JP2012236562A - Power transmission device of outboard motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power transmission device of an outboard motor that is superior in power transmission efficiency and significantly improves vibration control performance and operability or the like.SOLUTION: An outboard motor is configured to store an engine 11 in an engine case 100 and has a propulsion machine 15, driven by the engine 11, outside the engine case 100. A speed reducer 32 is connected to the output side of the engine 11. An input shaft 82 from the engine 11 and an output shaft 87 to the propulsion machine 15 are arranged in parallel with each other on the same side with respect to the speed reducer 32. A one-way clutch 89 is mounted onto the output shaft 87 of the speed reducer 32.

Description

  The present invention relates to a power transmission device that is arranged in the middle of a power transmission system from an engine that is a power source to a propeller that is a final output end in an outboard motor.

  Major outboard propulsion engines or propulsion systems include outboard motors, inboard motors, and inboard motors. Outboard motors are called outboard drives, etc., and are composed of an engine, its catchers, drive system gears, shafts, screws, etc., and are generally mounted on a transom board at the stern of the hull. . Typically, it is mounted on a small boat or the like and has a steering function and a tilting function.

  Inboard / outboard motors are called inboard engines / outboard drives, etc., as a method of installing propulsion engines for small vessels, etc., and the engine is mounted on the stern part of the ship and the reduction gear, forward / reverse clutch, propeller, etc. are integrated. This is a drive unit arranged outside the transom board.

  In the power transmission system from the engine that is the power source to the propeller that is the final output end, the support structure of the engine and the power transmission mechanism and their arrangement are extremely important in relation to higher output and more efficient power transmission. There are various ideas. For example, Patent Document 1 or Patent Document 2 discloses a typical suspension method for a large outboard motor. In these cases, a mount is placed on the tip side of the tilt shaft and the steering shaft, and the entire engine and propulsion unit are supported by the mount. In addition, the entire engine and propulsion device can be tilted and steered. The mount consists of four axes parallel to the longitudinal axis. When the engine and the propulsion unit are integrally suspended as described above, engine vibration and propulsive force (propeller thrust and rudder force) are simultaneously applied to the mount.

In the inboard / outboard motor described in Patent Document 3, the engine is mounted, and the propulsion unit is fixed to the hull independently of the engine. Therefore, the propulsive force can be transmitted to the hull while absorbing the engine vibration.
Moreover, in the irregular outboard motor described in Patent Document 4 and the like, only the engine is an independent suspension, and the propulsion device is connected by a universal joint.

US Pat. No. 7,244,152 JP 2006-31379 A Japanese Patent No. 3038606 Japanese Patent No. 2789362

  In the above-described Patent Document 1 or Patent Document 2, since engine vibration and propulsive force are not directly related, it is substantially difficult to appropriately control the propulsive force without transmitting the engine vibration to the hull. Met. That is, in order to absorb engine vibration, a soft mount is necessary, and the attitude of the outboard motor changes due to the propulsive force, or a delay occurs with respect to the steering operation. On the other hand, if a hard mount is used, engine vibration cannot be absorbed.

In the one described in Patent Document 3, the inboard / outboard motor has the tilt shaft and the steering shaft at the center of the universal joint of the drive shaft. Since the bending angle of the universal joint is limited, both the tilt angle and the steering angle are smaller than those of the outboard motor. Therefore, there is a problem that the rudder is difficult to work and the turning performance is poor.
Moreover, the thing described in patent document 4 etc. has the same merit and demerit as an inboard / outboard motor at the point that only the engine was suspended independently and the propulsion unit was connected by the universal joint.
In a further example, when the engine is mounted and the propulsion unit is independently attached to the hull, it does not impair accurate steering operation due to the vibration isolation of the engine, but it does not have a tilt mechanism and therefore includes obstacles including the seabed. Since the impact cannot be absorbed when it collides with, it has problems such as being unsuitable for small ships.

  In view of such circumstances, an object of the present invention is to provide a power transmission device for an outboard motor that is excellent in power transmission efficiency and greatly improves vibration isolation performance and operability.

  The power transmission device for an outboard motor according to the present invention includes an engine housed in an engine case, and an outboard motor provided with a propulsion device driven by the engine outside the engine case. A reduction gear is connected, and the input shaft from the engine and the output shaft to the propulsion device are arranged in parallel to each other on the same side with respect to the reduction gear.

  In the power transmission device for an outboard motor according to the present invention, a one-way clutch is mounted on the output shaft of the speed reducer to regulate the power transmission direction.

  In the power transmission apparatus for an outboard motor according to the present invention, only the engine is floatingly supported in the outboard motor, and the engine and the propulsion unit are connected via a universal joint.

  Further, in the power transmission device for an outboard motor according to the present invention, the engine is arranged so that an output side thereof is on an outer side in the width direction of the engine case, and the speed reducer is installed on an outermost side in the width direction of the engine case. The propulsion unit is connected via the universal joint.

