EP0035858A2

EP0035858A2 - Ship maneuvering gear

Info

Publication number: EP0035858A2
Application number: EP81300871A
Authority: EP
Inventors: Minoru A. Ishida
Original assignee: Ishikawajima Ship & Chemical Plant Co Ltd
Current assignee: Ishikawajima Ship & Chemical Plant Co Ltd
Priority date: 1980-03-10
Filing date: 1981-03-03
Publication date: 1981-09-16
Also published as: JPS56146493A; EP0035858A3

Abstract

A ship maneuvering gear of a ship having two propellers each of which can be turned about a vertical axis perpendicu- larto a propeller shaft thereof, includes a hand lever (HL) that can be rotated about a vertical axis (Z) and can be inclined relative to the vertical axis (Z), the rotation and the inclination of the hand lever (HL) being separately detected. An arithmetic circuit (MC) calculates a first quantity indicating a turn of the propellers proportional to the rotation of the hand lever (HL), and second quantities indicating turns of the propellers to change the ship speed proportional to the inclination of the hand lever (HL), and produces output signals to control the propellers by adding the first and second quantities.

Description

This invention relates to a ship maneuvering gear, and more particularly to a maneuvering gear of a ship having two or more 360°-turning (also called Z-type) propulsion unit each of which units includes a propeller that can turn about a vertical shaft perpendicular to a propeller shaft thereof, so as to change the direction of propulsive force of the ship at will.
Two maneuvering gears have been used heretofore to control two propellers. However, it has been proposed recently to use one maneuvering gear with one lever or handle to maneuver the two propellers so as to facilitate easy maneuver (for instance, Japanese Patent Publication No. 47,234/76).
In a previously proposed one-lever maneuvering gear, propellers are turned in directions corresponding to a direction given by the lever to cause the ship to move ahead and turn, and the lever is also made to be inclined by a variable extent so that the propellers are turned broadside in proportion to the inclination of the lever, so as to control the speed of the ship.
In the aforesaid one-lever maneuvering gear of the prior art, the direction and the inclination (angle of push or pull down) of the one lever are detected as a vector quantity, and the vector quantity is decomposed into components along two horizontal axes, and instructions as to the directions of the two propellers are produced by complicated mathematical operations based on such components of the vector quantity. Whereby, the direction and the magnitude of the vector sum of the propulsive forces of the two propellers are controlled so as to coincide with the direction and the inclination of the lever.
The one-lever system of the prior art has a shortcoming in that the system requires complicated mathematical operations and a complicated arithmetic circuit is indispensable, because the direction and the inclination of the lever are detected as a composite vector quantity having components along two orthogonal coordinates and instructions as to the turning directions of the two propulsion units can be given only after the complicated mathematical operations based on the aforesaid components along the orthogonal coordinates.
Therefore, an object of the present invention is to obviate the abovementioned shortcoming of the pior art, by providing an improved ship maneuvering gear.
To fulfil the object, in a ship maneuvering gear of the present invention, the rotation and the inclination of one lever are separately detected by synchro motors (with a trademark of SELSYN motor) or potentiometers, and the thus detected rotation and inclination are applied to an arithmetic circuit so as to determine first quantity indicating a turn of two propellers proportionate to the rotation of the lever and second quantities indicating broadside turns of the propellers in proportion to the inclination of the lever for causing a change in the ship speed and to add the first and second quantities to produce an output signal which gives orientations to be assumed by the two propellers.
Thus, another object of the invention is to substantially simplify the arithmetic circuit of the ship maneuvering gear.
For a better understanding of the invention, reference is made to the accompanying drawings, in which:

Fig. 1A is a schematic vertical sectional view of a ship maneuvering gear according to the present invention;
Fig. 1B is an explanatory diagram showing the arrangement of a worm gearing means in the maneuvering gear of Fig. lA;
Fig. 2 is a schematic partial plan view of a ship, showing the disposition of two propellers mounted thereon;
Fig. 3 is a partially cutaway perspective view of an operating board in the maneuvering gear of the invention;
Fig. 4 is an explanatory diagram showing the range in which a hand lever is moved;
Fig. 5 is a block diagram of the electic circuit of the ship maneuvering gear of the invention;
Fig. 6 shows diagrammatic illustrations of the setting process of the ship maneuvering gear of the invention;
Fig. 7 shows a maneuvering schedule of two propellers by the ship maneuvering gear of the invention; and
Figs. 8 and 9 are block diagrams showing two examples of the arithmetic circuit and servo amplifier.

