Types of joints in a chain

TYPES OF JOINTS IN A CHAIN

The general types of joints in a chain are shown in Fig. 1.20.

1. Binary Joint

• If two links are joined at the same connection, the joint is known as binary joint.

• For example, a kinematic chain shown in Fig.1.21, has four binary joints at A, B, C and D.

2. Ternary Joint

• If three links are joined at the same connection, the joint is known as ternary joint.

• For example, a kinematic chain shown in Fig.1.22, has three binary joints at A, B and E, and two ternary joints at C and D.

• One ternary joint is equivalent to two binary joints.

• The equivalent number of binary joints for the chain shown in Fig.1.22, is given by

3. Quaternary Joint

• If four links are joined at the same connection, the joint is known as quaternary joint.

• For example, a kinematic chain shown in Fig.1.23, has one binary joint at C, four ternary joints at A, B, D and E, and two quaternary joints at F and G.

• One quaternary joint is equivalent to three binary joints.

• The equivalent number of binary joints for the chain shown in Fig. 1.23, is given by