JP2000310214A - Oil feed passage structure of crankshaft - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce cost by communicating an oil reservoir mounted on an outside surface of a crank web which is adapted to feed oil to a crank pin with an oil feed passage connected to an oil pump by a groove which is worked extremely easily. SOLUTION: This structure comprises a side plate 71 to define an oil reservoir 61 communicating with a circumferential face of a crank pin 10p mounted on an outer end face of a crank web 10w. And the oil reservoir 61 and an oil feed passage 58, which is connected with an oil pump 32, are communicated by an oil groove 59 which is formed on the outer circumferential face of a crank journal 10j1 supported on a crank case 6 via a bearing 151.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lubricating passage structure for lubricating an outer peripheral surface of a crankpin of an engine crankshaft, and more particularly to an oil supply passage extending to an outer end surface of a crank web and an outer peripheral surface of the crankpin. The present invention relates to an improvement in a crankshaft oil supply passage structure in which a side plate defining a reservoir is attached, and a supply oil passage leading to an oil pump is connected to the oil reservoir.

[0002]

2. Description of the Related Art Such a lubricating passage structure for a crankshaft is already known, for example, as disclosed in Japanese Patent Publication No. 57-45460.

[0003]

In the oil supply passage structure described in the above publication, the oil sump is bent from the shaft end of the crankshaft to reach the oil sump in order to communicate the oil sump with the oil supply passage connected to the oil pump. The oil hole is machined.

[0004] Incidentally, since such a bent oil hole must be processed from two directions with a drill, a long processing time is required, which is one of the factors that hinders cost reduction.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and enables the oil reservoir and the supply oil passage to communicate with each other by a groove that is extremely easy to process, thereby contributing to cost reduction. It is an object of the present invention to provide a crankshaft oil supply path structure.

[0006]

In order to achieve the above object, according to the present invention, a side plate defining an oil sump communicating with an outer peripheral surface of a crank pin is attached to an outer end face of a crank web, and the oil sump is provided in the oil sump. And a supply oil passage communicating with an oil pump, the oil supply passage of the crankshaft, wherein the oil supply passage and the oil are provided through an oil groove formed on an outer peripheral surface of a crank journal supported by a crankcase via a bearing. The first feature is that communication is made between the pools.

According to the first feature, since the oil groove is easily formed on the outer peripheral surface of the crank journal, the communication between the supply oil passage and the oil reservoir can be easily achieved, and the productivity of the crankshaft can be reduced. The cost can be increased and the cost can be reduced.

The present invention is characterized in that, in addition to the first feature, the oil groove is formed parallel to the axis of the crank journal.

According to the second feature, the oil groove can be formed at the same time as the forging of the crankshaft, so that a special groove machining step is not required, thereby further increasing the productivity of the crankshaft. Can be.

Further, the present invention provides, in addition to the second feature,
A third feature is that the oil groove is arranged at a position that is out of phase with the crankpin by approximately 90 ° with respect to the rotation center of the crank journal.

According to the third feature, when the piston reaches the top dead center and the bottom dead center, the oil groove is located on a plane orthogonal to the axis of the cylinder bore, and the oil groove is located near the oil groove. It is possible to avoid the application of a vertical load, and to prevent a decrease in the strength of the clan journal due to the oil groove.

Further, according to the present invention, in addition to any one of the first to third features, the crank journal is formed so as to have a larger diameter than a journal outer shaft extending outward therefrom. An annular oil chamber is formed at an annular step between the outer shaft portions of the journals, and an opening of the oil groove is opened, and a crankcase supporting the bearing defines an annular oil chamber facing an outer surface of the bearing and an inlet of the oil groove. The fourth feature is that the supply oil passage is connected to the oil chamber.

According to this fourth feature, the bearing supporting the crank journal can be lubricated by the lubricating oil flowing from the supply oil passage into the annular oil chamber, and the lubricating oil in the annular oil chamber is reduced by centrifugal force. The oil can pass straight through the oil groove without going back, and lubrication to the crankpin can be performed smoothly.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on one embodiment of the present invention shown in the accompanying drawings.

