JP6187103B2 - Outboard motor cooling system - Google Patents

Description

  The present invention relates to a cooling device for an outboard motor that takes in water from water outside the outboard motor with a cooling water pump and supplies cooling water to the engine unit side.

  A cooling water pump of an outboard motor equipped with a water-cooled engine is disposed in a gear case (lower case) that is submerged in water together with a propulsion device (propeller), as described in Patent Document 1, for example, to increase the driving force of the engine. It uses a kind of vane pump that is directly driven by a drive shaft that transmits to the propeller.

  The vane pump includes a cylindrical pump case and a rotor (impeller) that is housed in the pump case and rotates. The rotor is supported by a rotating shaft eccentric with respect to the pump case, and includes a plurality of vanes (blades) extending radially from the rotating shaft support portion, and these vanes are formed of an elastic material. Each vane is deformed in the radial direction so as to always contact the inner peripheral surface of the pump case.

JP 2004-211619 A

  In a conventional outboard motor cooling device, the vane pump has a large mechanical loss due to frictional contact between the vane and the pump case during operation. As a result, the fuel efficiency performance of the engine is affected, and the efficiency of the outboard motor must be reduced. Further, when foreign matter such as sand or mud is mixed in the cooling water to be sucked, the contact portion between the vane and the pump case is worn. For this reason, the pump performance deteriorates as it is, and it is necessary to periodically replace the rotor. Thus, the durability is not necessarily sufficient.

  An object of the present invention is to provide a cooling device for an outboard motor that effectively improves the efficiency and durability of the outboard motor.

An outboard motor cooling apparatus according to the present invention is an outboard motor cooling apparatus that takes in water from outside the outboard motor by a cooling water pump and supplies the cooling water to the engine unit side. The main pump disposed in the upper part of the outboard motor, and the sub pump disposed in the lower case provided in the lower part of the outboard motor and provided with the water intake, and the main pump is connected to the water intake of the lower case. Arranged in a main cooling water passage connecting the water jacket of the engine unit, and the sub pump is arranged in a bypass passage formed so as to bypass a part of the main cooling water passage on the water intake side of the main pump is, the cooling water transfer capability per unit time of the secondary pump, the main is set smaller than the pump, the cooling water transfer capability of the auxiliary pump, as the possible transfer of priming when activating the main pump Characterized in that it is set to the capacity of.

  In the outboard motor cooling apparatus of the present invention, the main pump is formed by a non-volumetric centrifugal pump, while the sub pump is formed by a volumetric vane pump.

In the outboard motor cooling device of the present invention, the water absorption side of the sub pump of the bypass passage is connected to the main cooling water passage below the water line where the ship is stopped.

  Further, in the outboard motor cooling device of the present invention, a check valve is provided in the main cooling water passage below the water line where the ship is stopped to prevent a reverse flow of cooling water to the intake port side. It is characterized by that.

Further, in the outboard motor cooling device of the present invention, the main pump is driven by an electric motor capable of adjusting the flow rate of cooling water in accordance with the cylinder wall temperature, and the sub pump supplies engine driving force to the propeller shaft of the lower case. It is driven by a drive shaft for transmission.

  According to the present invention, the transfer capacity of the main pump driven by the electric motor is set so that the amount of cooling water required by the engine can be transferred, and the sub pump is set to a capacity that can transfer the priming water when starting the main pump. Is done. While supplying an appropriate amount of cooling water by managing the cylinder wall temperature, the casing at the bottom of the outboard motor that houses the sub pump can be reduced in size, reducing water resistance during cruising and improving the efficiency of the outboard motor. improves.

1 is a left side view illustrating a schematic configuration example of an outboard motor according to the present invention. It is a left view which shows the structural example around the cooling water path of the cooling device which concerns on this invention. (A) which shows the structural example of the main pump in the cooling device which concerns on this invention is a top view, (B) is sectional drawing which follows the II line | wire of (A). (A) which shows the structural example of the subpump in the cooling device which concerns on this invention is a top view, (B) is sectional drawing which follows the II-II line of (A). It is a block diagram which shows the example of a structure around the cooling water channel of the cooling device which concerns on this invention, and its modification, respectively.

Hereinafter, preferred embodiments of the cooling apparatus for an outboard motor according to the present invention will be described with reference to the drawings.
FIG. 1 is a left side view showing a schematic configuration example of an outboard motor 10 according to the present invention. In this case, the outboard motor 10 is fixed to the rear plate P of the hull of the ship on the front side as shown. In the following description, the front of the outboard motor 10 is indicated by an arrow Fr, the rear is indicated by an arrow Rr, and the right side of the outboard motor 10 is indicated by an arrow R as needed. The left side is indicated by an arrow L.