  According to the present invention, a large output torque can be obtained by decelerating with a reduction gear in the power transmission system. As a result, it is possible to obtain an improvement in propeller efficiency that exceeds the amount of friction generated by the reduction gear. In addition, by installing a one-way clutch on the output shaft of the speed reducer, the driving side engine can be operated in a fuel-efficient state at low loads, and the friction of the resting side engine is not transmitted. Can be improved. Furthermore, although a relative displacement or vibration occurs between the engine unit and the propulsion device, such a displacement can be effectively absorbed by a universal joint or the like.

It is a perspective view which shows the example of the ship or boat which mounts the outboard motor which concerns on this invention. It is a perspective view which shows the external appearance of the outboard motor of this invention. It is a rear view which shows the external appearance of the outboard motor of this invention. It is a side view which shows the external appearance of the outboard motor of this invention. It is a front view which shows the external appearance of the outboard motor of this invention. It is a perspective view which shows the structural example inside the engine case in the outboard motor of this invention. It is a disassembled perspective view of the main components inside the engine case in the outboard motor of the present invention. It is a perspective view which shows the structure and arrangement example of the engine unit of the outboard motor of this invention. It is a perspective view which shows the structure and arrangement example of the intake / exhaust system of the outboard motor of the present invention. It is a perspective view which shows the structure and arrangement example of the power transmission mechanism of the outboard motor of this invention. It is a perspective view which shows the structure and arrangement example of the frame of the outboard motor of this invention. It is a perspective view which shows the case cover open state in the engine case of the outboard motor of this invention. It is a fragmentary perspective view which shows the guide mechanism periphery of the swivel bracket in the outboard motor of this invention. It is a longitudinal cross-sectional view which shows the power transmission system around the swivel bracket of the outboard motor of the present invention. FIG. 3 is a side view showing the periphery of the power transmission device in the outboard motor of the present invention. It is a plane sectional view showing a power transmission system including a power transmission device in an outboard motor of the present invention. FIG. 4 is a cross-sectional view showing the periphery of the one-way clutch mounted on the power transmission device in the outboard motor of the present invention, and an enlarged view of a main part showing a configuration example of the one-way clutch. It is a side view which shows the modification of the power transmission device in the outboard motor of this invention.

Hereinafter, preferred embodiments of a power transmission device for an outboard motor according to the present invention will be described with reference to the drawings.
FIG. 1 shows an example of a ship or a boat equipped with an outboard motor 10 according to the present invention. In this example, the ship is typically small and medium, and has a transom board 2 (stern board) at the rear of the hull 1. The outboard motor 10 is mounted using the transom board 2 as shown. Note that, in the main points of the respective drawings referred to below, the front (the bow side) is indicated by an arrow Fr, and the rear (stern side) is indicated by an arrow Rr. Moreover, the left-right direction (ship width direction) of a hull is shown with the arrow L and the arrow R as needed.

  First, in the hull 1 according to the present embodiment, a ship floor 3 is laid at the bottom of the hull 1 as shown in FIG. 1, and a transom board 2 is disposed at the rear end of the ship floor 3. A cockpit 4 is provided in the vicinity of the center of the ship floor 3, and devices, instruments, instruments, and the like necessary for steering including the handle 5 are disposed in the cockpit 4. The outboard motor 10 is integrally equipped with power, a propulsion device, a steering device, a tilt device, and the like, and is configured as a so-called all-in-one type. The outboard motor 10 can be operated if there are normal equipment such as a fuel tank and a battery on the hull 1 side. is there.

  In addition, the ship is not limited to the illustrated example, and there is also a hull having a bracket for mounting an outboard motor on the rear side of the transom board, that is, a stern plate or a part corresponding to the stern plate on the stern of the hull. The outboard motor 10 of the present invention can be effectively applied to a type having members.

  2 to 5 show the exterior of the outboard motor 10, FIG. 2 is a perspective view of the outboard motor 10, FIG. 3 is a rear view, FIG. 4 is a side view, and FIG. The outboard motor 10 has a resin engine case 100. The engine unit 100 houses an engine unit as a power source, which will be described later, and a screw (propeller) is disposed below the rear of the engine case 100. To rotate the screw. The engine case 100 also functions as an exterior member that constitutes the exterior of the outboard motor 10 and exhibits an exterior with a sense of unity as a whole.

  Referring also to FIG. 1, engine case 100 is configured as a housing having substantially the same width as the stern portion (typically, transom board 2) of hull 1. In this example, the basic form of the engine case 100 is a substantially rectangular parallelepiped, and the longitudinal direction of the rectangular parallelepiped is the ship width direction. The engine case 100 includes a case main body 101 that houses the engine unit and its peripheral components or members, and a case cover 102 that covers an upper opening 101a (see FIG. 12) of the case main body 101.

