1. Overview

In mechanical design, a structural support module is a function module that physically supports each functional module inside a machine, receives loads, and maintains the overall shape and reference structure of the equipment.

If the drive module generates the power required for motion, the power transmission module transfers that power, and the motion / positioning module creates the movement path and position, the structural support module provides the physical foundation that allows all of these modules to be installed and operated stably.

In other words, the structural support module is the design area that becomes the skeleton, reference, load path, and stiffness foundation of the machine.

For example, frames, base plates, columns, brackets, support plates, housings, mounting plates, reinforcing ribs, bearing supports, motor mounts, and linear guide mounting surfaces may all be included in the structural support module.

A structural support module is not simply a plate or frame that fixes components in place.
It directly affects machine stiffness, alignment, vibration, deformation, positioning accuracy, work quality, safety, and maintainability.

Therefore, the structural support module should not be understood as an auxiliary structure that only creates the equipment appearance. It should be understood as a core design module that determines the performance and stability of the entire mechanical system.

2. Definition

A structural support module is a function module that supports each functional component and module in a mechanical system, transfers loads, provides reference surfaces and mounting structures, and stably maintains the overall shape and positional relationship of the machine.

The core purpose of a structural support module can be summarized as follows:

To stably support functional modules inside the machine in accurate positions and manage loads and deformation generated during operation within allowable limits.

The structural support module performs the following functions.

The structural support module can be understood as the physical platform of the entire machine.

3. Role in Mechanical Systems

A structural support module performs the following roles within a mechanical system.

3.1 It Creates the Reference Structure of the Entire Machine

A machine is an assembly of many components, but all components must be assembled around defined references.

The structural support module creates the following references:

• Base reference surface

• Frame reference line

• Guide mounting surface

• Motor mounting surface

• Bearing housing reference

• Tool mounting reference

• Sensor mounting reference

• Height reference

• Centerline reference

• Assembly reference surface

If the reference structure is unclear, assembly accuracy, positional repeatability, and maintainability all decrease.

For example, if the surface where a linear guide is mounted is not flat, or if the reference surfaces of two rails do not match, the slider may jam or positioning error may occur.
If a bearing housing is not installed according to an accurate reference, shaft alignment becomes incorrect, and vibration and wear increase.

Therefore, the structural support module is not a simple frame. It is the structure that creates the reference for machine alignment.

3.2 It Supports and Transfers Loads

During machine operation, loads occur in many directions.

Typical loads include:

• Equipment self-weight

• Product load

• Tool load

• Cutting load

• Pressing load

• Forming load

• Transfer load

• Rotational inertia load

• Vibration load

• Impact load

• Moment load

• Eccentric load

The structural support module must receive these loads and distribute them through an appropriate path to the base or entire frame.

If the load path is unclear, or if loads are concentrated in a specific area, the following problems may occur:

• Frame deformation

• Base bending

• Mounting surface deflection

• Shaft misalignment

• Reduced guide parallelism

• Tool position change

• Increased vibration

• Bolt loosening

• Fatigue failure

Good structural design does not simply “withstand” load. It clearly defines how the load flows through the structure.

3.3 It Manages Stiffness and Deformation

One of the most important factors in a structural support module is stiffness.

Stiffness means how little a structure deforms when load is applied.
If the machine structure deforms under load, the relative position between the tool and the target object changes, and work quality becomes unstable.

Deformation to review includes:

• Bending deformation

• Torsional deformation

• Compressive deformation

• Shear deformation

• Local deformation

• Thermal deformation

• Deformation caused by assembly stress

• Dynamic deformation

For example, if the frame of cutting equipment bends, the cutting position changes.
If the base of pressing equipment bends, the pressure distribution becomes uneven.
If the structure of sealing equipment twists, the parallelism of the sealing jaws is lost, and leakage may occur.

Therefore, the structural support module must secure stiffness that matches the required work quality.

3.4 It Reduces Vibration and Noise

Machine structure strongly affects the generation and transmission of vibration.

Vibration may be caused by:

• Motor rotation

• Eccentric rotating bodies

• Cutting impact

• Reciprocating motion

• Chain or belt drives

• Pneumatic cylinder impact

• High-speed transfer

• Unbalanced loads

• Resonance

• Insufficient frame stiffness

To reduce vibration, the structural support module must have sufficient stiffness, appropriate mass, reinforcing structures, vibration isolation, fixing methods, and support conditions.

