Enhancing eDrive Shift-by-Wire Actuation with Syensqo’s Ryton? PPS: Unmatched Thermal Stability, Electrical Resistance, and Laser Weldability

By Joerg Ewering, Bill Sattich, Luigi Marino, Yasu Sato, Greg Poterala, Alyssa Arend, Brian Baleno

Syensqo Materials

Electric drive system engineers working on battery electric vehicle (BEV) powertrains are striving to achieve higher efficiency, increased torque performance, and reduced noise, vibration, and harshness (NVH). Shift-by-wire electric actuators play an important role in addressing these design challenges. The primary function of a shift-by-wire actuator is to improve electromechanical shifting by transmitting the driver's signal from the electric control unit to the electric driver's transmission, often using a BLDC motor.

To optimize actuator performance, thermoplastics, and Ryton? PPS in particular, can contribute to light-weighting by replacing metal housings, reducing NVH, and also packaging with smaller and more compact designs. Some of the key benefits of Ryton? XE4050BL for actuator housings include high temperature resistance, dimensional stability and electrical performance. Figure 1 below shows the superior tensile strength retention of Ryton? PPS over nylon PA66.

Figure 1: Tensile Strength Aging comparing PPS to PA66

Maintaining tight tolerances after injection molding and dimensional stability are also important considerations for electric actuators. Ryton? PPS provides excellent dimensional stability even when exposed to eDrive fluids such as oils. Figure 2 shows the dimensional stability of Ryton? XE4050BL over 1000 hours at 150 ℃.

Figure 2: Dimensional Stability after 1000 hours of Oil (Dextron VI ATF)

One of the key factors driving the use of Ryton? PPS XE4050BL in shift-by-wire actuators is the electrical properties and flammability rating. The electrical properties are shown in Table 1 below.

Table 1: Ryton? PPS XE4050BL Electrical Properties

Finally, Ryton? PPS can be laser welded, allowing for the electrical actuator sensor to be welded to the housing. Laser welding technology is one of the techniques used to join together several different polymer components. The process gives engineers with greater degrees of design freedom while producing clean robust connections.?

Ryton? R-3-410BL LZT is a 30% glass fiber filled PPS developed for laser welding to other Ryton? PPS grades. Table 2 summarizes the mechanical properties of Ryton? R-3-410BL LZT.

Table 2: Ryton? PPS R-3-410 BL LZT Overview

In conclusion, Syensqo’s Ryton? XE4050BL and R-3-410BL LZT can be considered for shift-by-wire electrical actuator housings and sensors. The combination of these two solutions can lead to weight savings, more compact design, and also reduced NVH.