CN1139732C - Crankshaft Oil Supply Circuit Structure - Google Patents

Abstract

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. 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

Crankshaft Oil Supply Circuit Structure

The invention mainly relates to an oil supply passage structure for lubricating the outer peripheral surface of a crankpin of an engine crankshaft. In particular, on the outer end surface of the web of the crankshaft, a side plate defining an oil storage portion communicating with the outer peripheral surface of the crankpin, and a crankshaft oil supply passage connecting the oil supply passage connected to the oil pump with the oil storage portion are mounted. Structural improvements.

As for the oil supply passage structure of the crankshaft, the structure disclosed in the Japanese Publication No. 57-45460 etc. is a known technology.

In the oil supply passage structure described in the above publication, since the oil supply passage connected to the oil pump communicates with the above-mentioned oil storage part, a curved oil hole from the shaft end of the crankshaft to the above-mentioned oil storage part should be processed on the crankshaft.

However, when processing such a curved oil hole, since it is necessary to use a drill to process in two directions, the time required for processing is relatively long, which is one of the main reasons why the cost cannot be reduced.

The present invention was made in view of the above problems, and an object of the present invention is to provide an oil supply passage structure of a crankshaft which can communicate with the oil supply passage through a groove which is very easy to process, and which can reduce costs.

In order to accomplish the above object, the first aspect of the present invention is that a side plate is mounted on the outer end surface of the web of the crankshaft. The side plate divides and forms an oil storage part communicated with the outer peripheral surface of the crankpin, and the oil supply passage connected to the oil pump communicates with the above-mentioned oil storage part, and is formed by the outer peripheral surface of the crankshaft journal supported on the crankcase through a bearing. The oil tank communicates between the above-mentioned oil supply passage and the oil storage part.

According to the first aspect, the oil groove is easily machined on the outer peripheral surface of the crankshaft journal, and the communication between the oil supply passage and the oil storage portion can be easily realized, thereby improving the productivity of the crankshaft and reducing the cost.

In a second aspect of the present invention based on the first aspect, the oil groove is formed parallel to the axis of the crankshaft journal.

According to the second aspect, since the above-mentioned oil groove can be formed at the same time as the crankshaft is forged, there is no need for a special groove processing process, which improves the productivity of the crankshaft and reduces the cost.

In a third aspect of the present invention based on the second aspect, the oil groove is provided at a position shifted from a phase of the crankpin by approximately 90° with respect to a rotation center of the crankshaft journal.

According to the third aspect, when the piston moves back and forth between the top dead center and the bottom dead center, the oil groove is positioned on a plane perpendicular to the axis of the cylinder bore, and it is possible to avoid applying a large vertical load from the piston to the vicinity of the oil groove. , to prevent the reduction in the strength of the crankshaft journal caused by the oil groove.

According to a fourth aspect of the present invention based on the first to third aspects, the crankshaft journal is made to have a large diameter structure larger than the outer shaft portion of the journal extending outward from the journal, and the inlet of the oil groove is opened at the crankshaft journal. The annular step portion between the crankshaft journal and the outer shaft portion of the journal forms an annular oil chamber facing the outer surface of the bearing and the inlet of the oil groove by means of the crankcase supporting the bearing. An oil passage is connected to the oil chamber.

According to the fourth aspect, the lubricating oil flowing into the annular oil chamber from the oil supply passage can lubricate the bearing supporting the journal of the crankshaft, and the lubricating oil in the annular oil chamber can directly pass through the oil groove in a direction not against the centrifugal force, which can smoothly Supply oil to the crankpin.

Fig. 1 is a side view of the rear portion of a motorcycle suitable for use in the present invention.

Fig. 2 is a cross-sectional view of section 2-2 in Fig. 1 .

Fig. 3 is a cross-sectional view of section 3-3 in Fig. 2 .

Fig. 4 is a cross-sectional view of section 4-4 in Fig. 3 .

