The present invention generally relates to a propeller by internal mechanism in hub, in order to controllable changing thrust vector.

The more particularly the invention relates to a propeller for use in submarine which needed to change of direction frequently,

Background Of The Invention:

The main profession of the Marian propellers is to produce a thrust force for leading the ship or the submarine. Some propellers in addition to produce a thrust force are able to change its vector. These kinds of propellers also, have different types like VSP (Voith Schneider Propeller] and CVP (Cyclic Variable Pitch Propeller] which respectively are used for the towboats and helicopter propeller. The applications of these propellers (VSP and CVP] are completely different. So, it is not possible to compare these kinds of propellers to this invention. In fact, the groundwork of this invention is different from that of the previous propellers. In previous patterns such as CVP propellers, the pitch angle of each blade changes during a cycle to change the Thrust vector. Each blade produces a specific amount of thrust force in every pitch so; the cyclic change of the pitch means a difference between the thrust forces in two sides of the propeller. This difference of force produces a torque which causes the direction of the submarine to change. In this kind of propellers, each blade has a rotational degree of freedom that its axle is perpendicular to the axle of the propeller's shaft. Therefore, the change of the relative angle of each blade means changing its pitch angle. The document US 2850106 A is an example of this propeller. But in this invention (when the Thrust vector is changing] the degree of freedom for every blade such as CVP pattern is rotational but its axle has the same direction with the axle of the propeller's shaft Rotation of every blade causes the angular velocity of that blade to differ from other blades. When the propeller completes a cycle, during rotation in a half, the angular velocity of the blades is reduced in comparison to the other half so; the thrust force varies from one side to the other side. This torque causes the ship or the submarine to shift. The document US 5466177 A have another pattern in which the degree of the blade's freedom is similar to our invention but it is used just for changing the amount (and not the direction] of the Thrust vector. In fact, it changes the amount (and not the direction] of the Thrust vector in a cycle by rotation of the blades (which all rotate together, with the same amount and unchanged in a cycle].

Currently, a submarine needs to rudder for changing direction, But rudder can't give acceptable maneuver to the submarine. Other harmful effect rudders provide turbulent, inlet fluid to propeller. So by used this invention and removed rudders, thrust generated have much more.

Object Of The Invention:

It is a object of the invention to provide a propeller that ameliorates maneuvering ability submarine or ship and with removed rudders eliminates disadvantages use it.

The summary Of the Invention:

This invention is a propeller which produces the thrust and also can shift its vector. The propeller's function is in such a way that each blade distinctly has a role for producing the thrust and also it has a rotational axle which is parallel to the propeller's shaft but in a different direction. When the thrust vector has the same direction as the propeller's shaft, the blades are fixed and immobile, but when it is needed to veer, the blade will rotate in various phases in relation to the hub. In this situation, there are two semi cycles. One of them is fast and another one is slow and each one is equal to the 180 degrees of the hub rotation. The blades in the fast semi cycle in relation to the hub have the angular velocity which has the same direction as the angular velocity of the hub in relation to the ground. In the slow semi cycle, this angular velocity in relation to the hub is in the opposite direction to the angular velocity of the hub in relation to the ground. Therefore, for having more absolute angular velocity, further lift is produced in the slow semi cycle and also, there is less lift in the fast semi cycle, for having less absolute angular velocity. In this position, there are two blades in the slow semi cycle whereas there is one blade in the fast semi cycle. As it is clear, difference between lifts causes to produce the torque and to shift the thrust vector, also difference between the Pressure drags on the blades in the both semi cycles produces extra torque for shifting the thrust vector. So, there is no need to use the rudders for veering. Absence of the rudders decreases the drag and makes the input follow to the propellers steady. For having this condition of movement, the blades are conducted by the mechanism of the rollers and the circular rails and this conduction is ordered by the hydraulic cylinders of the propeller's hub. The propeller's shaft has two pieces, its shell is used for transmission and central shaft which is fixes is used for holding the controller mechanism. So, the propeller can be more efficient and if it is needed, suddenly shift the thrust vector and give High maneuverability to the submarine.

