JP2008025603A - Lubricating structure for outboard motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide lubricating structure for an outboard motor, capable of smoothing a flow of a lubricating oil, and capable of lubricating sufficiently a meshing part of a bevel gear mechanism. <P>SOLUTION: This lubricating structure is provided with a lubricating oil supply system 50 for supplying the lubricating oil c to the meshing part of an advancing bevel gear 18 with a driving bevel gear 17, using centrifugal force caused by rotation of the meshing part of the bevel gear mechanism. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an outboard motor having a drive shaft driven by an engine and a propeller shaft driven by the drive shaft via a bevel gear mechanism, and more particularly to a lubricating structure of a meshing portion of the bevel gear mechanism. .

  An outboard motor mounted on a small boat or the like generates a propulsive force by transmitting a rotational force of an engine from a drive shaft to a propeller shaft through a bevel gear mechanism.

  In this type of outboard motor, the lower case that accommodates and holds the drive shaft, the bevel gear mechanism, and the propeller shaft is directly subjected to the resistance of water during cruising. Therefore, the width of the lower case can be reduced as much as possible. Therefore, the installation space for the bevel gear mechanism and the like is limited.

  In order to extend the life of the meshing portion of each bevel gear mechanism and each bearing portion arranged in a limited space in such a lower case as much as possible, cooling is performed by circulating lubricating oil. In this circulation system, the lubricating oil is generally circulated among the bevel gear mechanism accommodation chamber, the drive shaft accommodation chamber, and the shift shaft accommodation chamber formed in the lower case.

However, since the forward bevel gear of the bevel gear mechanism is arranged at the boundary between the shift shaft accommodating chamber and the bevel gear mechanism accommodating chamber, the lubricating oil is difficult to flow and may stagnate, and the circulation is smooth. May not be performed. For this reason, in Patent Document 1, an oil passage that communicates the shift shaft accommodation chamber and the bevel gear mechanism accommodation chamber is formed in the forward bevel gear.
JP-A-5-321992

  By the way, as in the conventional structure described above, the flow of the lubricating oil can be performed smoothly only by forming an oil passage that connects the shift shaft housing chamber and the bevel gear mechanism housing chamber to the forward bevel gear. Insufficient lubrication of the meshing part. For this reason, there is a concern that the lubricating oil temperature of the meshing portion is likely to rise, and in some cases, the meshing portion is worn and the life of the bevel gear is shortened. In particular, in the above conventional publication, the lubricating oil that has passed through the oil passages of the forward and reverse bevel gears is a path that bypasses the meshing portion of the bevel gear mechanism, and it is difficult for a lubricating film to be formed between the tooth surfaces of the meshing portion. It has a structure.

  The present invention has been made in view of the above-described conventional situation, and provides an outboard motor lubrication structure that can smoothly flow the lubricating oil and sufficiently lubricate the meshing portion of the bevel gear mechanism. The purpose is that.

  The invention according to claim 1 is a lubricating structure for an outboard motor comprising a drive shaft driven by an engine and a propeller shaft driven by the drive shaft via a bevel gear mechanism. A drive bevel gear mounted on the drive shaft; a forward driven bevel gear mounted on the propeller shaft and meshed with the drive bevel gear; and a reverse driven bevel gear; Lubrication in which lubricating oil is supplied to the meshing portion of at least one of the driven bevel gears and the drive bevel gear through an oil introduction passage formed in the one of the driven bevel gears using a centrifugal force generated by rotation. It features an oil supply system.

  According to a second aspect of the present invention, in the first aspect, the oil introduction passage formed in the one driven bevel gear extends in an axial direction from an end portion on the opposite tooth surface side of the driven bevel gear and opens near the tooth surface. It is characterized by that.

  According to a third aspect of the present invention, in the first aspect, the oil introduction passage formed in the one driven bevel gear extends in the axial direction from the end portion on the opposite tooth surface side of the driven bevel gear, and further extends in the radial direction. It is characterized by being open to the root surface.

  According to a fourth aspect of the present invention, in the second or third aspect, the opening of the end portion on the side opposite to the tooth surface of the oil introduction passage is formed so as to be substantially opposed to the rotational direction of the driven bevel gear. Yes.

  According to a fifth aspect of the present invention, in the first aspect, the oil introduction passage formed in the one driven bevel gear is relative to the rotation axis as it goes from the end portion on the opposite tooth surface side of the driven bevel gear to the tooth surface side. And is formed so as to be inclined outward.