Throughout different views of the drawings, 1 is a prime mover, 2 is a horizontal intermediate shaft, 3 is an upper bevel gear, 4 is a vertical intermediate shaft, 5 is a lower bevel gear, 6 is a propeller shaft, 7_p, 7_s are propellers, 8_p, 8_s are hydraulic motors, 9 is a worm shaft, 10 is a vertical turning shaft, 11 is an operating board, HL is a hand lever, P_X, Py are synchro motors or potentiometers, SR is a slip ring, MC is an arithmetic circuit, A-P, A-S are servo amplifiers, F_p, F_s are feedback detector means, T_p, T_s are s^ynchro transmitters, R , R_s are registers, S/A is a synchro analog converter, COMP is a phase comparator, AD is an adder, DS is a differential synchronizer, and SYR is a synchronous rectifier.
Fig. 1 through Fig. 5 illustrate an embodiment of the ship maneuvering gear according to the present invention as applied a ship with two 360°-turning propulsion (Z-type propulsion) units.
Figs. lA, 1B and 2 show the mechanism of a 360°-turning propulsion unit. Output power from a prime mover 1 is transmitted to a port or starboard propeller 7_p or 7_s through a horizontal intermediate shaft 2, an upper bevel gear 3, a vertical intermediate shaft 4, a lower bevel gear 5, and a propeller shaft 6. A hydraulic motor 8_p or 8_s is connected to a worm shaft 9, so as to turn the propeller 7_p or 7 _s about the axis of a vertical turning shaft 10 by the movement of the worm shaft 9 activated by the hydraulic motor 8_p or 8_s.
Figs. 3 through 5 show the structure and formation of the ship maneuvering gear of the invention. Referring to Fig. 3, an operating board 11 of the maneuvering gear has a hand lever HL. As shown in Fig. 4, the hand lever HL is maneuvering lever which can be inclined relative to a vertical center line 0 up to a certain predetermined angle (up to 35° in the illustrated embodiment) and can be freely rotated about the center line 0 within a circle h defined by a 360° rotation of the upper end H' of the hand lever HL with a 35° inclination. P_x and Py are synchro motors or potentiometers to detect the rotation and inclination of the hand lever HL, and the outputs thereof are applied to an arithmetic circuit MC so as to produce signals to actuate the hydraulic motors 8 p and 8_s through servo amplifiers A-P and A-S. The hydraulic motors 8_p and 8_s turn the propellers 7_p and 7_s respectively, while feedback potentiometers F_p and F_s compares the actual orientations of the propellers 7 p and 7_s against set values determined by the arithmetic circuit MC. Synchro transmitters T_p and T_s transmit signals representing the actual orientations of the propellers 7 p and 7_s to the operating board 11, and registers Rand R including servo receivers indicate the actual orientations of the propellers 7p and 7_s in response to the signals from the synchro transmitters T_p and T_s respectively.
The synchro motor or potentiometer P_X to detect the rotation of the hand lever HL may be disposed above or below the slip ring SR of Fig. 3 in tandem therewith, which slip ring SR is disposed along the vertical central axis Z of Figs. 3 and 4.
With the ship maneuvering gear of the aforesaid formation according to the present invention, the direction of propelling the ship is set by rotating the hand lever HL while the magnitude of the propulsive power or the ship speed is controlled by regulating the inclination of the hand lever HL.
The process of setting the two propellers 7p and 7_s at desired orientations by the one hand lever HL of the maneuvering gear of the invention will be described now by referring to Fig. 6.
In the top view of Fig. 6, if the hand lever HL is rotated to the right or clockwise by an angle 6 and if the hand lever HL is pushed down forward by an inclination 35°, the arithmetic circuit MC gives output signals to turn the two propellers 7 p and 7 _s counterclockwise by an angle -6 (the clockwise direction being assumed to be plus in this case).
Then, if the hand lever HL is pulled up to reduce the ship speed, the starboard propeller 7_s is turned from the position of -8 (position lp of Fig. 6) up to a -90° position (position 2s of Fig. 6), while the port propeller 7p is turned from the position of -θ (position lp of Fig. 6) up to a 90° position (position 2p of Fig. 6). More specifically, the rotating angle 6 of the hand lever HL is detected by the synchro motor or potentiometer P_x of Figs. 3 and 5, and the output signal thereof representing the hand lever rotating angle is applied to the arithmetic circuit MC, while the inclination of the hand lever HL is detected by the synchro motor or potentiometer Py and the output signal thereof representing the hand lever inclination is applied to the arithmetic circuit MC through the slip ring SR. The arithmetic circuit MC of Fig. 5 responds to the aforesaid output signals from the synchro motors or potentiometers P_x and Py in the following manner: namely, the starboard