JP2021162139A - Power transmission device - Google Patents

Abstract

To provide a power transmission device which can supply a lubrication oil to a spline fitting part installed in a connection chamber between a first case and a second case and enables improvement of lubrication performance of the spline fitting part.SOLUTION: A transmission 1 includes an outer fitting part 5C and an inner fitting part 6D which are respectively provided at a left wall 5W and a right wall 6W so as to enclose an outer peripheral spline 11s of a rotary shaft 11 and an inner peripheral spline 15s of a rotary shaft 15 and connect the left wall 5W with the right wall 6W. A space enclosed by the left wall 5W, the right wall 6W, the outer fitting part 5C, and the inner fitting part 6D forms a connection chamber 18 in which a spline fitting part 17 is installed. The left wall 5W of a left case 5 has an inflow port 5a which allows a lubrication oil to flow from the left case 5 into the connection chamber 18. A spline hole 15b has an opening end 15c facing the left wall 5W and the opening end 15c is located below the inflow port 5a.SELECTED DRAWING: Figure 6

Description

The present invention relates to a power transmission device.

A power transmission device described in Patent Document 1 is known as a power transmission device for connecting cases while connecting shafts provided in separate cases.

This power transmission device has an output shaft housed in the housing of the transmission, and the spline shaft portion of the output shaft projects from the partition wall of the housing toward the transfer side.

The input shaft is housed in the transfer housing, and the spline bearing of the input shaft projects from the partition wall of the transfer housing toward the transmission side.

The shaft portion of the output shaft and the shaft portion of the input shaft are installed in a space surrounded by the housing of the transmission and the housing of the transfer. The shaft portion of the output shaft and the shaft portion of the input shaft are connected to a connecting shaft having a spline formed on the inner peripheral portion, and power is transmitted to the output shaft and the input shaft via the connecting shaft.

Japanese Unexamined Patent Publication No. 2005-201352

However, in the power transmission device described in Patent Document 1, there is no circulation of lubricating oil between the transfer and the transmission. That is, it is surrounded by the housing of the transmission and the housing of the transfer, and the lubricating oil is not introduced into the space where the shaft portion of the output shaft and the shaft portion of the input shaft are installed.

Therefore, the shaft portion of the output shaft, the shaft portion of the input shaft, and the connecting shaft must be lubricated with grease, and the lubrication performance may deteriorate when the power transmission device is used for a long period of time. Therefore, the shaft portion of the output shaft, the shaft portion of the input shaft, and the connecting shaft may be worn, resulting in deterioration of durability.

The present invention has been made by paying attention to the above circumstances, and can supply lubricating oil to the spline fitting portion installed in the connection chamber between the first case and the second case, and the spline fitting portion. It is an object of the present invention to provide a power transmission device capable of improving the lubrication performance of the above.

In the present invention, an outer peripheral spline is formed at one end of a first case having a first wall portion and a second case having a second wall portion facing the first wall portion, and the outer peripheral spline is formed. A first rotating shaft supported by the first wall portion via a bearing so that the spline projects from the first wall portion toward the second wall portion, and one end of the spline fits into the outer peripheral spline. The second wall portion has a spline hole in which an inner peripheral spline to be combined is formed, and the inner peripheral spline projects from the second wall portion toward the first wall portion via a bearing. The first wall portion and the second wall portion are provided so as to surround the second rotation shaft supported by the outer peripheral spline and the inner peripheral spline, and the first wall portion and the first wall portion are provided. A power transmission device having a connecting portion for connecting the two wall portions, wherein the space surrounded by the first wall portion, the second wall portion, and the connecting portion is the inner peripheral spline and the connecting portion. A connection chamber in which a spline fitting portion into which an inner peripheral spline is fitted is installed, and the first wall portion provides an inflow port for lubricating oil to flow into the connection chamber from the inside of the first case. The spline hole has an opening end facing the first wall portion, and the opening end is located below the inflow port.

As described above, according to the present invention, the lubricating oil can be supplied to the spline fitting portion installed in the connection chamber between the first case and the second case, and the lubrication performance of the spline fitting portion can be improved.

FIG. 1 is a view of the power transmission device according to the embodiment of the present invention viewed from diagonally left rearward, and shows a state in which the reduction gear case and the reduction gear cover are removed from the left case. FIG. 2 is a view of the left case viewed diagonally to the right from the front by cutting the upper part of the left case of the power transmission device according to the embodiment of the present invention. FIG. 3 is a right side view of the speed reducer case of the power transmission device according to the embodiment of the present invention. FIG. 4 is a left side view of the front side portion of the power transmission device according to the embodiment of the present invention, and shows a state in which the speed reducer cover is removed. FIG. 5 is a left side view of the front side portion of the power transmission device according to the embodiment of the present invention, showing a state in which the reduction gear cover and the reduction gear case are removed. FIG. 6 is a cross-sectional view taken along the line in the VI-VI direction of FIG. FIG. 7 is a cross-sectional view taken along the line VII-VII of FIG.

The power transmission device according to the embodiment of the present invention has a first case having a first wall portion, a second case having a second wall portion facing the first wall portion, and one end portion thereof. An outer peripheral spline is formed on the first wall portion, and the outer peripheral spline is supported on the first wall portion via a bearing so that the outer peripheral spline projects from the first wall portion toward the second wall portion. The second wall portion has a spline hole in which an inner peripheral spline fitted to the outer peripheral spline is formed, and the inner peripheral spline projects from the second wall portion toward the first wall portion via a bearing. The first wall portion and the second wall portion are provided so as to surround the second rotation shaft supported by the outer peripheral spline and the inner peripheral spline, and the first wall portion and the second wall portion are formed. A power transmission device having a connecting portion to be connected, and a space surrounded by a first wall portion, a second wall portion, and a connecting portion is a spline fitting in which an inner peripheral spline and an inner peripheral spline are fitted. The first wall portion constitutes a connection chamber in which the portion is installed, the first wall portion has an inflow port for allowing lubricating oil to flow into the connection chamber from the inside of the first case, and the spline hole faces the first wall portion. It has an open end, which is located below the inlet.

As a result, the power transmission device according to the embodiment of the present invention can supply lubricating oil to the spline fitting portion installed in the connection chamber between the first case and the second case, and lubricate the spline fitting portion. Performance can be improved.

Hereinafter, the power transmission device according to an embodiment of the present invention will be described with reference to the drawings.
1 to 7 are views showing a power transmission device according to an embodiment of the present invention. In FIGS. 1 to 7, the up / down / front / rear / left / right directions are based on the power transmission device installed in the vehicle, the front / rear direction of the vehicle is the front / rear direction, the left / right direction of the vehicle (width direction of the vehicle) is the left / right direction, and the vehicle. The vertical direction (the height direction of the vehicle) is the vertical direction.

First, the configuration will be described.
In FIG. 1, a transmission 1 is installed in an engine room (hereinafter, simply referred to as a vehicle) of a hybrid vehicle (hereinafter, simply referred to as a vehicle), and an engine 2 as an internal combustion engine is connected to the transmission 1. The transmission 1 of the present embodiment constitutes the power transmission device of the present invention.

The transmission 1 includes a transmission case 3, and the transmission case 3 includes a right case 4, a left case 5, a reduction gear case 6, a reduction gear cover 7, and a parking cover 8 in this order from the side of the engine 2. Have. Each case and cover are connected by a plane perpendicular to the left-right direction. That is, the mating surfaces of the cases and covers are formed as surfaces perpendicular to the left-right direction.

The engine 2 is connected to the light case 4. The engine 2 has a crank shaft (not shown), and the crank shaft is installed so as to extend in the width direction of the vehicle (left-right direction, hereinafter, simply referred to as the vehicle width direction). The engine 2 of this embodiment is composed of a transverse engine, and the vehicle of this embodiment is a front engine / front drive (FF) vehicle.

The light case 4 has a peripheral wall whose right end is connected to the engine 2 and a partition wall 4W erected on the left end of the peripheral wall, and has a shape in which the right side is open.

The left case 5 is connected to the left end of the peripheral wall opposite to the engine 2 with respect to the right case 4. That is, the left case 5 is connected to the left side of the right case 4. A flange portion 4A is formed on the outer peripheral edge of the partition wall 4W of the light case 4.

