|Publication number||US3349744 A|
|Publication date||Oct 31, 1967|
|Filing date||May 17, 1966|
|Priority date||May 31, 1965|
|Publication number||US 3349744 A, US 3349744A, US-A-3349744, US3349744 A, US3349744A|
|Inventors||Bernard Mercier, Jean Mercier|
|Original Assignee||Jean Mercier|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (1), Referenced by (30), Classifications (6)|
|External Links: USPTO, USPTO Assignment, Espacenet|
Oct. 31, 1967 J. MERCIER ETAL 3,349,744 HYDRAULIC CONTROL SYSTEM FOR RUDDERS AND/OR 1 DEFLECTORS OF A SHIP Filed May 17, 1966 3 Sheets-Sheet. 1
O I'NVENTORS I) JEAJJ NERR Y EEKAJAQ [1549054 1,4 ATTORNEY J. MERCIER ETAL HYDRAULIC CONTROL SYSTEM FOR RUDDERS AND Oct. 31, 1967 3 Sheets-Sheet 2 Filed May 17, 1966 DEFLECTORS OF A SHIP INVE-NTORQ Jzau He'kuefl Geaumlo M52062 BY Z a ATTORNEY 3 1967 J. MERCIER ETAL 3,349,744
HYDRAULIC CONTROL SYSTEM FOR RUDDERS AND/OR DEF'LECTORS OF A SHIP Filed May 17, 1966 3 Sheets-Sheet v5 20 FIG.3
I INVENTORS J EA u HQ Quqrz (Seam/W0 HGQuEf Mara;
ATTORNEY United States Patent 8 Claims. 61. 114-150 As conducive to an understanding of the invention, it is noted that ships at times have either two or more rudders which permit better maneuvering within a small radius than when only one rudder is provided, or a rudder associated with deflector means which are a sort of orientable guides of a construction similar to that of a rudder, placed in front of the driving means of the ship, for instance the propeller means, and intended to improve the conditions of incidence of the fluid streams as a function of the position of the rudder, or else one or more rudders and one or more deflectors.
As is known, while a single rudder can be maneuvered without special difliculty in most cases, nevertheless when the ship is provided with at least two rudder and/or deflector means, it is advisable to coordinate the various movements of said means with respect to each other in a manner which will satisfy not only the requirements of precision and ease of piloting, but also safety.
It is accordingly among the objects of the invention to provide a hydraulic control system for a ship having a plurality of rudders which insures dependable operation of said plurality of rudders in synchronization and which in the event of failure of the main power system permits manual actuation of said rudders.
According to the invention, the hydraulic control system has a pilot station, a hydraulic power source, a first rudder means controlled by said pilot station and having two hydraulic motors, one consisting of a pilot motor manually operated from the pilot station and the other of a booster motor fed by the said hydraulic power source under the control of a hydrovalve dependent on the pilot station, and at least one second rudder having at least one motor supplied by said hydraulic power source under the control of a distributor, the movements of which are subject to the movements of the first rudder means.
As a result of this arrangement, the plurality of rudders do not require any additional piloting force on the part of the helmsman. The energy necessary to actuate the rudders is developed in response to the manual maneuver exercised on the pilot motor alone.
More particularly, in accordance with the invention, the distributor associated with a second rudder has its control rod connected to the central pivot of a rocker lever, the two ends of which are connected respectively by connecting rods to the two rudders, at least one of said connecting rods being provided with an elastic centering device. The actuation of the distributor and its return means into a neutral position is effected by a two-directional mechanical transmission.
Furthermore, in accordance with the invention, safety means are provided to make it possible, continuously to maneuver the rudders in the event that the hydraulic power station should break down.
In accordance with one embodiment of said safety means in which the second rudder has a single hydraulic motor which can be operated by the hydraulic power source, a solenoid valve is interposed between the power source and the distributor associated with the said motor so as to block said second rudder in position and prevent it from shifting and interfering with the maneuver efiected manually by the single first rudder if the power plant breaks down.
In a variation of the safety means, said second rudder comprises not only a motor fed by the hydraulic power source, but also an emergency motor which can be maneuvered from the pilot station so as to displace the second rudder means in synchronism with the first rudder means in the event that the hydraulic power source should break down. This emergency motor is associated with a distributor associated with the first rudder and acting in a circuit which may, if desired, by means of a hand valve, be controlled at the pilot station.
It will be noted that the blocking valves of the rudder as well as the valve which places the control of the emergency motor maneuverable from the pilot station in the circuit may be controlled either manually or automatically as a function of the pressure of the hydraulic power source.