propeller 7_s is turned to the -θ position in response to the rotating angle θ of the hand lever HL, and if the hand lever is pushed down forward by 35° an additional turning angle of 0° is added to the aforesaid -6, while if the hand lever HL is pulled up 35° to the upright position (in line with the Z axis) an additional turning angle of (-90°+θ) is added to the aforesaid angle -θ for the starboard propeller 7_s; and the port propeller 7_p is turned to the -θ position in response to the rotating angle θ of the hand lever HL, and if the hand lever HL is pushed down forward by 35° an additional turning angle of 0° is added to the aforesaid -θ, while if the hand lever HL is pulled up to the upright position an additional turning angle of (+90°+θ) is added to the aforesaid -θ for the port propeller 7_p. Thus, the two propellers 7_s and 7_p are turned to the positions 1_s and 1_p, i.e., in counterclockwise direction by an angle -θ, and if the hand lever HL is then pulled up to the upright position, the starboard propeller 7_s is turned from the position ls to the position 2s whose angular displacement is -θ-90°+θ=-90° relative to the X_s axis while the port propeller 7_p is turned from the position 1_p to the position 2_p whose angular displacement is -θ+90°+θ=+90° relative to the X_p axis. If the hand lever HL is pulled down backward by a maximum limit of 35° from the upright position as shown by the dotted line of the top view of Fig. 6, the propellers 7_s and 7p are turned to positions 3c and 3p of the lower views of Fig. 6. More specifically, such pull down of the hand lever HL is detected as a change in the inclination thereof by the synchro motor or potentiometer Py, and the output signal therefrom representing the maximum pull down is applied to the arithmetic circuit MC, so as to generate a signal for the starboard propeller 7_s to turn by an additional angle of (-90°+θ) and a signal for the port propeller 7_p to turn by an additional angle of (+90°+θ).
The aforesaid output from the arithemetic circuit MC for the pulling up of the hand lever HL from the solid line position of the top view of Fig. 6 to the dotted line position thereof through the upright position fully coincides with that for the clockwise rotation of the hand lever HL from the aforesaid solid line position to the dotted line position with an angular displacement of (180°+θ) along the circular path of the same view. More specifically, when the rotating angle of the hand lever HL becomes (180°+8), which is in the third quadrant in the top view of Fig. 6, the response of the maneuvering gear to the signal from the synchro motor or potentiometer P_x is changed from that for the first quadrant, and the starboard propeller 7_s turns counterclockwise by (-180°+θ) relative to the X _s axis while the port propeller 7 p also turns counterclockwise by (-180°+θ) relative to the X_p axis, which can be reached by clockwise rotation of (180°+θ), so that the aforesaid full coincidence is fulfilled.
In the foregoing, the hand lever HL is rotated from the first quadrant to the third quadrant in the top view of Fig. 6, and the operation of the maneuvering gear is similar to what has been described in the foregoing, even when the hand lever HL is turned from the second quadrant to the fourth quadrant.
If the hand lever HL is rotated counterclockwise into the fourth quadrant at first and then rotated further, the turning direction of the propellers 7 _s and 7_p becomes clockwise, but other operations are similar to what has been described above.
Fig. 7 shows a manuevering schedule of the maneuvering gear of the invention in terms of the relationship among the position of the hand lever HL, orientations of the propellers 7 _s and 7 p as indicated by the registers R_sand R_p (arrows in Fig. 7), and the moving direction of the ship (arrows in Fig. 7). For instance, Operation No. 1 shows that the hand lever HL is held upright with its top H' at the neutral position so as to keep the ship at rest. Operations No. 2 and No. 3 show that the ship moves ahead at full speed and at middle speed and that the orientations of the propellers vary with the ship speed even when the ship moves straightly ahead. Operations No. 4 and No. 5 show that the ship moves ahead, while turning port and starboard and that the two propellers assume identical orientations at full speed but the two propellers assume different positions at middle speed as shown by the dotted lines of Fig. 7. Similarly, the ship can be maneuvered so as to turn starboard and port about one point or to move back simply by setting the hand lever HL accordingly as shown in Fig. 7.
Figs. 8 and 9 show two examples of the arithmetic circuit MC and the servo amplifiers A-P and A-S, in which examples the detecting means P_x and Py are assumed to be synchro motors whose outputs are applied to the arithmetic circuit MC so as to produce signals applicable to the hydraulic motors 8p and 8 _s through the servo amplifiers A-P and A-S.