  In the overall configuration of the outboard motor 10, an engine unit or power unit 11, a mid unit 12 and a lower unit 13 are sequentially arranged from the upper part to the lower part, and these units are integrally configured. In the engine unit 11, the engine 14 is mounted and supported vertically through an engine base or an engine holder so that the crankshaft 15 faces the vertical direction. As the engine 14, for example, a V-type multi-cylinder engine or the like can be employed. The mid unit 12 is supported via an upper mount 16 and a lower mount 17 so as to be integrally rotatable around a support shaft 19 (steering shaft) set on the swivel bracket 18. Clamp brackets 20 are provided on the left and right sides of the swivel bracket 18, and are fixed to the rear plate P of the hull via the clamp brackets 20. The swivel bracket 18 is supported so as to be rotatable in the vertical direction around a support shaft 21 (tilt shaft) set in the horizontal direction.

  Referring also to FIG. 2, in the mid unit 12, a drive shaft 22 connected to the lower end portion of the crankshaft 15 is vertically penetrated and the driving force of the drive shaft 22 is described later in the gear case of the lower unit 13. It is transmitted to the propeller shaft. On the front side of the drive shaft 22, a shift rod 23 for performing forward / reverse switching or the like is arranged in parallel in the vertical direction. The mid unit 12 has a drive shaft housing that houses the drive shaft 22.

  The lower unit 13 includes a gear case 25 including a plurality of gears that rotate the propeller 24 by the driving force of the drive shaft 22. The drive shaft 22 extending downward from the mid unit 12 causes the gear attached to itself to mesh with the gear in the gear case 25 to eventually rotate the propeller 24. The power transmission path of the gear device is switched, that is, shifted. Further, the integrally formed casing 26 (which is a lower case in the present embodiment) has an anti-splash plate 27 and an anti-cavitation plate 28 that are arranged vertically near the mating surface with the mid unit 12, below these. A gear case 25 is disposed in a lower part of the casing 26 extending to the front and rear so as to exhibit a bullet shape or a bullet shape in the front-rear direction.

  The shift rod 23 is vertically inserted and supported on the shell-shaped tip end side of the gear case 25 in the casing 26. The shift rod 23 is suspended from the propeller shaft 29 to a position intersecting with the axial extension line. Further, the drive shaft 22 is inserted and supported near the substantially central portion of the casing 26 in the front-rear direction. In the gear case 25, the propeller shaft 29 is disposed along the front-rear direction and is rotatably supported via a plurality of bearings. A drive gear 30 is attached to the lower end portion of the drive shaft 22, and a pair of front and rear forward gears 31 and a reverse (reverse) gear 32 that mesh with the drive gear 30 are rotatably supported on the propeller shaft 29. The

  A power transmission path from the forward gear 31 or the reverse gear 32 to the propeller shaft 29 is formed by a shift operation via the shift rod 23. When the engine 14 is started, the output torque is transmitted from the drive shaft 22 to the propulsion device. That is, the propeller shaft 29 and the propeller 24 are rotated via the forward gear 31 or the reverse gear 32, and the outboard motor 10 generates a propulsive force. Therefore, the hull carrying the propulsion moves forward or backward.

Next, the outboard motor cooling device of the present invention will be described. The cooling device of the present invention takes in water from the water outside the outboard motor 10 by the cooling water pump and supplies the cooling water to the engine unit 11 side. First, the engine is related to the cooling device of this embodiment. A specific configuration example around the unit 11 will be described. In addition, illustration of each structural member is abbreviate | omitted here.
The engine 14 is, for example, a water-cooled four-cycle V-type six-cylinder engine configured by combining a cylinder head 33, a cylinder block 34, a crankcase 35, and the like as schematically illustrated in FIG. By arranging the cylinder block 34 in a V shape in plan view, a V bank is formed between the cylinder blocks 34. A left and right integrated cylinder block 34 is disposed in a V-shape extending in the width direction of the outboard motor 10 behind the crankcase 35 disposed in the foremost portion of the engine 14.