  A sixth aspect of the present invention is characterized in that, in the fifth aspect, a pipe member is inserted into the opening of the end portion on the opposite tooth surface side of the oil introduction passage so as to protrude toward the opposite tooth surface side.

  A seventh aspect of the invention is characterized in that, in the sixth aspect, the projecting portion of the pipe member is formed such that the opening of the projecting portion is substantially opposed to the rotational direction of the driven bevel gear.

  According to the lubricating structure of the present invention, the lubricating oil is supplied to the meshing portion of the bevel gear mechanism using the centrifugal force of the forward and reverse driven bevel gears. Is forcibly supplied to the meshing portion of the bevel gear mechanism. As a result, the lubricating oil temperature at the meshing portion is lowered, and a lubricating film is reliably formed between the tooth surfaces. As a result, wear of the meshing portion can be suppressed and the life of the bevel gear can be extended.

  According to the second aspect of the present invention, the driven bevel gear is formed with the oil introduction passage extending in the axial direction from the end portion on the side opposite to the tooth surface and opening in the vicinity of the tooth surface. It functions as a centrifugal pump that is transferred to the meshing portion via this, and the flow of the lubricating oil and the lubrication of the meshing portion can be performed reliably.

  In the invention of claim 3, the driven bevel gear is formed with an oil introduction passage extending in the axial direction from the end portion on the opposite tooth surface side and further extending in the radial direction to open to the tooth bottom surface. Since it functions as a centrifugal pump that transfers oil to the meshing part via the oil introduction passage, the lubricating oil can be directly supplied to the tooth bottom surface, and the meshing part can be more reliably lubricated.

  In the invention of claim 4, since the opening of the end portion on the side opposite to the tooth surface of the oil introduction passage is formed so as to be substantially opposed to the rotation direction of the driven bevel gear, the opening from the opening is caused by the centrifugal force accompanying the rotation of the driven bevel gear. The intake of the lubricating oil is promoted, and the flow of the lubricating oil and the lubricity of the meshing portion can be further enhanced.

  In the fifth aspect of the invention, since the oil introduction passage is formed in the driven bevel gear so as to incline outward with respect to the rotation axis as it goes from the end portion on the side opposite to the tooth surface to the tooth surface side, Due to the force, the flow rate of the lubricating oil flowing in the oil introduction passage is increased, and the flow of the lubricating oil and the lubrication of the meshing portion can be performed more reliably.

  In the invention of claim 6, since the pipe member is inserted into the opening of the end portion on the side opposite to the tooth surface of the oil introduction passage so as to protrude to the side opposite to the tooth surface, the lubricating oil from the pipe member due to the centrifugal force of the driven bevel gear Incorporation will be promoted.

  In the seventh aspect of the invention, since the projecting portion of the pipe member is formed so as to be substantially opposed to the rotational direction of the driven bevel gear, the intake of the lubricating oil can be further enhanced.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  FIGS. 1 to 5 are views for explaining an outboard motor lubrication structure according to a first embodiment of the present invention. FIG. 1 is a side view of an outboard motor mounted on a hull, and FIG. 2 is an outboard motor. FIG. 3 is a cross-sectional view of a lubricating portion of the propulsion device, and FIGS. 4 and 5 are a front view and a cross-sectional side view of the driven bevel gear. Note that front and rear and left and right in this embodiment mean front and rear and left and right when viewed from the rear of the hull.

  In the figure, reference numeral 1 denotes an outboard motor mounted on the stern 2 a of the hull 2. The outboard motor 1 is supported by a clamp bracket 3 fixed to the stern 2 a so as to be swingable up and down via a swivel arm 4, and supported so as to be steerable right and left via a pivot shaft 5.

  In the outboard motor 1, an upper case 8 is coupled to the upper surface of a lower case 7 in which the propulsion device 6 is accommodated, an engine 10 is mounted on the upper surface of the upper case 8, and the outer periphery of the engine 10 is surrounded. It has a schematic structure with a cowling 11 attached. The engine 10 is arranged vertically so that the crankshaft 10a is substantially vertical when traveling on water.

  The propulsion device 6 is connected to the crankshaft 10a so as to be coaxial, is driven to rotate by the engine 10, and is disposed in a substantially horizontal direction so as to be orthogonal to the drive shaft 12. A propeller shaft 14 that is rotationally driven by a shaft 12 via a bevel gear mechanism 13, the lower case 7 that accommodates and holds the propeller shaft 14 and the drive shaft 12, and a protrusion that protrudes rearward from the lower case 12 of the propeller shaft 14. And a propeller 15 attached to the portion 14a.

