KR20220145362A - steering system - Google Patents

Abstract

The steering system 1 mounted on a ship contains the hydraulic actuator 2 which rock|fluctuates the rudder plate 11 via the rudder shaft 12 penetrating the ship bottom, and the pump 41 which discharges hydraulic oil. The first operating chamber 22 and the second operating chamber 23 of the hydraulic actuator are connected to the selector valve 3 by a pair of supply/discharge lines 44 and 45, and the selector valve 3 is connected to the pump line 42 ) is connected to the pump 41. The switching valve 3 includes a spool 31 , and the spool 31 is moved by a moving mechanism 5 . The moving mechanism 5 is configured such that the moving speed of the spool 31 is electrically changeable.

Description

steering system

The present invention relates to a steering system mounted on a ship.

BACKGROUND ART Conventionally, a steering system for operating a rudder plate by hydraulic pressure is mounted on a ship. Such a steering system includes a hydraulic actuator that swings the rudder plate through a rudder shaft penetrating the ship plate. The hydraulic actuator includes a first operation chamber and a second operation chamber, and when hydraulic oil is supplied to one of the first operation chamber and the second operation chamber, the rudder plate oscillates in the port direction, and When hydraulic oil is supplied to the other side, the rudder plate is oscillated in the starboard direction.

For example, Patent Document 1 discloses a steering system in which a hydraulic cylinder having a first operating chamber and a second operating chamber formed on both sides of a ram as a hydraulic actuator is employed. In such a steering system, the 1st operation chamber and the 2nd operation chamber of a hydraulic cylinder are connected with the switching valve by a pair of supply/discharge lines. The switching valve is connected to the pump by a pump line and connected to the tank by a tank line. The switching valve blocks a pair of supply/discharge lines in the neutral position, and makes one of the pair of supply/discharge lines communicate with the pump line and the other with the tank line when the rudder plate is oscillated.

More specifically, the switching valve includes a spool, which is driven by a pair of electromagnetic valves. The switching valve is provided with a pair of pilot chambers for applying pilot pressure to both end surfaces of the spool, and each electromagnetic valve switches whether or not to introduce pilot pressure into the corresponding pilot chamber.

Japanese Patent Laid-Open No. 9-76997

However, in the steering system disclosed in Patent Document 1, since the electromagnetic valve is a simple on-off valve, when the electromagnetic coil of the electromagnetic valve is excited, the spool moves instantaneously. Therefore, flexible operation is difficult.

Accordingly, an object of the present invention is to provide a steering system capable of flexible driving.

In order to solve the above problems, the steering system of the present invention is a steering system mounted on a ship, and a hydraulic actuator including a first operation chamber and a second operation chamber for swinging the rudder plate through a rudder shaft penetrating the ship bottom; a pump for discharging hydraulic oil, a switching valve connected to the first operating chamber and the second operating chamber by a pair of supply and discharge lines, and connected to the pump by a pump line, the switching valve including a spool; It is characterized in that it is provided with a moving mechanism configured such that the moving speed of the spool is electrically changeable.

According to the above configuration, since the moving mechanism for moving the spool is configured such that the moving speed of the spool is electrically changeable, flexible operation is possible.

According to the present invention, a steering system capable of flexible driving is provided.

1 is a schematic configuration diagram of a steering system according to a first embodiment of the present invention.
Fig. 2 is a cross-sectional view of the linear mechanism.
Fig. 3 (a) is a diagram showing an example of a steering command, and (b) is a diagram showing a spool position according to a steering command.
[FIG. 4] It is a sectional view of a part of a ship on which the steering system shown in FIG. 1 is mounted.
[FIG. 5] is a schematic configuration diagram of a steering system according to a second embodiment of the present invention.
6 is a schematic configuration diagram of a steering system according to a third embodiment of the present invention.
7 is a schematic configuration diagram of a steering system according to another embodiment.

(Example 1)

In Fig. 1, there is shown a steering system 1A according to a first embodiment of the present invention. This steering system 1A is mounted on a ship, as shown in FIG.

Concretely, the steering system 1A includes the hydraulic actuator 2 which rock|fluctuates the rudder plate 11 via the rudder shaft 12 penetrating the ship bottom 10 in the vertical direction. In this embodiment, the hydraulic actuator 2 oscillates the rudder plate 11 via the rudder shaft 12 as well as the rudder blade 13 disposed in the ship.

As shown in FIG. 1 , the hydraulic actuator 2 includes a first operation chamber 22 and a second operation chamber 23 , and includes a first operation chamber 22 and a second operation chamber 23 . When hydraulic oil is supplied to one side (the second operating chamber 23 in this embodiment), the rudder plate 11 is oscillated in the port direction (right direction in FIG. 1), and the first operating chamber 22 and the second operating chamber When hydraulic oil is supplied to the other side of (23) (the first operating chamber 22 in this embodiment), the rudder plate 11 is oscillated in the starboard direction (left direction in FIG. 1).