  In each cylinder block 34 of the V bank, three cylindrical sleeves (cylinders) are formed so as to be substantially horizontally arranged in three upper and lower stages, and in each sleeve, a piston 36 (see FIG. 1; 2 in FIG. 1). Two pistons 36 are shown)) are accommodated slidably in the axial direction on the axis of the sleeve. The crankshaft 15 is disposed substantially vertically on the joint surface between the crankcase 35 and the cylinder block 34, and the crankshaft 15 and the piston 36 are connected by a connecting rod 37. Thereby, the reciprocating stroke of the piston 36 is converted into the rotational motion of the crankshaft 15.

  The cylinder head 33 is formed with a combustion chamber aligned with each sleeve, and a spark plug is attached from the outside. An intake port and an exhaust port communicating with the combustion chamber are formed in the cylinder head 33. The exhaust port is connected to an exhaust passage formed outside the left and right cylinder blocks 34 in the width direction, and the intake port extends inward of the V bank.

  In the engine 14, water jackets for circulating cooling water are formed around portions requiring cooling, that is, around the combustion chamber of the cylinder head 33, around the sleeve of the cylinder block 34 and around the exhaust passage. These water jackets communicate with each other so as to form a predetermined cooling water passage, and cooling water is supplied to the cooling water passage by a cooling water pump, which will be described later, and is circulated to cool the engine 14. Yes.

  In the cooling device of the present invention, the cooling water pump that supplies the cooling water to the cooling water passage includes a main pump 38 disposed on the upper portion of the outboard motor 10 as shown in FIG. In this example, it is constituted by a sub pump 39 disposed in a lower case provided with a main water intake port 40 and a sub water intake port 41. Although a specific configuration of the main pump 38 will be described later, the engine unit 11 at the upper part of the outboard motor 10 can be disposed at an appropriate position using an engine holder that supports the engine 14 from below. Specifically, a main pump 38 is disposed below the cylinder head 33 and in the vicinity of the cylinder block 34. The sub pump 39 is disposed in the casing 26 of the lower unit 13 which is a lower case. In this way, one main pump 38 is at the upper part of the outboard motor 10, and the other sub pump 39 is at the lower part of the outboard motor 10, so that the two main pumps 38 and the sub pump 39 are vertically separated in the outboard motor 10. It is an arrangement configuration.

  The main pump 38 is disposed at the upper portion of the outboard motor 10 as described above. The main intake port 40 opened near the lower front side of the casing 26 and the water jacket 42 described above for the engine unit 11 (see FIG. 2). In addition, it arrange | positions in the main cooling water channel | path 43 which connects the detailed illustration abbreviate | omitting in FIG. The sub pump 39 is disposed in a bypass passage 44 formed so as to bypass a part of the main cooling water passage 43 (the main cooling water passage 43A on the water absorption side) on the water absorption side of the main pump 38. As shown in FIG. 2, the bypass passage 44 is arranged in front of the drive shaft 22 and in parallel, that is, in the vertical direction, and the lower end on the water absorption side is connected to the dedicated sub intake 41. The bypass passage 44 on the discharge side of the sub pump 39 is connected to the main cooling water passage 43A in the vicinity of the upper portion of the casing 26 as shown in FIG. In this case, the main water intake 40 and the sub water intake 41 are set below the draft line W (refer FIG. 1) in which the said ship is stopping.

  Here, the cooling water transfer (or discharge) capacity per unit time of the sub pump 39 is set to be smaller than that of the main pump 38. In this case, in this embodiment, the main pump 38 is formed by a non-volumetric centrifugal pump, while the sub pump 39 is formed by a volumetric vane pump. The transfer capacity of the main pump 38 is set so that the amount of cooling water required by the engine 14 can be transferred, and the auxiliary pump 39 is set to a transfer capacity that can supply at least the priming water required when starting the main pump 38. . The arrangement configuration of the main pump 38 and the sub pump 39 is optimized in relation to the transfer capacity, mechanical loss, etc., depending on whether the pump type is a positive displacement type.

  Specifically, as shown in FIG. 3, the main pump 38 has impellers 47 that are radially attached to the rotary shaft 46 in the casing 45. When the impeller 47 rotates, water sucked from the suction port 48 is discharged from the discharge port 49. The upper end of the main cooling water passage 43 </ b> A is connected to the suction port 48, and the discharge port 49 is connected to the water jacket 42.

  As shown in FIG. 4, the sub pump 39 accommodates an impeller 51 attached to the rotating shaft in an eccentric manner in the casing 50. The impeller 51 is formed of an elastic material such as rubber. As the impeller 51 rotates, the water sucked from the suction port 52 is discharged from the discharge port 53. The suction port 52 is connected to the upper end of the suction-side bypass passage 44A.

