Swiss Type Automatic Lathe SB-16R/20R Newly Released
Re-designed and Re-launched SB Series Featuring High Rigidity and Accuracy
Star Micronics has successfully developed SB-16R and SB-20R for a maximum machining diameter of ø16mm and ø20mm each as renewed Swiss type automatic lathes (NOTE 1) in the SB series.
Both models include type C, a 5-spindle control type which is equipped with a sub spindle and type E, a 7-spindle control type which is equipped with a sub spindle and a tool post especially designed for back working, totaling four models to launch onto the market.
Mainly targeting the automobile and information-communication equipment fields, SB-16R/20 type E is scheduled to be released in July, 2013 and type C in August, 2013 in the global market.
Since the release of the initial model SB-16 in 2003, the SB series has been highly esteemed as a best selling series. SB-16R and 20R are re-launched as successor models to this series.
The tool post utilizes a Star original slanted slide guideway (NOTE 2). The enhanced machine rigidity allows continuous machining with stable accuracy. The main spindle is a build-in type and has a C-axis control function as standard equipment. The type E, a higher model, incorporates this C-axis control function as standard equipment in the sub spindle as well.
There are two options available for the gang-type tool post for front working: a four-power tool type and a five-power tool type, according to customer’s needs. As for the five-power tool type, three out of five tools can be changed freely to allow various combinations of tooling layouts.
The tool post especially designed for back working mounted on type E is ready to accommodate a tool rotation drive unit. This enhances functions of complex machining, including eccentric hole drilling, slotting, etc., on the rear end.
The NC unit has a variety of help functions such as an alarm help function to monitor the alarm contents on the NC screen. In addition, a swing-type operation panel, manual pulse generator which is convenient for set-up operation, etc. contributes to the improved operability and workability.
Note 1: Swiss-type automatic lathe
The Swiss-type automatic lathe was devised as watch component processing machinery in Switzerland in 1870s. Known as a “sliding head-type automatic lathe” as well, it has remarkable characteristics of high-precision cutting of components with longer length compared with the diameter.
In general, if long and narrow parts are processed with a general-purpose lathe, flexure will occur on the workpiece, making finishing with the correct dimensions impossible. The Swiss-type automatic lathe utilizes a guide bush to function as a material steady rest. The tool, positioned at a certain distance from the guide bush, gives a cutting motion only the direction of outside diameter. This allows the workpiece to be cut accurately with no flexure. As for axial motion, the headstock, rather than the tailstock, moves while clamping a workpiece.
Note 2: Slanted slide guideway structure
The machine main body base and the tool post are slanted and each sliding surface is in a trapezoidal shape, called a dovetail structure. This structure allows each sliding surface to come into contact with its entire plane to improve the machine rigidity. The ball screw center and the cutting point are close to each other to reduce a load (moment load) applied in the direction of torsion caused by cutting resistance.