In this embodiment, the hydraulic actuator 2 is a hydraulic cylinder in which the first operating chamber 22 and the second operating chamber 23 are formed on both sides of the ram 21 . Therefore, the supply flow rate of hydraulic oil to one of the 1st operation chamber 22 and the 2nd operation chamber 23 and the discharge flow rate of the hydraulic oil from the other are the same.

The ram 21 has a bar shape extending in a direction perpendicular to the axial direction of the rudder shaft 12 . A pin 24 is installed in the center of the ram 21 , and the pin 24 is engaged with the tiller 13 . In more detail, the rudder 13 is provided with the groove|channel which opens in the direction away from the rudder shaft 12, and the pin 24 is inserted into this groove|channel.

Here, the number of the hydraulic actuators 2 does not necessarily need to be one, and two may be sufficient so that the hydraulic cylinder may be mutually parallel with the rudder shaft 12 interposed therebetween. In addition, the hydraulic actuator 2 does not necessarily have to be a hydraulic cylinder in which the first operation chamber 22 and the second operation chamber 23 are formed on both sides of the ram 21 , and the piston is disposed in a tube whose both ends are closed. and may be a single rod hydraulic cylinder from which a rod extends from its piston.

When the hydraulic actuator 2 is a single rod hydraulic cylinder, the inside of the tube is divided into a first operation chamber 22 and a second operation chamber 23 by a piston. In addition, when the hydraulic actuator 2 is a single-rod hydraulic cylinder, the tube is supported so as to be oscillating, and at the same time, the tip of the rod is pin-connected to the tiller 13 .

Further, the hydraulic actuator 2 may be a hydraulic motor in which the first operation chamber 22 and the second operation chamber 23 are partitioned by vanes. In this case, a plurality of first operation chambers 22 and second operation chambers 23 may be provided, respectively. In addition, when the hydraulic actuator 2 is a hydraulic motor, the rotary shaft of the hydraulic motor is connected to the rudder shaft 12 by a connector. On the other hand, even when the hydraulic actuator 2 is a hydraulic motor, the supply flow rate of hydraulic oil to one of the first operation chamber 22 and the second operation chamber 23 and the discharge flow rate of the hydraulic oil from the other are the same.

The first operation chamber 22 and the second operation chamber 23 of the hydraulic actuator 2 are connected to the switching valve 3 by a pair of supply/discharge lines 44 and 45 . The switching valve 3 is connected to a discharge port of a pump 41 that discharges hydraulic oil by a pump line 42 . In this embodiment, the switching valve 3 is connected to the suction port of the pump 41 by a recovery line 43 .

However, although not shown, the switching valve 3 may be connected to the tank by a tank line. In this case, the suction port of the pump 41 is also connected to the tank by a suction line. Here, this configuration is further employed when the hydraulic actuator 2 is a single rod hydraulic cylinder as described above.

In this embodiment, the pump 41 is a fixed displacement pump. The pump 41 is driven at a constant rotation speed by an electric motor (not shown). However, the rotation speed of the pump 41 is not necessarily constant, and may be changed. In addition, the pump 41 is not necessarily a fixed displacement pump, for example, a variable displacement pump (for example, a swash plate pump or a bent shaft pump) whose inclination angle can be changed may be sufficient.

As shown in Figs. 1 and 2, the switching valve 3 is. It includes a housing (32) and a spool (31) slidably held in the housing (32). When the spool 31 is positioned in the neutral position, the switching valve 3 blocks the supply and discharge lines 44 , 45 , and at the same time makes the pump line 42 communicate with the return line 43 . On the other hand, when the spool 31 moves from the neutral position to one or the other in the axial direction, the selector valve 3 communicates one of the supply/discharge lines 44 and 45 with the pump line 42 and connects the other with the recovery line. (43) is communicated.

The spool 31 is moved by a moving mechanism 5 . The moving mechanism 5 is configured such that the moving speed of the spool 31 is electrically changeable. The moving mechanism 5 is controlled by a control device 6 .

