IDA-72 External Components

Here is the rig laid on its back. Shown is the harness, and the valve block for the previously mentioned flush and demand modes laying on top. The rig is rather large, and the attached top carrying-handle is a nice feature for handling the rig.

Details of the chassis show that the exhaust valve is located at a position just at the centroid of the divers lungs. The exhaust gas is ported to the interior of the rig where it escapes through a series of large perforated holes in the cover. We can see the belt-valve block as well in this photo. Shown are the two selector-valves. These must be lifted about 1/4 of an inch before they may be moved, and then flip through about 120 degrees of arc. Their functions are described later.

Here is the unique belt-block. As you can see, it is fed with a gas-line and two lines run back to the rig. One simply purges the loop, offering a high-flow bypass of the internal mass-flow orifice. The other drives a pneumatic piston in the plenum chamber of the rig. When this valve is activated a piston moves about 1/2 inch and breaks the loop into two halves, thus making the rig an open-circuit system. The diver inhales from the auto-add valve and exhausts into the water through the normal exhaust valve. This instant conversion mode of the rig from a rebreather to an open-circuit system is VERY clever. More details will follow.

The rig was designed to be used in it's normal mode from a surface or bell supplied umbilical. This connection on the left side is the umbilical feed, which in this photo is capped with the white dust-cap. Also shown is the overpressure relief valve which would prevent an inadvertent high-pressure feed to the rig from causing any damage.

The bottom of the chassis is protected by this heavy-duty bumper, which takes the weight of the rig when the diver is dressing. This is a nice feature, and one that other manufacturers would be wise to emulate.

Yet another view of the top of the rig, with the inhale and exhale ports protected by their white plastic dust-caps. The exit for the three hoses running to/from the belt-block are shown. The hose on the lower right corner of the rig (covered by the plastic bag) is a hot-water hose for heating the divers breathing gas. The rig was internally fed with hot-water (also used for the divers suit) and a portion of the water is fed into a sheath surrounding the divers breathing hoses to keep his gas warm, in order to prevent hypothermia when using Heliox at extreme depths for long durations.

Electrical wiring? This is the connector that is hooked to the divers umbilical to send a telemetry signal to the surface if the rig lost umbilical supply. This would allow the surface controllers to determine the casualty to the system. In addition, an audible sonic-signal is made to the diver. Next to the cable exit is the battery door for the system, and under than the internal cylinder valve. The bottom bumper is well seen also.

Here is the lid of the rig, with the bottom shown towards the camera. There is no doubt that it is properly perforated!

One of the perforations is for viewing the internal cylinder pressure gauge. Since the rig was not designed to be used from these cylinders on a normal basis, the gauge is for surface pre-dive checks only.

Back to the IDA-72 Main Page

	Here is the rig laid on its back. Shown is the harness, and the valve block for the previously mentioned flush and demand modes laying on top. The rig is rather large, and the attached top carrying-handle is a nice feature for handling the rig.
	Details of the chassis show that the exhaust valve is located at a position just at the centroid of the divers lungs. The exhaust gas is ported to the interior of the rig where it escapes through a series of large perforated holes in the cover. We can see the belt-valve block as well in this photo. Shown are the two selector-valves. These must be lifted about 1/4 of an inch before they may be moved, and then flip through about 120 degrees of arc. Their functions are described later.
	Here is the unique belt-block. As you can see, it is fed with a gas-line and two lines run back to the rig. One simply purges the loop, offering a high-flow bypass of the internal mass-flow orifice. The other drives a pneumatic piston in the plenum chamber of the rig. When this valve is activated a piston moves about 1/2 inch and breaks the loop into two halves, thus making the rig an open-circuit system. The diver inhales from the auto-add valve and exhausts into the water through the normal exhaust valve. This instant conversion mode of the rig from a rebreather to an open-circuit system is VERY clever. More details will follow.
	The rig was designed to be used in it's normal mode from a surface or bell supplied umbilical. This connection on the left side is the umbilical feed, which in this photo is capped with the white dust-cap. Also shown is the overpressure relief valve which would prevent an inadvertent high-pressure feed to the rig from causing any damage.
	The bottom of the chassis is protected by this heavy-duty bumper, which takes the weight of the rig when the diver is dressing. This is a nice feature, and one that other manufacturers would be wise to emulate.
	Yet another view of the top of the rig, with the inhale and exhale ports protected by their white plastic dust-caps. The exit for the three hoses running to/from the belt-block are shown. The hose on the lower right corner of the rig (covered by the plastic bag) is a hot-water hose for heating the divers breathing gas. The rig was internally fed with hot-water (also used for the divers suit) and a portion of the water is fed into a sheath surrounding the divers breathing hoses to keep his gas warm, in order to prevent hypothermia when using Heliox at extreme depths for long durations.
	Electrical wiring? This is the connector that is hooked to the divers umbilical to send a telemetry signal to the surface if the rig lost umbilical supply. This would allow the surface controllers to determine the casualty to the system. In addition, an audible sonic-signal is made to the diver. Next to the cable exit is the battery door for the system, and under than the internal cylinder valve. The bottom bumper is well seen also.
	Here is the lid of the rig, with the bottom shown towards the camera. There is no doubt that it is properly perforated!
	One of the perforations is for viewing the internal cylinder pressure gauge. Since the rig was not designed to be used from these cylinders on a normal basis, the gauge is for surface pre-dive checks only.