CN104343495A - Ventilating structure of internal combustion engine - Google Patents

Abstract

The present invention provides a ventilating structure of an internal combustion engine. With the supply of the clutch shaft inserted through the insertion hole as a vent channel, The ventilating structure can reduce costs and prevent the entire internal combustion engine is increased. The ventilating structure includes: the clutch shaft (39) inserted through the insertion hole (60b), the inserting hole (60b) from the central portion (P) along the radial direction toward the peripheral edge portion (Q) in the clutch cover (7) covers the outer side wall (7v) perforations made on the structure of the internal combustion engine in the ventilation in the vicinity of the insertion hole (60b) of the central portion (P) formed to form the side opening inlet (60a) to the transmission chamber vent (2M); and from the peripheral edge portion (Q) of the insertion hole (60b), to cover an outer peripheral wall (7s) and crankcase (2) is perforated, to form the upper rear space (2) within the crankcase formed the breather chamber (61) of the vent passage (60c, 60d).

Description

The ventilation device of internal-combustion engine

Technical field

The present invention relates to the ventilation device of the blow-by gas process in internal-combustion engine.

Background technique

In the past, propose there is such ventilation device: the blow-by gas in crankcase be involved in the rotary current produced because of the rotation in the external rotor portion of the AC generator integrally rotated with bent axle, by means of centrifugal force, oil content is separated, utilize the venting channels being formed at crankcase cover that the blow-by gas remaining in central authorities is imported ventilation chamber (for example, referring to patent documentation 1).

Patent documentation 1: Japanese Unexamined Patent Publication 9-53436 publication

In the ventilation device disclosed in patent documentation 1, the crankcase cover (ACG cover) of the AC generator arranged in the end of bent axle from outer side covers is roughly configured to bowl-shape by the perisporium of sidewall opposed with AC generator vertically and the exterior circumferential that covers AC generator, on sidewall, be radially formed with venting channels from the part opposed with the end of bent axle.

When the special venting channels of blow-by gas process will be formed especially on the sidewall of crankcase cover, due to as the clutch release shaft clutch cap of crankcase cover also will being installed the action from external control clutch, therefore, if venting channels and clutch release shaft will be located on a crankcase cover, then structure becomes complicated and is not easy processing.

Therefore, be formed as making as patent documentation 1 venting channels be arranged at ACG cover side and make clutch release shaft stay the such structure in clutch cap side time, machine shaping goes out both sides respectively crankcase cover must be configured, cost can be caused to raise, and cause whole internal-combustion engine to increase.

Summary of the invention

The present invention completes in view of such problem points, its object is to the ventilation device that a kind of internal-combustion engine is provided, wherein, by the patchhole that runs through running through insertion for clutch release shaft is used as venting channels, can reduces costs and prevent whole internal-combustion engine from increasing.

In order to reach above-mentioned purpose, invention described in technological scheme 1 is a kind of ventilation device of internal-combustion engine, in crankcase 2, axle is supported with bent axle 10, and be accommodated with speed changer M, the ventilation chamber 61 of carrying out gas-liquid separation to blow-by gas is formed at the upper back space in described crankcase 2, in the end outstanding to the side of described crankcase 2 of the main shaft 12 of described speed changer M, be provided with speed change clutch 30, the described speed change clutch 30 arranged in the side of described crankcase 2 is covered by clutch cap 7, this clutch cap 7 is roughly formed as bowl-shape by cover outer side wall 7v and cover periphery wall 7s, on the cover outer side wall 7v of described clutch cap 7, run through to have from the central position P opposed with the axis of described main shaft 12 along radiation direction towards peripheral part Q and run through patchhole 60b, make the clutch release shaft 39 of described speed change clutch 30 Detaching and Lapping be inserted described in run through in patchhole 60b, the feature of the ventilation device of described internal-combustion engine is, near the described described central position P running through patchhole 60b, be formed with the ventilation introducing port 60a to speed changer room 2M side opening, from the described described peripheral part Q running through patchhole 60b, described cover periphery wall 7s and described crankcase 2 are bored a hole, form the venting channels 60c be communicated with described ventilation chamber 61, 60d.

The feature of the invention described in technological scheme 2 is, in the ventilation device of the internal-combustion engine described in technological scheme 1, described in run through patchhole 60b the position that overlaps with described ventilation chamber 61 when being in along described bent axle 10 end on observation of described peripheral part Q.

