CORE LINKS · DESIGN GUIDES

Move a load in a straight line

Separate the parts that support the load from the parts that drive it. Define motion and force before comparing screw and pneumatic drives.

Side-view concept: guides support the load, while the drive transmits force along the travel direction. The drawing is schematic.

What you will understand

Supporting guides versus the drive
How required thrust relates to screw torque
Component checks after estimating force

Blue: defined conditions · Red: calculated quantities. Diagrams are schematic.

m: total moving mass
s: one-way travel
F: required drive force

The examples below are illustrative. Calculator links open the normal calculator; enter the listed conditions yourself. Values are not transferred automatically.

Define the motion

Include the table and fixture in moving mass. Keep one-way travel time separate from round-trip cycle time.

Travel, one-way time, acceleration/deceleration time and dwell
Horizontal, vertical or inclined mounting; centre of gravity; positioning accuracy
Cycle frequency, temperature, dust and water exposure

Estimate required thrust

For horizontal travel, add acceleration force and motion resistance. Upward vertical motion also needs weight support. Use measured or specified resistance for rolling guides rather than a sliding-friction coefficient.

Horizontal: F = ma + Fres / Upward vertical: F = m(g + a) + Fres

Example: horizontal acceleration

Inputs

Moving mass m = 20 kg
Speed 0 → 0.5 m/s in 1 s → a = 0.5 m/s²
Assumed motion resistance Fres = 15 N

Results

Acceleration force ma = 10 N
Required thrust F = 25 N

The 15 N resistance is an illustrative assumption. Also check breakaway, steady travel and deceleration. This upward-motion equation does not assess lowering or stationary holding.

Follow the calculation for the drive type

A screw drive converts thrust to screw-shaft torque; a cylinder converts pressure into push and pull force. Load support by guides is checked separately.

Position with a screw

Lead is travel per revolution. For an assumed 90% efficiency and 5 mm lead, 25 N requires T = 25 × 0.005 / (2π × 0.9) ≈ 0.0221 N·m. This is load torque at the screw shaft; rotating inertia, preload, bearings and seals add torque.

Push or pull with a cylinder

Distinguish inlet pressure at the cylinder, back pressure and losses. The rod reduces effective retract-side area. Sufficient theoretical force alone does not establish speed or stopping performance.

Compare with component specifications

An offset centre of gravity changes guide reactions. The four-block calculator assumes equal vertical stiffness. A multiplier on vertical weight does not replace lateral-force or acceleration-moment analysis.

Screw: axial load, buckling, permissible speed, life, accuracy and lubrication
Guide: directional loads and moments, mounting stiffness and life
Cylinder: speed, lateral load, cushioning and valve/piping flow
Vertical axis: holding and drop prevention during power or pressure loss

Keep a review checklist

This checklist is a personal reminder, not a safety score or an automatic approval. It is not sent or saved.

Mass, travel, time and mounting orientation are definedAcceleration, steady travel, deceleration and holding are distinguishedScrew load torque is distinguished from total motor torqueActual ratings, life and mounting conditions have been checked

Reference information and illustrative calculations. This content does not guarantee suitability or safety of a design. Confirm the actual materials, component specifications and operating conditions.