  The engine unit housed in the engine case 100 and its peripheral parts will be described. The outboard motor 10 of the present invention uses an internal combustion engine as a main power as its power unit, and drives this to drive the propulsion unit. FIG. 6 shows a configuration example inside the engine case 100 in the outboard motor 10, and FIG. 7 is an exploded perspective view of a main configuration inside the engine case 100. In the engine case 100, the engine unit 11 constituting the power unit is arranged and accommodated in a compact and well-balanced manner. In this embodiment, two engine units 11 are provided, and a pair of engine units 11 are arranged in a center distribution on the left and right sides of an engine case 100 in which the longitudinal direction of the casing is the ship width direction. Each engine unit 11 is connected to an intake system 12 and an exhaust system 13, and a power transmission device 14 according to the present invention is connected to each output end (crankshaft). The power transmission device 14 is coupled to the propulsion unit 15 at the center in the left-right direction on the rear side of the engine unit 11, and these outboard motor components are mounted and supported on the frame 16 as shown in FIG.

  More specifically, the engine unit 11 uses a water-cooled in-line four-cylinder four-cycle gasoline engine in this example. The number of engine cylinders and the like can be appropriately changed as necessary, and is not limited to this example. Referring to FIG. 8, in engine unit 11, crankcase 17, cylinder block 18, cylinder head 19 and cylinder head cover 20 are integrally coupled so as to sequentially overlap, and an oil pan 21 is attached to the lowermost part. The crankshaft of each engine unit 11 is disposed along the ship width direction (left-right direction), and the engine output shaft coupled to the shaft end is disposed on both the left and right sides, that is, the engine of the right engine unit 11. The output shaft is arranged on the right side, and the engine output shaft of the left engine unit 11 is on the left side.

  Next, in the intake system 12, a single air cleaner 22 is disposed between the engine units 11 as shown in FIG. On the other hand, as shown in FIG. 8, intake manifolds 23 are coupled to the front side of the cylinder head 19 of the right engine unit 11 and to the rear side of the cylinder head 19 of the left engine unit 11, respectively. The air cleaner 22 is connected to each other via an intake pipe 24. An intake pipe 25 extends from the front surface of the air cleaner 22 to the hull 1 side in front of the engine case 100 (see FIG. 9), and takes in air from an air intake port at the tip thereof. The air intake is installed in a room or space that is not exposed to waves, splashes, rain, or the like in the hull 1. As shown in FIG. 8, each engine unit 11 branches from a single intake pipe 25 to a plurality (four in this example) of intake manifolds 23.

  In the exhaust system 13, as shown in FIG. 7 and the like, exhaust manifolds 26 are coupled to the rear side of the cylinder head 19 of the right engine unit 11 and to the front side of the cylinder head 19 of the left engine unit 11, respectively. Connected to a single exhaust pipe 27. An exhaust hose 28 is connected to the exhaust pipe 27, and a muffler 29 is connected to the exhaust hose 28. An exhaust hose 30 is connected to the muffler 29, and exhaust gas is discharged from an exhaust outlet 31 attached to the exhaust hose 30.

  The muffler 29 is installed outside the lower surface of the case body 101 of the engine case 100. In this case, the muffler 29, the exhaust hose 30 and the like are arranged so as not to substantially protrude from the lower surface of the case body 101, and the left and right sides of the rear side of the case body 101 are well balanced from the exhaust outlets 31 arranged near the lower portions. Exhausted into water.

  The power transmission device 14 transmits the output of the engine unit 11 to the propulsion device 15. In the power transmission device 14, a speed reducer 32 is connected to the engine output shafts of the left and right engine units 11 as shown in FIG. 10. A gear group is rotatably supported in a casing 33 of the speed reducer 32, and a tie rod 34 is connected to the output shaft. The left and right tie rods 34 are arranged concentrically and horizontally in the left-right direction, and are connected to the intermediate speed reducer 35 at the center in the left-right direction. Each tie rod 34 is connected to the reduction gear 32 and the intermediate reduction gear 35 via universal joints 36 and 37 at both ends. In addition, the tie rod 34 has a spray line engagement structure at an appropriate position in the axial direction, and the entire length can be expanded and contracted.

  In the present embodiment, the intermediate speed reducer 35 includes a pair of input side bevel gears coupled to the tie rods 34 and an output side bevel gear meshing with these input side bevel gears. The output side bevel gear is connected to the drive shaft in the drive shaft case 38, and the intermediate speed reducer 35, the drive shaft case 38, and the swivel bracket 39 are integrally coupled to each other. The drive shaft extends downward from the intermediate speed reducer 35. These swivel brackets 39 and the like are rotatably supported by the case body 101 through a bearing 40 as will be described later.

  As shown in FIG. 10 and the like, the propulsion unit 15 is disposed below the drive shaft case 38. The propulsion device 15 includes a gear case 41 containing a gear for driving a propeller, and has a fin shape as a whole. A propeller 42 is mounted on the rear end portion of the gear case 41. The drive shaft extends further downward through the drive shaft case 38 and extends into the gear case 41. A final reduction gear is configured in the gear case 41, and the propeller 42 can be rotationally driven through the final reduction gear.

  Further, a tilt mechanism and a steering mechanism for the propulsion device 15 are provided. Although a detailed description thereof will be omitted here, first, the intermediate speed reducer 35, the drive shaft case 38, and the entire propulsion unit 15 can be rotated up and down around the tilt axis by the tilt mechanism. The tilt axis T is set coaxially with the tie rod 34, and the propulsion unit 15 can tilt around the tilt axis T as indicated by an arrow A in FIG. The tilt mechanism may include a so-called power trim tilt (PTT) or the like, and an electrohydraulic tilt mechanism may be configured.