The feature of the invention described in technological scheme 3 is, in the ventilation device of the internal-combustion engine described in technological scheme 1 or technological scheme 2, described venting channels 60c, 60d are with described to run through patchhole 60b vertical at described peripheral part Q.

The feature of the invention described in technological scheme 4 is, in the ventilation device of the internal-combustion engine described in any one in technological scheme 1 to technological scheme 3, described in run through patchhole 60b described ventilation introducing port 60a be formed as opposed with the side of described speed change clutch 30.

The feature of the invention described in technological scheme 5 is, in the ventilation device of the internal-combustion engine described in any one in technological scheme 1 to technological scheme 4, described in run through patchhole 60b and formed towards described peripheral part Q from described central position P along oblique upper.

The ventilation device of the internal-combustion engine according to technological scheme 1, running through patchhole 60b's for what make the clutch release shaft 39 of speed change clutch 30 Detaching and Lapping run through insertion, near the central position P opposed with the axis of main shaft 12, be formed with the ventilation introducing port 60a to speed changer room 2M side opening, from the peripheral part Q running through patchhole 60b, perisporium and crankcase 2 are bored a hole, form the venting channels 60c be communicated with the ventilation chamber 61 in the upper back space in crankcase 2, 60d, therefore, when blow-by gas being involved in the rotary current produced because of the rotation of speed change clutch 30 and utilize centrifugal force to make oil content be separated, blow-by gas residual near central part is imported from ventilation introducing port 60a runs through patchhole 60b, and pass from the patchhole 60b that runs through becoming venting channels the venting channels 60c be communicated with, 60d is imported into ventilation chamber 61, gas-liquid separation is carried out further in ventilation chamber 61.

Ventilation introducing port 60a is near the central part of speed change clutch 30, eliminate oil content and the blow-by gas remained near central part is imported into this ventilation introducing port 60a, therefore, following situation can not be there is: the oil content in blow-by gas immerses ventilation introducing port 60a and blocks ventilation introducing port 60a.

The patchhole 60b that runs through of the clutch release shaft 39 that the cover outer side wall 7v of clutch cap 7 is formed is utilized as venting channels, therefore, without the need to forming venting channels especially, can reduce costs, and, avoiding clutch cap 7 expansion vertically caused because newly forming venting channels at the cover outer side wall 7v of clutch cap 7, can prevent whole internal-combustion engine from becoming large.

The ventilation device of the internal-combustion engine according to technological scheme 2, position overlapping with ventilation chamber 61 when the peripheral part Q running through patchhole 60b is in the end on observation along bent axle 10, therefore, venting channels 60c, 60d is formed point-blank vertically to ventilation chamber 61 from the peripheral part Q running through patchhole 60b, venting channels 60c, 60d can be shortened, and easily carry out running through of venting channels 60c, 60d arranging processing.

The ventilation device of the internal-combustion engine according to technological scheme 3, venting channels 60c, 60d, with to run through patchhole 60b vertical at peripheral part Q, therefore, easily carry out running through running through of patchhole 60b arranging processing together with venting channels 60c, 60d.

The ventilation device of the internal-combustion engine according to technological scheme 4, the ventilation introducing port 60a running through patchhole 60b is formed as opposed with the side of speed change clutch 30, therefore, oil mostly disperses to the peripheral of speed change clutch 30 because of the rotation of speed change clutch 30, disperse from the side of speed change clutch 30 to side hardly, it is lower that oil immerses from the ventilation introducing port 60a opposed with the side of speed change clutch 30 possibility running through patchhole 60b.

The ventilation device of the internal-combustion engine according to technological scheme 5, the described patchhole 60b that runs through is formed from described central position P along oblique upper towards described peripheral part Q, therefore, in ventilation chamber 61, can venting channels 60c, 60d be passed through by the oil content after gas-liquid separation, flow down and be expelled in the 2M of speed changer room from ventilation introducing port 60a running through in patchhole 60b.

Accompanying drawing explanation

Fig. 1 is the two-wheeled unitary side view that an embodiment of the invention relate to.

Fig. 2 is the right side view of internal-combustion engine.

Fig. 3 is the rear view of internal-combustion engine.

Fig. 4 is the sectional view along the IV-IV line in Fig. 2.

Fig. 5 is the sectional view along the V-V line in Fig. 2.

Fig. 6 is the internal view of right crankcase cover.

Fig. 7 is the right side view of the internal-combustion engine observing right crankcase from outside.

Fig. 8 is the left side view of the internal-combustion engine observing right crankcase from inner side.

Fig. 9 is the right side view of the internal-combustion engine observing left crankcase from inner side.