Fig. 5 is a cross-sectional view of section 5-5 in Fig. 3 .

Fig. 6 is a cross-sectional view of section 6-6 in Fig. 3 .

Fig. 7 is an enlarged view around the oil pump in Fig. 3 .

Fig. 8 is a cross-sectional view of section 8-8 in Fig. 7 .

Fig. 9 is an exploded perspective view of the crankshaft.

Fig. 10 is a perspective view of the cover.

Hereinafter, an embodiment of the present invention will be described based on an embodiment of the present invention shown in the drawings.

First of all, in Fig. 1, the two-wheeled motor vehicle 1 is a small motorcycle. At the rear of the vehicle frame 2, a power unit P for driving the rear wheel Wr is installed in a freely swingable up and down direction through a connecting rod 9, and at the same time A rear shock absorber 3 is installed between the power unit P and the vehicle frame 2 .

As shown in FIG. 2 , the power unit P includes: a water-cooled four-stroke engine 4 and a belt-type continuously variable transmission 5 combined with the left side of the engine 4 . A rear wheel Wr located directly behind the engine 4 is attached to the rear end side of the continuously variable transmission 5 .

In FIGS. 2 to 4 , the engine 4 has a crankcase 6 , a substantially horizontal cylinder block 7 connected to the front of the crankcase 6 , and a cylinder head 8 connected to the cylinder block 7 as the main body of the engine. A crankshaft 10 housed and supported in a crankcase 6 is connected to a piston 11 that moves up and down in a cylinder bore 7 a of a cylinder block 7 through a connecting rod 12 .

A well-known operating valve mechanism 74, an air intake valve 72 and an exhaust valve 73 opened and closed by the operating valve mechanism 74 are arranged on the cylinder head 8. Camshaft 14 (see FIG. 4 ).

The crankcase 6 is composed of a front case half 6a integrally connected to the cylinder block 7 and a rear case half 6b joined to the front case half 6a by bolts. The left and right crank journals 10j ₁ and 10j ₂ of the crankshaft 10 are clamped between the case halves 6a and 6b by ball bearings 15 ₁ and 15 ₂ , respectively. The drive pulley 16 of the above-mentioned continuously variable transmission 5 is attached to a journal outer shaft portion 10e extending outward from the left crank journal 10j ₁ of the crankshaft 10 . The gearbox 17 is connected to the left end surface of the crankcase 6 by bolts.

At the right end portion of the crankcase 6 on the opposite side of the continuously variable transmission 5, a transmission chamber 18 in which the timing transmission device 13 is disposed and a cylindrical sub-chamber 19 adjacent to the outside of the transmission chamber 18 are formed. An oil seal 21 that is in sealing contact with the outer peripheral surface of the crankshaft 10 is attached to a partition wall 20 between the transmission chamber 18 and the sub-chamber 19 .

As shown in Figures 3 and 5, in the auxiliary machine room 19, several bosses 19a are protruded on its inner wall, and the stator 22s of the generator 22 is fixed on the several bosses with several bolts 23 (refer to Figure 5). On the platform 19a, the rotor 22r is fixed to the right end of the crankshaft 10 with bolts 24.

Further, a sub-chamber cover 25 and a fan cover 26 are sequentially connected to the right end of the crankcase 6 . At the outer end of the fan cover 26 is mounted a radiator 28 for the cooling periphery of the engine. A cooling fan 27 for cooling the radiator 28 and the generator 22 is arranged inside the fan cover 26 . The cooling fan 27 is fixed to the crankshaft 10 together with the rotor 22r by the aforementioned bolts 24 .

As shown in Figures 3 and 4, an oil storage portion 29 is formed at the bottom of the crankcase 6, and the lubricating oil 30 stored in the oil storage portion 29 is sucked by an oil pump 32 through an oil filter 31, and the oil pump 32 delivers the oil to the crankshaft 10 and other parts of the engine.

