Pinnacle Machine Tool Co., Ltd., founded in central Taiwan back in 1976, has released a series of feature-laden five-axis (X, Y, Z, plus B and C axes) CNC machining centers to cater to high-end manufacturers looking for machines that are economical in price yet uncompromising in precision and quality. The company hopes that these new products will help keep it competitive in the ever-more-difficult international environment.
Pinnacle’s BX machines feature a patented turntable docking with T-slot table to form a bigger table for larger workpieces.
This latest family of vertical machining centers is dubbed the BX series: the BX300A, BX500A, and BX700A. The machines are outfitted with a built-in spindle swiveling minus-and-plus 120 degrees and turning at 15,000 rpm, as well as a 360-degree rotary table. The five axes use direct drive motors to eliminate vibration and backlash.
The unique table design of the BX family, which enables the turntable to seamlessly dock with a standard T-slot table on the same plane to form a larger table for bigger workpieces, is patented in Taiwan and China.
Of the three models, the BX700A has the biggest turntable at 630mm in diameter. The corresponding size for the BX500A is 500mm and for the BX300A is 320mm. The table works as B and C axes.
The BX models have an axial of 30 meters and a rotary axis that turns at 50 revolutions per minute. The machines have a guaranteed machining accuracy of at least 20μm on finished products, with each axis promising accuracy within fiveμm.
Rigid bearing and hydraulic systems in the BX models assure a minimum 0.0001 arcsecond of positioning accuracy, with permanent magnetic motors providing high-torque output and power to meet different cutting demands.
The machines have an axial preload bearing three times more rigid than a radius bearing to overcome B-axis cutting vibrations in both the vertical and horizontal planes, with a 360-degree drum brake for an even, firm grip on the B axis shaft to achieve high rigidity for supporting the swing milling head
The B axis swivel milling head is outfitted with a dual-pitch worm gear set made up of alloy steel worm wheels and an aluminum bronze alloy 7 worm shaft, with higher and thicker teeth on the shaft providing low friction and efficient torque transmission.
Deformation and backlash on ball screws along the X, Y, Z axes are significantly reduced by oil coolant running through the hollow screw rods. Roller guideways ensure optimum rigidity and speed of X-, Y-, and Z-axis travel. High response pneumatic cylinders and an air reservoir tank generate a counterbalancing force to ensure fast, stable Z-axis movement, assuring an extremely smooth surface finish on workpieces.
The BX’s built-in spindle swings minus-plus 120 degree to process at a wider angle.
Suitable for Large and Complicated Parts
The BX series is suitable for making relatively large items with multi-asymmetric faces, such as turbine fan blades for aircraft and precision molds for electronic components.
The machines are controlled by the Heidenhain iTNC530 system, a German product which allows contract buyers to monitor the real-time production of products on their computers through an Ethernet wireless connection.
The BX family is designed to simplify the setup and production of complicated, multi-sided parts without losing precision, accuracy, or time.
The BX family follows the AX series of machines, which feature a 110-degree-swing A axis with the same turntable design as BX series. The AX series is ideal for making smaller precision components with multi-asymmetric faces such as those used in aircraft and medical equipment, as well as fan blades for car turbochargers.
The AX series includes the AX320 and AX450 models. The AX450 has a rotary table measuring 450mm in diameter, and the AX320's table measures 320mm. The AX320 table's tilt along the A-axis ranges from -120 to +30 degrees; for the AX450, the tilt is -110 to +110 degrees.
The AX320's X, Y, and Z axes travel 660mm x 610mm x 610mm on linear roller guideways, while the AX450's X, Y, and Z axes travel 760mm x 610mm x 560mm. The feed rate is 30m x 30m x 24m per minute on the X, Y, and Z axes for both AX320 and AX450. Both machines are equipped with 9/12 KW spindle motors and ISO40 spindle tapers.
The positioning accuracy of the A/C axis is 15/10 arcsecond and the repeatability accuracy is 10/5 arcsecond on both the AX320 and AX450, with cutting quality and accuracy maintained by coolers that confine headstock temperature within an acceptable range. Coolant is circulated through ball screws to minimize temperature variation.
