JP6207082B2 - Power unit - Google Patents

Description

  The present invention relates to a power unit including a scavenging pump that sucks oil from a specific space in a power unit case to another part.

  A power unit in which an engine and a transmission are integrated is used as a drive unit of a vehicle. As this type of power unit, one having a structure in which oil that has flowed into a specific space in the power unit case is sucked into the oil reservoir by a scavenging pump is known (for example, see Patent Document 1).

  In the power unit described in Patent Document 1, the inside of the power unit case is divided into a low liquid level chamber (specific space) where the oil level of the oil is desired to be lowered and an oil storage part for storing the oil, and scavenging. The pump is installed at a position lower than the liquid level in the oil storage chamber. A suction passage extending upward from the low liquid level chamber is connected to the suction portion of the scavenging pump, and a strainer is provided at the suction port of the suction passage facing the low liquid level chamber. The shaft portion of the scavenging pump is configured as a common shaft with the shaft portion of the adjacent lubricating oil pump, and the end portion of the shaft portion is immersed in the oil in the oil storage portion.

JP2013-257018A

  In the case of the above power unit, while the scavenging pump is being driven, the oil is sucked into the oil reservoir from the low liquid level chamber, but when the operation of the scavenging pump has been stopped for a long time, There is concern about the oil going back into the low liquid chamber. This reversal of oil is caused by the high-level oil in the oil reservoir passing through the peripheral area of the scavenging pump shaft at a lower position and passing through the suction passage connected to the scavenging pump. It is thought that it flows in. If the oil returns to the low liquid level chamber when the scavenging pump is stopped in this way, there is a disadvantage that it takes time to lower the oil level in the low liquid level chamber when the scavenging pump is restarted.

  Therefore, the present invention is intended to provide a power unit capable of suppressing the backflow of oil from the oil reservoir to the low liquid level chamber even when the scavenging pump is stopped for a long time.

  In order to solve the above problems, a power unit according to an aspect of the present invention includes an oil reservoir (29) provided in a power unit case (UC) and the oil reservoir (29) in the power unit case (UC). ) And a low liquid level chamber (28) provided separately from the oil reservoir (29), and separates the oil in the low liquid level chamber (28) from the power unit case (UC). A scavenging pump (32) that sucks up to the part of the pump, and a suction port (61) arranged on one end side opens into the low liquid level chamber (28), and the other end is connected to the suction part of the scavenging pump (32). A suction passage (60) to be connected, wherein the shaft (20a) of the scavenging pump (32) is higher than the suction port (61) of the suction passage (60), and the oil The power unit is disposed at a position lower than the level of oil in contact with the reservoir (29), and the suction passage (60) is higher than the level of oil in the oil reservoir (29). Also has a bent portion (74) positioned above, the suction port (61) is provided on one end side of the bent portion (74), and the scavenging pump on the other end side of the bent portion (74). The suction part (32) is connected.

  Thereby, when the scavenging pump (32) is driven, the oil in the low liquid level chamber (28) in the power unit case (UC) is sucked into the scavenging pump (32) through the suction passage, and the scavenging pump (32 32) is discharged to another part in the power unit case (UC). At this time, since the suction force of the scavenging pump (32) acts on the suction passage (60), the oil passes through the bent portion (74) and is introduced into the scavenging pump (32). On the other hand, when the drive of the scavenging pump (32) is stopped, the shaft portion of the scavenging pump (32) in which the oil in the oil reservoir (29) is lower than the oil reservoir (29). The oil is stored in the oil reservoir (29) in the suction passage (60) connected to the suction part of the scavenging pump (32). Since the bent portion (74) positioned above the surface height is provided, the oil in the scavenging pump (32) gets over the bent portion (74) of the suction passage (60) to reach the low liquid level chamber ( 28) It becomes difficult to flow in.

  In the power unit case (UC), a crankshaft (15) of the engine (11) and hydraulic clutches (50A, 50B) for connecting and disconnecting power below the crankshaft (15) are disposed. A clutch chamber (28) may be provided around the hydraulic clutch (50A, 50B) so as to be separated from the oil reservoir (29), and the clutch chamber (28) may be the low liquid level chamber.

  In this case, even when the hydraulic clutch (50A, 50B) has to be arranged at a low position in the power unit case (UC), the oil in the clutch chamber (28) is removed by the scavenging pump (32). Since it can be sucked into (29), the rise of the oil level in the clutch chamber (28) can be suppressed. Thereby, it is possible to suppress an increase in rotational resistance due to oil when the hydraulic clutch (50A, 50B) rotates or operates. In addition, when the scavenging pump (32) is stopped, it is difficult for oil to flow back from the oil reservoir (29) to the low liquid level chamber (28), so that the hydraulic clutch (50A, 50B) is immersed as much as possible when starting the engine. Can be suppressed. Therefore, the startability of the engine can be improved.

  The oil storage section (29) includes an operation oil storage chamber (33) for storing oil that operates the hydraulic clutch (50A, 50B), and an oil storage chamber (33) separate from the operation oil storage chamber (33). 34), and the scavenging pump (32) and the operating oil pump (30) for pumping oil for operating the hydraulic clutch (50A, 50B) share the drive system and operate The scavenging pump (32) is coaxially provided in the oil storage chamber (33), and the scavenging pump (32) causes the oil sucked up from the clutch chamber (28) to flow into the other oil storage chamber (34). Also good.

  In this case, since the scavenging pump (32) and the operating oil pump (30) share the drive system and are provided coaxially in the operating oil storage chamber (33), the scavenging pump (32) and the operating oil pump (30) are operated. The oil pump (30) can be compactly arranged in the power unit case (UC). Further, the oil sucked up from the low liquid level chamber (28) by the scavenging pump (32) does not flow directly into the operating oil storage chamber (33), but is stored separately from the operating oil storage chamber (33). Since the oil flows into the chamber (34), it is possible to prevent the oil in the working oil storage chamber (33) from being stirred. That is, since the oil level from the scavenging pump (32) is low in the oil level in the low level chamber (28), the oil in the inflow portion may be agitated by air entrainment or the like. . However, in this power unit, oil discharge from the scavenging pump (32) does not flow directly into the working oil storage chamber (33), so that the oil is stirred in the working oil storage chamber (33). It can be prevented in advance.