  The bevel gear mechanism 13 is always meshed with the drive bevel gear 17 and the drive bevel gear 17 that are mounted so as to rotate together with the lower end portion 12 a that is the bevel gear mechanism mounting portion of the drive shaft 12, and the propeller shaft 14. A forward bevel gear 18 and a reverse bevel gear 19 that are rotatably mounted on a front end portion 14b that is a bevel gear mechanism mounting portion.

  The forward bevel gear 18 has a spiral toothed bevel gear structure, and as shown in FIGS. 4 and 5, a bevel portion 18c is formed on a shaft portion 18b having a shaft hole 18a into which the propeller shaft 14 is inserted. The umbrella portion 18c has a structure in which a number of spiral teeth 18d are formed at predetermined intervals in the circumferential direction.

  Each of the swirling teeth 18d extends so as to form a curve located on the forward side in the rotational direction A from the inner end portion 18d 'to the outer end portion 18d' 'of the swirling teeth 18d, and therefore the adjacent swirling teeth 18d, 18d. Is formed so as to increase from the inner diameter side pitch W2 to the outer diameter side pitch W1. The drive bevel gear 17 and the reverse bevel gear 19 have a spiral bevel gear structure corresponding to the forward bevel gear 18.

  The bevel gear mechanism 13 includes a forward / reverse switching mechanism 20. The forward / reverse switching mechanism 20 is disposed between the front and rear bevel gears 18 and 19 of the propeller shaft 14, and is a dog clutch spline-fitted to the propeller shaft 14 so as to be movable in the axial direction and to rotate together. 21, a shift sleeve 22 inserted in the front end portion 14 b of the propeller shaft 14 so as to be slidable in the axial direction, a shift shaft 24 connected to the shift sleeve 22 via a shift cam 23, and a connection to the shift shaft 24 And a shift lever (not shown) disposed on the hull 2 side. The shift sleeve 22 is connected to the dog clutch 21 by a pin 25. The pin 25 is disposed in a pin hole 14 e formed between the front and reverse bevel gears 18 and 19 of the propeller shaft 14.

  The dog clutch 21 is movable between a neutral position that does not mesh with any of the forward and reverse bevel gears 18 and 19 and a forward and backward clutch-in position that meshes with either the forward or reverse bevel gears 18 and 19. It has become.

  When the shift lever is switched from the neutral position to any one of the forward and backward clutch-in positions, the shift shaft 24 rotates, and the shift cam 23 converts the rotation of the shift shaft 24 into the longitudinal movement of the shift sleeve 22. The dog cuticle 21 meshes with either the forward or reverse bevel gears 18 and 19. Thereby, the rotational force of the drive shaft 12 is transmitted to the propeller shaft 14.

  The lower case 7 is formed to have a substantially bullet shape in a cross-sectional view orthogonal to the drive shaft 12. A drive shaft housing chamber 7a extending in the vertical direction and opening upward is formed at a substantially central portion of the lower case 7 in the front-rear direction, and the drive shaft 12 is housed in the drive shaft housing chamber 7a.

  A bevel gear mechanism accommodating chamber 7b extending in the front-rear direction and opening rearward is formed at the lower end of the drive shaft accommodating chamber 7a, and the bevel gear mechanism 13 is accommodated in the bevel gear mechanism accommodating chamber 7b. ing.

  A cylindrical bearing housing 30 for oil-tight sealing between the drive shaft housing chamber 7a and the housing chamber 7a is inserted into the upper end opening of the drive shaft housing chamber 7a. The housing 30 is provided with a pair of upper and lower sealing materials 31 and 31 for oil-tight sealing with the drive shaft 12.

  An upper end 12b of the drive shaft 12 in the lower case 7 is pivotally supported by the housing 30 via a needle bearing 32, and a lower end 12a is a needle disposed in a lower end opening of the drive shaft accommodating chamber 7a. It is supported by a bearing 33.

  A tapered roller bearing 35 that pivotally supports the forward bevel gear 18 is disposed at the front end of the bevel gear mechanism accommodating chamber 7b, and the reverse bevel gear 19 is pivoted at the rear end opening via a gear housing 36, which will be described later. A supporting ball bearing 37 is arranged.

