The principles of linear motion have been understood by one and all and has seen many physicists regarding the laws written down as holy grail, propounding on force mass and acceleration. The linear actuators have revolutionized the manual way of doing things into automation where the vital component in the unit is actuators. Right from cupboards and automatic windows to heavy duty conveyors and fork-lifts, electric linear actuators find importance in every product. There are actuators of various sizes, strokes and speeds. The Actuators come across many names such as single axis actuator that moves load along one axis. Linear actuators come in many shapes and sizes and these are a few of the agendas that need to be taken care of while picking up an actuator.
Simple Stage Actuator Systems
Basic stages systems occur in electric , manual and pneumatic versions. Pneumatic and electric versions can be used in both vertical and horizontal position for conveyance and work transfers or other motions.
In selecting linear actuators, you can narrow down asking features to weight of the load to be transported, length of stroke, travel speed and accuracy demands and ambient operating environment.
Some of the actuators can be configured with standard or custom mounting brackets and angle plates to form X/Y or X/Z or X/Y/Z axes. Common application areas suggest servo-driven insertion and drilling, precision measurement, QC ,testing and Inspection, pick and place tables and painting stations.
When high precision application is demanded, actuators with calibration system should be provided. Limit switches and end-of-travel switches are also provided along with actuators to help with certain functions.
Belt Drive Actuators:
They come in a wide array of lengths and offer a versatile choice for perfect use in diverse applications in many industries including packaging, printing, machine tool, aerospace and defense. The exact uses depend upon precision-machined steel construction, an interior shaft for supreme strength and an ultra tough timing belt.
Keep the following basic points as important guidelines to make right selection of actuators-: Ask yourself these questions as you go looking for that perfect actuator.
- Weight or force to move and hold the load.
- Power Supply Options: A/C or D/C motor voltage required to operate the actuator.
- Rate at which the linear actuator moves the load.
- Stroke length: Amount of travel required by the application.
- Mounting Options: Front or back mounted.
- Safety measures incorporated
Stroke Length: Is the distance that the actuator needs to move in one direction and is the first requirement in choosing between ball screw or belt drive. Ball screw actuators come at minimum lengths of 1000mm or less although 3000mm ball screws are also used. The limit is governed by screw’s critical speed.
Speed: The second critical factor in choosing an actuator is its speed. The maximum speed for most belt drives is 5 m/s and this limit is governed by the guide system which commonly uses recirculating bearings.
Accuracy: Is the term used to designate travel accuracy or positioning accuracy. Positioning accuracy is how closely the actuator reaches the target position. Travel accuracy is heavily dependant upon structure, base and mounting while Positioning Accuracy is dependant upon drive mechanism.