  Further, a lubricating oil pump (31) for lubricating movable parts in the power unit case (UC) is provided, and the scavenging pump (32), the operating oil pump (30), and the lubricating oil pump ( 31) is configured as an integral pump unit (20) sharing a drive system, and an end wall (70B) is provided on one end side in the axial direction of the pump unit (20), and the power unit case The case part (12L) constituting the (UC) is provided with a main partition wall (26) separating the inside of the power unit case (UC) into the clutch chamber (28) and the oil reservoir (29), A sub-partition wall (27) is provided in the oil reservoir (29) to separate the working oil reservoir (33) and the separate oil reservoir (34). The main partition wall (26) is provided with an opening (66) communicating with the working oil storage chamber (33), and the working oil storage chamber (33) has a main opening of the pump unit (20). May be inserted from the other end of the pump unit (20), and the end wall (70B) of the pump unit (20) may be coupled to the peripheral edge of the opening (66). .

In this case, an operating oil storage chamber (33) is formed on the case part (12L) of the power unit case (UC) by the main partition wall (26) and the sub partition wall (27), and the main partition wall (26). ) Is provided with an opening (66) communicating with the working oil storage chamber (33), so that the case part (12L) integrally including the working oil storage chamber (33) can be easily formed by casting. Can do. That is, when casting the case part (12L), the mold can be easily pulled out from the concave space inside the working oil storage chamber (33) through the opening (66) of the main partition wall (26).
The scavenging pump (32), the operating oil pump (30), and the lubricating oil pump (31) share a drive system and are configured as an integrated pump unit (20), and the pump unit (20) Since it is provided coaxially in the operating oil reservoir (33), a plurality of pumps can be compactly arranged in the power unit case (UC).
Further, the pump unit (20) is simply inserted into the working oil reservoir (33) through the opening (66) and the end wall (70B) is connected to the peripheral edge of the opening (66). It can be easily installed in the oil storage chamber (33) for operation.

  According to this invention, the scavenging pump is connected to the suction part of the scavenging pump, since the bent top part is provided above the liquid level of the oil in the oil storage part. Even when the pump is stopped for a long time, the oil in the oil reservoir can be prevented from flowing back into the low liquid level chamber via the scavenging pump and the suction passage.

1 is a left side view of a motorcycle according to an embodiment of the present invention. It is a rear view of the power unit which concerns on embodiment of this invention. It is a top view of the power unit which concerns on embodiment of this invention. It is a left view of the power unit which concerns on embodiment of this invention. It is a figure corresponding to the VV cross section of FIG. 3 of the power unit which concerns on embodiment of this invention. It is the figure which expanded and showed a part of FIG. 5 of the power unit which concerns on embodiment of this invention. It is a figure which shows typically the oil supply system of the power unit which concerns on embodiment of this invention. It is a perspective view which shows the component of the power unit case which concerns on embodiment of this invention. It is a side view of the pump unit built in the power unit which concerns on embodiment of this invention. It is a rear view of the pump unit incorporated in the power unit which concerns on embodiment of this invention. It is the front view which made some cross sections the pump unit incorporated in the power unit which concerns on embodiment of this invention. It is a cross section corresponding to the XII-XII cross section of FIG. 10 of the pump unit built in the power unit which concerns on embodiment of this invention. It is a cross section corresponding to a XIII-XIII cross section of Drawing 10 of a pump unit built in a power unit concerning an embodiment of this invention. It is a cross section corresponding to the XIV-XIV cross section of FIG. 10 of the pump unit built in the power unit which concerns on embodiment of this invention. It is a cross section corresponding to the XV-XV cross section of FIG. 10 of the pump unit built in the power unit which concerns on embodiment of this invention. It is a longitudinal cross-sectional view of the hydraulic control apparatus incorporated in the power unit which concerns on embodiment of this invention.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the directions such as front, rear, left and right in the following description are the same as those in the vehicle described below unless otherwise specified. Further, in the drawings used for the following explanation, an arrow FR indicating the front of the vehicle, an arrow LH indicating the left side of the vehicle, and an arrow UP indicating the upper side of the vehicle are shown.

FIG. 1 is a diagram showing a left side surface of a motorcycle 1 that employs a power unit PU according to this embodiment.
In the motorcycle 1 shown in the figure, the front wheel 2 is pivotally supported at the lower ends of a pair of left and right front forks 3, and the upper part of the left and right front forks 3 is connected to a head pipe 6 at the front end of a vehicle body frame 5 via a steering stem 4. It is pivotally supported to steer. A steering wheel 4a for steering the front wheels is attached to the upper portion of the steering stem 4.

  A pair of left and right main frames 7 extend obliquely downward and rearward from the head pipe 6, and upper ends of pivot frames 8 are connected to rear ends of the left and right main frames 7, respectively. A power unit PU including a horizontally opposed 6-cylinder engine 11 and a multistage transmission 25 is mounted below the left and right main frames 7 and in front of the left and right pivot frames 8.

  A front end portion of a swing arm 10 that pivotally supports the rear wheel 9 is pivotally supported on the left and right pivot frames 8 so as to be vertically swingable. The swing arm 10 is a cantilever type in which a rear wheel 9 is pivotally supported at a rear end portion of a hollow right arm. A drive shaft (not shown) extending from the transmission 25 of the power unit PU is inserted into the right arm of the swing arm 10, and power is transmitted between the power unit PU and the rear wheel 9 via a transmission system including the drive shaft. Has been made.

2 is a view of the power unit PU as viewed from the rear side, and FIGS. 3 and 4 are views of the power unit PU as viewed from the upper side and the left side. FIG. 5 is a view corresponding to the VV cross section of FIG. 3 of the power unit PU, and FIG. 6 is an enlarged view of a part of FIG.
As shown in these drawings, the power unit PU of this embodiment is provided with a left cylinder portion 13L and a right cylinder portion 13R protruding substantially horizontally on both the left and right sides of the upper portion of the crankcase 12. The left cylinder portion 13L and the right cylinder portion 13R are provided with three cylinders arranged in the front-rear direction. The crankcase 12 is composed of two blocks divided at the center in the left-right direction. Hereinafter, the left block of the crankcase 12 is referred to as a left case half 12L, and the right block is referred to as a right case half 12R.
A front crank cover 49 is fastened and fixed to the front end face of the crankcase 12, and a rear crank cover 48 is fastened and fixed to the rear end face of the crankcase 12. In addition, an opening (not shown) is provided at the center near the lower portion of the rear crank cover 48, and the opening is closed by a clutch cover 47 that bulges like a bowl toward the rear side of the vehicle body.
In this embodiment, the power unit case UC includes the crankcase 12, the left cylinder portion 13L and the right cylinder portion 13R, the front crank cover 49, the rear crank cover 48, the clutch cover 47, and the like.