Label declaration

1: internal-combustion engine; 2: crankcase; 2L: left crankcase; 2R: right crankcase; 2C: crank chamber; 2M: speed changer room; 3: cylinder block; 4: cylinder head; 5: valve mechanism cover; 6: left crankcase cover; 7: right crankcase cover (clutch cap); 7a: cylindrical part; 7b: inboard bearing boss part; 7c: outboard bearing boss part; 7d: barrel; 7e: spacing wall; 7f: cylindrical wall; 7s: cover periphery wall; 7v: cover outer side wall; 7g: fitting surface; 8: clutch chamber; 10: bent axle; 12: main shaft; 13: jack shaft; 15: trunnion shaft; 16: output sprocket; 23: main actuation gear; 24: active and passive gear; 29:AC generator; 30: speed change clutch; 31: outer clutch race; 32: inner clutch race; 35: pressing plate; 36: clutch spring; 37: trip(ping) lever; 39: clutch cam axle (clutch release shaft); 40: clutch operating bar; 41: clutch cable; 60a: ventilation introducing port; 60b: run through patchhole; 60c, 60d: venting channels; 61: ventilation chamber; 62: ventilation delivery line.

Embodiment

Below, based on Fig. 1 to Fig. 9, an embodiment of the invention are described.

Fig. 1 is the unitary side view of the saddle type two-wheeled 90 being equipped with internal-combustion engine 1 of the present embodiment.

In the present embodiment, decide all around using the state of the direction of advance towards two-wheeled 90 as benchmark.

For this vehicle frame 92 of two-wheeled 90, left and right main car frame 92b, 92b is in a pair from bending and form sharply rake 92ba, 92ba to below after turning to standpipe 92a rearward to extend, and its underpart be that く word forwards bends until underpart.

In addition, when side-looking is observed, under pairing left and right, vehicle frame 92c, 92c are from turning to standpipe 92a with the wide-angle tilted downward and extend substantially in parallel with the sharply rake 92ba of main car frame 92b.

Seat rail 92d, 92d rearward extend from the top of sharply rake 92ba, 92ba of main car frame 92b, 92b, and backstay 92e, 92e that the bottom of the central part of this seat rail 92d, 92d and sharply rake 92ba, 92ba links together is carry seat rail 92d, 92d.

In vehicle frame 92 so above, front fork 93 is pivotally supported on and turns in standpipe 92a, front-wheel 94 is supported on the lower end of front fork 93 by axle, steering handle 100 is arranged at the upper end of the pivot of front fork 93, front end is rearward extended by the back vent 95 that axle is supported on pivot plate 92f, described pivot plate 92f is located at the bottom of main car frame 92b, 92b, and trailing wheel 96 is supported on the rear end of back vent 95 by axle, and rear shock absorber 97 is installed between the central part of back vent 95 and backstay 92e, 92e.

Be provided with fuel tank 98 main car frame 92b, 92b are added, seat 99 is arranged on the rear of fuel tank 98 by seat rail 92d, 92d supporting.

The internal-combustion engine 1 be equipped on vehicle frame 92 is single cylinder 4 stroke IC engine of SOHC (Single Over Head Camshaft) type, its with following posture by suspension: make bent axle 20 relative to car body towards width of the carbody direction, and make cylinder lean forward a little and erect.

Front shroud 101 is covered with the top of lower vehicle frame 92c, 92c of vehicle frame 92 from the left and right sides, side cover 102 is covered with the left and right sides between internal-combustion engine 1 and seat 99, and back cover 103 is covered with the latter half part of seat rail 92d, 92d.

Front mudguard 104 is covered with the top of front-wheel 94, and rear mudguard 105 is covered with the top of trailing wheel 96.

Fig. 2 is the right side view of internal-combustion engine 1, and Fig. 3 is the rear view of internal-combustion engine 1, and Fig. 4 is the sectional view along the IV-IV line in Fig. 2, and Fig. 5 is the sectional view along the V-V line in Fig. 2.

With reference to Fig. 2, bent axle 10 axle towards left and right directions is being supported to the oblique upper of the crankcase 2 that can rotate freely, cylinder block 3 and cylinder head 4 are by overlapping successively and be fastened as a whole, cylinder head 4 is covered with valve mechanism cover 5, and cylinder block 3, cylinder head 4, valve mechanism cover 5 lean forward projecting from crankcase 2 slightly to front.

