THK has extended its range of high accuracy SCR cross motion linear guides with the addition of two new small sizes of rail width, at 15 and 20mm. Developed to help machine builders and OEMs reduce design and assembly time and costs, the new sizes are especially suitable for use in compact automation and production systems, in applications ranging from printed circuit board manufacture to pack erection and handling. In essence, the SCR is constructed from four standard LM guides, arranged in two parallel sets that are mounted at right angles to each, providing motion in both x and y axes.

This fully integrated unit guarantees smooth and consistent motion at high speeds, with excellent levels of accuracy, typically to within 2um in every 100mm of travel, and provides an extremely stable platform on which to base linear automation systems.

The cross rail structure enables the new linear motion guides to make complex planar movements, in horizontal or vertical alignments, while the use of 45-degree contact angles ball to raceway ensures equal load ratings on each guide rail in the radial, reverse radial and lateral directions also using Caged Ball technology, means reducing operating noise and heat to an absolute minimum, while extending operating life to in excess of 40,000km without the need for maintenance.

One of the key advantages of the new SCR is the ability to allow machine builders and OEMs to specify and install one complete unit, which has been pretested to guaranteed standards, as opposed to the use of multiple and separate guides, rails and mounting blocks.

As a result, the new guides can significantly reduce both design and assembly times and, perhaps as importantly, eliminate the problems of misalignment that can occur when assembling linear guides to synchronise in x and y axes.

The SCR guides are available in varying accuracy grades, ranging from precision to super precision right through to ultra precision, and each is supplied with a choice of contamination protection devices, including end seals, double seals and scrapers.

The complete SCR family of guides now ranges from 15 to 63mm width rails, giving the capability of constructing automation systems for both lightweight to heavy duty applications.

Two new products from THK provide a unique and innovative set of solutions to help machine builders and OEMs in the packaging sector reduce design and assembly time as well as cost. In addition, the new products offer exceptional levels of accuracy and reliability and are virtually maintenance free, with extended an operating life. The new SCR linear motion guide has been developed as an integrated platform for enabling loads or packs to be moved and positioned quickly and precisely in x and y axes, such as might be found on pack feed and transfer systems.

The SCR is essentially constructed from SHS type THK LM guides, in single or parallel multiple sets, mounted perpendicular to each other to form an x-y table base.

The fully integrated unit guarantees smooth consistent motion at high speeds, is extremely accurate, typically to within 2um in every 100mm of travel, and provides an extremely stable platform on which to construct linear motion systems.

The cross rail structure enables the guideway to make complex planar movements, and use of THK Caged Ball technology ensures low variation in rolling resistance and long term maintenance free operation.

Using the SCR, packaging machine builders and OEMs can now specify one complete unit, as opposed to separate guides, rails and mounting blocks.

In addition to saving design and specification time, the new product also significantly reduces assembly time and eliminates potential problems of misalignment in the x and y axes.

The HMG multi-motion guide is a completely new and innovative carriage and rail production system, that can be used by OEMs and also for upgrading existing systems to reduce costs and increase productivity.

Typical applications include pack assembly or erection lines and pack filling and sealing systems.

Another THK innovation, the HMG system, comprises a series of modular track or rail sections with the load being carried on the latest specification THK linear guide platforms.

Track sections are available in a wide range of lengths, widths and straight and curved formats, enabling almost any configuration of production track to be constructed, with single or multiple carriages or blocks being used to move and position workpieces allowing variable capacity.

Typical track configurations are circular, U-shaped, L-shaped or S-shaped.

In each case, it is possible to make considerable savings in design and construction time and cost.

For example, a conventional rectangular production track typically incorporates a turntable at each corner to re-align pallets or workpieces; using the HMG system the turntable units can be replaced with a simple curved section of track, allowing linear motion carriages to move in a continuous path.

Similarly, several rails can be mounted in parallel, while heavier loads can be accommodated by using multiple rails or carriages.

Unlike traditional production track equipment, the HMG system uses purpose designed linear motion components to ensure that each carriage moves consistently and accurately regardless of the set-up of the rail.

This eliminates potential variations in tolerances between different sections of track and ensures a smooth, almost frictionless motion, with positional accuracy of within +/-0.1mm.

The HMG linear motion guides are robust, high performance units and are capable of being loaded in radial, reverse-radial and lateral directions, with a maximum static load rating of 66.7kN on a single carriage.

They are low maintenance and have a long operating life.