Large vibration can cause the following problems:

• Positioning error

• Reduced product quality

• Increased noise

• Bolt loosening

• Sensor misdetection

• Reduced bearing life

• Fatigue failure

• Increased operator fatigue

Therefore, the structural support module must consider not only static load but also dynamic load and vibration characteristics.

3.5 It Maintains the Positional Relationship Between Modules

Each functional module in a machine must have an accurate positional relationship with the others.

Examples include the following.

The structural support module is the foundation that maintains these positional relationships.

If the structure is weak or the reference surfaces are unclear, each individual module may function correctly, but the entire machine may become unstable.

3.6 It Secures Safety and Equipment Stability

The structural support module is directly connected to equipment safety.

Safety-related factors to review include:

• Prevention of equipment overturning

• Prevention of frame failure

• Safety factor for load support

• Support of vertical loads

• Prevention of movement caused by vibration

• Support of high-speed rotating bodies

• Mounting of covers and protective structures

• Operator load or access load

• Fixing of movable equipment

• Earthquake or impact conditions

If the structural support module is insufficient, it can lead not only to equipment failure but also to operator safety problems.

4. Main Types of Structural Support Modules

Structural support modules can be divided into several types according to their role in the machine structure.

5. Types of Structural Support Methods

5.1 Base Plate Structure

A base plate structure supports the entire machine or major modules from the lowest part of the equipment.

Typical components include:

• Steel plate base

• Aluminum plate

• Cast base

• Surface-plate-type base

• Machined base plate

• Anchor holes

• Leveling feet

• Reinforcing ribs

Advantages

• Reference surfaces are easy to create.

• The load of the entire equipment can be supported stably.

• It is advantageous for module mounting and alignment.

• Stiffness is relatively easy to secure.

• It is suitable for precision equipment.

Points to Consider

• Plate thickness and flatness are important.

• Machining cost can be high.

• Large bases require review of thermal deformation and deformation during transport.

• Reinforcement is required at concentrated load areas.

• Drainability must be considered to prevent water and residue accumulation.

Design Review Points

• Base thickness

• Flatness

• Machined mounting surface range

• Load position

• Anchor position

• Leveling structure

• Rib reinforcement

• Thermal deformation

• Drainability

• Maintenance accessibility

5.2 Frame Structure

A frame structure creates the overall exterior shape and spatial structure of the equipment.

Typical components include:

• Square pipe frame

• Welded frame

• Aluminum profile frame

• Stainless steel frame

• Modular assembled frame

• Cross member

• Reinforcing brace

Advantages

• Large equipment structures are easy to create.

• Internal space can be secured.

• Panels, covers, and modules can be mounted easily.

• Welded or assembled construction can be selected.

• It is suitable for forming the overall equipment appearance.

Points to Consider

• Welding deformation may occur.

• In assembled frames, joint stiffness must be reviewed.

• Torsional stiffness may be insufficient.

• Precision reference surfaces may require separate machining.

• The structure may become vulnerable to vibration.

Design Review Points

• Frame section

• Welding method

• Fastening method

• Torsional stiffness

• Cross member layout

• Module mounting position

• Assembly reference

• Transport and installation

• Cover mountability

• Cleanability and drainability

5.3 Column and Post Structure

Column and post structures support vertical loads and vertical position references.

Typical components include:

• Vertical column

• Guide post

• Support post

• Gantry column

• Press column

• Height adjustment post

• Fixed bracket

Advantages

• Suitable for supporting vertical loads.

• Easy to combine with lifting structures.

• Suitable for creating tool approach direction.

• Can provide height reference.

• Suitable for pressing, sealing, and assembly equipment.

Points to Consider

• Tilting caused by eccentric load must be reviewed.

• Stiffness of the column mounting surface is important.

• In tall structures, vibration and deflection may increase.

• Verticality and parallelism are important.

• Operator access and safety covers must be considered.

Design Review Points

• Column section

• Height

• Verticality

• Eccentric load

• Fixing method

• Connection stiffness with the base

• Reinforcing ribs

• Vibration

• Working space

• Maintenance accessibility

5.4 Bracket and Mounting Plate Structure

Brackets and mounting plates mount motors, sensors, cylinders, guides, covers, piping, and similar components at specific positions.

Typical components include:

• Motor bracket

• Sensor bracket

• Cylinder bracket

• Guide bracket

• Cover bracket

• Mounting plate

• Adapter plate

• Adjustment slot

Advantages

• Component positions can be set easily.