FIG. 1 is a rear side view of a motorcycle to which the present invention is applied, FIG. 2 is a sectional view taken along line 2-2 of FIG. 1, and FIG.
3 is a sectional view taken along the line 4-4 in FIG. 3, FIG. 5 is a sectional view taken along the line 5-5 in FIG. 3, FIG. 6 is a sectional view taken along the line 6-6 in FIG. 8 is an enlarged view around the oil pump, and FIG.
FIG. 9 is an exploded perspective view of the crankshaft,
FIG. 10 is a perspective view of the lid.

First, in FIG. 1, a motorcycle 1 is of a scooter type, and a power unit P for driving a rear wheel Wr is attached to a rear portion of a body frame 2 via a link 9 so as to be vertically swingable. At the same time, a rear cushion 3 is interposed between the power unit P and the body frame 2.

As shown in FIG. 2, the power unit P comprises a water-cooled four-cycle engine 4 and a belt-type continuously variable transmission 5 coupled to the left side of the engine 4. A rear wheel Wr located immediately after the engine 4 is mounted on one side of the rear end.

2 to 4, an engine 4 includes a crankcase 6, a cylinder block 7 which is connected to a front surface of the crankcase 6, and is disposed substantially horizontally, and a cylinder which is joined to an upper surface of the cylinder block 7. The head 8 is the engine body, and the crankshaft 10 housed and supported in the crankcase 6 is a cylinder block 7.
Is connected via a connecting rod 12 to a piston 11 which moves up and down in the cylinder bore 7a.

The cylinder head 8 is provided with a known valve operating mechanism 74 including a camshaft 14 driven from the crankshaft 10 via a timing transmission 13, and an intake valve 72 and an exhaust valve 73 which are opened and closed thereby. (See FIG. 4).

The crankcase 6 includes a cylinder block 7
And a rear case half 6b bolted to the front case half 6a. The left and right crankshafts of the crankshaft 10 are interposed between the case halves 6a and 6b. Journal 10j ₁ , 10
j ₂ is clamped via ball bearings 15 ₁ and 15 ₂ , respectively. Of the crank shaft 10, the journal outer shaft portion 10e extending outwardly from the left crank journal 10j ₁ driven pulley 16 of the continuously variable transmission 5 is mounted, the transmission case 17 is a crank case 6
Bolted to the left end face of

At the right end of the crankcase 6 on the side opposite to the continuously variable transmission 5, a transmission chamber 18 in which the timing transmission device 13 is disposed, and a cylindrical auxiliary equipment chamber 1 adjacent to the outside thereof.
An oil seal 21 that is in close contact with the outer peripheral surface of the crankshaft 10 is mounted on a partition wall 20 between the transmission chamber 18 and the auxiliary equipment chamber 19.

As shown in FIGS. 3 and 5, in the accessory room 19, a plurality of bosses 19a projecting from the inner wall of the accessory room 19 are provided with a plurality of bolts 23 (see FIG. 5).
The rotor 22r is fixed to the right end of the crankshaft 10 with bolts 24.

An accessory room cover 25 and a fan cover 26 are sequentially joined to the right end of the crankcase 6, and a radiator 28 for cooling the engine is attached to the outer end of the fan cover 26. Machine 22
A cooling fan 27 for cooling the fan is provided in the fan cover 26. This cooling fan 27 is
Thus, the rotor 22r and the rotor 22r are fixed to the crankshaft 10.

As shown in FIGS. 3 and 4, the lower part of the crankcase 6 is formed in an oil reservoir 29, and the lubricating oil 30 stored therein is sucked into an oil pump 32 through an oil filter 31. The pressure is fed to the crankshaft 10 and other parts of the engine.

A lower part of the front case half 6a is formed with a cylindrical filter chamber 33 which is opened at the front surface thereof.
The oil filter 31 in a cup shape and a holding spring 35 for pressing a sealing member 34 attached to the open end of the oil filter 31 against the inner wall of the chamber 33 are accommodated in the opening 3. The cap 36 is screwed.

