The machines for balancing and measuring the principal axis or the center of gravity of crankshafts and conrods in serial production are of modular design and are planned according to customer-specific requirements.
Depending on the requirements, they are designed as plain unbalance measuring machines without any correction, or they can be combined with an additional station that automatically corrects unbalance by drilling. The modular crankshaft balancing machines for serial production can be produced as single-station or multi-station machines with or without integrated automatic unbalance correction. The soft-bearing measuring machines do not require an expensive foundation and are not susceptible to external vibration noise. Special software optimally distributes the measured unbalance to the available correction planes and angular positions. For small series or as an audit machine, adapted universal balancing machine concepts are available that can also be equipped with a manual drilling correction system.
Machines for the mass-centering of crankshafts determine the principal axis of the cast or forged blank. Crankshafts that are balanced with reference to their principal axis exhibit a lower initial unbalance. This results in reduced cycle times for the subsequent balancing machine and to a more efficient process overall.
The position of the center of gravity of conrods is determined on conrod taring systems. Material removal by milling with automatic 3D deburring tools ensures that the center of gravity is in the defined range and that an engine with this conrod runs smoothly. Hofmann’s conrod taring systems feature a short cycle time.
Types: KHK21-BL1, KHK21-BL1, KHK12-BL1, KHK21-BH2
These balancing machines are usually loaded with the aid of a loading gantry, have a modular structure and allow an extension that can be adjusted to the production conditions. They are designed to balance crankshafts in multiple correction planes in one or more steps.
Single-station measuring machine with machine cladding and two-part access door. The measuring system comes with servo drives (master/slave), axial and radial alignment system and maintenance-free sensors. The measuring frame is lockable, and the temporary resting position is linearly adjustable. The measuring drive is equipped with supporting V-blocks and tension levers, and weights to compensate asymmetrical parts can be mounted on disks. After the measuring process, the interlinked system enables the transmission of coordinates in X and Y components to the subsequent OP. Operation occurs from a 19“-touchscreen (manual functions of WIN CC and measuring computer operation (Windows®)).
Type UHK 12-ZM1
Single-station balancing machine with machine cladding. The measuring system consists of force-measuring, permanently calibrated bearing pedestals that feature an easy adjustment in T-slots and locking using an open-end wrench. For a new rotor type, only the correction planes and radii are to be entered in the measuring system. The measuring drive is implemented as a belt drive with asynchronous motor which is horizontally adjustable on linear guides. Operation is performed via a 19” touchscreen.
Types: UHK 12, UHK 16, UHK 19
Single-station balancing machine with sliding guard or guard fence. The measuring system consists of a frequency-controlled belt drive, maintenance-free measuring transducers and axially adjustable bearing pedestals with hardened measuring rollers and thrust stops. A lifting device to take up the drilling forces is available. The measuring drive is a belt drive. A drilling spindle arranged in the gantry performs the unbalance correction with a manual or an automated feed slide. The unit is manually supported by a line laser, positioned to the correction planes and clamped pneumatically. Operation occurs from a 19” touchscreen (manual functions of WIN CC and measuring computer operation (Windows®)).
The type PHW measuring and taring machines are put together based on the required cycle time and the scope of performance (deburring, brushing). The full assembly enables the weighing and taring of both connecting rod end bores and deburring with a cycle time of approx. 4.8 seconds.