Further, regarding the drive system of the main pump 38 and the sub pump 39, the main pump 38 is driven by an electric motor, and the sub pump 39 is driven by the drive shaft 22 that transmits the driving force of the engine 14 to the propeller shaft 29 in the casing 26. To do.
As shown in FIG. 2, an electric motor 54 for driving is integrally coupled to the main pump 38, and the rotating shaft 46 connected to the output shaft is rotated by the driving force of the electric motor 54. As a driving power source for the electric motor 54, for example, a battery mounted on the hull side can be used as the power source. In this case, the cylinder wall temperature of the engine 14 around the cylinder head 33 and the cylinder block 34 can be detected by a temperature sensor, and the electric motor 54 can be driven and controlled by the system control unit based on the detection signal.

  Further, in the auxiliary pump 39, the drive shaft 22 is disposed through the casing 50 as shown in FIG. An impeller 51 is attached and fixed around the drive shaft 22, and the impeller 51 also rotates as the drive shaft 22 rotates. Therefore, when the drive shaft 22, that is, the engine 14 is operated, the auxiliary pump 39 is driven in synchronism with this.

In the above case, the cooling water that has circulated through the water jacket 42 and cooled around the engine 14 is finally discharged to the outside of the outboard motor 10 from the drain port 55 (see FIGS. 5A and 5B). It has become.
In addition, a water inspection port is provided for confirming whether the cooling water normally circulates in the cooling water passage from the drained state. In this example, as shown in FIG. 5 (A), a water inspection port 56 connected to the main cooling water passage 43 side on the discharge side of the main pump 38 is provided.

  In the cooling device of the present invention, when the engine 14 is started, the drive shaft 22 rotates at the same time, whereby the auxiliary pump 39 is operated. By operating the sub pump 39, external water (seawater, lake water, river water, etc.) is pumped up as cooling water from the water intake 41. The pumped cooling water is supplied from the bypass passage 44 to the main pump 38 via the main cooling water passage 43A. The cooling water supplied to the main pump 38 acts as the priming water, so that the main pump 38 can be operated at any time.

  In the present invention, in particular, the electric motor 54 is driven according to the cylinder wall temperature at that time. When the electric motor 54 is driven, cooling water is supplied to the water jacket 42 by operating the main pump 38. That is, the supply of cooling water can be controlled by temperature management of the cylinder wall temperature, and can be appropriately supplied so that the amount of cooling water required by the engine 14 is obtained.

  Conventionally, for example, a positive displacement pump driven by a drive shaft is used, and a thermostat is provided virtually as shown in FIG. 5A, and the flow rate of cooling water is adjusted by controlling the water temperature of the thermostat. It was. In other words, when the engine block is idling or when the outside air temperature is low, when the cylinder block is cooled, the temperature of the engine becomes too low, and the viscosity of the lubricating oil increases. In such a case, the cooling water is not drained until the temperature reaches a predetermined temperature, that is, the cooling water is not circulated. In the present invention, regardless of the driving state of the engine 14, the electric motor 54 is controlled to be turned on / off according to the cylinder wall temperature so that the flow rate of the cooling water can be adjusted. As a result, the thermostat as shown in FIG. 5A can be eliminated, and the water pressure valve and the like shown in FIG. 5A can also be eliminated.

  Further, in the present invention, the transfer capacity of the main pump 38 is set so that the amount of cooling water required by the engine 14 can be transferred, and the sub pump 39 is set to a capacity that can transfer the priming water when starting the main pump 38. . Although the sub pump 39 is a positive displacement vane pump, it is possible to use a small pump by minimizing the capacity thereof. As a result, the casing 26 at the lower part of the outboard motor 10 that houses the sub pump 39 can be reduced in size, the water resistance during cruising is reduced, and the efficiency of the outboard motor 10 is improved.

  In addition, since the large-capacity main pump 38 is a spiral pump, the mechanical loss of the cooling water pump is greatly reduced as compared with a conventional outboard motor in which all the cooling water is transferred by the vane pump. be able to. By reducing the size of the auxiliary pump 39 to such an extent that the priming water for the main pump 38 can be supplied, in addition to the effect of reducing the mechanical loss, the degree of wear and consumption of the impeller 51 and further the exchange thereof are suppressed as much as possible. Durability can be greatly increased.