The left case 5 is a case having a peripheral wall whose right end is connected to the right case 4 and a left wall 5W erected on the left end of the peripheral wall, and the right side is open.

A flange portion 5A is formed at the right end of the peripheral wall of the left case 5. The flange portion 4A is fastened to the flange portion 5A by a bolt (not shown), and the right case 4 and the left case 5 are connected via the flange portions 4A and 5A.

A clutch (not shown) is housed in the space inside the light case 4 located on the right side of the partition wall 4W. A transmission chamber 9 is formed in a space surrounded by the partition wall 4W of the right case 4 and the left wall 5W of the left case 5, that is, inside the left case 5 (see FIGS. 2 and 6). A plurality of rotating shafts for transmitting power from the engine 2 to a differential device (not shown) are housed in the engine 2.

FIG. 2 shows one rotation shaft 11 of the plurality of rotation shafts. The rotary shaft 11 is installed on a power transmission path between the engine 2 and the differential device, and has a plurality of gears 11A and 11B for shifting and a synchronization device 12.

The gears 11A and 11B for shifting are rotatable relative to the rotating shaft 11, and mesh with gears for shifting (not shown) of other rotating shafts (not shown).

The synchronization device 12 is installed between the gears 11A and 11B for shifting in the axial direction of the rotating shaft 11.

As shown in FIG. 6, the synchronization device 12 includes a hub 12A, a sleeve 12B, and synchronizer rings 12C, 12D.

In the synchronous device 12, when the shift stage is shifted to the first shift stage (for example, the first gear) or the second gear (for example, the second gear) by the shift operation, the sleeve 12B is not shown from the neutral position. It is moved by the shift fork to the gear 11A side for shifting or the gear 11B side for shifting, and any one of the gear 11A for shifting and the gear 11B for shifting is connected to the rotating shaft 11 via the synchronization device 12. do.

As a result, power is transmitted to the gear 11A for shifting or another rotating shaft that meshes with the gear 11B for shifting. Therefore, the power of the engine 2 is transmitted to the differential device via the rotating shaft 11.

The differential device distributes the power of the engine 2 to the left and right drive shafts (not shown) and transmits the power to the drive wheels (not shown).

As shown in FIGS. 3 and 4, the speed reducer case 6 has a right side wall 6W, a peripheral wall 6A formed on the outer peripheral edge of the right side wall 6W, and a disk-shaped motor mounting portion provided above the right side wall 6W. Has 6B and. As shown in FIG. 1, the speed reducer cover 7 has a left side wall 7W and a peripheral wall 7A formed on the outer peripheral edge of the left side wall 7W.

As shown in FIG. 6, the left side wall 7W of the speed reducer cover 7 is opposite to the left side wall 5W of the left case 5 with respect to the right side wall 6W of the speed reducer case 6 in the axial direction of the rotation shaft 11 and the rotation shaft 15 described later. It is located on the side (left side). That is, these walls are arranged in the order of the left side wall 7W of the speed reducer cover 7, the right side wall 6W of the speed reducer case 6, and the left side wall 5W of the left case 5 from the left side.

As shown in FIG. 1, the peripheral wall 7A of the speed reducer cover 7 is fastened to the peripheral wall 6A of the speed reducer case 6 by a plurality of bolts 10. Some of the bolts 10 are fastened to the left side wall 5W from the reduction gear cover 7 through the reduction gear case 6, and the reduction gear case 6 and the reduction gear cover 7 are integrally attached to the left case 5. There is.

As shown in FIG. 6, in a state where the speed reducer case 6 is attached to the left case 5, the right side wall 6W of the speed reducer case 6 faces the left side wall 5W of the left case 5. That is, the left side wall 5W of the left case 5 and the right side wall 6W of the speed reducer case 6 face each other in the axial direction of the rotation shafts 11 and 15.

The left case 5 of the present embodiment constitutes the first case of the present invention, and the speed reducer case 6 and the speed reducer cover 7 constitute the second case of the present invention. The left side wall 5W of the left case 5 constitutes the first wall portion of the present invention, and the right side wall 6W of the speed reducer case 6 constitutes the second wall portion of the present invention. The rotary shaft 11 constitutes the first rotary shaft of the present invention, and the rotary shaft 15 constitutes the second rotary shaft of the present invention.

A motor for traveling (not shown) is attached to the motor mounting portion 6B of the speed reducer case 6, and the motor is mounted on the left case 5 integrally with the speed reducer case 6 and the speed reducer cover 7.

As shown in FIG. 6, a cylindrical bearing support portion 5B is formed on the left side wall 5W of the left case 5, and the bearing support portion 5B is inside the left case 5 (deceleration) from the left side wall 5W of the left case 5. It protrudes to the opposite side of the machine case 6.

The left end portion 11f of the rotating shaft 11 is rotatably supported by the bearing supporting portion 5B via the ball bearing 14A. The left end portion 11f of the rotating shaft 11 of the present embodiment constitutes the end portion of the first rotating shaft of the present invention, and the ball bearing 14A constitutes the bearing of the present invention.

A bearing support portion (not shown) is formed on the partition wall 4W of the right case 4, and the bearing support portion projects from the partition wall 4W of the right case 4 to the left side wall 5W side of the left case 5. The right end portion 11r of the rotating shaft 11 is rotatably supported by a bearing supporting portion (not shown) of the partition wall 4W via a bearing.

As shown in FIGS. 1, 5, and 6, an opening 5h is formed in the left wall 5W of the left case 5, and the opening 5h opens inward in the radial direction of the bearing support portion 5B. There is. As shown in FIG. 6, an outer peripheral spline 11s is formed at the left end portion 11f of the rotating shaft 11.

The outer peripheral spline 11s of the rotating shaft 11 projects from the left case 5 (transmission chamber 9) to the right side wall 6W side of the speed reducer case 6 through the opening 5h. That is, the outer peripheral spline 11s of the rotating shaft 11 is located outside the transmission chamber 9 of the left case 5.

In this way, the rotating shaft 11 extends to the left side wall 5W of the left case 5 via the ball bearing 14A so that the outer peripheral spline 11s projects from the left side wall 5W of the left case 5 to the right side wall 6W side of the speed reducer case 6. It is supported.

A reduction gear chamber 13 is formed in the space surrounded by the reduction gear case 6 and the reduction gear cover 7, that is, inside the reduction gear case 6 and the reduction gear cover 7, and the reduction shaft 15 and the chain are formed in the reduction gear chamber 13. 16 is housed.

The rotary shaft 15 is erected on the speed reducer case 6 and the speed reducer cover 7, the right end portion 15r of the rotary shaft 15 is supported by the right end wall 6W of the speed reducer case 6, and the left end portion 15f of the rotary shaft 15 is the speed reducer cover 7. It is supported by the left wall 7W of. The shaft length of the rotating shaft 15 is formed to be shorter than the shaft length of the rotating shaft 11. A sprocket 15A is provided on the outer peripheral portion of the rotating shaft 15, and the sprocket 15A rotates integrally with the rotating shaft 15.

As shown in FIGS. 4 and 6, a bearing support portion 6C is formed on the right side wall 6W of the speed reducer case 6, and the right end portion 15r of the rotating shaft 15 is connected to the bearing support portion 6C via the ball bearing 14B. It is rotatably supported. The right end portion 15r of the rotating shaft 15 of the present embodiment constitutes one end portion of the second rotating shaft of the present invention, and the ball bearing 14B constitutes the bearing of the present invention.

As shown in FIG. 6, a bearing support portion 7B is formed on the left side wall 7W of the reduction gear cover 7, and the bearing support portion 7B is from the left side wall 7W of the reduction gear cover 7 to the right side wall 6W of the reduction gear case 6. It protrudes to the side.

The left end portion 15f of the rotating shaft 15 is rotatably supported by the bearing supporting portion 7B via the ball bearing 14C. The left side wall 7W of the speed reducer cover 7 of this embodiment constitutes a third wall portion of the present invention.