In this embodiment, the moving mechanism 5 is a linear mechanism 5A. Specifically, the linear mechanism 5A includes a rod-shaped connecting member 51 extending in the axial direction of the spool 31 , a nut 52 connected to the spool 31 via the connecting member 51 , and a nut A screw shaft 53 screwed to the 52 and an electric motor 54 for rotating the screw shaft 53 are included. The connecting member 51 , the nut 52 , the screw shaft 53 , and the electric motor 54 are disposed coaxially with the spool 31 . In addition, a cylindrical casing 55 is interposed between the housing 32 and the electric motor 54 , and the connecting member 51 , the nut 52 and the screw shaft 53 are accommodated in the casing 55 . has been

For example, the electric motor 54 is a servo motor. When the electric motor 54 rotates the screw shaft 53 in one direction, the nut 52, the connecting member 51, and the spool 31 move in one of the axial directions of the spool 31, and the electric motor 54 ) rotates the screw shaft 53 in the reverse direction, the nut 52 , the connecting member 51 , and the spool 31 move to the other side in the axial direction of the spool 31 .

Hereinafter, with reference to FIG. 2, the structure of 5 A of linear motion mechanisms is demonstrated in detail. Hereinafter, for convenience of explanation, one (right side in FIG. 2) of the spool 31 in the axial direction is referred to as a right side, and the other (left side in FIG. 2) is referred to as a left side.

In this embodiment, the right end of the spool 31 and the left end of the connecting member 51 are connected by a ball joint. Specifically, a groove 51a is provided at the left end of the connecting member 51, and the ball 35 is held in the groove 51a. On the other hand, at the right end of the spool 31, a plate-shaped projection 31a inserted into the groove 51a is provided, and a hole for fitting with the ball 35 is provided in the projection 31a.

However, contrary to this embodiment, a groove 51a for holding the ball 35 is provided at the right end of the spool 31, and a projection (51a) inserted into the groove 51a at the left end of the connecting member 51 31a) may be installed. Alternatively, the right end of the spool 31 and the left end of the connecting member 51 may be connected by a joint other than a ball joint.

A hole 51b that opens to the right is provided on the center line of the connecting member 51 , and the nut 52 is fixed to the connecting member 51 while being inserted into the hole 51b. Here, the connecting member 51 is guided by a guide mechanism (not shown) so that it can be moved only in the left-right direction (that is, rotation is prohibited).

Furthermore, in this embodiment, between the connecting member 51 and the casing 55, a mechanism for holding the spool 31 in the neutral position when no electric power is supplied to the electric motor 54 is provided. This mechanism includes a coil spring 56 inserted into the connecting member 51 and a pair of spring receivers 57 and 58 for supporting both ends of the coil spring 56 .

The coil spring 56 applies an elastic force for maintaining the spool 31 in the neutral position to the spool 31 via the connecting member 51 . Each of the spring receivers 57 and 58 has a ring shape, and is slidably fitted with the connecting member 51 .

A flange 51c for contact with the spring receiver 58 is provided at the right end of the connecting member 51 . In addition, a stopper 59 for contact with the spring receiver 57 is attached to the connecting member 51 at a position spaced from the flange 51c to the left.

Further, on the inner surface of the casing 55 , a step portion 55b is provided at a position corresponding to the flange 51c , and a step portion 55a is provided at a position corresponding to the stopper 59 .

With this structure, when electric power is not supplied to the electric motor 54, the spring receiver 58 abuts against both the flange 51c and the stepped portion 55b by the elastic force of the coil spring 56, The spring receiver 57 abuts against both the stopper 59 and the step portion 55a. Accordingly, the spool 31 is held in the neutral position.

When the connecting member 51 moves to the left from the state in which the spool 31 is positioned in the neutral position, the spring receiver 58 is pressed against the flange 51c to separate from the step portion 55b, and the stopper 59 ) is spaced apart from the spring bearing (57). Conversely, when the connecting member 51 is moved to the right from the state in which the spool 31 is positioned in the neutral position, the flange 51c is spaced apart from the spring receiver 58, and the spring receiver 57 is moved to the stopper 59. is pushed and spaced apart from the step portion 55a.

However, the coil spring 56 that provides the spool 31 with an elastic force for holding the spool 31 in the neutral position may be provided on the opposite side to the direct acting mechanism 5A with the spool 31 interposed therebetween.

Next, the control performed by the control device 6 will be described in detail. The control device 6 is, for example, a computer including a memory such as a ROM or RAM, a storage such as an HDD or an SSD, and a CPU, and a program stored in the ROM or the storage is executed by the CPU.

A steering command is input to the control device 6 as shown in Fig. 3A. The steering command is a port steering command for rocking the rudder board 11 in the port direction, a stop steering command for stopping the rudder board 11 , and a starboard steering command for rocking the rudder board 11 in the starboard direction. However, the steering command does not necessarily have to be these three, and may include these intermediate steering commands. That is, the waveform of the steering command does not necessarily have to be a rectangular pulse shape, and may be a smooth curve.