A cylindrical filter chamber 33 opened on the front side is formed at the lower portion of the front case half body 6a. The chamber 33 accommodates the cup-shaped oil filter 31 and a holding spring 35 that presses a seal member 34 provided at the opening end of the oil filter 31 toward the inner wall of the chamber 33 . A cover 36 is screwed to the opening of the chamber 33 .

The filter chamber 33 is divided by the oil filter 31 into a raw room corresponding to the inside of the oil filter 31 and a clean room on the outside. The raw room is connected to the inlet oil passage 37 connected to the oil storage part 29, and the clean room passes through the outlet oil passage. 38 communicates with the suction port 32i of the oil pump 32 .

And if cover 36 is unloaded, take out oil filter 31, can clean it, perhaps allow oil to pass through filter chamber 33 and the lubricating oil 30 of oil storage part 29 is discharged. Thus, the cover 36 also doubles as the drain bolt.

In FIG. 7 , an oil pump 32 is provided on the inner wall of the transmission chamber 18 on the opposite side of the partition wall 20 . The oil pump 32 is provided with a pump casing 40 , a pump rotor 41 accommodated in the pump casing 40 , and a pump cover 42 engaged with an opening surface of the pump casing 40 . The pump cover 42 is provided with the aforementioned suction port 32i and discharge port 32o. Further, the pump casing 40 and the pump cover 42 are fixed to the inner wall of the transmission chamber 18 by bolts 43 with the pump cover 42 as the inner side. A pump shaft 46 penetrating through the bearing hole 45 of the pump casing 40 is removably fitted and connected to the segment-shaped connection hole 44 of the pump rotor 41 .

The boss 48 a of the driven gear 48 is fitted on the pump shaft 46 and connected to the pump shaft 46 by a connecting pin 68 . That is, as shown in FIG. 8 , the connecting pin 68 is installed on the pump shaft 46 in a manner of crossing the pump shaft 46 , and cooperates with the keyway 69 on the end surface of the boss 48 a of the driven gear 48 , thereby connecting the pump shaft 46 and the pump shaft 46 . The driven gears 48 are connected together.

In the above-mentioned transmission chamber 18 , the driven gear 48 is decelerated and driven by the drive gear 47 fixed on the crankshaft 10 , and has a large diameter away from the oil pump 32 . In addition, the sprocket 49 of the above-mentioned timing transmission device 13 is integrally formed on the drive gear 47 .

On the above-mentioned partition wall 20, a small-diameter circular installation hole 50 having approximately the same diameter as the oil pump 32, that is, far away from the driven gear 48, is provided at the part facing the oil pump 32. The loading and unloading operations, especially the loading and unloading of the bolt 43 can be realized.

A cover body 52 is fitted into the attachment hole 50 via a seal member 53 . The outer end of the pump shaft 46 is rotatably supported on the inner surface of the cover body 52 , and a bag-shaped bearing hole 51 for restricting the movement of the pump shaft 46 in the axial direction is provided. In addition, as shown in FIG. 10 , the cover body 52 is integrally provided with a fan-shaped flange 54 protruding radially from the peripheral edge of the outer end and a strut 55 protruding from the outer surface. The flange 54 is in contact with the partition wall 20 on the sub-chamber 19 side, and pushes the inner surface of the stator 22s to the tip of the support 55 through the elastic cover 56, thereby holding the cover 52 at a fixed position in the mounting hole 50.

The discharge port 32o of the oil pump 32 passes through the oil supply passage 58 formed in the front case half body 6a, the oil chamber 60 facing the outer surface of the ball bearing ₁₅₁ supporting the left crank journal _10j1 , and the left crank journal 10j. The oil groove 59 formed on the outer peripheral surface of ₁ , the oil storage part 61 provided on the crankshaft web _10w integrally connected with the left crankshaft journal 10j1, the hollow part 62 of the crankpin 10p and the radius provided on the crankpin 10p The oil injection hole 63 in the direction communicates with the outer peripheral portion of the crankpin 10p. The outer peripheral surface of the crank pin 10p opening the oil injection hole 63 supports the large end portion 12b of the connecting rod 12 via a needle bearing 64 (see FIG. 4 ).