THK has launched what is believed to be among the world’s smallest linear motion guides. The new versions of its proven RSR guides have carriages or blocks that measure down to just 4.0mm in width, making them ideal for use in a wide range of miniature or precision applications, including electron microscopes, pick and place systems for electronics components, hard disk reading devices and medical equipment. The latest versions of the miniature RSR are now available in block widths ranging from 4 to 10mm and lengths from 6.2 to 17mm.

The new LM guides are suitable for use with maximum rail lengths from 10 to 18cm and have basic dynamic load ratings of 37 to 307N.

The RSR guides use a dedicated design, with the block running on precision ground stainless steel balls set into virtually frictionless raceways.

The balls circulate within the body of LM block itself, enabling a wide range of stroke lengths easily to be accommodated.

Unlike competing linear motion guides, the construction of RSR ensures that a maximum number of balls are carrying the load at any point in time.

This means that the system is capable of carrying relatively high loads perpendicular to the rail axis.

Wide block versions of the RSR are also available, increasing moment capacity, and all components can be supplied in stainless steel if required, for use in harsh environments.

THK has launched a new version of its QZ lubrication system for its LM guides. The new version of QZ has been designed to extend still further the service life and overall performance of guides in particularly demanding applications and now includes a window for checking lubrication levels and can be replaced without the need to remove the block from the guide rail. Incorporating a unique fibre net and baffle system that is heavily impregnated with oil, the QZ lubrication system provides a cost effective alternative to traditional methods and can be used in conjunction with the company’s range of caged ball linear motion products.

With standard lubrication methods, such as manual grease feed, lubrication must be carried out at regular intervals to prevent an increase in frictional losses that can lead to unnecessary wear and tear, and, as a result, the frequency of maintenance and potentially repair work, which is costly and time consuming and can result in expensive downtime.

The unique design of the QZ lubricator means that the fibre net ensures that the lubricant is applied when and where it is needed via a high density material that acts as an applicator that is in permanent contact with the raceways.

In this way, it compensates for the oil that it lost during use, thereby eliminating the need for regular maintenance.

The use of a QZ lubricator can typically increase the service life of heavy load (18.6kN) carrying linear motion guides by over 50%, and those carrying light to medium loads (up to 10kN) indefinitely.

In addition to cost and time savings, this can also be extremely beneficial in applications where the linear guide may be difficult to access, where even routine maintenance results in costly downtime.

As the lubricant is delivered in the exact required amount to the specific location, its use to replace forced lubrication systems can reduce the annual lubricant consumption by up to 98%, due to its ability to eliminate wastage and enable more effective lubricant use.

The internal flow control also helps to contribute to a cleaner operating and working environment, and as no excess oil is wasted, is environmentally friendly.

Now, the incorporation of the new window allows the lubricant level easily to be manually checked, without having to dismantle the entire unit within the machine.

In addition, the new version has been designed to be easily removed and replaced without the necessity of removing the entire block from the rail.

As a result, routine maintenance can be carried out quickly and easily, with minimal disruption to the workings of the machine.

The QZ lubricator can be used in conjunction with the new THK side laminated contact scraper, which protects the carriage or block assembly from contamination by particulates in any mounting orientation, increasing still further the protection of the guide.

Additional maintenance products include end seals, metal scrapers and laminated contact scrapers, providing complete protection from foreign matter.

THK has introduced a new generation of linear motion products that have the potential to change the face of practices within the surgical, dental, ophthalmic and healthcare industries. Developed for use in a wide range of medical and healthcare machinery, from operating tables to servo electric hands for artificial limbs to eye treatment centers, the latest products have been designed to offer exceptionally high levels of positional accuracy and reliability, combined with a long, maintenance-free working life. One particularly innovative application is the use of a THK linear motion guide in a machine that produces glass pipettes for medical purposes, such as genetic engineering.

The use of the LM guides enables the fully automatic production and polishing of pipettes with openings down to 0.8mm in diameter.

Another application of this latest technology is the use of THK LM guides in a therapeutic training unit for the leg muscles.

The training weight can be adjusted between 2.5 and 150kg, while the linear motion systems allow the back of the foot rest to be adjusted in small increments, as well as the longitudal movement and headrest adjustment.

The high load capacity yet small dimensions of the linear motion system allow for a compact machine that also provides ultra smooth and gentle movements without sticking.

Compact and lightweight, the latest linear motion products offer outstanding levels of performance, functionality and reliability.