  A shift chamber accommodating chamber 7c is formed in front of the drive shaft accommodating chamber 7a of the lower case 7 so as to extend in parallel with the drive shaft accommodating chamber 7a, and the shift shaft 24 is accommodated in the shift shaft accommodating chamber 7c. ing. The lower end opening of the shift shaft accommodating chamber 7c communicates with the front end portion of the bevel gear mechanism accommodating chamber 7b.

  The forward bevel gear 18 and the tapered roller bearing 35 are disposed so as to substantially close the communicating portion 7i in the communicating portion 7i that communicates the shift shaft accommodating chamber 7c and the bevel gear mechanism accommodating chamber 7b. A seal member 38 that oil-tightly seals between the shift shaft 24 and the shift shaft 24 is inserted into the upper end opening of the shift shaft accommodating chamber 7c.

  A cooling water suction passage 7d is formed on the front side of the shift shaft housing chamber 7c so as to extend in parallel with the shift shaft housing chamber 7c, and the cooling water suction passage 7d has left and right side wall portions of the lower case 7. The cooling water flows in from the suction port 7g formed in.

  The lower case 7 is formed with a cooling water jacket 7h surrounding the outer periphery of the drive shaft housing chamber 7a, and the lubricating oil in the drive shaft housing chamber 7a is cooled by the cooling water flowing in the cooling water jacket 7h. . The lubricating oil in the shift shaft housing chamber 7c is cooled by the cooling water flowing through the cooling water suction passage 7d and the cooling water jacket 7h.

  An exhaust gas discharge passage 7e is formed at the rear side of the drive shaft housing chamber 7a of the lower case 7, and the cooling water jacket 7h is disposed between the exhaust gas discharge passage 7e and the drive shaft housing chamber 7a. ing. The discharge passage 7e communicates with a discharge port 7f formed in the rear end surface of the lower case 7. The exhaust gas from the engine 10 passes through the upper case 8 and is discharged into the water from the discharge port 7f through the exhaust gas discharge passage 7e.

  The above-described gear housing 36 disposed so as to pass through the exhaust gas discharge passage 7e is inserted into the bevel gear mechanism accommodation chamber 7b of the lower case 7. The gear gear housing 36 defines the exhaust gas discharge passage 7e and the bevel gear mechanism housing chamber 7b.

  The gear housing 36 includes a cylindrical body portion 36b in which a propeller shaft accommodating hole 36a is formed, a bowl-shaped large-diameter portion 36c formed to bulge outwardly from the front end portion of the cylindrical body portion 36b, The rear end portion of the cylindrical body portion 36b has a plurality of ribs 36d formed so as to extend radially outward in a direction perpendicular to the axis, and an annular flange portion 36e that connects the outer peripheral surfaces of the ribs 36d. .

  The flange portion 36e is fixed to the peripheral edge portion of the discharge port 7f of the lower case 7 by a plurality of bolts 40 inserted from the rear. The exhaust gas is discharged into the water from between the ribs 36d of the discharge port 7f.

  The outer peripheral surface of the large-diameter portion 36c is oil-tightly attached to the rear end opening of the bevel gear mechanism accommodating chamber 7b, and the ball bearing 37 is attached to the inner peripheral surface of the large-diameter portion 36c. .

  The propeller shaft 14 is inserted into the propeller shaft receiving hole 36a of the gear housing 36. The front end portion 14b of the propeller shaft 14 is inserted through the shaft holes 18a and 19a of the front and rear bevel gears 18 and 19, and through a metal bearing 42 disposed in the shaft hole 18a of the forward bevel gear 18. It is supported for relative rotation. A gap is formed between the propeller shaft 12 and the shaft hole 19 a of the reverse bevel gear 19.

  A pair of front and rear sealing members 44, 44 for oil-tight sealing between the propeller shaft 12 and the propeller shaft 12 are disposed at the rear end portion of the propeller shaft accommodation hole 36a of the gear housing 36.

  A needle bearing 43 that pivotally supports the rear end portion 14d of the propeller shaft 14 is disposed on the front side of the seal material 44 of the propeller shaft accommodation hole 36a of the gear housing 36.

  The propulsion device 6 includes an oil circulation system 47 that circulates the lubricating oil filled in the lower case 7. The oil circulation system 47 circulates lubricating oil in the drive shaft housing chamber 7a, the bevel gear mechanism housing chamber 7b, the shift shaft housing chamber 7c, and the propeller shaft housing hole 36a. The oil surface of the lubricating oil is located at the upper needle bearing 32 portion in the drive shaft housing chamber 7a, and the oil surface is at the same height in the shift shaft housing chamber 7c.

