US2015514A

US2015514A - Device for the control of motion of movable blades on blade wheels

Info

Publication number: US2015514A
Application number: US12670A
Authority: US
Inventors: Ehrhart Josef
Original assignee: Voith Schneider Propeller Co
Current assignee: Voith Schneider Propeller Co
Priority date: 1934-03-26
Filing date: 1935-03-23
Publication date: 1935-09-24
Anticipated expiration: 1952-09-24
Also published as: AT146547B; GB438317A; DK51513C; DE638318C

Description

p 1935 i J. EHRII-LIAIRT 2,015,514

DEVICE FOR THE CONTROL OF MOTION OF MOVABLE BLADES ON BLADE WHEELS Filed March '2; 1955 s Sheets-Sheet 1 F -,M=-,, ....................v.............. I ulnlnnn.1ZZAWWI"UHHH,A 'nnz aoseeammmr J. EHRHART Sept. 24, 1935.

DEVICE FOR THE CONTROL OF MOTION OF MOVABLE BLADES 0N BLADE WHEELS Filed March 25, 1935 5 Sheets-Sheet 2 mwemom .beseF evmwm Sept. 24, 1935. J. EHRHART DEVICE FOR THE CONTROL OF MOTION OF MOVABLE BLADES ON BLADE WHEELS 3 Sheets-Sheet 3 Filed March 25, 1955 bNVENT R (5052? EM! NIT y Q W kflo n FX- I Patented Sept. 24, 1935 navron' ron'rnn mm. or Morton or MOVABLE BLADES on nmnn WHEELS Josef Elli-hart, Heidenheim-on-the-Brcnz, Germany, assignol' to Voith-Sclmelder Propeller Company, New York, N. Y., a corporation of New York Application March 23, 1935, Serial No. 12,670 In Germany March 26, 1934 11 Claims. (or. 170-148) .the objects of the invention is a simplification o the means of control for the blades.

known. They operate either with an imaginary Figures 2 is a S ct o 011 line 0 1;

steering center or with a material steering center, Figure 3 is a plan vi w d a a a y sh w 15 which material steering center is provided with similar to Fig. 1, but Showing the blades in rods which are connected with the blades so as to Pos on Corresponding to e o d em nt operate or shift the blades, depending upon the of the blade wheel when used as a Propulsion position of the steering center. means of a ship.

This form of embodiment results in a relatively Figure 4 is a plan view of another embodiment 20 high structure in the center part of such blade also diagrammatically shown; wheels, and in an unsatisfactory distribution of Figure 5 is a diagrammatic representation of forces acting upon the steering center, and also in the movement of the operative parts of a blade,

that such an arrangement in different planes relative to the rotor;

necessitates special construction of the rods and Figure 6 is a perspective view of a practical em- 25 connecting links. bodiment of the invention herein described;

More particularly, the invention consists in Figure 7 is a vertical central cross section of one arranging the connecting means between the of the above embodiments with an electric problades and the steering center substantially in a p n m ns combined h w h; nd

'plane at right angles to the axis of rotation of the Figure 8 is a plan view of Fig. '7. blades. By this arrangement, simplification in Referring to the drawings and more particularthe manufacture, in the installation and in the lyto Figures 1 and 2, the blade wheel or rot'or l0 operation is obtained, and a very compact struchas its axis ll of rotation centrally disposedln ture results. respect thereto. A plurality of blades l2 are In an embodiment of the'invention hereinafter suitably supported by blade wheel in in movable 35 shown, each blade is connected with the steering position in respect thereto and the position of center by means of a rod, guided in a linear directhe blades shown in Figure 1 is in zero or tangention, by a guide block rotatably fixed upon the tial position corresponding'to the stop posi- 40 blade wheel or rotor, said guide block determining tion. In the central part of the blade wheel,

" 'the angular movement of the blades, since they a steering center plate I5 is arranged, which is 40 are also connected with an eccentrically adjusrotatably connected with a ball I 6 of the lever I! table member or steering center plate, which when pivoted at [8 in the socket l9, permanently held. placed in the concentric position places the axis to the blade wheel hub 20, as shown in Figure 2.

