Helps to reduce the size and power consumption of electric actuators in various fields such as automobiles and industrial machinery

NSK has achieved high transmission efficiency and reliable locking function through long-term accumulated friction control technology, without consuming electricity.

When installed on the rear wheel steering actuator of a car, the transmission efficiency from the motor to the tires is increased by about 70% compared to traditional systems, and it also has self-locking function, which will not transmit external force to the motor. This allows the size of the actuator motor to be reduced by about 40% compared to traditional motors, which helps to reduce power consumption.

It can be widely applied in other automotive application fields (such as vehicle height adjustment, electric doors and seats, etc.), parking mechanisms, lifting devices of AGVs and transport robots, and other industrial machinery fields.

NSK has successfully developed a high-efficiency, zero power consumption lockup clutch, contributing to the miniaturization and low power consumption of electric actuators in a wide range of fields such as automobiles and industrial machinery.

The product developed this time will be launched to the market after being evaluated by customer samples, and is expected to achieve sales of 3 billion yen by 2030.

The development product 'Lock up Clutch' this time

Development background

1) Requirement for rear wheel steering actuator

With the popularization of electric vehicles and autonomous driving, the demand for high-precision automatic control of rear wheel motion for rear wheel steering actuators is also constantly increasing. The rear wheel steering actuator can improve vehicle safety and ride comfort. In addition, by reducing the turning radius of the vehicle, the wheelbase can be extended, allowing for the installation of more batteries in this space, which helps to extend the range of electric vehicles.

Rear wheel steering actuator for high-precision control of rear wheel motion

2) Function of rear wheel steering actuator

Generally speaking, traditional rear wheel steering actuators use trapezoidal lead screws and utilize their performance to achieve the following two functions.

(1) Drive function: Transmit the power of the motor to the tire (convert the motor's rotational motion into linear motion through a trapezoidal screw, thereby controlling the tire's motion).

(2) Position retention function: With self-locking function, it can prevent external force from being transmitted to the motor (through the self-locking function of the trapezoidal screw, it can prevent the force accidentally transmitted from the road surface to the tire from being transmitted to the motor).

Drive function (left) and position holding function (right) of rear wheel steering actuator

3) The problem of rear wheel steering actuator

There is a problem of low power transmission efficiency when using a trapezoidal lead screw rear wheel steering actuator to transmit power from the motor to the tires. When using ball screws with high transmission efficiency instead of trapezoidal screws to solve this problem, the lack of self-locking function in ball screws can result in power consumption during position maintenance.

4) Solution to the problem of rear wheel steering actuator

By developing a self-locking lock up clutch and combining it with a ball screw with high transmission efficiency, the transmission efficiency of the rear wheel steering actuator can be improved, and the position holding function can be achieved. Thus solving the above-mentioned problems.

                                                                                                                             Overview of the development product

Lock up clutch is a new type of power flow control clutch that can transmit the rotation of the input shaft and lock the rotation from the output shaft.

The rotation of the input shaft is transmitted (left), and the rotation from the output shaft is locked (right)

Installation position of this development product in the rear wheel steering actuator

                                                                                                                     Advantages of Development Products

1) High transmission efficiency and position retention function

NSK has achieved high transmission efficiency and reliable locking function through long-term accumulated friction control technology, without the need for electricity.

2) Contribute to the miniaturization and low power consumption of rear wheel steering actuators

The newly developed product, when used in conjunction with ball screws, can improve the transmission efficiency of the rear wheel steering actuator (by about 70% compared to traditional products) and provide self-locking function when maintaining position.

This enables the motor of the rear wheel steering actuator to be miniaturized (reduced by about 40% compared to traditional motors), which helps to reduce power consumption.

3) Contribute to a wide range of industries from automobiles to industrial machinery

In the new lubrication mechanism, the improved oil supply seat can directly supply oil to the inside of the bearing, requiring only a small amount of lubricating oil through the action of centrifugal force. Reducing lubricant usage and power loss while maintaining high usability and low cost.

This product can be applied not only to the rear wheel steering actuator of automobiles, but also to many other fields.

*Example of application installation:

• Automobile:

Vehicle height adjustment, electric doors, electric seats, power switching clutch

Industrial machinery:

Electrification of hydraulic and pneumatic equipment such as parking mechanisms, lifting devices, robotic arms, electric cylinders, etc. for AGVs and automatic transport robots

The information contained in the press release is the latest as of the date of publication.

Please note that information is subject to change without prior notice and may differ from the information at the time of publication.