When the control device 6 receives a port steering command, that is, when the steering command changes from a stop steering command to a port steering command, the control device 6 moves the spool 31 as shown in Fig. 3(b). The linear mechanism 5A is controlled so that speed may transition on the curve C1. Thereby, the spool 31 moves from the neutral position to the largest opening position where the opening area between the pump line 42 and the supply/discharge line 45 becomes the largest. The curve C1 is an S-curve that gradually decreases after the moving speed of the spool 31 gradually increases.

After that, when the steering command is changed from the port steering command to the stop steering command, the control device 6 controls the linear motion mechanism 5A so that the moving speed of the spool 31 transitions on the curve C2. do. Accordingly, the spool 31 moves from the maximum opening position to the neutral position. The curve C2 is an S-curve that gradually decreases after the moving speed of the spool 31 gradually increases.

Conversely, when the control device 6 receives the starboard steering command, that is, when the steering command changes from the stop steering command to the starboard steering command, the moving speed of the spool 31 changes on the curve C3. 5A of the linear motion mechanism is controlled so that it may do so. Accordingly, the spool 31 moves from the neutral position to the maximum opening position where the opening area between the pump line 42 and the supply/discharge line 44 becomes the maximum. The curve C3 is an S-curve that gradually decreases after the moving speed of the spool 31 gradually increases.

After that, when the steering command is changed from the starboard steering command to the stop steering command, the control device 6 controls the linear motion mechanism 5A so that the moving speed of the spool 31 transitions on the curve C4. do. Accordingly, the spool 31 moves from the maximum opening position to the neutral position. The curve C4 is an S-curve that gradually decreases after the moving speed of the spool 31 gradually increases.

Further, the control device 6 is electrically connected to a position detector 7 that detects the position of the spool 31 . In the present embodiment, the position detector 7 is a rotary encoder 7A that detects the rotation amount of the electric motor 54 as the position of the spool 31 .

Then, when the control device 6 receives a port steering command or a starboard steering command, the position of the spool 31 detected by the position detector 7 (in this embodiment, it is detected by the rotary encoder 7A) based on the amount of rotation of the electric motor 54) and the electric current of the electric motor 54, it is determined whether or not the spool 31 is sticked. Accordingly, the stick of the spool 31 can be detected without using a special sensor. This is because the rotary encoder 7A is normally used for the linear mechanism 5A for controlling the electric motor 54 .

In the normal state in which the spool 31 is not stuck, a current corresponding to the thrust required for the spool 31 to move to the target position flows through the electric motor 54 . On the other hand, when the stick occurs, since the spool 31 does not reach the target position, the control device 6 maximizes the current flowing through the electric motor 54 to bring the spool 31 to the target position (that is, , the current value is stuck at the limit). Therefore, if the position of the spool 31 does not change, and the electric motor 54 current value crosses into the limit for about 1 second, the control device 6 determines that the spool 31 is stuck. On the other hand, if the above condition is not satisfied, the control device 6 determines that the spool 31 is not stuck.

When determining that the spool 31 is stuck, the control device 6 may output an error signal. For example, the control device 6 may output an error signal to a display device (not shown) arranged in a shipbuilding room, and display that the spool 31 is stuck on the screen of the display device. . Accordingly, it is possible to notify the shipbuilder that the spool 31 is stuck.

Alternatively, when the control device 6 determines that the spool 31 is stuck, when the control device 6 receives a port steering command, the spool 31 moves in a direction corresponding to the starboard steering command. After moving in the direction corresponding to the port steering command, when the control device 6 receives the starboard steering command, the spool 31 responds to the starboard steering command after moving in the direction corresponding to the port steering command. You may control the linear motion mechanism 5A so that it may move in the direction to When this control is performed, the stick of the spool 31 can be released. On the other hand, the movement in the reverse direction and movement in the normal direction may be performed a plurality of times so that the spool 31 vibrates.

As described above, in the steering system 1A of the present embodiment, since the moving mechanism 5 for moving the spool 31 is configured such that the moving speed of the spool 31 is electrically changeable, flexible operation is possible. do.

However, when the spool 31 is momentarily moved by the excitation of the electromagnetic coil of the electromagnetic valve as in the conventional steering system, a sudden change occurs in the motion of the rudder shaft 12 or the rudder plate 11, and a large impact occurs. Occurs. On the other hand, as in the present embodiment, if the moving speed of the spool 31 gradually increases and then moves on the gradually decreasing curve C1 or C3, this impact can be alleviated.

On the other hand, the control device 6 calculates the supply flow rate of the hydraulic oil to the first operating chamber 22 or the second operating chamber 23 based on the position of the spool 31 detected by the position detector 7 , , you may calculate the angle of the rudder plate 11 based on the calculated supply flow rate. Thereby, the angle of the rudder plate 11 can be grasped|ascertained without using an angle sensor. For example, the control device 6 integrates the calculated supply flow rate to calculate the total supply amount of hydraulic oil to the first operation chamber 22 or the second operation chamber 23 , and from this total supply amount, the rudder plate ( 11) may be calculated.