  The oil circulation system 47 includes a drive shaft circulation system 48 that circulates the lubricating oil a from the mounting portion of the drive bevel gear 17 of the drive shaft 12 through the upper and lower needle bearings 32 and 33 and through the forward / reverse switching mechanism 20; And a propeller shaft circulation system 49 that circulates the lubricating oil b through the needle bearing 43 that pivotally supports the rear end portion 14d of the propeller shaft 14 from the mounting portion 14b of the forward bevel gears 18 and 19 on the front of the propeller shaft 14. . Further, as shown in FIG. 3, a lubricating oil supply system 50 that supplies the lubricating oil c to the meshing surface of the forward bevel gear 18 and the drive bevel gear 17 by utilizing the centrifugal force accompanying the rotation of the forward bevel gear 18. Is provided.

  The drive shaft circulation system 48 includes an oil passage 48a extending in the axial direction formed in a gap between the drive shaft 12 and the drive shaft housing chamber 7a of the lower case 7, an axial center portion of the drive shaft 12, and a drive shaft housing chamber. The screw pump part 48b formed by the inner peripheral wall of 7a, and the return channel | path 48c which connects the needle bearing 32 part of the upper end part of the said oil channel | path 48a, and the shift shaft accommodation chamber 7c.

  The screw pump portion 48b is formed by providing a slight gap between the spiral groove 12c formed on the outer peripheral surface of the drive shaft 12 and extending in the counterclockwise direction upward, and the inner peripheral wall of the drive shaft accommodating chamber 7a. Thus, the lubricating oil in the oil passage 48a is pressurized and transferred upward.

  When the drive shaft 12 rotates, the screw pump portion 48b moves upward in the oil passage 48a while pressurizing the lubricating oil. The lubricating oil a that has risen in the oil passage 48a lubricates the needle bearing 32 and flows from here through the return passage 48c into the shift shaft accommodating chamber 7c, and the sliding portions and the tapered rollers of the forward / reverse switching mechanism 20. After the bearing 35 is lubricated, it returns to the bevel gear mechanism accommodation chamber 7b. The lubricating oil a in the bevel gear mechanism accommodating chamber 7b is transferred upward while lubricating the meshing portion of the bevel gear mechanism 13 and the lower needle bearing 33 by the screw pump portion 48b.

  The lubricating oil a flowing in the drive shaft housing chamber 7a and the shift shaft housing chamber 7c is cooled by the cooling water flowing in the cooling water jacket 7h.

  The propeller shaft circulation system 49 extends in the axial direction from the front end portion 14b of the forward and reverse bevel gears 18 and 19 to the vicinity of the needle bearing 43, and further extends in the diameter direction in the vicinity of the needle bearing 43. It has an oil passage 49c that opens, and a return passage 49d that is formed in the gap between the propeller shaft 14 and the propeller shaft accommodation hole 36a of the gear housing 36.

  When the dock clutch 21 is engaged with either the forward or reverse bevel gears 18 and 19 by the shift lever switching operation, the propeller shaft 14 rotates, and the lubricating oil b is ejected from the opening of the oil passage 49c by the centrifugal force of the propeller shaft 14. The jetted lubricating oil b lubricates the needle bearing 43, passes through the return passage 49d from here, lubricates the meshing portion of the ball bearing 37 and the bevel gear mechanism 13, and returns to the bevel gear mechanism accommodating chamber 7b. Lubricating oil b in the bevel gear mechanism accommodating chamber 7b flows into the oil passage 49c by the rotation of the propeller shaft 14.

  The lubricating oil supply system 50 is constituted by an oil introduction passage 50a formed in the shaft portion 18b of the forward bevel gear 18 at a predetermined interval in the circumferential direction. Each oil introduction passage 50 a extends in parallel with the rotation axis C of the forward bevel gear 18. The inflow port 50b of the oil introduction passage 50a opens to the counter tooth surface side end surface 18e of the forward bevel gear 18, and the outflow port 50c opens to the tooth surface side end surface 18f.

  The tooth surface side end surface 18f is formed so as to form a vertical surface perpendicular to the rotation axis C. The counter tooth surface side end surface 18e is formed so as to form a tapered surface inward with respect to the rotation axis C, and the inflow port 50b is opened in the tapered surface. Thereby, the inflow port 50b is substantially opposed to the rotation direction A of the forward bevel gear 18.

