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Call:1-888-551-3082 International: 1-919-443-0207
Call:1-888-551-3082 International: 1-919-443-0207

Indramat 1MB Motors

Indramat 1MB Motors

Rexroth 1MB motors are frameless, liquid-cooled, asynchronous motors that serve as direct drives in motor spindles, enhancing the rigidity and precision of the spindle system. These motors are positioned between main spindle bearings to maximize the stiffness of the motor spindle, thereby enabling high precision in operations such as turning, milling, and grinding. The design allows for the main spindle and the C axis to be driven by a single motor, which is particularly advantageous in lathe operations. The versatility of the 1MB motors makes them ideal for a wide array of machine tools, including transfer lines, processing centers, and machines crafted for specialized purposes.

Technical Data

The 1MB Motor comes in various frame lengths to suit a wide range of automation needs. Below is an example of technical specifications from a few variations. Please refer to official Indramat documentation for in-depth specs.


Description Symbol Unit 1MB140
Frame length B D F H
Winding code 4A 4B 4A 4B
Rated torque MN Nm 7 14 24 34
Rated speed nN rpm 7500 5000 4000 3000
Rated power PN kW 5.5 3.7 6 7.5 10.5


Description Symbol Unit 1MB240
Frame length B
Winding code 4A
Rated torque MN Nm 62
Rated speed nN rpm 1000
Rated power PN kW 6.5


Description Symbol Unit 1MB375
Frame length B D
Winding code 6B 6D
Rated torque MN Nm 636 875
Rated speed nN rpm 600 300
Rated power PN kW 40 55

Appropriate Use

The 1MB frameless spindle motors from Bosch Rexroth are specialized for integration as direct drives within motor spindles. These motors are designed to operate with specific control and monitoring systems, and might necessitate additional sensors and actuators, depending on the application. A variety of drive controllers, differentiated by drive power and interface types, can be utilized with these motors to meet the demands of different applications. It is important to note that these motors should only be used with the accessories and parts listed in the official documentation; unlisted components should not be connected or mounted. The operation of the 1MB motors is restricted to the configurations and component combinations detailed by the official software and firmware function descriptions. Prior to use, each drive controller must be appropriately programmed to ensure the motors perform the desired functions. Lastly, these motors should only be used under the conditions outlined in the manual, which includes specifications for temperature, protection system, humidity, and EMC requirements. Below is a summary of a few of those specifications.

- Permissible ambient temperature: 0 to 40°C
- Permissible storage and transport temperature: -20 to +80°C
- Insulation class according to DIN VDE 0530-1: F
- Class of motor protection: IP00