In the accompanying drawings in which are shown one or more of various possible embodiments of the several features of the invention,
FIG. 1 is a diagram of a hydraulic control system for the rudders of a ship having two rudders; and
FIGS. 2 and 3 are views similar to FIG. 1, but each relating to a different variant.
Referring now to the drawings, as shown in FIG. 1, the rudder control system of the ship comprises two rudders 10 and 10a. The shaft 12 of the first rudder is adapted to be actuated by two hydraulic motors 13 and 14, and the shaft 12a of the second rudder is adapted to be actuated by a hydraulic motor 13a. The hydraulic motors 13, 14 and 13a: are, for instance, of the rotary type, but they may be of any other suitable type, for instance of the piston and cylinder type. The motors 13 and 13a are of high power and are connected to a hydraulic power source 18 which will be hereinafter described in further detail, while the motor 14 is of lesser power than the motors 13 or 13a and is connected to a manual power source 19. The manual power source 19 positioned at the pilot station 20 of the ship, has a tiller or steering wheel 21 which cooperates with a closed hydraulic circuit having two conduits 22 and 23 connected to the small motor 14 in such a manner that when the tiller 21 is turned in one direction, it forces oil under pressure into the conduit 22 which causes the rotation of the motor 14 in one direction, the oil returning to the conduit 23, while when the tiller 21 is turned in the other direction, it forces oil under pressure into the conduit 23 which causes the rotation of the motor 14 in the other direction, the oil returning through the conduit 22.
A hydrovalve 24 of conventional type to which there are connected four conduits 25, 26, 27 and 28 is actuated by the pressures developed in two conduits 29 and 30 connected at 31 and 32 to the conduits 22 and 23 respectively.
The conduits 25 and 26 are connected to the motor 13 while the conduits 27 and 28 are connected to the hydraulic power source 18. The latter consists of a reservoir 33 into which liquid is discharged through the conduit 27, and fluid pressure means 34, 35 which feed the conduit 28. These fluid pressure means comprise, for example, a pump 34 which draws fluid from the reservoir 33 as well as a pressure accumulator 35.
The hydrovalve 24 is so arranged that when in neutral position both of the conduits 25 and 26 are closed while the conduits 27 and 28 are connected to each other. When the conduit 29 is under pressure and the conduit 30 is decompressed, the conduit 28 is connected to the conduit 25 and the conduit 26 is connected to the conduit 27. When the conduit 29 is decompressed and the conduit 30 is under pressure, the conduit 28 is connected to the con- .3 duit 26 and the conduit 25 is connected to the conduit 27.
Pivotally connected at one end as at 36 to rudder is a connecting link or rod 37 which includes a resilient centering device 38. The latter normally maintains the rod 37 at a predetermined length but under the influence of a substantial stress applied either in traction or in compression to the rod 37, it permits a temporary lengthening or shortening of the rod 37 and then once this stress has ceased, tends to restore the rod 37 to its predetermined length. The other end of the rod 37 is pivotally connected at 39 to one end of a rocker lever 40. Pivotally connected to the other end 41 of lever 49 is one end of a connecting link or rod 42, the other end of which is pivotaly connected at 41a to the other rudder 10a. The rocker lever 40 is pivoted at its center at 43 on a rod 44 which actuates a distributor valve 45.
Connected to valve 45 are four conduits 46, 47, 48 and 49. The conduits 46 and 47 are connected to the motor 13a, while the conduits 48 and 49 are connected to a solenoid valve 50. The latter is associated with two other conduits, one of which, conduit 51, is connected to the reservoir 33 of the power source 18 while the other conduit 52 is connected to the pressure means 34, 35 of the said power source 18.
The valve 45 is so arranged that when in neutral position, both of the conduits 46 and 47 are closed while the conduits 48 and 49 are connected to each other. When the end 39 of the rocker lever 40 is urged to the right by the rod 37, the conduit 49 will be connected to the conduit 46 and the conduit 47 will be connected to the conduit 48. When the end 39 of the rocker lever 40 is urged to the left by the rod 37, the conduit 49 will be connected to the conduit 47 and the conduit 46 will be connected to the conduit 48.
The solenoid valve 50 is associated with an electrical circuit 53 having a switch 54 located at the pilot station 20. When the switch 54 is closed, the solenoid valve 50 occupies a first position in which it connects the conduit 52 to the conduit 49 and the conduit 48 to the conduit 51. When the switch 54 is open, the solenoid valve occupies a second position in which it closes each of the four conduits 48, 49, 51 and 52. The switch is normally maintained closed so that solenoid valve normally occupies its first position.