As the ball bearing 14A that supports the rotating shaft 11, bearings larger than the ball bearings 14B and 14C that support the rotating shaft 15 are used. The ball bearing 14A has an outer diameter larger than that of the ball bearings 14B and 14C, and the annular gap between the inner ring and the outer ring (the gap in which the rolling element and the cage are arranged) in the ball bearing 14A is that of the ball bearings 14B and 14C. It has a larger diameter than that.

The opening 5h of the left case 5 is a substantially circular opening, and the central axis of the opening 5h of the left wall 5W of the left case 5 is the rotation center axis of the ball bearings 14A, 14B, 14C and the rotation axes 11, 15 It is installed so that it is the same as the central axis of.

The inner diameter of the opening 5h of the left wall 5W of the left case 5, that is, the diameter of the opening 5h is formed to be smaller than the outer diameter of the ball bearing 14B. Specifically, the diameter of the opening 5h is formed so as to be substantially equal to or smaller than the outer ring shoulder diameter dimension of the ball bearing 14B. Further, the diameter of the opening 5h is formed so as to be substantially equal to or smaller than the inner ring shoulder diameter dimension of the ball bearing 14A.

As shown in FIGS. 3, 4, and 6, an opening 6h is formed in the right side wall 6W of the speed reducer case 6, and the opening 6h opens inward in the radial direction of the bearing support portion 6C. ing. Specifically, the diameter of the opening 6h is formed to be smaller than the outer diameter dimension of the outer ring of the ball bearing 14B. Further, the diameter of the opening 6h is formed so as to be substantially equal to or smaller than the outer ring shoulder diameter dimension of the ball bearing 14B.

A through hole 15B is formed in the rotating shaft 15, and the through hole 15B penetrates in the axial direction of the rotating shaft 15. A spline hole 15b is formed in the right end portion 15r of the through hole 15B, and an inner peripheral spline 15s is formed in the spline hole 15b along the spline hole 15b.

In the axial direction of the rotating shaft 15, the spline hole 15b is formed from the position of the left side surface of the ball bearing 14B over the opening end 15c of the spline hole 15b.

The through hole 15B of this embodiment is in the range from the opening end 15d on the left end portion 15f side of the rotating shaft 15 to the opening end 15c on the right end portion 15r side, and the inner peripheral spline 15s is formed in the through hole 15B. The portion is formed of the spline hole 15b.

The opening end 15c of the spline hole 15b faces the left side wall 5W of the left case 5, and the opening end 15d of the through hole 15B faces the left side wall 7W of the speed reducer cover 7. The opening end 15c, which is the end of the inner peripheral spline 15s of the rotating shaft 15, projects from the right side wall 6W of the speed reducer case 6 to the left side wall 5W side of the left case 5 through the opening 6h. At least a part of the inner peripheral spline 15s of the rotating shaft 15 is arranged in the opening 6h.

That is, the rotating shaft 15 is supported on the right side wall 6W of the speed reducer case 6 via the ball bearing 14B so that the inner peripheral spline 15s projects from the right side wall 6W of the speed reducer case 6 to the left side wall 5W side of the left case 5. Has been done.

The outer spline 11s of the rotating shaft 11 is inserted into the spline hole 15b of the rotating shaft 15, and the outer spline 11s of the rotating shaft 11 is fitted to the inner spline 15s of the rotating shaft 15.

As a result, the rotating shaft 15 rotates integrally with the rotating shaft 11. The outer peripheral spline 11s of the rotating shaft 11 and the inner peripheral spline 15s of the rotating shaft 15 fitted to the outer peripheral spline 11s constitute a spline fitting portion 17. The rotary shaft 11 has a spline hole 15b of the rotary shaft 15 so that the left end portion 11f of the rotary shaft 11 is located on the left side wall 7W side of the speed reducer cover 7 with respect to the left side surface of the ball bearing 14B in the axial direction of the rotary shaft 15. It is inserted in.

The chain 16 is wound around a sprocket 15A of a rotating shaft 15 and a motor sprocket (not shown) attached to a motor shaft (not shown) of the motor. The power of the motor is transmitted from the motor sprocket to the rotating shaft 15 via the chain 16 and the sprocket 15A.

The power of the motor transmitted to the rotating shaft 15 is transmitted from the rotating shaft 15 to the differential device via the rotating shaft 11, and then transmitted from the left and right drive shafts to the left and right drive wheels. As a result, the vehicle is driven by the motor alone or by both the motor and the engine 2.

On the other hand, the power transmitted from the drive wheels to the differential device via the left and right drive shafts when the vehicle is decelerated is transmitted from the rotary shaft 11 to the motor via the rotary shaft 15 and the chain 16. As a result, the motor generates regenerative power generation.

A cylindrical outer fitting portion 5C is formed on the left side wall 5W of the left case 5, and the outer fitting portion 5C projects from the left side wall 5W of the left case 5 to the right side wall 6W side of the speed reducer case 6. ..

A cylindrical inner fitting portion 6D is formed on the right side wall 6W of the speed reducer case 6. The inner fitting portion 6D projects from the right side wall 6W of the speed reducer case 6 to the left side wall 5W side of the left case 5, and is fitted to the inner peripheral surface of the outer fitting portion 5C.

The speed reducer case 6 of this embodiment is attached to the left case 5 by connecting the right side wall 6W to the left side wall 5W of the left case 5 via the outer fitting portion 5C and the inner fitting portion 6D. .. The outer fitting portion 5C and the inner fitting portion 6D of the present embodiment constitute the connecting portion of the present invention.

The outer fitting portion 5C and the inner fitting portion 6D surround the spline fitting portion 17, the outer fitting portion 5C, the inner fitting portion 6D, the left wall 5W of the left case 5, and the right side of the speed reducer case 6. The space surrounded by the wall 6W constitutes the connection chamber 18 in which the spline fitting portion 17 is installed.

A seal member (O-ring) 30 is provided between the inner fitting portion 6D and the outer fitting portion 5C to prevent the lubricating oil from leaking from between the inner fitting portion 6D and the outer fitting portion 5C. doing. That is, the connection chamber 18 is sealed with the outer space of the transmission case 3 by the seal member 30.

As shown in FIG. 2, a notch 5 g is formed in the upper portion of the bearing support portion 5B, and the notch 5 g communicates the inside of the bearing support portion 5B with the transmission chamber 9. Specifically, the notch 5g reaches from the outside of the bearing support portion 5B to the outer ring of the ball bearing 14A, and the upper surface of the ball bearing 14A is exposed in the transmission chamber 9 through the notch 5g. Further, in the axial direction of the rotating shaft 11, the notch 5 g reaches the right side wall 6W side of the speed reducer case 6 from the left side surface of the ball bearing 14A.

As shown in FIGS. 5 and 6, an inflow port 5a is formed in the left wall 5W of the left case 5, and the inflow port 5a is located above the openings 5h located above the rotation shafts 11 and 15. It is formed.

The inflow port 5a is an end portion on the left side of the notch 5g (on the right side wall 6W side of the speed reducer case 6) in the axial direction of the rotating shaft 11, and is an opening portion of the notch 5g to the connection chamber 18. As a result, the inflow port 5a communicates with the transmission chamber 9 and communicates with the connection chamber 18 via the notch 5g of the bearing support portion 5B. Therefore, the transmission chamber 9 and the connection chamber 18 communicate with each other through the inflow port 5a.

As shown in FIG. 2, an oil gutter 21 is installed in the left case 5. The oil gutter 21 has a right side oil gutter 22 and a left side oil gutter 23. The right oil gutter 22 has a first oil gutter portion 22A extending in the front-rear direction and a second oil gutter portion 22B bent left from the front end of the first oil gutter portion 22A and extending in the vehicle width direction.

The left oil gutter 23 has a first oil gutter 23A extending to the left from a position overlapping below the left end of the second oil gutter 22B.

The left oil gutter 23 has a second oil gutter portion 23B extending from the left end of the first oil gutter portion 23A to the lower front side. The tip of the second oil gutter portion 23B in the extending direction is arranged so as to face the inflow port 5a in the axial direction of the rotating shafts 11 and 15 and to overlap the notch 5g in the vertical direction.

The first oil gutter portion 22A is located in front of a final driven gear (not shown) of the differential device. Lubricating oil is stored (stored) in the bottom of the left case 5. The lubricating oil scraped up by the final driven gear is introduced into the first oil gutter portion 22A and flows from the first oil gutter portion 22A to the second oil gutter portion 22B.