  The lubricating oil a in the shift shaft accommodating chamber 7c is introduced from the inlet 50b of the oil introduction passage 50a by the centrifugal force accompanying the rotation of the forward bevel gear 18, and the introduced lubricating oil c passes through the oil introduction passage 50a. It flows out from the outlet 50c toward the tooth 18d. In this case, the lubricating oil c flowing out from each oil introduction passage 50a is ejected radially so as to be directed to each tooth 18d of the umbrella portion 18c. The jetted lubricating oil c is supplied to the meshing portion between the forward bevel gear 18 and the drive bevel gear 17 and flows to the oil passage 48a side through the meshing portion.

  According to the present embodiment, the forward bevel gear 18 is formed with the oil introduction passage 50a that extends in parallel with the rotation axis C from the anti-tooth surface end surface 18e and opens to the tooth surface end surface 18f. Since the centrifugal force of the bevel gear 18 is used to supply the meshing portion between the forward bevel gear 18 and the drive bevel gear 17, the lubricating oil c is transferred from the shift shaft accommodating chamber 7c to the bevel gear mechanism accommodating chamber 7b. It can flow smoothly and can be supplied to the meshing portion of the forward bevel gear 18 and the drive bevel gear 17. As a result, the lubricating oil temperature at the meshing portion of the forward bevel gear 18 is lowered, and a lubricating film is formed on the surface of each tooth 18d. As a result, wear of the bevel gear mechanism 13 can be suppressed and the life can be extended.

  Here, the oil introduction passage 50a may be inclined so as to be away from the rotation axis C toward the outlet 50c. If it does in this way, lubricating oil can be more reliably supplied to the said meshing part with a centrifugal force.

  In this embodiment, since the oil introduction passage 50a constituting the lubricating oil supply system 50 is formed in the shaft portion 18b of the forward bevel gear 18, the forward bevel gear 18 takes in the lubricating oil c into the oil introduction passage 50a. Thus, the flow of the lubricating oil c and the lubrication of the meshing portion can be performed reliably.

  In the present embodiment, the inlet 50b of the oil introduction passage 50a is formed in a tapered shape so as to be substantially opposite to the rotation direction A of the forward bevel gear 18, so that the flow is caused by the centrifugal force accompanying the rotation of the forward bevel gear 18. The intake of the lubricating oil c from the inlet 50b is promoted, and the flow of the lubricating oil c and the lubrication of the meshing portion of the bevel gear mechanism 13 can be further enhanced.

  In the above embodiment, the oil introduction passage 50a is provided on the forward bevel gear 18 side. However, the oil introduction passage of the present invention may be provided on the reverse bevel gear side, and the front and reverse umbrellas may be provided. You may provide in both gears.

  FIG. 6 is a diagram for explaining a modification of the first embodiment. In the figure, the same reference numerals as those in FIG. 3 denote the same or corresponding parts.

  The lubricating oil supply system 50 of the present embodiment is configured by an oil introduction passage 50a formed in the shaft portion 18b of the forward bevel gear 18 at a predetermined interval in the circumferential direction.

  Each of the oil introduction passages 50a includes a shaft hole 50d extending in parallel with the rotation axis C from the counter tooth surface side end surface 18e of the shaft portion 18b of the forward bevel gear 18, and a shaft extending in the radial direction from the tip portion of the shaft hole 50d. It is comprised from the cross hole 50e. The axis crossing hole 50e is opened at the bottom surface between the adjacent teeth 18d and 18d of the umbrella portion 18c.

  According to the present embodiment, the oil introduction passage 50a formed in the forward bevel gear 18 is provided with the shaft hole 50d extending in the rotation axis direction from the counter tooth surface side end surface 18e, and the tooth bottom surface extending in the radial direction from the shaft hole 50d. Since the forward bevel gear 18 functioning as the centrifugal pump allows the lubricating oil c to be directly supplied to the bottom surface of the tooth 18d, the forward bevel gear 18 and the drive bevel gear 17 are configured. Can be more reliably lubricated.

  In addition, the shaft hole 50d may be inclined so as to be away from the rotation axis C toward the outflow port side, and in this way, the lubricating oil can be more reliably supplied to the meshing portion by centrifugal force.

  7 to 11 are views for explaining the lubricating structure of the outboard motor according to the second embodiment of the present invention. FIG. 7 is a side view of the lower case of the outboard motor, and FIGS. 8 to 11 are bevel gears. It is the front view, rear view, sectional view, and principal part sectional view of the forward bevel gear of the mechanism. In the figure, the same reference numerals as those in FIGS. 3 to 5 denote the same or corresponding parts.