The operation is as follows:
As long as the pilot does not change the position of the tiller 21, no fluid will fiow in the conduits 22, 23 and hence the small motor 14 will not be actuated and the conduits 29 and 30 will not be under pressure so that the hydrovalve 24 will be in its neutral position. Consequently, the large motor 13 will not be actuated and the rudder 10 will remain stationary. As a result, the rocker lever 40 will not be actuated and the valve 45 will occupy its neutral position so that the motor 13a will not be actuated and the rudder 10a will remain stationary.
When the pilot turns the tiller 21 in one direction to modify the heading, oil is forced under pressure into one of the conduits 22 and 23, for example, the conduit 22, which tends to cause the motor 14 to rotate in one direction. The resistance to movement offered by the rudder 10 causes the pressure to rise in the conduit 22 and also in the conduit 29. As a result, the hydrovalve 24 is actuated to connect the pressure conduit 28 to the conduit The motor 13, known as the main or booster motor, is therefore urged in the same direction as the motor 14 designated as the pilot motor 14, and the rudder 10 is displaced under the combined action of the two motors 14 and 13; to a slight extent by the pilot motor 14 controlled manually by the tiller 21 and to a greater extent by the booster motor 13.
The displacement of the rudder 10 reacts via the rod 37 on the rocker lever 40 which tends, by means of the connecting rod 42, to move the rudder 10a in the same direction. However, the resistance to movement offered by the rudder 10a causes the rocker lever 40 to pivot and shift the rod 44 in direction to actuate the valve 45 to connect the pressure conduits 52, 49 to the conduit 46. The motor 13a is actuated to displace the rudder 10a in synchronization with the displacement of the rudder 11).
It should be noted that the rod system 37, 40, 42 is of light construction and does not directly act, mechanically to connect the two rudders 10 and 10a to each other, but constitutes control means for sensing the relative position of the rudders 1t and 10a in order to actuate, if necessary, the control circuit for the rudder 10a to set its position as a function of the position of the rudder 10.
The points 12, 43, 36 and 39 form the corners of a deformable parallelogram and the points 43, 15, 41 and 41a also form the corners of another deformable parallelogram identical to the first and deforming simultaneously due to the rocker lever 40 so that the movements of the two rudders 10 and 1011 are in synchronization.
However, the first parallelogram 12, 43, 36 and 39 is not exactly a parallelogram due to a slight lateral shift of each of the pivot points 36 and 39 as can be seen in FIG. 1. This arrangement is adapted in imparting the rudders 10 and 10a slightly different inclinations upon turns so that their plane is perpendicular to the radius of the circumference described by each of them.
It will be noted that in the arrangement above described with reference to H6. 1, the first rudder 10 is controlled by the pilot station 2t) while the second rudder 18a is controlled by the movement of the first rudder 10 and not directly by the pilot station 28.
In order to make certain that the second rudder 10a accurately follows the swings of the first rudder it), it is necessary that the drive torque acting on the rudder 19a be a sufficient amount higher than the resistant torque of the said rudder 19a.
This result is obtained by a compensating tang 11a of the rudder 10a which is of suflicient length to increase the counterbalancing of said rudder and, therefore, to decrease its resistant torque. For example, the compensating tang 11a of the rudder 10a can be made slightly larger than the compensating tang 11 of the rudder 10. If desired, the blade part proper of the rudder 10a could be made smaller in size.
Instead of decreasing the resistant torque, it is possible to increase the driving torque and, with a power plant 18 of one pressure level, provide a motor 13a more powerful than the motor 13 or else, with a power plant 18 of two pressure levels, assign the highest level to the motor 13a.
If the power plant 18 should fail, the pilot can continue maneuvering the rudder 10 by the tiller and with the assistance of the motor 14 alone, but the rudder 10a is no longer controlled and can assume any position which might interfere with the manuever.
In order to avoid this drawback, the solenoid valve 50 is provided. In case of failure of the power plant 18, the pilot opens the switch 54 which closes each of the four conduits 48, 49, 51 and 52. Thus, the motor 13a is hydraulically blocked and the same is true of the rudder ltla which can no longer interfere with the maneuver. The elastic centering device 38 absorbs the discrepancies of the system of rods 37, 48, 42.
In the embodiment shown in FIG. 2, the arrangement is similar to that shown in FIG. 1, but the second rudder 10a, instead of being held blocked in case of breakdown of the power plant 18, is permitted to be maneuvered manually at the same time as the first rudder 10.
