New Engine Torque Sensor Boosts Fuel Economy, Expands Mobility Safety

NSK Ltd., which operates its U.S. sales office in Ann Arbor, today announced it has developed a vehicle torque sensor that measures drive shaft torque in real time, the first in the world with this capability.
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NSK's torque sensor
NSK’s vehicle torque sensor measures drive shaft torque in real time. // Image courtesy of NSK Ltd.

NSK Ltd., which operates its U.S. sales office in Ann Arbor, today announced it has developed a vehicle torque sensor that measures drive shaft torque in real time, the first in the world with this capability.

The company states the sensor can increase fuel economy, improve ride comfort and safety, and expand a world of new possibilities across CASE (Connected, Autonomous, Shared and Services, Electric).

The sensor uses magnetic fields to detect torque by measuring minute twisting of the drive shaft that occurs naturally as it is rotated by the motor. Conventional torque sensors have been too complicated or expensive for wide scale use, but NSK’s new technology makes it possible to have a simple structure in a compact sensor that is ideal for mass production and broad adoption by automakers.

A significant benefit of the new torque sensor is increased fuel economy through reduced power consumption, and improved ride comfort and safety.

The automotive industry is currently amid a once-in-a-century period of profound transformation centered around mobility services. The car of the near future is expected to maximize safety and comfort and reduce environmental impact.

To realize the potential, vehicles must be equipped with various sensors to accurately understand the state of the vehicle to execute advanced control methods. NSK’s non-contact drive shaft torque sensor is an industry first.

The drive shaft is a key component that is used to transmit the power of the engine or motor to the wheels. Measuring torque at the drive shaft provides vital information that can be used to increase fuel economy, improve comfort and safety, reduce environmental impact, and even detect abnormalities or malfunctions in the vehicle.

Until the introduction of NSK’s new product, however, conventional torque sensors were too large and too complicated to be suitable for mass production vehicles.

Product features include:

Non-Contact Sensor

  • Achieved a non-contact design with a simple structure ideal for mass production.
  • High reliability due to no friction occurring between the sensor and the shaft.

Compact

  • Reduced the width of the unit by half and improved sensitivity by using a special method of wrapping the sensor coil and employing an optimized material.

Ease of Manufacturing

  • The sensor requires no grooves, coatings, or other special processing of the shaft.
  • Only requires shaft materials and basic surface processing methods that have a history of use in mass-production car models.

Customer Benefits

Better Fuel Economy (Lower Power Consumption).

The concept of pairing electric motor with two-speed transmission in EV is gaining attention as an effective method to deliver increased efficiency. NSK’s torque sensor can help deliver shock-free gear shifting enabling the use of a larger step ratio to deliver 7 percent increased fuel economy. In belt-driven CVT systems, data from NSK’s torque sensor can help to adjust and reduce the hydraulic clamping force applied to the belt to the minimum required, thereby reducing transmission loss for a 1.05 percent increase in fuel economy.

Increased Comfort

The torque sensor can be used to achieve a smoother ride through advanced control that softens fluctuations in torque when changing gears and accelerating/decelerating.

Identify Abnormalities

By continuously monitoring and tracking torque, it is possible to predict and identify issues and abnormalities in the vehicle at an early stage before they develop into larger problems.

Connected

As always-online vehicles become the norm, the data gathered by the sensor can be used to identify the state of nearby vehicles, and can be shared and analyzed to identify collective road usage patterns and deliver new value to society.

NSK began manufacturing the first bearings in Japan in 1916, and has since developed into a global organization researching, designing, and manufacturing Motion & Control solutions essential for mobility and industrial applications. NSK is the top supplier of bearings in Japan and is the third largest supplier in the world by market share.

The company’s products and technologies enhance automotive performance and industrial productivity while reducing energy consumption. It operates more than 200 business locations in 30 countries along with several joint ventures and partnerships.