Furthermore, the control apparatus 6 may output an error signal, when the angle of the calculated rudder board 11 is outside an allowable range. For example, the control device 6 may output an error signal to a display device (not shown) disposed in the shipbuilding room, and display on the screen of the display device that the rudder plate did not swing as steered. Accordingly, it is possible to notify the shipbuilder that the rudder plate 11 is not swinging as it has been manipulated.

The said allowable range is computable from target rudder angle, for example. The target rudder angle is computable from the time during which the control device 6 has received the port direction operation command or the starboard direction operation command. For example, the lower limit of the allowable range may be calculated by subtracting a predetermined value from the target steering angle, or may be calculated by multiplying the target steering angle by a predetermined ratio (eg, 50 to 90%). The upper limit of the allowable range may be calculated by adding all the predetermined values to the target steering angle, or may be calculated by multiplying the target steering angle by a predetermined ratio (eg, 110 to 150%).

(Second embodiment)

Fig. 5 shows a steering system 1B according to a second embodiment of the present invention. On the other hand, in the present embodiment and the third embodiment to be described later, the same components as in the first embodiment are given the same reference numerals, and overlapping descriptions are omitted.

In the present embodiment, a pressure sensor 8 for detecting the pressure in the second operation chamber 23 is installed in the supply/discharge line 45 leading to the second operation chamber 23 . However, the pressure sensor 8 may be provided in the second operation chamber 23 . Alternatively, the pressure sensor 8 may be installed in the first operation chamber 22 or the supply/discharge line 44 to detect the pressure in the first operation chamber 22 .

As in the first embodiment, when the control device 6 receives a port steering command or a starboard steering command, the moving speed of the spool 31 is adjusted to the curve C1 or curve (C1) shown in Fig. 3(b). C3) The linear motion mechanism 5A is controlled so that the phase may change. Furthermore, in this embodiment, the control device 6 corrects the curves C1 and C3 in accordance with the pressure detected by the pressure sensor 8 .

For example, the control device 6 increases the slope of the curves C1 and C3 (a steep slope) when the pressure detected by the pressure sensor 8 is lower than a prescribed value, and conversely, when the pressure is high, the curve C1 , C3) is made small (gentle). Thereby, the fluctuation range of the flow velocity of hydraulic oil resulting from a pressure fluctuation can be suppressed small.

In the steering system 1B of this embodiment, since the curves C1 and C3 are corrected according to the pressure, the position of the spool 31 and the switching valve 3 pass through the curves C1 and C3 compared to the case where the curves C1 and C3 are constant. It is possible to further stabilize the relationship with the flow rate of the working oil.

On the other hand, even if the control device 6 corrects the curves C2 and C4 shown in Fig. 3(b) according to the pressure detected by the pressure sensor 8 when stopping the shaking of the rudder plate 11, good night.

(Example 3)

6 shows a steering system 1C according to a third embodiment of the present invention. 1C of such a steering system, the 1st circuit which consists of the pump 41, the pump line 42, the return line 43, the switching valve 3, and the supply/discharge lines 44 and 45 demonstrated in 1st Embodiment and at the same time further including a second circuit configured similarly to the first circuit.

That is, in the present embodiment, the pump 41, the switching valve 3, the moving mechanism 5, the position detector 7 and the control device 6 described in the first embodiment are the first pump 41, The first switching valve 3 , the first moving mechanism 5 , the first position detector 7 , and the first control device 6 . Further, in the present embodiment, the housing 32 and the spool 31 of the switching valve 3 described in the first embodiment are the first housing 32 and the first spool 31, respectively.

The second circuit, like the first circuit, includes a second pump 41', a pump line 42', a return line 43', a second selector valve 3', and a pair of supply and discharge lines 44'. , 45'). The second selector valve 3' is connected to the first operation chamber 22 and the second operation chamber 23 of the hydraulic actuator 2 by supply/discharge lines 44' and 45'. Further, the second selector valve 3' is connected to the second pump 41' by a pump line 42' and a return line 43'.

Like the first pump 41 , the second pump 41 ′ is a fixed displacement pump, and is driven at a constant rotation speed by an electric motor (not shown). Here, the modified example of the first pump 41 described in the first embodiment is also applicable to the second pump 41'.

The second selector valve 3', similarly to the first selector valve 3, includes a second housing 32' and a second spool 31' slidably held by the second housing 32'. include The second spool 31' is moved by the second moving mechanism 5'.

