Dispensing Innovation - made in Germany

The heart of all marco dispensing systems beats fast, precisely and persistently. The drive of the marco Superior Jet dispensing valve and the range of modular valves allow high-precision, fast dispensing of a large variety of media with a tolerance of less than 1% of the dispensed volume.Example of the dispensing results for a UV-curing adhesive (2.000 cPs) :With marco’s unique piezo drive, the valves work fast and reliably, for both dispensing without contact (jetting) and contact dispensing(e.g. with a needle). In the standard configuration, dispensing frequencies up to 1,200 Hz can be achieved in continuous operation.marco guarantees a failure-free service life of 1,000,000,000 cycles. The high frequency and long service life lead to higher productivity and significant cost savings for the customer.The selection of suitable parameters and components results in a valve that can dispense volumes of 0.5 nL (0.6 µg at the corresponding density) and reach drop diameters down to 0.2 mm (trials conducted with an adhesive with a viscosity of 180 mPas). The valves can easily dispense adhesives in narrow spaces of 0.1 – 0.3 mm, an important feature for numerous applications in electronics manufacturing (underfill e.g.). With its modular design, the marco superior jet dispensing valve and the standard modular valves are perfectly adapted to our highly specialised systems. They communicate via RS485 bus technology with auxiliary devices such as heaters, pressure controllers, level sensors etc. The system’s easy handling, its versatility in meeting a large variety of dispensing requirements and the complete replaceability of all parts subject to regular wear, keep set-up costs, maintenance and overall cost of operation, to a minimum.Valve seat module for the Superior Jet dispensing valve and other modular valves:Superior Jet dispensing valve with dot counting function:

The valves and dispensing systems are controlled via touch screen monitors, available with a screen size of 7“ or 10“. Even complex systems are easy to operate with the user-friendly application software interface.The software provides a clear overview of all components and their current status.For more in-depth access to the operating system, the monitor provides a multitude of high-performance functions. All available parameters and data can be recorded and displayed (history function). A user-friendly program editor can store ten different dispensingprograms with up to 100 dispensing steps. A particularly helpful function is offered by the customizable opening and closing edges.Depending on the application, the dispensing process can be optimised to achieve best possible results.Many additional functions are available via the graphical user interface. Special menus provide comfortableand intuitive control for systems using hot melt,2K adhesives or filled media. Forty different systems can be controlled in parallel via one single terminal.10” System control centre:7” System control centreDriver boxAs a low-cost alternative, the valves can be controlled via a driver box. The driver box offers similar functionality to the touch screen monitor. Due to its compact design, however, it cannot compete with the easy and intuitive operability of the touch screen.

The Polyurethane hot melt system is designed for dispensing of reactive polyurethane-based hot melt adhesives. It is composed of a modular dispensing valve and a special tank for hot melt media with a capacity of 30 ccm. The system is divided into three heating zones to ensure optimum medium processing. The medium melts progressively as it passes through the zones of increasing temperature. Once it has reached the dispensing area, the medium is at the perfect temperature. This careful processing is further improved by the optional use of a desiccant cartridge to reduce contact with humidity. The media tank is fitted with an ultrasound based level measurement system which can determine both level and melting state of the medium.These features ensure high process reliability. Like all systems from marco's mts range, the Polyurethane Hhot melt system is a modular system. This modular design has a crucial advantage: all parts which are in contact with the medium can be removed, cleaned or replaced individually. The modular dispensing valve can be operated with a continuous dispensing frequency of up to 500 Hz to allow for high path speed when dispensing hot melt media, achieving line widths or dot diameters of 0.3 mm, depending on the adhesive.The Polyurethane Hot melt system is suited for applications in the field of electronics manufacturing.

The 2K Jet system contains one pump with one piston for each component A and B (ratio 1:1, 1:3, 1:10 and more, stepless), a mixing element and a modular dispensing valve. It is used to convey, mix and dispense (jet) two-component adhesives. Both components must be liquid and without fillers. All parts which come into contact with the medium can be replaced quickly and easily, the use of disposable mixing elements ensures a smooth process flow.A large variety of valve inserts are available for the 2K Jet system depending upon the application. Diameter or shape can be selected depending on customer requirements.The mtv/dpa/* pump with integrated position measurement system generates a feed pressure of up to 72 bar and allows precise volume monitoring of both components.The system comes with a 10” touch-screen terminal with user-friendly software for monitoring and visualisation.

For the filling of white LEDs two alternative systems mts/led/* are available. The system mts/led/w is composed of a modular dispensing valve and a media tank with a pneumatic pressure booster, the system mts/led/svwa contains a slider valve instead of the modular valve (see image). Adhesive with filler, usually a two component (2K) adhesive, is conveyed to the dispensing valve and applied to the LED. To make full use of the pot life of the 2K adhesive, it is filled into30 ccm cartridges which can easily be replaced once they are past their pot life. The cartridge is mounted horizontally and rotatable in order to avoid the sedimentation of the filler material in the cartridge.The mechanically generated pressure in the media tank, which provides up to 18 bar feed pressure, ensures there is no contact with air so that no gas is absorbed by the medium. marco uses a special piston to optimise pressure transfer to the fluid. A static mixer homogenises the medium once again as it passes through the fluid body, shortly before it is dispensed, ensuring sufficient mixing in the finished product to avoid light scattering and maintain constant and equal converter content. The mts/led/* system was specially developed by marco for use with highly abrasive media. The modular valve (system mts/led/w) does not close completely during the dispensing process. As a further advantage the slider valve system (system mts/led/svwa) is less vulnerable for abrasion due to the principle of the slider valve.The advantages of both systems are twofold: the product life increases due to less friction on the sealing seat and the filler particles are not destroyed.

Certain types of adhesive tend to absorb ambient gas or air when pres-sure is applied. During the dispensing process the gas is then released and bubbles form in the media. To avoid these negative effects, marco provides equipment preventing any contact between the medium and gas or air.A pneumatic high pressure pump is available for media which require a higher dispensing pressure. Depending on the type, pressure on the medium can be amplified by a factor of 3 or 12. For media dispensed in the standard pressure range, a special cap can be fitted on the cartridge.The cap has a piston which transmits the pneumatic supply pressure to the medium without contact to the compressed air.

Many marco systems boast a further useful feature: precise volumetric control. The position sensors in the media supply tank mounted either in the piston of the special cap or in the high pressure pump, provide an extremely precise reading of the dispensed volume. The direct correlation between dispensing parameters (cycles, opening time, supply pressure) and dispensed volume means the dispensed volume can be kept at a constant level over a long period even if the media properties change over time. The deviation tothe target volume does not exceed 1%. With media where viscosity increases over time for example, a readjustment of the opening time or of supply pressure will ensure that the volume set at the start of the process remains constant throughout the whole production shift (contents of one cartridge).