Installation method and process of flexible bearing of harmonic reducer

The flexible bearing of harmonic reducer is a kind of bearing of harmonic reducer. It is a kind of bearing used outside the harmonic generator, which can realize the speed change requirement of large transmission ratio. Because of its special overall structure, it is installed in time is different from other types of bearings.

Assembly method of flexible bearing of harmonic reducer

1. Arc fill ball groove method

This method is actually that when the ball filling angle is greater than 195°, a circular arc groove that is larger than the diameter of the steel ball is opened in the distance from the inner and outer ring ribs to the bottom diameter of the groove. The steel balls are respectively filled into the channels. The arc ball-filling groove method has low installation efficiency, high production cost, and poor quality control, because if the ball-filling groove is deep, the ferrule will be scrapped; if it is shallow, the steel balls cannot be filled. Improper grooving will greatly reduce high-speed performance and limit axial play.

2. Conventional ball filling method

The finishing ball filling method traditionally applies a radial force to the outer ring between the 186-195° filling angle to make it elastically deform to fill a finishing ball. This method is relatively common, but there are still steel balls. The problem of being pinched and plastic deformation of the ferrule.

3. Breaking ball method

When the operating conditions, rotational speed and vibration requirements of the bearing are low and the ball filling angle is greater than 195°, the fracture ball filling method can be used. This method needs to open a small groove on the inner diameter before the heat treatment of the outer ring, and the stress concentration is generated by the heat treatment. steel ball. This method can effectively increase the number of balls filled, but it will sacrifice the performance of the bearing.

4. Elastic filling method

The elastic filling method is a method in which the steel balls are filled into the channel by expanding the radial tensile deformation of the bearing ring within the allowable range of the tensile stress of the bearing ring. The main force is to press the end face of the outer ring. When the outer ring is pressed down, the steel ball will continue to expand the outer ring and become the tension of the steel ball to the outer ring in the radial direction. The number of balls is also increasing, and the tension on the outer ring is also increasing, until the steel balls are fully opened into the channel. The force process is shown in the figure. This method can theoretically meet the filling requirements of 360° filling angle. After calculation, the average contact stress and elastic approach of the inner and outer rings are less than their upper limit contact stress and upper limit approach. Time has proved that this installation method does not damage the steel ball and the ferrule.

The harmonic reducer flexible bearing installation process

1. First fix the inner ring and the steel ball, align the steel ball with the inner ring channel and fix the position, and put the steel ball to one side first.

2. Put the outer ring into the outer ring, and the channel on one side of the outer ring is also aligned with the steel ball. At this time, the outer ring is placed obliquely, and a gland is placed on the outer ring to facilitate the application of force.

3. Gradually increase the pressure, so that the steel ball will enter the outer ring channel in sequence until it is completed.

4. When the outer ring is stretched and deformed, the steel ball will give a tension to the outer ring, and at the same time the outer ring is pressed down, and the steel ball and the outer ring rib rub into the channel.

5. In order to prevent damage to the steel ball, it is necessary to grind the inner diameter of the outer ring, and attach the inner and outer rings to be strung lightly, so that there is no damage to the ferrule and the steel ball.

The above is the whole content of the installation method and process of the flexible bearing of the harmonic reducer. After the above introduction, it can be seen that the assembly methods of the flexible bearing of the harmonic reducer mainly include the conventional ball filling method, the arc ball filling groove method, the fracture ball filling method, and the elastic filling method. Under normal circumstances, elastic filling is used, but a certain assembly mold is required to cooperate, so the design of the assembly mold is equally important.