TS5000 Positive Displacement Valve

The TS5000 Rotary Microvalve is a self contained fluid dispensing valve capable of depositing small accurate shots down to 0.010" in diameter at rates of 5 or more per second. Fluids can also be accurately dispensed in continuous beads in widths that range from 0.010" to 0.050" at rates up to 4" per second. In all cases, dot, bead or both, accurate and repeatable dispensing can be accomplished in production.

The TS5000 valve is offered in an extensive array of configurations. Two motor sizes are available, 3 watt and 6 watt. The 3 watt motor is available in 3 different speeds. Three different pitch feed screws are available; 8, 16 and 32. The 16 pitch feed screw is available in a shallow thread version with the 3 watt motor for small shot precision. Hard chrome plated stainless steel or heat treated tool steel feed screws are available for dispensing abrasive materials. Plastic valve components are available where chemical compatability is an issue. The 6 watt motor valve is available in an encoder (servomotor) version.

The TS5000 dispenses fluid material with a positive displacement action that is based upon a rotary feed screw (auger) mechanism. Material is constantly present at the inlet of the feed screw and controlled rotation of the feed screw moves the material from the feed point to the discharge point. Discrete control of the forward and reverse rotation of the feed screw controls the amount of material discharged to the outlet.

The operation of the TS5000 valve is very straightforward. The reservoir barrel, filled with dispense material and mounted on the valve, is continuously pressurized under a positive head of low air pressure (between 4 to 12 PSI depending upon the viscosity of the material) to deliver a steady supply of material to the feed screw. The valve is lowered down down to a preset gap between the tip end and the substrate by customer supplied automation equipment and a timed DC voltage "signal" is sent to the motor. The motor drives the feed screw for the time required and delivers a shot of material out of the tip.

Actual material deposit is dependent upon adhesion of the dispense material to the substrate. Deposit of the dispensed shot is achieved by the Z motion (tip reaction) and/or by reverse action of the feed screw. When the motor stops, the unit remains in position for a fraction of a second (dwell) to allow the last of the material to flow out of the tip. After the dwell period, the automation equipment moves the TS5000 to the next position.

The TS5000 valve can be used to dispense fluid materials which range from medium viscosity adhesives/epoxies potting compounds (50K - 100K CPS), to heavy viscosity and filled pastes (100K - 400K CPS). The TS5000 dispenses fluid with a positive displacement action using an auger principle which creates very high pressure at the dispense hub.

The amount of material dispensed is determined by the following:

1. Motor speed.
2. Motor on time.
3. Feed screw configuration (determines flow rate).
4. Material feed pressure.
5. Dispense tip size.

The dot diameter/bead width is generally determined by the size (gauge) of the dispense tip and the gap between needle tip and the substrate. When the gap is decreased, the diameter and width increase.

Techcon Systems, Inc., 12151 Monarch Street, Garden Grove, CA 92841. Tel: 714-799-9910; Fax: 714-799-6804.