With reference to Fig. 4, in the cylinder block 3 of giving prominence to obliquely upward from crankcase 2, be embedded with piston 18 in the mode that can slide, piston 18 is connected with the crank pin 10p between crankweb 10w, 10w of being erected at bent axle 10 via connecting rod 19, and corresponding to the action of piston 18, driving crank 10 rotates.

Above piston 18, firing chamber 20 is formed with in the bottom of cylinder head 4.

The valve actuating gear (not shown) of inlet and exhaust valve is driven to be arranged at cylinder head 4, the opening of the porting of this this firing chamber 20 of inlet and exhaust valve opening and closing.

As shown in Figure 1, the suction tude 71 of rearward stretching out from cylinder head 4 links via throttle body 72 and air-strainer 73.

The outlet pipe 75 forwards stretched out from cylinder head 4 bends downwards, then rearward bends, and along the lower surface of crankcase 2 near rear and right side, and links with the silencing apparatus 76 on the right side being configured in trailing wheel 96.

With reference to Fig. 3 and Fig. 4, crankcase 2 is configured to be divided into left and right two halves, is formed with space in crankcase between left crankcase 2L and right crankcase 2R.

In crankcase, space is the vertical space formed by crankcase periphery wall 2Ls, 2Rs encirclement between bearing wall 2Lv, 2Rv in left and right opposite one another, each other to crankweb 10w the crank chamber 2C received and the speed changer room 2M received normal meshed gear transmission M of the counterweight forming bent axle 10 configures and is communicated with and forms a space in front and back.

Left crankcase cover 6 and right crankcase cover 7 cover the more lateral, left and right of this left crankcase 2L and right crankcase 2R, and AC generator 29 is incorporated in the Dynamo Room 9 in left crankcase cover 6, and speed change clutch 30 is incorporated in the clutch chamber 8 in right crankcase cover 7.

Clutch chamber 8 is communicated with speed changer room 2M.

The lateral part root of the crankweb 10w of bent axle 10 is supported on left and right opposite one another vertical bearing wall 2Lv, 2Rv of left crankcase 2L and right crankcase 2R by axle via metal bearing 11,11.

AC generator 29 is arranged at the left side of giving prominence to the left than the metal bearing 11 on the left of this of bent axle 10, and this AC generator 29 is covered by left crankcase cover 6.

With reference to Fig. 4, between the left and right sidewall that the main shaft 12 of normal meshed gear transmission M and jack shaft 13 are supported on vertical to the left and right bearing wall 2Lv, 2Rv of left and right crankcase 2L, 2R by axle rear via bearing 12b, 12b, 13b, 13b extends, the driving cluster gear 12g being supported in the main shaft 12 and passive tooth wheels 13g being supported in jack shaft 13 makes corresponding gear always intermesh and be accommodated in speed changer room 2M respectively.

Project on the right side in clutch chamber 8 in the running through right vertical bearing wall 2Rv to the right of main shaft 12, be provided with the speed change clutch 30 as many plates friction clutch.

Project in the running through left vertical bearing wall 2Lv to the left of jack shaft 13 on outside left part, be embedded with output sprocket 16.

Output sprocket 16 is wound with rear wheel drive chain 17.

Main shaft 12 is parallel relative to bent axle 10 with jack shaft 13, and with reference to Fig. 8, main shaft 12 is positioned at the top of retreading of bent axle 10, and jack shaft 13 is positioned at the more rear of main shaft 12 and the position of oblique a little below, and jack shaft 13 is positioned at than the position of bent axle 10 slightly by top.

Further, trunnion shaft 15 is arranged at the front of bent axle 10 parallel to each other.

With reference to Fig. 4, balancer driven gear 21, cam chain driving sprocket wheel 22, main actuation gear 23 with the mode rotated integratedly with bent axle 10 be entrenched in successively from left to right bent axle 10 the metal bearing 11 being supported on right vertical bearing wall 2Rv by axle and on right side outstanding to the right.

Balancer driven gear 21 engages with balance driven gear (not shown) and carries out transmission of power, and this balance driven gear is flush-mounted in the trunnion shaft 15 in the front of bent axle 10.

In order to valve actuating gear transmission of power extremely arranged on the top of cylinder head 4, cam chain driving sprocket wheel 22 is wound with cam chain 22c.

Main actuation gear 23 engages with active and passive gear 24 and carries out transmission of power, and this active and passive gear 24 is supported in the outer clutch race 31 (with reference to Fig. 4) of the speed change clutch 30 on the right side being located at described main shaft 12.

