Patent Application
20160039510
The disclosure of Japanese Patent Application No. 2014-163305 filed on Aug. 11, 2014, including specification, drawings and claims is incorporated herein by reference in its entirety.
The invention relates to an electric outboard motor.
In the related art, an electric outboard motor using an electric motor as a power source has been known.
For example, as shown in
The middle unit 102 is provided with a gear deceleration device 130 configured by a drive gear 131 and a driven gear 132. The driven gear 132 is arranged in front of the drive gear 131. An output shaft of the electric motor 114 is coupled to the drive gear 131, and an upper end portion of the drive shaft 121 is coupled to the driven gear 132. In the meantime, the drive shaft 121 extends downwards to couple a lower end portion thereof to the propeller shaft 122.
The lower mount 112 is arranged below the driven gear 132 and the swivel unit 117 is arranged at the front of the driven gear 132. That is, the gear deceleration device 130, the electric motor 114 and the drive shaft 121 are offset rearwards with respect to the swivel unit 117 so as to avoid interference with the swivel unit 117. The electric outboard motor 100 (swivel unit 117) is configured to rotate (tilt up/down) in an upward and downward direction about the tilt shaft 118 serving as a support point.
Patent Document 1: Japanese Patent Application Publication No. 2005-162055A
However, the technology disclosed in Patent Document 1 has a problem that the middle unit 102 is enlarged because the electric motor 114, the drive shaft 121 and the like are offset rearwards so as to avoid the swivel unit 117. Also, the technology disclosed in Patent Document 1 has a problem that the number of components and a weight increase because the useless components such as the motor cover 115 and the mount case 111 are provided.
Also, according to the technology of Patent Document 1, since the lower case 120 functioning as a rudder is offset rearwards with respect to the swivel unit 117, it is difficult to shorten an interval D1 (offset amount) between a center C of a lateral rudder force (lift force of the rudder) acting on the lower case 120 and a shaft center of the swivel unit 117. For this reason, the technology of Patent Document 1 has a problem that a large force is required to operate the rudder. Further, the technology of Patent Document 1 has a problem that a large force is required to tilt up the electric outboard motor 100 because an interval D2 between a shaft center of the electric motor 114, which is a heavy object, and the shaft center of the swivel unit 117 increases.
It is an object of the present invention to provide an electric outboard motor capable of reducing a size, a weight and a steering load and enabling a tilt operation to be easily performed.
According to an aspect of the embodiments of the present invention, there is provided an electric outboard motor comprising: an upper unit provided to be rotatable in a horizontal direction about a swivel unit; and a lower unit provided below the upper unit and configured to function as a rudder, wherein the upper unit comprises an electric motor supported by a rear side of the swivel unit via a mount unit, wherein the upper unit or lower unit has a gear deceleration device configured to couple an output shaft of the electric motor and a drive shaft extending in an upward and downward direction to each other, wherein the drive shaft is coupled to the gear deceleration device in front of the output shaft of the electric motor and configured to transmit an output of the electric motor to a propeller provided in the lower unit, and wherein the gear deceleration device is arranged below the swivel unit so as to overlap with the swivel unit in a front and rear direction.
With the above configuration, since the gear deceleration device is arranged below the swivel unit so as to overlap with the swivel unit, as seen from above, the gear deceleration device does not interfere with the swivel unit. Therefore, as compared to a configuration where the gear deceleration device is arranged at the rear of the swivel unit, the gear deceleration device, the electric motor and the drive shaft are provided at positions close to the swivel unit. For this reason, it is possible to make the upper unit small. Since the lower unit is also provided at a position close to the swivel unit, it is possible to reduce an interval (offset amount) between a center of a lateral lifting force acting on the lower unit serving as a rudder and the swivel unit. Thereby, the steering load is reduced to improve the operability of a hull operator. Further, it is possible to bring the electric motor, which is a heavy object, close to the swivel unit. Therefore, the hull operator can easily perform a tilt operation (tilt up or tilt down operation) of the electric outboard motor.
The gear deceleration device may be provided in the upper unit, and the lower unit may be detachably provided with respect to the upper unit.