As a result, the use of these latest devices allows manufacturers to make considerable savings in both construction and maintenance costs, while improving the ease of use as well as operating efficiencies.

Furthermore, these innovative products are capable of providing ultra smooth and quiet movement, while being capable of transporting exceptionally high average dynamic loads with an exceptional degree of accuracy and precision.

To improve functionality and reliability still further, many of these latest products feature THK’s ground breaking Caged Ball technology, which eliminates the problems of noise, friction, particle emission and wear associated with conventional ball race configurations, by enclosing high precision steel balls within a separator cage, with controlled density grease pockets surrounding each ball.

This effectively prevents contact between the balls during operation, leading to significant improvements in both overall performance and operating life, and to quieter, cleaner, smoother and higher precision movement, with a far longer service life than traditional ball raceways.

Perhaps most importantly, THK’s Caged Ball technology enables linear motion systems both to be used in a far wider range of applications, and to become fit and forget products, enabling machine builders and end users to benefit from considerable cost savings, in terms of both labour and materials.

Furthermore, THK’s latest models have been constructed using stainless steel, further protecting the rugged units from any potential damage caused by moisture, as well as ensuring excellent wear resistance still further.

Additionally, the new devices are available with contact scrapers for applications where an additional level of contamination control and protection is required.

A range of accessories are available to enhance the performance of these latest linear motion devices still further, including the QZ lubrication system, that gives significantly extended maintenance intervals with reduced usage of lubricants.

THK, the leading global designer, developer and manufacturer of linear motion solutions, has announced the latest results from its ongoing program of research and development into linear motion technology. In particular, the company has expanded still further the parameters within which linear guides and actuators can be used, with prototype systems that can resist a range of temperatures and vacuum conditions that are considerably higher than anything previously achieved. The focus of THK’s R and D program is to evolve a new generation of linear motion technology that can be used both in the most extreme operating conditions, such as in the offshore and defense industries, and in mainstream manufacturing and process applications in order to make dramatic improvements in reliability as well as reduce operating costs.

The new prototype systems incorporate a range of new and unique properties and capabilities, including the ability to operate reliably at vacuum pressures down to 10e-3Pa or at sustained temperatures in excess of 200C.

These properties have been achieved by the use of the latest high performance steels and alloys, specially developed vacuum greases, with minimal emission characteristics and perflouroelastomer seals that are capable of withstanding both chemical attack and extreme environmental conditions.

To improve functionality and reliability still further, many of the prototypes feature THK’s ground breaking Caged Ball technology, which eliminates the problems of noise, friction, particle emission and wear associated with conventional ball race configurations, by enclosing high precision steel balls within a separator cage, with controlled density grease pockets surrounding each ball.

This effectively prevents contact between the balls during operation, leading to significant improvements in both overall performance and operating life, and to quieter, cleaner, smoother and higher precision movement, with a far longer service life than traditional ball raceways.

Perhaps most importantly, THK’s Caged Ball technology enables linear motion systems both to be used in a far wider range of applications, and to become fit and forget products, enabling machine builders and end users to benefit from considerable cost savings, in terms of both labor and materials.

Space and cost savings, enhanced precision and outstanding reliability are among the key benefits that innovative linear motion products from THK, the world’s largest dedicated developer of linear motion technology, are delivering in a wide range of printing-industry applications. Underpinning these benefits, in application areas from prepress to finishing, are linear motion guides based on THK’s proven and industry-leading Caged Ball technology. This innovative technology allows the company’s products to combine smooth, silent motion and high levels of positional accuracy, with exceptional load-bearing capacity and long, maintenance-free working life.

Caged Ball technology also means that, for a given load capacity, THK guides are smaller and lighter than their conventional counterparts.

Among the many examples of the use of THK products in the printing industry are plate making machines fitted with type SSR radial guides, which are designed for long life in high-speed applications.

The SSR guides provide smooth movement and low variation in rolling resistance, guaranteeing the high positional accuracy needed for the dependable operation of the machines.

In gravure printing machines, type SHS four-way equal-load guides have displaced an earlier solution for turner bar register adjustment, which used no fewer than 16 precision bearings at each station.

The new arrangement reduces costs by approximately GBP 500 per station and, since each machine has a minimum of 16 stations, this translates into substantial overall cost savings.

In the post-press sector, type SHS guides are being used in bidirectional board-cutting machines, where their smooth motion and rigidity are important benefits, and where their small size has allowed a space-saving design to be developed for the machine.

