Gearboxes

In the field of gearbox development, we primarily deal with the design and testing of mechanical gearboxes and gear shifting. We perform driving tests on a testing track where we use our own measuring equipment. Our technicians are therefore able to evaluate shifting comfort as well as the entire gearbox based on the recored measurements.

We are also involved in the serialisation of mechanical transmissions for other VW Group subsidiaries worldwide.

• 6 years of experience
• 99 cars driven in service life tests
• 1,251 gearboxes built into cars
• 177,021 parts in stock
• 3,100 assembled gearboxes
• 6,100,000 km covered in tests

• Logistics
• Analyses
• Production
• CAD
• Simulations
• 3D printing
• Documentation
• Assembly
• Developments

• PST
• Tests
• Winter
• Telemetry
• Ricardo
• Measurements
• Gear shifting
• Optimisation

Design and implementation of solutions according to the requirements of specific countries, markets and legal regulations of the market in question (e.g. venting in flood areas), while also taking into account changes in related components and related technical systems (clutch, ZMS (dual-mass flywheel), external shifting, etc.)

Implementation of comprehensive model and drawing changes on gearbox parts within the scope of serialisation, model care and further development.

Equipment from PRUSA RESEARCH

Printers help us both in the prototype phase and when drafting designs, as well as when creating various jigs and verification parts, for example, for test benches, workshops, etc. An undeniable advantage of 3D printing is its high speed and low cost.

• Construction and disassembly of prototype mechanical gearboxes and transfer cases
• Assembly and disassembly of prototype gearboxes, crankshafts and drive shafts for test vehicles
• Measurement of parts according to the drawing documentation and creation of a report
• Documentation of construction (assembly and disassembly), its progress and result

• Separate measurement of preload and clearances on gearbox shafts
• Monitoring and documentation of gearbox construction including measurement reports
• Documentation of construction (assembly and disassembly), its progress and results
• Measurement of tightening torques on gearbox bolt connections and turning torques on preloaded gearbox shafts with a digital torque wrench.

Bearing preload measurement with equipment from the company Kistler
Use of Kistler equipment for determining bearing preload, a computer-controlled press allowing the recording of the course of pressing forces, electronically controlled pressure equipment for measuring leakage, specific fixtures for the assembly and disassembly of gearboxes, etc.
Complete measuring equipment for measuring shaft and differential bearing preload in MQ281, MQ350, MQ500 and DQ200 gearboxes

In cooperation with Škoda Auto, we prepare tests of all types of gearboxes, including 4×4 drive, comprising:

• Setting up PST drives according to the installation of the tested parts using special tools and fixtures
• Assembly/disassembly and connection/disconnection of measuring technology (torques, speeds, temperatures, pressures, flow rates, vibrations, acoustics)
• Installation of tested parts into a pallet system
• Complete mechanical and electrical preparation of the test bench (set-up and connection of the drive unit-electric motor or internal combustion engine and brake wheel dynamometers, mounting of test parts onto the test bench, connection and set-up of all necessary media)
• Fitting tested parts with sensors and detectors for data collection

MEASURING STATE
We measure defined shifting characteristics and compare their values with the requirements of the EP 70000 standard or the drawing.
At the end of the equipment’s service life, we then evaluate the change from the initial shifting state.

BLOCK TEST
Gear shifting is blocked against movement, and the gear lever is repeatedly loaded. The shift completes 50,000 cycles in the select direction and another 50,000 cycles in the shift direction.

SPRING ASSEMBLY
In this mode, gear shifting is loaded with 400,000 cycles in the select direction and a total of 1,000,000 cycles in the shift direction in various positions (N-R; 1-2-1; 3-4-3; 5-6-5) at different temperatures.

We provide:

• functional and service life tests of manual gearboxes (for front-wheel drive versions MQ100, MQ200KA, MQ200GA, MQ250, MQ281, MQ350, MQ500 and for 4×4 drive MQ350, MQ500)
• functional and service life tests of articulated and drive shafts
• functional and service-life tests of the external gear mechanism (mechanical and automatic)
• functional and service life tests of clutch mechanisms
• service life tests

On VW Group vehicles at 100,000 km or according to specifications

• on the specified EP Circuit
• on the Ehra testing track or according to specifications

We provide technical support for testing on test tracks in Sweden and Finland

• Our test engineers are responsible for:
• a test report before and after a test
• installing the tested part into the car
• stress spectrum collection of mechanical gearboxes
• measuring shifting comfort
• recording all gears of the gearbox
• measuring the elasticity of the gear lever
• measuring clearances in the shifting system
• acoustic spectrum collection of manual gearboxes and 4×4 drives
• measuring clutch characteristics and clutch clearance
• measuring clutch pedal force

They have knowledge of: Dewesoft Almemo, Catman, Krut, CAN Analyser CANoe, software for G.i.N data loggers.

• acoustics measurement
• shift comfort measurement
• clutch characteristic measurement
• unit drive torque measurement
• data and temperature collection throughout the test (engine, gear shift, gearbox)
• clutch characteristics and clutch pedal force
• testing of articulated and drive shafts
• hot measurement (gearbox operating temperature up to 150°C), and
• cold measurement (after reducing the car temperature to as low as -30°C using a climate box)

The measured data is used to calculate the service life of the drive and to simulate PST tests.

• Load spectrum collection of mechanical gearboxes and 4×4 drives from VW Group vehicles
• Nominal transmission force per wheel min. 5000 Nm
• Recording in all weather conditions – rain, snow, dust, frost, etc.
• Recording on various surfaces – asphalt, gravel, uneven surfaces, ice, etc.
• Recording under different vehicle loads – loaded to the maximum vehicle weight, with a trailer, uphill, etc.

We use equipment from the company Dewetron:

• CT2-Wheel-SET telemetry
• IMC-Wheel-SET telemetry
• DEWESOFT control panel
• MATLAB software

Detection of force depending on the path measured on the shift lever

• Hot measurement (at gearbox operating temperatures of up to 150°C), cold measurement (after reducing the car temperature to as low as -30°C using a climate box and dynamic surface at the Břehyně test track for safety reasons) according to VW methods
• Static and dynamic recording of all gearbox gears
• Measuring the elasticity of the gear lever
• Measuring clearances in the shifting system
• Evaluation of all measured values and processing and comparison of all measured values in a comfort measurement graph

Acoustic spectrum collection of manual gearboxes and 4×4 drives

• Acoustic measurement in various driving modes according to VW methods or EPG specifications
• Measurement of component acoustics before, during and at the end of the test according to specifications
• Evaluation of acoustic spectra and comparison of data between different cars and gearboxes

The results are used as feedback for designers on the effect of modifications on acoustics

During the analysis, various factors such as wear, damage, defective parts, incorrect assembly or unsuitable material are monitored. Visual inspections, measurement and testing are used to identify the causes of a gearbox breakdown.

The results of the analysis provide important input for adjustments and improvements in gearbox reliability. Based on this information, measures such as material changes, design optimisation, seal modifications or appropriate maintenance can be proposed.

In a laboratory analysis of mechanical gearbox components after a test drive, a detailed evaluation of the condition of individual components is carried out.

Visual wear inspection, synchro height measurement, axial/radial clearance measurement