US 3673697 A
An attitude indicator having a circular, annular transparent tube containing a liquid, preferably colored, and a gas bubble, the tube being constructed for encircling and for being fastened non-rotatably upon the forearm, in a position perpendicular to the length of the forearm of a diver. The readily visible position of the bubble in the tube enables the diver to compare and determine instantly, at any moment, the angular attitude, with reference to gravitational lines of force, of the tube itself, the attitude of his forearm and body, and the angular attitudes of nearby structures and surfaces.
Description (OCR text may contain errors)
' United States Patent Wasson 1 51 July4, 1972  ATTITUDE INDICATOR 72 Inventor: Gene 3. Wesson, 1553 Gamon Road,
Wheaton, 111. 60187 22 Filed: m. 22, 1911 211' Appl.No.: 111,353
 U.S. CL ..33/348, 33/379, 33/370  Int. Cl ..G0lc 9/00  Field of Search ..33/206 R, 207 R, 212 R, 222 R,
 References Cited UNITED STATES PATENTS 2,344,241 3/1944 Flint ..240/6.44 2,871,573 2/1959 Schenker ....33/207 R 3,269,729 8/1966 Morrison ..33/2l2 R FOREIGN PATENTS OR APPLICATIONS 789,942 1/1958 England..." ..33/223 Primary Examiner-Leonard Forman Assistant Examiner-Charles E. Phillips Attorney-Frank .l. Foley [5 7] ABSTRACT An attitude indicator having a circular, annular transparent tube containing a liquid, preferably colored, and a gas bubble, the tube being constructed for encircling and for being fastened non-rotatably upon the forearm, in a position perpendicular to the length of the forearm of a diver. The readily visible position of the bubble in the tube enables the diver to compare and determine instantly, at any moment, the angular attitude, with reference to gravitational lines of force, of the tube itself, the attitude of his forearm and body, and the angular attitudes of nearby structures and surfaces.
As this indicator is intended especially for use where light is absent, or minimal, or obstructed by dark colored sediment suspended in the surrounding water, strong illumination is provided. A battery powered lamp filament sends its light rays in a circular path through a strip of light-conducting plastic material, such as Plexiglas, for example. The strip is positioned radially inwardly but adjacent to the tube, carrying adequate illumination to the tube contents throughout the entire tube length or circumference.
10 Claims, 3 Drawing Figures PATENTEDJUL 41972 I 3.673.697
INVENTO Z 6 2216 B. Wasszm At depths from which overhead daylight, if any, is absent or does not penetrate, in water discolored by dark colored sediment or mud agitated into dense suspension by the flippers of the diver, in caves, tunnels, and within opaque structures, such as sunken vessels, a diver may and ofien does become uncertain of his attitude or posture relative to lines of gravitational forces.
The weight and nature of his diving gear gives a diver a net buoyancy and sometimes an unfamiliar center of buoyancy different from that he would have when unencumbered by the gear. His response to gravity may be minimal and very uncer tain. At times he may unknowingly be swimming downwardly or upwardly, on his side or even on his back, especially in darkness and where he has no visible points of reference.
This invention pertains to attitude indicators, which make it possible for a diver submerged under the above described conditions to quickly ascertain, first, the angular attitude of the indicator tube itself with reference to gravitational lines of force, and then from that information to determine other additional information. One common question would be, which direction of movement would take him most quickly to the surface, should he then desire or urgently need to surface.
Hence, instant acquisition of dependable knowledge of his attitude and posture may often be needed, especially if his oxygen supply is low, lest doubt give way to panic, and panic to disaster.
One of the objects of the invention is to provide a submerged diver with an illuminated device enabling him when in darkness to ascertain without aid from other information sources, his attitude or posture with reference to lines of gravitational forces.
' Another object of the invention is toprovide a novel attitude indicator so constructed that it may be positioned encircling the forearm of a diver where it will always be visible and readily movable on the am into various registering and view- I ing positions.
Another object of the invention is to provide means onthe indicator whereby the diver may easily observe when and whether the indicator is in a vertical plane.
Other objects and advantages of the invention will be mentioned hereinafter, or will become apparent in the following description. 7
Referring now to the. drawing showing one embodiment of the invention,
. FIG. 1 is a front elevation of the indicator. FIG. 2 is a sectional view on line 22 of HO. 1;
FIG. 3 is a sectional view on line 3-3 of HO. 1.
The endless tube 11 is circular in circumference and in cross section, and while it may be made from various suitable materials, including a transparent glass, there may be used a suitable somewhat flexible plastic material, such as Tygon," easily bent to conform to the annular casing, generally indicated as 12, yet not deformable when subject to expected under water pressures when sealed and properly supported in the casing. The casing is filled with a liquid 13, except for the space occupied by bubble 14.
The casing may be made of a light weight metal or of other suitable material, and is shaped for encircling the forearm of the diver, being held thereon perpendicular to the length of the arm by any suitable means, for example spaced rubber bands 15 and 16, between which the diver may thrust hisforeann encased, usually,'in a rubber diving suit sleeve.
To provide illumination for the tube and its contents there are shown a sealable battery 17, supplying current to a lamp or bulb 18, positioned between and close to the opposite polished ends 19 and 21 of a strip of light conducting material, such as Plexiglas," or other similar acrylic having the characteristic of efficiently carrying light rays through curved and bent passages of the material.
The strip 22 is housed within an inwardly expanded annular channel 23 formed in the casing 12, holding the strip 2 against the inner surface of the tube 13.
