Balancing machines for electric rotors and hybrid rotors

Whether synchronous motor (PSM - permanently controlled synchronous machine),
 asynchronous motor (squirrel-cage rotor) or hybrid rotor: Hofmann offers tailormade machine concepts to compensate for unbalance for every rotor type

The Hofmann machines for unbalance compensation of electric rotors and hybrid
rotors are consistently modular in design. In this way, they can grow at any time with 
the requirements of the user. You can equip your Hofmann balancing machine with 
intelligent measuring technology, or expand it with handling systems up to a fully 
automatic balancing station.

Because Hofmann develops all components and assemblies in-house, all modules 
such as measurement technology, handling systems, unbalance compensation or full 
automation are perfectly coordinated. High availability, durability and perfect 
balancing results are therefore no coincidence. They are the result of many years of 
experience, extensive expertise in balancing technology and high engineering skills.

Depending on your requirements for precision or cycle times, we build our balancing 
machines for e-rotors as 1-, 2- or multi-station machines. We always pay attention to 
the highest precision. Our EHK machines can, for example, be equipped with a 
ground block including a highly sensitive and vibration-isolated measuring platform, 
which enables uniquely precise balancing results.

Due to the vibration-isolated structure, these machines can be set up free of any 
foundation requirements. Our balancing machines are loaded manually, by means of 
robots or loading gantries, or using a specially developed rotary transfer.

Do you have special tasks, such as spinning rotors?
We have the solution! It is often unavoidable to spin the rotor to its later operating 
speed due to a possible displacement of the imbalance within the laminated core of 
the e-rotor or due to the subsequent setting of the permanent magnets at a higher 
speed. Hofmann has developed tailor-made centrifugal stands for this special task.

We test and document the unbalance behavior of rotors when the speed changes. 
We are also happy to carry out spin tests using the contract balancing process. Please 
don’t hesitate to contact us.

E-Mobility – Spin bench

Vertical Spin bench for E-rotors type ESV25-AR

The balancing of electric rotors also includes accelerating them to their later operating speed in the vehicle. This run-up to operating speed - also known as spinning - often leads to a shift in the mass of the laminated cores within the rotor, which in turn leads to a changed unbalance.

With regard to the relatively low unbalance tolerances of the E-rotors, a centrifugal process is essential, so that this is part of the balancing of the rotors.

The Hofmann spin benches are available in a horizontal and vertical orientation.

With the addition of the active balancing system AB9000 developed by Hofmann, it is even possible to spin the e-rotor before the actual balancing process, which in turn means that a complete work step, namely the pre-balancing of the rotors, is eliminated.

 

Loading can be done manually or automatically by a robot.

Special Features

  • Compact design
  • Spin speed up to 20.000 rpm (with a maximum component weight of 25 kg)
  • Internal pre-storage device for robot or manual loading
  • Main spindle direct drive with high-precision collet holder
  • Upper clamping point designed with roller clamping head
  • Automatically operated loading door with safety lock and burst protection, designed for the above-mentioned spin speed and the maximum component weight
  • Optionally with integrated active balancing system (AB9000)
  • Easy accessibility for load/unload
  • Central access to media supply
  • Basic equipment with a Siemens PLC
  • Possibility to connect to CAQ / host computer
    Remote maintenance access

Applications

  • Series production of e-anchors from car e-drives

 

 

E-Mobility - E-Anchor

2-plane measuring and balancing machine for high-speed E-Armature type EHK12.1

For the balancing of e-armatures and hybrid rotors in the context of e-mobility, HOFMANN has developed flexible machine concepts according to the tasks. The low unbalance tolerance, due to the high operating speeds in relation to the rotor weight, places high demands on the measuring platform / device.

Different machine concepts are available depending on the requirements. From the manual 1-station machine (measuring and balancing in one station) to the fully automatic 2-station machine (measuring and balancing separately in 2 stations).

The unbalance compensation can be carried out, depending on the rotor type, by means of axial or radial drilling, or e.g. done by riveting weights. The decision about the required number and structure of the stations depends on the cycle time requirement and the selected machine concept.

Loading can be done manually or automatically via a robot or a loading portal.

