The latest version of MSR TwinDrive simplifies the mechanical transmission system on large vertical lathes. As a result, the design of turning tables is easier.
The MSR drive is composed of two identical gearboxes (TwinDrive system), sharing the driving torque (50%-50%) during turning operations. With the help of the CNC system, which manages the motor preload torque, the system is able to cancel 100% of backlash while maintaining high accuracy. Thus, it allows the execution of additional functions on the C axis, without any additional mechanical devices. For instance, top accuracy is kept during milling operations with one motor driving and the other motor braking.
Before MSR, turning table manufacturers used two different types of drives when a C axis was needed: a main drive for turning operations driven by a big spindle motor and a feed-preloaded gearbox to cancel the backlash during C axis mode that needed to be clutched and unclutched to the crown. In addition, the main drive needed to be shifted to neutral ratio.
The MSR drive eliminates the need for developing a complex and expensive gearbox for the C axis, including a complicated system of clutching/unclutching. A system with two motors is less expensive and easy to manage. In comparison to high duty turning tables used in conventional configurations that require a 160 kW motor, the MSR uses two 80 kW motors, which are more standard and less expensive (despite the fact that there are two of them).
When the diameter of the chuck or part to machine is large, conventional home-made kinematics consisted of using a different stage ratio of 1/1, which resulted in high costs and loss of efficiency. MSR kinematics allow the drive to be placed under the chuck directly meshing with the crown.
For this MSR drive, the latest generation of MSD two-speed gearbox is combined with the cubic R Series right angle bevel gearbox. Supplied as a self-contained sub-assembly, this integrated and compact system is ready to be implemented. Depending on machine arrangement, OEMs can use the bevel box as an option.
The range improves features of the four sizes—MSR330, MSR640, MSR650, MSR660—with torque capacity at pinion from 2000/4000 Nm (2 x 40 Kw motors) up to 9000/18000 Nm (2 x 100 Kw motors) with 3 possible ratio combinations of 7.66&2, 9.88&2, 11.49&3. This approach, combined with pinion/ring ratio of about 10 to 15 offers turn table torques from 20 0000 Nm up to 270 000 Nm and global ratios (gearbox + ring gear) of 77/20 and 172/45
ANDANTEX USA Inc.
Filed Under: TECHNOLOGIES + PRODUCTS, Design World articles, Mechanical, Motors (gearmotors)