With the above configuration, by separating the lower unit from the upper unit, an operator can efficiently check, maintain, repair and replace the respective components. In particular, it is possible to easily perform the maintenance (for example, the maintenance of the vicinity of the propeller) where it is not required to detach the gear deceleration device.
The gear deceleration device may be provided in the upper unit and comprise a gear case having a plurality of gears provided therein, the gear case may have an upper gear case provided at an upper side and a lower gear case provided at a lower side, and the upper gear case may be integrally formed with a motor housing having a rotor and a stator of the electric motor provided therein.
With the above configuration, since the upper gear case of the gear case is integrally formed with the motor housing, it is possible to reduce the number of components. Also, since the upper gear case and the motor housing are integrally formed and are thus reinforced each other, it is possible to improve the durability.
The mount unit may be integrally formed with a motor housing having a rotor and a stator of the electric motor provided therein.
With the above configuration, it is possible to omit the motor cover provided to cover the electric motor so as to improve the stiffness in the related art. Thereby, it is possible to reduce the number of components and to save the weight. Also, since the mount unit and the motor housing are integrally fanned and are thus reinforced each other, it is possible to improve the stiffness.
According to the present invention, it is possible to reduce the size, the weight and the steering load and to easily perform the tilt operation.
In the accompanying drawings:
Hereinafter, a preferred illustrative embodiment of the present invention will be described with reference to the accompanying drawings.
An electric outboard motor 3 of the illustrative embodiment is described with reference to
As shown in
The power supply unit 2 has a battery pack 2a and a battery housing case 2b. For example, an assembly of lithium ion battery cells is housed in an external case, so that the battery pack 2a is configured. The battery pack 2a is detachably provided in the battery housing case 2b. The battery pack 2a detached from the battery housing case 2b is charged by a charger (not shown) and is thus repeatedly used. The battery housing case 2b is provided with a coupler 2c for connecting one end portion of a power supply cable 5 thereto. In the meantime, the power supply unit 2 may have a charging function.
The electric outboard motor 3 has an upper unit 3a provided at an upper side and a lower unit 3b provided at a lower side, and is configured to be dividable in an upward and downward direction.
The upper unit 3a includes an upper unit case 10, a motor unit 11 and a bracket device 12.
The upper unit case 10 is integrally formed of a synthetic resin, for example, and configures a main outward appearance of the upper unit 3a. In the upper unit case 10, the motor unit 11 is arranged.
The motor unit 11 includes an electric motor 15, a control device 16 and a gear deceleration device 17. Also, the motor unit 11 has a water jacket (not shown) configured to enable cooling water for cooling the electric motor 15 to pass therethrough. In the meantime, the cooling method of the electric motor 15 is not limited to the water cooling method, and an air cooling method may also be adopted.
The electric motor 15 is configured by a rotor and a stator (all of which are not shown) provided in a motor housing 20. The motor housing 20 is formed by casting metal such as iron, aluminum and the like. The motor housing 20 has an upper housing 21 positioned at an upper side and a lower housing 22 positioned at a lower side and is configured to be dividable in the upward and downward direction.
The upper housing 21 has a substantially cylindrical shape of which an upper surface is closed and a lower surface is opened. The lower housing 22 has a substantial disc shape for closing the lower surface of the upper housing 21. The rotor and stator are arranged between the upper housing 21 and the lower housing 22 with an output shaft 15a extending from the rotor facing downwards vertically. The output shaft 15a protrudes downwards through a shaft hole 22a formed at the lower housing 22. In the meantime, the upper housing 21 is fixed to the lower housing 22 by a plurality of bolts (not shown), for example.
As shown in
As shown in
As shown in
The gear deceleration device 17 is configured to decelerate and output rotation of the electric motor 15. The gear deceleration device 17 includes a gear case 30, a drive gear 33 and a driven gear 34.
The gear case 30 is formed by casting metal such as iron, aluminum and the like. The gear case 30 has an upper gear case 31 positioned at an upper side and a lower gear case 32 positioned at a lower side.
