JPS637736Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a lubricating oil passage structure of a transmission employed in two-wheeled motor vehicles and the like.

(Prior Art) Fig. 1 is a partial cross-sectional view of a vertical cross-section of a transmission of a conventional two-wheeled motor vehicle, viewed from the rear.
As shown in Fig. 1, in the conventional product, the crankcase 1
Inside the transmission case, an inlet passage 2, a connecting passage 3, and an outlet passage 4 for lubricating oil are provided by cast holes. Passage 2 is crankcase 1
The inlet is connected to a passage on the oil pump side (not shown). The passage 3 is provided inside the peripheral wall 6 of the crankcase 1 and connects the outlet of the passage 2 and the entrance of the passage 4. It is provided inside the other side wall 7 of the passage 4, and oil is supplied from the passage 4 to the gear train 9 of the transmission and the like via another lubricating oil passage 8.

However, when the passage 3 is formed by a casting hole as described above, it is necessary to use a very long casting pin to form the passage 3 when die-casting the crankcase 1, which causes a problem in the durability of the pin. Furthermore, since the entire passages 2, 3, and 4 are longer, there is a greater risk of oil leakage due to blowholes. Since the longer passage 3 is provided in the peripheral wall 6, the wall thickness of the peripheral wall 6 increases, which is disadvantageous in terms of weight and cost. Passage 2, 3, 4
Installation requires drilling holes or using blind plugs in many locations, which increases the risk of oil leakage and increases costs. Moreover, if the passage 3 is provided inside the peripheral wall 6 as shown in FIG. 2, which is a partial view of FIG. do.

(Purpose of the invention) The object of the invention is to install a pipe in the internal space of a transmission case and form a connecting passage for lubricating oil by the pipe, thereby solving the above-mentioned conventional problems.

(Structure of the invention) The present invention provides an inlet side lubricating oil passage inside one side wall of a transmission case that has a pair of side walls and a peripheral wall continuous to the edges of both side walls. An outlet side lubrication passage is provided inside, a connecting passage connecting both passages is formed by a pipe, the pipe is arranged in an internal space surrounded by the peripheral wall and the side wall, and a large end with a closed tip is provided at one end of the pipe. A diameter portion is provided, the large diameter portion is fitted into a through hole provided in the one side wall, the inlet side lubricating oil passage is opened on the inner peripheral surface of the through hole, and the inlet side lubricating oil passage is provided in the large diameter end. A hole having a diameter different from the opening of the lubricating oil passage is provided in communication with the opening, an opening is formed at the tip of the other end of the pipe, a hole having a bottom is provided in the other side wall, and a hole is provided in the middle of the hole. The other end of the pipe is fitted to the bottom of the hole to form a bottom space through which the tip opening of the other end communicates, and the outlet side lubricating oil passage communicates with the bottom space. .

(Embodiment) FIG. 3 is a partial cross-sectional view of a vertical cross-section of a transmission employing the present invention, viewed from the rear. As shown in Fig. 3, the crankcase 10 of a motorcycle
(transmission case) has a pair of side walls 12 and 13 surrounding an internal space 11 of the transmission.
and a surrounding wall 14 are integrally provided. A drive shaft 16 of the transmission extends in the vehicle width direction and is supported by the inner circumferences of holes 17 and 18 in side walls 12 and 13 via a ball bearing 19 and a needle bearing 20, respectively. A plurality of gears 21 are attached around the drive shaft 16 between both bearings 19 and 20. The peripheral wall 14 includes a large-diameter cylindrical portion 22 that extends to the right in the vehicle width direction than the side wall 12, and a clutch (not shown) is housed inside the cylindrical portion 22. The side wall 13 is provided with a boss 23 projecting leftward in the vehicle width direction around the hole 18, and a cover 25 is attached to the tip of the boss 23. A gear shift operation mechanism (not shown) is housed inside the cover 25.

