Contents
MINI
Basics
1. How does a MINI work?
A MINI cylinder combines the well-known principles of electromechanical linear drive systems in a compact housing. The rotational movement of the integrated motor turns a spindle, which in turn causes an axial movement of the bronze nut mounted on it. A piston rod is mounted on the nut, which then performs the lifting movement outside the cylinder housing.
A distinctive feature of the MINI is the hollow shaft technology of the motor. An axial bore through the entire motor package allows for the integration of the spindle and nut within the motor, thus shortening the overall length of the cylinder compared to conventional cylinders where the motor occupies additional space.
For the MINI0 size, an AC motor 1x230V and a DC motor 24VDC are available. All other sizes are powered by AC or three-phase motors.
Hollow shaft motor inside the MINI
2. Sizes and options
The MINI drive is available in the following sizes:
- MINI0
- MINI01
- MINI1
- MINI2
- MINI3
These sizes cover a load range from 1000 N to 26,000 N. The drives can be equipped with various attachments such as spherical heads, rod end bearings, swivel pins, mounting feet, and mounting flanges. Additionally, integrated options such as brakes, potentiometers, encoders, limit switches, and force-dependent shutdowns can facilitate integration into automated systems.
3. Mounting an electric drive MINI
GROB Antriebstechnik GmbH
4. Everywhere included
Depending on the desired stroke speed, a planetary gearbox is integrated at the factory. Additionally, every MINI is equipped with end switches and safety switches as standard. These can be wired internally or in the control cabinet, depending on your choice. The housings are made of stainless steel for all MINI sizes up to MINI1, while MINI2 and MINI3 are always powder-coated. The piston rod is made of stainless steel in all versions.
5. When should a MINI be chosen?
Machines with limited axial space for moving parts require the shortest possible drive mechanism. This is where the MINI can be crucial in providing a solution. Its protection class (up to IP65) and high material quality (entirely stainless steel) make it suitable for use in the food industry and environments with aggressive mediums.
6. When is the MINI a poor choice?
If long strokes and high duty cycles are required, the MINI is not the right product. In standard applications, the MINI achieves up to 500 mm of stroke and up to 20% duty cycle. The fully enclosed cylinder requires sufficient cooling time to dissipate the heat generated by the integrated motor and the sliding nut.
7. Typical applications of MINIs
Medical technology
- Ventilators
- Blood pressure monitors
- Injection systems
Automation engineering
- Small robotic systems
- Assembly systems
Packaging machinery
- Small conveyor belts
- Labeling machines
- Sealing systems
Automotive engineering
- Steering systems for small vehicles
- Automated switches in vehicles
- Seat adjustments
Aerospace
- Control of miniature spacecraft
- Precision movement in satellite systems
- Instrument control
Food industry
- Dosing systems for spices and sauces
- Small conveyors for packaging
- Processing of miniature food components
Textile industry
- Control of spinning and weaving machines
- Positioning of sewing and embroidery machines
- Automated fabric handling systems
8. Pro and Cons
Cons
✘ Closed system requires longer cooling time, limiting duty cycle to a maximum of 50%
✘ Customer-side repair is only possible with considerable effort
✘ Customization is limited to certain catalog standards
Pros
✔ Suitable for applications with aggressive environmental media due to stainless steel housing
✔ Perfect for applications with limited space due to compact design
✔ Easy to clean with smooth surface
✔ Handles direct water exposure with protection rating up to IP65
✔ No maintenance intervals required due to lifetime lubrication
✔ Can be used in explosive environments (ATEX)
FAQs about MINI actuators
What are the advantages of a MINI?
- Fully made of stainless steel
- Protection rating up to IP65
- Very compact due to hollow shaft motor
Can I attach my own motor to the cylinder?
No, the MINI and linear cylinders are complete systems and cannot be expanded with other motors.
What sizes of a MINI are available?
MINI 0 (1,000 N), MINI 01 (1,600 N), MINI 1 (3,500 N), MINI 2 (14,000 N), MINI 3 (26,000 N)
How does the force-dependent shutdown work with the MINI?
Through a spring assembly, a defined force can be combined via the spring constant. When the spring assembly is compressed, a limit switch sends back the signal. Advantage: The limit switch can also be adjusted in position, allowing the customer to precisely adjust their force point.
What braking voltage do I need for the MINI?
You can choose between 24V, 230V, and 400V.
Are there also stainless steel versions available?
Yes, the use of stainless steel materials is a common practice for environments with aggressive media.
What options for spindle mounting (head variants) are available for spindle drives?
For the spindle end, the standard range offers options including threaded end, articulated head, ball joint head, flange plate, bearing flange plate, and pin. You can find corresponding dimensions in the General Catalog 2023 (grob-antriebstechnik.de)
Can the products also be used in ATEX areas?
Yes, screw jacks and MINI cylinders can be used within certain limits for ATEX zones as well.
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