The upper gear case 31 is formed integrally with the lower housing 22 of the motor housing 20. The upper gear case 31 is arranged on a lower surface of the lower housing 22 and has a substantial tray shape of which a lower side is opened. The upper gear case 31 extends more forwards than the lower housing 22. The lower gear case 32 closes the lower surface of the upper gear case 31 to configure a gear chamber R for arranging therein gears 33, 34. The lower gear case 32 is formed at its front side with a funnel part 32a tapered from an upper side towards a lower side. In the meantime, the lower gear case 32 is fixed to the upper gear case 31 by a plurality of bolts (not shown), for example. The shaft hole 22a of the lower housing 22 is formed to penetrate the upper gear case 31 and to communicate with the gear chamber R.
The drive gear 33 and the driven gear 34 are supported to be rotatable in a horizontal direction (around a rotary shaft extending in the upward and downward direction) in the gear case 30 (gear chamber R). The drive gear 33 is arranged on the same shaft center as the output shaft 15a of the electric motor 15. The driven gear 34 is arranged in front of the drive gear 33 and is meshed with the drive gear 33.
The gear deceleration device 17 is configured to couple the output shaft 15a of the electric motor 15 and a drive shaft 35 extending in the upward and downward direction to each other via the drive gear 33 and driven gear 34. Specifically, the output shaft 15a is configured to pass through the shaft hole 22a and to spline-couple with a shaft center part of the driven gear 34 at its lower end portion. The drive shaft 35 extends downwards through a shaft hole 32b formed at a lower end portion of the funnel part 32a. In the meantime, although described in detail later, the drive shaft 35 is configured to transmit an output of the electric motor 15 to a propeller 52 provided in the lower unit 3b.
The bracket device 12 includes a swivel unit 40 and a clamp unit 44.
The swivel unit 40 has a substantially cylindrical shape extending in the upward and downward direction and is arranged in front of the electric motor 15 and above the gear deceleration device 17. The swivel unit 40 is bridged between the respective upper mount units 23 and the lower mount unit 24 integrally formed with the motor housing 20. The swivel unit 40 is provided with an upper swivel bracket 41 and a lower swivel bracket 42.
The upper swivel bracket 41 is fixed by bolts (not shown) fastened to the bolt holes 23a of the respective upper mount units 23. As shown in
The electric motor 15 is supported by a rear side of the swivel unit 40 via the pair of upper and lower mount units 23, 24. Also, the upper unit 3a having the electric motor 15 fixed therein is provided to be rotatable in the horizontal direction about the swivel unit 40.
As shown in
A steering handle 47 extending forwards is attached to an upper part of the swivel unit 40 via a handle bracket 46. The steering handle 47 has a substantially cylindrical shape, which is long in the front and rear direction, and is configured to be rotatable in the horizontal direction about the swivel unit 40. In the meantime, the steering handle 47 is connected with the handle bracket 46 via a rotary pin 48. The steering handle 47 is configured to be rotatable rearwards about the rotary pin 48 (refer to an arrow in
A tip portion of the steering handle 47 is provided with a throttle grip 47a. The throttle grip 47a is electrically connected to the control device 16 by a cable (not shown). The control device 16 is configured to control the rotation number of the electric motor 15 in accordance with a rotating amount of the throttle grip 47a. In the meantime, an upper surface of the steering handle 47 is provided with a shift switch (not shown) configured to switch forward and reverse rotations of the electric motor 15.
Subsequently, the lower unit 3b is described with reference to
The lower unit case 50 is integrally formed of a synthetic resin, for example, and configures a main outward appearance of the lower unit 3b. The lower unit case 50 has a substantial plate shape functioning as a rudder. In the lower unit case 50, the drive shaft 35 extending downwards from the driven gear 34 of the gear deceleration device 17 is pivotally supported.
The drive shaft 35 extends from an upper end portion to a lower part of the lower unit case 50. A lower end portion of the drive shaft 35 is coupled to the propeller shaft 51 via a bevel gear 53. The propeller shaft 51 extends in the front and rear direction and is pivotally supported in the lower unit case 50. A rear end portion of the propeller shaft 51 extends rearwards from a lower-rear surface of the lower unit case 50. The propeller 52 is attached to the rear end portion of the propeller shaft 51.
Here, operations of the outboard motor system 1 are described. In the meantime, it is assumed that the electric outboard motor 3 is attached to the transom 4a of the hull 4 by the clamp unit 44.
