US3690787A

US3690787A - Apparatus for indicating the position of the control center for the blades of a rotating blade propeller

Info

Publication number: US3690787A
Application number: US141205A
Authority: US
Inventors: Harald Gross
Original assignee: JM Voith GmbH
Current assignee: JM Voith GmbH
Priority date: 1970-05-16
Filing date: 1971-05-07
Publication date: 1972-09-12
Anticipated expiration: 1989-09-12
Also published as: GB1343926A; DE2024146A1; DE2024146B2; JPS5014795B1; FR2091211A5

Abstract

A blade wheel ship propeller has a rotatable hub from which a plurality of blades extend vertically downwardly adjacent the periphery thereof with the blades being pivotable about their longitudinal axes. The blades are connected to a displaceable control disk in the hub which determines the center of eccentricity for the blades. A vertically extending universally tiltable control member has one end pivotably connected to the control disk and its upper end pivotally connected to the lower end of a measuring rod which is gimbal mounted or firmly connected in a propeller housing. The angles of tilt of the gimbal mounting axes or the magnitude and direction of bending of the measuring rod are sensed and transmitted to remotely located indicators to indicate the position of the control center with respect to a reference point on the propeller.

Description

United States Patent Gross [54] APPARATUS FOR INDICATING THE POSITION OF THE CONTROL CENTER FOR THE BLADES OF A ROTATING BLADE PROPELLER [72] Inventor: Harald Gross, Sohnstetten, Germany [73] Assignee: J. M. Voith GmbH,

Heidenheim/Brenz, Germany [22] Filed: May 7,1971

21 Appl. No.: 141,205

[30] Foreign Application Priority Data May 16, 1970 Germany ..P 2024 146.7

52 us. (:1. ..416/61, 416/108, 416/111 51 Int. Cl. ..B63h 1/10 58 Field of Search ..416/61,l08, 110,111

[56] References Cited UNITED STATES PATENTS 2,015,514 9/1935 Ehrhart ..416/108 2,978,036 4/1961 Schneider ..416/108 51 Sept. 12, 1972 6/1961 Hub ..4l6/l08X 3/1966 Baer ..4l6/l08 UX [5 7] ABSTRACT A blade wheel ship propeller has a rotatable hub from which a plurality of blades extend vertically downwardly adjacent the periphery thereof with the blades being pivotable about their longitudinal axes. The blades are connected to a displaceable control disk in the hub which determines the center of eccentricity for the blades. A vertically extending universally tiltable control member has one end pivotably connected to the control disk and its upper end pivotally connected to the lower end of a measuring rod which is gimbal mounted or firmly connected in a propeller housing. The angles of tilt of the gimbal mounting axes or the magnitude and direction of bending of the measuring rod are sensed and transmitted to remotely located indicators to indicate the position of the control center with respect to a reference point on the propeller.

6 Claims, 3 Drawing Figures THE CONTROL CENTER FOR THE BLADES OF A ROTATING BLADE PROPELLER The present invention relates to, rotating blade propellers for ships, more particularly, to the indication at a remotely located point of the position of the control center of the rods for pivoting the blades.

Blade wheel or cycloidal propellers of the type known as the Voith-Schneider propeller comprise a disk shaped rotor body or hub pivotably mounted in a propeller housing which is firmly attached to the body of a ship. A plurality of blades are mounted on the hub adjacent its circumference and project vertically downwardly from the hub. These blades are pivotable about their longitudinal axes so as to feather or oscillate about these axes. The blades are each connected by driving rods to a control plate whose center is eccentrically positioned with respect to the rotary axis of the propeller so that with each rotation of the propeller hub the blades are oscillated about their respective longitudinal axes. The magnitude of the oscillation is determined by the distance between the control center and the axis of rotation of the propeller hub. The control plate comprises a control disk which is displaceably mounted on the bottom of the propeller hub in the interior thereof with a plurality of actuation rods pivotally connected to the circumference of the control disk and to corresponding blades. The similar oscillating movements of the blades produce a directed stream of water or thrust in a direction which is substantially perpendicular to a plane passing through the axis or rotation of the propeller and the center of eccentricity.