The filter chamber 33 is divided by the oil filter 31 into an unpurified chamber corresponding to the inside of the oil filter 31 and an outer purifying chamber, and an inlet oil passage 37 connected to the oil reservoir 29 is connected to the unpurified chamber. The suction port 32i of the oil pump 32 communicates with the purification chamber via an outlet oil passage 38.

When the cap 36 is removed, the oil filter 31 can be taken out and cleaned, and the lubricating oil 30 in the oil reservoir 29 can be discharged outside through the filter chamber 33. . Therefore, the cap 36 also serves as a drain bolt.

In FIG. 7, an oil pump 32 is mounted on the inner wall of the transmission chamber 18 opposite to the partition wall 20. The oil pump 32 includes a pump housing 40
A pump rotor 41 housed therein, and a pump cover 42 joined to an open surface of the pump housing 40.
The pump cover 42 has the suction port 3
2i and a discharge port 32o are provided. And
The pump housing 40 and the pump cover 42 are provided with bolts 4 on the inner wall of the transmission chamber 18 with the cover 42 inside.
3 fixed. The bearing hole 4 of the pump housing 40 is provided in the oval connection hole 44 of the pump rotor 41.
The pump shaft 46 penetrating through 5 is fitted and connected so as to be removable.

The boss 4 of the driven gear 48 is mounted on the pump shaft 46.
8a are fitted and connected via a joint pin 68. That is, as shown in FIG. 8, the joint pin 68 is attached to the pump shaft 46 so as to cross the pump shaft 46. The joint pin 68 engages with the key groove 69 on the end face of the boss 48a of the driven gear 48, so that the pump The shaft 46 and the driven gear 48 are connected.

The driven gear 48 is driven by the drive gear 47 fixed to the crankshaft 10 in the transmission chamber 18 and has a much larger diameter than the oil pump 32. The drive sprocket 49 of the timing transmission 13 is formed integrally with the drive gear 47.

In the partition wall 20, a circular mounting hole 50 having substantially the same diameter as the oil pump 32, that is, a diameter much smaller than that of the driven gear 48, is provided in a portion facing the oil pump 32. Through this mounting hole 50, the oil pump 32 can be attached and detached, in particular, the bolt 43 can be attached and detached.

A lid 52 is fitted into the mounting hole 50 via a seal member 53. A bag-shaped bearing hole 51 for rotatably supporting the outer end of the pump shaft 46 and restricting its axial movement is provided on the inner surface of the lid 52.
Is provided. As shown in FIG. 10, the lid 52 is integrally formed with a fan-shaped flange 54 protruding radially from the outer peripheral edge and a support 55 protruding from the outer surface. Is brought into contact with the partition wall 20 on the auxiliary equipment room 19 side, and the inner surface of the stator 22s is pressed against the tip of the support column 55 via the elastic cap 56 so that the lid 52 is positioned at the fixed position of the mounting hole 50. Will be retained.

The discharge port 32o of the oil pump 32 is
The supply oil passage 58 formed in the front case half 6a is
Rank Journal 10j₁Bearing ball bearing
Fifteen ₁Oil chamber 60 facing the outside surface of the left crank journal
Le 10j₁Oil groove 59 formed on the outer peripheral surface of the
Journal 10j₁Web 1
0w, oil reservoir 61 and crank pin 10p
And the radius provided on the crankpin 10p
Through the oil hole 63 in the direction
Communicate with the surrounding surface. The crankshaft in which the above-mentioned oil hole 63 is opened
The outer peripheral surface of the connecting rod 10p is the large end 12b of the connecting rod 12.
Is supported via a needle bearing 64 (see FIG. 4).
You.

The oil passage structure will be described in more detail.

