Honing Machine, whose stroke speed is 2 times faster than before has been developed, and will appear at the 24th Japan International Machine Tool Fair.[08.10.16] Topics & News Release: Toyo Advanced Technologies Co., Ltd.

Toyo Advanced Technologies Co., Ltd. (head office: Minami-ku, Hiroshima, Japan; President: Yasuto Tatsuta) will be exhibiting its latest space-saving, high-performance machines at the 24th Japan International Machine Tool Fair, to be held at Tokyo Big Sight from Oct. 30 to Nov. 4, 2008. Toyo's theme for this exhibition is "Open the Grinding Future, Open the Honing Future." In addition to the newly developed T-32N-C, high-speed CNC honing cell and T-180C, vertical grinding machine for injection nozzle, some other products will be exhibited, including a new type of high-frequency wheel head, which can be run at a wide range of rpm.

The newly developed T-32N-C is a compact 1.6m wide honing machine which helps shorten production lines. A new design using twin servomotors for vertical driving of the work spindle enables a high stroke speed of 60 m/min, resulting in a stroke speed twice faster than that of previous machines. As a result, the cell has a production capacity as good as or better than a dual-spindle honing machine, even though it only has one spindle. In addition, the cell makes stable, high-precision machining by introducing a highly rigid gate structure and TFCS-II (Toyo Force Control System II).

The exhibited machine has single-spindle specifications, but a variety of additional options are also available, including dual-spindle specifications for further improvement of production, ATC (auto tool changer), APC (auto pallet changer), and transfer equipment. These options deal with a transfer line linking multiple cell machines, or varying-type/varying-quantity production. Toyo will begin taking orders for this machine at the Japan International Machine Tool Fair.

　T-180C is a vertical grinding machine developed for machining small parts, such as fuel injection nozzles, which require high precision grinding on seat faces. In addition to inner and outer diameter faces and end faces, this unit is capable of inclined grinding to suit the angle of the seat face. Even though the machine is equipped with a work transfer robot, the dimensions are as compact as 1,200 mm (width) x 1,660 mm (height), so it saves space and has excellent handling performance.
A rotation precision of 0.1 μm or less is achieved by introducing a newly developed dynamic pressure bearing on the work spindle. This unit realizes high-precision, high-efficiency grinding through innovations including development of a new 180,000rpm high-frequency wheel head with a built-in AE (acoustic emission) sensor and introduction of linear motors and linear scales for X-axis and Z-axis. In the case of seat face grinding, any angle can be set through simultaneous axis control of X and Z, and this dramatically reduces set-up time for high-diversity, low-volume production. For mass production, the machine enables grinding with higher precision and efficiency by inclining X-axis to match the angle of the seat face.
The same model was exhibited at IMTS 2008, held in Chicago in September, 2008, and numerous inquiries have already been received. In Japan, we will begin taking orders at the Japan International Machine Tool Fair.

　In terms of components, we will be exhibiting three types of high-frequency wheel heads which consume less air. In particular, HFD06W-50 (8 kW output) can be used in wide range from 30,000 to 60,000 rpm, thereby enabling production with a single wheel head, even with a machine used for high-diversity, low-volume production.
At the exhibition hall, Toyo display will not only showcase machines and components, but also provide information on our vertical internal grinding machine series, which have increased the model lineup. The exhibit will provide an overview of our product line, ranging from compact T-180C to ultra-large T-186-2T. We also plan to disclose information on T-183C-2S machine with large turret table, which is currently under development.

This model adopts a new twin servomotor drive system, that is, the number of servomotors for vertical drive of the work spindle has been increased from one to two. Furthermore, stroke speed and follow-up performance of the work spindle have been improved through removing weight from the drive unit and other techniques. As a result, work spindle runs two times faster than that of current honing machine, and achieves a high-speed stroke of 60 m/min, which was previously difficult to achieve. Due to this high-speed stroke, the T-32N-C has a production capacity as good as or better than a dual-spindle machine, even though it only has a single spindle.

In addition to a highly rigid gate structure, the cell employs a structure which efficiently disperses and absorbs the vertical energy of the work spindle at the column and the head. The positions of the twin servomotor guides and the work spindle are also balanced, to ensure a layout that can withstand high loads. The sensitivity level of the sensor has also been improved through the arranging of the feed axis and machining strength sensor in series, and the development of a new TFCS-II system has taken our unique feed control to the higher level. Thanks to these innovations, this machine enables high-precision grinding with uniform quality and ‘one rank machining’.

Rotation precision has been kept at 0.1 μm or less by developing a new dynamic pressure bearing for the work spindle. A newly developed high-frequency wheel head with a built-in AE sensor, which detects grinding wheel contact during dressing and grinding are mounted on the machine to ensure stable grinding precision. Positioning with even greater precision than before is achieved by employing fully closed control using linear motors and optical linear scales for the moving axes (X and Z). This results in stable, high-precision machining.

The newly developed wheel head performs at 180,000 rpm and enables high-efficiency grinding. Furthermore cycle time can be made shorter than before by reducing non-machining time with the help of linear motor drive and AE sensor. Two methods for grinding seat faces can be selected to suit the application. For high-diversity, low-volume production, grinding can be done at any angle through high-precision, simultaneous control of X- and Z-axes, thereby simplifying set-up procedures. In mass production, on the other hand, NC traverse machining can be done by inclining X-axis to match the seat face angle, which leads to more grinding precision and accuracy than simultaneous two-axis control.