A control member in the form of a column or stick is pivotably mounted in its central portion in the propeller housing so as to be tiltable in all directions andis coaxial to the axis of rotation of the propeller hub when in its vertical rest position. The lower end of the control member is pivotally connected to the control disk and the upper end is pivotally connected to a pair of servo-motors positioned on the propeller housing at right angles to each other.

The shifting in position of the upper end of the control member under the action of the servo-motors is directly transmitted to the lower end of the control member which in turn correspondingly positions the control disk. The shift in position of the control disk with respect to a fixed point on the propeller housing can be indicated precisely by mounting a position indicator on the upper end of the control member. It has also been proposed to transmit the position of setting of each servo-motor operatively connected to the upper end of the control member by means of a potentiometer whose axis is connected mechanically to a displaceable component of the servo-motor. The transmission of these positions to a remotely located point.

does not correspond accurately to the actual position of the control disk. Known systems for indicating at a remote position the setting of such a blade wheel propeller are not generally satisfactory since they do not transmit the correct propeller setting. The position of the control disk can be quickly adjusted from the bridge of the ship by a simple control system which is known in the art. The thrust from such a propeller can act in any direction. Since the position of the control disk and hence the direction of thrust can be quickly changed it is necessary that the real angle of the position of the control disk be known at all times on the bridge in order that the movements of the ship can be accurately controlled and overload of the prime movers avoided.

It is therefore the principal object of the present invention to provide a novel and improved device for indicating accurately at a remotely located place the setting of a blade wheel or cyclodial propeller.

Another object of the present invention is to provide such a device which can be constructed as a structural unit so as to be completely independent of the type and size of the blade wheel propeller and which can be positioned on the upper portion of the propeller housing separately from the interior of the blade wheel propeller.

A further object of the present invention is to provide a simple and relatively inexpensive but a highly accurate and reliable device for accurately sensing and transmitting to a remotely located place the setting of a blade wheel propeller.

The objects of the present invention are achieved and the disadvantages of the prior art are eliminated by the present invention in which there is essentially pro vided an apparatus for indicating the position of the center of eccentricity of the blade actuating mechanism of a blade wheel or cycloidal propeller. Such a propeller comprises a disk shaped rotor body or hub rotatably mounted in a propeller housing with there being a plurality of downwardly extending blades positioned adjacent the circumference of the body. The blades are pivotable about their longitudinal axes and are connected by a plurality of rods to a control disk or plate for feathering or oscillating the blades during each revolution of the propeller hub. The direction of thrust delivered by the propeller is perpendicular to a plane passing through the center of eccentricity and the rotary axis of the propeller hub. A control column is mounted at its central portion for universal tilting movement and has its lower end pivotally connected to the control disk defining the center of eccentricity. A pair of servo-motors mounted on the propeller housing at right angles to each other are pivotally connected to the upper end of the control column. A measuring rod has its lower end pivotally connected to the upper end of the control column and is fastened to the propeller housing at a point spaced from its lower end. Means are provided responsive to the movement of the measuring rod as it moves to response to the control column for indicating variations in the position of the measuring rod with respect to a reference point on the propeller housing. The indicating means may comprise a pair of potentiometers mounted at right angles to each other with one potentiometer being connected to measure tilting of the measuring rod and the other potentiometer connected to indicate tilting of the frame to which the measuring rod is gimbally connected.

The measuring rod may be firmly secured to the propeller housing and foil strain gages means mounted on several measuring points on the measuring rod for indicating variations of the strains exercised on the measuring points of said measuring rod in response to the movement of the control column.

With the arrangements of the indicating means as described abovean accurateiindication of the position of the center of eccentricity of the blade actuating mechanism can be transmitted to a remotely located point such as a control bridge of a ship so that the exact angular position of the center of eccentricity is precisely known at all times.

Since the central portion of the control column and the mounting point of the measuring rod have a considerable distance, the distance between the connection point of the measuring rod to the control column and the mounting point of the measuring rod to the propeller housing varies accordingly. The measuring rod may be provided with a telescoping connection between two portions thereof so that the length of the measuring rod varies to conform to the distance between the connection and mounting points on the measuring rod.