  Further, the propulsion unit 15 can be rotated around the steering shaft S in the yaw direction (left-right direction) (yawing) by the steering mechanism as indicated by an arrow B in FIG. In this steering mechanism, for example, it has a steering cylinder that is hydraulically driven in an electro-hydraulic manner, and the propulsion unit 15 rotates in the left-right direction, that is, performs a steering operation by reciprocating along a steering rod using a hydraulic pump as a hydraulic source. be able to.

  The main components of the outboard motor 10 described above are mounted and supported on the frame 16 as shown in FIG. The frame 16 is formed using a material such as a steel pipe so as to have an outer shape substantially along a rectangular parallelepiped of a casing constituting the engine case 100 as shown in FIG. A plurality of engine mounts 43 for mounting and supporting the engine unit 11 are disposed at predetermined portions of the frame 16, and the engine unit 11 is mounted on the frame 16 through the engine mounts 43. A main bracket 44 to which a bearing 40 for supporting the swivel bracket 39 and the like described above is attached is attached to the rear portion of the frame 16.

  Further, a plurality of transom bolts 45 are attached to the front portion of the frame 16 facing the front. Outboard motor components such as the engine unit 11 are mounted on the frame 16, and the frame 16 mounting them is housed in the engine case 100. The transom bolt 45 passes through the front surface portion of the case body 101 of the engine case 100 and is fastened to the transom board 2, whereby the entire engine case 100 can be fastened and fixed to the transom board 2. The transom bolt 45 protruding from the case main body 101 is fitted with a seal or packing to ensure water tightness.

  As described above, the engine case 100 includes the case main body 101 that houses the engine unit 11 and its peripheral components, and the case cover 102 that covers the upper opening 101 a of the case main body 101. When the case cover 102 is closed with respect to the case main body 101, the inside of the engine case 100 becomes a substantially sealed space, and high water tightness is ensured. In this case, the constituent members of the outboard motor 10 are supported by the frame 16, and the frame 16 holds the engine unit 11 and is responsible for the propulsive force and steering force of the propulsion unit 15, that is, the load on the engine case 100 itself. Does not take. Further, as shown in FIG. 1, the engine case 100 also functions as an exterior member of the outboard motor 10 and is mounted on the outboard motor 10 so as to exhibit a unity appearance as a whole.

  As shown in FIGS. 2 to 4 and the like, on the rear surface side of the case main body 101, in the region from the rear surface portion to the bottom surface portion, it is formed to be recessed inward of the case main body 101 at the center in the ship width direction. A recess 103 is provided. Around this recess 103, a propulsion unit 15 constituting the propulsion device, its tilt and steering mechanism, and the like are disposed. The recess 103 is formed from the rear side of the case main body 101 toward the front, and is necessary so that the tilt mechanism and the steering mechanism or peripheral devices and members thereof do not interfere with the case main body 101 when the tilt or steering operation is performed. A sufficient gap is provided.

  As described above, equipment such as a fuel tank and a battery is provided on the hull 1 side, and these equipment and the outboard motor 10 are connected or coupled. In this case, as shown in FIG. 5, a plurality of through-holes 104 are formed in the form of making a hole between the front portion of the casing 101 and the transom board 2. That is, a through hole 104A for inserting the intake pipe 25 for supplying combustion air to the engine, a through hole 104B for inserting a fuel pipe for supplying fuel from the fuel tank to the engine, and the inside of the engine case 100 A through-hole 104C for passing a cylinder for ventilation air for ventilating the air is formed. Further, a cord or cable for electrically (including a control signal) or mechanical connection between a device or equipment or member in the engine case 100 and the control device on the hull 1 side is inserted. A hole 104D is formed. These through holes 104 are provided with watertight holding means (seal or the like) when the intake pipe 25 or the like is mounted.

  The case cover 102 constitutes an upper surface portion of the engine case 100, and is coupled to be rotatable via a hinge 105 in the vicinity of the rear upper end of the case main body 101 as shown in FIG. 2 or FIG. As shown in FIG. 12, the case cover 102 is rotated around the hinge 105 and opened to open the inside of the engine case 100, and thus the exposed engine unit 11 and the like inside the engine case 100 can be freely accessed. Become. The case cover 102 can be opened to easily check the inside, and the convenience of this type of work can be improved.

  As shown in FIG. 12, a seal 106 is laid on the closing portion or mating surface of the case main body 101 and the case cover 102, and the case cover 102 is closed with respect to the case main body 101, so that the engine case 100 has high water tightness. Secured / held. In this case, the seal 106 is laid over the entire circumference along the mating surfaces of the case main body 101 and the case cover 102. When the case cover 102 is closed, the case cover 102 is sandwiched between the case body 102 and the closed portion of the case main body 101, thereby obtaining high water tightness with respect to the engine case 100. Further, when the case cover 102 is closed with respect to the case main body 101, a lock mechanism 107 as shown in FIG. 12 is provided to fix and hold the case cover 102 in its closed state.