A pipe 27 forming a connecting passage 26 for lubricating oil is installed within the interior space 11 . The pipe 27 extends above the drive shaft 16 in parallel with the drive shaft 16, and both ends 28 and 29 are connected to the side wall 1, respectively.
The holes 30 and 31 (holes) provided in the holes 2 and 13 are press-fitted and fixed. The hole 31 is open only to the internal space 11 side, whereas the hole 30 penetrates the side wall 12. Therefore, during assembly, the pipe 27 is inserted into the hole 3 from inside the cylindrical portion 22, with the end 29 leading.
In order to simplify the insertion work, the pipe 27 is designed as follows. That is, the end portion 28 is the most distal portion 3
3 has a slightly larger diameter than the other parts,
When inserting the pipe 27, the pipe 2 is inserted until the large diameter portion 33 enters the hole 30 (almost to the end of the insertion process).
7 can be inserted easily (lightly). In addition, micro holes 34 are provided at several locations on the pipe 27,
It is also possible to supply oil from the hole 34 to some of the gears 21 or to the shift fork fitting groove 49 of the gear 21.

The side wall 12 is provided with a cylindrical boss 35 around the hole 30 that protrudes toward the inside of the cylindrical portion 22 . A lubricating oil inlet passage 36 is provided in the boss 35 at the portion where the large diameter portion 33 fits, and the passage 36 opens to the inner periphery of the hole 30 . The large diameter portion 33 of the pipe 27 has a closed end and is provided with a small diameter hole 37 (orifice), and the passage 36 communicates with the passage 26 via the hole 37.

A hole 31 in the opening of the other end 29 of the pipe 27 communicates with a bottom space 39 . A lubricating oil outlet passage 41 is formed inside the boss 40 of the side wall 13 . The passage 41 generally extends vertically, and has an upper end connected to the bottom space 39 and a lower end communicated with an annular groove 42 on the inner circumferential surface of the boss 23 . A cup-shaped outer race 43 is fitted into the inner periphery of the boss 23. The outer race 43 is a member for holding the outer periphery of the bearing 20, and is provided with a small diameter hole 44, and the groove 42 is connected to a gap 45 inside the outer race 43 via the hole 44. The drive shaft 16 has a cylindrical shape, and has a lubricating oil passage 4 inside.
6, and the gap 45 communicates with the passage 46. A plurality of radial holes 47 are provided in the drive shaft 16 , and the passage 46 communicates with the inner periphery of the gear 21 via the holes 47 . The right end portion (not shown) of the passage 46 is connected to a portion requiring lubrication, such as a clutch bearing portion.

As shown in FIG. 4, which is a partial view of FIG.
An inlet (lower part) of the passage 36, not shown, is connected to an oil pump via an oil filter or the like.

(Function) During engine operation, oil is supplied from the oil pump to the passage 36 through the filter. This oil flows from the passage 36 through the hole 37 shown in FIG. 3 to the passage 2.
6, flows from the passage 26 to the passage 46 via the passage 41, groove 42, hole 44, gap 45, and
6 to the clutch etc., and the hole 47
It is supplied to the gear 21 through. In addition, if the pipe 27 is provided with a fine hole 34, the oil also flows from the hole 34 to the gear 21 and the shift fork fitting groove 49.
supplied to

(Effect of the invention) According to the structure of the invention explained above, the side wall 12
Inlet side passage 36 inside and outlet side passage 4 inside side wall 13
1 is formed by a pipe 27 installed in the internal space 11, and the passage in the peripheral wall 14 is eliminated, so the following advantages can be obtained. That is, when die-casting the crankcase 10, there is no need to use long pins to form passages in the peripheral wall 14, so the labor and cost of die-casting can be reduced. Since there is no need to form a long casting passage in the crankcase 10, there is no fear of oil leakage due to casting cavities. Since there is no need to form a thick boss forming the peripheral wall of the passage on the peripheral wall 14, the weight and cost of the crankcase 10 can be reduced. The total length of the passage within the wall thickness is shortened, and the number of passage bends is also reduced, so the number of man-hours for drilling holes and the number of blind plugs are reduced, which also increases reliability against oil leakage. Cost can be reduced. As shown in Figure 4, the passage 36 is connected to the surrounding wall 1.
It is not necessary to extend the passage 36 to the hole 17, but it is sufficient to extend the passage 36 to the hole 30 slightly above the hole 17.
Even when used alone, processing can be simplified and the weight of the oil passage boss can be reduced. Furthermore, in the present invention, the large diameter portion 33 of the closed structure provided at one end (base end) of the pipe 27 is fitted into the through hole 30 of the side wall 12, and the other end 29 of the pipe 27 is fitted into the through hole 30 of the side wall 12.
It is adapted to be fitted into a bottomed hole 31 (hole).

