MARINE STEERING DEVICE FOR SHIPS EQUIPPED WITH TWO PROPELLERS
United States Patent 3636910
A marine steering device for ships equipped with two propellers having at ast one frictional coupling mechanism provided in association with shafts of steering handles for coupling the handles to control the rotation of the two propellers about their vertical shafts to control the ship's heading.
US Patent References:
Driving mechanism for phonographs
Valiquet - September 1924 - 1508827
Means for controlling the power drive in a winding or other machine
Johnstone - May 1940 - 2201233
Power operated window regulator
Lakin - December 1943 - 2337902
Master control assembly for an audio volume control system
Scanlon - August 1966 - 3266326
Friction coupling and brake control apparatus
Ganley - September 1966 - 3275109
Driving mechanism for phonographs
Valiquet - September 1924 - 1508827
Means for controlling the power drive in a winding or other machine
Johnstone - May 1940 - 2201233
Power operated window regulator
Lakin - December 1943 - 2337902
Master control assembly for an audio volume control system
Scanlon - August 1966 - 3266326
Friction coupling and brake control apparatus
Ganley - September 1966 - 3275109
Application Number:
04/876340
Publication Date:
01/25/1972
Filing Date:
11/13/1969
View Patent Images:
Export Citation:
Assignee:
Kabushikikaisha, Tokyo Keiki Seizosho (Tokyo Keiki Seizosho Co., Ltd.)
, (Tokyo, JA)
, (Tokyo, JA)
Primary Class:
Other Classes:
440/63
International Classes:
B63H25/42; B63H25/00; B63H5/12
Field of Search:
115/37,35 114/155,163 74/665LM 192/56 64/3R,3C
US Patent References:
Primary Examiner:
Blix, Trygve M.
Assistant Examiner:
Rutledge, Carl A.
Claims:
I claim as my invention
1. A marine steering device for a vessel with two steerable propellers comprising:
2. A marine steering device for a vessel with two steerable propellers comprising:
1. A marine steering device for a vessel with two steerable propellers comprising:
2. A marine steering device for a vessel with two steerable propellers comprising:
Description:
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a marine steering device, and more particularly to a marine steering device for ships equipped with two propellers.
2. Description of the Prior Art
There has recently been proposed and put into practical use a marine steering system which employs two propellers provided bisymmetrically and is adapted to freely turn the ship's heading by changing the directions of the propellers without using a rudder to enable rapid steerages such as forward, backward, lateral, and oblique movements. However, such a conventional steering device usually employs a changeover device for changing over the propellers for turning the two propellers by the same angle about vertical shafts while holding them in parallel relation for turning the ship's heading during forward or backward movement of the ship, or for separately turning the propellers by desired angles for any other desired steerage. This prior art system is advantageous in that since the steering handles of the two propellers are interlocked with each other, a desired steerage can be achieved with the operation of only either one of the handles, but the system has drawbacks such as necessity of the changeover device of complicated construction and its operation for each changeover action.
SUMMARY OF THE INVENTION
In view of the foregoing, the primary object of this invention is to provide a marine steering device which avoids the aforementioned defects by the employment of a frictional coupling mechanism.
Another object of this invention is to provide a marine steering device which has a frictional coupling mechanism for operating it.
Other objects, features and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic block diagram of a ship equipped with two propellers viewed from its rear side;
FIG. 2 is its side view;
FIG. 3A illustrates a first embodiment of the invention;
FIG. 3B illustrates a second embodiment of the invention;
FIG. 3C is a sectional view of a frictional clutch of the invention;
FIG. 4 is a schematic view of a modification of the invention;
FIG. 5, is a schematic view of a further modification of the invention; and
FIG. 6 is a schematic view of yet another modification of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIGS. 1 and 2 reference numerals 2P and 2S indicate left and right propellers which are respectively mounted to the underside of the stern of a ship 1 by vertical shafts 3P and 3S, which shafts are designed to be rotatable about their center vertical axes (not shown) to allow the direction of thrust from the propellers to be varied. In FIGS. 3 to 6 reference numerals 4P and 4S identify steering handles for controlling the rotation of the vertical shafts 3P and 3S and 5P and 5S respectively designate signal generators or generator units of servosystems for remote control of the rotational angles of the propellers 2P and 2S and receivers connected with the generators 5P and 5S through transmission lines (not shown) are respectively located near the propellers 2P and 2S. The servosystems are usually made up of synchros, potentiometers, or the like and the rotational angles of rotary shafts 6P and 6S of the generators 5P and 5S are transmitted to the receivers to rotate the propellers 2P and 2S by angles which are the same as or proportional to the rotational angles of the rotary shafts 6P and 6S. The steering handles 4P and 4S are respectively affixed to the upper ends of the rotary shafts 6P and 6S.
