BranchenProdukte Production Kompetenzen

Development and construction of test benches for MT

Measurement test bench for shift actuation

Description

The measurement test bench for shift actuation of manual transmissions is used to determine the position clearance, the internal friction, the degree of efficiency and to calculate the position clearance by limit load, for both directions – shift gate and gear selection.
The positioning system consists of a high-precision linear axis with a spindle drive with shaft joint and a servo motor, a shear-force decoupled force sensor, an inductive position sensor and a fork as an interface to the gear lever. The hand lever is mounted with a twistable top part equipped with two low-friction ball bearing mounted plastic wheels. The later are spanned by the positioning system in such a way that in the contact points the friction and lateral forces are avoided.
After the set-up the test bench determines all the above stated data and displays them in form of a diagram.
 
Application
  • Determination of the position clearance
  • Determination of the internal friction
  • Calculation of the efficiency grade
  • Path measurement by limit load
  • Determination of a cable friction

Measurement technology

  • Linear positioning system
  • Force sensor 100 N / 1000 N
  • Inductive travel sensors
  • Thermocouples Type K

 

 


 

Functional Testing Gear Switch

Description

The task of the function test bench is to measure the gearbox shifter precisely.
In general it takes place before and after endurance testing and when shifters stand out of the field and are available for evaluation.
For this purpose this functional test bench possesses a 3-axial-positioning stage and a load sensor. During testing the load and the position (measuring accuracy load ±1N, Position ±10µm) are defined and it is recorded, when the shifter is closing and opening. The transfer resistance of the shifter is measured in the same way with the help of milliohm meters.
The software possesses a statistics tool for the serial examination. It is possibile to put different measurements of the same shifter types on top of each other.
Besides the mechanical shifter there can be measured the neutral gear sensors (non-contact shifter, pwm or analogue). The test bench software LabVIEW from National Instruments is applied there. 
 

Application

  • Measurement of the transmission shifters with 3-axial- positioning stage
  • Calculation of the transfer resistance and the shift point depending on load and position
  • As an option neutral gear Sensors as well (non-contact shifter, PWM or analogue)
 
Measuring technology
  • Load measuring with strain gauge measuring technology (100N)
  • Measuring of the transfer resistance with a micro-ohm meter
  • Control software LabVIEW
  • Statistics tool for serial examinations 

 

 


 

Continuous operation tests of the external gear switch of manual transmission

Description

The test bench serves for continuous operation tests of the external gear switch in the vehicle installation position taking into account different transmission types and level of motorisation. The tests take place under the air-conditioned terms and can be hold by temperatures from -40°C to 130°C and the relative humidity from 10% to 95%. The gearbox area and the tunnel area can be loaded by different temperatures. Motor reactions on the load change are realised with a floater. The gearshift lever is actuated pneumatically and transmits the shift power over the shift cable to the shift tower, which is loaded through a special spring set.  
During the measurements the position and the power at the shifting lever and the gearshift lever shaft, the ambient air temperature, the temperature in the gearbox area and the tunnel area and the air humidity in the tunnel area are measured, visualised and retained.
The control and visualising program are made with the help of LabVIEW.
Before and after the endurance test the external gear shift mechanism is measured and the wear, the breakages, the abrasion and the cracks are photographically documented.
 
Specifics
  • Separate climate control of the gearbox and the tunnel (-40°C bis +130°C)
  • Air humidity: 10% to 95% relative humidity
  • Simulation of the switching shock
  • Power generation up to 500 N 1,5 Hz
 
Measuring technology
  • Power measurement with strain gauge sensors
  • Non-contact position measuring (Laser and magnetostrictive sensor) 

 

 


 

Endurance test gear switch

Description

Nowadays the function of gear shift mechanisms is no more only to switch the rear lights on and off, but also to control and affect the parking assistant system, the rear view camera and even the motor ignition.
The endurance test bench gear shift mechanism consists fundamentally of three main components: the switch case with an integrated control and visualising computer, the tempered cabinet (measuring temperature area -40°C to +140°C) and the servo motor with the testing device for recording the 6 gear box shifters (mechanically or inductively).
During the endurance test the test bench measures the currents, the tension and the positions of the gear shift mechanism and after an adjustable amount of cycles – the transfer resistance (with the help of a milliohm meter) of the gear shift mechanism.
The test bench software (LabVIEW from National Instruments) controls the load unit, the tempered cabinet, visualises and documents the measured data.
  
Specifics
  • Measuring temperature area: -40°C to +140°C
  • Drive: stepper motor with intermediate transmission
  • Power generation up to 500 N 1,5 Hz
 
Measuring technology
  • Current measurement inductively
  • Measuring of the transfer resistance with micro-ohm meter
  • Position measuring inductively
  • Software LabVIEW

 


 

Endurance  Endurance test bench of pedal system

Description
The test bench allows the endurance test of the vehicle pedal system, consisting of gas and
Brake pedal for automatic transmission vehicles and in addition to the clutch pedal assembly for manual transmissions. At the same time two specimens can be tested in the air-conditioned endurance. The test sequence is defined by technical specifications of the vehicle manufacturer (OEM). The control and monitoring of the test specimens, the collection of values and cycles, and the temperature ( -40 ° C to +80 ° C ) and relative humidity are performed by the software . The mounting position corresponds to the vehicle-specific mounting position in the hip point and pedal commencement point. The operating position is in the levels "X, Y, and Z" displaceable.
The counterforce for the brake and clutch is represented by original vehicle parts.

Application

  • Endurance test of the vehicle pedal system
  • conditioned endurance (-40 ° C to +80 °C , regulated relative humidity)
  • simultaneous testing of two specimens

Specifics

  • integrated displacement measurement system, force / stroke monitoring , torque-free
  • Measurement accuracy <2%
  • Climate chamber -40 ° C to +80 ° C with regulated relative humidity
  • The system is extensible: pedal switch brake / clutch , DMS, gas modulation , displacement sensor analog / digital.
  • The system is flexible: 2/4 cylinder, force up to 1,000 N and 3,000 N, stroke up to 250 mm


HOME  |  COMPANY  |  NEWS  |  ARCHIVE  |  CAREER  |  SITEMAP  |  CONTACT  |  IMPRINT
© hofer 2007
kkCMS