• Adjustment structures are easy to create.

• Suitable for modular design.

• Maintenance and replacement are easy.

• Various components can be mounted flexibly.

Points to Consider

• If bracket stiffness is insufficient, position becomes unstable.

• Long cantilever structures can increase vibration.

• Adjustment slots are convenient, but fastening stiffness may decrease.

• Sensor brackets can be vulnerable to impact and vibration.

• In food machinery, gaps and horizontal surfaces should be reduced.

Design Review Points

• Bracket thickness

• Bending stiffness

• Fastening position

• Adjustment range

• Slot direction

• Mounting reference

• Vibration influence

• Interference

• Removability

• Cleanability

5.5 Housing Structure

A housing structure supports and protects bearings, gears, shafts, drive components, and internal mechanisms.

Typical components include:

• Bearing housing

• Gear housing

• Motor housing

• Spindle housing

• Cover housing

• Sealing housing

• Case structure

Advantages

• Internal components can be protected.

• Bearings and shafts can be supported accurately.

• Lubrication structures can be included.

• Noise and contamination can be reduced.

• Suitable for modular assembly.

Points to Consider

• Machining accuracy is important.

• Thermal expansion must be considered.

• Lubrication and sealing structures may be required.

• Internal maintenance accessibility must be considered.

• In food machinery, contaminant discharge and cleanability must be reviewed.

Design Review Points

• Bearing position

• Shaft alignment

• Housing stiffness

• Machining reference

• Seal structure

• Lubrication method

• Thermal expansion

• Disassembly

• Drainability

• Contamination prevention

5.6 Rib and Reinforcement Structure

Ribs and reinforcement structures are used to increase the stiffness of frames, plates, brackets, and columns.

Typical components include:

• Reinforcing rib

• Gusset plate

• Triangular reinforcement plate

• Cross brace

• Box structure

• Bent sheet structure

• Double plate structure

Advantages

• Stiffness can be increased while limiting weight increase.

• Bending and torsion can be reduced.

• Vibration can be lowered.

• Concentrated load areas can be reinforced.

• Deformation of thin plate structures can be reduced.

Points to Consider

• Rib position must match the load direction.

• Welded ribs can create deformation.

• Gaps that are difficult to clean may be created.

• Unnecessary ribs can reduce manufacturability and cleanability.

• Stress concentration should be avoided.

Design Review Points

• Load direction

• Rib position

• Rib thickness

• Welding deformation

• Stress concentration

• Bending stiffness

• Torsional stiffness

• Cleanability

• Manufacturability

• Weight increase

6. Main Design Criteria

The following criteria should be reviewed when designing a structural support module.

6.1 Load Conditions

The first factor to review is the load that the structure must receive.

If load conditions are not understood correctly, structural deformation, vibration, fatigue failure, and positioning error may occur.

6.2 Stiffness and Deformation

The structural support module must remain within allowable deformation when loads are applied.

Review points include:

• Bending stiffness

• Torsional stiffness

• Compressive stiffness

• Shear stiffness

• Local deformation

• Base deflection

• Bracket bending

• Column tilting

• Mounting surface deformation

• Working position change

A structure with insufficient stiffness may operate at first, but it causes unstable quality and reduced component life during long-term operation.

6.3 Reference Surfaces and Alignment

The structural support module must provide references for assembly and alignment.

Review points include:

• Reference surface position

• Reference surface flatness

• Parallelism of rail mounting surfaces

• Perpendicularity of motor mounting surfaces

• Concentricity of bearing housings

• Tool mounting surface position

• Sensor reference position

• Adjustment reference

• Position reproducibility after reassembly

• Product changeover reference

If alignment references are unclear, assembly time increases, and product quality may change after maintenance.

6.4 Vibration and Resonance

The structural support module must consider vibration and resonance.

Review points include:

• Motor rotational vibration

• Eccentric rotating body

• Reciprocating motion frequency

• Cutting impact cycle

• Natural frequency of the frame

• Bracket vibration

• Guide support stiffness

• Base fixing condition

• Need for vibration isolation pads

• Noise transmission path

When resonance occurs, even small excitation forces can be amplified into large vibration.
Therefore, structural vibration review is necessary for high-speed equipment, repeated impact equipment, and precision positioning equipment.

6.5 Material and Manufacturing Method

The performance of a structural support module varies depending on material and manufacturing method.