In FIG. 3A a pair of opposing disks 7P are affixed to the rotary shaft 6P and a gear disk 8P is held between the disks 7P in a frictional engagement relation thereto. Namely, the disks 7P and 8P may be referred to as a frictional engagement mechanism. While, a usual gear 9 is directly affixed to the other rotary shaft 6S. The gears 8P and 9 are interconnected through an intermediate gear 10. The steering handle 4P is connected to rotary shaft 6P which is in turn connected to generator 5P. Handle 4S is connected to vertical shaft 6S which is connected to generator 5S. The gear 9 is fixed to shaft 6S and meshes with the gear 10 which is supported on a suitable supporting shaft. Gear 10 also meshes with gear 8P which is frictionally held by disks 7P mounted on shaft 6P such that gear 8P can slide relative to shaft 6P if the friction of the disks 7P is overcome.
FIG. 3B illustrates a modification of the invention wherein shaft 6P carries a gear 9' which is fixed to it and which meshes with a gear 8 that is frictionally supported by friction disks 7 on a shaft which nonrotatably supports a gear 10. Gear 10 meshes with gear 9 mounted on shaft 6S.
With reference to FIG. 3C, one practical embodiment of the frictional engagement mechanisms of the present invention will hereinbelow be described. The disks 7P consist of disks 7P 1 and 7P 2 formed of a metal such as iron. The one disk, for example, 7P 2 is fixed to the shaft 6P by means of, for example, a pin P 1 and the gear 8P is rotatably mounted on the disk 7P 2 and the other disk 7P 1 is disposed on the gear 8P. Above the disk 7P 1 a spring SP is disposed about the shaft 6P and is fixed at its upper end by a stopper ST to press down the disk 7P 1 . Consequently, the gear 8P is urged into contact with the disks 7P 1 and 7P 2 and is adapted to be rotatable about the shaft 6P. Reference character P 2 indicates a pin by means of which the disk 7P 1 is secured to the shaft 6P so as to prevent it from rotation together with the gear 8P.
If necessary, sheets of a material of a great frictional coefficient such as rubber, Bakelite, or the like may be disposed between the disks 7P and the gear 8P.
Assuming that only the steering handle 4P is rotated, the rotation of the shaft 6P is transmitted to the generator 5P and, at the same time, it is transmitted to the shaft 6S and the handle 4S through the frictional engagement of the disks 7P and 8P and through the gears 10 and 9. In this case, the rotation of the shaft 6S is transmitted to the generator 5S. Consequently, by selecting the number of the teeth of the gears 8P and 9 to be the same, it is possible to turn the rotary shafts of the generators 5P and 5S by the same angle in the same direction with the operation of the handle 4 only. The rotation of the steering handle 4S is also transmitted to the generator 5S and, at the same time, to the shaft 6P and then the generator 5P through the gears 9 and 10, the frictionally coupling gear 8P and the disk 7P. Accordingly, the operation of only either one of the steering handles 4P and 4S leads to automatic operation of the both rotary shafts 6P and 6S to rotate the both generators 5P and 5S together by the same angle in the same direction. This rotation is transmitted respectively to the receivers to drive the propellers 2P and 2S by the same angle in the same direction.