In the example of Fig. 8, the two output signals from the synchro motors P_x and Py are applied to synchro analog converters S/A of the arithmetic circuit MC for analog conversion. Outputs from the synchro analog converters S/A are applied to and processed by an adder AD, and the output from the adder AD is amplified by an amplifier AMP. The amplified signal from this amplifier AMP is applied to feedback adders FAD to which signals from the feedback potentiometers F_p and F_s for the propellers 7p and 7_s are also applied, so as to effect arithmetic operations necessary for the desired feedback control.
The feedback detector means F and F of this p s examples can be potentiometers.
The output signals from the feedback adders FAD are amplified by amplifying circuits AMP of the servo amplifiers A-P and A-S. In the servo amplifiers A-P and A-S of this example, phase comparators COMP receive the amplified signals from the amplifying circuits AMP thereof and compare the received signals against a reference so as to separate clockwise instruction signals from counterclockwise instruction signals. Each servo amplifier A-P or A-S is connected to two magnetic valves MV, so that the corresponding hydraulic motor 8 p or 8 _s is selectively driven either clockwise or counterclockwise.
In the example of Fig. 9, the signal from each of the synchro motors P_x and Py is applied to both of two differential synchronizers DS of the arithmetic circuit MC respectively. The differential synchronizers DS of this example also receive signals from the feedback synchro motors F_p and F_s for the propellers 7_p and 7_s, so as to effect the arithmetic operations necessary for the desired feedback control. The output signals from the arithmetic circuit MC are applied to the servo amplifiers A-P and A-S, where synchronous rectifiers SYR separate clockwise instruction signals from counterclockwise instruction signals based on the nature of the output signals from the arithmetic circuit MC, e.g., potentials thereof, and the thus separated instruction signals are amplified by amplifier circuits AMP provided for each of the clockwise and counterclockwise instruction signals. Each servo amplifier A-P or A-S is connected to the corresponding hydraulic motor 8p or 8_s through two magnetic valves MV, as in the case of the example of Fig. 8.
As noted above, the example of Fig. 9 uses feedback synchro motors F_p and F instead of the feedback potentiometers F_p and F_s of Fig. 8.
When either one or both of the detecting means P_xand Py are potentiometers, only the example of Fig. 8 can be used, and the operations of the maneuvering gear with such detecting potentiometers are similar to those with the detecting synchro motors as described in the foregoging, except that the synchro analog converters S/A can be dispensed with in the case of detecting potentiometers.
As described in the foregoing, in the ship maneuvering gear of the invention, the hand lever HL can be rotated and inclined to any position in the 360° range, so that the ship can be maneuvered to move not only ahead and back but also sideways, and the composite propulsive power of the two propellers 7_p and 7_s can be varied from zero to the maximum by controlling the inclination of the hand lever HL while maintaining the constant propulsive powers at the individual propellers. Accordingly, the ship speed can be controlled from stop as instructed by the upright or neutral position of the hand lever HL to the full speed as instructed by the maximum inclination of the hand lever HL.
As explained above, the ship manuevering gears of the prior art have shortcomings in the need of complicated arithmetic circuit, the requirement of much man power for manufacture and the high manufacturing cost, but the ship maneuvering gear of the invention uses a very simple arithmetic circuit as compared with that of the prior art, so that the maneuvering gear of the invention can be manufactured easily at a low cost; namely, the mathematic circuit in the invention is simplified by separately detecting the rotation and the inclination of hand lever, determining a first quantity to turn the propellers in response to the detected rotation of the hand lever, determining second quantities to turn the propellers broadside in response to the detected inclination of the hand lever representing a change of ship speed, and summing the first and second quantities in the arithmetic circuit so as to give orientations to be assumed by the two propellers.
Although the invention has been described with a certain degree of particularity, it is understood that the present disclosure has been made only by way of example and that numerous change in details of construction and the combination and arrangement of parts may be resorted to without departing from the scope of the invention as hereinafter claimed.

Claims

1. A maneuvering gear of a ship having two propellers each of which propellers can be turned about a vertical axis perpendicular to a propeller shaft thereof, said maneuvering gear comprising a hand lever adapted to be rotated about an axis by a variable rotating angle and to be inclined relative to said axis by a variable inclination, a detecting means to separately detect the rotating angle and the inclination of said hand lever, an arithmetic circuit adapted to respond to the thus detected rotating angle and inclination of the hand lever so as to determine a first and second quantities and to produce an output signal by adding said first and second quantities, said first quantity indicating a turn of said propellers proportionate to said hand lever rotating angle, said second quantities indicating turns of said propellers to cause a speed change of the ship proportionate to said hand lever inclination, and an actuating mans adapted to control said propellers in response to said output signal from the arithmetic circuit.

2. A maneuvering gear as set forth in claim 1, wherein said detecting means includes a synchro motor responding to said rotating angle of the hand lever and a synchro motor responding to said inclination of the hand lever.

3. A maneuvering gear as set forth in claim 1, wherein said detecting means includes a potentiometer responding to said rotating angle of the hand lever and a potentiometer responding to said inclination of the hand lever.

4. A maneuvering gear as set forth in claim 1, wherein said actuating means includes two hydraulic motors coupled to said propellers through worm gearing means.

5. A maneuvering gear as set forth in claim 1, wherein said maneuvering gear further comprises synchro transmitters producing signals representing orientations of the propellers and registers including synchro receivers to receive said signals from the synchro transmitters so as to indicate the orientations of the propellers.

6. A maneuvering gear as set forth in claim 1, wherein said maneuvering gear includes feedback detector means to detect orientations of said propellers so as to give signals showing such orientations and servo amplifier means to receive signals from said arithmetic circuit so as to deliver amplified signals to said actuating means; said arithmetic circuit includes two synchro analog converters to convert signals from said detecting means, an adder to add converted signals from said synchro analog converters, and feedback adders to receive signals both from said adder and from said feedback detector means so as to produce output signals of the arithmetic circuit; and said servo amplifier means includes amplifier circuits to amplify signals from said arithmetic circuit and comparator means to differentiate clockwise instruction signals to said propellers from counterclockwise instruction signals thereto by comparing signals from said amplifier circuits against a reference.

7. A maneuvering gear as set forth in claim 1, wherein said maneuvering gear includes feedback detector means to detect orientations of said propellers so as to give signals showing such orientations and servo amplifier means to receive signals from said arithmetic circuit so as to deliver amplified signals to said actuating means; said arithmetic circuit includes differential synchronizer means to receive signals both from said detecting means and from said feedback detector means so as to produce output signals of the arithmetic circuit; and said servo amplifier means includes synchronous rectifier means to differentiate clockwise instruction signals to said propellers from counterclockwise instruction signals thereto depending on nature of said output signals of the arithmetic circuit and amplifier circuits to amplify the thus differentiated signals from said synchronous rectifier means.

8. A maneuvering gear as set forth in any one of claims 6 and 7, wherein said feedback detector means are synchro motors coupled to said propellers.

9. A maneuvering gear as set forth in any one of claims 6 and 7, wherein said feedback detector means are potentiometers coupled to said propellers.

-10. A maneuvering gear as set forth in claim 1, wherein said detecting means are potentiometers coupled to said hand lever so as to detect the rotation and inclination of said hand lever, said maneuvering gear further comprising feedback potentiometers to detect orientations of said propellers so as to give signals showing such orientations and servo amplifier means to receive signals from said arithmetic circuit so as to deliver amplified signals to said actuating means; said arithmetic circuit includes an adder to add signals from said potentiometers of said detecting means, and feedback adders to receive signals both from said adder and from said feedback potentiometers so as to produce output signals of the arithmetic circuit; and said servo amplifier means include amplifier circuits to amplify signals from said arithmetic circuit and comparator means to differentiate clockwise instruction signals to said propellers from.counterclockwise instruction signals thereto by comparing signals from said amplifier circuits against a reference.