The crankcase 6, the outer wall 65 of the continuously variable transmission 5 side, with the outer race of the ball bearing 15 ₁ which supports the left crank journal 10j ₁ are fitted closely to the journal outer shaft portion 10e The outer wall 65 and the oil seal 6 are attached.
The oil chamber 60 of the annular facing outer surface of the ball bearing 15 ₁ is defined by 6.

Left crank journal 10j₁Is that
The outer diameter of the journal extending outwardly is larger than that of the
Therefore, these left crank journals 1
0j ₁And the oil chamber between the journal outer shaft 10e.
An annular step 67 facing 60 is formed. This left crank
Journal 10j₁On the outer peripheral surface of the
Crank journal 10j₁The oil groove 5 reaching the root of
9 are provided, and these oil grooves 59 are opened to the step 67.
The mouth end is the entrance.

The oil groove 59 is formed when the crankshaft 10 is forged.
As is apparent from FIG. 9, the left crank journal ₁ is located at two places where the phase of the left crank rank journal 10j1 is shifted by about 90 ° with respect to the rotation center of the left crank rank journal 10j1.
It arranged parallel to the axis of 0j _1.

[0038] In addition, in the crank shaft 10, of the left crank journal 10j ₁ the same side crank web 1
The outer surface of 0w is formed a circular recess 70, this recess 70, is press-fitted an annular side plate 71 surrounding the left crank journal 10j _1, an annular between the the side plate 71 crank webs 10w The flat oil sump 61 is defined, the outlet of the oil groove 59 opens radially inward of the oil sump 61, and the hollow portion 62 of the crankpin 10p opens at an intermediate portion.

As shown in FIG. 6, the front case half 6a,
The cylinder block 7 and the cylinder head 8 are provided with a second oil supply passage 58 ′ branched from the oil supply passage 58, and the valve mechanism 74 is provided through the second oil supply passage 58.
Is to be refueled.

Next, the operation of this embodiment will be described.

In mounting the oil pump 32 and its drive system, first, in the front case half 6a before the rear case half 6b is connected, the oil pump 32 is inserted into the transmission chamber 18 and the auxiliary machine 19 The oil pump 32 is mounted at a predetermined position on the inner wall of the transmission chamber 18 by a bolt 43 inserted into the transmission chamber 18 through the mounting hole 50 from the bottom.

Next, a large-diameter driven gear 48 is inserted into the transmission chamber 18 of the front case half 6a so as to be adjacent to the oil pump 32. Then, the pump shaft 46 provided with the joint pin 68 is passed through the mounting hole 50 from the auxiliary machine room 19 side.
The boss 48a of the driven gear 48, the bearing hole 45 of the pump housing 40, and the connecting hole 44 of the pump rotor 41 are sequentially inserted into the boss 48a.
With the key groove 69 of the first embodiment.

Finally, a cover 52 having a seal member 53 mounted on the outer periphery is fitted into the mounting hole 50 of the partition wall 20, and the bearing hole 51 is fitted to the outer end of the pump shaft 46, 54 is brought into contact with the outer surface of the partition wall 20. In this state, the elastic cap 5 is attached to the tip of the support 55 of the lid 52.
Put 6 on.

Thus, even when the diameter of the mounting hole 50 of the partition wall 20 is smaller than that of the driven gear 48, the mounting of the oil pump 32 on the inner wall of the narrow transmission chamber 18 and the connection of the driven gear 48 to the pump shaft 46. Easy to do. Therefore, depending on the mounting hole 50 having a smaller diameter than the driven gear 48,
Since the strength of the partition wall 20 hardly decreases, it is advantageous for weight reduction.

In addition, the axial movement of the pump shaft 46 inserted through the driven gear 48, the pump housing 40 and the pump rotor 41 is regulated by the bag-shaped bearing hole 51 of the lid 52 fitted in the mounting hole 50. A member such as a clip dedicated to retaining the shaft 46 is not required, and the structure can be simplified.

The bearing hole 51 of the lid 52, together with the bearing hole 45 of the pump housing 40, supports the pump shaft 46 on both sides of the driven gear 48, so that the support is strengthened and the durability of the oil pump 32 is improved. Can be improved.