Next, the above-mentioned oil passage structure will be described in detail.

On the outer wall 65 of the continuously variable transmission 5 side of the crankcase 6, the outer ring of the ball bearing 151 for supporting the left crankshaft journal _10j1 is embedded, and at the same time, the outer ring of the ball bearing ₁₅₁ closely connected to the journal outer shaft part 10e is installed. The contacting oil seal 66 defines the annular oil chamber 60 facing the outer surface of the ball bearing ₁₅₁ through the outer wall 65 and the oil seal 66 .

The left crankshaft journal _10j1 is a larger diameter portion than the journal outer shaft portion _10e extending outward from the journal 10j1, and therefore, between the left crankshaft journal _10j1 and the journal outer shaft portion 10e, Between them, an annular stepped portion 67 facing the oil chamber 60 is formed. On the outer peripheral surface of the left crank journal 10j ₁ , a pair of oil grooves 59 extending from the annular step 67 to the root of the left crank journal 10j ₁ are formed.

Since the oil groove 59 is formed when the crankshaft ₁₀ is forged, it is easy to form. It can be seen from FIG. 6 and FIG. The two positions of ° are arranged parallel to the axis of the left crankshaft journal 10j ₁ .

Furthermore, in the crankshaft 10, a circular recess 70 is formed on the outer surface of the crank web 10w on the same side as the left crank journal _10j1 . In this recess 70, an annular side plate 71 surrounding the left crank journal _10j1 is pressed. Between the side plate 71 and the crankshaft web 10w, the annular flat oil storage portion 61 described above is defined. The outlet of the oil groove 59 is opened on the inner side of the oil storage portion 61 in the radial direction. The hollow portion 62 of the crank pin 10p is opened in the middle portion of the oil storage portion 61 .

As shown in FIG. 6, on the front case half body 6a, the cylinder block 7, and the cylinder head 8, a second oil supply passage 58' branched from the above-mentioned oil supply passage 58 is provided, and the second oil supply passage 58' passes through the second oil supply passage 58'. Oil is supplied to the operation valve mechanism 74 described above.

Next, the action of this embodiment will be described.

When installing the oil pump 32 and its driving system, first, in the front front box half 6a combined with the rear box half 6b, insert the oil pump 32 inside the transmission chamber 18, and install it through the auxiliary machine room 19. The holes 50 are inserted into the bolts 43 in the transmission chamber 18 to install the oil pump 32 at a given position on the inner wall of the transmission chamber 18 .

Next, a large-diameter driven gear 48 is inserted into the transmission chamber 18 of the front case half body 6 a so as to be adjacent to the oil pump 32 . Then, the pump shaft 46 with the connecting pin 68 is passed through the installation hole 50 from the side of the auxiliary machine chamber 19, and inserted into the boss 48a of the driven gear 48, the bearing hole 45 of the pump casing 40 and the hole of the pump rotor 41 in sequence. In the connection hole 44, at the same time, the connection pin 68 is fitted into the key groove 69 of the above-mentioned boss 48a.

Finally, in the mounting hole 50 of the partition wall 20, a cover body 52 is fitted, and a sealing member 53 is mounted on the outer periphery of the cover body 52. While fitting the outer end of the pump shaft 46 into the bearing hole 51, the The flange 54 is in contact with the outer surface of the partition wall 20 . In this state, the tip portion of the strut 55 of the cover body 52 is covered by the elastic cover 56 .

