Multi Head Spindles : Old technology but still highly productive

Multi Head Spindles typically comprise two generic types as either i) small taper mounted mini gearbox driven units designed to be used with a conventional single spindle CNC machine. Typically useful for auxiliary operations or where the user requires maximum flexibility or used as a single spindle speed increaser or ii) a larger dedicated multi stage precision gearbox driven from a single input shaft through a secondary gearbox before splitting into multiple pitched individual spindles comprise sometimes in groups of spindles in excess of 24 pieces driven at relatively low speeds  less than 1500rpm in parallel. In most cases this type of work is used for high volume production of automotive components with engine head and block being the most common for drilling and tapping of aluminium or cast iron components. The technology has fallen slightly out of favour in recent decades due to the advent of high speed single or twin spindle CNC machines with tool changing capability as a standard machine. This type of next generation standardisation allows automotive customers to have mixed model production and flexibility on the introduction of new component modifications or variants but it does require a higher floor space and possible initial investment in the first phase.

  

  

Picture of modern CNC machining lines using single or twin spindle technology

 

Recent investments of modern CNC machinery in automotive manufacturing plants have typically been of the newer type not utilising dedicated multi head spindles but a substantial installed base remains amongst older plants in OEM's as well in the 1st and 2nd tier supply chain. Kuroda Jena Tec possesses unique design and multi head spindle capability  (From it's Systematic both in terms of design, manufacturing as well as repair of existing older designs of multi head. This includes the ability to reverse engineer critical spare parts that may no longer be available commercially from the original supplier. This becomes extremely important where multi head spindle gearboxes and sub spindles utilise special gear pitches, seals and bronze bushes which are normally of a non-standard type. Kuroda Jena Tec can therefore provide and stock spare parts packages also to support planned or reactive repair work.

 

 

Examples of new multi head spindles able to be provided by Kuroda Jena Tec

As always in the repair business, capability and speed of response is critical and Kuroda Jena Tec prides itself on the ability to provide its customers with a high standard of reactive service particularly in the automotive sector. Where engineering projects are required perhaps for the planned upgrade to a new component modification, Kuroda Jena Tec also possess the design and manufacturing competence to analyse the engineering component with the customer to design a new spindle head where required, manufacture, assemble, test and assist customer with the on-site integration and machining trials. 

  

Example of emergency breakdown work performed by Kuroda Jena Tec for a leading automotive OEM

For more details on how Kuroda Jena Tec can supply your requirements please visit our websites on www.jena-tec.com  www.jena-tec.co.uk www.jena-tec.de 

Kuroda Jena Tec : We Make Other Stuff Too!

Kuroda Jena Tec is increasingly known as a manufacturer and supplier of linear products for high precision ballscrews. However what is less widely known is the full range of high quality components for the machine tool and automation manufactured by the Kuroda Jena Tec group globally summarised below.

Motorised and belt driven spindles are designed and manufactured in our UK facility and provided globally to high calibre machine tool customers for grinding, milling, turning applications. An experienced and established design team works with OEM customers to meet the exact customer design specification. Utilising precision grade bearings spindles can be offered in a variety of round body or prismatic housings up to 100,000rpm with numerous additional technical features including ATC, Through spindle coolant, HSK, ISO, BT tool interfaces. Design and manufacture of multi head spindles for transfer lines remains a core competence of the UK team as well modular grinding heads for use on VTL’s or turning machines to grind complex components. Specifically related to the UK, Kuroda Jena Tec is the exclusive distributor of GMN spindles in the UK and Ireland and provides sales and service support for this popular and high quality German range.

Precision Gauges - Since its founding in 1925, Kuroda Precision Industries Ltd. has continued to advance with the history of gauges in our country, and has been striving for improvement in the product quality and reliability. As a result, Kuroda Jena Tec has successfully received the highest class evaluation as a pioneer of gauge manufacturer, such as an authority to indicate JIS "Grade 1" thread gauge mark for the first time in Japan and a production license for API gauges first time ever in the East. The importance of gauges has been recognized anew, because they play a significant role in quality control and quality assurance and the traceability of measurement has become a necessary condition in the quality management system represented by ISO 9000 Series in recent years.

As an authorized company for length section calibration, Kuroda Jena Tec believes firmly that it will be of service to the establishment of traceability of customer's measurement equipment to the national standard through the calibration and certification of gauge blocks and other various gauges as well as measurement equipment. In addition, our ultra-precision machining technology accumulated through the development of gauges is the essential technology contributed to the expansion of all of KURODA's products, and this technology is efficiently employed in tooling, precision grinding ball screws, pulse encoders, CNC surface grinding machines, super polishing machines, surface profile measuring systems, precision press dies, etc. Spindle Test Bars - Kuroda Jena Tec’s range of precision gauging also allows our Japanese production facility the capability to produce high quality spindle test bars in HSK, ISO or BT taper interface.

MQL Systems - Kuroda Jena Tec manufacture MQL systems in Japan and supply to leading global machine tool manufacturers. MQL as an acronym (Minimum Quantity Lubrication) is becoming slowly more understood in the machine tool industry as its clear technical and cost benefits start to be delivered for users looking to reduce consumption costs and improve technical and environmental factors for their machining processes. Previously MQL had limited applications and was frequently associated with specialist processes such as turning or specialist mould and die finishing with ball end-mill applications. MQL utilises a soluble and/or bio-degradable cutting oil delivered in a fine mist to the machining area via either externally delivered nozzles or via integrated tooling to the work piece. It is used as an alternative to either dry machining where tool life is reduced or in place of high pressure flood coolant. Firstly, the disadvantages of flood coolant are numerous such as the high running cost of coolant pumps, maintenance of coolant systems, cleaning of the work area of the machine tool and particularly in summer or warm conditions the unpleasant odour sometimes emitted by poorly maintained coolant systems. It is probably a common viewpoint in the machining industry that a frequent observation of machine shops using flood coolant require a high level of maintenance not only in monitoring coolant condition but also clearing up spills from leaks and so on that present a health and safety hazard in the work place.

While therefore it would be ideal to implement dry machining the effect on tool life, heat management and process performance means that this is not possible in most cases. Where dry machining is successfully employed, the process performance can be inhibited by the need to balance productivity against surface finish and tool life and maintenance costs. Therefore even where users have a defined dry cutting process, MQL can potentially assist with extending tool life and increase machining performance in terms of surface finish, cutting forces and process capability. Inverter Drives - As a spindle manufacturer, Kuroda Jena Tec is also frequently asked to package spindle inverter drives and supply a package of components to the customer. With in-house electrical design capability, Kuroda Jena Tec UK provides a complete design, supply and commissioning service for inverter drives systems related to precision motorised spindles. This is particularly useful when considering a modular grinding attachment or retrofit and modernisation of a machine tool. Kuroda Jena Tec can therefore provide a complete solution for your retrofit installation.

Hydraulic Work Holding - One of the major challenges in machining operations is the ability to clamp and hold workpieces reliably and repeatedly. Kuroda Jena Tec in Japan have over 20 years design and production experience providing hydraulic clamping utilising thin walled expanding shells to clamp components with 1 micron repeatability. Typically used in grinding operations the constant hydraulic pressure reduces workpiece distortion avoiding twisting or buckling once the workpiece is released.