Electric Gripper With Voice-Coil Drive for Compact Force Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional grippers with motors for small clamping forces face challenges in miniaturization and accurate position and force control due to their large volume.
Innovation Solution
An electric gripper utilizing a voice coil motor and dual-lever assemblies in a staggered arrangement, with an angle sensor and force sensor, enabling precise position and force control, and a self-locking mechanism for enhanced reliability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If conventional stepping motor or DC motor is used in the gripper, then the driving function is achieved, but the volume becomes large and cannot be miniaturized
Solution Approach 1:
The patent replaces conventional motors (stepping motor or DC motor) with a voice coil motor, which uses electromagnetic force directly to drive the sliding portion without traditional mechanical components like shafts and gears. This substitution enables miniaturization while maintaining driving functionality
Solution Approach 2:
The patent changes the driving mechanism from rotational motor output to linear electromagnetic force output. The voice coil motor converts electrical current directly into linear displacement of the sliding portion, fundamentally changing the motion parameter from rotational to linear, which enables compact design
2Measurement precision
If conventional motor is used, then driving capability is provided, but position and force control accuracy cannot be achieved
Solution Approach 1:
The patent incorporates an angle sensor that detects the rotation angle of the drive lever and provides feedback to the control unit. The control unit calculates the displacement amount of the sliding portion based on the detected angle, enabling precise position control through closed-loop feedback
Solution Approach 2:
The voice coil motor inherently provides precise position control through its electromagnetic mechanism. The direct conversion of electrical current to linear displacement without mechanical transmission components eliminates backslash and reduces control complexity while maintaining high precision
3Force
If conventional motor is used, then driving function is achieved, but force control cannot be realized
Solution Approach 1:
The patent incorporates a force sensor that detects the clamping force applied by the gripping pieces and provides feedback to the control unit. This enables the control unit to adjust the driving current to the voice coil motor to maintain precise force control
Solution Approach 2:
The voice coil motor's electromagnetic force generation allows direct force control through current adjustment. The motor can maintain constant force output by simply controlling the electrical current, eliminating the need for complex mechanical force multiplication mechanisms
4Length of moving object
If dual-lever assemblies are arranged in staggered configuration, then thin design is achieved, but structural complexity increases
Solution Approach 1:
The patent transitions from a single-plane lever arrangement to a staggered three-dimensional configuration. The drive lever and resistance lever are arranged at different positions and angles, creating a compact spatial structure that reduces the overall thickness while distributing mechanical stresses more efficiently
Solution Approach 2:
The dual-lever assemblies are arranged in a nested staggered configuration where the drive lever and resistance lever interleave in space. This nesting arrangement allows both levers to occupy overlapping spatial zones, minimizing the overall footprint and thickness of the gripper mechanism
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The gripper achieves miniaturization, low cost, fast response, and high precision with stable torque and force control, suitable for applications requiring small clamping forces.
Implementation Method 1
a voice coil motor (VCM) is served as a driving device in the electric gripper
Implementation Method 2
the relative displacement and rotation relationship between the driver and the two dual-lever assemblies are sensed through the sensing element to sense the distance and the angle
Implementation Method 3
a self-locking function is achieved through a spring
Data Source
AI summary
An electric gripper is disclosed and includes a carrier, an actuator, two dual-lever assemblies and an angle sensor. The actuator is disposed on the carrier and includes a sliding portion. The two dual-lever assemblies are disposed on the carrier and located at two opposite lateral sides of the sliding portion. Each of the two dual-lever assemblies includes a driving lever, a limiting lever and a gripping piece. The driving levers are staggered to each other. The limiting levers are staggered to each other. When the sliding portion slides a first distance in the first direction, the sliding portion drives the driving levers to rotate an angle, and the gripping pieces move toward each other to displace a second distance in a second direction. The angle sensor is disposed on the carrier and configured to measure the angle, to correspond to the first distance and the second distance.