  The power unit PU includes a crankshaft 15 of the engine 11 along the vehicle front-rear direction, a main shaft 16 of the transmission 25 disposed in parallel with the crankshaft 15 below the crankshaft 15, and a right side of the main shaft 16. The counter shaft 17 of the transmission 25 disposed in parallel with the main shaft 16, the output shaft 18 disposed in the upper right of the counter shaft 17 in parallel with the counter shaft 17, and the crank shaft 15 on the left of the crank shaft 15 And a generator shaft 19 arranged in parallel. For the crankcase 12, the extending direction of the crankshaft 15 and the main shaft 16 is referred to as an axial direction unless otherwise specified.

  A piston (not shown) accommodated in the left cylinder part 13L and the right cylinder part 13R so as to reciprocate is connected to the crankshaft 15 via a connecting rod (not shown). The crankshaft 15 converts the linear motion of the piston accompanying the combustion of gasoline into a rotational motion and outputs it to the outside.

  The main shaft 16 and the counter shaft 17 are provided with a plurality of gear trains that can establish selective power transmission with different gear ratios. The combination of the gear elements of the gear train is appropriately performed by a shift operation by the driver. Further, the output shaft 18 of the transmission 25 protrudes from the rear portion of the crankcase 12 toward the rear side of the vehicle body. The output shaft 18 rotates upon receiving power from the counter shaft 17 and transmits the rotation to the rear wheel 9 via a power transmission system such as a drive shaft.

  As shown in FIG. 5, a primary drive gear 51 is attached to the rear end side of the crankshaft 15, and a twin type clutch device having a pair of hydraulic clutches 50 </ b> A and 50 </ b> B on the rear end side of the main shaft 16 ( DCT) 50 is attached. Although not shown in detail in the main shaft 16 of this embodiment, a first shaft that holds gears corresponding to odd-numbered shift stages, and a second shaft that holds gears corresponding to even-numbered shift stages, and have. A primary driven gear 52 that meshes with the primary drive gear 51 on the crankshaft 15 side is attached to the power input portion of the clutch device 50. The hydraulic clutches 50A and 50B before and after the clutch device 50 selectively connect the primary driven gear 52 to the first shaft and the second shaft according to the speed change of the transmission 25. Each of the hydraulic clutches 50A and 50B is controlled by a hydraulic pressure adjusted based on a control signal from a controller (not shown). The hydraulic clutches 50A and 50B are disposed in a lower region in the power unit case UC below the crankshaft 15.

  A pump unit 20 in which a plurality of pumps, which will be described later, are integrated, is disposed at the lower left of the left case half 12L of the crankcase 12. As shown in FIG. 5, the pump unit 20 has a common shaft portion 20a, and a pump gear 21 is integrally attached to one end of the shaft portion 20a. Further, the pump drive gear 22 is connected to the primary driven gear 52 so as to be integrally rotatable, and a transmission chain 23 is stretched between the pump drive gear 22 and the pump gear 21. The rotation of the primary driven gear 52 (rotation of the crankshaft 15) is transmitted to the shaft portion 20a of the pump unit 20 via the pump gear 21, the transmission chain 23, and the pump drive gear 22.

  Here, at the rear part of the crankcase 12, there is a rear partition wall 26 (mainly divided into a main space part in the crankcase 12 and a space part that mainly accommodates the hydraulic clutches 50A and 50B in the rear part of the crankcase 12. Partition wall) is formed. The rear partition wall 26 is formed across the left case half body 12L and the right case half body 12R of the crankcase 12. Further, a peripheral wall 27 protruding rearward from the rear partition wall 26 is formed at the rear end portion of the crankcase 12, and a rear crank cover 48 is abutted and fastened to the peripheral wall. In the rear space of the crankcase 12 sandwiched between the rear partition wall 26 and the rear crank cover 48, a primary drive gear 51, a primary driven gear 52, a pump drive gear 22, a pump gear 21 and the like are arranged in addition to the hydraulic clutches 50A and 50B. Is done. This space constitutes the clutch chamber 28 in this embodiment.

  In addition, parts around the crankshaft 15 of the engine 11 and a gear group of the transmission 25 are arranged in a main space in the crankcase 12 separated by the rear partition wall 26, and the pump unit 20 described above is also included. The main part is also arranged. A lower region of the space portion is an oil storage portion 29 in which oil used for lubricating the engine 11 and the transmission 25, operating the hydraulic clutches 50A and 50B, and the like is stored. Therefore, the rear partition wall 26 at the rear portion of the crankcase 12 divides the power unit case UC into an oil storage portion 29 and a clutch chamber 28.

  By the way, the above-described pump unit 20 includes an operating oil pump 30 for pumping oil to the hydraulic clutches 50A and 50B, and a lubricating oil pump 31 for pumping oil for lubricating each part of the engine 11 and the transmission 25. And a scavenging pump 32 that sucks oil that has flowed into the clutch chamber 28 into the oil reservoir 29. The scavenging pump 32 draws oil from the bottom side of the clutch chamber 28 to the oil reservoir 29 to lower the oil level in the clutch chamber 28, so that the hydraulic clutches 50 </ b> A and 50 </ b> B are immersed in the oil. Thus, the increase of the operating resistance of the hydraulic clutches 50A, 50A is suppressed.

FIG. 7 is a diagram showing a schematic configuration of an oil supply system in the power unit PU according to this embodiment.
As shown in the figure, the oil supply system of the power unit PU is roughly divided into three oil supply systems, that is, an operation oil supply system, a lubrication oil supply system, and a scavenging oil supply system. These three oil supply systems are driven by using three oil pumps (the operating oil pump 30, the lubricating oil pump 31, and the scavenging pump 32) in the pump unit 20 as hydraulic supply sources, respectively.

  Hereinafter, the overall structure of the oil supply system in the power unit PU will be described with reference to FIG. As described above, the power unit casing UC is divided into the oil reservoir 29 and the clutch chamber 28 by the rear partition wall 26. The bottom of the oil reservoir 29 is provided with a substantially sealed space surrounded by the peripheral wall 35 and the top wall 36, and the inner space stores oil mainly used in the operating oil supply system. It is set as the oil storage chamber 33 for operation. In addition, the space outside the operating oil reservoir 33 in the bottom region in the oil reservoir 29 is a lubricating oil reservoir 34 that stores oil mainly used in the lubricating oil supply system.