Material selection should not be based only on strength.
Precision, vibration, corrosion, cleanability, manufacturability, cost, and maintainability must be considered together.

6.6 Fastening and Assemblability

Structural support modules are usually assembled by bolting, welding, pin fixing, or anchor fixing.

Review points include:

• Bolt strength

• Fastening position

• Fastening accessibility

• Possibility of repeated disassembly

• Need for locating pins

• Welding deformation

• Assembly sequence

• Adjustment margin

• Prevention of fastening loosening

• Protection of reference surfaces

Fastening sections are not simple connection points. They are part of the load transfer path.
Fastening stiffness and assembly repeatability must be reviewed carefully.

6.7 Maintainability and Accessibility

The structural support module determines maintenance accessibility for other modules.

Review points include:

• Motor replacement space

• Bearing replacement space

• Guide lubrication accessibility

• Sensor adjustment accessibility

• Cover removability

• Tool replacement space

• Cleaning accessibility

• Internal access path

• Crane or lifting space

• Spare part replaceability

If the structure is too closed, inspection and replacement become difficult.
If it is too open, safety and stiffness may decrease.

6.8 Cleanability and Hygiene

In food machinery, cleanability and hygiene of the structural support module are very important.

Review points include:

• Minimization of horizontal surfaces

• Prevention of water accumulation

• Closing of open sections

• Drainage direction

• Minimization of exposed bolts

• Removal of gaps and pockets

• Weld finishing

• Surface roughness

• Corrosion prevention

• Separation between food-contact and non-food-contact areas

If water and raw material residue accumulate on frames or brackets, bacterial growth, corrosion, odor, and foreign matter contamination may occur.

7. Interface with Other Modules

The structural support module is connected to all function modules.

7.1 Relationship with the Drive Module

The structural support module mounts and supports motors, cylinders, and actuators.

Review points include:

• Is the motor mounting surface sufficiently stiff?

• Is cylinder reaction force transferred stably to the frame?

• Is drive vibration not excessively transmitted to the structure?

• Are alignment references clear?

• Is there space to replace the drive section?

• Can the drive section be protected in a washdown environment?

7.2 Relationship with the Power Transmission Module

The power transmission module includes shafts, bearings, gears, belts, and chains, so it strongly depends on the alignment and stiffness of the structural support module.

Review points include:

• Is the shaft support span appropriate?

• Are bearing housing reference surfaces accurate?

• Can pulleys and sprockets be aligned?

• Is the reducer mounting surface sufficiently stiff?

• Is there no frame deformation caused by belt tension?

• Does chain load not overload the structure?

7.3 Relationship with the Motion / Positioning Module

The motion / positioning module strongly depends on the quality of guides and reference surfaces.

Review points include:

• Is the linear guide mounting surface flat?

• Can parallelism between rails be secured?

• Does slider load not deform the frame?

• Is the stopper mounting section sufficiently stiff?

• Is the home sensor reference stable?

• Does the position remain unchanged after long-term operation?

7.4 Relationship with the Processing / Working Module

The processing / working module generates working loads, and the structural support module must receive those loads.

7.5 Relationship with the Tooling Module

Because the tooling module directly determines product quality, it is sensitive to deformation of the structural support module.

Review points include:

• Is the tool mounting surface sufficiently stiff?

• Does tool load not change the position?

• Is the reference reproduced after tool replacement?

• Are tooling accessibility and replaceability secured?

• Is tool vibration not amplified by the structure?

7.6 Relationship with the Control / Sensing Module

Sensors are mounted on the structure, so they are affected by the stability of the structural support module.

Review points include:

• Does the sensor bracket not shake?

• Does the sensor reference position not change?

• Does vibration not cause misdetection?

• Does the wiring path not interfere with the structure?

• Is sensor replacement and adjustment easy?

• Is the sensor protected from cleaning water and impact?

7.7 Relationship with the Safety / Protection Module

Safety covers, interlocks, and protection panels are mounted on the structural support module.

Review points include:

• Is the cover frame sufficiently stiff?

• Is cover removal easy?

• Is the interlock switch position stable?

• Does the protective panel not vibrate?

• Can it withstand operator access load?

• Is the emergency stop button mounted in an appropriate position?

8. Application in Food Machinery

In food machinery, the structural support module must be reviewed especially carefully in terms of hygiene, cleanability, corrosion prevention, and drainability.