Thereafter, when the entire engine is assembled, the generator 2 fixed to the inner wall of the auxiliary machine room 19 of the crankcase 6
The second stator 22 s has its inner end face facing the support 55 of the lid 52.
Of the partition 52 through the elastic cap 56 so that the lid 52 separates the flange 54 from the partition 2.
Since the holding member is held at a fixed position in contact with the outer surface, no dedicated holding member such as a bolt is required, and the holding structure can be simplified. On the other hand, the drive gear 47 fixed to the crankshaft 10 meshes with the driven gear 48 to make the oil pump 32 drivable.

During operation of the engine 4, the crankshaft 1
The drive gear 47 rotating together with the zero drives the driven gear 48 in a reduced speed, so that the rotor 41 of the oil pump 32 is driven at an appropriate speed. Oil pump 32 operated in this manner
The lubricating oil 30 in the oil reservoir 29 is
And a supply oil passage 58, an oil chamber 60, an oil groove 59, a hollow portion 62 of a crank pin 10p, and an oil injection hole 63.
Because pumped into the ball bearing 15 ₁ which supports the left crank journal 10j ₁ in the oil chamber 60 to lubricate,
In the crank pin 10p, the outer peripheral surface, the needle bearing 64, and the inner peripheral surface of the large end 12b of the connecting rod 12 can be lubricated.

[0049] At that time, the inlet of the oil groove 59, because they open the annular step 67 between the left crank journal 10j ₁ and a small-diameter journal outer shaft portion 10e of the large diameter of the oil chamber 60 The lubricating oil can pass straight through the oil groove 59 without opposing the centrifugal force, and the crankpin 10p
Refueling can be performed smoothly.

[0050] By the way, the ball bearing 15 ₁ outside of the oil chamber 60, the oil reservoir of the crank web 10w outside 61
To pass communication between the oil grooves 59 formed on the outer peripheral surface of the left crank journal 10j ₁ can be easily processed it. Particularly, in the case of arranging the oil groove 59 parallel to the axis of the left crank journal 10j _1, since this can be simultaneously formed during the forging of the crank shaft 10, so eliminating the need for special grooving step, The productivity of the crankshaft 10 can be increased, and the cost can be reduced.

[0051] Also, oil grooves 59 of the left crank journal 10j ₁ outer circumference, since the crank pin 10p with respect to the rotational center of the left crank journals 10j ₁ are positioned at locations phase-shifted substantially 90 °, the piston 11 When reaching the top dead center and the bottom dead center, the oil groove 59 is inserted into the cylinder bore 7a.
Will be located on a plane perpendicular to the axis, thus, to avoid to join large becomes vertical load from the piston 11 in the vicinity of the oil groove 59 of the left crank journals 10j _1, left Clan journal by the oil groove 59 it is possible to prevent the reduction in strength of 10j _1.

The present invention is not limited to the above embodiment, and various design changes can be made without departing from the gist of the present invention. For example, it is also possible instead of the ball bearing 15 ₁ for supporting the crank journal 10j _1, provided a plain bearing. The oil groove 59 and the oil reservoir 61 can be provided on the right side of the crank journal 10j ₂ and crank webs 10w.

[0053]

As described above, according to the first aspect of the present invention, a side plate that defines an oil reservoir communicating with an outer peripheral surface of a crank pin is attached to an outer end surface of a crank web.
In a crankshaft oil supply passage structure in which a supply oil passage communicating with an oil pump communicates with the oil reservoir, the oil supply is provided via an oil groove formed on an outer peripheral surface of a crank journal supported on a crankcase via a bearing. Since the oil passage and the oil sump are communicated with each other, it is easy to form the oil groove on the outer peripheral surface of the crank journal. Therefore, the communication between the supply oil passage and the oil sump can be easily performed, and the production of the crankshaft can be easily performed. Performance can be enhanced and costs can be reduced.