  Further, since the centrifugal pump forming the main pump 38 has a weak suction force compared to a vane pump or the like, it is necessary to fill the pump chamber and the suction passage with water in order to activate the centrifugal pump. The sub pump 39 functioning as the other “priming water pump” is constituted by a vane pump having a strong suction force, so that even if the sub pump 39 is disposed at a position higher than the draft surface W, water is surely supplied from the sub water intake 41. Can be imported. This makes it possible to reduce the size of the casing 26 buried in the water in combination with the miniaturization of the sub pump 39 itself, reducing water resistance during cruising, and improving the efficiency of the outboard motor 10 in this respect as well. To do.

  Further, by arranging the main pump 38 on the upper portion of the outboard motor 10 using an engine holder or the like, the casing 26 at the lower portion of the outboard motor 10 can be reduced in size, and also in this case, water resistance is reduced. Thus, the efficiency of the outboard motor 10 is improved. In this case, since the electric motor 54 for driving the main pump 38 can be disposed at a high position away from the water surface, the electric motor 54 is prevented from getting wet and the durability of the electric motor 54 is improved.

  Here, in the modification of the present invention, as shown in FIG. 5B, the bypass passage 44A on the suction side of the sub pump 39 is connected to the main water intake 40, and in this example, the sub pump 39 is a dedicated water intake. Does not have. Further, a check valve 57 is provided in the main cooling water passage 43 </ b> A below the draft line W to prevent the backflow of the cooling water to the main water intake 40 side.

  Also in this case, the operation of the electric motor 54 is controlled according to the cylinder wall temperature, and the flow rate of the cooling water can be adjusted by the main pump 38. A thermostat, a water pressure valve, etc. as shown in FIG. 5B can also be eliminated. By having only a single main water intake 40, there is an advantage that the configuration can be simplified.

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.
In the above-described embodiment, an example in which the engine 14 is a V-type six-cylinder engine has been described.

10 Outboard Motor, 11 Engine (Power) Unit, 12 Mid Unit, 13 Lower Unit, 14 Engine, 15 Crankshaft, 16 Upper Mount, 17 Lower Mount, 18 Swivel Bracket, 19, 21 Spindle, 20 Clamp Bracket, 22 Drive shaft, 23 Shift rod, 24 Propeller, 25 Gear case, 26 Casing 26 (lower case), 27 Anti-splash plate, 28 Anti-cavitation plate, 29 Propeller shaft, 30 Drive gear, 31 Forward (forward) gear, 32 Reverse (reverse) Gear, 33 Cylinder head, 34 Cylinder block, 35 Crankcase, 36 Piston, 37 Connecting rod, 38 Main pump, 39 Sub pump, 40 Main intake port, 41 Intake port, 42 Water jacket, 43 Main cooling water passage, 44 Bypass passage, 45 Casing, 46 Rotating shaft, 47 Impeller, 48 Inlet port, 49 Outlet port, 50 Casing, 51 Impeller, 52 Inlet port, 53 Outlet port, 54 Electric motor, 55 drainage port, 56 water inspection port, 57 check valve, P tail plate.

Claims (5)

A cooling device for an outboard motor that takes in water from outside the outboard motor by a cooling water pump and supplies cooling water to the engine unit side.
The cooling water pump is composed of a main pump disposed in the upper portion of the outboard motor and a sub pump disposed in the lower case provided in the lower portion of the outboard motor and having a water intake.
The main pump is disposed in a main cooling water passage that connects the water intake of the lower case and a water jacket of the engine unit,
The sub pump is disposed in a bypass passage formed so as to bypass a part of the main cooling water passage on the water absorption side of the main pump,
The cooling water transfer capacity per unit time of the sub pump is set smaller than that of the main pump ,
A cooling device for an outboard motor , wherein the cooling water transfer capability of the sub pump is set to a capacity capable of transferring priming water when starting the main pump . 2. The outboard motor cooling device according to claim 1, wherein the main pump is formed by a non-volumetric centrifugal pump, and the sub pump is formed by a volumetric vane pump. The outboard motor cooling device according to claim 1 or 2, wherein a water absorption side of the sub pump of the bypass passage is connected to the main cooling water passage below a water line where the ship is stopped. 4. A check valve for preventing a reverse flow of cooling water to the intake port side is provided in the main cooling water passage below the water line where the ship is stopped. The outboard motor cooling apparatus according to Item 1. The main pump is driven by an electric motor capable of adjusting a flow rate of cooling water according to a cylinder wall temperature, and the sub pump is driven by a drive shaft that transmits an engine driving force to a propeller shaft of the lower case. Item 5. The outboard motor cooling device according to any one of Items 1 to 4.

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