against the tongue 2 with a constant pressing force via a spring attached to the tip of the cylinder rod. If necessary, the spring unit was replaced each time.

[0005]

However, in such a conventional welding apparatus, since the pressing force is always set to a constant value by a spring during the welding process, when welding the wire to the tongue, the welding force must first be set. From the stage where current is applied to the tongue by applying a current with a pressing force that does not bend the tongue, heat is transmitted from the electrode to the tongue, the stage where the tongue is bent and the tip of the tongue comes into contact with the brush surface It was difficult to change the pressing force until the step of welding to the brush surface while extruding.

Therefore, there has been a problem that setting an optimum pressing force at a specific stage becomes inappropriate at other stages. For example, if the pressing force is increased and the electrode is forcibly pressed to the tongue in order to ensure pressure bonding, there is a possibility that contact resistance is reduced, heat generation is reduced, and welding is insufficient. In addition, since the surface condition of the commutator is different for each armature, the amount of heat generated is not stable at the same pressing force.

[0007] The present invention has been made in view of the above points, and an object of the present invention is to provide a multi-stage press-welding apparatus capable of constantly and stably welding in a short time by changing the pressurization in multiple stages. And

[0008]

In order to achieve the above object, the present invention provides a commutator tongue holding an armature wire having an insulating coating and a brush surface integral with the commutator tongue. By applying pressure between the first and second electrodes by crimping the second electrode and changing the pressing force of the first electrode in multiple stages, the distance between the commutator tongue and the first electrode is increased. A low friction cylinder for pressurizing the first electrode against the commutator tongue, wherein the armature wire is welded to the commutator tongue by resistance heat generated in the cylinder. An object of the present invention is to provide a multi-stage pressure welding apparatus provided with an electropneumatic regulator for controlling the pressure of a low friction cylinder.

According to the present invention, the pressure applied to the tongue of the first electrode is changed almost instantaneously by changing the control voltage of the electropneumatic regulator to change the pressure of the cylinder. This makes it possible to set optimum pressurizing conditions for the wire welding process. As a result, the number of components in the pressurizing section can be reduced and supply can be performed at a low cost, and the welding time can be shortened by setting the optimal pressurizing conditions, and the welding quality can be greatly improved.

[0010]

Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 is a configuration and a circuit diagram showing an embodiment of the present invention, and portions corresponding to FIG. 3 are denoted by the same reference numerals.

The first electrode 4 of the welding device is pressed against the tongue 2 of the armature 10 and the second electrode 5 is
The current path circulates from the first electrode 4 through the second electrode 5 via the transformer 6 by being pressed against the zero brush surface 3. The first electrode 4 can be directly pressed by a rod 7a of a low-friction cylinder (hereinafter simply referred to as "cylinder") 7 without using a spring, and the head side of the cylinder 7 is controlled by a throttle 9a and a check valve 9b. It is connected to an air source P via a valve 9 and a fast response electropneumatic regulator 8. Here, the electropneumatic regulator means a device that obtains a regulated pneumatic output with respect to an electrical input signal. The rod side of the cylinder 7 is connected to a similar flow control valve 9.
And an air source P via a switching valve 11.

With such a configuration, a predetermined signal voltage is applied to the first electrode 4 via the rod 7a of the cylinder 7 by applying a required signal voltage from a signal oscillator (not shown) to the electropneumatic regulator 8, By sequentially changing the signal voltage to change the pressing force of the first electrode 4, multi-stage pressurization becomes possible.

FIG. 2 shows a state in which a signal voltage is applied to the electropneumatic regulator 8 so that a pressure of 35 kg (1.7 kg / cm ² ) is generated in the cylinder 7 having a volume of 15 cc. FIG. 9 is a diagram showing an example of a data curve when a pressure of 50 kg (2.9 kg / cm ² ) is generated, and the signal voltage is again reduced to reduce the pressure to 35 kg.

In the above-mentioned diagram, in the first step of the time 0 to 0.1 sec, the pressure on the rod 7a side of the cylinder 7 is released to the atmosphere, and the rod 7a is maintained at the pressure of 35 kg for 0.1 sec. In the second step of the forward movement state, time 0.1 to 0.4 sec, the pressure of the rod 7a is increased from 35 kg to 50 kg in the time of 0.2 sec, and the second half of 0.1 sec is maintained as it is in the time 0 sec. The third step of 0.4-0.5 sec is time 0.5
Each state shows that the rod 7a is moved forward by 5 mm in 1 second and the voltage of the electropneumatic regulator 8 is set so that the applied pressure becomes 35 kg.

When the above steps are applied to the step of welding the wire 1 to the tongue 2 of the armature 10, in the first step,
The heat from the first electrode 1 can be applied to the tongue 2 with a pressing force that does not push and bend the tongue 2 around which the wire 1 is wound. In the second step, the tongue 2 is bent and its tip is placed on the brush surface 3. Can be pressed. Further, in the third step, the wire can be welded to the brush surface while increasing the pressure and burning out the insulating coating of the wire and pushing it out to the side. As described above, it is desirable that the pressing force of the cylinder 7 at the time of wire welding is initially weak and gradually increased.

In this respect, in the above embodiment, the pressing force of the cylinder 7 is controlled by the electropneumatic regulator 8, so that the pressing force is required almost instantaneously by changing the signal voltage applied to the electropneumatic regulator. Can be changed. In addition, a pressurizing spring, which is required in a conventional welding apparatus, is not required, and stable welding can be performed with an extremely simple configuration.

In the above embodiment, the case where the present invention is used for welding a wire and a tongue has been described. However, the present invention is not necessarily limited to this, and all weldings in which multi-stage welding is effective are used. Can be applied to Further, in this embodiment, the case where the pressing force is changed in two stages has been described, but the pressing force can be changed in three or more stages as necessary.

[0018]

As described above, according to the multi-stage pressure welding apparatus according to the present invention, the pressure of the cylinder is changed by changing the control voltage of the electropneumatic regulator to change the pressure almost instantaneously. Optimum pressing conditions can be set for each welding process. This makes it possible to reduce welding time and improve welding quality with a simple configuration.

[Brief description of the drawings]

FIG. 1 is a configuration and a circuit diagram showing an embodiment of the present invention.

FIG. 2 is a diagram showing a change in the pressing force over time.

FIG. 3 is a perspective view showing an example of a conventional welding device.

[Explanation of symbols]

 1: armature wire 2: commutator tongue 3: brush surface 4: first electrode 5: second electrode 6: transformer 7: low friction cylinder 8: electropneumatic regulator 10: armature

Claims (1)

[Claims] A first and a second electrode are pressed against a commutator tongue holding an armature wire having an insulating film and a brush surface integral with the commutator tongue, respectively. By energizing between the electrodes and changing the pressure of the first electrode in multiple stages, the armature wire is connected to the commutator tongue by resistance heat generated between the commutator tongue and the first electrode. A low friction cylinder for pressing the first electrode to the commutator tongue, and an electropneumatic regulator for controlling the pressure of the low friction cylinder. A multi-stage pressure welding apparatus characterized by the above-mentioned.