The lubricating oil that has flowed into the second oil gutter portion 22B is introduced into the first oil gutter portion 23A of the left oil gutter 23, flows from the first oil gutter portion 23A to the second oil gutter portion 23B, and then flows into the second oil gutter portion 23B. It is guided from 23B to the inflow port 5a through the notch 5g.

The lubricating oil guided from the second oil gutter portion 23B to the inflow port 5a through the notch 5g flows into the connection chamber 18 from the inflow port 5a. That is, the lubricating oil scraped up by the final driven gear flows into the notch 5 g formed in the upper part of the bearing support portion 5B by the oil gutter 21 (right oil gutter 22 and left oil gutter 23), and the lubricating oil that has flowed into the notch 5 g , It flows into the connection chamber 18 from the inflow port 5a that opens at the upper part of the connection chamber 18.

As shown in FIG. 6, the opening end 15c of the spline hole 15b of the rotating shaft 15 is located below the inflow port 5a, and the lubricating oil flowing in (flowing down) from the inflow port 5a into the connection chamber 18 is a spline hole. It falls on the rotating shaft 11 at the open end 15c of 15b and its vicinity. Therefore, the lubricating oil is supplied to the inside of the spline hole 15b through the open end 15c.

As shown in FIG. 6, an oil channel 24 is provided at the opening end 15d on the left end portion 15f side of the rotating shaft 15 facing the left side wall 7W of the speed reducer cover 7.

The oil channel 24 has a disk portion 24A and a tubular portion 24B. The disk portion 24A faces the left side wall 7W of the speed reducer cover 7 via a certain gap, and is sandwiched between the bearing support portion 7B and the ball bearing 14C in the axial direction of the rotating shafts 11 and 15. , It is fixed to the speed reducer cover 7.

The tubular portion 24B is inserted into the through hole 15B and projects from the disc portion 24A toward the rotation shaft 11. The oil channel 24 of this embodiment constitutes the oil supply member of the present invention. Specifically, as shown in FIG. 6, the lubricating oil flowing down along the left side wall 7W of the speed reducer cover 7 is applied to the left side wall 7W and the disc portion 24A from the notch formed in the upper part of the bearing support portion 7B. It can be collected in the gap between them and introduced into the through hole 15B through the tubular portion 24B. The lubricating oil that has flowed into the through hole 15B is used for lubricating the spline fitting portion 17, and also flows into the ball bearing 14C and is used for lubrication thereof.

An outlet 6a is formed on the right side wall 6W of the speed reducer case 6 (see FIGS. 3 and 4), and the outlet 6a is formed below the bearing support portion 6C. The outlet 6a communicates the connection chamber 18 and the speed reducer chamber 13, and the lubricating oil inside the connection chamber 18 flows out to the speed reducer chamber 13 through the outlet 6a. The outlet 6a is formed by cutting out a part of the bearing support portion 6C, and the lubricating oil passes through the outer diameter side of the ball bearing 14B and flows out from the inside of the connection chamber 18 to the speed reducer chamber 13.

As shown in FIGS. 5 and 7, a return port 5b is formed on the left wall 5W of the left case 5, and the return port 5b communicates the connection chamber 18 with the transmission chamber 9 of the left case 5. There is. Specifically, the return port 5b is a lower portion of the left side wall 5W inside the outer fitting portion 5C, is formed in front of the opening 5h, and is formed with the connection chamber 18 and the transmission chamber 9 of the left case 5. Is communicating. Further, as shown in FIG. 2, the transmission chamber 9 side of the return port 5b is a notch formed in the bearing support portion 5B, and the lubricating oil flows outside the outer ring of the ball bearing 14A to flow in the transmission chamber. Return to 9.

As shown in FIGS. 3, 4, and 7, a return port 6b is formed on the right side wall 6W of the speed reducer case 6, and the return port 6b is connected to the return port 5b in the axial direction of the rotation shafts 11 and 15. Opposing (matching). The return port 6b communicates the connection chamber 18 and the speed reducer chamber 13. The return port 5b of the present embodiment constitutes the first case-side return port of the present invention, and the return port 6b constitutes the second case-side return port of the present invention. The left case 5 side of the return port 6b is a return chamber 26, which will be described later.

As shown in FIG. 7, the return port 6b faces the chain 16 in the axial direction of the rotating shafts 11 and 15, and extends diagonally forward and upward along the chain 16 as shown in FIG. ..

As shown in FIGS. 3 and 6, a partition wall 6E is formed on the right side wall 6W of the speed reducer case 6, and the partition wall 6E is from the wall surface 6w of the right side wall 6W (see FIG. 6) to the left side of the left case 5. It protrudes to the 5W side of the wall. The protruding height of the partition wall 6E is about the same as that of the inner fitting portion 6D, and protrudes to the vicinity of the left side wall 5W inside the outer fitting portion 5C. The tip of the partition wall 6E on the left case 5 side and the tip of the inner fitting portion 6D on the left case 5 side are machined to ensure dimensional accuracy.

As shown in FIG. 3, the partition wall 6E is located outside the opening 6h of the right side wall 6W in the radial direction and extends upward from the peripheral wall portion 6m extending in the circumferential direction of the rotation shaft 11 and the upper end of the peripheral wall portion 6m. Has a vertical wall portion 6n connected to the inner fitting portion 6D. The vertical wall portion 6n is located at the same height as the inflow port 5a formed on the left side wall 5W of the left case 5, and is located on the front side of the inflow port 5a. The lower portion of the peripheral wall portion 6m is connected to a protrusion 6d protruding upward from the inner fitting portion 6D. The protrusion 6d is provided at the same height as the outlet 6a and in front of the outlet 6a.

As shown in FIGS. 5 and 6, a partition wall 5D is formed on the left side wall 5W of the left case 5, and the partition wall 5D is moved from the wall surface 5w of the left side wall 5W to the right side wall 6W side of the speed reducer case 6. It is protruding. The protruding height of the partition wall 5D is not as high as that of the partition wall 6E, and the tip position of the partition wall 5D is almost the same as the tip position of the inner fitting portion 6D that enters the inside of the outer fitting portion 5C. The tip of the left side wall 5W inside the portion 5C, which protrudes slightly from the left side wall 5W and is on the reduction gear case 6 side, is machined to ensure dimensional accuracy. The partition wall 5D is formed so as to extend in the circumferential direction of the rotation shaft 11 and surround the opening 5h, and the inflow port 5a is formed so as to cut out the upper part of the partition wall 5D. On the front side of the inflow port 5a, the partition wall 5D extends upward from a portion extending in the circumferential direction of the rotation shaft 11.

The partition wall 5D faces the partition wall 6E of the right side wall 6W in the axial direction of the rotation shafts 11 and 15 via a minute gap. That is, the portion of the partition wall 5D formed so as to surround the opening 5h and the peripheral wall portion 6m are arranged in close proximity to each other, and the portion of the partition wall 5D extending upward on the front side of the inflow port 5a and the vertical wall. The portions 6n are arranged so as to face each other. The minute gap between the partition wall 5D and the partition wall 6E is a gap in which the lubricating oil does not easily flow out when the viscosity of the lubricating oil is taken into consideration. Then, as shown in FIGS. 3 and 7, the connection chamber 18 is divided into an inflow chamber 25, a return chamber 26, and a shaft chamber 27 by a partition wall 5D and a partition wall 6E.

The inflow chamber 25 communicates with the transmission chamber 9 of the left case 5 via the inflow port 5a, and communicates with the shaft chamber 27 via the communication portion 25c. The shaft chamber 27 has an outlet 6a at its lower portion, and communicates with the speed reducer chamber 13 via the outlet 6a. That is, the transmission chamber 9 and the reduction gear chamber 13 are communicated with each other via the connection chamber 18. Specifically, the transmission chamber 9 and the speed reducer chamber 13 communicate with each other via the inflow chamber 25, and the transmission chamber 9 and the speed reducer chamber 13 allow the lubricating oil to freely flow through the inflow chamber 25. ing.

