The constant speed universal joint is an indispensable part in the chassis transmission system. Through the completely uniform rotation movement of the two axles, it can avoid the "pumping" of the vehicle, will not cause unnecessary pressure to other related parts, and plays an important role in driving safety.

So, do you know exactly how it actually works? This article will explain to you in detail through 5 groups of questions and answers.

1. What are the structural characteristics of the constant-velocity universal joints?

The structure of the constant universal joint at first glance some complex —— consists of ball, ball fairway and holder. Close inspection, however, reveals the ingenious design of transferring the rotational motion evenly from the drive axis to the output axis. There are many designs of these parts, but this structure is the most common:

One end of the shaft has a cup device with grooves inside;

At the other end of the shaft has a coronal head with an external groove;

Both parts are gear profiles, and the groove allows the shaft to bend smoothly while transferring power.

Generally applicable for uniform power transmission: isokinetic universal joint

2. Who invented the constant-speed universal joint?

It is not uncommon to transfer rotational motion between two axes at certain angles. One of the earliest solutions was the universal festival invented by Grolamo-Cadadano (Gerolamo Cardano) in the 16th century. The universal axis named in his name uses this universal joint, but it has a decisive drawback: the larger the articulation Angle, the more uneven the power transmission is.

The universal universal festival is the predecessor of the instant universal one

In 1926, Jean-Albert-Greguire (Jean Albert Gregoire) and Pierre-Fainer (Pierre Fenaille) developed an angle-free error drive, the first isokinetic universal joint with a fork in the joint. Tracta It was used in the first batch of front-drive cars. To this day, some experts will still call them "Tracta joints".

Two years later, Ford developed the shapes still most commonly used, including spherical joints.

Is the whole device of the constant-speed universal joint very sensitive?

Is obvious: small structures with grooves and balls must not be dirty. Therefore, the whole device is usually surrounded by rubber shaft sleeves, which are clearly visible on the inside of the wheel. Also, the whole unit shall be lubricated with grease package.

4. Do the constant-speed universal joints need maintenance?

This should be a surprising fact: universal usually do not require repair. Auto Shop experts usually just check whether the outer sleeve is broken. Of course, the Halloween inner grease is not permanent, but according to the condition of the Halloween grease, it can also be "pressed into" from the outside.

5. What do these characteristics of the constant-speed universal node mean for its industrial production?

The interaction between the ball groove (a roller channel) and the ball is physically complex. The force is used in all directions, so that the fairway is millimeter-level and accurate, as is the journal and holder.