The 2nd moving mechanism 5' is comprised so that the moving speed of the 2nd spool 31' can be electrically changed similarly to the 1st moving mechanism 5. The second movement mechanism 5 ′ is controlled by a control device 6 . In the present embodiment, the second movement mechanism 5' is a linear mechanism 5A similar to the first movement mechanism 5 .

The second control device 6' is electrically connected to a second position detector 7' that detects the position of the second spool 31'. In the present embodiment, the second position detector 7', similarly to the first position detector 7, determines the rotation amount of the electric motor 54 of the linear mechanism 5A as the position of the second spool 31'. It is a rotary encoder 7A that detects.

The second control device 6 ′ is configured similarly to the first control device 6 . Also, the second control device 6 ′ is capable of communicating with the first control device 6 .

In the present embodiment, the first control device 6 or the second control device 6' determines the position of the first spool 31 detected by the first position detector 7 (in this embodiment, the rotary encoder). Rotation amount of the electric motor 54 of the linear mechanism 5A which is the 1st moving mechanism 5 detected by 7A, and the 2nd spool 31' detected by the 2nd position detector 7' When a mismatch occurs in the positional relationship between the positions of (in this embodiment, the rotation amount of the electric motor 54 of the linear mechanism 5A which is the second moving mechanism 5' detected by the rotary encoder 7A) A signal is output. Accordingly, it can be detected that the first spool 31 of the first selector valve 3 and the second spool 31' of the second selector valve 3' operate differently from each other.

For example, the first control device 6 or the second control device 6 ′ outputs an error signal to a display device (not shown) disposed in the shipbuilding room, and displays the first switching valve 3 on the screen of the display device. It may be indicated that the first spool 31 of , and the second spool 31' of the second selector valve 3' are operating differently.

Examples of the mismatch in the positional relationship between the position of the first spool 31 and the position of the second spool 31' include the case where the position of the first spool 31 and the position of the second spool 31' are different. , the first spool 31 and the second spool 31' may move in opposite directions to each other. In particular, when an error signal is output when the first spool 31 and the second spool 31 ′ move in opposite directions to each other, the first moving mechanism 5 and the second moving mechanism 5 ′ operate the control device ( It can be detected that another command is being received from 6).

Therefore, the first control device 6 or the second control device 6 ′ is the first spool 31 and the second spool 31 ′, when the position of the first spool 31 is different from that of the second spool 31 . When the moving direction and the moving direction of the second spool 31' are different (including a case where one moves and the other does not), the position of the first spool 31 and the position of the second spool 31' It is determined that a mismatch has occurred in the positional relationship between the two.

However, when the steering command received by the 1st control device 6 and the steering command received by the 2nd control device 6' differ from the 1st control device 6 or the 2nd control device 6', an error signal may be printed out. According to this configuration, a malfunction of the first spool 31 or the second spool 31' can be prevented.

On the other hand, the control device 6 may perform the same control as that of the first and second embodiments for the first circuit. Further, the control device 6 may perform the same control as in the first and second embodiments for the second circuit.

(Other Examples)

The present invention is not limited to the above-described embodiments, and various modifications may be made without departing from the gist of the present invention.

For example, the moving mechanism 5 in the first to third embodiments (as well as the second moving mechanism 5' in the third embodiment) does not necessarily have to be a linear mechanism 5A, and is shown in FIG. 7 . A pair of electromagnetic proportional valves 61 and 62 may be used as in the steering system 1D of the modified example. In this case, a pair of pilot chambers 33 and 34 are formed in the switching valve 3 , and electromagnetic proportional valves 61 and 62 are connected to these pilot chambers 33 and 34 . The electromagnetic proportional valves 61 , 62 are connected to the sub-pump 64 by a primary pressure line 63 .

A command current is supplied from the control device 6 to the electromagnetic proportional valves 61 and 66 . The electromagnetic proportional valves 61 and 62 output the secondary pressure corresponding to the command current to the pilot chambers 33 and 34, respectively. In the illustrated example, the electromagnetic proportional valves 61 and 62 are of a direct proportional type in which the command current and the secondary pressure are positively (+), but the electromagnetic proportional valves 61 and 62 are negative (-) of the command current and the secondary pressure. ) may be of the inverse proportional form indicating the correlation of

As shown in Fig. 7, when the moving mechanism 5 is a pair of electromagnetic proportional valves 61 and 62, as a position detector 7 for detecting the position of the spool 31, for example, a stroke sensor ( 7B) or the like needs to be provided in the switching valve 3 . On the other hand, if the moving mechanism 5 is a linear mechanism 5A and the position detector 7 is a rotary encoder 7A that detects the rotation amount of the electric motor 54 included in the linear mechanism 5A, the switching valve ( 3) No need to install a sensor.