With reference to Fig. 4 and Fig. 5, outer clutch race 31 as the speed change clutch 30 of many plates friction clutch has been formed as round-ended cylinder body by bottom 31b and cylindrical part 31c, the circular hole running through the central authorities being arranged on bottom 31b is rotatably embedded in the cylinder base portion of active and passive gear 24, and be supported to centered by main shaft 12 rotatable, further, outer clutch race 31 circumferentially links with active and passive gear 24 via shock-absorbing spring 25.

The inner clutch race 32 arranged in the inner side of the cylindrical part 31c of outer clutch race 31 is embedded in main shaft 12 by spline, and rotates integratedly with main shaft 12.

The compression zone 32b of the bottom 31b of outer clutch race 31 faced by inner clutch race 32 has and the concentric cylindrical part 32c opposed with cylindrical part 31c, multiple friction disk 33 and clutch disk 34 are inserted in the annulus in the outside of the cylindrical part 32c of inner clutch race 32 by alternately chimeric in the inner side of the cylindrical part 31c of outer clutch race 31.

Friction disk 33 slides axially and is embedded in the cylindrical part 31c of outer clutch race 31 freely, and rotates integratedly with outer clutch race 31.

In addition, with friction disk 33 alternately the chimeric clutch disk 34 inserted slide axially and be embedded in the cylindrical part 32c of inner clutch race 32 freely, and to rotate integratedly with inner clutch race 32.

Pressing plate 35 is rotatably supported on the shaft on the lip part 37f of trip(ping) lever 37 via bearing 38, this trip(ping) lever 37 is inserted in the hollow portion that main shaft 12 is formed by chimeric sliding freely, pressing plate 35 presses outermost friction disk 33 by means of the elastic force of clutch spring 36 from outside, and the friction disk 33 of alternately chimeric insertion between the compression zone 32b of inner clutch race 32 and clutch disk 34 are extruded in the mode of clamping from both sides, speed change clutch 30 becomes fastening state due to the friction between friction disk 33 and clutch disk 34.

Trip(ping) lever 37 stretches out to the right than lip part 37f, the inside of the outstanding cylindrical part 7a formed on the internal surface that the tapered portion 37a formed at its terminal part is inserted in right crankcase cover 7.

And the cam 39a that rotate freely the inner end of that the earth's axis be supported on right crankcase cover 7, with clutch release shaft suitable clutch cam axle 39 vertical with trip(ping) lever 37 is sticked in the tapered portion 37a of the terminal part of this trip(ping) lever 37.

Clutch cam axle 39 makes outer end be projected into the outside of right crankcase cover 7, and the base end part of the clutch operating bar 40 vertical with clutch cam axle 39 is fitted the outer end (with reference to Fig. 5) being installed on clutch cam axle 39.

The terminal part of the end of clutch cable 41 and the swing of this clutch operating bar 40 combines.

Clutch cable 41 extends upward from the terminal part of clutch operating bar 40 along the cover periphery wall 7s of right crankcase cover 7, and be supported in the outstanding engaging portion of locking support 42 and forwards stretch out, this locking support 42 is installed in the top, rear of the ring-type frame wall 2Rss of right crankcase 2R.

Therefore, when clutch cable 41 is pulled due to the operation of driver, clutch operating bar 40 swings and clutch cam axle 39 is rotated, the cam 39a of clutch cam axle 39 makes trip(ping) lever 37 to axially right side is mobile, pressing plate 35 overcomes the elastic force of clutch spring 36 to axially right side is mobile together with trip(ping) lever 37, and thus, the pressing of friction disk 33 and clutch disk 34 is removed, form gap between, speed change clutch 30 becomes disengaged position.

And, with reference to the Fig. 1 as the right side view of car body, the lower lip 102e of the right side cover 102 of the central part of covering body extends from the position of the upper limb of the valve mechanism cover 5 along internal-combustion engine 1 of front side to below of retreading from the side, and along the back curve of crankcase 2, internal-combustion engine 1 main body of the oblique front lower place of right side cover 102 is almost all exposed, but, the clutch operating bar 40 projecting from the rear portion of crankcase 2 and from the clutch cable 41 that clutch operating bar 40 extends upward be in right side cover 102 lower lip 102e inner side (with reference to Fig. 2 double dot dash line shown in lower lip 102e), clutch operating bar 40 is by right side cover 102 protection.

With reference to Fig. 5 and Fig. 8, in the underlying space of main shaft 12 and jack shaft 13, be configured with shift drive mechanism 50.