According to the second feature of the present invention, since the oil groove is formed in parallel with the axis of the crank journal, the oil groove can be formed simultaneously with forging of the crankshaft. This eliminates the need for a simple groove machining step, thereby further increasing the productivity of the crankshaft.

Further, according to the third feature of the present invention, the oil groove is arranged at a position which is out of phase with the crank pin by about 90 ° with respect to the rotation center of the crank journal.
It is possible to prevent a large vertical load from being applied from the piston near the oil groove of the crank journal, and to prevent a decrease in the strength of the crank journal due to the oil groove.

Further, according to the fourth feature of the present invention, the crank journal is formed to have a larger diameter than the journal outer shaft extending outwardly therefrom. An annular oil chamber is formed in the annular stepped portion, and the crankcase supporting the bearing defines an annular oil chamber facing the outer surface of the bearing and the inlet of the oil groove. Because the oil passage is connected, the bearing that supports the crank journal can be lubricated by the lubricating oil that has flowed into the annular oil chamber from the supply oil passage, and the lubricating oil in the annular oil chamber can be lubricated without opposing the centrifugal force. Can be passed straight through,
Oil can be smoothly supplied to the crankpin.

[Brief description of the drawings]

FIG. 1 is a rear side view of a motorcycle to which the present invention is applied.

FIG. 2 is a sectional view taken along line 2-2 of FIG. 1;

FIG. 3 is a sectional view taken along line 3-3 in FIG. 2;

FIG. 4 is a sectional view taken along line 4-4 in FIG. 3;

FIG. 5 is a sectional view taken along line 5-5 of FIG. 3;

FIG. 6 is a sectional view taken along line 6-6 of FIG. 3;

FIG. 7 is an enlarged view around the oil pump of FIG. 3;

FIG. 8 is a sectional view taken along line 8-8 in FIG. 7;

FIG. 9 is an exploded perspective view of a crankshaft.

FIG. 10 is a perspective view of a lid.

[Explanation of symbols]

6 ... Crank case 10 ... Crank shaft 10e ... Journal outer shaft 10j ₁ ... Crank journal 10p ... Crank pin 10w ... Crank web 15 ₁ ···· Bearing (ball bearing) 32 ··· Oil pump 58 ··· Supply oil passage 59 ···· Oil groove 60 ···· Oil chamber 61 ···· Oil pool 67 ····· Step 71 ··· Side plate

Claims (4)

[Claims] 1. An outer end surface of a crank web (10w)
A side plate (71) defining an oil sump (61) communicating with the outer peripheral surface of the crank pin (10p) is attached, and a supply oil passage (58) communicating with an oil pump (32) is connected to the oil sump (61). In the crankshaft oil supply path structure which is communicated with the crankshaft (6), the crank journal (10j ₁ ) is supported on the outer peripheral surface of the crank journal (10j ₁ ) via a bearing (15 ₁ ) through an oil groove (59). An oil supply passage structure for a crankshaft, characterized in that the oil supply passage (58) and the oil sump (61) communicate with each other. 2. A crankshaft oil supply passage according to claim 1, wherein said oil groove (59) is formed in parallel with an axis of a crank journal (10j ₁ ). Construction. 3. The crankshaft oil supply passage structure according to claim 2, wherein the phase of the oil groove (59) is shifted from the crank crank pin (10p) by about 90 ° with respect to the rotation center of the crank journal (10j ₁ ). The crankshaft oil supply passage structure, which is located at a position. 4. The crankshaft oil supply passage structure according to claim 1, wherein the crank journal (10j ₁ ) has a larger diameter than a journal outer shaft portion (10e) extending outwardly. The crank journal (10j ₁ ) and the journal outer shaft (10j ₁ )
e) annular step between (67), the inlet was opened in the oil groove (59), the crank case (6) for supporting the bearing (15 _1), said bearing (15 ₁₎
Annular oil chamber (6) facing the outside surface of the oil groove and the inlet of the oil groove (59).
0), and the oil supply passage (5) is provided in the oil chamber (60).
8) A crankshaft lubrication passage structure, characterized in that: