A circular slide rule for use by scuba divers which coordinates the variables of air tank pressure, depth of submergence, breathing rate, and time and with which a variable may be determined when the others are known. The time available at depth is disposed on a scale formed as two separate parts, the first being from surface to an intermediate depth and the other from the intermediate depth to maximum depth which provides greater accuracy at greater depths, where it is most needed. The discs of the slide rule are flexible and of various diameters permitting the selective locking together of different combinations of same by the fingers of the user.
A new device including a new arrangement of dive tables is disclosed for planning non-decompression dives. The invention utilizes two separate scales, movable relative to one another. The first scale shows the pressure group scale, the bottom time or residual nitrogen scale and surface intervals aligned by relationship to pressure group. The second scale shows depth scales, repetitive dive group, pressure group, and no decompression time limits scale. Windows in the second scale allow the observation of pressure group scales and corresponding bottom time on alignment of bottom time from scale one with depth from the second scale.
An apparatus used to correlate and selectively read information from tables dealing with the extent of nitrogen absorption in a scuba diver's body. Tables containing information relating to the amount of time a diver spends at various depths, decompression procedures, the surface interval between repetitive dives, and the resultant amount of nitrogen accumulation in the diver's body are attached to an inner tube. Two side-by-side outer tubes, each having sight windows for selective reading of the tables, are arranged concentrically about the inner tube, and are secured in lateral position by end caps attached to the inner tube. Each outer tube is provided with inwardly projecting flanges on each end which serve as bearing surfaces for rotation about the inner tube. The apparatus is preferably slipped over a scuba tank air hose for carrying.
The invention concerns a decompression air supply indicator for divers which was created by expanding the function of the existing mechanical decompression meter by the inclusion of an additional scale which indicates both the time indication of the length of the decompression and the air supply necessary for the decompression.
A decompression meter includes a scale having a first section corresponding to conditions in which it is unnecessary for an ascending diver to carry out decompression halts, and a second section corresponding to conditions in which decompression halts are necessary. The second section of the scale is carried by a movable element which can be displaced along the first scale section by means of a manually operable member. Means are provided for indicating the position of the movable element along the first scale section. The position in which the movable element is set is selected by the diver at least on the basis of the maximum depth reached and, optionally, also on the basis of the dwell time at this maximum depth as well as possibly also on the basis of the intervening time between a preceding dive and the current dive.
There is disclosed a garment wear monitor for recording the number of times an article of clothing is worn. The monitor is removably or permanently affixed to a clothing hanger, or is removably affixed to the garment directly. Each time the garment is worn the garment wear monitor is advanced by one number manually or automatically. The garment wear monitor may also display the date on which the garment was last cleaned. A threshold indicator serves to remind the user to have the garment cleaned when a predetermined number of wearings have taken place. The garment wear monitor may display the number of wearings and the date of last cleaning by a mechanically movable scale or by an electronic digital display.