In this structure, in the pipe assembly work, the pipe 27 is inserted from the hole 30 side to the hole 29 side with the other end 29 at the beginning, but in this work, the large diameter portion 33 and the other end 29 are Until it is fitted into the corresponding hole 30 and hole 31,
(In other words, until the final stage of the pipe insertion process), the pipe 27 is not press-fitted into the inner periphery of the hole 30, and therefore, the pipe 27 can be easily inserted until the final stage. be able to.

Furthermore, since the end 33 of the pipe 27 is located in the through hole 30, the relative position of the end 33 and the through hole 30 is visually checked to accurately set the longitudinal position of the pipe 27. be able to.

In this manner, the present invention allows the pipe 27 to be assembled and positioned accurately in the longitudinal direction.

Furthermore, in the present invention, an opening is formed at the tip of the tip (other end 29) of the pipe 27, a hole 31 (hole) having a corresponding bottom surface of the side wall 13 is provided, and the pipe end is opened halfway into the hole 31. The part 29 is fitted to form a bottom space 39 in which the tip opening of the pipe end communicates with the bottom of the hole 31, and the outlet side lubricating oil passage 41 is communicated with the bottom space 39.

According to this configuration, there is no need to provide a communication hole in the tube wall (peripheral wall) of the pipe end 29 (the communication hole is required when the tip opening of the tip portion 29 contacts the bottom of the hole 31), and processing is simplified. can be converted into

Furthermore, as described above, since the longitudinal positioning of the pipe 27 is accurate, the tip of the pipe 27 can be reliably separated from the bottom of the hole 31 and the bottom space 39 (the communication passage between the pipe passage 26 and the wall passage 41 ) can be formed. That is, in the present invention, the above-mentioned large diameter portion 3
Since the pipe positioning technique according to No. 3 is adopted, it is possible to easily complete a passage connection structure that utilizes the bottom space.

Furthermore, if the bottom space 39 is abolished and a communication hole is provided in the peripheral wall of the pipe end 29, in order to make the hole communicate with the passage 41 (in the illustrated embodiment, in order to make the communication hole open downward). ), pipe 27
Although it is necessary to set the angular position accurately, the present invention does not require such positioning.

Angular positioning of the pipe 27 is necessary in order to communicate the hole 37 of the large diameter end 33 with the inlet passage 36, but the diameters of the hole 37 and the passage 36 are different, and in the embodiment, the diameter of the hole 37 and the passage 36 are different. 37 is a small diameter orifice, so even if some positioning error occurs,
To securely connect to a large diameter passage 36. Therefore, this positioning work is easy, and the assembly work is also simplified in this respect.

[Brief explanation of the drawing]

Figure 1 is a partial cross-sectional view of a conventional transmission seen from the rear, Figure 2 is a partial view of Figure 1 in the direction of the - arrow, and Figure 3 is a vertical cross-section of a transmission employing the present invention. FIG. 4 is a partial cross-sectional view of FIG. 3 viewed from the rear. 10... Crank case, 11... Internal space,
12, 13... side wall, 14... peripheral wall, 26... connecting passage, 27... pipe, 29... pipe end,
30... Through hole in the side wall, 31... Bottomed hole in the side wall,
33...Large diameter portion, 36...Inlet side passage, 37...
... Pipe hole, 39 ... Bottom space, 41 ... Outlet side passage.

Claims (1)

[Scope of utility model registration request] A transmission case having a pair of side walls and a peripheral wall continuous to the edges of both side walls, an inlet side lubricating oil passage provided inside one side wall, and an outlet side lubricating oil passage provided inside the other side wall, A connecting passage connecting both passages is formed by a pipe, the pipe is arranged in an internal space surrounded by the peripheral wall and the side wall, and a large diameter portion with a closed tip is provided at one end of the pipe, the large diameter portion is fitted into a through hole provided in one of the side walls, the inlet side lubricating oil passage is opened on the inner peripheral surface of the through hole, and the large diameter end has a diameter different from that of the inlet lubricating oil passage. A hole is provided in communication with the opening, an opening is formed at the tip of the other end of the pipe, a hole having a bottom is provided in the other side wall, and the other end of the pipe is fitted halfway into the hole. A lubricating oil passage for a transmission, characterized in that a bottom space is formed at the bottom of the hole to which the tip opening of the other end communicates, and the outlet side lubricating oil passage is communicated with the bottom space.