In this way, even if the installation hole 50 of the partition wall 20 is smaller than the diameter of the driven gear 48, when the oil pump 32 is installed on the inner wall of the narrow transmission chamber 18, the driven gear 48 can be easily connected to the pump shaft 46. superior. Furthermore, since the small-diameter mounting hole 50 is a small-diameter mounting hole smaller in diameter than the driven gear 48, the strength of the partition wall 20 is hardly lowered, which contributes to weight reduction.

Since the axial movement of the pump shaft 46 passing through the driven gear 48, the pump housing 40, and the pump rotor 41 is restricted by the bag-shaped bearing hole 51 of the cover body 52 fitted in the mounting hole 50, there is no Parts such as clips specially used to prevent the pump shaft 46 from being pulled out are required, and the structural elements are simplified.

Since the bearing hole 51 of the cover body 52 and the bearing hole 45 of the pump housing 40 support the pump shaft 46 from both sides of the driven gear 48 , the support is firm and the durability of the oil pump 32 is improved.

Afterwards, when assembling the whole engine, the inner end surface of the stator 22s of the generator 22 fixed on the inner wall of the auxiliary machine room 19 of the crankcase 6 is pressed against the tip of the pillar 55 of the cover body 52 by the elastic cover 56, thereby, through The cover body 52 holds the flange 54 at a predetermined position in contact with the outer surface of the partition wall 20, and therefore, special holding members such as bolts are not 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 enable the oil pump 32 to be driven.

During the operation of the engine 4, since the driving gear 47 rotating simultaneously with the crankshaft 10 can reduce the speed and drive the driven gear 48, the rotor 41 of the oil pump 32 can be driven at an appropriate speed. The oil pump 32 that operates in this way sucks the lubricating oil 30 in the oil storage part 29 through the oil filter 31, and sends it under pressure to the oil supply passage 58, the oil chamber 60, the oil groove 59, the hollow part 62 of the crank pin 10p, and the oil injection hole. 63, the ball bearing 15 ₁ supporting the left crank journal 10j ₁ is lubricated in the oil chamber 60, and the outer peripheral surface, the needle bearing 64 and the inner peripheral surface of the large end portion 12b of the connecting rod 12 are lubricated in the crankpin 10p.

At this time, since the inlet of the above-mentioned oil groove 59 is opened on the annular step portion 67 between the large-diameter left crankshaft journal _10j1 and the small-diameter journal outer shaft portion 10e, the lubricating oil in the oil chamber 60 does not flow backwards and forwards. Directly passing through the oil groove 59 in the direction of the centrifugal force, the oil can be smoothly supplied to the crank pin 10p.

Since the oil chamber 60 outside the ball bearing ₁₅₁ communicates with the oil storage portion 61 outside the crankshaft web 10w, the oil groove 59 formed on the outer peripheral surface of the left crankshaft journal _10j1 can be easily processed. In particular, when the oil groove 59 is arranged parallel to the axis of the left crankshaft journal _10j1 , the groove 59 can be formed at the same time as the crankshaft 10 is forged. Therefore, no special grooving process is required, and the productivity of the crankshaft 10 is improved. Reduced costs.

In addition, since the oil groove 59 on the outer peripheral surface of the left crank journal 10j ₁ is arranged at a position with a phase shift of about 90° relative to the rotation center of the left crank journal 10j ₁ and the phase of the crank pin 10p, when the piston 11 is at the top dead center and the bottom dead center, When moving back and forth between the points, the oil groove 59 is in a position on a plane perpendicular to the axis of the cylinder bore 7a. Therefore, it is possible to avoid applying a large vertical load from the piston 11 to the vicinity of the oil groove 59 of the left crank journal 10j ₁ , preventing The strength of the left crank journal 10j ₁ due to the oil groove 59 is reduced.

The present invention is not limited to the above-mentioned embodiments, and various changes can be made without departing from the gist of the present invention. For example, instead of a ball bearing 15 ₁ for supporting the crankshaft journal 10j ₁ , a plain bearing can also be provided. In addition, the oil groove 59 and the oil storage portion 61 may also be provided on the right crankshaft journal 10j ₂ and the crankshaft web 10w.