Further, the rotary shafts 6P and 6S are interconnected through the frictionally coupling disk 7P and the gear 8P, so that it is possible to drive the handles 4P and 4S independently of each other. Namely, in the event that the handle, for example, 4P is rotated while maintaining the handle 4S at a standstill, the disks 7P are forced to turn by the handle 4P and the disk gear 8P is forced to be at a standstill through the gears 10 and 9 in the same manner as the shaft 6S. In this case, since the disks 7P and the disk gear 8P are in frictional engagement with each other, they are automatically slipped therebetween to allow the rotation of the one shaft and the stoppage of the other shaft. The rotation of the shaft 6P and the stoppage of the shaft 6S are respectively transmitted to the propellers 2P and 2S through the generators 5P and 5S and their corresponding receivers. Also in the case where the handle 4S is turned differently from the handle 4S, a slip is automatically produced in the frictional coupling mechanism between the discs 7P and the gear 8P in accordance with the difference in rotation between the disks 7P and 8P, permitting the shafts 6P and 6S to smoothly rotate independently of each other. Thus, if the coefficient of friction and consequently the frictional force between the disks 7P and the gear 8P is selected to be suitable, turning of only either one of the handles causes the other handle (shaft) to rotate due to the frictional force precisely following the rotation of the former, so that the two handles (shafts) are rotated together. While, when the two handles are turned independently, the disks 7P and the gear 8P smoothly slips therebetween to allow the both shafts to rotate independently of each other.
In FIG. 3B the frictional engagement mechanism mounted on the shaft 6P in FIG. 3A is affixed to the shaft of the intermediate gear 10 and a gear 9' is mounted on the shaft 6P and meshes with the gear 8 which is in frictional engagement with a pair of opposed disks 7 mounted coaxially with the gear 10. The other elements are the same as those in FIG. 1A.
FiG. 4 illustrates a modified form of this invention in which there are interposed between the shafts 6P and 6S a frictional coupling mechanism similar to that in FIG. 3 and a worm gear mechanism for the one-way transmission of the rotation of the one shaft to the other. Namely, a disk 8'P, which makes frictional contact with the disks 7P affixed to the shaft 6P, takes the form of a worm gear instead of the usual gear 8P depicted in FIG. 3 and a worm 11 meshing with the worm gear 8'P is affixed to a shaft (not shown) perpendicular to the shaft 6P. The gear 9 affixed to the shaft 6S is coupled with the worm 11 through a gear 12 and bevel gears 13 to change the rotational direction of the gear 12 into a vertical direction thereto. The shaft 6S is connected to the handle 4S and carries the gear 9 which is fixed to it. Shaft 6S also drives the generator 5S. The shaft 9 meshes with a gear 12 supported on a shaft which carries one of two bevel gears 13 which mesh together. The second bevel gear is driven by a worm 11 which meshes with worm gear 8'" rotatably supported on shaft 6P by the friction disks 7P. The handle 4P is connected to the shaft 6P.
With the arrangement such as shown in FiG. 4 when the handle 4S is only operated, the rotation of the steering handle 4S is transmitted directly to its receiver 5S through the shaft 6S and, at the same time, to the handle 4P through the gears 9, 12, and 13, the worm 11, the worm gear 8'P, the frictional coupling mechanism 8'P-7P and the shaft 6P, thus transmitting the rotation of the shaft 6P to the other receiver 5P. However, in the event that only the other steering handle 4P is turned, the transmission of the rotation from the worm gear 8'P to the worm 11 is almost impossible due to the gear relationship therebetween and the worm gear 8'P is forced to stop, so that the disks 7P and the worm gear 8'P automatically slip therebetween to allow only the shaft 6P to rotate in accordance with the operation of the handle 4P. Thus, the rotation of the shaft 6P is furnished to the signal generator 5P but is not transmitted to the other generator 5S. Consequently, in the illustrated embodiment only the handle 4S is interlocked with the other handle and shaft, while the handle 4P rotates only its shaft 6P. Further, when the handles 4P and 4S are separately turned in different manners, the shafts 6P and 6S are smoothly driven with the rotation of the handles. In this case, since the disk 8'P is compelled to follow the rotation of the worm 11, a slip is produced in the frictional coupling mechanism 7P-8'P in accordance with a difference in rotation between the shafts 6P and 6S. With the above arrangement, when the course of a ship is to be turned only the handle 4S is operated and in the event that a straight course is difficult to maintain due to a slight unbalance between right and left steerages, only the handle 4P is turned to compensate for the unbalance. Namely, such a purpose can be attained with one steering operation and without any changeover operation.
FIG. 5 shows another modification of this invention which employs one common steering handle 14 in addition to the steering handles 4P and 4S and the shaft 6S is also provided with a frictional coupling mechanism 7S-8S similar to that of the shaft 6P. Namely, a pair of disks 7S are affixed to the shaft 6S and a gear disk 8S is held between the disks 7S in frictional contact therewith and the gear 8S is coupled with the gear 8P through the intermediate gear 10. A gear 16 is affixed to a rotary shaft 15 carrying the common handle 14 and is coupled with the intermediate gear 10 through a gear 17. The handle 4S drives the shaft 6S which drives the friction disks 7S. The gear 8S is frictionally supported by the disks 7S on shaft 6S and meshes with a gear 10. The shaft which carries the gear 10 also carries a gear 17. The gear 17 meshes with a smaller gear 16 which is fixed to a shaft 15 upon which the common handle 14 is mounted. The gear 10 also meshes with a gear 8P which is supported between friction disks 7P which are attached to shaft 6P upon which the handle 4P is mounted.
In FIG. 5, the rotation of the common handle 14 is transmitted to the gear disks 8P and 8S through the shaft 15 and the gears 16, 17, and 10, thereafter being transmitted to the shafts 6P and 6S and then to the generators 5P and 5S through the frictional coupling disks 7P and 7S respectively. Also in the case where either one of the handles 4P and 4S is rotated, the rotation is equally transmitted to the shafts 6P and 6S and then the generators 5P and 5S. Further, it is also possible to rotate the handles 4P and 4S independently to render particular rotation to their respective shafts and generators. In such a case, a slip occurs in the one or the other frictional coupling mechanism in response to a difference in rotation between the handles 4P and 4S. By selecting the teeth number of the gear 16 to be smaller than that of the gear 17, fine control can be achieved with the operation of the common handle 14.
In FIG. 6 there is depicted a further modified form of this invention in which a unidirectional transmission mechanism is interposed between the common steering handle 14 and the intermediate gear 10. Namely, a worm 18 is mounted on the shaft of the gear 17 coupled with the handle 14 through the shaft 15 and the gear 16 and a worm gear 19 meshing with the worm 18 is provided coaxial with the intermediate gear 10. In the present example when only the common handle 14 is operated, its rotation is transmitted equally to the shafts 6P and 6S through the worm 18, the worm gear 19 and the frictional coupling mechanisms. However, when either one of the steering handles 4P and 4S is operated, the rotation of the worm gear 19 is difficult to be transmitted to the worm 18 and the gears 8P, 10, and 8S are all stopped, so that only the shaft and generator associated with the handle operated are rotated. Further, it is possible to operate each of the handles 4P and 4S irrespective of the common handle 14, the other one, or both of them to render particular rotation to the shaft and generator associated with the handle operated. In such a case, a slip is caused in the frictional coupling mechanism associated with the handle being operated or in the other frictional coupling mechanism to provide a smooth operation.
While the shafts 6P and 6S of the handles are shown to be directly coupled with those of the generators 5P and 5S for the sake of brevity, it is a matter of course that mechanical coupling means such as gears may be disposed between them.
The coupling means for the handle shafts 6P and 6S is not limited specifically to gears but may be, for example, a chain and a chain wheel.
Since the present invention does not require any changeover device and changeover operation in the simultaneous and separate steerings of the propellers, the invention provides a marine pilot device which is simple in construction, highly reliable in operation and easy to handle. Further, an additional provision for a unidirectional transmission mechanism enables any desired operation.
It will be apparent that many modifications and variations may be effected without departing from the scope of the novel concepts of this invention.
1. Field of the Invention
This invention relates to a marine steering device, and more particularly to a marine steering device for ships equipped with two propellers.
2. Description of the Prior Art
There has recently been proposed and put into practical use a marine steering system which employs two propellers provided bisymmetrically and is adapted to freely turn the ship's heading by changing the directions of the propellers without using a rudder to enable rapid steerages such as forward, backward, lateral, and oblique movements. However, such a conventional steering device usually employs a changeover device for changing over the propellers for turning the two propellers by the same angle about vertical shafts while holding them in parallel relation for turning the ship's heading during forward or backward movement of the ship, or for separately turning the propellers by desired angles for any other desired steerage. This prior art system is advantageous in that since the steering handles of the two propellers are interlocked with each other, a desired steerage can be achieved with the operation of only either one of the handles, but the system has drawbacks such as necessity of the changeover device of complicated construction and its operation for each changeover action.
SUMMARY OF THE INVENTION
In view of the foregoing, the primary object of this invention is to provide a marine steering device which avoids the aforementioned defects by the employment of a frictional coupling mechanism.
Another object of this invention is to provide a marine steering device which has a frictional coupling mechanism for operating it.
Other objects, features and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic block diagram of a ship equipped with two propellers viewed from its rear side;
FIG. 2 is its side view;
FIG. 3A illustrates a first embodiment of the invention;
FIG. 3B illustrates a second embodiment of the invention;
FIG. 3C is a sectional view of a frictional clutch of the invention;
FIG. 4 is a schematic view of a modification of the invention;
FIG. 5, is a schematic view of a further modification of the invention; and
FIG. 6 is a schematic view of yet another modification of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIGS. 1 and 2 reference numerals 2P and 2S indicate left and right propellers which are respectively mounted to the underside of the stern of a ship 1 by vertical shafts 3P and 3S, which shafts are designed to be rotatable about their center vertical axes (not shown) to allow the direction of thrust from the propellers to be varied. In FIGS. 3 to 6 reference numerals 4P and 4S identify steering handles for controlling the rotation of the vertical shafts 3P and 3S and 5P and 5S respectively designate signal generators or generator units of servosystems for remote control of the rotational angles of the propellers 2P and 2S and receivers connected with the generators 5P and 5S through transmission lines (not shown) are respectively located near the propellers 2P and 2S. The servosystems are usually made up of synchros, potentiometers, or the like and the rotational angles of rotary shafts 6P and 6S of the generators 5P and 5S are transmitted to the receivers to rotate the propellers 2P and 2S by angles which are the same as or proportional to the rotational angles of the rotary shafts 6P and 6S. The steering handles 4P and 4S are respectively affixed to the upper ends of the rotary shafts 6P and 6S.
In FIG. 3A a pair of opposing disks 7P are affixed to the rotary shaft 6P and a gear disk 8P is held between the disks 7P in a frictional engagement relation thereto. Namely, the disks 7P and 8P may be referred to as a frictional engagement mechanism. While, a usual gear 9 is directly affixed to the other rotary shaft 6S. The gears 8P and 9 are interconnected through an intermediate gear 10. The steering handle 4P is connected to rotary shaft 6P which is in turn connected to generator 5P. Handle 4S is connected to vertical shaft 6S which is connected to generator 5S. The gear 9 is fixed to shaft 6S and meshes with the gear 10 which is supported on a suitable supporting shaft. Gear 10 also meshes with gear 8P which is frictionally held by disks 7P mounted on shaft 6P such that gear 8P can slide relative to shaft 6P if the friction of the disks 7P is overcome.
FIG. 3B illustrates a modification of the invention wherein shaft 6P carries a gear 9' which is fixed to it and which meshes with a gear 8 that is frictionally supported by friction disks 7 on a shaft which nonrotatably supports a gear 10. Gear 10 meshes with gear 9 mounted on shaft 6S.
With reference to FIG. 3C, one practical embodiment of the frictional engagement mechanisms of the present invention will hereinbelow be described. The disks 7P consist of disks 7P 1 and 7P 2 formed of a metal such as iron. The one disk, for example, 7P 2 is fixed to the shaft 6P by means of, for example, a pin P 1 and the gear 8P is rotatably mounted on the disk 7P 2 and the other disk 7P 1 is disposed on the gear 8P. Above the disk 7P 1 a spring SP is disposed about the shaft 6P and is fixed at its upper end by a stopper ST to press down the disk 7P 1 . Consequently, the gear 8P is urged into contact with the disks 7P 1 and 7P 2 and is adapted to be rotatable about the shaft 6P. Reference character P 2 indicates a pin by means of which the disk 7P 1 is secured to the shaft 6P so as to prevent it from rotation together with the gear 8P.
If necessary, sheets of a material of a great frictional coefficient such as rubber, Bakelite, or the like may be disposed between the disks 7P and the gear 8P.
Assuming that only the steering handle 4P is rotated, the rotation of the shaft 6P is transmitted to the generator 5P and, at the same time, it is transmitted to the shaft 6S and the handle 4S through the frictional engagement of the disks 7P and 8P and through the gears 10 and 9. In this case, the rotation of the shaft 6S is transmitted to the generator 5S. Consequently, by selecting the number of the teeth of the gears 8P and 9 to be the same, it is possible to turn the rotary shafts of the generators 5P and 5S by the same angle in the same direction with the operation of the handle 4 only. The rotation of the steering handle 4S is also transmitted to the generator 5S and, at the same time, to the shaft 6P and then the generator 5P through the gears 9 and 10, the frictionally coupling gear 8P and the disk 7P. Accordingly, the operation of only either one of the steering handles 4P and 4S leads to automatic operation of the both rotary shafts 6P and 6S to rotate the both generators 5P and 5S together by the same angle in the same direction. This rotation is transmitted respectively to the receivers to drive the propellers 2P and 2S by the same angle in the same direction.
Further, the rotary shafts 6P and 6S are interconnected through the frictionally coupling disk 7P and the gear 8P, so that it is possible to drive the handles 4P and 4S independently of each other. Namely, in the event that the handle, for example, 4P is rotated while maintaining the handle 4S at a standstill, the disks 7P are forced to turn by the handle 4P and the disk gear 8P is forced to be at a standstill through the gears 10 and 9 in the same manner as the shaft 6S. In this case, since the disks 7P and the disk gear 8P are in frictional engagement with each other, they are automatically slipped therebetween to allow the rotation of the one shaft and the stoppage of the other shaft. The rotation of the shaft 6P and the stoppage of the shaft 6S are respectively transmitted to the propellers 2P and 2S through the generators 5P and 5S and their corresponding receivers. Also in the case where the handle 4S is turned differently from the handle 4S, a slip is automatically produced in the frictional coupling mechanism between the discs 7P and the gear 8P in accordance with the difference in rotation between the disks 7P and 8P, permitting the shafts 6P and 6S to smoothly rotate independently of each other. Thus, if the coefficient of friction and consequently the frictional force between the disks 7P and the gear 8P is selected to be suitable, turning of only either one of the handles causes the other handle (shaft) to rotate due to the frictional force precisely following the rotation of the former, so that the two handles (shafts) are rotated together. While, when the two handles are turned independently, the disks 7P and the gear 8P smoothly slips therebetween to allow the both shafts to rotate independently of each other.
In FIG. 3B the frictional engagement mechanism mounted on the shaft 6P in FIG. 3A is affixed to the shaft of the intermediate gear 10 and a gear 9' is mounted on the shaft 6P and meshes with the gear 8 which is in frictional engagement with a pair of opposed disks 7 mounted coaxially with the gear 10. The other elements are the same as those in FIG. 1A.
FiG. 4 illustrates a modified form of this invention in which there are interposed between the shafts 6P and 6S a frictional coupling mechanism similar to that in FIG. 3 and a worm gear mechanism for the one-way transmission of the rotation of the one shaft to the other. Namely, a disk 8'P, which makes frictional contact with the disks 7P affixed to the shaft 6P, takes the form of a worm gear instead of the usual gear 8P depicted in FIG. 3 and a worm 11 meshing with the worm gear 8'P is affixed to a shaft (not shown) perpendicular to the shaft 6P. The gear 9 affixed to the shaft 6S is coupled with the worm 11 through a gear 12 and bevel gears 13 to change the rotational direction of the gear 12 into a vertical direction thereto. The shaft 6S is connected to the handle 4S and carries the gear 9 which is fixed to it. Shaft 6S also drives the generator 5S. The shaft 9 meshes with a gear 12 supported on a shaft which carries one of two bevel gears 13 which mesh together. The second bevel gear is driven by a worm 11 which meshes with worm gear 8'" rotatably supported on shaft 6P by the friction disks 7P. The handle 4P is connected to the shaft 6P.
With the arrangement such as shown in FiG. 4 when the handle 4S is only operated, the rotation of the steering handle 4S is transmitted directly to its receiver 5S through the shaft 6S and, at the same time, to the handle 4P through the gears 9, 12, and 13, the worm 11, the worm gear 8'P, the frictional coupling mechanism 8'P-7P and the shaft 6P, thus transmitting the rotation of the shaft 6P to the other receiver 5P. However, in the event that only the other steering handle 4P is turned, the transmission of the rotation from the worm gear 8'P to the worm 11 is almost impossible due to the gear relationship therebetween and the worm gear 8'P is forced to stop, so that the disks 7P and the worm gear 8'P automatically slip therebetween to allow only the shaft 6P to rotate in accordance with the operation of the handle 4P. Thus, the rotation of the shaft 6P is furnished to the signal generator 5P but is not transmitted to the other generator 5S. Consequently, in the illustrated embodiment only the handle 4S is interlocked with the other handle and shaft, while the handle 4P rotates only its shaft 6P. Further, when the handles 4P and 4S are separately turned in different manners, the shafts 6P and 6S are smoothly driven with the rotation of the handles. In this case, since the disk 8'P is compelled to follow the rotation of the worm 11, a slip is produced in the frictional coupling mechanism 7P-8'P in accordance with a difference in rotation between the shafts 6P and 6S. With the above arrangement, when the course of a ship is to be turned only the handle 4S is operated and in the event that a straight course is difficult to maintain due to a slight unbalance between right and left steerages, only the handle 4P is turned to compensate for the unbalance. Namely, such a purpose can be attained with one steering operation and without any changeover operation.