  In addition, a holding mechanism capable of holding the case cover 102 in its open state is provided, and the case cover 102 can be held in an open state with respect to the case main body 101 as shown in FIG. In the specific configuration of the holding mechanism, a hydraulic damper 108 is disposed in the vicinity of the opening 101a of the case main body 101 as shown in FIG. The hydraulic damper 108 is coupled between the case cover 102 and the frame 16. Referring to FIG. 11, a pair of left and right support arms 16 a is provided at the upper rear of the frame 16, and one end of each hydraulic damper 108 is connected and supported to the support arm 16 a via a universal bearing 109. Similarly, the other end of the hydraulic damper 108 is connected to the back side of the case cover 102 via a universal bearing.

  In the above case, in addition to the constituent members of the outboard motor 10 described above, an electric signal or electric power is transmitted / received between the cooling piping system of the engine unit 11, the hydraulic piping system for driving the tilt mechanism and the steering mechanism, or between the members. An electric signal line or a cord for performing the operation is routed to an appropriate position in the engine case 100, and auxiliary machinery necessary for operating the outboard motor 10 is provided. An appropriate operation of the outboard motor 10 is performed through these piping systems or the like, or by operating auxiliary machinery.

  As described above, the engine unit 11 is mounted and supported on the frame 16 via the engine mount 43. Specifically, the frame 16 includes left and right side frames 46, an inner frame 47 substantially corresponding to the recess 103 in the width direction of the ship, a front frame 48 at the front, a rear frame 49 at the rear, as shown in FIG. It includes an upper upper frame 50, a lower lower frame 51, and the like, and is composed of a pipe material, a plate material, and a thick portion. These members are combined by welding, bolt connection, etc., and connected to each other.

  Corresponding to the concave portion 103 formed on the rear surface side of the case main body 101, the frame 16 inside the case main body 101 is also formed in a concave shape. In this case, a portion corresponding to the recess 103 of the rear frame 49 or the lower frame 51 is extended downward or inclined so as to have a truss structure as can be seen from FIG. Referring to FIG. 13 and the like, pads 52 are attached to the left and right sides of the swivel bracket 39 so as to come into contact with the case body 101 when the propulsion unit 15 is tilted. On the other hand, a pad 53 corresponding to the pad 52 is attached to the truss structure portion of the frame 16. By providing these pads 52 and 53, the propulsion device 15 is guided from both the left and right sides.

  As described above, the swivel bracket 39 is rotatably supported by the frame 16 via the bearing 40. Further, as shown in FIG. 11, a main bracket 44 to which a bearing 40 for rotatably supporting the swivel bracket 39 is attached is attached to and supported by the rear portion of the frame 16. In the center of the rear portion of the frame 16, a pair of donut-shaped flange portions 54 for attaching the main bracket 44 is provided. Although the case main body 101 is not shown in FIG. 11, the case main body 101, more specifically, the side wall of the recess 103 is interposed so as to be sandwiched between the main bracket 44 and the flange portion 54.

  The main bracket 44 is formed in a U shape in plan view (FIG. 11 and the like), and has a bearing housing 55 (bearing portion) for mounting the bearing 40 on both left and right sides of the U shape. Thus, the main bracket 44 including the left and right bearing housings 55 is integrally formed in a U-shape as a whole, so that the swivel bracket 39 can be supported with high rigidity. Therefore, sudden turning and tilting (trim) operation during turning can be performed smoothly and in a short time.

  Here, FIG. 14 shows a configuration example along a power transmission path from the intermediate reduction gear 35 to the propulsion device 15 supported via the swivel bracket 39. On both the left and right shoulders of the swivel bracket 39, a hollow cylindrical tilt suspension 56 that is coaxial with the tilt axis T is formed. The tilt suspension 56 is fitted with a bearing 40, and the bearing 40 is further fitted into the bearing housing 55 from both sides as described above. In this way, the swivel bracket 39 is supported by the tilt suspension 56 so as to be rotatable around the tilt axis T via the bearing 40, whereby the entire swivel bracket 39 can be tilted smoothly.

  In addition, a pair of input shafts 57 for the intermediate speed reducer 35 are rotatably supported via bearings 58 in the tilt suspension portions 56 coaxially with the tilt shaft T. A tie rod 34 is connected to one end side of the input shaft 57 via a universal joint 37. A bevel gear 59 that is a pinion gear is attached to the other end side of each input shaft 57. On the other hand, a drive shaft 60 is rotatably inserted and supported in a drive shaft case 38 integrally coupled with the swivel bracket 39, and a bevel gear 61 attached to the upper end of the drive shaft 60 is rotatable via a bearing 62. Supported by The bevel gear 61 meshes with both of the bevel gears 59 arranged to face each other. In this way, in the intermediate speed reducer 35, the power input from the tie rod 34 to the input shaft 57 is transmitted to the drive shaft 60 via the bevel gear 59 and the bevel gear 61, whereby the drive shaft 60 is rotationally driven.

