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Publication numberUS1314718 A
Publication typeGrant
Publication dateSep 2, 1919
Filing dateDec 18, 1916
Publication numberUS 1314718 A, US 1314718A, US-A-1314718, US1314718 A, US1314718A
InventorsNikola Tesla
Original AssigneeWaltham Watch Company
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Nikola tesla
US 1314718 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)


SHIPS LOG. Armenio meu orma. 1915.

1 ,3141,71 8. `Patvnted Sept. 2, 1919.


. A 2 Y 51, eww albumi UNITED sTATEs PATENT oEEICE.



Specification of Letters Patent.

Patented sept. 2, 1919.

yAppiiaanm mea December 1s, 191e. seria; No. 137,690. l

' To all 'whom z't may concern:

' provementsy in Ships Logs, of which the following is a full, olear, and exact description.

My invention provides a ships log of novel and advantageous construction p andv operation, deslgned to give instantaneous rate-readings, as in knots, or miles per hour. The customary log is trailed "astern, twisting the Hexible connector that drives ayrevolution-counter on the vessel, and many disadvantages of such arrangement are obvlous.

In my lnstrument I comblne very advantageously a propeller rotatable proportionlately to vessel-speed and a speed indicator driven by it and reading directly in 'the desired terms, preferably upon a substantially uniformly-graduated scale. l

In the drawings, Figure 1 diagrams the log in use;

Fig. 2 shows it in vertical section; Fig. 3 illustrates speed-indicator parts with the casing broken away;

Fig. 4 is a section on line 4-4of Fig. 3; Fig. 5 is asection on line 5-5 of Fig. 2. Fig.' 6 shows in section a turbine form 'of propeller, and 'A Fig. 7 is a section on line 7 -7 of Fig. 6. To the vessel 10, preferably near its bow,

lis suitably affixed a tube or barrel, 11, with indicator and a seal 19 for its fiexible drive- 'i shaft 20 that connects'pre'ferably throu h a slip-'joint squared union, 21, to a prope lerdriven part. The propeller may be of com` mon form as shown in Fig. 2, at 22, with its shaft 23 horizontally mounted in the bracket 24 spanning the tubular passage -25 of a housmg 26 that fits neatly in lthe barrel and is'held in register with' ports 27 and 28 by guide-ribs 29. Such a propeller drives the shaft v20 through bevel gears 30.

More advantageously in some respects, however, a .turbine propeller of simple construction inay be employed, as shown in Figs. 6 and 7. The rotorin this instance i has a vertical shaft 23 and the wheel 22 is formed of thin, parallel, closely-spaced disks each having a centrall opening.y The wheel is arranged in af cylindrical housing 26 that has inlet nozzles 31 and outlet ports 32 so disposed that the water enters the interspaces between the disks tangentially to rotate the wheel and finds escape through the ports 32 that communicate with the eentral oriices of the disks. This type of construction has many advantages due to its reliability and eiciency, but preferably it should be constructedto permit the disks and casin to be readily cleaned, Vcasing 26 being ma ein two horizontal sections bolted together as at 33, each section having a detachablel head- 34.

A fiexible and longitudinally elastic sleeve, 35, of coiled strip metal is fastened at opposite ends by threaded caps 36 and 37 to the boss 17 and to a threaded part on the propeller` casing, so that the ropeller mechanism is supported from the indicator corrosion, adequatev durability is attained,

and the facility of removal for cleaning, oiling, repairs, etc., .makes the under-water parts easy to maintain in ood order. The

pliant shaft7 slip-connecte at one end and its stout protective sleeve, strong yet fiexible and extensible frees the bearings from strain and makes the connection uniformly etlicient under changes of conditions asI to temperature, etc.

The speed indicator 13 preferably provides as its primary element 41 a multiplewalled cup,y fast on shaft 20, and as a secondary, or indication-giving, member a lightly-constructed pivoted, multiple-walled inverted cup structure 42, with the annular walls interleaved in closely adjacent noncontactng relation for transmission of turning effort from the on'e to the other through intervening films of the casing-containedluid medium, as air, in approximately linear Isiroportion to the speed of the primary.

pecifically the` secondary cups arey dependent from an arm 43 projecting from spindle 44, having jewel 'bearings in yoke ,45 carried by bridge-piece, 46, that spans nected at its ends respectively to the pivoted secondary element and to a fixed support, resists the pivotal displacement of the indicaton-giving member. The light secondary element, quickly and accurately responsive approximately directly proportionately to the speed of the propeller-driven primary member, and little affected by tremors, temperatu're changes and other extraneous inuences,A gives adequately accurate readings in the desired terms, showing instantaneously changes of the vessels speed.

1. In ships log, a barrel having Water flow openings near its bottom, a speed-in` dicator detachably secured to one end of the .-barrel, a flexible shaft for the speed-indicator, a propeller connected tothe shaftend, a housing for the propeller, registering With' the water-flow openings, and a sleeve surrounding the shaft uniting the housing and casing, `for extraction of the propellerparts when the speed-indicator is 'removed from the barrel.

42. In a ships log, abarrel, a speed indicator having a casing secured detachably to the upper or'observ'ation end ofthe barrel,

bottom, a speed indicator having a casing detachably secured to one end of the barrel, a shaft for said speed indicator extending centrally through the barrel, a propeller for the shaft end, a housinfr for the propeller, said housing being smal er than the barrel, and a sleeve surrounding the shaft uniting said housing and said indicator casing for effecting extraction of the propeller parts when -the speed indicator is removed from the barrel.

4. In a ships log, a barrel, a speed indicator having a casing secured detachably to the upper en d -of the barrel, a propeller h aving a housing and adapted to pass through the barrel, there being registering open- ,ings nearthe bottom of the barrel and in said housing for Water-flow to the propeller, a flexible shaft connecting said propeller and speed indicator and making axially slidable connection with one thereof, and a vflexible and axially expansible sleeve connecting the )ropeller housin and the indicator casing lor extraction o the propeller parts when the speed indicator is removed from the barrel.

In'testimony whereof I affix my signature.


Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2773383 *Feb 11, 1955Dec 11, 1956Kersten Herbert HSpeedometer and odometer for boats
US3003354 *Jun 26, 1959Oct 10, 1961Electro VoiceFluid flow measuring device
U.S. Classification73/187
Cooperative ClassificationG01P5/07