FIG. 5 shows another modification of this invention which employs one common steering handle 14 in addition to the steering handles 4P and 4S and the shaft 6S is also provided with a frictional coupling mechanism 7S-8S similar to that of the shaft 6P. Namely, a pair of disks 7S are affixed to the shaft 6S and a gear disk 8S is held between the disks 7S in frictional contact therewith and the gear 8S is coupled with the gear 8P through the intermediate gear 10. A gear 16 is affixed to a rotary shaft 15 carrying the common handle 14 and is coupled with the intermediate gear 10 through a gear 17. The handle 4S drives the shaft 6S which drives the friction disks 7S. The gear 8S is frictionally supported by the disks 7S on shaft 6S and meshes with a gear 10. The shaft which carries the gear 10 also carries a gear 17. The gear 17 meshes with a smaller gear 16 which is fixed to a shaft 15 upon which the common handle 14 is mounted. The gear 10 also meshes with a gear 8P which is supported between friction disks 7P which are attached to shaft 6P upon which the handle 4P is mounted.
In FIG. 5, the rotation of the common handle 14 is transmitted to the gear disks 8P and 8S through the shaft 15 and the gears 16, 17, and 10, thereafter being transmitted to the shafts 6P and 6S and then to the generators 5P and 5S through the frictional coupling disks 7P and 7S respectively. Also in the case where either one of the handles 4P and 4S is rotated, the rotation is equally transmitted to the shafts 6P and 6S and then the generators 5P and 5S. Further, it is also possible to rotate the handles 4P and 4S independently to render particular rotation to their respective shafts and generators. In such a case, a slip occurs in the one or the other frictional coupling mechanism in response to a difference in rotation between the handles 4P and 4S. By selecting the teeth number of the gear 16 to be smaller than that of the gear 17, fine control can be achieved with the operation of the common handle 14.
In FIG. 6 there is depicted a further modified form of this invention in which a unidirectional transmission mechanism is interposed between the common steering handle 14 and the intermediate gear 10. Namely, a worm 18 is mounted on the shaft of the gear 17 coupled with the handle 14 through the shaft 15 and the gear 16 and a worm gear 19 meshing with the worm 18 is provided coaxial with the intermediate gear 10. In the present example when only the common handle 14 is operated, its rotation is transmitted equally to the shafts 6P and 6S through the worm 18, the worm gear 19 and the frictional coupling mechanisms. However, when either one of the steering handles 4P and 4S is operated, the rotation of the worm gear 19 is difficult to be transmitted to the worm 18 and the gears 8P, 10, and 8S are all stopped, so that only the shaft and generator associated with the handle operated are rotated. Further, it is possible to operate each of the handles 4P and 4S irrespective of the common handle 14, the other one, or both of them to render particular rotation to the shaft and generator associated with the handle operated. In such a case, a slip is caused in the frictional coupling mechanism associated with the handle being operated or in the other frictional coupling mechanism to provide a smooth operation.
While the shafts 6P and 6S of the handles are shown to be directly coupled with those of the generators 5P and 5S for the sake of brevity, it is a matter of course that mechanical coupling means such as gears may be disposed between them.
The coupling means for the handle shafts 6P and 6S is not limited specifically to gears but may be, for example, a chain and a chain wheel.
Since the present invention does not require any changeover device and changeover operation in the simultaneous and separate steerings of the propellers, the invention provides a marine pilot device which is simple in construction, highly reliable in operation and easy to handle. Further, an additional provision for a unidirectional transmission mechanism enables any desired operation.
It will be apparent that many modifications and variations may be effected without departing from the scope of the novel concepts of this invention.