  The drive shaft 60 further penetrates the propulsion unit 15 and extends to the gear case 41, and a bevel gear 63, which is a pinion gear, is attached to the lower end thereof. A propeller shaft 64 attached with a propeller 42 is rotatably supported in the gear case 41, and a bevel gear 65 attached to the propeller shaft 64 meshes with the bevel gear 63. As described above, the final reduction gear 66 is constituted by the bevel gear 63 and the bevel gear 65 in the gear case 41, and the propeller 42 is rotated through the power transmission system from the intermediate reduction gear 35 to the final reduction gear 66 in this way. ing.

  Further, a drive shaft housing 67 coaxial with the drive shaft 60 is rotatably supported in the drive shaft case 38, and the drive shaft 60 passes through the drive shaft housing 67. A lower case 68 is coupled to the lower portion of the drive shaft housing 67. A gear case 41 is provided below the lower case 68. The lower end of the drive shaft 60 is rotatably supported by the lower case 68 via a bearing 69.

  The drive shaft housing 67 is generally formed in a cylindrical shape, and is rotatably supported by the drive shaft case 38, that is, the thrust bracket 39 via bearings 70 and 71 near the upper end and the lower end, respectively. The drive shaft housing 67 is integrally coupled to the lower case 68 as described above, and the steering mechanism 76 is rotated around the steering axis S by the operation of the steering mechanism 76 to perform a steering operation. Further, a thrust receiver 72 is disposed at the upper end of the drive shaft housing 67. Bearings 73 and 74 are mounted on the upper and lower sides of the thrust receiver 72, and a bearing 75 is mounted near the lower portion of the drive shaft housing 67 so as to receive a thrust direction load by these swivel vertical axis thrust bearings. Yes.

  In the present invention, a gear train including a drive gear 77, idle gears 78 and 79, and a driven gear 80 is disposed in the casing 33 of the speed reducer 32 constituting the power transmission device 14 as shown in FIG. Composed. As will be described later, the drive gear 77 is connected to the output side of the crankshaft of the engine unit 11, and the rotational driving force of the crankshaft is decelerated or increased via the gear train and transmitted to the universal joint 36. Whether to decelerate or increase the speed by the gear train is appropriately selected depending on the size of the boat and the propeller to be used. In this embodiment, a spur gear is preferably used for the gear train. A required amount of lubricating oil is injected into the casing 33, and the gear train is lubricated using this lubricating oil.

  As shown in FIG. 16, the left and right engine units 11 are accommodated in the engine case 100, and an input shaft 82, which is an input shaft for the speed reducer 32, is placed on the right end of the crankshaft 81 on the engine output side of the right engine unit 11. Are attached by flange connection. Similarly, an input shaft 82 that is an input shaft for the speed reducer 32 is attached to the left end of the crankshaft 81 on the engine output side of the left engine unit 11 by flange connection. The left and right speed reducers 32 are rotationally driven by the crankshaft 81 of the engine unit 11 via the input shaft 82, respectively. Here, in each reduction gear 32, the drive gear 77, the idle gears 78 and 79, and the driven gear 80 are rotatably supported by bearings 83, 84, 85, and 86, respectively.

  An output shaft 87 that is an output shaft for the propulsion device 15 is attached to the driven gear 80 of each reduction gear 32. In this case, in each reduction gear 32, the output shafts 87 are arranged in parallel to each other on the same side as the input shaft 82. That is, the output shafts 87 of the right and left speed reducers 32 are provided so as to extend toward the propulsion device 15 disposed at the center of the engine case 100 in the ship width direction. Each output shaft 87 is flange-coupled to the drive shaft 36 a of the universal joint 36. The universal joint 36 is connected to the tie rod 34 disposed in parallel with the crankshaft 81 as described above.

  Here, as shown in FIG. 15A, the casing 33 of each reduction gear 32 is fastened and fixed to the engine unit 11 by a plurality of bolts 88 mainly around the drive gear 77 side. As already described, the engine unit 11 is mounted and supported on the frame 16 via the plurality of engine mounts 43. In this case, the engine mount 43 is typically configured using reinforced rubber, that is, the engine unit 11 is floatingly supported on the frame 16 by the engine mount 43, so-called floating support. For this reason, the speed reducer 32 itself is also floatingly supported on the frame 16 integrally with the engine unit 11.

  As described above, the casing 33 is bolted to the engine unit 11, while the swivel bracket 39 is supported by the frame 16. In this case, the speed reducer 32 side and the swivel bracket 39 side are connected via the universal joints 36 and 37 and the tie rod 34, thereby absorbing a relative positional error between them. This relative position error includes, for example, a combination of vibration caused by engine vibration and driving torque reaction force. The swivel bracket 39 is disposed at the center of the engine case 100, and the engine output end (the end of the crankshaft 81) is on the outside of both engine units 11. Therefore, the lengths of the universal joints 36 and 37 and the tie rod 34 are increased. Can be long. Since the inclination angle of the tie rod 34 with respect to the ship width direction when absorbing the position error becomes small, smooth operation is guaranteed. Further, since the drive shaft 36a of the universal joint 36 and the output shaft 87 are flange-coupled, the engine and the drive part can be easily detached and attached, which is very convenient for maintenance and the like.