Knife-cutter machines are also being enhanced by the incorporation of THK products.

Type SSR guides are allowing the operating speed and, therefore, throughput to be increased by as much as 20% compared with machines designed around conventional ball bearings.

In addition, the machines operate more smoothly, and can run for longer periods without the need for maintenance

THK has introduced its latest range of linear motion products for use in a wide range of food and vending machinery, from soup dispensing to sushi making equipment. In particular, the latest products have been designed to offer exceptionally high levels of positional accuracy and reliability, combined with a long, maintenance-free working life. Compact and lightweight, the new generation of linear motion products offer far greater levels of performance, functionality and reliability than the products traditionally used.

As a result, the use of these latest devices allows manufacturers to make considerable savings in both construction and maintenance costs, while improving the ease of use as well as operating efficiencies.

Furthermore, these innovative products are capable of providing smooth and quiet movement, while being able to transport exceptionally high average dynamic loads surpassing known levels of accuracy and precision.

To improve functionality and reliability still further, many of these latest products feature THK’s ground breaking Caged Ball technology, which eliminates the problems of noise, friction, particle emission and wear associated with conventional ball race configurations, by enclosing high precision steel balls within a separator cage, with controlled density grease pockets surrounding each ball.

This effectively prevents contact between the balls during operation, leading to significant improvements in both overall performance and operating life, and to quieter, cleaner, smoother and higher precision movement, with a far longer service life than traditional ball raceways.

Perhaps most importantly, THK’s Caged Ball technology enables linear motion systems both to be used in a far wider range of applications, and to become fit and forget products, enabling machine builders and end users to benefit from considerable cost savings, in terms of both labour and materials.

Furthermore, THK’s latest models are evolving, with new materials, as well as stainless steel, further protecting the rugged units from any potential damage caused by moisture, as well as ensuring excellent wear resistance still further.

Additionally, the new devices are available with contact scrapers for applications where an additional level of contamination control and protection is required.

A range of accessories are available to enhance the performance of these latest linear motion devices still further, including the QZ lubrication system, that gives significantly extended maintenance intervals with reduced usage of lubricants.

The latest linear motion guides from THK are delivering major advances in the reliability and performance of woodworking machines, as well as offering significant cost savings in many cases. Transforming applications as diverse as carcass presses for kitchen cabinets and adhesive applicators for laminate foils, THK’s linear motion guides feature the company’s proven, industry leading, Caged Ball technology. This innovation eliminates ball-to-ball contact, while ensuring that lubricant is retained, resulting in minimal frictional losses as well as smooth, silent and virtually maintenance-free operation.

The Caged Ball system also permits the size and weight of the guides to be reduced without compromising performance, allowing the guides to provide exceptionally long service lives, even in high-speed applications.

The wide range of accessories available for THK guides offers further benefits in woodworking applications.

These products include seals and scrapers to mitigate the effects of wood dust and other contaminants, and the QZ lubrication system which further extends maintenance intervals and minimises the consumption of lubricants.

The QZ system and standard seals and scrapers can ultimately be enhanced by THK’s LaCS laminated contact scraper systems to ensure even the smallest of particles are defended from entry to the rolling elements.

With low maintenance an essential requirement in wood working applications, the QZ and LaCS system is being used successfully in kitchen cabinet presses, together with type SSR radial guides for the z-axis motion, and type SHS high-capacity four-way equal-load guides for the x-axis motion.

Type SHS guides are also being used in board stackers and palletisers.

The operation of these machines has to keep pace with the production line, making the dynamic performance offered by the guides of particular importance.

Their low maintenance requirements translates into reduced running costs for the machines, while the low friction of the guides is producing significant energy savings.

With noise levels an issue in the design of a new general-purpose woodworking machine driven by linear motors, SHS guides, with their near-silent Caged-Ball construction, are providing the solution.

As in the previous cases, long-term maintenance-free operation is proving to be an important bonus.

Compact Caged Ball LM Guides are revealing themselves to be an ideal choice for laminate foil applicators, offering greatly increased maintenance intervals.

The smooth, accurate motion of the guides means that the adhesive used on the foils can be applied more thinly, without risking dry spots.

Adhesive consumption is therefore being reduced, along with the risk of adhesive spill from the foil during application.

Manufacturers of linear motion products regularly publish comprehensive specification and performance data in product catalogues and technical literature. Although many of these figures, including dimensions, operating speeds and nominal lifetimes, are self-explanatory, there are many that are far from straight forward.

