For manufactured products requiring the applications of industrial adhesives, paints and other liquids, high precision dispensers are employed to accurately dispense, inject, smear, or drip the substance in specific locations, typically as a point or in a line, circle, or arc. Adhesive dispensers are widely used in electronics, lighting, automotive, power generation and other industries; in fact, they are one of the most basic types of equipment found in product manufacturing.
However, this type of dispenser technology is far from mature in China, and international brands, whose products generally involve high purchase costs, have a clear monopoly. To help the Chinese overcome this, Advantech has worked with local smart equipment manufactures to aid them in realizing a technological breakthrough.
This client's dispensers had three servo motors and three stepping motors. This included an XYZ platform where the Z-axis is an XZ step axillary module and a step control feed axis where they key axis is geared to five other axes.
To accommodate different product heights, dislocation sensors were needed to scan the nozzle height via laser in order to establish dual Z-axis control of the nozzle height. Of particular importance, the dispensing rate and movement speed had to be consistent, thus requiring automated comparative triggers for the adhesive valves.
To meet high-standard industry requirements in terms of precision and speed, particularly given that products tend to be very small, sufficient control needed to be achieved to produce dispersion points as small as 0.15 mm in diameter, line application widths of 0.168 m, and straight angle turn radius of 0.5 mm, all of which need to be applied at speeds of up to 200 mm.s.
The workflow of the high-speed, high-precision dual-channel adhesive dispenser is divided into four stages:
- Material Loading
- Adhesive Application
At the material loading stage, the USB-4716 analog acquisition card and dislocation sensors are utilized for machine visual inspection, which involves calculating the PCB angle and height of the work piece. This data is used as inputs to adjust the adhesive dispensers' valves, a process that is handled by the PCI-1285. At the dispensing stage, the adhesives are applied to the PCBs according to the programmed specifications, for which the PCI-1285 is again utilized to execute interpolation and various other functions aimed at axis control. At the weighing stage, the USB-4716 analog USB module determines whether the amount of applied adhesive meets the specified amount.
Finally, work pieces reach the product completion stage when the appropriate amount of adhesive applied, at which point they are unloaded from the machine.
ACP-4340: 4U Intelligent Rackmount Chassis with 4 Hot-Swap Drive Trays
PCE-5129: PICMG 1.3 CPU card supporting 6th/7th Generation Intel® Core™ i Processor
PCE-5B12-07: 12-slot BP for 14-slot Chassis
PCI-1285: DSP-based 8-axis Stepping and Servo Motor Control Universal PCI Card
USB-4716: 200 kS/s, 16-bit, 16-channel Multifunction USB Module
PCI-1761: 9-channel Relay/8-channel Isolated Digital Input PCI Card
Of particular benefit to the customer, the PCI-1285's DSP structure allowed simplified system customization and control of the dual-channel adhesive dispenser. Furthermore, the PCI-1761 and USB-4716 ensured that high-speed and high-precision operation could be maintained in addition to allowing for future expansion while occupying minimal space.
This case shows that with the strong backing of a professional R&D team that is well versed in motor control algorithms and applications, Advantech can provide pre-evaluation, example code for development and on-site adjustment for our customers.