The SMC MSQB20A is a compact rotary table from SMC’s MSQ Series, officially classified as a Rack & Pinion Style, MSQB Basic Type model. In SMC’s naming structure, the size is 20, and the suffix A indicates the version with adjustment bolt. The official web catalog also identifies this model as a design that integrates a table and a rotary actuator, includes an angle adjustment mechanism, and is intended for easy alignment when mounting the load and the body.
In practical terms, the MSQB20A is designed for equipment that needs a mounted workpiece, fixture, or small mechanism to rotate to a controlled position rather than simply oscillate on a shaft. Because the rotating table is built into the actuator body, the unit can simplify mechanical design, reduce alignment work, and provide a cleaner solution for compact automation equipment. That makes it well suited to indexing, part turning, orientation, and transfer tasks in pneumatic systems where reliability and installation efficiency matter.
Key Specifications
| Item | Description |
|---|---|
| Brand | SMC |
| Model | MSQB20A |
| Product Category | Rotary Table |
| Series | MSQ Series |
| Structure | Rack & Pinion Style |
| Type | MSQB Basic Type |
| Size | 20 |
| Suffix Meaning | With Adjustment Bolt |
| Operating Fluid | Air (non-lube) |
| Maximum Operating Pressure | 1 MPa |
| Minimum Operating Pressure | 0.1 MPa |
| Ambient / Fluid Temperature | 0 to 60°C, no freezing |
| Angle Adjustment Range | 0 to 190° |
| Maximum Rotation | 190° |
| Cylinder Bore Size | Ø18 mm |
| Port Size | M5 x 0.8 |
| Auto Switch Configuration | Without auto switch, built-in magnet |
| Number of Auto Switches | 2 pcs. or none |
| Product Net Weight | 939 g |
| Weight Note | Auto switch weight not included |
| Adjustment Angle per One Rotation of Adjustment Screw | 7.2° |
| Rotation Direction | A port: clockwise; B port: counter-clockwise |
The specification summary above is compiled from SMC’s official web catalog and the MSQ series documentation for the basic type and size 20 configuration.
Compact Rotary Table Design for Machine Builders
A major advantage of the MSQB20A is that it is not just a rotary actuator in the narrow sense. SMC explicitly describes the MSQ design as an integration of a table and a rotary actuator, which is important from an engineering point of view. In many machines, using separate brackets, couplings, and rotary mechanisms increases installation time and introduces more alignment variables. By combining the rotary drive and the mounting table in one body, the MSQB20A helps reduce these complications. For machine builders, that usually means a more compact structure, fewer assembly steps, and better consistency from one machine build to the next.
The MSQB20A is also part of the basic type within the MSQ family, so it is aimed at applications where a practical and robust rotary table is needed without moving to the heavier high-precision variant. That distinction matters when balancing cost, footprint, and performance. In many automation systems, especially compact assembly tools and handling devices, the basic type is the more efficient choice because it delivers the required rotary motion while keeping the unit smaller and lighter than more specialized alternatives.
Flexible Rotation and Adjustment Capability
One of the defining functional features of the MSQB20A is its adjustable rotation range. According to the official MSQ documentation, the model supports an angle adjustment range of 0 to 190°, with a maximum rotation of 190°. For designers, this is more useful than a fixed-angle device because the final stop position can be adapted to the actual fixture geometry and process requirement. Instead of designing the machine around a rigid rotary angle, the machine can be tuned around the application.
SMC also provides a practical adjustment reference for the size 20 version: the adjustment angle per one rotation of the angle adjustment screw is 7.2°. This is a useful engineering detail because it gives a predictable relationship between screw adjustment and rotary end position. In real installation work, that makes setup easier, especially when fine-tuning the turn angle for pick-and-place, part presentation, inspection alignment, or small assembly fixtures.
The official series documentation further states that the rotary table turns clockwise when the A port is pressurized and counter-clockwise when the B port is pressurized. This straightforward directional logic supports clean pneumatic control design and makes the MSQB20A easy to integrate into standard valve-controlled motion circuits. For system designers, clear direction mapping reduces commissioning errors and simplifies troubleshooting later in the machine life cycle.