The return chamber 26 communicates with the transmission chamber 9 via the return port 5b and also communicates with the speed reducer chamber 13 via the return port 6b. That is, the transmission chamber 9 and the reduction gear chamber 13 communicate with each other via the return chamber 26, and the transmission chamber 9 and the reduction gear chamber 13 allow the lubricating oil to freely flow through the return chamber 26. ..

As described above, in the connection chamber 18 of the present embodiment, lubricating oil is provided between the transmission chamber 9 and the speed reducer chamber 13 by the inflow chamber 25, the shaft chamber 27, and the return chamber 26 partitioned by the partition walls 5D and 6E. Two independent oil passages are formed through which the oil flows. As shown in FIG. 3, when viewed from the axial direction, the inflow chamber 25 is arranged in a range of approximately 90 degrees, which is the upper rear side of the opening 6h, and the shaft chamber 27 is approximately 90 degrees, which is the lower rear side of the opening 6h. The return chamber 26 is arranged on the front side of the opening 6h.

Since the internal space of the transmission chamber 9 is formed large at a position lower than the internal space of the speed reducer chamber 13, the vehicle is parked at the height positions of the return ports 5b and 6b (specifically, the position of the lower end). The amount of lubricating oil in the speed reducer chamber 13 when the vehicle is stopped can be set. Then, in this embodiment, the return ports 5b and 6b are installed at a height at which the lower portion of the sprocket 15A and the chain 16 can be immersed in the lubricating oil stored in the speed reducer chamber 13. The lower end of the return port 6b is set at a position lower than the lower end position of the inner diameter of the outer ring of the ball bearing 14B.

That is, the return port 5b and the return port 6b are communicated with each other through the return chamber 26, and the lubricating oil contained in the speed reducer chamber 13 passes from the return port 5b through the return chamber 26 and the return port 5b to the transmission chamber 9 Returned to.

Therefore, if the height positions of the return ports 5b and 6b are lower than the lower end of the sprocket 15A, the lubricating oil in the reduction gear chamber 13 will flow out to the transmission chamber 9 when the vehicle is parked and stopped. The oil level of the lubricating oil contained in 13 becomes excessively low, and the sprocket 15A and the chain 16 cannot be immersed in the lubricating oil, so that the sprocket 15A and the chain 16 may not be sufficiently lubricated with the lubricating oil at the initial stage of traveling.

On the other hand, when the height positions of the return ports 5b and 6b are set to high positions, the oil level of the lubricating oil contained in the speed reducer chamber 13 becomes excessively high, and the stirring resistance of the sprocket 15A and the chain 16 increases. At the same time, the temperature of the lubricating oil rises unnecessarily, which accelerates the deterioration.

Therefore, the return ports 5b and 6b of this embodiment are installed at a height at which the sprocket 15A and the chain 16 can be sufficiently lubricated and the stirring resistance of the sprocket 15A and the chain 16 does not increase. Specifically, it is formed at the same height as the lower portion of the sprocket 15A.

As shown in FIGS. 3 and 6, the connection chamber 18 has a shaft chamber 27. The shaft chamber 27 is a space that accommodates the spline fitting portion 17 inside the peripheral wall portion 6m of the partition wall 6E, and is arranged so as to surround the periphery of the outer peripheral portion of the spline fitting portion 17. The shaft chamber 27 communicates with the inflow chamber 25 via a communication portion 25c located behind the central axis of the spline fitting portion 17, and the lubricating oil flows into the shaft chamber 27. Further, the shaft chamber 27 is communicated with the speed reducer chamber 13 via an outflow port 6a located below the shaft chamber 27, and the lubricating oil flows out, and the lubricating oil flows in from the inflow port 5a located above the shaft chamber 27.

As shown in FIG. 3, the peripheral wall portion 6m is curved and extends from the lower portion of the inner fitting portion 6D to the vertical wall portion 6n, and then curved from the vertical wall portion 6n to the central portion in the vertical direction of the inner fitting portion 6D. It extends in the circumferential direction within a range of about 270 °. That is, the peripheral wall portion 6m is arranged so as to surround the outer peripheral portion of the spline fitting portion 17 except for the range from the communication portion 25c on the rear lower side of the spline fitting portion 17 to the outlet 6a.

Then, as shown in FIG. 3, a communication portion 25c is formed between the lower end of the peripheral wall portion 6m located at substantially the same height as the central portion 27a of the shaft chamber 27 on the rear side of the shaft chamber 27 and the inner fitting portion 6D. The inflow chamber 25 is communicated with the shaft chamber 27 via the communication portion 25c.

The outlet 6a is formed at the lowermost part of the shaft chamber 27, and the communication portion 25c communicates with the outlet 6a through the shaft chamber 27. That is, the lubricating oil flowing from the inflow chamber 25 into the shaft chamber 27 via the communication portion 25c flows down along the inner surface of the inner fitting portion 6D, reaches the outflow port 6a, and is supplied to the speed reducer chamber 13.

The upstream portion 25a of the inflow chamber 25 faces the inflow port 5a in the axial direction of the rotating shafts 11 and 15. The downstream portion 25b of the inflow chamber 25 communicates with the shaft chamber 27 via the communication portion 25c. Here, the upstream and downstream represent the upstream and downstream in the direction in which the lubricating oil flowing into the inflow chamber 25 from the inflow port 5a flows.

The shaft chamber 27 is located below the inflow chamber 25 and communicates with the downstream portion 25b of the inflow chamber 25 via the communication portion 25c.

That is, the inflow chamber 25 extends from the upstream portion 25a facing the inflow port 5a to the communication portion 25c located in the downstream portion 25b in the circumferential direction of the rotation shafts 11 and 15, and extends from the inflow port 5a to the inflow chamber 25. The inflowing lubricating oil flows from the upstream portion 25a of the inflow chamber 25 to the downstream portion 25b, and then flows into the shaft chamber 27 via the communication portion 25c.

The rotating shafts 11 and 15 rotate from the upstream portion 25a toward the downstream portion 25b with respect to the inflow chamber 25 when the vehicle moves forward (counterclockwise in FIG. 3), and the inflow chamber 25 rotates when the vehicle moves backward. It rotates from the downstream portion 25b toward the upstream portion 25a side (clockwise in FIG. 3).

As shown in FIG. 3, the central portion 27a of the shaft chamber 27 (the central portion of the partition wall 5D, the central portion of the peripheral wall portion 6 m of the partition wall 6E) is the central portion 6c of the inner fitting portion 6D (outer fitting portion 5C). The space is eccentric to the lower front side with respect to the central portion of the shaft chamber 27, and spaces are secured on the upper side and the front side of the shaft chamber 27. As a result, a relatively large space is secured and arranged within the limited fitting portion diameter. Further, the passage cross-sectional area of the inflow chamber 25 is formed so that the downstream portion 25b is smaller than the upstream portion 25a.

The right side wall 6W of the inflow chamber 25 is on the left side of the speed reducer cover 7 in the axial direction of the rotation shafts 11 and 15 with respect to the right side wall 6W below the inflow chamber 25 (specifically, the right side wall 6W below the communication portion 25c). It is recessed on the wall 7W side (reducer room 13 side). That is, the internal space of the inflow chamber 25 is expanded in the axial direction.

In other words, the right side wall 6W located below the communication portion 25c bulges toward the left side wall 5W side of the left case 5 in the axial direction of the rotating shafts 11 and 15 with respect to the right side wall 6W on the upstream portion 25a side of the inflow chamber 25. I'm out. This bulge is continuous up to the outlet 6a, and the outlet 6a is kept away from the sprocket 15A and the chain 16 so that the movement of the chain 16 and the like does not hinder the outflow of the lubricating oil to the speed reducer chamber 13 side. The return port 6b adjacent to the outflow port 6a protrudes toward the sprocket 15A and the chain 16 from the outflow port 6a, and the lubricating oil can be sent to the return port 6b by the movement of the chain 16 and the like.

Next, the action will be described.
The lubricating oil scraped up by the final driven gear of the differential device is introduced into the first oil gutter portion 22A of the right oil gutter 22, and then passed from the first oil gutter portion 22A to the second oil gutter portion 22B to the first of the left oil gutter 23. It is introduced into the oil gutter portion 23A of the above.