  The upper wall 36 of the working oil storage chamber 33 has a lower wall 36a and a higher wall 36b that is higher than the lower wall 36a. The oil in the working oil storage chamber 33 is placed outside the lower wall 36a. A communication hole 37 is formed to flow out into the lubricating oil storage chamber 34. The communication hole 37 stores the oil in the working oil storage chamber 33 for lubricating oil when the liquid level of the oil returned and stored in the working oil storage chamber 33 exceeds a specified height. It functions to overflow into the chamber 34. Oil that overflows from the working oil storage chamber 33 is stored in the lubricating oil storage chamber 34.

  The suction part of the working oil pump 30 communicates with the bottom of the working oil storage chamber 33 via an oil strainer 38. The working oil pump 30 sucks up oil from the working oil storage chamber 33 via the oil strainer 38. On the other hand, the discharge part of the operating oil pump 30 is connected to an operating oil passage 39 connected to the hydraulic clutches 50A and 50B.

  A hydraulic pressure adjusting device 40 for adjusting the pressure of oil supplied to the hydraulic clutches 50A and 50B is interposed in the middle of the operating oil passage 39. In FIG. 7, only one hydraulic pressure adjusting device 40 is shown, but in reality, two hydraulic pressure adjusting devices 40 are provided corresponding to the respective hydraulic clutches 50A and 50B. Further, the operating oil passage 39 downstream of the hydraulic pressure adjusting device 40 is bifurcated and connected to the hydraulic clutches 50A and 50B.

  Although the detailed structure of each hydraulic pressure adjusting device 40 will be described in detail later, the hydraulic pressure adjusting device 40 corresponds to the oil introduction port 41 into which the oil pumped from the operating oil pump 30 is introduced and the oil adjusted to the set hydraulic pressure. A control port 42 that supplies the hydraulic clutch 50A or 50B, and a drain port 43 that discharges excess oil introduced into the oil introduction port 41. The oil discharged from the drain port 43 is returned to the working oil storage chamber 33 through the return passage 44.

  A relief valve 45 for returning excess oil to the working oil storage chamber 33 and a hydraulic sensor 46 as working hydraulic pressure detection means are provided in the vicinity of the discharge portion of the working oil pump 30 in the working oil passage 39. Is provided. The hydraulic sensor 46 outputs a warning signal when the pressure in the working oil passage 39 drops below a predetermined value. Specifically, the hydraulic sensor 46 is connected to an input portion of a controller (not shown), and the controller is configured such that the pressure in the operating oil passage 39 is equal to or less than a predetermined value based on the detection value of the hydraulic sensor 46. When the determination is made, for example, a warning indicator lamp on the display panel is turned on.

  In addition, a liquid level switch 64 that issues a warning signal when the liquid level of the oil in the working oil storage chamber 33 falls below a predetermined height is provided in the working oil storage chamber 33. Specifically, the liquid level switch 64 is turned on when the liquid level of the oil in the working oil storage chamber 33 becomes a predetermined height or less, for example, directly turns on a warning indicator lamp on the display panel.

  A suction passage 54 is connected to the suction portion of the lubricating oil pump 31, and the suction passage 54 passes through the peripheral wall 35 (wall) of the working oil storage chamber 33. An end portion of the suction passage 54 penetrating the peripheral wall 35 communicates with a bottom portion of the lubricating oil storage chamber 34 via an oil strainer 55. The lubricating oil pump 31 sucks up oil from the lubricating oil storage chamber 34 via the oil strainer 55. On the other hand, the discharge portion of the lubrication oil pump 31 is connected to a lubrication oil passage 56 connected to each lubrication required portion of the engine 11 and the transmission 25.

  In the middle of the lubricating oil passage 56, a low pressure hydraulic switch 57 is provided as lubricating oil pressure detecting means. The low pressure hydraulic switch 57 outputs a warning signal when the pressure of the oil supplied from the operating oil passage 39 to the lubrication required portion of the engine 11 or the transmission 25 drops below a predetermined value. Specifically, the low pressure hydraulic switch 57 is turned on when the oil pressure in the working oil passage 39 falls below a predetermined value, for example, directly turns on a warning indicator lamp on the display panel.

  A relief valve 63 for allowing excess oil to flow into the working oil storage chamber 33 is provided in the vicinity of the discharge portion of the lubricating oil pump 31 in the lubricating oil passage 56. Further, part of the oil supplied to the lubricating oil passage 56 actively flows into the working oil storage chamber 33 into the portion of the lubricating oil passage 56 drawn out from the operating oil storage chamber 33 to the outside. The transition passage 58 is connected. Further, a lubricating oil filter 59 for purifying oil is interposed in the lubricating oil passage 56 at a position upstream of the branch connection portion of the transition passage 58.

  A suction passage 60 is connected to the suction portion of the scavenging pump 32, and the suction passage 60 communicates with the bottom of the clutch chamber 28 via an oil strainer 61. The scavenging pump 32 sucks up oil from the bottom of the clutch chamber 28 via the oil strainer 61. On the other hand, the discharge part of the scavenging pump 32 communicates with the lubricating oil storage chamber 34 outside the working oil storage chamber 33 through the discharge passage 62. Therefore, the oil sucked up from the clutch chamber 28 by the scavenging pump 32 flows into the lubricating oil storage chamber 34. In this embodiment, the clutch chamber 28 constitutes a low liquid level chamber in the power unit case UC.

Next, a specific internal structure of the power unit PU will be described.
8 is a view of the left case half body 12L of the crankcase 12 as viewed from the diagonally upper side of the center side in the left-right direction of the crankcase 12, and FIG. 9 is a view of the pump unit 20 as viewed from the side. 10 is a view of the pump unit 20 as viewed from the front side of the vehicle body (a rear view of the pump unit 20). FIG. 11 is a view of the pump unit 20 as seen from the rear side of the vehicle body with a part broken away. It is a front view of the pump unit 20. 12 to 15 are views showing cross sections of respective parts in the power unit PU with the pump unit 20 as the center.
As shown in FIG. 8, a relatively large opening 66 that connects the clutch chamber 28 side and the oil reservoir 29 side is provided at the lower left of the rear partition wall 26 of the left case half 12L. The opening 66 is formed in an irregular trapezoidal shape in which both side walls are gently curved between the journal portion 65 supporting the main shaft 16 and the peripheral wall of the left case half 12L.