Other objects and advantages of the present invention will be apparent upon reference to the accompanying description when taken in conjunction with the following drawings, which are exemplary, wherein;

FIG. 1 is an elevational view of a schematic representation of a blade wheel propeller in which the present invention is incorporated;

FIG. 2 is a perspective view of a gimbal mounted measuring rod according to the present invention in a scale enlarged over that of FIG. 1; and

FIG. 3 is a perspective view of a measuring rod which according to the present invention is bendable.

Proceeding next to the drawings wherein like reference symbols indicate the same parts throughout the various views a specific embodiment of the invention will be described in detail.

In FIG. 1 there is illustrated a blade wheel or cycloidal propeller of the Voith-Schneider type which comprises a propeller housing 2 firmly mounted on the hull l of a ship. Such a propeller is generally mounted in the after part of the ships bottom. The propeller comprises a disk shaped rotor body or hub 3 having a plurality of blades 4 extending vertically downwardly therefrom and positioned adjacent the periphery of the hub 3. The blades are pivotably mounted so as to feather or oscillate about their own longitudinal axes. The hub 3 is drivingly connected by bevel gearing 6 to a driving motor which is similarly fixedly mounted in the hull of the ship.

Within the propeller housing 2 there is provided a bearing journal 8 in which is mounted a bearing bush 9 to receive a spherical head on the central portion of a control column 10. The control column or stick is thus mounted for universal tilting since it is capable of tilting in all directions about its spherical head on its central portion. When the control column is in its normal or rest position, it will be vertical and coaxial to the axis of rotation of the propeller hub 3.

In a similar manner the lower end' of the control column 10 is provided with a ball joint connection to a control plate 11A or control disk which is displaceably mounted within the propeller hub 3 at the bottom thereof. A blade-driving or oscillating rod system is indicated at 7 for one of the blades and is connected to the control plate 11A within the propeller hub 3.

The upper end 11 of the control column 10 which is also in the form of a ball joint is pivotally connected to the movable components of servo-motors l2 and 13 which are mounted at right angles to each other on the propeller housing 2.

At the upper end 11 of the control column there is also provided a ball joint connection to the lower spherical end of a measuring rod 14 which is moved without play in a spherical socket which is coaxial to the longitudinal axis of the control column 10. In its normal or rest position, the measuring rod 14 is also vertical and coaxial to the axis of rotation of the propeller hub 3. The measuring rod 14 is mounted at a point spaced from its lower end and generally near its upper end to a gimbal mounting 16 in a frame 15 secured in the upper portion of the propeller housing 2 so that the measuring rod is tiltable in all directions.

The gimbal mounting 16 illustrated in FIG. 2 shows the measuring rod 14 with a spherical lower end 17 for the purpose of a ball joint connection to the upper end of the control column which is not shown in this figure. The measuring rod 14 comprises a lower cylindrical portion 14 A having a small diameter and an upper portion 14 B whose lower portion is provided with a cylindrical socket or sleeve 14 C into which the upper end of portion 14 A is slideably mounted so as to be axially displaceable therein. The length of the measuring rod portion 14 A which is slideably received in the socket 14 C is several times greater than the diameter of lower portion 14 A.

The upper end of the measuring rod 14 is pivotably connected by a shaft or pin 18 in a circular frame 19 with the shaft 18 being perpendicular to the longitudinal axis of rod 14. The circular frame 19 is pivotably mounted in the stationary frame 15 by means of pins 20 and 20 A located in the same transverse plane with respect to the measuring rod 14 as shaft 18 but having the longitudinal axes thereof perpendicular to the shaft 18. The pins 20, 20 A attached to the frame 19 project outwardly of the outer periphery of the frame thereof. The frame 15 which may also comprise a closed housing is rigidly secured to the propeller housing 2 so as to be stationary. A potentiometer 21 is non-rotatably mounted on an end of the shaft 18 and a second potentiometer 23 non-rotatably mounted on the pin 20 of the gimbal mounting 16. The housing of potentiometer 21 is mounted on the circular frame 19 and the housing of potentiometer 23 mounted on the stationary frame 15. The angle of tilt of the shaft 18 with respect to the annular frame 19 is thus measured by the potentiometer 21 and the angle of tilt of pin 20 with respect to the annular frame 19 is thus measured by the potentiometer 21 and the angle of tilt of pin 20 with respect to the stationary frame 15 is measured by potentiometer 23. The values measured or sensed by the potentiometers are transmitted to suitable indicators which may be located at remote points in a manner which is known in the art and is not illustrated in the drawings.