Important design conditions for structural support modules in food machinery include the following.

In food machinery, a frame being strong is not enough.
Water and raw materials must not accumulate, operators must be able to clean the structure easily, and corrosion or foreign matter generation must be minimized.

Therefore, the structural support module is also a core module from the perspective of hygienic design.

9. Common Design Mistakes

Common design mistakes in structural support modules include the following.

9.1 Considering Strength but Not Stiffness

A structure is not good just because it does not break.
Even if it does not fail, excessive deformation reduces positioning accuracy and work quality.

In machine structures, stiffness is often more important than strength.

9.2 Ignoring the Load Path

If it is unclear where the load is generated and where it is transferred, stress becomes concentrated in specific areas.

A structure with an unclear load path can cause frame deformation, bolt loosening, bearing damage, and poor guide alignment.

9.3 Considering Reference Surfaces Too Late

If reference surfaces are determined after structural design, assembly and alignment become difficult.

The mounting positions of linear guides, bearings, motors, tools, and sensors should be determined together with reference surfaces from the early design stage.

9.4 Designing Weak Brackets

Sensor, motor, and cylinder brackets may look small, but they strongly affect positional stability.

Long brackets, thin plate brackets, and brackets with many slots can especially cause vibration and position change.

9.5 Reviewing Cleanability and Drainability Too Late

In food machinery, the structural support module is directly connected to cleanability.

If the frame is designed first and cleanability is reviewed later, water accumulation, gaps, pockets, exposed bolts, and cleaning blind spots easily occur.

10. Design Checklist

The following questions can be used when designing a structural support module.

10.1 Load Review

• What static and dynamic loads must the structure receive?

• What is the maximum load generated during work?

• Are there impact loads or eccentric loads?

• Through what path is the load transferred to the base?

• Is the safety factor appropriate?

10.2 Stiffness and Deformation Review

• Is deformation within allowable limits under load?

• Are bending and torsion of the frame, base, and brackets acceptable?

• Does the tool position not change under load?

• Does the guide mounting surface not deform?

• Is position maintained after long-term operation?

10.3 Reference Surface and Alignment Review

• Are assembly reference surfaces clear?

• Are there machined references for linear guide and bearing mounting surfaces?

• Can motor and shaft alignment be secured?

• Is position reproduced after tool replacement?

• Is the sensor reference position stable?

10.4 Vibration Review

• Does vibration occur in rotating, reciprocating, or cutting sections?

• Does the frame natural frequency not overlap with operating frequency?

• Do brackets or covers not shake?

• Is vibration isolation required?

• Does vibration not affect sensors and product quality?

10.5 Manufacturability and Assemblability Review

• Has welding deformation been considered?

• Are machined reference surfaces secured?

• Is the assembly sequence feasible?

• Is fastening accessibility good?

• Is transport and installation possible?

• Are leveling and anchor fixing possible?

10.6 Maintenance and Cleaning Review

• Can major components be accessed?

• Can motors, bearings, sensors, and guides be replaced?

• Does cleaning water not accumulate?

• Are gaps and pockets minimized?

• In food machinery, can corrosion and foreign matter generation be prevented?

• Are covers and panels easy to remove?

11. Summary

A structural support module is a core function module that supports each function module in a mechanical system, transfers loads, provides reference surfaces and mounting structures, and maintains the overall shape and positional relationships of the machine.

This module may consist of base plates, frames, columns, brackets, mounting plates, housings, reinforcing ribs, rail support structures, cover support structures, and leveling structures.

A structural support module is not simply a structure that fixes components.
It is a design area that determines machine stiffness, alignment, vibration, deformation, positioning accuracy, work quality, safety, maintainability, and cleanability.

When designing this module, load conditions, load paths, stiffness, deformation, reference surfaces, alignment, vibration, materials, manufacturing methods, fastening, assemblability, maintainability, and cleanability must be reviewed together.

The structural support module is also directly connected to the drive module, power transmission module, motion / positioning module, processing / working module, tooling module, control / sensing module, and safety / protection module.

In food machinery, the structural support module is closely connected to hygienic design.
Prevention of water accumulation, drainability, cleaning accessibility, corrosion prevention, separation of lubricated areas, and prevention of foreign matter contamination must be considered carefully.

Therefore, the structural support module should be understood not as a simple frame or support structure, but as a core design module that supports machine performance, stability, precision, safety, and hygiene.