Fisnar DC200 Epoxy Dispensing Machine
*Update* The DC200 has been discontinued and replaced with the DC100 MAX. Request a quote today.
TRANSCRIPT:
Epoxy is a “Critical Component” of any fiber optic cable assembly. Controlling the amount of epoxy dispensed into a connector is essential to producing high-quality, long-lasting cable assemblies. Dispense quantity control is inherently difficult when injecting manually: the dispense quantity depends on the skill and experience of the operator. The DC 200 from Fisnar automates the injection process by removing variables associated with manual injection, providing consistent and accurate epoxy dispensing, and resulting in high-quality reliable terminations.
The Fisnar DC 200 digital dispensing system is pneumatically operated with compressed air connected to the back (100 psi max) and operated with a foot switch. Depressing the foot switch allows the air to pass through for a programmed amount of time and a programmed amount of pressure.
We are going to fill a syringe barrel with mixed epoxy and attach it to the DC 200-barrel adapter. Once we depress the foot switch, pressurized air will fill the barrel pushing epoxy out the syringe needle. By controlling the pressure and time applied, we can control the amount of epoxy that is dispensed. The screen displays which user-defined settings profile has been selected, which of the five dispensing modes is currently active, and several dispensing parameters. Users can customize and save up to ten user-defined settings profiles. The appropriate dispensing mode depends on your particular application, the type of epoxy being dispensed, and other factors. We will discuss in more detail later in the video.
For this demonstration, we are using ÅngströmBond AB 9320 Epoxy in a 2.5-gram bipack, but any epoxy will work in the dispenser. Different epoxy types vary in viscosity and pot life and may require different dispenser settings than shown here. We will prepare the epoxy per manufacturer’s recommendations. The epoxy is transferred from the bipack into a syringe barrel and degassed in a centrifuge. Insert a plunger into the barrel and connect the barrel to the DC200 barrel adapter. Note that syringe barrels come in a variety of sizes and it’s important to ensure you order the proper size barrel adapter for the syringe you want to use.
Now we remove the syringe cap and install the dispensing needle. Needles come in a variety of shapes and sizes depending on your dispensing needs, in this demonstration we are using an 18-gage stainless steel needle, which is very common for fiber optic connector applications.
Since the new needle is completely empty of epoxy, it’s always a good idea to take a few preliminary shots to bleed out any air and fill the needle with epoxy.
When the footswitch is activated, pressure flows into the syringe body, dispensing a certain volume of epoxy. We can adjust the dispensed volume by adjusting the pressure and time applied.
When first developing a process (the optimum time and pressure settings for your application) some experimentation is necessary. This demonstration uses an 18-gage needle to fill a standard SC connector with AB9320 epoxy. We’ll need to determine the best time/pressure settings for this combination of variables. First, set the time and pressure to moderate values and try to fill a sample connector: insert the needle until it bottoms out, depress the foot switch until you see the epoxy bead on the ferrule surface, and then backfill the ferrule. Manually adjust pressure and time controls as needed, until you are satisfied with the dispensed results. Once satisfied these settings will be your starting point for future dispensing and should be saved. Of course, for different combinations of connector, needle, or epoxy types you’ll need to repeat the process to determine the proper settings.
At this point, it’s a good idea to record the diameter of one shot of epoxy on a flat surface. Use that diameter to create a “dot-size template.” A dot-size template is a printed grid of circles used to estimate dispense volume. Remember our starting time and pressure settings are rough starting points. Normal lot-to-lot variation in epoxy viscosity may result in more or less epoxy being dispensed - the operator can use the dot template to validate the dispense quantity for each new syringe of epoxy BEFORE starting to fill connectors for production. Simply dispense one dot per circle to make sure it completely fills the circle. Fine-tune the pressure and time controls until satisfied. In this case the dispensed volume agrees with the dot sizes, no adjustments to time and pressure are needed, and we can begin to fill connectors.
Now we are ready to start injecting connectors for production. Insert the needle until it bottoms out inside the connector. Maintain pressure on the needle and connector while depressing the foot switch. You will see a bead of epoxy on the end face when the ferrule hole is filled. Release the connector and press the foot switch again. This will backfill the connector (dispensing epoxy within the connector behind the ferrule).
The vacuum feature allows us to reduce residual pressure within the syringe between shots. This minimizes the excess flow of epoxy beading up on the needle tip which could cause problems when inserting the needle into the next connector.
The DC 200 gives you the flexibility to select a mode that works best for you. Choose from one of five dispensing modes based on your application, epoxy type and other variables unique to your product and process flow.
The Fisnar DC 200 has 5 dispensing modes. In Timed Mode, when we depress the foot switch pressure is applied for a preset amount of time. In Purge Mode, when we depress the foot switch pressure is applied constantly until we release the foot switch — the longer the foot switch is depressed the more epoxy is dispensed. In INT or Interval Mode, dispensing starts when the foot switch is depressed and ends when the foot switch is released OR the set time is released, whichever comes first. In Teach Mode, we will inject one sample connector first: depress the foot switch until the epoxy bead is visible and then release. The machine captures the time needed and all subsequent shots will use the captured time with each press of the foot switch. In Timed Plus Mode, we can pre-program increases to dispensing time to compensate for normal viscosity increases in the epoxy through its working life. For example, the operator can program the dispensing time to increase by a certain amount (in this example 1.5 seconds) after a certain number of shots (in this example 3 shots). After the defined numbers of shots have been dispensed, the pressure automatically increases.
Additional Functions Include:
- Unlock/Lock (to password protect unauthorized changes)
- Add Dispensing Time (for use with timed plus mode)
- Glue Alarm (gives a visual and audible alarm to operators when epoxy pot life has been reached - this may be useful with strict pot life or working life)
- Pressure Alarm (gives a visual and audible alarm when pressure thresholds have been exceeded)
- Vacuum Alarm (gives a visual and audible alarm when vacuum thresholds have been exceeded)
- Auto Purge (allows for automatic dispensing when the machine is idle. This may be useful to prevent clogging if using material that cures when resting.)
- Robot Alarm (Stops external equipment when alarm is triggered. Only used when external equipment is connected.)
- Power Switch (Allows power to be switched by external equipment, if connected)
- Dispense Count (Display the cumulative number of completed shots)
- Language (Choose between English or Chinese)
- Used Time (Displays the cumulative time the machine has been powered on.)
And finally, automated analysis, which provides objective, detection, support and visual assistance to identify defects, documentation of results and advanced data for analytics. Beyond just simple particle size, can include advanced parameters like total occluded area, particle geographical distributions, and other advanced ways to decide or determine cleanliness. The customer benefits and applications are clear, the ability to remove contamination early at the source improves production yields across the manufacturing process. It will eliminate costly component waste and optimizes performance results across the manufacturing line.