The lubricating oil introduced into the first oil gutter portion 23A is guided from the second oil gutter portion 23B to the inflow port 5a through the notch 5g.

The lubricating oil guided from the second oil gutter portion 23B to the inflow port 5a through the notch 5g flows into the connection chamber 18 from the inflow port 5a.

The lubricating oil that has flowed into the connection chamber 18 from the inflow port 5a is distributed into the lubricating oil that flows into the upstream portion 25a of the inflow chamber 25 and the lubricating oil that flows down into the shaft chamber 27 by the force flowing in the axial direction of the rotating shaft 15. .. The lubricating oil flowing down into the shaft chamber 27 collides with the rotating shaft 11 and flows from the opening end 15c into the spline fitting portion 17 (through hole 15B) to lubricate the spline. Further, the lubricating oil flowing down into the shaft chamber 27 lubricates the ball bearings 14A and 14B, as will be described later.

The lubricating oil that has flowed into the upstream portion 25a of the inflow chamber 25 is along the inflow chamber 25 without being affected by the rotation of the rotating shafts 11 and 15 (rotation of the spline fitting portion 17) by the peripheral wall portion 6m of the partition wall 6E. After flowing from the upstream portion 25a toward the downstream portion 25b, it flows into the shaft chamber 27 through the communication portion 25c.

The lubricating oil that has flowed from the inflow chamber 25 into the shaft chamber 27 flows down along the inner surface of the inner fitting portion 6D, collides with the protrusion 6d protruding upward from the lower end of the inner fitting portion 6D, changes the flow, and flows. It flows into the speed reducer chamber 13 so as to be pushed out from the outlet 6a into the speed reducer chamber 13. The lubricating oil that has flowed into the speed reducer chamber 13 lubricates the sprocket 15A, the chain 16, and the like. The lubricating oil that flows directly from the inflow port 5a into the shaft chamber 27 goes around with the rotation of the rotating shafts 11 and 15 (rotation of the spline fitting portion 17), and becomes the lubricating oil that has flowed from the inflow chamber 25 into the shaft chamber 27. With the momentum of the flow, it collides with the protrusion 6d together with the lubricating oil that has flowed from the inflow chamber 25 into the shaft chamber 27.

The inner diameter of the opening 5h of the left wall 5W of the left case 5 of this embodiment is formed to be smaller than the outer diameter of the ball bearing 14A. Further, the opening 5h and the ball bearing 14A are formed and arranged coaxially. As a result, the height of the lower end of the opening 5h of the left wall 5W is higher than the height of the lower end of the inner diameter of the outer ring of the ball bearing 14A.

Therefore, the lubricating oil that has flowed into the shaft chamber 27 is blocked by the opening 5h of the left side wall 5W, and is prevented from passing through the ball bearing 14A and returning to the transmission chamber 9. Then, until the lubricating oil accumulates higher than the lower end of the opening 5h of the left side wall 5W, the lubricating oil can be reliably flowed into the speed reducer chamber 13 side through the outlet 6a.

Therefore, the lubricating oil that has flowed into the shaft chamber 27 flows into the speed reducer chamber 13 side more than the transmission chamber 9. As a result, the lubricating oil for lubricating the sprocket 15A and the chain 16 can be efficiently introduced into the speed reducer chamber 13.

Further, if a large amount of the lubricating oil that has flowed into the shaft chamber 27 is accumulated, it will be carried around to the spline fitting portion 17, so that the stirring resistance of the rotating shafts 11 and 15 may increase, but the lubricating oil that has flowed into the shaft chamber 27 may increase. Collides with the protrusion 6d protruding upward from the inner fitting portion 6D, changes the flow, and is pushed out from the outflow port 6a into the speed reducer chamber 13. Alternatively, the lubricating oil that collides with the protrusion 6d and changes its flow flows in the axial direction and is discharged from the ball bearings 14A and 14B to the outside of the connection chamber 18.

Therefore, it is possible to prevent the lubricating oil from being carried around to the downstream side of the spline fitting portion 17 in the rotation direction with respect to the protrusion 6d, that is, to the return chamber 26 side of FIG. The amount of lubricating oil that goes around can be reduced, and the stirring resistance of the rotating shafts 11 and 15 can be reduced.

Further, a large amount of lubricating oil that goes around the spline fitting portion 17 becomes a fixed amount of oil film that fills the gap between the peripheral wall portion 6 m and the rotating shafts 11 and 15. Therefore, the amount of lubricating oil flowing down from the inflow port 5a to the spline fitting portion 17 is reduced, the amount of lubricating oil flowing into the inflow chamber 25 is increased, and the amount of lubricating oil flowing from the inflow chamber 25 into the shaft chamber 27 is increased. You can do a lot.

On the other hand, a part of the lubricating oil that flows down from the inflow port 5a and flows into the shaft chamber 27 is supplied to the inside of the spline hole 15b through the opening end 15c of the spline hole 15b, and is supplied to the inside of the spline hole 15b. While lubricating the inner peripheral spline 15s, it flows into the speed reducer chamber 13 through the through hole 15B.

The lubricating oil that has flowed down from the inflow port 5a and has flowed into the shaft chamber 27 flows to the left in the shaft chamber 27 along the axial direction of the spline fitting portion 17. The lubricating oil flowing to the left along the axial direction of the spline fitting portion 17 lubricates the ball bearing 14B, passes through the ball bearing 14B, and flows into the speed reducer chamber 13.

Similarly, the lubricating oil flowing down from the inflow port 5a and flowing to the right along the axial direction of the spline fitting portion 17 in the shaft chamber 27 passes through the ball bearing 14A and flows into the transmission chamber 9. Lubricate the ball bearing 14A.

On the other hand, the lubricating oil that has flowed into the speed reducer chamber 13 raises the oil level of the lubricating oil in the speed reducer chamber 13. A return port 6b is formed on the right side wall 6W of the speed reducer case 6, and the return port 6b is formed in the return chamber 26 separated from the inflow chamber 25 by the partition wall 6E. The return port 6b faces the chain 16 in the axial direction of the rotating shaft 15 and extends in the vertical direction along the inner surface of the inner fitting portion 6D.

As a result, the lubricating oil that goes around the chain 16 efficiently flows into the return port 6b as the chain 16 orbits around. The lubricating oil that has flowed into the return port 6b is returned from the return chamber 26 to the transmission chamber 9 through the return port 5b formed on the left side wall 5W of the left case 5.

The return chamber 26 is separated from the shaft chamber 27 by the partition wall 6E, and the lubricating oil that has flowed into the return chamber 26 from the return port 6b is affected by the rotation of the rotating shafts 11 and 15 (spline fitting portion 17). Instead, it is returned to the transmission chamber 9 from the return port 5b.

Further, since the lubricating oil that has flowed into the shaft chamber 27 collides with the protrusion 6d that protrudes upward from the inner fitting portion 6D and is prevented from being taken to the return chamber 26 side with respect to the protrusion 6d, the return port It is possible to prevent the flow of the lubricating oil flowing from 6b through the return chamber 26 to the return port 5b from being obstructed by the flow of the lubricating oil flowing through the shaft chamber 27. Therefore, the lubricating oil can be smoothly returned from the speed reducer chamber 13 to the transmission chamber 9.

The transmission chamber 9 has a larger volume than the speed reducer chamber 13, and contains a larger amount of lubricating oil than the amount of lubricating oil contained in the transmission chamber 9. As a result, the lubricating oil that has become hot in the speed reducer chamber 13 is returned from the speed reducer room 13 to the transmission room 9 and cooled by the lubricating oil housed in the transmission room 9.

Next, the effect of the transmission 1 of this embodiment will be described.
In the transmission 1 of the present embodiment, the left case 5 having the left side wall 5W, the speed reducer case 6 having the right side wall 6W facing the left side wall 5W, and the outer peripheral spline 11s are formed on the left end portion 11f, and the outer peripheral spline 11s is formed. Has a rotating shaft 11 supported by the left wall 5W via a ball bearing 14A so as to project from the left wall 5W toward the right wall 6W.

