From QF to VGTH: An Overview of W-Robot Linear Module Families

1. The big picture: how W-Robot linear modules are organised

From a drive-type perspective, W-Robot linear modules can first be grouped into three main categories:

Ball screw linear module series
Typical families: QF, VETH, VF, VC, VGTH, VGTY, VGTYD, VZ

Timing belt linear module series
Typical families: OB, EB, VBF, VBC, VGTB, LB

Other motion solutions (rack & pinion, linear motors, multi-axis stages, electric cylinders, etc.)

In this article we focus on the first two, because they form the core of the W-Robot linear module offering used in many automation machines.

A simple way to think about it:

If your priority is precision, stiffness, repeatability with moderate stroke and speed → look at the ball screw linear module series.

If your priority is long stroke, high speed, frequent shuttling → look at the timing belt linear module families.

Within each group, different series are tuned for different space constraints, load levels, and environmental conditions.

2. Ball screw linear module series: from QF to VGTH

2.1 QF Series – ultra-thin ball screw modules for compact machines

The QF Series is often the first contact point for new W-Robot users, especially in 3C and small equipment:

Key idea: ultra-thin, space-saving ball screw linear module

Typical characteristics:

Very slim cross-section

Low overall height

Short to medium stroke range

Where it fits best:

Compact 3C electronics equipment

Small vision inspection stages

Measurement or testing fixtures where the module must fit into a tight envelope

If your design notes say things like “space is tight, stroke is not very long, the axis needs to be as thin as possible”, then the QF family is usually the right place to start within the W-Robot linear module catalog.

2.2 VETH Series – general-purpose ball screw modules

The VETH Series can be viewed as a general-purpose workhorse in the W-Robot ball screw linear module series:

Designed for a wide range of standard automation equipment

Broad stroke coverage

Balanced performance in load capacity, stiffness, and size

Typical applications:

Pick-and-place units on assembly lines

X/Y axes of vision positioning platforms

General inspection equipment and loading/unloading axes

If your application does not have extreme space, load, or environmental demands and you want a dependable, easy-to-select axis, the VETH Series is usually a good starting point.

2.3 VF & VC Series – high-rigidity, heavy-load ball screw modules

Moving up in robustness, VF and VC families are designed for high rigidity and heavy loads:

Reinforced body structures

Strong resistance to torque and bending

Suitable for larger payloads and off-centre loads

Typical applications:

Loading and unloading for CNC machines and machining centres

Handling heavy fixtures, jigs, or large workpieces

Main axes in dual-axis or gantry structures where stiffness is crucial

If your calculations show higher payloads and large moments, or you are working near cutting forces and heavy tooling, the VF/VC ball screw linear module series will usually be more appropriate than lighter families.

2.4 VGTH Series – enclosed ball screw modules for harsh environments

The VGTH Series is often highlighted in W-Robot case studies because it solves a very common real-world problem:

How to keep a ball screw linear module running reliably in the presence of dust, chips, coolant, and oil mist?

Key characteristics of VGTH:

Semi-enclosed or fully-enclosed structure

Covers and seals that isolate screw and guides from the outside environment

Designed to maintain performance and reduce contamination-related maintenance

Typical applications:

Loading/unloading and transfer axes around metal cutting and grinding machines

Battery production lines and photovoltaic module production, where dust and particles are common

Production lines that must run for long periods between maintenance intervals

If your factory environment is far from clean and you need a ball screw linear module that can cope with dust, chips, or coolant, the VGTH family is often the right direction rather than an open-type screw module.

2.5 VGTY / VGTYD / VZ – electric-cylinder-type ball screw modules

Alongside standard linear modules, W-Robot offers families that feel closer to electric cylinders or integrated actuators:

VGTY / VGTYD Series

Higher integration of ball screw, guide, and motor interface

Suitable for electric-cylinder-style applications

VZ Series

Electric cylinder products for controlled push-pull motion

Typical use cases:

Replacing pneumatic cylinders with position-controlled electric actuators

Applications that need controlled stroke, speed, and force in a compact actuator body

Press-fit, lifting, and push-pull mechanisms where repeatability and adjustability matter

These families are useful when you want the control benefits of a ball screw linear module, but in a form factor and mounting style that is closer to a traditional cylinder.