In the below of main shaft 12 and the height and position roughly the same with bent axle 10, declutch shift shaft 51 is erected at the vertical bearing wall 2Lv in left and right of crankcase 2, between 2Rv, and then, in the below of declutch shift shaft 51, gearshift drum 52 is erected at the vertical bearing wall 2Lv in left and right of crankcase 2, between 2Rv, the reverse shift fork 53a of declutch shift shaft 51 is supported on by axle, 53b, 53c is moved vertically by the rotation of gearshift drum 52, select the driving cluster gear 12g of normal meshed gear transmission M and each meshed gears centering of passive tooth wheels 13g, effectively carry out the gear mesh of transmission of power, carry out speed change.

In the oblique rear lower side of gearshift drum 52, gearshift main shaft 54 runs through left vertical bearing wall 2Lv from left-external side and is set up in right vertical bearing wall 2Rv, and the rotation of gearshift main shaft 54 makes gear switching mechanism 55 action, and gearshift drum 52 is rotated (Fig. 5 reference).

Fig. 8 is the left side view eliminating left crankcase 2L and observe the internal-combustion engine 1 of right crankcase 2R from inner side, and the fitting surface 2Rf (part with shown in grid hatching) coordinated with left crankcase 2L of right crankcase 2R illustrates with ring-type (a part of cylinder portion is cut off).

Fig. 9 is the right side view eliminating right crankcase 2R and observe the internal-combustion engine 1 of left crankcase 2L from inner side, and the fitting surface 2Lf (part with shown in grid hatching) coordinated with right crankcase 2R of left crankcase 2L illustrates with ring-type (a part of cylinder portion is cut off).

Crankcase periphery wall 2Ls, 2Rs of the crank chamber 2C and speed changer room 2M that form left and right crankcase 2L, 2R together with left and right vertical bearing wall 2Lv, 2Rv cover periphery in the following manner: from the front of trunnion shaft 15 around to the below of bent axle 10 and normal meshed gear transmission M below and towards rear, at the rear of normal meshed gear transmission M around upward, and then arrive the top (with reference to Fig. 8, Fig. 9) of normal meshed gear transmission M.

Crankcase periphery wall 2Ls, 2Rs inner side end is each other fitting surface 2Lf, 2Rf.

The superior posterior of the speed changer room 2M in left and right crankcase 2L, 2R, ventilation chamber 61 bloats upward and is separated from speed changer room 2M by spacing wall 2Lt, 2Rt, and crosses over left and right crankcase 2L, 2R and formed.(with reference to Fig. 5, Fig. 8, Fig. 9).

Ventilation chamber 61 is formed as maze-type structure, gas-liquid separation is carried out to blow-by gas, the blow-by gas having isolated oil content is exported to outside by from ventilation delivery line 62 (with reference to Fig. 9), and this ventilation delivery line 62 embeds the ventilation chamber 61 of left crankcase 2L side from top.

Fig. 7 is the right side view of the state after being unloaded by right crankcase cover 7 of above-mentioned internal-combustion engine 1, and outstanding its right end face, the right side fitting surface 2Rg (part with shown in grid hatching) of ring-type that namely coordinates with right crankcase cover 7 being formed at the ring-type frame wall 2Rss of right flank together with bearing wall 2Rv vertical with the right side has been shown in right crankcase 2R.

The spacing wall 2Rt of the formation ventilation chamber 61 of right crankcase 2R extends to right side fitting surface 2Rg and forms venting channels 60d (with reference to Fig. 5), and the opening of venting channels 60d is formed at the position by the top at the rear portion of the right side fitting surface 2Rg of ring-type.

The right crankcase cover 7 covering the right side of this right crankcase 2R is roughly formed as bowl-shape by cover outer side wall 7v and cover periphery wall 7s, the end face of cover periphery wall 7s, i.e. fitting surface 7g (with reference to Fig. 6) are docked each other with the right side fitting surface 2Rg of the ring-type frame wall 2Rss of right crankcase 2R, speed change clutch 30 is accommodated in inside and right crankcase cover 7 is fixedly installed in right crankcase 2R.

Figure 6 illustrates the internal view of the right crankcase cover 7 on the right side covering this right crankcase 2R.

At the core of the circular plate like portion opposed with speed change clutch 30 of the internal surface of the cover outer side wall 7v of right crankcase cover 7, be formed with the described cylindrical part 7a of the tapered portion 37a insertion for the terminal part of trip(ping) lever 37, and, along the cylindrical part 7a from center rearward and slightly to the radiation direction of rear surface thereof, stretch out and be provided with clutch cam axle 39.