of the horizontal profile of the blade tangential By moving the lever H, the plate 15' is moved in to the circle of rotation, corresponding to a proany-direction and the transposed position of the 5 peller pitch of zero, the rods for all blades being plate I5 is clearly shown in Fig. 3, wherein the arranged in the same radial plane. plate I5 is eccentrically disposed to the axis ll The invention consists further in combining the and the blades are shown angularly displaced in structure set forthwith an electric propulsion respect to the position shown in Figure 1. The

means, part secured to the blade wheel rotor and lever I! may be operated either by hand or by 50 part to the housing, this combination being made 4 any suitable device well known in the art and possible by'the compact arrangement resulting not shown in th drawings, I Figure 7, servofrom the arrangement of the before mentioned motors 41 are utilized. The steering center plate rods.

This invention relates to devices for the control of motion of movable blades on blade wheels in which the axes of the blades are parallel or substantially parallelto the axis of the rotor. One of It is known that in accordance with hydraulic principles, the correct relative movement of suchblades in respect to the blade supporting body or blade wheel is then attained, when the normals to.

The invention further provides specially advantageous means of overcoming certain operative deficiencies which will be pointed out hereinafter.

Embodiments of the invention will be hereinafter described and shown in the drawings, and will be finally set forth in the appended claims.

In the drawings, in which same reference characters indicate same parts, a

Figure 1 is a plan view diagrammatically shown, of a blade wheel with six blades and'the connecting rods thereon for operating the blades during the rotation of the blade wheel, the blades being shown in their zero or tangential position, or in stop position;

I5 is moved'in both dimensions of the radial plane and may take any position in respect thereto. The steering center plate I5 is connected by means of a pivotal connection 2I with a slide rod 22. Each of these slide rods 22 is connected with the blade wheel I0 by a guide block 23, the ends of which engage

suitable recesses

24 and 25 in the

plates

26 and 21 of the blade wheel. The guide blocks 23 being rotatably held in their recesses, do permit the slide rods 22 to slide therethrough, in a straight line direction.

Such plates

26 and 2? form a compartment of relatively small depth, in which the steering center plate I5 and the slide rods 22 and the other parts about to be described are arranged. Each of the slide rods 22 is pivotally connected with links 29 by the connection 30, and the free ends of the links 29 are connected with the blades I2 through the pivotal connection 3|, andthe blade lever 32, which blade lever 32 is suitably secured to the blade stem 33 of the blade I2. The movement of the pivotal point 30 then determines the angular position of the blade I2 in respect to a circle 35 shown in dotted lines'in Fig. l, which circle 35 indicates the path of the blades as they rotate. The pivotal connection 30 may be -made in the form of a shear pin easily broken when the strain is too large. Any suitable safety breaking de vice may be utilized. The steering plate I5 ro-,- tates with the rotor I0, and to effect this retation of the steering plate in the embodiment shown in Figure 1, the steering plate I5 is integrally extended by means of the bar 36 which at its free end has a sliding connection 31 with a stud 38 secured to the blade wheel. The relative movement between the fork-shaped end 3T and the stud 38 must be such that the largest possible movement of the steering plate I5 in any direction in its plane at right angles to the axis II will be permitted.

It will be noted that as the steering center plate I5 is moved into eccentric position as shown in Figure 3, the slide rods 22 slide in the guide blocks 23, and their free ends take diiferent positions. The straight line movements of the slide rods 22, move the pivotal connection 30, and in consequence the links 29, and thereby the blade levers 32 and blades I2, whereby the blades I2 are angularly shifted.

In the embodiment shown in Figure 4, the same parts just described are utilized save'that the bar 36 is omitted and the rotation of the steering center plate I5 is obtained by rigidly connecting with the plate I5 one of the slide rods which is marked in Figure 4 with the reference 39. This is in turn connected with the link 29, blade lever 32 and blade I2, and in consequence as the blade wheel I0 rotates, the steering center plate I5 is rotated therewith.