3. Timing belt linear module families: OB, EB, VBF, VBC, VGTB

When your keywords become “long stroke”, “high speed”, and “frequent shuttling between stations”, most solutions will come from the timing belt linear module side of the W-Robot portfolio.

3.1 OB Series – high-speed belt modules for long transfer

The OB Series is aimed at high-speed transfer over long distances:

Suitable for strokes of 1–3 metres or more

Designed for fast moves between upstream and downstream stations

Used where extreme positioning accuracy is not the primary focus, but speed and throughput are

Typical applications:

Part transfer in logistics and sorting lines

Long-distance transfer axes in battery, PV, and electronics production

Movement between multiple workstations on assembly lines

If your system is more about “move parts quickly from station A to station B” than about “micron-level positioning within a small working area”, an OB timing belt linear module is often a better fit than a long ball screw axis.

3.2 EB Series – universal timing belt linear modules

The EB Series can be considered the general-purpose equivalent on the timing belt linear module side, similar to how VETH functions on the ball screw side:

Balanced design for speed, stroke, and compactness

Frequently used in small and medium-sized equipment

Suitable for light to medium payload transfer

Typical applications:

Transfer between stations on compact automation equipment

Inspection and testing machines needing fast but moderate-precision positioning

General light-duty handling axes

If you need a standard W-Robot linear module with belt drive and you do not have extreme requirements, the EB Series is usually a good candidate.

3.3 VBF & LB Series – belt stages for general environments

VBF and LB series typically appear in general-environment transfer and handling tasks:

Robust designs for everyday handling applications

Multiple mounting options

Suitable for many standard production line tasks with moderate environmental demands

They can be used where you have neither aggressive contamination nor cleanroom-level constraints, and simply need reliable belt-driven linear motion.

3.4 VBC Series – for cleaner or controlled environments

Where particle control and cleanliness are more important, the VBC Series comes into play:

Designed for environments with stricter contamination limits

Appropriate for cleaner manufacturing areas

Typical applications:

Certain semiconductor-related processes

Precision electronics production and inspection stations

Applications where belt-driven motion is needed but particle generation must be controlled

3.5 VGTB Series – belt modules with built-in linear guides

The VGTB Series features belt modules with integrated linear guides:

Drive and guidance combined in a compact cross-section

Simplifies mechanical design of multi-axis frames

Often used in XY stages and light gantry systems

When you want a clean, compact structure where one profile carries both the guide and the drive, the VGTB timing belt linear module can significantly simplify your machine layout.

4. A simple roadmap for first-time W-Robot users

For engineers who are new to the W-Robot linear module range, it helps to follow a short checklist before diving into each catalog page.

Ask yourself these questions:

Is installation space very limited?

Yes → Start with QF Series and other compact ball screw linear module families.

Do you have high loads or strict stiffness requirements?

Yes → Look at VF / VC Series and larger VGTH models in the ball screw family.

Is the environment dusty, oily, or full of chips and coolant?

Yes → Focus on VGTH Series and other enclosed ball screw linear module series.

Is the stroke long and the required speed high?

Yes → Explore OB, EB, VBF, VGTB and related timing belt linear module families.

Do you want a form factor similar to an electric cylinder?

Yes → Consider VGTY / VGTYD / VZ actuator-type ball screw modules.

Once you answer these questions, you can usually narrow your search down to two or three families. From there, you simply compare:

Stroke range

Load and moment ratings

Repeatability

Mounting patterns

Environmental options

instead of trying to understand every product code at the same time.

5. What to do next

If you are at the stage of selecting your first W-Robot linear module, a practical next step is:

Write down your key requirements clearly:

Stroke

Load and moments

Required speed and cycle time

Environmental conditions

Space constraints

Use the “roadmap” above to identify the most relevant ball screw linear module series or timing belt linear module families.

Open the corresponding W-Robot product pages and catalogs to choose the exact size and stroke.

By approaching the W-Robot portfolio family by family—from QF and VETH up to VGTH, and from OB and EB to VGTB—you can move from confusion to a clear, structured short list in just a few steps, and focus your time on the detailed engineering rather than decoding product names.