With reference to Fig. 5 and Fig. 6, clutch cam axle 39 is rotatably supported on the shaft on the inboard bearing boss part 7b formed as one with the cylindrical part 7a of right crankcase the cover 7 and outboard bearing boss part 7c being formed at cover periphery wall 7s.

Clutch cam axle 39 is vertical with cylindrical part 7a and run through inboard bearing boss part 7b, and cam part 39a engages with the tapered portion 37a in the insertion cylindrical part 7a of trip(ping) lever 37.

In the end running through outboard bearing boss part 7c laterally of clutch cam axle 39, setting-in the base end part of clutch operating bar 40.

The inner side at the position of the formation outboard bearing boss part 7c in the cover periphery wall 7s of spacing wall 7e crankcase cover 7 to the right bloats, and be formed to fitting surface 7g from the internal surface of cover outer side wall 7v, speed changer room 2M separates by spacing wall 7e, and forms venting channels 60c along cover periphery wall 7s towards vehicle-width direction.

Clutch cam axle 39 runs through venting channels 60c.

When right crankcase cover 7 is installed in right crankcase 2R, the opening of the venting channels 60c that the fitting surface 7g of right crankcase cover 7 is formed is aimed at the opening of the venting channels 60d formed on the right side fitting surface 2Rg of right crankcase 2R, and venting channels 60c is communicated with venting channels 60d.

Between the spacing wall 7e near the inboard bearing boss part 7b and outboard bearing boss part 7c of the axle supporting clutch cam axle 39 of right crankcase cover 7, be formed with barrel 7d along cover outer side wall 7v, the inside of this barrel 7d become run through insertion for clutch cam axle 39 run through patchhole 60b.

Namely, run through patchhole 60b and run through setting along radiation direction towards peripheral part Q from the central position P opposed with the axis of main shaft 12, form the part contacted with the inboard bearing boss part 7b of central position P running through the barrel 7d of patchhole 60b to be cut off, and be formed with the ventilation introducing port 60a (with reference to Fig. 5, Fig. 6) running through patchhole 60b opening to the inside.

The peripheral part Q running through patchhole 60b arrives venting channels 60c and is generally perpendicularly communicated with venting channels 60c.

Run through patchhole 60b between the internal surface and clutch cam axle 39 of barrel 7d, there is interval and play a role as venting channels, therefore, the ventilation introducing port 60a of clutch chamber 8 opening near the central position P opposed with the axis of main shaft 12 of the cover outer side wall 7v of right crankcase cover 7 runs through patchhole 60b via what extend along radiation direction in outside the cover sidewall 7v and then via venting channels 60c, 60d of extending along vehicle-width direction in the ring-type frame wall 2Rss of outside the cover perisporium 7s and right crankcase 2R, is communicated with ventilation chamber 61.

With reference to Fig. 6, at the internal surface of the cover outer side wall 7v of right crankcase cover 7, be formed with cylindrical wall 7f at the peripheral of cylindrical part 7a in heart shaped is outstanding.

Cylindrical wall 7f has the diameter making ventilation introducing port 60a be positioned at inner side, and by the cutaway existing for the barrel 7d that extends from cylindrical part 7a along radiation direction.

In the ventilation device of this internal-combustion engine 1, running through patchhole 60b's for what make the clutch cam axle 39 of speed change clutch 30 Detaching and Lapping run through insertion, near the central position P opposed with the axis of main shaft 12, be formed with the ventilation introducing port 60a to clutch chamber 8 side (2M side, speed changer room) opening, make the ring-type frame wall 2Rss of cover periphery wall 7s and right crankcase 2R from the peripheral part Q running through patchhole 60b, via the venting channels 60c bored a hole along vehicle-width direction, 60d is communicated with the ventilation chamber 61 in the upper back space in crankcase 2, therefore, the blow-by gas flowed in clutch chamber 8 is involved in the rotary current produced because of the rotation of speed change clutch 30, and when utilizing centrifugal force that oil content is separated, blow-by gas residual near the central part of the inner side of cylindrical wall 7f is imported from ventilation introducing port 60a runs through patchhole 60b, and pass from the patchhole 60b that runs through becoming venting channels the venting channels 60c be communicated with, 60d is imported into ventilation chamber 61, gas-liquid separation is carried out further in ventilation chamber 61.

Ventilation introducing port 60a is near the central part of speed change clutch 30, eliminate oil content to a certain extent and the blow-by gas remained near central part is imported into this ventilation introducing port 60a, therefore, following situation can not be there is: the oil content of the minimizing in blow-by gas immerses ventilation introducing port 60a and blocks ventilation introducing port 60a.