  In the present embodiment, the one-way clutch is further shown in FIG. 15B or FIG. 16 in a simplified manner, but on one of the left and right speed reducers 32, in this example, on the output shaft 87 of the left speed reducer 32. 89 is installed. FIG. 17 shows the configuration around the one-way clutch 89 in detail. In the figure, a one-way clutch 89 is inserted between the output shaft 87 and the boss 80 of the driven gear 80. In addition, bearings 90 are mounted on the left and right sides of the one-way clutch 89, and an oil seal 91 is mounted on the outside thereof. The flange portion 87 a of the output shaft 87 and the drive shaft 36 a of the universal joint 36 are coupled by a bolt 92.

  As shown in FIG. 17 (b), the one-way clutch 89 has an outer ring 89A inserted between the output shaft 87 and the boss 80 of the driven gear 80, and a cam surface 89a is formed on the outer ring 89A. A roller guide hole 89b is provided. The outer ring 89A is coupled to the boss portion 80 side of the driven gear 80. A roller 93 is accommodated in the roller guide hole 89b, and an elastic unit 94 for elastically urging the roller 94 is mounted. The bullet unit 94 may be a coil spring type 94A or a retainer / spring type 94B. In either case, the outer ring 89A tries to rotate in the clockwise direction as shown by the arrow in the figure with respect to the output shaft 87, so that the roller 93 in the roller guide hole 89b is connected to the cam surface 89a by the spring action of the bullet means 94. Engage, ie bite. Thereby, the output shaft 87 is rotationally driven by the wedge action of both.

  In the present embodiment, as described above, the driven gear 80 and the output shaft 87 are directly coupled to the right engine unit 11, and the left engine unit 11 is coupled via the one-way clutch 89. Accordingly, in such a power transmission system, the propeller 42 is driven by the two engine units 11 at the time of acceleration and at high speed, but at the low speed, the engine speed of the left engine unit 11 is first reduced or stopped. Let On the other hand, when the left engine unit 11 is driven by the right engine unit 11 or the propeller reaction force (that is, engine brake), the clutch is automatically released. As a result, at the time of low output, only the right engine unit 11 is operated, thereby reducing pumping loss and friction loss and improving fuel efficiency. In this example, the engine unit 11 on the right side does not have the one-way clutch 89 and can therefore receive a reaction force from the propeller 42. Accordingly, it is possible to apply the engine brake during deceleration as in the conventional outboard motor, and the stopping distance of the boat can be shortened.

  In the above case, the speed reducer 32 may not use a gear train, that is, may be a belt drive. In this case, as shown in FIG. 18, corresponding to the drive gear 77 and the driven gear 80, a drive pulley 95 and a driven pulley 96 are provided instead of them, and a belt 97 is wound around them. In this case, the tensioner 98 is elastically contacted at an appropriate position in the middle of the belt 97 to ensure an appropriate tension of the belt 97.

  In the basic operation of the outboard motor 10 of the present invention, the outputs of the two engine units 11 juxtaposed inside the engine case 100 pass through the power transmission device 14 and the propulsion device 15 arranged outside the engine case 100. Is transmitted to. More specifically, when the engine unit 11 is started, the power is first input to the speed reducer 32 and then transmitted from the output end to the tie rod 34 via the universal joint 36. The engine power is further transmitted from the tie rod 34 to the intermediate speed reducer 35. In the intermediate speed reducer 35, the engine power is transmitted from the input shaft 57 to the drive shaft 60 via the bevel gear 59 and the bevel gear 61, whereby the drive shaft 60 is rotationally driven. Is done. The driving force of the drive shaft 60 is transmitted to the propeller shaft 64 and further to the propeller 42 via the bevel gear 63 and the bevel gear 65 in the final speed reducer 66 in the gear case 41, whereby the propeller 42 rotates.

Next, the characteristic configuration of the present invention and the operation and effect thereof will be described. First, the speed reducer 32 is connected to the output side of the engine unit 11, and the input shaft from the engine unit 11 to the speed reducer 32, that is, the input shaft. The input shaft 82 and the output shaft to the propulsion device 15, that is, the output shaft 87 are arranged in parallel to each other on the same side.
By arranging the input shaft 82 and the output shaft 87 in this way, the power transmission direction is reversed in the speed reducer 32, but by decelerating with the speed reducer 32, a large output torque can be obtained. Thus, by rotating the large-diameter propeller at a low speed, it is possible to obtain an improvement in propeller efficiency that exceeds the amount of friction generated by the speed reducer 32.

A one-way clutch 89 is mounted on the output shaft 87 of the speed reducer 32 so as to restrict the power transmission direction.
When one or both of the two engine units 11 are not driving the propulsion unit 15, power is not transmitted. Therefore, each engine unit 11 can be started or stopped independently. For example, the propulsion unit 15 is driven by a single engine unit 11 when the load is low, and the propulsion unit 15 is driven by both engine units 11 when the load is high. By adopting such a driving method, the driving side engine can be operated with good fuel consumption especially at low load, and the friction of the resting side engine is not transmitted, so that the fuel consumption of the engine unit 11 can be improved comprehensively. .

