Cryogenic Cooler Adapter Plate

This invention is in the field of mounting devices for mechanical cryogenic coolers. These coolers each include a compressor portion (Stirling cycle or the like) driven by an electric motor, and an expansion or cold finger portion. As currently made, the compressor is mounted on one side of a mounting flange, with the cold finger extending out the opposite side of the flange. The coolers thus made are used for cooling infrared detectors of various night-vision devices, and are each mounted to such devices by sealing the mounting flange in an opening in the device. The sealing may be accomplished in various ways, such as by using o-rings between the flange and the device, or by using adhesives, etc. The instant invention arose because there was a need for an adapter that would allow a given cooler to be used with more than one night-vision device. In particular, the U.S. Army is currently using a cooler known as the "common module" cooler which is employed in various pieces of night-vision equipment. Unfortunately, some equipments have been designed which cannot use the common module without various different adapter plates. Having these different plates makes for supply and logistics difficulties. It is desirable to minimize the number of various different adapters needed, and this the invention does. Two specific examples of equipment with such different adapter plates are the tank thermal night (TTS) and the tank infrared sight (TIS) as used in the new MI tank. The instant invention is for a single adapter plate made with both TTS and TIS.

The invention is an adapter plate for mounting a common module cooler to either a TTS or a TIS. The adapter has on one side the proper alignment pins and screws holes for mounting on the surface of a TTS housing and different such pins and holes on th other side for mounting on a TIS housing. The common module has a mounting flange with a cold finger on one side and a cryogenic compressor on the other side. The flange is inserted into an opening in the adapter and the cold finger extends into the equipment housing. When used with TIS equipment, a retainer plate is used to hold the adapter plate to the TIS housing.

FIG. 1 is a pictorial view of one side of the inventive adapter plate.

FIG. 2 is a pictorial view of the other side of the invention adapter plate.

FIG. 3 is a plan view of a retainer plate for one use of the adapter plate.

FIG. 4 and 5 are partial sectional views the walls of the two thermal sights with which the invention is used. Those views are drawn to twice the scale of FIG. 1-3.

FIG. 6 is a side view of a cryogenic cooler with which the invention is use d

The invention may be best understood when this description is taken in conjunction with the drawings. FIG. 1 shows one side of the inventive adapter plate wherein reference numeral 10 designates the discoid adapter with irregular octagon (generally square) embossment 11. The adapter is pierced by center bore 12; inside this bore are o-ring grooves 13 and 14. In embossment 11 are bored and tapped holes 15; pins 16 extend outward from 11. Finally, shallow undercut 17 is formed in the face of embossment 11.

Referring now to FIG. 2, the other side of adapter 10 may be seen. On face 10a we see large aligning pins 20 and small aligning pins 21. Bored and tapped in 10a are holes 22.

FIG. 3 shows retaining plate 30 having central opening 31, small pin clearance blind holes 32, large pin clearance blind holes 33, and screw clearance holes 34.

FIG. 4 shows a sectional view of a wall portion 40 for a TIS. This view is taken through the center of circular opening 41 in 40 and is twice the scale of FIG. 1-3 to show its details better. Concentric with 41 is an irregular octagon (generally square) hole 42 to which embossment 11 of FIG. 1 corresponds. Also concentric to 41 is round hole, to which the diameter of adapter plate 10 corresponds. Wall 40 is bored with various holes, such as tapped screw holes 44 and guide holes 45.

FIG. 5 shows a sectional view of a wall portion 50 for a TTS. This view is taken through the center of circular opening 51. Screw clearance holes 52 are bored through 50; tapped holes 22 of FIG. 2 correspond to holes 52. Wall 50 is also bored for small alignment pin holes, only one being shown as reference numberal 52, and large alignment pin holes, only one be shown as 54.

Finally, FIG. 6 shows a cooler 60 with which the adapter is used. This cooler includes compressor 61 with base 62, mounting flange 63, and cold finger 64.

The adapter of FIGS. 1 and 2 may be used to mount cooler 60 to either the TIS housing wall 40 of FIG. 4 or the TTS housing wall 50 of FIG. 5. For mounting 60 to 40, one proceeds as follows: o-rings (not shown) are installed in grooves 13 and 14, and a seal (not shown) is installed in undercut 16; 10 is then installed in 40 such that embossment 11 fits into hole 42 and the remainder of 10 fits into hole 43. Alignment pins 16 extend into holes 45. Adapter 10 is held in place by retaining plate 30. This plate is placed onto 10 and 40 such that large alignment pins 20 of adapter 10 extend into clearance holes 33 and small alignment pins 21 of 10 extend into clearance holes 32. Screws (not shown) are inserted thorough screw clearance holes 34 into tapped screw holes 44. Flange 63 of compressor 60 is inserted through hole 31 of plate 30 into hole 12 of plate 10 forms a seal with the o-ring in groove 14 and the seal in undercut 16 presses against 40 and provides an air-tight seal. Although not shown, base 62 of cooler 60 is supported by and secured to a bracket or equivalent fixed to or forming a part of the TIS.

For mounting cooler 60 to wall 50 of the TTS, one inserts o-rings into grooves 13 and 14 of adapter 10. Adapter 10 is mounted to wall 50 such that small alignment pins 21 extend into small alignment holes such as 53, and large alignment pins extend into large alignment holes such as 54. The adapter is held to wall 50 by screws (not shown) extending through holes 50 into tapped holes 22. Flange 63 of compressor 60 is inserted into hole 12 of plate 10 and forms a seal with the o-ring in groove 13. As described above for TIS mounting, cooler 60 is supported by means not shown.