  A concave space portion is integrally provided from the opening 66 along the axial direction of the crankcase 12 on the oil reservoir 29 side of the opening 66 of the rear partition wall 26. This concave space is formed by the peripheral wall of the left case half 12L from the left side surface to the bottom surface, and the left case half 12L is formed on the right side surface, the top surface, and the bottom surface (the front surface portion of the vehicle body). A continuous wall is provided between the rear partition wall 26 and the peripheral wall. This space portion constitutes the aforementioned working oil storage chamber 33 (see FIG. 7) in the oil storage portion 29. The upper wall of the space that constitutes the working oil reservoir 33 constitutes the upper wall 36 of the aforementioned working oil reservoir 33, and the right side wall further constitutes the aforementioned working oil reservoir 33. A part of the peripheral wall 35 is configured. Further, the walls constituting the right side surface, the bottom surface portion, and the top surface portion of the space portion (operating oil storage chamber 33) are arranged in the oil storage portion 29 in the operating oil storage chamber 33 and the lubricating oil storage chamber 34 (separate storage). A secondary partition wall that is separated from the chamber).

  The upper wall 36 of the working oil storage chamber 33 is formed in a stepped shape as shown in FIG. 13, and the lower oil wall 36a has lubricating oil inside and outside the working oil storage chamber 33 as described above. A communication hole 37 that communicates with the storage chamber 34 is formed. The above-described liquid level switch 64 is attached to the wall in the working oil storage chamber 33.

  Further, as shown in FIG. 14, a lubricating oil supply pipe 67 protruding into the working oil storage chamber 33 along the axial direction of the crankcase 12 is formed on the wall of the bottom surface portion of the working oil storage chamber 33. It is provided integrally. One end of the supply pipe 67 is connected to the discharge part of the lubricating oil pump 31 in the pump unit 20 in the working oil storage chamber 33, and the other end is outside the working oil storage chamber 33. It is connected to a lubricating oil filter 59. The supply pipe 67 constitutes a part of the lubricating oil passage 56 described above (see FIG. 7). In the case of this embodiment, the lubricating oil filter 59 is attached to the left case half 12L so that a part of the lubricating oil filter 59 is exposed to the outside (FIG. 4 and the like). reference).

  Further, on the wall of the bottom surface portion of the working oil storage chamber 33, as shown in FIGS. 13 and 14, a lubricating oil suction pipe protruding into the working oil storage chamber 33 along the axial direction of the crankcase 12. 68 is provided integrally. One end portion of the suction pipe 68 is connected to the suction portion of the lubricating oil pump 31 in the pump unit 20 in the working oil storage chamber 33, and the other end portion is connected to the outside of the working oil storage chamber 33. An oil strainer 55 is connected to the bottom of the lubricating oil storage chamber 34. The other end of the suction pipe 68 is bent to the right side of the working oil storage chamber 33 and is connected to the oil strainer 55 at a stepped recess 69 provided on the right side wall of the working oil storage chamber 33. . The suction pipe 68 constitutes a part of the suction passage 54 described above (see FIG. 7).

  On the other hand, as shown in FIGS. 9 to 15, the pump unit 20 has two intermediate blocks 70 </ b> C and 70 </ b> D overlapped in the axial direction between a pair of end blocks 70 </ b> A and 70 </ b> B. The unit case 70 is configured by being fastened. In this embodiment, each oil pump (lubricating oil pump 31, operating oil pump 30, and scavenging pump 32) is constituted by a trochoid pump. The lubricating oil pump 31 is disposed between the one end block 70A and the one intermediate block 70C, and the operating oil pump 30 is disposed between the one intermediate block 70C and the other intermediate block 70D. 32 are arranged between the other intermediate block 70D and the other end block 70B, respectively.

  The suction part 31i and the discharge part 31o of the lubricating oil pump 31 protrude outward from the one end block 70A along the axial direction as shown in FIGS. Are connected to a suction pipe 68 and a supply pipe 67 projecting inward from each other. Further, as shown in FIG. 12, a relief valve 63 for controlling the discharge pressure and returning excess oil to the suction side is interposed in the middle of the discharge portion 31o.

  As shown in FIGS. 9, 10 and the like, the suction portion 30i of the operating oil pump 30 extends downward from one intermediate block 70C, and an oil strainer 38 is connected to the lower end thereof. Further, as shown in FIG. 15 and the like, the discharge portion 30o of the operating oil pump 30 penetrates the other intermediate block 70D and the other end block 70B from the one intermediate block 70C, and the other end block 70B. Open to the end face side. The opening penetrating the other end block 70B is connected to the operating oil passage 39 on the rear crank cover 48 side via a connection pipe 72. Further, a relief valve 45 that controls the discharge pressure and returns excess oil to the suction side is interposed in the middle of the discharge unit 30o.

  The suction part and the discharge part of the scavenging pump 32 are respectively connected to a suction passage 60 and a discharge passage 62 formed across the other end block 70B and the other intermediate block 70D.

  The other end block 70B projects radially outward from the block main body portion 70Ba that houses the scavenging pump 32 and the relief valve 45, and the axial end of the block main body portion 70Ba adjacent to the intermediate block 70D. Flange portion 70Bb. The suction passage 60 and the discharge passage 62 are formed across part of the flange portion 70Bb.

  As shown in FIGS. 5 and 6, the outer shape of the flange portion 70 </ b> Bb of the end block 70 </ b> B is formed in a substantially similar shape that is slightly larger than the opening 66 of the left case half 12 </ b> L. The outer edge portion of the flange portion 70Bb is a peripheral portion of the opening 66 of the rear partition wall 26 in a state where the main portion (portion other than the end block 70B) of the pump unit 20 is inserted into the working oil storage chamber 33 through the opening 66. Are fixed by bolt fastening from the outside of the rear partition wall 26 (from the rear side). As a result, the opening 66 of the rear partition wall 26 is closed by the end block 70B, the inside of the working oil storage chamber 33 is substantially sealed, and the working oil storage chamber 33 and the clutch chamber 28 are also partitioned. In this embodiment, the other end block 70 </ b> B is provided on one end side in the axial direction of the pump unit 20 and constitutes an end wall coupled to the peripheral edge of the opening 66.