The engine unit 11 is supported in a floating manner in the engine case 100, and the engine unit 11 and the propulsion device 15 are connected to each other through universal joints 36 and 37 and a tie rod 34.
Since the engine is mounted for vibration isolation with respect to the frame 16 which is a chassis, it is relatively displaced or vibrated. Since the propulsion unit 15 does not require a vibration-proof mount with respect to the frame 16, it does not move or vibrate relatively. Accordingly, a relative displacement or vibration occurs between the engine unit 11 and the propulsion unit 15. Such relative displacement can be absorbed by the universal joints 36 and 37 and the tie rod 34.

  In a conventional outboard motor, an engine and a propulsion mechanism are mounted integrally, and steering and tilting are performed. In this respect, although the universal joint is not necessary, since the heavy engine and the entire propulsion unit are mounted together, the vibration isolation performance is insufficient as a whole, and the engine vibration is easily transmitted to the hull. In the present invention, unlike the conventional outboard motor, the propulsive force itself is not directly applied to the mount portion, but it is sufficient to absorb only the torque reaction force and the inertial force reaction force of the engine. Have. As a result, a compact mounting structure can be obtained. Further, even if the two engine units 11 are operated independently, vibrations are not transmitted to the hull 1 because they are mounted independently.

Further, the engine unit 11 is arranged so that the output side of the engine case 100 is on the outer side in the width direction of the engine case 100, and the speed reducer 32 is installed on the outermost side in the width direction of the engine case 100. Connected to the propulsion unit 15.
By arranging the reduction gear 32 and the propulsion device 15 in this manner, the effective lengths of the universal joints 36 and 37 and the tie rod 34 can be increased as described above. In other words, the universal joints 36 and 37 and the tie rod 34 having a sufficient length can be installed in the engine case 100 in a compact manner. Therefore, it is possible to secure a large amount of displacement that can be generated between the two, thereby improving the vibration isolation performance.

As mentioned above, although this invention was demonstrated with various embodiment, this invention is not limited only to these embodiment, A change etc. are possible within the scope of the present invention.
Although the case where the gear train of the speed reducer 32 has four stages has been described in the above embodiment, the number of stages can be appropriately increased or decreased according to the engine output or the like.

1 hull, 2 transom board, 3 ship floor, 6 through hole, 7 bottom, 10 outboard motor, 11 engine unit, 12 intake system, 13 exhaust system, 14 power transmission mechanism, 15 propulsion unit, 16 frame, 17 crankcase 18 cylinder block, 19 cylinder head, 20 cylinder head cover, 21 oil pan, 22 air cleaner, 23 intake manifold, 24 intake pipe, 25 intake pipe, 26 exhaust manifold, 27 exhaust pipe, 28 exhaust hose, 29 muffler, 30 exhaust hose , 31 Exhaust outlet, 32 Reducer, 33 Casing, 34 Tie rod, 35 Intermediate reducer, 36, 37 Universal joint, 38 Drive shaft case, 39 Swivel bracket, 40 Bearing, 41 Case, 42 Propeller, 43 Engine mount, 44 Main bracket, 45 Transom bolt, 46 Side frame, 47 Inner frame, 48 Front frame, 49 Rear frame, 50 Upper frame, 51 Lower frame, 52, 53 Pad, 54 Flange 55 bearing housing, 56 tilt suspension, 57 input shaft, 58 bearing, 59 bevel gear, 60 drive shaft, 61 bevel gear, 62 bearing, 63 bevel gear, 64 propeller shaft, 65 bevel gear, 66 final reducer, 67 drive shaft housing, 68 Lower case, 69, 70, 71 Bearing, 72 Thrust receiver, 73, 74, 75 Bearing, 77 Drive gear, 78, 79 Idle gear, 80 Revenue gear, 81 Crankshaft, 82 Input shaft, 82 Input shaft, 83, 84, 85, 86 Bearing, 87 Output shaft, 89 One-way clutch, 89A Outer ring, 93 Roller, 94 Bulleting means, 100 Engine case, 101 Case body, 102 Case cover, 103 recess, 104 through hole, 105 hinge, 106 seal, 107 lock mechanism, 108 hydraulic damper, 109 universal bearing.

Claims (4)

In an outboard motor having an engine housed inside the engine case and a propulsion device driven by the engine outside the engine case,
A ship having a reduction gear connected to an output side of the engine, and an input shaft from the engine and an output shaft to the propulsion device are arranged in parallel to each other on the same side with respect to the reduction gear. Power transmission device for external unit.   The power transmission device for an outboard motor according to claim 1, wherein a one-way clutch is mounted on an output shaft of the speed reducer to restrict a power transmission direction.   3. The power transmission device for an outboard motor according to claim 1, wherein only the engine is supported in a floating manner in the outboard motor, and the engine and the propulsion unit are connected via a universal joint.   The engine is arranged such that its output side is on the outer side in the width direction of the engine case, the speed reducer is installed on the outermost side in the width direction of the engine case, and is connected to the propulsion device through the universal joint. The power transmission device for an outboard motor according to claim 3.

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