Special Features

  • Compact design
  • Quick-opening service door with safety strip
  • Unbalance measurement in 2-plane
  • Pedestals made of stainless steel for measuring the unbalance of magnetic components
  • Mass balancing through manual riveting of weights
  • Modular construction kit designed for maximum flexibility
  • Highest degree of conversion friendliness
  • Ideal accessibility (loading / unloading)
  • Central access to media supply
  • Basic equipment with a Siemens PLC and Siemens HMI.
 Other component systems optionally available.
  • Possibility to connect to CAQ / host computer

Applications

  • Series production of e-armatures and hybrid rotors from car hybrid drives

 

 

E-mobility - E-anchor

2-plane measuring and balancing machine for high-speed E-armature type EHK12-BBH2

For the balancing of e-anchors in the context of e-mobility, HOFMANN has developed flexible machine concepts according to the tasks. The low unbalance tolerance, due to the high operating speeds in relation to the rotor weight, places high demands on the measuring platform.

Different machine concepts are available depending on the requirements. From the manual 1-station machine (measuring and balancing in one station) to the fully automatic 2-station machine (measuring and balancing separately in 2 stations). The unbalance compensation can take place via axial or radial drilling, depending on the rotor type. The decision about the required number and structure of the stations depends on the cycle time requirement and the selected machine concept.

Loading can be done manually or automatically via a robot or a loading portal.

Special Features

  • Compact design
  • Unbalance measurement in 2-plane
  • Decoupled measuring station
  • Highly sensitive measuring platform
  • 3-axis drilling units
  • MQL system for safe & clean drilling e.g. in aluminum
  • Mass balancing via axial or radial drilling
  • Modular construction kit designed for maximum flexibility
  • Highest degree of conversion friendliness
  • Ideal accessibility (loading / unloading)
  • Central access to media supply
  • Basic equipment with a Siemens PLC and Siemens HMI.
Other component systems optionally available.
  • Possibility to connect to CAQ / host computer
  • Remote maintenance access

Applications

  • Series production of e-anchors from car e-drives

 

 

E-mobility - hybrid rotors

1-plane measuring and balancing machine for hybrid rotors type EVW11-BM1

Various machine concepts are available for machining hybrid rotors. From the fully automatic 1-station machine on which the unbalance is measured and also corrected in the same station, to the fully automatic 4-station machine. The decision about the required number of stations depends on the cycle time requirement and the selected machine concept.

The unbalance compensation is usually carried out via axial drilling, but can also be carried out via circular milling on the outer diameter of the workpiece. The loading can be done manually, automatically via a robot or loading portal, or in a linked line via an integrated round transfer.

Special Features

  • Compact design
  • Unbalance measurement in 1-plane
  • Mass compensation via axial drilling, alternative compensation variants (e.g. via milling)
  • Optionally with 90 ° angle drill head for radial unbalance compensation
  • V-Line modular system designed for maximum flexibility
  • Automatic calibration facility with additional TQC software and SQL database
  • Highest degree of conversion friendliness
  • Connection possibility of direct component labeling
  • Optional with DMC recognition
  • Ideal accessibility (loading / unloading)
  • Central access to media supply
  • Basic equipment with a Siemens PLC. 
Other component systems optionally available.
  • Possibility to connect to CAQ / host computer
  • Remote maintenance access

Applications

  • Series production of hybrid rotors from car electric drives

 

 

E-mobility - gear components of the e-axle

2-plane measuring and balancing machine for gear components of the e-axis type EVK11 / II-BM1

A machine with the highest balancing accuracy was designed for machining gears of the electric axis.

The unbalance compensation is done either by axial or radial drilling. Radial drilling is carried out using a 90° angle drill head, which is inserted into the spindle nose of the drilling spindle via the HSK interface.

The loading can be done manually, automatically via a robot or in a linked line via an integrated round transfer.

Special Features

  • Compact design
  • Unbalance measurement in 1 or 2-plane
  • Mass compensation via axial drilling, alternative compensation variants (e.g. via milling)
  • Optionally with 90 ° angle drill head for radial unbalance compensation
  • V-Line modular system designed for maximum flexibility
  • Highest degree of conversion friendliness
  • Connection possibility of direct component labeling
  • Optional with DMC recognition
  • Ideal accessibility (loading / unloading)
  • Central access to media supply
  • Basic equipment with a Siemens PLC. 
Other component systems optionally available.
  • Possibility to connect to CAQ / host computer
  • Remote maintenance access

Applications

  • Series production of gearwheel components for the electric axle from car electric drives