US1550955A - Counterbalance for rudders - Google Patents

Description

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Aug. 25; 1925. q

' A. FLETTNER COUNTERBALANCE FOR RUDDERS Filed Jan. 25, 1923 \J in, Na.

ANTON FLETTNER, 0']? BERLIN-SCHONEBERG, GERMANY.

COUNTERBALANCE FOR RUDDERS.

Application filed January 25, 1923.

To all whom it may concern:

Be it known that I, AN'roN FLETTNER, a citizen of Germany, residing at Berlin- Schoneberg, Germany, have invented certain new and useful Improvements in Counterbalances for Rudders, of which the following is a specification.

My invention refers to rudders for the steering of water craft and its particular object is to counterbalance the weight of the rudder. It has already been tried to diminish the force required for adjusting the rudder by equalizing the forces exerted upon the rudder by the flow, that is to say, by enlarging the rudder surface beyond the rudder pin in the direction towards the bow of the vessel, or by arranging special auxiliary surfaces on lever arms, the arrangement in each case being such that the turning moments exerted by the current pressure upon the rudder surface in front and to the rear of the rudder spindle are balanced relatively to this spindle. This is the case if the centre of pressure of the entire rudder surface system coincides with the rudder axis.

Investigations have shown that there arise further unequalized forces especially with large rudders the surfaces of which are not disposed symmetrically with respect to the axis and whose centre of the masses does not coincide with the rudder pin. There then arise around the rudder pin, es pecially if the vessel is in an oblique position, forces due to weight or gravity which must be overcome by the rudder driving gear. In the case of large sized rudders, these additional driving forces are considerable, but as in cases of this kind steering engines or. self-locking drives are provided, they do not play an important role, because these driving means are uneconomical per so. However, in the case where the rudder shall be adjusted by small forces for instance with the aid of an auxiliary rudder, these additional forces must be taken into consideration.

These additional forces are obviated, according to the present invention, by wholly or partly counterbalancing the weights of the rudder system relatively to the rudder spindle.

This may be effected in various manners. In the drawings ailixed to this specification and forming part thereof several devices embodying my invention are illus- Serial No. 614,916.

trated diagrammatically by way of example. In the drawings- Figure 1 is a side-elevation, partly in vertical section, and

Figure 2 is a plan of one modification, while Figure 3 is an elevation of a second modification.

Referring to the drawings, a is the stern of the vessel, 6 is the rudder which is adjusted with the aid of an auxiliary rudder 0. The main rudder b is partly balanced in that the rudder surface is extended beyond the rudder spindle d in the direction towards the bow. The equalization of weights of the rudder system relatively to the rudder axis is effected by providing preferably within the hull of the vessel a counterweight o, for instance of lead, which is secured either directly on the spindle d or on an arm afiixed thereto and the weight of which is so determined that the centre of gravity of the entire system coincides with the rudder axis. The equalizing mass need not be arranged within the hull, but may be located for instance, if desired, in the rudder body which may be at least partly hollow for the reception of the mass in question.

The weights may be balanced also by auxiliary surfaces which are so arranged that the current pressure acting thereon effects the equalization. These auxiliary surfaces may, if desired, also serve for balancing the weights. This balancing may, however, be effected also by the provision of a hollow space, such as 7 (Figure 3) in the rudder body which increases the buoyancy of the rudder.

The drawing shows the novel arrangement applied to a vertical rudder, but it may be used also in connection with other rudders, especially horizontal rudders for altitude steering in submarines and the like.

I wish it to be understood that I do not desire to be limited to the exact details of construction shown and described, for obvious modifications will occur to a person skilled in the art. a

I claim 1. Steering means for watercraft comprising a vertical spindle, a rudder disposed asymmetrically on said spindle and means separated from the rudder surface for substantially balancing the weight of said rudder acting on said spindle.

2. Steering means for Watercraft comdisposed asymmetrically on said spindle, an prising a vertical spindle, a rudder disauxiliary rudder connected with said main 10 posed asymmetrically on said spindle and a rudder and means separated from the rudcounterweight separated from the rudder der surface for substantially balancing the 5 surface for substantially balancing the Weight of said rudder acting on said spindle.

Weight of said rudder acting on said spindle. In testimony whereof I afiiX my signa- 3. Steering means for Watercraft comture.

prising a vertical spindle, a main rudder ANTON FLETTNER.

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