(organize)

The steering system of the present invention is a steering system mounted on a ship, and includes: a hydraulic actuator for oscillating a rudder plate through a rudder shaft penetrating a ship bottom and including a first operation chamber and a second operation chamber; and a pump for discharging hydraulic oil; A switching valve connected to the first operating chamber and the second operating chamber by a pair of supply and discharge lines and connected to the pump by a pump line, the switching valve including a spool, moves the spool, and moves the spool and a movement mechanism configured to be electrically changeable in speed.

According to the above configuration, since the moving mechanism for moving the spool is configured such that the moving speed of the spool is electrically changeable, flexible operation is possible.

The steering system includes a control device for controlling the movement mechanism, and the control device, when receiving a steering command for oscillating the rudder plate, causes the spool to move on a gradually decreasing curve after the moving speed gradually increases. The moving mechanism may be controlled. When the spool is momentarily moved by the excitation of the electromagnetic coil of the electromagnetic valve as in the conventional steering system, a sudden change occurs in the motion of the rudder shaft or the rudder plate, resulting in a large impact. On the other hand, as in the above configuration, if the moving speed of the spool gradually increases and then moves on a gradually decreasing curve, such an impact can be alleviated.

The steering system may include a pressure sensor for detecting a pressure in the first operating chamber or the second operating chamber, and the control device may correct the curve according to the pressure detected by the pressure sensor. According to this structure, compared with the case where a curve is constant, the relationship between the position of a spool and the flow velocity of the hydraulic oil which passes through a switching valve can be stabilized more.

For example, the said steering system may be provided with the control apparatus which controls the said moving mechanism, and the position detector which detects the position of the said spool.

The moving mechanism is a linear mechanism including a nut connected to the spool, a screw shaft screwed with the nut, and an electric motor rotating the screw shaft, and the position detector is a rotation of the electric motor as a position of the spool. A rotary encoder that detects the whole quantity may be used. When the moving mechanism is a pair of electromagnetic proportional valves, it is necessary to provide, for example, a stroke sensor or the like in the switching valve as a position detector for detecting the position of the spool. On the other hand, if the movement mechanism is a linear mechanism and the position detector is a rotary encoder that detects the rotation amount of the electric motor included in the linear mechanism, there is no need to provide a sensor in the switching valve.

The control device may determine whether or not the spool is stuck based on the detected position of the spool and the current of the electric motor, when receiving a steering command for rocking the rudder plate. According to this configuration, the stick of the spool can be detected without using a special sensor.

The control device may output an error signal when determining that the spool is stuck. According to this configuration, it is possible to notify the shipbuilder that the spool is stuck.

When it is determined that the spool is stuck, the control device may control the moving mechanism to move in a direction corresponding to the steering command after the spool moves in a direction opposite to that corresponding to the steering command. According to this configuration, the stick of the spool can be released.

The control device may calculate a supply flow rate of hydraulic oil to the first operating chamber or the second operating chamber based on the detected position of the spool, and calculate the angle of the rudder plate based on the calculated supply flow rate. . According to such a structure, the angle of a rudder board can be grasped|ascertained without using an angle sensor.

The control device may output an error signal when the calculated angle of the rudder plate is outside the allowable range. According to this configuration, it is possible to notify the shipbuilder that the steering wheel is not oscillating as it is steered.

wherein the pump is a first pump, the spool is a first spool, the selector valve is a first selector valve, the moving mechanism is a first moving mechanism, the position detector is a first position detector, the control device is a first control device, , a second pump for discharging hydraulic oil, connected to the first and second operating chambers by a pair of supply and discharge lines, and connected to the second pump by a pump line, including a second spool A second switching valve, a second movement mechanism configured to move the second spool so that the movement speed of the second spool is electrically changeable, and a second movement mechanism that controls the second movement mechanism and communicates with the first control device a second possible control device and a second position detector for detecting a position of the second spool, wherein the first control device or the second control device is configured to determine the position of the first spool detected by the first position detector. When a mismatch occurs in the positional relationship between the position and the position of the second spool detected by the second position detector, an error signal may be output. According to such a structure, it can detect that the 1st spool of a 1st selector valve and the 2nd spool of a 2nd selector valve are mutually act|operating differently.

The said pump is a 1st pump, the said spool is a 1st spool, the said selector valve is a 1st selector valve, and the said moving mechanism is a 1st moving mechanism, The 1st control apparatus which controls the said 1st moving mechanism, and hydraulic oil are discharged and a second selector valve connected to the first operation chamber and the second operation chamber by a pair of supply and discharge lines, and connected to the second pump by a pump line, and including a second spool. and a second moving mechanism configured to move the second spool so that the moving speed of the second spool is electrically changeable, and a second control configured to control the second moving mechanism and communicate with the first control device A device may be provided, and the first control device or the second control device may output an error signal when the steering command received by the first control device is different from the steering command received by the second control device. According to this configuration, it is possible to prevent malfunction of the first spool or the second spool.