Pneumatic Performance and Installation Suitability
For operating conditions, the MSQB20A uses air (non-lube) as its working medium. The official documentation lists a maximum operating pressure of 1 MPa and a minimum operating pressure of 0.1 MPa for the adjustment-bolt type. The specified ambient and fluid temperature range is 0 to 60°C without freezing. These are mainstream industrial pneumatic values, which means the unit can be integrated into many standard compressed-air systems without unusual support requirements.
The cylinder bore size is Ø18 mm, and the port size for size 20 is M5 x 0.8. That places the MSQB20A firmly in the compact rotary table category. It is not intended for very large workholding loads, but it is highly relevant for small and medium automation modules where space is limited and rotary positioning is needed at moderate load levels. The compact porting and body format also make it a practical option for bench-top equipment, semiconductor-related tooling, packaging modules, sensor positioning devices, and other machinery where installation space is limited.
Product Weight and Mechanical Planning
For many buyers, the product weight is not a minor detail. It affects bracket design, moving-axis load calculations, support stiffness, shipping estimates, and the overall feel of the machine module. SMC’s official MSQ documentation lists the basic type, size 20, with adjustment bolt at 939 g, and it specifically notes that the published value does not include auto switch weight. This means the core actuator-table body is just under one kilogram, which is a favorable balance for compact industrial equipment: substantial enough to feel mechanically solid, yet still light enough for many small automated assemblies and fixtures.
From a design perspective, a 939 g rotary table is often easier to mount and support than larger indexing units, especially when the surrounding frame is aluminum profile, thin plate, or compact machined structure. It also makes the MSQB20A attractive where multiple actuators are used in one machine and total moving mass must be controlled. In short, the weight profile supports its role as a practical compact automation component rather than a heavy-duty rotary platform.
Sensor Preparation and Configuration Flexibility
The official web catalog shows that the MSQB20A is supplied without auto switch, but it has a built-in magnet, and the switch configuration is listed as 2 pcs. or none. This is a useful arrangement because it gives buyers flexibility. A simpler machine can use the product without switches, while an OEM or integrator who needs position confirmation can build around the magnet-ready configuration and add the appropriate sensing arrangement as required.
This flexibility is important in real projects because not every application needs the same level of feedback. Some rotary operations rely purely on pneumatic timing and mechanical end positions, while others require confirmation signals for PLC logic, sequencing, or safety interlocks. By starting with a built-in magnet but no standard switch, the MSQB20A leaves room for different machine architectures without forcing unnecessary hardware into every installation.
Typical Industrial Uses
Although SMC’s catalog focuses on product structure and technical data rather than long marketing narratives, the engineering profile of the MSQB20A makes its application range fairly clear. A compact rotary table with an integrated mounting surface, adjustable angle, and standard pneumatic control is well suited to part orientation, small fixture indexing, transfer positioning, inspection-angle adjustment, and assembly station rotation. These are logical use cases based on the product’s official table-integrated design, adjustable rotation mechanism, compact size, and defined directional control.
For example, in a small automated assembly cell, the MSQB20A can rotate a component from a loading position to a fastening or inspection position. In a test fixture, it can turn a part to present a second face to a sensor or probe. In packaging or labeling equipment, it can help reposition a product or tooling head within a compact motion envelope. The value here is not just rotation, but controlled and mountable rotation in a compact pneumatic package.
Conclusion
The SMC MSQB20A is a compact and practical MSQ Series rotary table built for machine designers who need controlled pneumatic rotary motion with direct load mounting. Officially, it is a Rack & Pinion Style, MSQB Basic Type, size 20, with adjustment bolt. Its key strengths include integrated table-and-actuator construction, easy mounting alignment, 0 to 190° angle adjustment range, 190° maximum rotation, Ø18 mm bore size, M5 x 0.8 port size, built-in magnet, and an official product mass of 940 g excluding auto switch weight. For automation equipment that needs a clean, compact, and adjustable rotary positioning unit, the MSQB20A is a well-defined and technically credible option within the SMC lineup.