Further, the transmission 1 has a spline hole 15b in which an inner peripheral spline 15s fitted to the outer peripheral spline 11s is formed at the right end portion 15r, and the inner peripheral spline 15s protrudes from the right side wall 6W to the left side wall 5W side. As described above, it has a rotating shaft 15 supported by the right side wall 6W via a ball bearing 14B.

Further, the transmission 1 is provided on the left side wall 5W and the right side wall 6W so as to surround the outer peripheral spline 11s and the inner peripheral spline 15s, and the outer fitting portion 5C and the inner fitting portion 5C connecting the left side wall 5W and the right side wall 6W. It has a joint 6D.

The space surrounded by the left side wall 5W, the right wall 6W, the outer fitting portion 5C, and the inner fitting portion 6D is a connection chamber in which the spline fitting portion 17 into which the outer peripheral spline 11s and the inner peripheral spline 15s are fitted is installed. It constitutes 18.

The left wall 5W of the left case 5 has an inflow port 5a for allowing lubricating oil to flow from the transmission chamber 9 of the left case 5 into the connection chamber 18. In addition to this, the spline hole 15b has an opening end 15c facing the left side wall 5W, which is located below the inflow port 5a.

As a result, the lubricating oil guided from the oil gutter 21 through the notch 5g to the inflow port 5a flows into the connection chamber 18 (shaft chamber 27) from the inflow port 5a, passes through the opening end 15c of the spline hole 15b, and enters the inside of the spline hole 15b. Can be supplied.

Therefore, the outer peripheral spline 11s of the rotating shaft 11 and the inner peripheral spline 15s of the rotating shaft 15 can be lubricated with the lubricating oil, and the lubrication performance of the spline fitting portion 17 can be improved. As a result, it is possible to prevent the spline fitting portion 17 from being worn, and it is possible to improve the durability of the spline fitting portion 17.

Further, according to the transmission 1 of the present embodiment, the shaft length of the rotating shaft 15 is formed to be shorter than the shaft length of the rotating shaft 11. In addition to this, the rotating shaft 15 has a through hole 15B penetrating in the axial direction, and the left side wall 5W side of the through hole 15B constitutes a spline hole 15b on which an inner peripheral spline 15s is formed.

As a result, a part of the through hole 15B that penetrates the rotating shaft 15 in the axial direction can be configured as a spline hole 15b in which the inner peripheral spline 15s is formed. Therefore, the lubricating oil introduced into the spline hole 15b from the opening end 15c of the rotating shaft 15 can be discharged from the opening end 15d of the through hole 15B that opens to the left end portion 15f of the rotating shaft 15.

Therefore, the lubricating oil can be smoothly circulated through the spline holes 15b, and the lubricating performance of the spline fitting portion 17 can be improved more effectively.

Further, according to the transmission 1 of the present embodiment, the speed reducer cover 7 has a left side wall 7W opposite to the left side wall 5W with respect to the right side wall 6W of the speed reducer case 6.

In addition to this, the rotating shaft 15 has an oil channel 24 at the opening end 15d of the through hole 15B facing the left side wall 7W to guide the lubricating oil to the through hole 15B.

As a result, the lubricating oil flowing down along the left side wall 7W of the speed reducer cover 7 can be introduced into the through hole 15B by the oil channel 24.

Specifically, after moving upward along with the chain 16, the lubricating oil that has flowed down along the left side wall 7W of the speed reducer cover 7 is introduced from the notch formed in the upper part of the bearing support portion 7B to the left side wall 7W. It can be introduced into the gap between the disk portion 24A and the tubular portion 24B and introduced into the through hole 15B.

Therefore, the lubricating oil introduced into the through hole 15B can supply the lubricating oil to the spline fitting portion 17 from the opening end 15d of the through hole 15B in addition to the opening end 15c of the spline hole 15b. As a result, the lubrication performance of the spline fitting portion 17 can be improved more effectively.

Further, according to the transmission 1 of the present embodiment, the left wall 5W of the left case 5 has an inflow port 5a for flowing lubricating oil from the transmission chamber 9 of the left case 5 into the connection chamber 18, and the speed reducer case. The right side wall 6W of No. 6 has an outflow port 6a for flowing lubricating oil from the connection chamber 18 to the speed reducer case 6.

As a result, the transmission chamber 9 formed inside the left case 5 can communicate with the connection chamber 18 through the inflow port 5a. In addition to this, the speed reducer chamber 13 formed inside the speed reducer case 6 and the speed reducer cover 7 can communicate with the lower part of the connection chamber 18 through the outlet 6a. Therefore, the transmission chamber 9 and the reduction gear chamber 13 can communicate with each other via the connection chamber 18.

Therefore, the lubricating oil can be circulated between the transmission chamber 9 and the reduction gear chamber 13 through the connection chamber 18, and the ball bearings 14A housed in the transmission chamber 9 and the ball bearings 14B and 14C housed in the reduction gear chamber 13 can be circulated. , The sprocket 15A and the chain 16 can be lubricated with the same lubricating oil.

As a result, it is not necessary to individually manage the lubricating oils contained in the separate cases as in the conventional case, and the lubricating oils contained in the transmission chamber 9 and the speed reducer chamber 13 can be managed in one operation. It can be replaced at the same time, and the workability of the maintenance work of the transmission 1 can be improved.

Further, according to the transmission 1 of the present embodiment, the left wall 5W of the left case 5 has a return port 5b for communicating the connection chamber 18 and the transmission chamber 9 inside the left case 5, and the speed reducer case. The right side wall 6W of 6 has a return port 6b that communicates the connection chamber 18 with the speed reducer case 6 and the speed reducer room 13 inside the speed reducer cover 7, and the wall surface 6w of the right side wall 6W to the left side wall 5W of the left case 5. It has a partition wall 6E protruding from the surface.

The connection chamber 18 is divided into an inflow chamber 25 and a return chamber 26 by a partition wall 6E, and the inflow chamber 25 communicates with the transmission chamber 9 via the inflow port 5a and via the outflow port 6a. It communicates with the speed reducer room 13.

The return chamber 26 communicates with the transmission chamber 9 via the return port 5b and also communicates with the speed reducer chamber 13 via the return port 6b.

As a result, the transmission chamber 9 and the speed reducer chamber 13 can communicate with each other via the inflow chamber 25, and the transmission chamber 9 and the speed reducer chamber 13 can communicate with each other via the return chamber 26 partitioned from the inflow chamber 25.

Therefore, the lubricating oil can be circulated between the transmission chamber 9 and the reduction gear chamber 13, and the lubricating oil can be exchanged between the transmission chamber 9 and the reduction gear chamber 13.

Here, if the lubricating oil is independently contained in the transmission chamber 9 and the reduction gear chamber 13 and the lubricating oil cannot be circulated between the transmission chamber 9 and the reduction gear chamber 13, the lubricating performance and the lubricating oil are not circulated. It is necessary to set the amount of lubricating oil accommodated in the transmission chamber 9 and the reduction gear chamber 13 in consideration of durability against temperature rise.

Specifically, the reduction gear chamber 13 has a smaller capacity than the transmission chamber 9, and the amount of lubricating oil contained in the reduction gear chamber 13 is smaller than the amount of lubricating oil contained in the transmission chamber 9. Therefore, the temperature of the lubricating oil contained in the speed reducer chamber 13 tends to rise relative to the lubricating oil stored in the transmission chamber 9, and the lubricating oil deteriorates at an early stage to ensure the durability of the lubricating oil. Decreases. As a result, the lubrication performance of the lubricating oil deteriorates.

In order to suppress the temperature rise of the lubricating oil contained in the speed reducer chamber 13, it is necessary to increase the amount of lubricating oil contained in the speed reducer chamber 13, but if the amount of lubricating oil is increased, the sprocket 15A or the chain The stirring resistance of 16 increases.

In the transmission 1 of the present embodiment, the lubricating oil can be circulated between the transmission chamber 9 and the reduction gear chamber 13, and the lubricating oil is efficiently exchanged between the transmission chamber 9 and the reduction gear chamber 13. Therefore, the lubricating oil returned from the speed reducer chamber 13 to the transmission chamber 9 can be cooled by the lubricating oil contained in the transmission chamber 9.