  Here, as shown in FIG. 11 and the like, the suction passage 60 has an upper flow path 60a that extends obliquely upward from the suction portion of the scavenging pump 32, and changes its direction at the upper end side of the upper flow path 60a, and faces diagonally downward. The upper flow path 60a and the lower flow path 60b are connected via a bent portion 74 that is slightly curved in an arc shape. The lower end of the lower flow path 60b is a suction port of the suction passage 60, and an oil strainer 61 is attached to the suction port. The oil strainer 61 is disposed at the bottom of the clutch chamber 28 in a state where the pump unit 20 is attached to the crankcase 12.

  The bent portion 74 is formed such that the top portion 74a is positioned above the maximum liquid level height L in the oil reservoir 29, that is, the maximum oil level height L of the oil in the working oil reservoir chamber 33. ing. Therefore, in the suction passage 60, a suction port (oil strainer 61) is provided on one end side of the bent portion 74, and the suction portion of the scavenging pump 32 is connected to the other end side of the bent portion 74.

  The scavenging pump 32 is driven by the operating oil pump 30 and the shaft portion 20a common to the lubricating oil pump 31, as described above. The end contacts the oil in the working oil reservoir 33. The common shaft portion 20a of the pump unit 20 is so high as to be immersed in the oil in the working oil storage chamber 33, that is, the regulated liquid level of the oil in the working oil storage chamber 33 (regulated by the communication hole 37). The liquid level is lower than the liquid level, and higher than the suction port (oil strainer 61) of the suction passage 60.

  The discharge passage 62 connected to the discharge portion of the scavenging pump 32 extends toward the lower front side of the scavenging pump 32 in the other end block 70B. The half body 12L is opened in a different direction on the side facing the rear partition wall 26. In the drawing, the opening is indicated by reference numeral 62a (for example, see FIG. 10). When the other end block 70B is fastened and fixed to the rear partition wall 26, the opening 62a communicates with the lubricating oil storage chamber 34 in the crankcase 12 through a communication hole (not shown) of the rear partition wall 26. Therefore, the oil sucked up from the clutch chamber 28 by the scavenging pump 32 flows into the lubricating oil storage chamber 34 through the communication hole of the rear partition wall 26.

  As shown in FIG. 11, a gauge insertion cylinder 77 into which an oil level gauge 76 is inserted is attached to the surface of the end block 70B facing the clutch chamber 28. The gauge insertion cylinder 77 extends substantially horizontally along the peripheral wall of the rear crank cover and then extends substantially horizontally, and its extension end is bent and connected to the connection hole 78 of the end block 70B. The connection hole 78 is formed through the end block 70B in the thickness direction at a position below the opening 62a of the discharge passage 62 on the end block 70B. The connection hole 78 communicates with the lubricating oil storage chamber 34 in the crankcase 12 through a communication hole (not shown) of the rear partition wall 26 when the other end block 70B is fastened and fixed to the rear partition wall 26. Accordingly, the oil in the lubricating oil storage chamber 34 flows into the gauge insertion cylinder 77 at the same liquid level through the connection hole 78, and the oil level gauge 76 can be visually confirmed by the oil level gauge 76. It becomes possible.

  Further, as shown in FIG. 15, the hydraulic pressure adjusting device 40 for adjusting the pressure of the oil supplied to the hydraulic clutches 50A and 50B is provided outside the rear crank cover 48, specifically, the end portions of the hydraulic clutches 50A and 50B. Is attached to a clutch cover 47 that covers the outer side. A part of the operating oil passage 39 connecting the hydraulic pressure adjusting device 40 and the hydraulic clutches 50A and 50B is formed in the clutch cover 47 portion.

FIG. 16 is a cross-sectional view showing a specific structure of a hydraulic pressure adjusting device 40 that is provided in the operating oil passage 39 and adjusts the pressure of oil supplied to the hydraulic clutches 50A and 50B. Two hydraulic pressure adjusting devices 40 are provided corresponding to the respective hydraulic clutches 50A and 50B, but since both have substantially the same structure, only one will be described below.
The hydraulic pressure adjusting device 40 includes an electromagnetic coil 80 whose energization current is controlled by a controller (not shown), a cylindrical wall 82 that is coaxially and integrally attached to a housing 81 of the electromagnetic coil 80, and an axial direction in the inner space of the electromagnetic coil 80. The movable core 83 movably disposed, the spool valve 84 slidably accommodated inside the cylindrical wall 82, the connecting rod 85 connecting the movable core 83 and the spool valve 84, and the spool valve 84 are initially installed. And a return spring 86 biasing toward the position. The cylindrical wall 82 has an oil introduction port 41 connected to the upstream side of the working oil passage 39 (the working oil pump 30 side) and the downstream side of the working oil passage 39 (the hydraulic clutches 50A, 50 side). A control port 42 to be connected and a drain port 43 for returning surplus oil to the working oil storage chamber 33 are provided. On the outer periphery of the spool valve 84, an annular groove 87 for selectively communicating the oil introduction port 41 and the drain port 43 with the control port 42 is provided.

The hydraulic pressure adjusting device 40 basically operates by a balance between the thrust force generated by the electromagnetic coil 80 acting on the spool valve 84 and the reaction force of the return spring 86. When the electromagnetic coil 80 is in the off state, the control port 42 is connected to the drain port 43. To conduct. When the electromagnetic coil 80 is excited, the spool valve 84 is displaced along the axial direction, and the oil introduction port 41 is appropriately conducted to the control port 42. The spool valve 84 is appropriately advanced and retracted in accordance with the energization control of the electromagnetic coil 80 and the pressure fluctuation on the hydraulic clutch 50A, 50B side, thereby controlling the hydraulic pressure supplied to the hydraulic clutch 50A, 50B. Note that reference numeral 88 in FIG. 16 is a pressure adjusting port that controls the pressure of the control port 42 on the spool valve 84 in the return direction and suppresses the sensitive fluctuation of the spool valve 84.
The drain port 43 is returned to the working oil storage chamber 33 through a return passage (not shown) in the clutch cover 47 and the rear crank cover 48 and the return port 89 of the end block 70B shown in FIGS.

Next, the flow of oil in the power unit case UC of the power unit PU of this embodiment will be described with reference to FIG.
During operation of the engine 11, the common shaft portion 20 a of the pump unit 20 is rotated by the rotation of the crankshaft 15, and accordingly, the three oil pumps 30, 31, 32 in the pump unit 20 are rotationally driven.