Brief Description of the Drawings:

Fig. 1 is an isometric view of the propeller.

Fig. 2 is a blade position during a full cycle steps.

Fig. 3 is a chart blade position during a full cycle.

Fig. 4 is a sectional view of the propeller.

Fig. 5 is an assembly drawing of the fixed parts.

Fig. 6 is a longitudinal sectional view of the shaft sell for understanding transmission.

Fig. 7 is an assembly drawing of the blade and internal parts. Description of the Invention:

This pattern actually is a new kind of the Marian propellers whose groundwork is to change the instantaneous rotational velocity of the blades, in such a way that each blade has a specific rotation degree of freedom whose rotation axle has the same direction whit the axle of the propeller, every blade separately can rotate in relation to the propeller's plug. The amount of this rotation is variable from—51 ^° to +29 ^° . When the propeller is located in a normal state, the thrust vector has the same direction whit the axle of the propeller but, when we need to change the direction, the rotation velocity of the blades changes in relation to each other. This change of velocity is completely controlled, for example if we want to lead the Thrust vector to the left side (propeller is right hand], the rotation velocity of the blades on the right half is decreased but, the rotation velocity of the blades on the left half is increased. Changing the angles of the blades in relation to the propeller's plug causes these decrease and increase. When a blade reaches to the highest position of a cycle, its relative angle is— 51 ^° and this blade should change the relative angle to +29 ^° until it reaches to the lowest position of the cycle. In a half of a cycle, each blade in normal position rotates to 180 ^° but, considering the relative change caused by the rotation of the blade's axle,—80 ^° in the right half and also +80 ^° in the left half should be added to the 180 ^° of the rotation. Finally, each blade passing over the right half rotates 2.6 -fold slower than the blade passing over the left half. These changes cause a difference between the thrust forces in two sides of the propeller; therefore it changes the submarine's direction. Fig. 3 shows the relative angle of a blade during a cycle. A working cycle has been divided to the step sizes with 300 along Θ axis. The amount of the relative rotation of each propeller is shown by the axle located along r axis. This position has been arranged to turn the Thrust vector to the right There is a considerable point that the minimum of this angle's changes and also its maximum has been entirely controlled by a mechanical mechanism and they change according to our needs, in other words, how much the change of the needed direction in the submarine is more intensive, the difference between the minimum of the rotation angle and its maximum should be more.

For better comprehension, in fig.2 the rotation steps of a hub cycle when the thrust vector shaft, is shown. The situation of every propeller at the angel of the hub's location is shown. The hub's angel is created on the top of every propeller. The large arrow drawn out of the propeller shows the direction of the hub's rotation in relation to the ground and the small arrow drawn in the blade shows the direction of the blade's movement in relation to the hub. These two arrows are added to each other in the right semi cycle and are subtracted from each other in the left semi cycle.