Unsurprisingly, end users don’t always fully comprehend how product specifications are calculated or how to interpret these all-important statistics in real-world applications.

In the realm of linear motion guides, product specifications usually relate to one of two types of technology.

Generally, linear motion guides rely on rails, or raceways, and guide blocks, or transport platforms, along specified routes.

Various techniques are available to support the mechanism, although most systems utilise steel ball bearings held within the block running along a groove profile in the rail.

The result is a highly efficient unit that provides accurate movement and pinpoint control.

Advances in technology have, however, encouraged relatively recent and dramatic developments in linear motion systems.

THK’s Caged Ball design, for example, which relies on lubricant-compatible retainers to hold the ball bearings at an equal distance from each other, has enabled smoother movements, less friction and fewer maintenance requirements.

The latest linear motion guides offer extraordinary performance levels encompassing operating speeds exceeding 300m/min and systems that travel in excess of 40,000km without maintenance.

Other statistics, including product dimensions and ratings, provide crucial product information without which correct specification would be impossible.

Nevertheless, some specifications can appear superfluous even if they provide important insights into the potential use or application of a product.

One principal criteria is dynamic load ratings (C), which are used to determine the service life of a linear motion system in response to a specific load applied from above (radial), below (reverse-radial) or from the side (lateral).

Linear motion guides can be divided into two main categories; those which have the same load rating regardless of where the load originates from (four-way equal-load type) and those specifically designed to support radial loads (radial types).

Another key measure is the static safety factor, which measures the relationship between the load-carrying capacity of a linear motion guide and an external force resulting from vibration or an unexpected impact.

In a busy factory or processing environment, this figure (fs) can reveal the ability of a linear guide to cope in particularly harsh operating conditions.

It should be noted that selecting a linear guide that can bear the maximum possible load when it is both stationary and in motion is vital to ensuring effective and accurate movements.

Likewise, data relating to radial clearance can be used to specify products and ensure that precision, performance and rigidity are maximised.

The data are subdivided into normal clearance, where the loading direction is fixed, impact and vibration are slight and axes are installed in parallel, and negative clearance, which relates to more specific applications, such as high-precision or heavy-loads.

Negative clearance is further subdivided into Clearance C1 (light preload) and Clearance C0 (moderate preload) and is determined by the internal load (preload) exerted on the rolling elements to increase block rigidity and reduce clearances.

In the present economic climate, information about life cycle costs is often the defining consideration.

Fatigue life refers to the total operating distance that a linear motion system travels before its internal metal surfaces start to deteriorate or flake.

Yet, the service lives of similar systems manufactured to the same specifications and subjected to the same operating conditions can and do vary.

Therefore, a guideline for determining fatigue life is the nominal life, which is the total running distance that 90% of a series of identical linear motion systems can achieve without deterioration, under the same load conditions.

To fully appreciate the relevance of these product specifications it is often useful to compare differing technologies.

Endurance tests, which push linear guides to their absolute limits, are used by manufacturers to establish accurate product information.

These tests involve a series of repeated movements that replicate extended use within certain performance parameters.

Often carried out on life-test machines that are designed to evaluate a number of linear motion guides at any one time, these tests form the basis of most product specification data.

For instance, a series of tests on THK’s SHS linear motion guide have revealed that when carrying 50% of its dynamic load capacity, the Caged Ball product travelled 1347km with only its initial lubrication.

This compared favourably to its full-contact equivalent, which only completed 420km before flaking.

It should be noted that the conventional guide also required lubrication every 100km.

These results, and those from similar tests on other guide types and sizes, represent many years of testing and indicate that the Caged Ball design has a greater dynamic load rating than initially calculated.

Indeed, THK has recently revealed that tests carried out at its research facilities in Japan indicate that the Caged Ball design provides a greater service life than conventional full-contact systems.

THK has consequently increased its initial dynamic load ratings, measured in kilonewton units, by 30%.

In terms of fatigue life, this equates to over double the life of conventional systems.

The intricacies of linear motion guide specification reflect the important role played by these components in complex industrial, manufacturing and automotive processes.

They are required to operate quickly, accurately and smoothly, often completing many hundreds of tasks each day.

Detailed product information allows specifiers to select the most suitable product, thereby realising a system’s full operating potential.

Product specifications are the guiding lights in the dark and often complex world of procurement.

They outline a system’s capabilities and indicate where its limitations lie.

They are the unequivocal truths that determine which linear motion technology to opt for.