  Thus, in the operating oil pump 30, the oil sucked from the operating oil storage chamber 33 through the oil strainer 38 is discharged to the operating oil passage 39. In the operating oil passage 39, the oil pressure supplied to the hydraulic clutches 50 </ b> A and 50 </ b> B is appropriately adjusted by the hydraulic pressure adjusting device 40, and excess oil discharged from the drain port 43 is passed through the return passage 44 to the operating oil storage chamber. Return to 33. While the oil is supplied to the operating oil passage 39 in this way, a decrease in the oil pressure in the operating oil passage 39 is monitored by the hydraulic sensor 46.

  On the other hand, in the lubricating oil pump 31, the oil sucked from the lubricating oil storage chamber 34 through the oil strainer 55 is discharged to the lubricating oil passage 56. The oil discharged from the lubricating oil pump 31 is purified by passing through the lubricating oil filter 59, and then supplied to the lubricating portion such as the engine or transmission through the lubricating oil passage 56. The oil that has been lubricated by the lubrication part is returned to the lubricating oil storage chamber 34 again. The oil immediately after passing through the lubricating oil filter 59 in the lubricating oil passage 56 branches off in the transition passage 58, and a part thereof flows into the working oil storage chamber 33 through the transition passage 58. While the oil is supplied to the lubricating oil passage 56 in this way, a drop in the oil pressure in the lubricating oil passage 56 is monitored by the low pressure hydraulic switch 57.

  In the scavenging pump 32, the oil sucked from the clutch chamber 28 through the oil strainer 61 is caused to flow into the lubricating oil storage chamber through the discharge passage 62.

In this way, while the three oil pumps 30, 31, 32 in the pump unit 20 are rotationally driven, a part of the oil discharged to the lubricating oil passage 56 and the operating oil passage 39 is transferred to the transition passage 58 and the hydraulic pressure adjusting device. The oil flows into the working oil storage chamber 33 through the 40 drain ports 43. Thus, when the oil continuously flows into the working oil storage chamber 33, the oil in the working oil storage chamber 33 exceeds the height of the communication hole 37 of the upper wall 36 and passes through the communication hole 37 to lubricate the lubricating oil. It will flow into the storage chamber 34. The oil that has lubricated each part through the lubrication oil passage 56 is also returned to the lubrication oil storage chamber 34. However, the lubrication oil storage chamber 34 has a larger bottom area than the operation oil storage chamber 33 and operates. Since the amount of oil flowing into the oil storage chamber 33 is large, the oil level in the working oil storage chamber 33 is easily maintained higher than the oil level in the lubricating oil storage chamber 34.
Therefore, when the amount of oil in the power unit case UC decreases, the timing at which the oil in the lubricating oil passage 56 starts to decrease in pressure is earlier than the oil in the operating oil passage 39, and the lubricating oil passage 56. The internal low pressure hydraulic switch 57 outputs a warning signal before the hydraulic sensor 46 in the operating oil passage 39.

  Further, in the scavenging oil system, when the scavenging pump 32 is driven as the engine 11 is driven, the oil in the clutch chamber 28 is received by the oil strainer 61 by receiving the suction force from the suction portion of the scavenging pump 32. And is sucked into the lower flow path 60b of the suction passage 60. The oil sucked into the lower flow path 60b rises upward in the lower flow path 60b, passes over the top 74a of the bent portion 74, flows into the upper flow path 60a, and sucks into the suction part of the scavenging pump 32 via the upper flow path 60a. Can be put. The suction passage 60 has a bent portion 74 that is bent upward and convex in the middle of the passage. However, during the driving of the scavenging pump 32, the oil easily gets over the bent portion 74 by the suction force of the pump, and there is no problem in the clutch chamber. The oil in 28 can be sucked up.

On the other hand, when the driving of the scavenging pump 32 is stopped along with the stop of the engine 11, the oil in the lower flow path 60 b of the suction passage 60 is subjected to its own weight that attempts to drop downward. The oil in the working oil storage chamber 33 tends to enter through the peripheral region of the shaft portion 20a of the pump unit 20. The pressure of the oil that is about to enter the scavenging pump 32 via the peripheral region of the shaft portion 20a is due to the difference in height between the oil level L in the working oil storage chamber 33 and the shaft portion 20a. Is.
Here, in the case of the suction passage 60 of this embodiment, the top 74a of the bent portion 74 is formed so as to be positioned above the oil level L of the oil in the working oil storage chamber 33. The oil that has entered the scavenging pump 32 via the peripheral region of the shaft portion 20 cannot get over the top portion 74 a of the bent portion 74. Therefore, oil does not flow backward from the inside of the scavenging pump 32 to the lower flow path 60b side of the suction passage 60 under normal conditions.

As described above, in the power unit PU according to this embodiment, the bent top portion 74 a is at the oil level in the working oil storage chamber 33 in the suction passage 60 connected to the suction portion of the scavenging pump 32. Since the bent portion 74 positioned above L is provided, even when the scavenging pump 32 is stopped for a long time, the oil in the working oil storage chamber 33 is transferred to the periphery of the shaft portion 20a of the pump unit 20. Backflow into the clutch chamber 28 via the region and the suction passage 60 can be suppressed.
In this embodiment, the oil in the clutch chamber 28 of the power unit PU is caused to flow into the lubricating oil storage chamber 34 by the scavenging pump 32, but the low liquid level that sucks up the oil by the scavenging pump 32. The chamber is not necessarily the clutch chamber 28, and the scavenging pump 32 can be applied to a space other than the clutch chamber 28 as long as it is a space where it is desired to lower the oil level.

  However, the power unit PU according to this embodiment can suck the oil in the clutch chamber 28 into the lubricating oil storage chamber 34 by the scavenging pump 32 and can keep the oil level in the clutch chamber 28 low. Further, it is possible to suppress an increase in rotational resistance due to oil during rotation and operation of the hydraulic clutches 50A and 50B.

  In particular, in the power unit PU of this embodiment, the oil level in the clutch chamber 28 can be kept low as described above even when the driving of the scavenging pump 32 is stopped. The oil soaking of 50A and 50B can be suppressed as much as possible, and the startability of the engine 11 can be improved.

  Further, in the power unit PU according to this embodiment, the scavenging pump 32 shares the shaft portion 20a with the operation oil pump 30 and the lubrication oil pump 31, so that the integral oil unit 20 has an inside of the operation oil storage chamber 33. Therefore, the scavenging pump 32 can be compactly disposed in the working oil storage chamber 33 together with the working oil pump 30 and the lubricating oil pump 31. Therefore, the power unit PU can be easily downsized.

