Power steering apparatus of watercraft with propeller

Abstract

In a power steering apparatus of a watercraft 1 with propeller having a steering handle provided in a bow end of a hull, a propeller provided in a stern end of the hull, and a steering assist apparatus interposed in a steering force transmission path transmitting a steering force applied to the steering handle to the propeller, the steering assist apparatus is arranged in an intermediate portion of a steering cable constructing a propelling force transmission path.

1 . A power steering apparatus of a watercraft with propeller comprising:
 a steering handle provided in a bow end of a hull;   a propeller provided in a stern end of the hull; and   a steering assist apparatus interposed in a steering force transmission path transmitting a steering force applied to the steering handle to the propeller,   wherein the steering assist apparatus is arranged in an intermediate portion of a steering cable constituting the propelling force transmission path.   
   
   
       2 . The power steering apparatus of a watercraft with propeller as claimed in  claim 1 , wherein the steering assist apparatus is arranged in a gunwale side of the center of the hull. 
   
   
       3 . The power steering apparatus of a watercraft with propeller as claimed in  claim 1 , wherein the steering assist apparatus is provided with a torque sensor detecting a steering torque applied to the steering handle, a control unit controlling the steering assist apparatus, and a motor assisting the steering operation within a gear case. 
   
   
       4 . The power steering apparatus of a watercraft with propeller as claimed in  claim 2 , wherein the steering assist apparatus is provided with a torque sensor detecting a steering torque applied to the steering handle, a control unit controlling the steering assist apparatus, and a motor assisting the steering operation within a gear case. 
   
   
       5 . The power steering apparatus of a watercraft with propeller as claimed in  claim 1 , wherein an output side of the steering assist apparatus is provided with a screw reaction force suppressing apparatus setting up against an inverse input applied to the steering cable from a side of the propeller on the basis of a rotational reaction force of a screw provided in the propeller. 
   
   
       6 . The power steering apparatus of a watercraft with propeller as claimed in  claim 2 , wherein an output side of the steering assist apparatus is provided with a screw reaction force suppressing apparatus setting up against an inverse input applied to the steering cable from a side of the propeller on the basis of a rotational reaction force of a screw provided in the propeller. 
   
   
       7 . The power steering apparatus of a watercraft with propeller as claimed in  claim 3 , wherein an output side of the steering assist apparatus is provided with a screw reaction force suppressing apparatus setting up against an inverse input applied to the steering cable from a side of the propeller on the basis of a rotational reaction force of a screw provided in the propeller. 
   
   
       8 . The power steering apparatus of a watercraft with propeller as claimed in  claim 4 , wherein an output side of the steering assist apparatus is provided with a screw reaction force suppressing apparatus setting up against an inverse input applied to the steering cable from a side of the propeller on the basis of a rotational reaction force of a screw provided in the propeller. 
   
   
       9 . A power steering apparatus of a watercraft with propeller as claimed in  claim 5 , wherein the steering assist apparatus coaxially couples an input shaft and an output shaft via a torsion bar, and pivots the input shaft and the output shaft to the gear case, and
 wherein the screw reaction force suppressing apparatus is constructed by a braking means applying a constant braking force to the output shaft.   
   
   
       10 . A power steering apparatus of a watercraft with propeller as claimed in  claim 6 , wherein the steering assist apparatus coaxially couples an input shaft and an output shaft via a torsion bar, and pivots the input shaft and the output shaft to the gear case, and
 wherein the screw reaction force suppressing apparatus is constructed by a braking means applying a constant braking force to the output shaft.   
   
   
       11 . A power steering apparatus of a watercraft with propeller as claimed in  claim 7 , wherein the steering assist apparatus coaxially couples an input shaft and an output shaft via a torsion bar, and pivots the input shaft and the output shaft to the gear case, and
 wherein the screw reaction force suppressing apparatus is constructed by a braking means applying a constant braking force to the output shaft.   
   
   
       12 . A power steering apparatus of a watercraft with propeller as claimed in  claim 8 , wherein the steering assist apparatus coaxially couples an input shaft and an output shaft via a torsion bar, and pivots the input shaft and the output shaft to the gear case, and
 wherein the screw reaction force suppressing apparatus is constructed by a braking means applying a constant braking force to the output shaft.   
   
   
       13 . A power steering apparatus of a watercraft with propeller as claimed in  claim 5 , wherein the screw reaction force suppressing apparatus is constructed by an input side member to which a motor torque of an electric assist motor is input, an output side member from which the motor torque is output, and a static side member in which a rotation is constrained, and comprises a lock means which is provided between the static side member and the output side member and locks the output side member and the static side member with respect to an inverse input torque from the output side member, an unlocking means which is provided in the input side member and unlocks the lock state by the lock means with respect to the motor torque from the input side member, and a torque transmitting means which is provided between the input side member and the output side member and transmits the motor torque from the input side member to the output side member at a time when the lock state by the lock means is unlocked. 
   
   
       14 . A power steering apparatus of a watercraft with propeller as claimed in  claim 6 , wherein the screw reaction force suppressing apparatus is constructed by an input side member to which a motor torque of an electric assist motor is input, an output side member from which the motor torque is output, and a static side member in which a rotation is constrained, and comprises a lock means which is provided between the static side member and the output side member and locks the output side member and the static side member with respect to an inverse input torque from the output side member, an unlocking means which is provided in the input side member and unlocks the lock state by the lock means with respect to the motor torque from the input side member, and a torque transmitting means which is provided between the input side member and the output side member and transmits the motor torque from the input side member to the output side member at a time when the lock state by the lock means is unlocked. 
   
   
       15 . A power steering apparatus of a watercraft with propeller as claimed in  claim 7 , wherein the screw reaction force suppressing apparatus is constructed by an input side member to which a motor torque of an electric assist motor is input, an output side member from which the motor torque is output, and a static side member in which a rotation is constrained, and comprises a lock means which is provided between the static side member and the output side member and locks the output side member and the static side member with respect to an inverse input torque from the output side member, an unlocking means which is provided in the input side member and unlocks the lock state by the lock means with respect to the motor torque from the input side member, and a torque transmitting means which is provided between the input side member and the output side member and transmits the motor torque from the input side member to the output side member at a time when the lock state by the lock means is unlocked. 
   
   
       16 . A power steering apparatus of a watercraft with propeller as claimed in  claim 8 , wherein the screw reaction force suppressing apparatus is constructed by an input side member to which a motor torque of an electric assist motor is input, an output side member from which the motor torque is output, and a static side member in which a rotation is constrained, and comprises a lock means which is provided between the static side member and the output side member and locks the output side member and the static side member with respect to an inverse input torque from the output side member, an unlocking means which is provided in the input side member and unlocks the lock state by the lock means with respect to the motor torque from the input side member, and a torque transmitting means which is provided between the input side member and the output side member and transmits the motor torque from the input side member to the output side member at a time when the lock state by the lock means is unlocked.