In the described forms wherein the steering plate I5 is carried along by the blade wheel and rotated therewith, it will be noted that the movement of the former is not with a constant angular velocity, but with a variable one. It is possible to so arrange the coupling between the blade wheel and the steering center plate that both parts rotate always with equal angular velocity,

but whatever advantage may result therefrom would be overcome by an unnecessarily complicated construction of the parts. From a practical standpoint the described coupling devices between the blade wheel and the steering center plate satisfy all practical conditions; it is selfevident that certain deviations of the parts of the control mechanism among each other result, depending upon their relative position to the coupling rod 36 in Figure 1 and 39 in Figure 4. The lengths of the links 29 differ somewhat from each other, and the guide blocks 23 do not rest in a circle around the axis II of the rotor III,

as this would be the case with an exact coupling 5 tachment of links 29 on the steering center plate I5, through the slide rods 22 are all in one and the same plane, so that the smallest possible construction height as also the most advantageous 20 stress distribution upon the steering center plate are obtained. The described device has also certain further advantages inasmuch as the throw of the blades is influenced in such a manner as has not been possible with heretofore known mechani- 25 cal control devices used in similar blade wheels.

In the devices heretofore proposed, the point moving in a straight line was always fixed to the steering center or steering center plate and the free end of the connecting rod was pivotally con- 30 nected with the rotating rotor. In consequence, the throw of the blade was always proportional to the throw of the connecting rod and the blade reached its largest throw exactly in the same point of time as the connecting rod. Kinematic 35 researches of the law of movement have shown that the two greatest amplitudes of the blade must follow each other in point of time all the quicker, the larger the propeller pitch is. In consequence thereof, the devices heretofore proposed caused 40 considerable difiiculties so when blade wheels of great pitch were constructed, the entire mechanism including the connecting links had to be designed for largest' amplitudes quickly following each other, whereby large accelerating forces and 45 unfavorable lever ratios were unavoidable.

In the arrangement in accordance with this invention, the point moving in a straight line is fixed to the blade wheel, whereby a periodic change of the speed ratio between the angular 50 movements of the rod 22 and the blade lever 32 takes place and in such a manner that the positions of the blade at their greatest throw follow quicker upon each other in point of time than those of the slide rod 22. The diagram shown in 65 Figure 5 shows in diagrammatic form these advantageous relations. The change in the speed ratio comes exactly into being in that the free length 40 of the slide rod 22 changes itself periodically so that the velocity of the point of 60 the pivotal connection 30 becomes in certain positions of the device particularly large which, in

point of time, corresponds to the largest amplitudes quickly following each other. These relations are obtained when the device is so executed 65 or constructed that in a central or concentric position of the steering plate I5, the length of the slide rod 22 through it straight line guide is so divided, that the distance between the axis of V the inner pivotal connection 2I and the point 23 70 is one-half to one-third of the total length of the rod 22; as the pivotal point 30 takes different positions along the diagram or curve II the pivotal point 3| moves in correspondence thereto, the points a, b, c, d, e, and 1, a", b, c, d, e, 1" and 76 a", b", c", d", e" and 1'', indicating like positions.

The compact construction of the device for the control of motion for movable blades on blade wheels described hereinabove, permits its combination with an electric motor, and, enables the assembling structure to be built of specially strong elements to correspond with the demands made by large diameter structures. pellers it has been customary heretofore to use a horizontal shaft along the length 01' the ship, and connect this shaft with the vertical shaft of the blade wheel propeller. In other cases where a vertical shaft was dispensed with, the horizontal shaft was connected by gears to the rotor of the propeller laterally of the axis of the propeller. An embodiment of this form is shown in my copending application, Serial No. 716,018 filed March 17, 1934. In contrast to these forms of mechanical transmisions, I the present form of compact blade actuating mechanism enables electrical mechanism to be installed, so as to drive the blade wheel in a very simple manner.