Further, in the power unit PU of this embodiment, the oil sucked up from the clutch chamber 28 by the scavenging pump 32 does not flow directly into the operating oil storage chamber 33, but is separated from the operating oil storage chamber 33. Since the passage is configured to flow into the chamber 34, it is possible to prevent the oil in the working oil storage chamber 33 from being agitated by the oil discharged from the scavenging pump 32.
That is, since the oil discharged from the scavenging pump 32 is taken in from the portion having a low liquid level in the clutch chamber 28, there is a possibility that the oil in the discharge portion may be vigorously stirred due to air entrainment or the like. On the other hand, in the power unit PU according to this embodiment, oil discharge from the scavenging pump 32 does not directly flow into the working oil storage chamber 33, so that the oil is stirred in the working oil storage chamber 33. Can be prevented in advance.

In the power unit PU of this embodiment, an operating oil storage chamber 33 is provided in the left case half 12L of the clan case 12 by being separated by a rear partition wall 26 (main partition wall) and a peripheral wall 27 (sub partition wall). In addition, since the rear partition wall 26 is provided with an opening 66 communicating with the inside of the working oil storage chamber 33 and allowing the main part of the pump unit 20 to be inserted, the crank having the working oil storage chamber 33 integrally therewith. The left case half 12L of the case 12 can be easily formed by casting.
That is, when manufacturing the left case half body 12L, for example, by casting the left case half body 12L using the surface along the rear partition wall 26 as a mold splitting surface, the oil storage chamber 33 for operation is separated during mold splitting. The convex shape forming the concave space can be easily pulled out through the portion corresponding to the opening 66 of the rear partition wall 26.
Therefore, by adopting this configuration, it is possible to reduce the manufacturing cost of the clack case 12.

  In the case of the power unit PU of this embodiment, the end block 70B of the pump unit 20 is opened with the main part of the pump unit 20 inserted into the working oil storage chamber 33 through the opening of the left case half 12L. Since the main part of the pump unit 20 can be installed in the working oil storage chamber 33 by being coupled to the peripheral portion of the 66, there is an advantage that the installation work of the pump unit 20 becomes easy.

In addition, this invention is not limited to said embodiment, A various design change is possible in the range which does not deviate from the summary. For example, the engine 11 built in the power unit PU is not limited to the horizontally opposed type, and may be a parallel or V-type multi-cylinder engine or a single-cylinder engine. Further, the engine 11 is not limited to a vertically placed engine having the crankshaft 15 along the vehicle front-rear direction, and may be a horizontally placed engine having the crankshaft along the vehicle left-right direction.
Vehicles to which the present invention is applied are not limited to motorcycles (including motorbikes and scooter type vehicles), but also three-wheel vehicles (including front-wheel and rear-wheel vehicles as well as front-wheel and rear-wheel vehicles) or four-wheel vehicles. A small wheeled vehicle is also included.

11 ... Engine 12L ... Left case half (case parts)
DESCRIPTION OF SYMBOLS 15 ... Crankshaft 20 ... Pump unit 20a ... Shaft part 26 ... Rear partition (main partition)
27 ... Peripheral wall (sub partition wall)
28 ... Clutch chamber (low liquid level chamber)
DESCRIPTION OF SYMBOLS 29 ... Oil reservoir 31 ... Oil pump for lubrication 32 ... Scavenging pump 33 ... Oil reservoir for operation 34 ... Oil reservoir for lubrication (another oil reservoir)
50A, 50B ... Hydraulic clutch 60 ... Suction passage 61 ... Oil strainer (suction port)
66 ... Opening 74 ... Bending part 70B ... End block (end wall)

Claims (4)

An oil reservoir (29) provided in the power unit case (UC);
A low liquid level chamber (28) provided in the power unit case (UC) and separated from the oil reservoir (29);
A scavenging pump (32) disposed in the oil reservoir (29) and sucking up oil in the low liquid level chamber (28) to another part in the power unit case (UC);
A suction passage (60) in which a suction port (61) arranged on one end side opens into the low liquid level chamber (28) and the other end is connected to a suction portion of the scavenging pump (32). ,
The shaft portion (20a) of the scavenging pump (32) is higher than the suction port (61) of the suction passage (60) and is higher than the liquid level of the oil contacting the oil reservoir (29). A power unit arranged in a low position,
The suction passage (60) has a bent portion (74) positioned above the liquid level of the oil in the oil reservoir (29), and the suction passage is provided at one end of the bent portion (74). A power unit provided with a mouth (61) and connected to the suction part of the scavenging pump (32) on the other end side of the bent part (74). In the power unit case (UC), there are disposed a crankshaft (15) of the engine (11) and hydraulic clutches (50A, 50B) for connecting and disconnecting power below the crankshaft (15). A clutch chamber (28) is provided by separating the hydraulic clutch (50A, 50B) from the oil reservoir (29),
The power unit according to claim 1, wherein the clutch chamber (28) is the low liquid surface chamber. The oil storage section (29) includes an operation oil storage chamber (33) for storing oil that operates the hydraulic clutch (50A, 50B), and an oil storage chamber (33) separate from the operation oil storage chamber (33). 34)
The scavenging pump (32) and the operating oil pump (30) for pumping oil for operating the hydraulic clutch (50A, 50B) share a drive system in the operating oil storage chamber (33). Provided coaxially,
The power unit according to claim 2, wherein the scavenging pump (32) causes the oil sucked up from the clutch chamber (28) to flow into the other oil storage chamber (34). A lubricating oil pump (31) for lubricating movable parts in the power unit case (UC);
The scavenging pump (32), the operating oil pump (30), and the lubricating oil pump (31) are configured as an integral pump unit (20) sharing a drive system, and the pump unit An end wall (70B) is provided on one end side in the axial direction of (20),
The case part (12L) constituting the power unit case (UC) is provided with a main partition wall (26) that divides the power unit case (UC) into the clutch chamber (28) and the oil reservoir (29). In addition, a sub-partition wall (27) is provided that divides the inside of the oil reservoir (29) into the oil reservoir for operation (33) and the other oil reservoir (34),
The main partition wall (26) is provided with an opening (66) communicating with the working oil storage chamber (33).
The main part of the pump unit (20) is inserted into the working oil storage chamber (33) from the other end side of the pump unit (20), and the end wall (70B) of the pump unit (20). 4. The power unit according to claim 3, wherein the power unit is coupled to a peripheral edge of the opening.

Images