In FIG. 2, the solenoid valve 50 is eliminated and the conduits 51 and 52 connected to the power plant 18 are directly connected to the valve 45.
The shaft 12a of the second rudder 10a is equipped not only with the motor 13a but with another motor 14a of smaller power, known as the emergency motor.
The pivot 43 acts not only on the rod 44 of the valve 45, but also on the rod 60 of a distributor valve 61, which is located symmetrically.
Four conduits, 62, 63, 64 and 65 are connected to valve 61. The conduits 62 and 63 are connected to the motor 14a while the conduits 64 and 65 are connected to a manually controlled valve 66 located at the pilot station 20. The valve 66 is associated with two other conduits 67, 68. The conduit 68 is connected to a reservoir 69 while the conduit 67 is connected to the conduits 22 and 23 respectively by two non-return valves 70 so that the pressure always reaches the distributor 61 through the same conduit 65. The valve 61 is so arranged that when the rocker lever 40 is not urged at 39, it occupies a neutral position in which the conduits 62 and 63 are connected and the conduits 64 and 65 are connected. When the rocker lever 40 is urged in one direction the conduit 64 is connected to the conduit 62 and the conduit 63 is connected to the conduit 65, and that when the rocker lever 40' is urged in the other direction, the conduit 64 is connected to the conduit 63 and the conduit 62 is connected to the conduit 65.
The valve 66 is arranged in such a manner that in normal position the conduit 64 is connected with the conduit 65 while each of the conduits 67 and 68 is closed, and in the emergency position, the conduit 67 is connected with the conduit 64 and the conduit 68 is connected with the conduit 65.
As long as the power plant 18 operates normally, the pilot leaves the valve 66 in normal position, which removes pressure from the circuit 62, 63, 64, 65 of the motor 14a. The system operates in the manner described above with reference to FIG. 1.
If the power plant 18 fails, the pilot places the valve 66 in emergency position and, acting on the tiller, he manually actuates not only the pilot motor 14 of the rudder but due to the movement of valve 61 will also actuate the emergency motor 14a of the rudder 1011 so that the two rudders 10 and 10a are displaced concurrently in the desired direction. It will be noted that while the connecting of the motor 14a will force the helmsman, for one and the same angular displacement of the rudders, to eflect a larger number of turns at the tiller 21, this will have the effect of reducing in the same proportion the unit force which he will have to supply.
Referring to FIG. 3 there is illustratively shown an application of the invention to the hydraulic control of the rudders of a push-pull tugboat having two rudders 10 and 10a and four deflectors 80, 81 and 80a, 81a.
The arrangement shown in FIG. 3 is similar to that which has been described with reference to FIG. 2. The system comprises in addition, the two deflectors 80 and 81 which are arranged opposite the rudder 10 and upstream of a propeller 82 as well as the two deflectors 80a and 81 which are arranged opposite the rudder 10a and upstream of a propeller 82a.
The deflectors 80 and 81 are actuated by a hydraulic motor 83 of any suitable type, for instance the rotary type. To the motor 83 there are connected two conduits 84 and 85 which are connected to a distributor 86 which cooperates, furthermore, with two other conduits 87 and 88.
The distributor 86 is actuated by a rocker lever 110 on which the deflector 80 and the rudder 10 react. For this purpose, the rocker lever 110 is connected to the deflector 80 by a connecting rod 111 and to the rudder 10 by a transmission 89, for instance having a flexible cable including an elastic centering device 90 similar to the device 38.
The valve 86 is actuated in a manner similar to that in which the valve 45 is actuated by the rocker lever 40 so as to occupy either a neutral position or a position in which it connects the conduit 84 with the conduit 87 and the conduit 85 with the conduit 88, or a position in which it connects the conduit 84 with the conduit 88 and the conduit 85 with the conduit 87.
The deflectors a and 81a are provided with an equipment similar to that which has just been described in connection with the deflectors 80 and 81, the parts of said equipment being designated by the same reference numbers followed by the subscript a and comprising a motor 83a, a distributor 86a for the conduits 84a, a, 87a and 88a, a rocker lever a, a connecting rod 111a and a transmission 89a with centering device 90a associated with the rudder 10a.
The conduits 87 and 87a are connected at 91 to the conduit 51 while the conduits 88 and 88a are connected at 94 to the conduit 52.
A hydrovalve is inserted in the conduits 84 and 85 between the motor 83 and the distributor 86 while a hydrovalve 120a is inserted in the conduits 84a and 85a between the motor 83a and the distributor 86a.