In Figure 7, an embodiment of this invention is illustrated, in which the blade wheel l0, blades [2, blade shifting mechanism for the blades generally indicated by 45, steering center operating mechanism generally indicated by 46, -a servomotor ll of known construction to operate the lever 46, are shown. The blade wheel housing 48 is provided with an extension 49, to which is se-- cured anopen electric rotor ring 5ll. Within this rotor 50, an electric stator 5| is secured to the stationary housing 52. Where electric current obtained from a suitable source of supply, is used to energize the coils of the electric rotor and stator, the ring it is rotated, and in consequence the blade wheel is rotated. It will be particularly noted that the propeller blade wheel has no shaft orits equivalent or any driving means, since the peripheral electric rotor and stator rings exert the propelling force to rotate the blade wheel. Either direct or alternating current can-be used. This electrical installation is comparatively simple since the blade wheel rotor rotates with constant speed which simplifies the wiring and switchboard arrangement. It will also be'noted that the stationary housing 52 extends downwardly into a bell-shaped portion 53 which supports suitable anti-friction bearings, the rotatable blade wheel which rotates by the aid of anti-friction bearings 55 around a central hub 55, which is supported by the frames 56. Theonly operative part of the mechanism for shifting the blades is the lever 48 for shifting the steering center plate,which lever in turn is operated in the embodirnent shown by the servomotor- 41. This servomotor 47 and part of the lever 46, are disposed within the electrical stator ring 5| and rotor ring 55. Thus the open interior of' the electrical rings permits the steering mechanism to be located therein, whereby the entire device as described is self-contained and may be installed with simplicity of operation, having all the advantages of electrical operation.

My invention has been illustrated and'described with some degree of particularity, but it is understood that changes may be-made in the form of details and in the construction and arrangement of parts without departing from the spirit and scope of the invention or the scope of the appended claims.. 7

I claim:

1. A device for the control of motion of movable blades on blade-wheels, in which the blade In blade wheel pro-.

axes are substantially parallelto the axis of the blade wheel, blade controlling means for a blade wheel having blades, including a steering center plate rotating with said blade wheel and shiftable in any direction in a plane perpendicular ii to the axis of the blade wheel from a position concentric and corresponding with zero pitch of the blades to a position eccentric to said axis, and connecting means between said steering center plate and each blade including a rod for each 10 blade pivoted to said steering center plate, guide means for said rod for guiding the same in straight line movement for controlling the angular motion of the blade.

2. A device for the control of motion of mov- 15 necting means between said steering center plate 26 and each biadeincluding a slide rod for each blade pivoted to said steering center plate and guide means for said rod for guiding the same in straight line movement by said blade wheel, and

a link pivoted at one end to the free end of said slide rod and pivoted at its other end to one of said blades. v

3. A device for the control'oi motion of movable blades on blade wheels, in which the blade axes are substantially parallel to the axis of the blade wheel, control means for a blade wheel having blades, including a steering center plate. rotating with said blade wheel and shiitable in any direction in aplane perpendicular to the axis of the blade wheel from a position concentric 4o and corresponding withhero pitch of the blades to a position eccentric to said axis, connecting means between said steering center plate and each blade including a rod for each blade pivoted to said steeringpenter plate and guide means for 45 guiding the rod in straight line movement, said guide means comprising a guide block rotatably mounted in said blade wheel for guiding the slide rod in straight linemovement, and a link pivoted at one end to the free end of said slide 5 rod and pivoted atits other end to one of said blades.

4. A device for the control of motion or movable blades on blade wheels, in which the blade axes are substantially parallel to the axis of the 55 blade wheel, blade controlling means for a blade wheel having blades, including a steering center plate rotating with said blade wheel and shiftable in any direction in a plane perpendicular to the axis of the blade wheel from a position con- 0 centric and corresponding with zero pitch of the blades to a position eccentric to said axis, connecting means between said steering cen er plate and each blade including a rod for each blade pivoted to said steering center'plate and guide means for guiding the rod in straight line move- A ment, said guide means comprising a guide block for guiding said rod, said guide block being disposed in respect to the inner end of said rod a distance oi one-half to one-third of the entire op- 7 erative length of said rod.

