US1717663A

US1717663A - Propeller

Info

Publication number: US1717663A
Application number: US238434A
Authority: US
Inventors: Checkley George
Original assignee: Individual
Current assignee: Individual
Priority date: 1927-12-07
Filing date: 1927-12-07
Publication date: 1929-06-18
Anticipated expiration: 1946-06-18

Description

June 18, 1929. G. QCHECKLEY 1,717,663

PRO/PELLER Filed Dec. 7, 1927 via; 2 l: Z :2a 7

Z/ Z5 Z4 Z4 Z4 5 INVENTOR GEORGECHEC/rZf/f Patented June 18, 1929.

UNITED STATES GEORGE CHECKLEY, OF NEW YORK, N.'Y.

PROPELLER.

Application filed December 7, 1927. Serial No. 238,434.

This invention relates to propellers and in particular to a combination of propellers so arranged that they will give the maximum etficieut operation, the same being an improvement over my Patent No. 1,607,116, granted November 16, 1926. A particular object of the invention is to provide a plurality of propellers which can be mounted upon a single shaft adjacent to each other, separated by various distances depending upon their pitch and the conditions under which they operate and the size of the propellers being so arranged that they will overcome the conditions which have heretofore been objectionable in the use of propellers.

A still further particular object of the invention is to provide a main propeller having positioned at the opposite sides thereof, auxiliary propellers which may be of various sizes and which may be preferably provided with various numbers of blades. For instance, in the present illustration of my invention the front propeller may have two blades, the main propeller three blades and the rear propeller four blades, although any number of blades may be provided on any one of the propellers to suit the conditions.

To enable others skilled in the art to fully comprehend the underlying features of my invention that they may embody the same' in the various modifications in structure and relation contemplated, a drawing depicting a preferred form has been annexed as a part of this disclosure and in such drawing, similar reference characters denote corresponding parts throughout all the views, of which,

Figure l is a view in side elevation of the end of a. propeller shaft.

Figure 2 is a view looking toward the rear of the propeller shaft showing the propellers mounted thereon and showing also how they make a solid wall whereby the water will be effectively discharged toward the rear, and

Figure 3 is a collective view of a plurality of different shaped shafts which may be employed in the mounting of the propeller whereby no loss of motion will be present and where the maximum turning effort can be employed.

Referring to the drawings in detail, 5 indicates a shaft, in this instance, of triangular formation as illustrated in Figure 2, and upon which are mounted, a plurality of propellers. These propellers are suitably spaced on the shaft and by way of illustration, 6 indicates the front propeller, 7 the main or middle propeller and 8 the rear propellers which are cast in the usual way to provide the. propeller sleeves 9 and 10 and 11 respectively. The forward propeller as lllustratedis provided with two

blades

12 and 13, which are identical in size and are of greater width adjacent their outer extremities, the blades themselves being relatively smaller than the blades of the main propeller 7 whose blades 14 are likewise widened at their uppermost portions and are cast integral as before stated, with the sleeve 10. In this instance there is provided three blades 14 which are equally spaced about the periphery of the sleeve 10 in spaced relation with the main or center propeller 7, the propeller 8, which consists of four blades 15, which are also widened at their outer ends to give the maximum driving power, are of a diameter not to exceed 45% of the main propeller blades.

In this connection, it is to be understood that either the front or the rear propeller or bdth may be of like size or may be of varying sizes but in no instance is either propeller to exceed 45% -of the diameter of the main propeller. This I have worked out as beingnearly the right proportion to obtain the maximum driving power from all three of the propellers when used in combination.

It is a well known fact that the operation of the shaft and the operation of the main propellers set up a partial vacuum around the shaft adjacent the base of the propeller blade and consequently a loss of driving power is the result.

In order to overcome this objection, I have made use of a relatively small front propeller, as illustrated, which will break up the body of the water and which will direct it toward the center of the main propeller and the main propeller in turn will churn the water up and drive it rearwardly at which point the rear propeller will act upon it with all four blades to obtain from the water the maximum pushing power.

It will be quite evident that the blades may or may not be in alignment, in view of the fact that their relative diametric relation will effectively perform the work in an etlicient manner.

In order to hold the propellers on the shaft 5, I have provided end collars 16 and 17 which are secured in position through the medium of the usual set screws 18. In order to separate the propellers any desired distance, use is made of the

spacing collars

19 and 20, the latter of which, as illustrated, is longer than the collar 19 and thus the propellers may be spaced any desired distance depending upon the results obtained as the result of experimentation.

In order that the maximum operation may be had, use may be made of tvarious shaped propeller bores and various shaped shafts upon which the same may be mounted, and it will be noted in Figure 3, that a square shaft 21 may be employed, a fluted shaft being illustrated at 22, while at 23, there is shown a substantially diamond shaped shaft.

The other forms of the shaft indicated by the numeral 24 may be of any polygonal shape and number 25 indicates a shaft, the sides of which have been flattened as at 27 to receive the collars and sleeves of the propellers. Numeral 28 indicates a shaft, the diametrically opposite sides of which have been rooved as at 29 to provide a means Vll7l1efIt8T)y the propellers may be secured to the s 121 v It is to be understood that in all of the forms of the shaft shown in Figure 3, a matching bore will be provided in the propeller sleeve and in the collar separating the .same in order that the maximum driving power may take place and slipping between the shaft and the propeller will thus be eliminated.

The propellers may be made of light construction and need not exceed the weight of the usual single propeller, because the great driving load is distributed between the three propellers and consequently, they need not be of as heavy construction.

It is evident, therefore, that in a propeller arrangement of this type, the greatest driving force will be obtainable and consequently the greatest efiiciency arrived at due to the fact that suctions will not be created at the base of the propeller blades and a greater driving surface will be provided.

It is evident also that variations in the sizes of the blades may be made up to the limit noted and the blades may be spaced any particular distance apart desired.

It is also evident that in conjunction with a main propeller, two auxiliary propellers on the front and rear thereof may be provided for obtaining the maximum driving power.

While I have illustrated and described my invention with some degree of particularity,

a rear auxiliary propeller, the front propeller having a lesser number of blades than said rear propeller and a main propeller disposed between said auxiliary propellers.

2. The combination with a propeller shaft of a plurality of propellers mounted thereon and comprising a front auxiliary propeller, a rear auxiliary propeller, the front propeller having a lesser numbero-f blades and being of a lesser diameter than said rear propeller and a main propeller disposed between said auxiliary propellers.

3. The combination with a propeller shaft of a plurality of propellers mounted thereon and comprising a front auxiliary propeller, a rear auxiliary propeller, the front propeller having a lesser number of blades than said rear propeller and one of said auxiliary propellers being of lesser diameter than the other and a main propeller disposed between said auxiliary propellers. 4. The combination with a propeller shaft of a plurality of propellers mounted thereon and comprising a front auxiliary propeller, a rear auxiliary propeller, the front ropeller having a lesser number of blades t an said rear propeller and being of lesser diameter than said rear propeller, a main propeller. disposed between said auxiliary propellers and separating collars of different lengths between said propellers.

5. The combination with a propeller shaft of a plurality of propellers mounted thereon and comprising a front propeller having two blades, a rear auxiliary propeller having four blades and a main propeller disposed between said auxiliary propellers and being provided with three blades.

In testimony whereof I affix my signature.

GEORGE CHECKLEY. 1. 3.

I therefore reserve