Therefore, it is possible to suppress an increase in the temperature of the lubricating oil, prevent the lubricating oil from deteriorating at an early stage, and prevent the durability of the lubricating oil from deteriorating. As a result, it is possible to prevent the lubricating performance from being deteriorated by the lubricating oil.

In addition to this, since it is not necessary to increase the amount of lubricating oil contained in the speed reducer chamber 13, it is possible to prevent the stirring resistance of the sprocket 15A and the chain 16 from increasing.
As described above, in the transmission 1 of the present embodiment, the amount of lubricating oil contained in the transmission case 3 can be set to the optimum amount of lubricating oil.

Further, according to the transmission 1 of the present embodiment, the partition wall 5D and the partition wall 6E extend in the circumferential direction of the rotating shaft 11 so as to surround the spline fitting portion 17, and the connection chamber 18 is the partition wall 6E. There is a shaft chamber 27 that communicates with the inflow port 5a via the communication portion 25c between the inside of the spline fitting portion 17 and the spline fitting portion 17.

In addition to this, the inflow port 5a faces the upstream portion 25a of the inflow chamber 25 in the axial direction of the rotating shaft 11, and the partition wall 5D below the inflow port 5a is cut out so that the inflow port 5a is more than the inflow port 5a. It communicates with the shaft chamber 27 located below.

As a result, the lubricating oil flowing from the transmission chamber 9 into the connection chamber 18 through the inflow port 5a can be distributed to the inflow chamber 25 and the shaft chamber 27.

Specifically, when the amount of lubricating oil flowing from the inflow port 5a into the connection chamber 18 is small, the lubricating oil flows down from the inflow port 5a and is introduced into the shaft chamber 27 to lubricate the spline fitting portion 17 and at the same time. Lubricating oil can be poured from the shaft chamber 27 into the reduction gear chamber 13 through the outlet 6a.

Further, when the amount of lubricating oil flowing into the connection chamber 18 from the inflow port 5a is large, the lubricating oil is rectified by flowing the lubricating oil into the inflow chamber 25 and flowing from the upstream portion 25a to the downstream portion 25b of the inflow chamber 25. It can be poured into the speed reducer chamber 13 from the communication portion 25c through the shaft chamber 27 and the outflow port 6a.

Further, according to the transmission 1 of the present embodiment, the inflow chamber 25 extends from the upstream portion 25a side facing the inflow port 5a to the communication portion 25c on the downstream portion 25b side in the circumferential direction of the rotating shaft 11. The passage cross-sectional area of the inflow chamber 25 is smaller on the downstream portion 25b side than on the upstream portion 25a side.

As a result, the flow velocity of the lubricating oil flowing through the inflow chamber 25 can be increased from the upstream portion 25a toward the downstream portion 25b and flowed from the communication portion 25c into the shaft chamber 27, so that the flow of the lubricating oil can be smoothed. Further, the communication portion 25c is arranged on the rear side of the rotating shafts 11 and 15, and it is possible to prevent the lubricating oil flowing down from the communicating portion 25c from directly falling on the rotating shafts 11 and 15.

Therefore, more lubricating oil can be sent from the inflow chamber 25 to the reduction gear chamber 13 through the outflow port 6a.

Further, the right side wall 6W on the upstream portion 25a side of the inflow chamber 25 is on the left side wall 7W side (deceleration) of the speed reducer cover 7 in the axial direction of the rotating shafts 11 and 15 with respect to the right side wall 6W on the downstream portion 25b side of the inflow chamber 25. It is dented in the cabin 13 side).

As a result, the volume on the downstream portion 25b side can be made smaller than the volume on the upstream portion 25a side of the inflow chamber 25, and the flow velocity of the lubricating oil flowing through the inflow chamber 25 becomes higher as it goes from the upstream portion 25a to the downstream portion 25b. can.

Further, in the transmission 1 of the present embodiment, a minute gap is formed between the partition wall 5D of the left side wall 5W of the left case 5 and the partition wall 6E of the right side wall 6W of the speed reducer case 6 in the axial direction of the rotating shafts 11 and 15. They are facing each other through. As a result, when the speed reducer case 6 and the speed reducer cover 7 are integrally fastened to the left case 5 by the bolt 10, it is possible to prevent the mounting from being hindered.

Specifically, when the partition wall 5D and the partition wall 6E are in close contact with each other, the reduction gear case 6 is fastened when the reduction gear case 6 and the reduction gear cover 7 are integrally fastened to the left case 5 by bolts 10. There is a possibility that the speed reducer case 6 or the speed reducer cover 7 may be deformed due to a gap between the portion and the fastening portion of the left case 5, which may cause a problem.

On the other hand, when the partition wall 5D and the partition wall 6E face each other through a minute gap in the axial direction of the rotating shafts 11 and 15, the fastening portion of the speed reducer case 6 and the fastening portion of the left case 5 have no gap. The speed reducer case 6 can be fastened to the left case 5 in the abutted state. As a result, it is possible to provide a margin at the time of assembling, and it is possible to improve the assembling accuracy of the speed reducer case 6 and the left case 5.

Further, in the work of forming the outer fitting portion 5C on the left side wall 5W of the left case 5 with a cutting tool, cutting is performed from the speed reducer case 6 side to process the inner diameter of the outer fitting portion 5C, and the outer fitting portion 5C is divided by the same cutting tool. The top surface of the wall 5D (opposing surface of the partition wall 6E) is processed.

That is, the inner diameter of the outer fitting portion 5C can be machined and the top surface of the partition wall 5D can be machined at the same time with a cutting tool.

Although the embodiments of the present invention have been disclosed, it is clear that some skilled in the art can make changes without departing from the scope of the present invention. All such modifications and equivalents are intended to be included in the following claims.

1 ... Transmission (power transmission device), 5 ... Left case (first case), 5a ... Inlet, 5W ... Left wall (first wall), 6 ... Reducer case (second case), 6D ... inner fitting part (connection part), 6W ... right side wall (second wall part), 7 ... reducer cover (second case) , 7W ... left wall (third wall), 11 ... rotation axis (first rotation axis), 11f ... left end (one end of first rotation axis), 11s ... Outer spline, 14A, 14B ... ball bearing (bearing), 15 ... rotating shaft (second rotating shaft), 15B ... through hole, 15b ... spline hole, 15c ... open end ( Spline hole open end), 15d ... Open end (open end of through hole), 15r ... Right end (one end of second rotation shaft), 15s ... Inner circumference spline, 17 ... Spline fitting part, 18 ... connection chamber, 24 ... oil channel (fueling member)

Claims (3)

A first case with a first wall and
A second case having a second wall portion facing the first wall portion, and a second case.
A first rotation in which an outer peripheral spline is formed at one end and is supported by the first wall portion via a bearing so that the outer peripheral spline projects from the first wall portion toward the second wall portion. Axis and
A bearing is provided at one end so as to have a spline hole in which an inner peripheral spline fitted to the outer peripheral spline is formed, and the inner peripheral spline projects from the second wall portion toward the first wall portion. A second rotating shaft supported by the second wall portion via the second rotating shaft,
A connecting portion provided on the first wall portion and the second wall portion so as to surround the outer peripheral spline and the inner peripheral spline, and connecting the first wall portion and the second wall portion. It is a power transmission device that has
The space surrounded by the first wall portion, the second wall portion, and the connection portion constitutes a connection chamber in which the spline fitting portion into which the inner peripheral spline and the inner peripheral spline are fitted is installed. death,
The first wall portion has an inflow port for lubricating oil to flow into the connection chamber from the inside of the first case.
The spline hole has an open end facing the first wall portion.
A power transmission device characterized in that the open end is located below the inflow port. The shaft length of the second rotating shaft is formed shorter than the shaft length of the first rotating shaft.
The second rotating shaft has a through hole penetrating in the axial direction of the second rotating shaft, and the first wall side of the through hole forms the spline hole on which the inner peripheral spline is formed. The power transmission device according to claim 1, wherein the power transmission device is configured. The second case has a third wall portion on the side opposite to the first wall portion with respect to the second wall portion in the axial direction of the second rotation axis.
The power transmission according to claim 2, wherein the second rotating shaft has a lubrication member for guiding lubricating oil to the through hole at an open end of the through hole facing the third wall portion. Device.

Images