  As shown in FIG. 7, the oil circulation system 47 of the present embodiment is configured so that the lubricant a is attached to the mounting portion 12 a of the drive bevel gear 17 of the drive shaft 12, the upper and lower needle bearings 32 and 33, and the forward / reverse switching mechanism. A drive shaft circulation system 48 that circulates between the propeller shaft 14, a front end of the propeller shaft 14, a mounting portion 14 b of the reverse bevel gears 18 and 19, and a needle that pivotally supports the rear end portion 14 d of the propeller shaft 14. The propeller shaft circulation system 49 that circulates between the bearing 43 and the forward and reverse bevel gears 18 and 19 and the drive bevel gear using the centrifugal force generated by the rotation of the forward and reverse bevel gears 18 and 19 with the lubricating oil c. 17 is provided with a lubricating oil supply system 51 for supplying to the meshing surface with 17, and the basic structure is substantially the same as in the first embodiment.

  The lubricating oil supply system 51 of the present embodiment is configured by oil introduction passages 51a and 51b formed at predetermined intervals in the circumferential direction in the forward and reverse bevel gears 18 and 19, respectively.

  Each oil introduction passage 51a of the forward bevel gear 18 is inclined so as to be positioned outward with respect to the rotation axis C from the counter tooth surface side end surface 18e to the tooth surface side end surface 18f of the forward bevel gear 18 (FIG. 10). (A)) and is inclined so as to be positioned upstream in the rotational direction A (FIG. 10B).

  The inflow port 51c of the oil introduction passage 51a is open to the anti-tooth side end surface 18e, and the outflow port 51d is open to the tooth surface side end surface 18f. As a result, the outlet 51d is located at a position offset radially outward from the inlet 51c and offset upstream in the rotational direction.

  The oil introduction passage 51b of the reverse bevel gear 19 is formed upright to form an angle of approximately 60 degrees with respect to the rotation axis of the reverse bevel gear 19. The inlet 51e of the oil introduction passage 51b opens to the shaft hole 19a, and the outlet 51f opens to the tooth bottom surface (see FIG. 7).

  According to the present embodiment, the forward bevel gear 18 is formed with the oil introduction passage 51a that is inclined outward with respect to the rotation axis C as it goes from the counter tooth surface end surface 18e to the tooth surface side end surface 18f. 18, the rotational speed of the oil introduction passage 51a on the outlet 51d side is higher than that of the inlet 51c, and therefore the centrifugal force on the outlet 51d side is also higher than that of the inlet 51c. As a result, the flow velocity of the lubricating oil c flowing in the oil introduction passage 51a increases toward the outlet 51d side, and the flow of the lubricating oil c and the lubrication of the meshing portion between the forward bevel gear 18 and the drive bevel gear 17 can be further enhanced. it can.

  Further, the reverse bevel gear 19 is formed with an oil introduction passage 51b that is inclined outward in the same manner as described above, and the outlet 51f of the oil introduction passage 51b is opened at the tooth bottom surface. And the drive bevel gear 17 can be directly supplied to the meshing portion.

  12 and 13 are views for explaining the lubricating structure of the outboard motor according to the third embodiment of the present invention. In the figure, the same reference numerals as those in FIGS. 10 and 11 denote the same or corresponding parts.

  The oil introduction passage 51a of the present embodiment is formed so as to be inclined outward with respect to the rotation axis C as it goes from the counter tooth surface side end surface 18e of the forward bevel gear 18 to the tooth surface side end surface 18f. The structure is the same as in the second embodiment.

  And the pipe member 52 is inserted in the inflow port 51c opened to the anti-tooth surface side end surface 18e of the said oil introduction channel | path 51a so that it may protrude ahead from the anti-tooth surface side end surface 18e. The protruding portion 52 a of the pipe member 52 is located on the rear side of the front end face 18 ′ of the forward bevel gear 18.

  In the present embodiment, since the pipe member 52 is inserted on the inlet 51c side of the oil introduction passage 51a so as to protrude forward from the counter-tooth side end surface 18e, the lubricating oil c due to the centrifugal force accompanying the rotation of the forward bevel gear 18 is obtained. Will be promoted.

  FIG. 14 shows a first modification of the third embodiment.