The strip 22 and the lamp cooperate'to carry light rays in both directions from the lamp, and the light is radiated into the liquid in tube 13, making the bubble easily visible, wherever it may momentarily rest.
By bending his forearm at the elbow, the diver may view the indicator as it is viewed in FIG. 2. If the bubble be centered between the casing margins 24 and 25, which are of equal diameter, the diver knows that the plane of the tube is vertical and parallel to the lines of gravitational forces.
His palm, extended straight from the forearm rotates in unison with the forearm. Hence, his palm may be used for angle measuring by moving the palm to make it parallel with any nearby upright, or non-upright, surface, and by looking at the bubble and at degree markings on the tube, or on its casing 12, he can estimate the angular attitude of any such surface with reference to gravitational lines of force, or with reference to some other surface, and can do this in the dark. ln a similar manner, he can estimate, and remember, the angular attitude of any passagehe proposes to enter, or has just left.
It will readily be perceived that the bubble, responsive to gravity acting on the liquid in the tubeis highly mobile and instantly responsive. There will be no lag in its ability to reveal to the diver many facts he needs to learn without an instants delay. As his forearm is also highly mobile and is the carrier of the indicator, he can move his ann into many positions to quickly check on the posture or attitudeof his body, the angular inclination of his existing or proposed line of travel, and the attitude or angular positions of nearby surfaces above, below, or laterally adjacent to him, in which he may have an interest and, perhaps, a vital urgent need to ascertain such information. And with the illumination provided, he may gain the required information in total darkness.
By having a tube with a 360 arc, the bubble will never be trapped in a dead end passage, as might happen if the arc were less than 360.
lndicia markings by lines, such as zero line 27, and numerals, as desired, applied to the tubeor to the adjacent casing margins, will enable the diver to compute angles as part of the data he may be seeking.
When an uncolored gas, such as air, constitutes the bubble, it is desirable, for contrast, that the tube liquid have a preselected color different from the colors of the waters which the diver, on any venture, may expect to encounter. The contrast .in colors will make the bubble more visible, and the liquid color should not be so dark or its concentration so great as to diminish too much the lighting of the tube contents.
ln order to obtain efficient and adequate light piping in the Plexiglas light conductor 22, the radially inner surface 26, (FIG. 2) of the conductor should be coated quite heavily and uniformly with a high gloss light reflective white paint, such as a white acrylic automobile paint. This coating will reflect back into and forwardly in the conductor those light rays which strike it at various random angles, thus illuminating the entire conductor 22.
The white coat should be blanketed on its outer surface by a light impervious, opaque paint, black, for example, to prevent waste of the light.
Some of the light rays reflected off the white coating, throughout the length of the conductor, will escape through the opposite transparent polished surface of the conductor,
' which faces the tube, into the tube, thus illuminating the entire tube and its contents more than adequately, and illuminating the bubble, wherever it may be within the length of the tube.
The frame or casing 12 serves not only to support the tube but also to protect the paint coatings from water and sediment, and may be sealed in a water tight relationship with the tube.
The invention is not limited to the details of the construction herein disclosed, but includes such modifications as fall within the scope of the claims hereto appended.
Having shown and described my invention, 1 claim:
1. An attitude indicator comprising a circular annular tube containing a liquid and a bubble,
means for supporting and securing said tube in a position encircling the forearm of a diver,
and light emitting means including an arcuate light ray conductor, a battery and lamp filament means positioned to project light rays into the concluctor, said conductor being mounted parallel to the tube and being adapted to radiate light rays into the tube.
2. An attitude indicator comprising a circular annular tube containing a liquid and a bubble,
a circular annular frame proportioned for encircling the forarm of a diver and having confining surfaces adapted forsupporting the tube with substantial peripheral tube surfaces transverse the length of the tube exposed for viewing radially and laterally outside said confining surfaces,
means for securing the frame in said encircling position on the forearm of a diver,
and light emitting means including an arcuate light ray conductor, a battery and lamp filament means positioned to project light rays into the conductor, said conductor being mounted parallel to the tube and being adapted to radiate light rays into the and tube.
3. An attitude indicator in accordance with claim 1, in which the light conductor has opposite arcuate surfaces, the arcuate surface most remote from the tube having a coating of light reflective material blanketed by light impervious material thus to reflect light rays back into the conductor and to prevent leakage of light from the conductor, the arcuate surface facing the conductor being transparent and adapted to transmit light rays into the tube.
4. An attitude indicator in accordance with claim 3,
in which the arcuate surfaces of the conductor are mutually parallel.
5. An attitude indicator in accordance with claim 2,
in which the light conductor lies adjacent the inner peripheral surface of the tube and is substantially co-extensive therewith.
6. An attitude indicator in accordance with claim I,
in which the light conductor has an edge portion into which the lamp filament rays are projected.
7. An attitude indicator in accordance with claim 1,
in which the conductor has two end edge portions into both of which the lamp projects light rays, and by means of which the entire conductor is illuminated and thereby illuminates the entire tube.
8. An attitude indicator in accordance with claim 1,
in which the supporting and securing means secure the tube non-rotatably on the arm of the diver.
9. An attitude indicator in accordance with claim 1,
in which opposite lateral sides of the tube are exposed to view and lie in parallel planes whereby the position of the bubble in the tube at any moment reveals the angular. attitude of the planes of the parallel sides of the tube at such moment with reference to vertical planes lying in the gravitational lines of force.
10. An attitude indicator in accordance with claim 9,
in which circular means are provided adjoining the exposed sides of the tube for determining by reference to the position of the bubble the angular attitude of the tube with respect to gravitational lines of force.
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