Also, the AX family is equipped with Heidenhain iTNC530 control units to assure high working precision of the 10,000rpm direct drive spindle. Aided by a tool center point management (TCPM) mechanism, the iTNC530 automatically corrects the tool path based on machining geometry and tool length, and compensates for 3D tool radius.
Dynamic collision monitoring (DCM) enables trial runs to minimize downtime due to collisions.
The Heidenhain iTNC530 control system provides online monitoring.
BX-model machines are suitable for machining precision molds as well as complicated parts for aircraft and medical equipment.
The AX320 and 450 feature an intelligent design that allows complicated workpieces to be finished in a single setup. This boosts machining efficiency and accuracy, as well as minimizing idle time.
Pinnacle GM Allen Hsieh says the company soon plans to introduce yet another new family of machines, the CX series of double-column CNC machining centers featuring a five-axial-travel spindle head.
Hsieh's company generates about 80% of its turnover from CNC machining centers and 20% from milling machines and CNC turning centers. “CNC machining centers are the most versatile among these machines,” the GM comments. “The automotive industry used to be the only user of CNC machining centers, but in recent years operators in the aircraft, green energy, 3C (consumer electronics, computers, and communications), and medical equipment industries have come onboard.”
Higher Technology Brings Bigger Margins
The company's CNC machining centers include vertical machining centers, 5-axis machining centers, horizontal machining centers, and CNC double column machining centers. “Five-axis machining centers are generating ever-higher profits for us, because these machines demand higher technology than three-axis and four-axis units and so command higher margins,” says Hsieh.
The company's latest machines target high-end markets in Germany, Russia, Turkey, India, Brazil, Eastern Europe, and Southeast Asia. “Our high price/performance ratio lures buyers in these markets away from the pricier, western-made products at a time when austerity in the current downturn is a priority,” Hsieh notes.
Pinnacle Machine Tool posted a sales growth of 40-50% last year, thanks to strong orders from high-end markets. Its annual sales growth target for the next few years is 20%. Although mainland China is the biggest export destination for Taiwan-made machine tools, Hsieh stresses that the recession there has not caused him much pain since only 5% of his revenue is generated in China.
A CE- and EMC-certified manufacturer, Pinnacle has targeted the developed economies as its primary markets. According to Hsieh, the company is drumming up OEM/ODM orders in the United States and promoting its branded tools in Europe, despite the fact that Germany is the world's foremost maker of machine tools.
Hsieh reports that Pinnacle began pushing into the European market around three decades ago, when it was still a manufacturer of traditional CNC milling machines. “In the beginning,” he recalls, “we showed up there as a contract manufacturer, but now we promote the ‘Pinnacle' brand. This is feasible because of our high price-performance ratio and the sagging competitiveness of the European machine tool industry.”
The maker's competitiveness is founded on its application software group, which is made up of experienced engineers who develop new programs using facilities that include CAD/CAM/CAE software and Finite Element Analysis. “Also,” Hsieh continues, “our reliable partnerships with dealers keep us well informed of the latest technologies and market trends, assuring that Pinnacle products remain popular.”
To overcome the perennial problem of talent shortage, Pinnacle provides apprenticeship programs in cooperation with several colleges, including the National Chin-Yi University of Technology and vocational schools near its Taichung headquarters. “A shortage of manpower is a headache for Taiwan's machinery industry,” the GM explains, “because mechanical engineering graduates tend to work in the electronics industry because of the bigger bonuses offered there, so we work with nearby schools to fill engineering vacancies.”
Pinnacle has managed to rein in the problem of material management that plagues machine-tool manufacturers by simplifying specifications for axial guideways and parts through “common or shared specifications.” “For instance,” Hsieh explains, “guideways come in 500mm, 600mm, 800mm, one meter, and 1.1 meter lengths. Stocking all specifications incurs extra cost, so we try to specify one length for two similar guideways to reduce cost--though this kind of shared specification must be acceptable to customers.”