When a hull operator rotates the throttle grip 47a, the control device 16 feeds the power from the power supply unit 2 to the electric motor 15 in accordance with a rotating amount of the throttle grip 47a. The rotor (output shaft 15a) of the electric motor 15 is rotated by the fed power. The output shaft 15a rotates the drive shaft 35 via the gear deceleration device 17 (respective gears 33, 34). The drive shaft 35 rotates the propeller 52 via the bevel gear 53 and propeller shaft 51. Then, the rotation of the propeller 52 propels the hull 4 on the water.
Subsequently, the steering of the electric outboard motor 3 is described. When the hull operator rotates the steering handle 47 in one side of the horizontal direction, the upper unit 3a and lower unit 3b including the electric motor 15 supported by the swivel unit 40 are rotated in the other side of the horizontal direction. Thereby, the lower unit case 50 serving as a rudder and the propeller 52 are displaced in the other side of the horizontal direction, so that the advancing direction of the hull 4 can be changed (steered).
Subsequently, a tip operation of the electric outboard motor 3 is described. The hull operator tilts up the electric outboard motor 3 when not using the electric outboard motor 3, for example. First, the hull operator folds rearwards the steering handle 47. Then, the hull operator rotates upwards the upper unit 3a and lower unit 3b about the tilt pin 45, thereby lifting up the propeller 52 and the like from the water. Thereby, the tilt up operation is completed. On the other hand, when using the electric outboard motor 3, the hull operator performs an operation (tilt down operation) reverse to the tilt up operation.
In the illustrative embodiment, the lower unit 3b of the electric outboard motor 3 is detachably mounted with respect to the upper unit 3a. When separating the lower unit 3b from the upper unit 3a, the drive shaft 35 is pulled out from the driven gear 34. By separating the lower unit 3b from the upper unit 3a, the operator can efficiently check, maintain, repair and replace the respective components. In particular, it is possible to easily perform the maintenance (for example, the maintenance of the vicinity of the propeller 52 and, the propeller shaft 51) where it is not required to detach the gear deceleration device 17.
As shown in
Since the lower unit 3b is also provided at a position close to the swivel unit 40, a center C of the lateral lifting force acting on the lower unit 3b (lower unit case 50) serving as a rudder is also close to the swivel unit 40. Therefore, it is possible to reduce an interval D3 (offset amount) between the center C of the lifting force of the rudder and the shaft center of the swivel unit 40, as compared to the interval D1 (refer to
Further, it is possible to bring the electric motor 15, which is a heavy object, close to the swivel unit 40. Therefore, it is possible to reduce an interval D4 between the shaft center of the electric motor 15 and the shaft center of the swivel unit 40, as compared to the interval D2 (refer to
Also, according to the electric outboard motor 3 of the illustrative embodiment, since the upper gear case 31 of the gear case 30 is integrally formed with the motor housing 20, it is possible to reduce the number of components. Also, since the upper gear case 31 and the motor housing 20 are integrally formed and are thus reinforced each other, it is possible to improve the durability.
Further, according to the electric outboard motor 3 of the illustrative embodiment, the pair of upper and lower mount units 23, 24 is integrally formed with the motor housing 20. Therefore, it is possible to omit the motor cover 115 (refer to
In the meantime, the gear deceleration device 17 of the electric outboard motor 3 of the illustrative embodiment is provided in the upper unit 3a. However, the present invention is not limited thereto. For example, the gear deceleration device 17 may be provided in (the upper part of) the lower unit 3b.
In the meantime, according to the electric outboard motor 3 of the illustrative embodiment, the pair of upper and lower mount units 23, 24 and the motor housing 20 are integrally formed. However, the present invention is not limited thereto. For example, the respective mount units 23, 24 configured as separate members from the motor housing 20 may be fixed to the motor housing 20 by bolts and the like. Also, the number of mount units is arbitrary. That is, one or more mount units may be provided.
The illustrative embodiment relates to an aspect of the electric outboard motor of the present invention, and the technical scope of the present invention is not limited thereto. The constitutional elements of the illustrative embodiment can be appropriately replaced or combined with the constitutional elements of the related art. The present invention defined in the claims is not limited by the descriptions of the illustrative embodiment.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2014-163305 | Aug 2014 | JP | national |