  In the first modification, the projecting portion 52a of the pipe member 52 is bent inward so that the opening 52b thereof faces the rotational direction of the forward bevel gear 18. Thus, since the opening 52b is made to oppose in the rotation direction, the intake of the lubricating oil c by the pipe member 52 can be further ensured.

  FIG. 15 shows a second modification of the third embodiment.

  In the second modification, pipe members 52 and 53 are inserted into the inlet 51c side and the outlet 51d side of the oil introduction passage 51a, respectively. The protrusion 52a of the pipe member 52 on the inlet side is bent inward so that the opening 52b thereof faces the rotational direction of the forward bevel gear 18, and the protrusion 52a of the pipe member 53 on the outlet side is The opening 52b is bent so as to follow the rotational direction of the forward bevel gear 18. In this modification, both intake and discharge of the lubricating oil can be performed reliably.

1 is a side view of an outboard motor according to a first embodiment of the present invention. It is sectional drawing of the propulsion apparatus of the said outboard motor. It is sectional drawing of the bevel gear mechanism lubrication part of the said propulsion apparatus. It is the figure seen from the tooth surface side of the forward bevel gear of the said bevel gear mechanism. It is sectional drawing of the said forward bevel gear. It is sectional drawing of the bevel gear mechanism lubrication part which shows the modification of the said 1st Embodiment. It is a side view of the lower case in which the propulsion device by a 2nd embodiment of the present invention was stored. It is the figure seen from the tooth surface side of the forward bevel gear of the said propulsion apparatus. It is the figure seen from the counter-tooth surface side of the said forward bevel gear. It is sectional drawing of the said forward bevel gear. It is principal part sectional drawing of the oil introduction channel | path of the said forward bevel gear. It is sectional drawing of the forward bevel gear by 3rd Embodiment of this invention. It is principal part sectional drawing of the oil introduction channel | path of the said forward bevel gear. It is sectional drawing of the forward bevel gear which shows the 1st modification of the said 3rd Embodiment. It is sectional drawing of the forward bevel gear which shows the 2nd modification of the said 3rd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Outboard motor 10 Engine 12 Drive shaft 13 Bevel gear mechanism 14 Propeller shaft 17 Drive bevel gear 18 Forward bevel gear 19 Reverse bevel gear 50, 51 Lubricating oil supply system 50a, 51a, 51b Oil introduction passage 50b, 51a Tooth surface opening)
50c, 51d Outlet (tooth side opening)
52, 53 Pipe member 52a, 53a Protruding part 52b, 53b Opening A A Rotating direction of forward bevel gear C Rotating axis c Lubricating oil

Claims (7)

In an outboard motor lubrication structure comprising a drive shaft driven by an engine and a propeller shaft driven by the drive shaft via a bevel gear mechanism,
The bevel gear mechanism includes a drive bevel gear mounted on the drive shaft, a forward driven bevel gear mounted on the propeller shaft and meshed with the drive bevel gear, and a reverse driven bevel gear.
An oil introduction passage formed in one of the driven bevel gears at a meshing portion between at least one of the driven bevel gears and the drive bevel gear using centrifugal force associated with the rotation of the forward and reverse driven bevel gears A lubricating structure for an outboard motor, comprising a lubricating oil supply system for supplying lubricating oil through a shaft. The oil introduction passage formed in the one driven bevel gear according to claim 1 extends in an axial direction from an end portion on the side opposite to the tooth surface of the driven bevel gear and opens near the tooth surface. Lubrication structure for outboard motors. In Claim 1, the oil introduction passage formed in the one driven bevel gear extends in the axial direction from the end portion on the counter tooth surface side of the driven bevel gear, further extends in the radial direction, and opens to the tooth bottom surface. An outboard motor lubrication structure characterized by 4. An outboard motor lubrication structure according to claim 2, wherein the opening at the opposite end of the oil introduction passage is substantially opposite to the rotational direction of the driven bevel gear. . 2. The oil introduction passage formed in the one driven bevel gear according to claim 1, wherein the oil introduction passage is inclined outward with respect to the rotation axis from the end portion on the side opposite to the tooth surface of the driven bevel gear. An outboard motor lubrication structure characterized by being formed. 6. The outboard motor lubrication structure according to claim 5, wherein a pipe member is inserted into the opening of the oil introduction passage at the end portion on the opposite tooth surface side so as to protrude toward the opposite tooth surface side. 7. The outboard motor lubrication structure according to claim 6, wherein the projecting portion of the pipe member is formed so that an opening of the projecting portion is substantially opposed to a rotation direction of the driven bevel gear.

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