As the position of the center of eccentricity or center of the control disk 11 A is varied from the bridge by a normal control system the lower end of control column 10 will move the control disk 11 A. The displacement of the upper end of control column 10 will pivot the measuring rod 14 because of the ball joint connection 17 between the measuring rod and control column 10. Pivoting or tilting of measuring rod 14 along axis U-U will be measured by potentiometer 21 which is rigidly connected to the shaft 18 secured to measuring rod 14. Tilting of the measuring rod 14 in the other direction along axis T-T will cause a pivoting of the frame 19 about the pins 20, 20 A and this pivoting will be

meathe potentiometers

21, 23 are parallel to the axes of the servo-motors '11, 12 of FIG. 1 indicated by the dot-dash lines passing through the ball connection 17 on the lower end of measuring rod 14 in FIG. 2. The angles of tilting of the measuring rod 14 are thus accurately sensed by the

potentiometers

21, 23 and these values are accurately transmitted to suitable indicator devices known in the art.

' In FIG. 3 there is illustrated a modified measuring rod which is mounted so as to be bendable in response to movements of the control column 10. The measuring rod is generally indicated at 24 and has its upper end secured in a frame or housing 25 located above or in the upper portion of the propeller housing and not shown in the drawings. The measuring rod 24 comprises an upper cylindrical shaft 24 A having a flexural member 24 C in its central portion of smaller diameter and a lower cylindrical portion 24 B which is widened at its upper end to form a cylindrical sleeve 24 D that slideably receives the lower end of shaft 24 A so that the shaft 24 A is axially displaceable therein without play. As a further modification the flexural member 24 C may be replaced by a flexible corrugated tubular portion which is also positioned between the portion of shaft 24 A which is fixed in the housing and that portion of shaft 24 A which is inserted in the sleeve 24 D. The length of the portion of the shaft 24 A inserted in the sleeve 24 D is at least three times the diameter of the shaft 24 A.

Because of the two-part construction of measuring rod 24 and its telescopic connection between its two components the length of the measuring rod 24 is variable and is adjusted automatically in response to the variation in the distance between the lower spherical end of measuring rod 24 pivotally connected to the upper end of the control column and its point of attachment in frame 25. This variation in distance is caused by the movement of the upper end of the control column in response to positioning of the control plate 11 A.

A pair of

foil strain gages

26, 27 and 28, 29 are mounted on the fixed circular cylindrical shaft 24 A below its point of attachment to frame 25. The strain gages are positioned along two mutually perpendicular straight lines X, Y which correspond with the directions of displacement of the servo-motors. The strain gages are disposed in a plane perpendicular to the longitudinal axis of the measuring rod 24 in such a manner that the measuring ranges of the gages are parallel to the longitudinal axis of measuring rod 24. The values measured by the strain gages in response to the bending of the measuring rod 24 as the upper end of control column 10 is moved are transmitted to indicators positioned at remotely located points by systems known in the art and not illustrated in the drawings.

The foil strain gages thus detect the variation in position of measuring points with respect to a reference point on the measuring rod in response to tilting of the control column in response to displacement of the control plate 11 A. The shifting of the upper end of the control column which occurs on actuation of the servomotors will produce a bending in the measuring rod which is detected by a strain gage strip or strips dependent upon the bending of the measuring rod with respect to the perpendicular axes of the servo-motors 11, l2-of FIG. 1 as indicated by the dot-dash lines V, W passing through the ball connection 17 in the lower end of measuring rod 24 of FIG. 3.

The modified measuring rod arrangement illustrated in FIG. 3 having its upper end fixedly mounted in a stationary frame is simpler in construction and hence less costly.