In addition, the ventilation introducing port 60a running through patchhole 60b is formed as opposed with the side of speed change clutch 30, therefore, oil mostly disperses to the peripheral of speed change clutch 30 because of the rotation of speed change clutch 30, disperse from the side of speed change clutch 30 to side hardly, it is lower that oil immerses from the ventilation introducing port 60a opposed with the side of speed change clutch 30 possibility running through patchhole 60b.

In this ventilation device, what utilize the clutch cam axle (clutch release shaft) 39 formed on the sidewall of the right crankcase cover 7 as clutch cap runs through patchhole 60b as venting channels, therefore without the need to forming venting channels especially, can reduce costs, and, avoiding right crankcase cover (clutch cap) expansion vertically caused because newly forming venting channels at the cover outer side wall 7v of right crankcase cover 7, can prevent whole internal-combustion engine from becoming large.

As shown in Figure 5, position overlapping with ventilation chamber 61 when the peripheral part Q running through patchhole 60b is in the end on observation along bent axle 10, therefore, venting channels 60c, 60d is formed point-blank vertically to ventilation chamber 61 from the peripheral part Q running through patchhole 60b, venting channels 60c, 60d can be shortened, and easily carry out running through of venting channels 60c, 60d arranging processing.

In addition, as shown in Figure 5, venting channels 60c, 60d, with to run through patchhole 60b vertical at peripheral part Q, therefore, easily carry out running through running through of patchhole 60b arranging processing together with venting channels 60c, 60d.

Run through patchhole 60b to be formed from central position P along oblique upper towards peripheral part Q, therefore, in ventilation chamber 61, can venting channels 60c, 60d be passed through by the oil content after gas-liquid separation, flow down and be expelled in clutch chamber 8 and then speed changer room 2M from ventilation introducing port 60a running through in patchhole 60b.

And, gas-liquid separation is carried out and blow-by gas after eliminating oil content is derived by the ventilation delivery line 62 from top in ventilation chamber 61, and be directed to air-strainer 73 by the breathing pipe (not shown) be connected with ventilation delivery line 62, and be again attracted in the gas handling system of internal-combustion engine 1 for burning.

Claims (5)

1. a ventilation device for internal-combustion engine, in crankcase (2), axle is supported with bent axle (10), and is accommodated with speed changer (M),

The ventilation chamber (61) of carrying out gas-liquid separation to blow-by gas is formed at the upper back space in described crankcase (2),

In the end outstanding to the side of described crankcase (2) of the main shaft (12) of described speed changer (M), be provided with speed change clutch (30),

The described speed change clutch (30) arranged in the side of described crankcase (2) is covered by clutch cap (7), this clutch cap (7) is roughly formed as bowl-shape by cover outer side wall (7v) and cover periphery wall (7s)

On the cover outer side wall (7v) of described clutch cap (7), run through to have from the central position (P) opposed with the axis of described main shaft (12) along radiation direction towards peripheral part (Q) and run through patchhole (60b)

Make the clutch release shaft (39) of described speed change clutch (30) Detaching and Lapping be inserted described in run through in patchhole (60b),

The feature of the ventilation device of described internal-combustion engine is,

Near the described described central position (P) running through patchhole (60b), be formed with the ventilation introducing port (60a) to speed changer room (2M) side opening,

From the described described peripheral part (Q) running through patchhole (60b), described cover periphery wall (7s) and described crankcase (2) are bored a hole, form the venting channels (60c, 60d) be communicated with described ventilation chamber (61).

2. the ventilation device of internal-combustion engine according to claim 1, is characterized in that,

The position that the described described peripheral part (Q) running through patchhole (60b) overlaps with described ventilation chamber (61) when being in the end on observation along described bent axle (10).

3., according to the ventilation device of internal-combustion engine according to claim 1 or claim 2, it is characterized in that,

Described venting channels (60c, 60d) is with described to run through patchhole (60b) vertical at described peripheral part (Q).

4. the ventilation device of the internal-combustion engine according to any one in claim 1 to claim 3, is characterized in that,

Described described ventilation introducing port (60a) of running through patchhole (60b) is formed as opposed with the side of described speed change clutch (30).

5. the ventilation device of the internal-combustion engine according to any one in claim 1 to claim 4, is characterized in that,

The described patchhole (60b) that runs through is formed from described central position (P) along oblique upper towards described peripheral part (Q).