Fig.4 shows the sliced view of the propeller. For better comprehension, the two detachable parts of the inner mechanism of the hub are separated from each other. This propeller has two parts: the fixed part and the rotating part. The rotating part includes the hub shell 103 and the shaft sell 105 which are coupled together by the screw 104. The blades 101 are connected to the hub and can rotate freely in their places. When the hub rotates they rotate too. Fig.7 shows the fixed part which includes a bowl- like part 110, hydraulic cylinders 109, the central shaft 107 and the bearing 108. The main function of the fixed part is to determine the bowl's location. This bowl moves on the XY plane and along the indicated direction 155. It controls the blades. Some rollers 122 are in the bowl and come into contact with its inner surface 156. Each of these rollers controls one blade's situation. This contact is continued during the movement, because when the propeller is rotating, the reaction force inputted into the blade by the water during the rotation, is inputting a torque into the blade in the opposite direction of the hub's rotation. So, the rollers remain to contact the inner surface, but when the direction of the propeller's rotation is reverse, the rollers rotate in the opposite direction and come into contact with the upper surface of the bowl 154. The bowl's mouth is just in a size that the rollers can enter it so; there is no problem with assembling the mechanism. The bowl's transferring on the plane is in such a way that every blade can move in the range of 51< < < 29. On the back of the bowl there is a cube 155 with four tracks 119. These tracks are completed by a part 116. Four screws which pass the cube's holes and are screwed in the cube, connect this part to the cube. Some cylindrical sliders 124 can freely move in the track. They are connected to the cube 4 by a screw 135 which passes the piston 122 and is screwed to the holel23. This piston 4 is placed in the cylinders. There are some seals 132 on the cylinder's lip and also, there is an oring 121 on the piston's lip to prevent the oil from leaking out. There is a leak at the bottom of the cylinder for entering or flowing out the oil. This leak has been connected to the back of the cylinder 134 by a connector 136 which connects the cylinder block to the central shaft. It connects also, the shaft's leaks which are used for passing the oil 106 to the holes which are at the back of the cylinder. The central shaft should be coupled with a stable part of the submarine or the ship 159. So, it can be related to the hydraulic hoses 157. The shaft's leaks which are used for passing the oil are connected to the hydraulic hoses by four inlet valves on the shaft. The external shaft which rotates the propeller is placed on the internal shaft by two bearings 108. There is a gear 160 at the end of the external shaft which is engaged with another gear that is placed at the end of the engine's shaft. For having more space, this power transferring system can be embedded in the gearbox. Hydraulic Cylinder head 109 which is screwed 129 to the holel31 steers the piston and holes it in the suitable direction. The connector hydraulic of the block is connected by the screwl27 which passes the holel37 and is placed in the holel30. Also, the screw 128 passes the holel39 then it is fastened to the holel33. The orings 138 and 140 are placed in the holes 134 and 141 to prevent the oil from leaking out. The connector hydraulic 136 is placed in the shaft 107 and screwed 125 to it The part 113 is like a small shaft that allows the blade to rotate at the hub. When the shaft is fitted in blade, the spur 147 and its negative 146 which exist inside the blade are joined together. The inner surface of the bearing 144 is on the spur and the exterior surface is placed on the hub. A set of the multiple seals 145 is situated inside the blade to prevent the water flowing into the hub. A nut 102 fits the blade with the part 113. The end of the part 113 is threaded 143 and fastened to the holel52. The roller 112 and the screw 111 are fitted in the part 151. The part 151 is placed in the bearing 150 and this set becomes firm by the pin 149 and is placed in the holel48.

Industrial viewpoint

There are some other mechanisms to control the bowl 110. Instead of the fixed central shaft, a sliding shaft which has both linear and rotational degree of freedom should be used. Also, there should be a jack and a hydraulic engine to control the sliding central shaft. A sliding rail connected to the shaft should be designed for the bowl to move in radial direction in relation to the shaft. When the shaft rotates around itself, the bowl will rotate too. There is a crank which joined to the bowl from one side and to the sliding central shaft from the other side. When the sliding central shaft moves forward, the bowl gets away from the center. So, the bowl can be controlled by this mechanism. Using this mechanism makes it possible have a jack and also a hydraulic engine where the hydraulic hoses are now assembled without any change in the hub's volume. So, this mechanism changes the volume of the bowl's controller, therefore it is rejected. Another form is to use the servo motor and the ball screw instead of the hydraulic jacks in the hub. For lack of volume in the hub, this mechanism is not durable toward the forces which the blade input into the bowl. So, it will be early damaged. Another form is to use the crank mechanism instead of the mechanism of the roller and the bowl. For it, two cranks which are joined together should be used. One of the cranks is connected to the blade's shaft and the other is joined to an axle. These two cranks can't have the same direction. This mechanism lengthens the hub so; it causes lack of symmetry of the mechanism which will create some problems.

Therefore, using four cylinders for the hub, as used in this invention, in addition to considerably decrease the mechanism volume and to make the propeller's hub smaller, it creates high precision and durability to control the bowl.