Thus it can be seen that the present invention has disclosed several embodiments for indicating at remote points the position of the control center of the actuating mechanism of a blade wheel propeller. The setting of the control center must be precisely indicated since the direction of thrust produced by the propeller is dependent upon the position of the control center with respect to the rotary axis of the propeller hub. The present invention provides an apparatus for accurately transmitting values which are directly responsive to the setting of the control center in a simplified and low cost manner in accordance with the high standards required for the accurate control of ships. The embodiments described herein can be constructed in a frame housing for various sizes of propellers and may be positioned above on the propeller housing.

It is understood that this invention is susceptible to modification in order to adapt it to different usages and conditions and, accordingly, it is desired to comprehend such modifications within the invention as may fall within the scope of the appended claims.

What is claimed is:

1. In an apparatus for indicating the position of means defining a center of eccentricity of a blade of a actuating mechanism blade wheel propeller in which the direction of thrust is perpendicular to a plane passing through the center of eccentricity and the rotary axis of the propeller, said propeller comprising a control member mounted at its central portion for universal tilting movement and having a lower end pivotally connected to the center means and an upper end, a pair of servo-motors mounted on the propeller housing at right angles to each other and pivotally connected to the upper end of said control member, a measuring rod having a lower endpivotally connected to the upper end of said control member and fastened to the propeller housing at a point spaced from its lower end, and means responsive to the movement of said measuring rod as it moves in response to said control member for accurately indicating variations in the position of said center means with respect to the rotary axis of the propeller.

2. In an apparatus as claimed in claim 1 and comprising means including a frame firmly connected to the propeller housing for gimbal mounting said measuring rod at said point spaced from its lower end, potentiometer means, said gimbal means comprising pin means non-rotatably connecting said measuring rod and said frame to said potentiometer means whereby the angles of twist of the respective pin means are sensed to indicate the position of said centermeans.

3. In an apparatus as claimed in claim 2 wherein said pin means comprises a first pin pivotally connecting said measuring rod to said frame and second pin means pivotally connecting said frame to the propeller housing along an axis at right angles to the axis of said first pm.

lower end and its point of connection to the propeller housing for varying the length of the measuring rod in response to variations in the distance between its lower end and propeller housing connection.

6. In an apparatus as claimed in claim 5 wherein said length varying means comprises a telescoping connection between two portions of said measuring rod.

Claims

1. In an apparatus for indicating the position of means defIning a center of eccentricity of a blade of a actuating mechanism blade wheel propeller in which the direction of thrust is perpendicular to a plane passing through the center of eccentricity and the rotary axis of the propeller, said propeller comprising a control member mounted at its central portion for universal tilting movement and having a lower end pivotally connected to the center means and an upper end, a pair of servomotors mounted on the propeller housing at right angles to each other and pivotally connected to the upper end of said control member, a measuring rod having a lower end pivotally connected to the upper end of said control member and fastened to the propeller housing at a point spaced from its lower end, and means responsive to the movement of said measuring rod as it moves in response to said control member for accurately indicating variations in the position of said center means with respect to the rotary axis of the propeller.

2. In an apparatus as claimed in claim 1 and comprising means including a frame firmly connected to the propeller housing for gimbal mounting said measuring rod at said point spaced from its lower end, potentiometer means, said gimbal means comprising pin means non-rotatably connecting said measuring rod and said frame to said potentiometer means whereby the angles of twist of the respective pin means are sensed to indicate the position of said center means.

3. In an apparatus as claimed in claim 2 wherein said pin means comprises a first pin pivotally connecting said measuring rod to said frame and second pin means pivotally connecting said frame to the propeller housing along an axis at right angles to the axis of said first pin.

4. In an apparatus as claimed in claim 1 wherein said measuring rod is firmly secured to the propeller housing at said point spaced from said lower end, and foil strain gage means mounted on several measuring points on said measuring rod for indicating strain variations on the measuring points on said measuring rod in response to the movement of said control center.

5. In an apparatus as claimed in claim 1 and means on said measuring rod between its pivotally connected lower end and its point of connection to the propeller housing for varying the length of the measuring rod in response to variations in the distance between its lower end and propeller housing connection.