Method for forming cross slider coupling

　　By replacing the two rotary joints B and C of the connecting rod with two translational joints of the Oldham slider coupling, you can see the structure of Adam (Oldham) composed of 4 flat hinge stitches.At that time, the general structure of the Oldham coupling consisted of three dynamic stages, two cranks and X stitches.

　　The typical parameters of this structure are:

　　a: The distance from the rotation center A to the sliding center line B.

　　b: The distance from the rotation center D to the sliding center line C.

　　d: The distance of D between the two middle A.

　　α: The angle between the middle line sliding joints B and C. α cannot be 0 degrees, because then the crank cannot rotate.

　　In fact, a = b = 0 is common; α = 90 degrees, called the standard Adam structure.

　　2. Kinematic characteristics of cross slide coupling

　　The two cranks rotate the entire round.

　　The angular velocity of the two cranks and the X-shaped needle is always the same.

　　The trajectory of the X-shaped stitch is shown in Figure 2.

　　Please note that the crank rotates once and point A moves along the circle (red) twice.In the case of standard Adam, point A is the intersection of the two sliding middle lines of the X needle, and the center of the circle is the midpoint of the line connecting the two rotary joints