5, A device for the control of motion or movable blades on blade wheels. in which the blade axes are substantially parallel to the axis of the blade wheel, blade controlling means for a blade 75 wheel having blades, including a steering center plate rotating with said blade wheel and shiftable in any direction in a plane perpendicular to the axis of the blade wheel from a position concentrio and corresponding with zero pitch of the blades to a position eccentric to said axis, connecting means between said steering center plate and each blade including a rod for each blade pivoted to said steering center plate and guide means for guiding said rod in straight line movement, and means for securing the steering center plate to said blade wheel, including a bar secured to said plate and to the blade wheel.

6. A device for the control of motion of movable blades on blade wheels, in which the blade axes are substantially parallel to the axis of the blade wheel, blade controlling means for a blade wheel having blades, including a steering center plate rotating with said blade wheel and shiftable in any direction in a plane perpendicular to the axis of the blade wheel from a position concentric and corresponding with zero pitch of the blades to a position eccentric to said axis, connecting means between said steering center plate and each blade including a rod for each blade pivoted to said steering center plate and guide means for guiding said rod in straight-line move ment, and means for securing the steering center plate to said blade wheel, including a bar secured 'to said plate and to the blade wheel, said bar blades to a position eccentric to said axis, connecting means between said steering center plate and each blade including a rod, for each blade pivoted to said steering center plate and guide means for guiding said rod in straight line movement, and means for securing the steering center plate to said blade wheel, including a bar secured to said plate and to the blade wheel, said bar having a sliding connection with a stud on the blade wheel, the last named bar being so arranged that the steering center plate rotates with a constant angle of velocity.

8. A device for thecontrol of motion of movable blades on blade wheels, in which the blade axes are substantially parallel with the blade wheel axis, comprising unitary structure consisting of a steering center plate movable in a plane perpendicular to the axis of the blade wheel, and rotatable with the blade wheel, sliding rods pivoted to said plate, guide means for guiding links disposed between the free ends of said slid- 9. A device for the control of motion of mov- 5 able blades on blade wheels, in which the blade axes are substantially parallel with the blade wheel axis, comprising unitary structure consisting of a steering center plate movable in a plane perpendicular to the axis of the blade wheel, 10 and rotatable with the blade wheel, sliding rods pivoted to said plate, guide means for guiding said sliding rods for movement in straight line direction by the said plate, and having means adapted to be connected with the blade wheel, and to be 15 rotatable therewith, blade moving means adapted to be attached to the blades, links disposed between the free ends of said sliding rods and the blade moving means of said parts, the plate, the sliding rods, the blade moving means and the 20 links being disposed substantially in one plane, and fastening means for rotating all of said parts with said blade wheel.

10. A device for the control of motion of movable blades on blade wheels, in which the blade 25 axes are substantially parallel with the blade wheel axis, comprising unitary structure consisting of a steering center plate movable in a plane perpendicular to the axis of the blade wheel, and rotatable with the blade wheel, sliding rods pivot- 30 ed to said plate, guide means for guiding said sliding rods for movement in straight line direction by the said plate, and having means adapted to be connected with the blade wheel, and to be rotatable therewith, blade moving means adapted 35 to be attached to the blades, links disposed between the free ends of said sliding rods and the blade moving means of said parts, the plate, the sliding rods, the blade moving means and the links being disposed substantially in one plane, 40 and fastening means for rotating all of said parts with said blade wheel, the said means adapted to be connected to the blade wheel being disposed along the length of the sliding rods at about onethird or one-half of their lengths, and the links 45 being of difierent lengths.

11. In'combination, with a device for the control of motion of movable blades on blade wheels. in which the blade axes are substantially parallel to the axis of the blade wheel, including a steer- 5 ing center plate movable with said blade wheel and shiftable in any direction in a plane perpendicular to the axis of the blade wheel from a position concentric to eccentric to said axis, connect ing means between said steering center plate and 55 4 on said housing, an electrical open ring rotor secured to said flange, a stationary housing, a flange on said stationary housing,-an electrical open ring stator secured to said flange of the stationary housing, and means for operating the steering center plate arranged within the open 65 space of said electrical ring rotor and stator.

- JOSEF EHRHART.