1. Available Types
1. Room Temperature unmounted valve:
This is the simplest valves we make. The body is made of Stainless Steel. The valve dissipates about 8 Watts when operating at 600 Hz and some heat conduction means are required to keep the valve from self heating in the vacuum. Electrical vacuum feed-through for the current pulses as well as gas feed line into the vacuum are required. This valve can be operated at Room temperature. The two coil wires should be straightened, twisted and connected to a BNC vacuum feed-through (the twisted pair minimize loop area and reduce the inductance).
We can supply these valves with "wings" for mounting on rods to carry away the heat generated by rapid pulsing of the valve. The anchored contact protect the coil wires from damage during handling
2. Unmounted stainless body valve for High Harmonics Generation.
The shaped front flange allows the exciting laser beam to access the jet near the nozzle exit where the gas density is higher. This type of front flange can fit all types of valve we make, but need to be specified when ordering the valve (it has 4 tightening screws instead of the normal flange that contains only three such screws, thus these flanges are not drop in replacement for normal valves).
3. Unmounted Stainless valve for cryogenic operation.
This valve is similar in its appearance to the pictured room temperature valve. It differs by having a more efficient magnetic engine allowing it to dissipate less heat. The valve can be operated down to 60K with a proper cold finger. Wiring instruction are as in type 1 valve.
4. Unmounted Cryogenic valve:
The body of this valve is made of Copper (to operate down to 10K). It comes with a selected high efficiency magnetic motor to reduce the heat dissipated in its operation. It can be operated continuously from 10K-400K without adjustments. It is used to generate clusters of noble gases (even Helium droplets). Power dissipation is only 0.6 mJ/pulse.
5. High Temperature unmounted valve.
This valve comes with a built in Heater and a thermo-couple and can be operated at up to 250c. Some means to carry the heat away are required (usually through mounting posts connected to the "wings" and an outside facing flange. Electrical feed-through for the Coil, Heater and Thermocouple are required. There is an internal sample cartridge containing the material sample to be vaporized.
6. Fully mounted Room temperature valve:
This valve is mounted on a standard ISO-100 vacuum flange, with gas feed through and coil feed through. Efficient heat conduction from the valve to the flange is maintained by Aluminum support rods. The stand off distance from the nozzle exit to the support flange can be 100-180 mm long. Other flanges can be supplied.
The fully mounted valve proved to be more reliable in long term operation.
7. High Temperature fully Mounted valve.
fully mounted HT valves, for low or high temperature operation
This valve is mounted on an ISO-100 vacuum flange, and comes with all the required feed through (2 for the coil on a BNC connector, two for the heater wire (7 ohms resistance) and two Thermocouples connectors), one demountable gas feed through and several spare connectors for future use). Sample cartridge can be changed without removing the valve from its support structure and wiring. The combination of either Al or short Stainless columns inserts controls the heat dissipation to the mounting flange.
8. Mounted Cryogenic valve for low temperature operation and Temperature control.
This valve is mounted on a flange to fit a (commercial, customer supplied) cold finger refrigerator. It is made of Copper (Titanium Nitride coated to prevent oxidation), and can operate from 10K-400K. The fine temperature control (0.1K) required for reproducible cluster generation is achieved by two built in power resistors heaters. This mounting is recommended for Helium droplets generation. Temperature sensor ( A Si diode sensor, with a cryogenic temperature controller,not supplied) can be readily mounted on the copper valve . We recommend the use of "Lakeshore" cryogenic controller and diode sensor (not supplied by us):
http://www.lakeshore.com/products/cryogenic-temperature-controllers/model-335/Pages/Overview.aspx )
The recommended diode sensor that can be mounted directly on the valve is DT-470-MT-12-A
7. Manipulator mounting of the valve.
It is sometimes required to assemble the valve in a way to allow for alignment of the valve relative to a fixed laser beam (High Harmonic Generation, Laser Ablation Source etc.). We have developed a compact mounted valve assembly that, together with a re entrant design of a commercial port aligner, can achieve that simply and reliably, keeping all required electrical and gas connections, and heat dissipation on a single external flange. There are three elements in this design:
I. Commercially available port aligners:
These port aligners can be purchased from:
http://www.uhvdesign.com/index.php?op=template5&pid=107&ln=english .
II. The valve is mounted on a compact flange, on a re-entrant tube that fits the port aligner: We supply the flange mounted valve only, the other parts are supplied by the customer.
A rotatable view can be seen in ADOBE reader opening the attached file here. Dragging the mouse cursor will change the viewed angle.