According to the crankshaft oil supply passage structure of the first aspect of the present invention described above, the side plate is attached to the outer end surface of the crankshaft web. The side plate divides and forms an oil storage part communicated with the outer peripheral surface of the crankpin, and the oil supply passage connected to the oil pump communicates with the above-mentioned oil storage part, and is formed by the outer peripheral surface of the crankshaft journal supported on the crankcase through a bearing. The oil tank communicates between the above-mentioned oil supply passage and the oil storage part. Therefore, it is easy to process the oil groove on the outer peripheral surface of the crankshaft journal, and the communication between the oil supply passage and the above-mentioned oil storage part can be realized simply, thereby improving the productivity of the crankshaft and reducing the cost.

According to the crankshaft oil supply passage structure of the second aspect of the present invention, the oil groove is formed parallel to the axis of the crankshaft journal. Therefore, the groove can be formed at the same time as the crankshaft is forged, no special groove processing process is required, the productivity of the crankshaft is improved, and the cost is reduced.

According to the crankshaft oil supply passage structure according to the third aspect of the present invention, the oil groove is provided at a position shifted from the phase of the crank pin by approximately 90° with respect to the rotation center of the crank journal. It is possible to prevent a large vertical load from being applied to the vicinity of the oil groove of the crankshaft journal from the piston, and to prevent the strength reduction of the crankshaft journal due to the oil groove.

According to the oil supply passage structure of the crankshaft according to the fourth aspect of the present invention, the crankshaft journal is formed to have a larger diameter than the outer shaft portion of the journal extending outward from the journal, and the inlet of the oil groove is opened at the crankshaft journal. The annular step portion between the bearing and the outer shaft portion of the journal forms an annular oil chamber facing the outer surface of the bearing and the inlet of the oil groove by means of the crankcase supporting the bearing. The oil supply passage and The oil chamber is connected. Therefore, the lubricating oil flowing into the annular oil chamber from the oil supply passage can lubricate the bearing supporting the crankshaft journal, and the lubricating oil in the annular oil chamber can directly pass through the oil groove in the direction not against the centrifugal force, and the oil can be smoothly supplied to the crankpin. .

Claims (4)

1, a kind of oil path structure of bent axle, side plate (71) is installed on the exterior edge face of bent axle web (10w), described side plate (71) is divided and is formed the trapped fuel portion (61) that is communicated with the outer circumferential face of crankpin (10p), the fuel feeding path (58) that is connected in oil pump (32) is communicated with described trapped fuel portion (61), it is characterized in that, by means of passing through bearing (15 ₁) be supported on the crankshaft journal (10j on the crankcase (6) ₁) outer circumferential face on formed oil groove (59), will be between described fuel feeding path (58) and the trapped fuel portion (61) be communicated with.

2, require the oil path structure of 1 described bent axle according to power, it is characterized in that, described oil groove (59) is to be parallel to crankshaft journal (10j ₁) the mode of axis form.

3, require the oil path structure of 2 described bent axles according to power, it is characterized in that, described oil groove (59) is arranged on respect to crankshaft journal (10j ₁) rotating center and with the phase shifting of crankpin (10p) 90 ° position slightly.

4, require the oil path structure of each described bent axle of 1～3 according to power, it is characterized in that crankshaft journal (10j ₁) make greater than from this axle journal (10j ₁) the big gauge structure of the axle journal foreign side axial region (10e) that extends to foreign side, the inlet of described oil groove (59) is opened on this crankshaft journal (10j ₁) and axle journal foreign side axial region (10e) between circular step portion (67), by means of supporting described bearing (15 ₁) crankcase (6) divide to form in the face of described bearing (15 ₁) outer side surface and the ring-type grease chamber (60) of the inlet of described oil groove (59), described fuel feeding path (58) is connected with this grease chamber (60).

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