For example, the switching valve may be connected to the pump by a return line.

1A to 1D: steering system
10: bottom
11: Tapan
2: hydraulic actuator
22: first operating room
23: second operating room
33: switching valve
31: spool (first spool)
31': second spool
41: pump (first pump)
41': second pump
42, 42': pump line
43, 43': recovery line
44, 45, 44', 45': delivery line
5: Movement mechanism (first movement mechanism)
5': second moving mechanism
5A: linear mechanism
52: nut
53: screw shaft
54: electric motor
6: control device (first control device)
6': second control device
7: position detector (first position detector)
7': second position detector
7A: Rotary Encoder
8: pressure sensor

Claims (13)

A steering system mounted on a ship, comprising:
A hydraulic actuator comprising a first operation chamber and a second operation chamber for swinging the rudder plate through the rudder shaft penetrating the ship bottom;
a pump for discharging hydraulic oil;
a switching valve including a spool connected to the first operating chamber and the second operating chamber by a pair of supply/discharge lines and connected to the pump by a pump line;
and a moving mechanism configured to move the spool, the moving speed of the spool being electrically changeable. According to claim 1,
a control device for controlling the moving mechanism;
The steering system, characterized in that when the control device receives a steering command for oscillating the rudder plate, the movement mechanism is controlled such that the movement speed of the spool gradually increases and then transitions on a gradually decreasing curve. 3. The method of claim 2,
a pressure sensor for detecting the pressure in the first operating chamber or the second operating chamber;
and the control device corrects the curve according to the pressure detected by the pressure sensor. 4. The method according to any one of claims 1 to 3,
a control device for controlling the moving mechanism;
and a position detector for detecting the position of the spool. 5. The method of claim 4,
The moving mechanism is a linear mechanism including a nut connected to the spool, a screw shaft screwed with the nut, and an electric motor for rotating the screw shaft,
The said position detector is a rotary encoder which detects the rotation amount of the said electric motor as a position of the said spool, The steering system characterized by the above-mentioned. 6. The method of claim 5,
The said control apparatus determines whether the said spool is sticked based on the detected position of the said spool, and the electric current of the said electric motor, when receiving the steering command which rock|fluctuates the said rudder board, The steering system characterized by the above-mentioned. 7. The method of claim 6,
The control device outputs an error signal when it is determined that the spool is stuck. 8. The method of claim 6 or 7,
The control device, when it is determined that the spool is stuck, controls the moving mechanism to move in a direction corresponding to the steering command after the spool moves in a direction opposite to that corresponding to the steering command. steering system. 9. The method according to any one of claims 4 to 8,
The control device calculates a supply flow rate of the hydraulic oil to the first operating chamber or the second operating chamber based on the detected position of the spool, and calculates the angle of the rudder plate based on the calculated supply flow rate. steering system with 10. The method of claim 9,
The control device, when the calculated angle of the rudder plate is outside the allowable range, the steering system, characterized in that outputting an error signal. 11. The method according to any one of claims 4 to 10,
wherein the pump is a first pump, the spool is a first spool, the selector valve is a first selector valve, the moving mechanism is a first moving mechanism, the position detector is a first position detector, the control device is a first control device, ,
a second pump for discharging hydraulic oil;
a second switching valve including a second spool connected to the first operating chamber and the second operating chamber by a pair of supply/discharge lines and connected to the second pump by a pump line;
a second moving mechanism configured to move the second spool, the moving speed of the second spool being electrically changeable;
a second control device that controls the second movement mechanism and is capable of communicating with the first control device;
a second position detector for detecting the position of the second spool;
The first control device or the second control device has a positional relationship between the position of the first spool detected by the first position detector and the position of the second spool detected by the second position detector. When an error occurs, the steering system characterized in that it outputs an error signal. 12. The method according to any one of claims 1 to 11,
the pump is a first pump, the spool is a first spool, the selector valve is a first selector valve, and the moving mechanism is a first moving mechanism;
a first control device for controlling the first moving mechanism;
a second pump for discharging hydraulic oil;
a second switching valve including a second spool connected to the first operating chamber and the second operating chamber by a pair of supply/discharge lines and connected to the second pump by a pump line;
a second moving mechanism configured to move the second spool, the moving speed of the second spool being electrically changeable;
a second control device that controls the second movement mechanism and is capable of communicating with the first control device;
The first control device or the second control device outputs an error signal when the steering command received by the first control device is different from the steering command received by the second control device. 11. The method according to any one of claims 1 to 10,
The switching valve is connected to the pump by a return line.

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