Decometer

• US 4,005,282 A
• Filed: 09/25/1975
• Issued: 01/25/1977
• Est. Priority Date: 09/25/1975
• Status: Expired due to Term

• Current Assignee: the united states of america as represented by the secretary of the navy
• Original Assignee: the united states of america as represented by the secretary of the navy
• Inventors: Jennings, Kirk E.
• Primary Examiner(s): Smith, Jerry
• Application Number:
  US05/616,786
• Time in Patent Office: 488 Days
• Field of Search: 235/151.3, 235/151.32, 235/184, 73/170 R, 73/170 A, 73/432 R, 128/2 R, 128/2.1 R, 128/204, 444/1
• US Class Current: 73/865.1
• CPC Class Codes: B63C 11/32 Decompression arrangements; Exercise equipment
• CPC Class Codes: B63C 2011/021 Diving computers, i.e. portable computers specially adapted for divers, e.g. wrist worn, watertight electronic devices for detecting or calculating scuba diving parameters

Abstract

A portable decompression computer, which is capable of providing a diver'"'"'s current depth and safe-ascent depth, comprising a source of energy, for energizing various components of the computer. A micro processor is energized by the energy source. A clock generator times various components of the computer. A bus driver and status latch, timed by the clock generator and connected to the micro processor, decodes data signals received at its input and converts them to compatible voltage levels as output signals. The status latch decodes information from the micro processor and relays it to various memory input and output devices. A read-only memory (ROM), which has the main programs for the computer stored within it, can be addressed programmatically by the micro processor. A first random-access memory (RAM), connected to the micro processor, can write data into and be read by the bus driver and status latch, the memory storing the program variables. A pressure sensor and A/D converter which multiplexes depth information onto the bus driver and status latch. A second random-access memory receives information on a read-write bus regarding the current depth and safe ascent depth and stores it. A display and multiplexer has as an input the current depth and safe ascent depth, its function being to decode the address of the digit selected and determine the time on, or duty cycle, of each digit, and to display the digit.

Claims

1. A portable decompression computer, which is capable of providing a diver'"'"'s current depth and safe ascent depth, comprising:

a source of energy, for energizing and timing various components of the computer;

a micro processor, energized by the energy source, connected to an address bus, a read-write bus, a data bus in, and a second dated bus;

a clock generator for timing various components of the computer;

a bus driver and status latch, timed by the clock generator and connected by the data bus in and the second data bus to the micro processor, which decodes data signals received from the micro processor and converts them to compatible voltage levels for the second and a third data bus, the status latch decoding information from the micro processor and relaying it to various memory input and output devices;

a read-only memory (ROM), which has the main programs for the computer stored within it which can be addressed programmatically by the micro processor, and which makes its stored data available on the third data bus, connected to the bus driver and status latch;

a first random-access memory (RAM), which can be written into by the read-write bus connected to the micro processor, which can write data into and be read by the bus driver and status latch by means of the third data bus, the memory storing program variables;

a pressure sensor and A/D converter which multiplexes depth information onto the third data bus;

a second random-access memory, which receives information on the address bus from the read-write data bus regarding the current depth and safe ascent depth and stores it; and

a display and multiplexer which is energized by the source of energy, has as an input from the second random access memory the current depth and safe ascent depth, and receives timing pulses from the source of energy, the function of the display and multiplexer being to decode the address of the digit selected and determine the time on, or duty cycle, of each digit.

2. A portable decompression computer, according to claim 1 wherein the source of energy comprises:

a battery;

a timer and power control circuit, whose input is connected to the battery, which controls distribution of power to the components of the computer; and

a DC/DC converter and regulator, whose input is connected to the timer and power control, which chops the incoming voltage from the timer and power control to generate higher positive and negative voltages needed by some of the components.

3. The computer according to claim 1, further comprising:

an air-gas switch, which can be addressed by the micro processor, which determines in which mode, air or mixed gas, that the diver wants to run the computer.

4. The computer according to claim 1, further comprising:

an energy-source sensor which can be addressed by the micro processor and which can write through the third data bus into the bus driver and status latch the condition of the energy source.

5. Indicating apparatus, useful for a driver comprising:

means for sensing pressure, and therefore depth;

timing means;

means for storing safe time-depth data, to prevent the bends of a diver, at various depths for various times;

read-out means for displaying a depth; and

computer processing means connected to the pressure sensor means, timing means, storing means, and read-out means for first computing and then displaying on the read-out means a safe ascent depth;

the computer processing means comprising a micro processor, which receives the depth pressure information from the pressure sensing means, total time submerged at the various times from the timing means, and safe time-depth data from the storing means and computes therefrom the said safe-ascent depth in a manner so as to maximize the amount of time the diver can safely stay underwater.

6. The indicating apparatus according to claim 5, wherein

the pressure sensor means comprises a pressure transducer which also senses ambient depth of water;

and

the means for storing safe time-depth data comprises a read-only memory

7. The indicating apparatus according to claim 6 wherein

the computer processing means further comprises means connected to the micro processor, for controlling the flow of data to and from the micro processor, and from the read-only memory.

8. The indicating apparatus according to claim 7, wherein

the computer processing means further comprises:

a first means for storing information which can be written into and read out by the micro processor, which stores required program variables, including depth and time; and

a second means for storing information, which receives information from the micro processor regarding the current depth and safe depth, stores it, and transmits it to the read-out means for display.