Navigation drawing and calculating disk

Abstract

The invention relates to a navigation painted abacus, which comprises panels 1, a movable rotary disk 2, a logarithmic calculating disk 3, a movable scale 4 and a logarithmic ratio scale 5, wherein, the panels 1 are divided into an upper layer and a lower layer; the movable rotary disk 2 is a circular disk and fixed between the upper and lower panels 1, and can freely rotate around the center of the circle; the movable rotary disk 2 is engraved with two main index lines 6 which pass through the center of the circle and are perpendicular to each other, and a plurality of auxiliary index lines 7 parallel to the main index lines 6; the disk surface is engraved with a distance / speed circle 8 used for measuring the distance / speed, and the outer ring of the rotary disk is engraved with an azimuth scale line 9 of 0 to 360 degrees. The upper and the lower panels 1 are made of organic glass, lined by copper strips, and fixed by screws; and each corner is subjected to slow round processing. The logarithmic calculating disk 3 consists of an inner disk 10 and an outer disk 11 which have the same circle center, wherein, the inner disk 10 can freely rotate, and the outer disk 11 is a fixing disk. The movable scale 4 is made of copper materials, concentric with the movable rotary disk 2 and fixed on the upper panel 1 by the inside thread screws, and can freely carry out circumferential rotation. The logarithmic ratio scale 5 is a strip-shaped plexiglass ruler, one side of which is engraved with logarithmic scale, and can be used as a logarithmic slide rule by matching with the movable scale (4) on the movable rotary disk (2).

Description

Technical field [0001] The invention relates to a nautical drawing abacus, which is a practical reform of the active nautical drawing calculation tools. In terms of practicability, it is characterized by convenient use, easy to carry, fast drawing and calculation, intuitive image, and economical and applicable. Background technique [0002] When navigating at sea, ships must carry out chart operations to ensure the safety of ship navigation. To draw a route on a chart, it is necessary to use a navigation drawing tool to measure the course or other degrees related to the course on the chart. The drawing tool commonly used in the nautical field at present is the nautical set square, which includes two identical set squares, and each set of set squares is marked with a scale of 0°~180° and an inverted 180°~360°, and Each degree has a scale line opposite to it, the intersection point of the scale lines is the center point, the long side of the triangular plate is the bottom sid...

AI Technical Summary

Problems solved by technology

However, this method is inconvenient and inaccurate

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