The hydrovalves 120 and 120a are controlled automatically by means of conduits 121 and 121a in response to a drop in pressure of the hydraulic power plant 18 so as to block the motors 83 and 83a. Such a drop in pressure has the eflect, due to a conduit 122, of automatically actuating a hydrovalve 66 replacing the manual valve 66 of FIG. 2, to connect the emergency motor 14a to the manual power source 19.
A manual system which makes it possible, if necessary, to disconnect the automatic control, can advantageously be provided.
As many changes could be made in the above constructions, and many apparently widely diiferent embodiments of this invention could be made without departing from the scope of the claims, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.
Having thus described our invention, what we claim as new and desire to secure by Letters Patent of the United States is:
1. A hydraulic control system for a ship comprising a pilot station having a manually operated source of fluid under pressure, a hydraulic power source, a first rudder controlled by the manually operated power source at the pilot station and having two hydraulic motors, one of said motors comprising a pilot motor operatively connected to said manual power source at said pilot station and the other of said motors comprising a main power motor operatively connected to said hydraulic power source, a hydraulically controlled valve between said hydraulic power source and said main motor, said hydraulically controlled valve being operatively connected to said manual power source at said pilot station and controlled thereby, a second rudder having at least one main motor operatively connected to said hydraulic power source, a distributor valve between said hydraulic power source and said second motor and means controlled by the movement of said first rudder to actuate said distributor valve to effect corresponding movement of said second rudder.
2. The combination set forth in claim 1 in which said distributor valve has a control rod, a rocker lever is pivotally connected at its center to said control rod, a pair of links are provided connected respectively between the ends of said rocker lever and an associated rudder, one of said links having a resilient centering device associated therewith to permit extension and contraction of the length of the associated link from its predetermined length and normally urging said link to said predetermined length.
3. The combination set forth in claim 2 in which said centering device comprises a cylindrical casing, the associated link having two portions, the end of one of said portions being rigidly connected to one end of said casing and at its other end to one of said rudders, a stop member slidably mounted in said casing, one end of the other link extending through said casing and being secured to said stop member, the other end of said link being connected to the other rudder and a pair of resilient means in said casing normally compressed between the ends of the casing and said stop member.
4. The combination set forth in claim 1 in which valve means are provided between said second main motor and said hydraulic power source to control the flow of fluid under pressure to said second main motor whereby when said valve means is in closed position, said second main motor will be blocked.
5. The combination set forth in claim 4 in which an electric solenoid actuates said valve means and switch means is provided at said pilot station to control said solenoid.
6. The combination set forth in claim 1 in which an emergency motor is also operatively connected to said second rudder, an emergency valve is connected between said manual power source at said pilot station and said emergency motor, a second distributor valve is connected between said emergency valve and said emergency motor, said second distributor valve having a control rod operatively connected to the control rod of said first distributor valve and actuated by the movement of said first rudder whereby when said emergency valve is opened fluid under pressure will flow from said manual power source at said pilot station through said second distributor valve to said emergency motor for movement of said second rudder.
7. The combination set forth in claim 1 in which a pivotally mounted deflector is associated with each of said rudders and longitudinally spaced therefrom along the length of the ship, a hydraulic motor is operatively connected to each of said deflector members to actuate the latter, an additional distributor valve is associated with each of said motors, means controlled by the movement of the associated rudder to actuate the associated distributor valve to connect the associated motor to the hydraulic pressure source, a hydraulically operated valve connected between each motor and the associated distributor valve, said hydraulically operated valves being controlled by the pressure in said hydraulic pressure source whereby when the pressure in said hydraulic pressure source drops below a predetermined value, the hydraulically controlled valves will cut off flow of fluid to said motors to block the latter.
8. The combination set forth in claim 7 in which an emergency motor is also operatively connected to said second rudder, an emergency hydraulically controlled valve is connected between the emergency motor of said second rudder and the manual power source at said pilot station, said emergency hydraulically controlled valve being connected to said hydraulic power source and controlled by the pressure therein, a second distributor valve is connected between said emergency valve and said emergency motor, said second distributor valve having a control rod operatively connected to the control rod of said first distributor valve and actuated by the movement of said first rudder, whereby when the pressure of said hydraulic power source drops below a predetermined amount the emergency valve will open for flow of fluid under pressure from said manual power source at said pilot station through said second distributor valve to said emergency motor for movement of said second rudder.
References Cited UNITED STATES PATENTS 3,302,604 2/1967 Stuteville 1l4l50 MILTON BUCHLER, Primary Examiner.
ANDREW H. FARRELL, Examiner.
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|U.S. Classification||114/150, 91/523|
|International Classification||B63H25/28, B63H25/06|