CN1190152A

CN1190152A - Engine for motorcycle with cylinder head cover

Info

Publication number: CN1190152A
Application number: CN97119298A
Authority: CN
Inventors: 渥美友康
Original assignee: Yamaha Motor Co Ltd
Current assignee: Yamaha Motor Co Ltd
Priority date: 1996-09-06
Filing date: 1997-09-06
Publication date: 1998-08-12
Anticipated expiration: 2017-09-06
Also published as: CN1121549C; JP3634926B2; JPH1082346A; TW360747B

Abstract

The invention provides an engine, which can fully ensure the thermal diffusivity of a cylinder head; the spark plug of the engine can be taken down easily; the cylinder head of the engine can be inspected and maintained easily. The engine 27 comprises a cylinder head 30 with a spark plug 39, a left cylinder head casing 75 and a right cylinder head casing 76 detachably arranged on the upper part of the cylinder head. The cylinder head casings comprise side walls 75a and 76a which cover the upper part of the cylinder head broadside; upper walls 75b and 76b connected with the upper ends of the side walls; front walls 75c and 76c connected with the side walls and the front ends of the upper walls. An opening 98 which is open towards the front, the upper side and the rear of the cylinder head is arranged between the cylinder head casings. The cylinder head casing on the side of the spark plug is provided with a jut 77 which extends downwards and is folded towards the side of the cylinder head. The jut is provided with a spark plug outlet 78 which can keep the jut away from the spark plug, and a plurality of cooling sheets 79.

Description

Engine for motorcycle with cylinder head cover

The present invention relates to be loaded into the motor on the two-wheeled motor vehicle, particularly the structure around its cylinder head.

In the two-wheeled motor vehicle, the form of motor is owing to be subjected to forming about commercial and be important factor.For this reason, motor is exposed outside the motorcycle, promptly in the two-wheeled motor vehicle of so-called exposed type, adopt the appearance design of emphasizing that motor exists.

But, recently, be variation corresponding to diversified needs and market, general motor is loaded on the multi-form car body, to scheme the different car type of exploitation.Specifically, for desired not only the having little air displacement but also can guarantee preferably the car type of posture by bus in market, be that the motor that air displacement is little is loaded on the long the sort of car body of wheelbase.

This occasion, motor for little air displacement, particularly in order around cylinder head, to form compact structure, this motor is loaded on the above-mentioned the sort of large-scale car body, between the fuel tank of cylinder head and car body, formed big gap, thereby in the coordination that has influenced aspect the outward appearance between car body and the motor.

Therefore, former two-wheeled motor vehicle is that the cylinder head cover that can obviously see motor is installed on cylinder head top.This cylinder head cover is main from the side, the front reaches the top top that covers cylinder head; Can see under the situation of motor that from the side the side of this cylinder head cover has the shape bigger than cylinder head.And, owing to there is cylinder head cover, make cylinder head form big outward appearance on every side, make the size of motor be suitable for being installed on the car body.

Yet, because the said cylinder housing overlay masking top that cylinder head, make this cylinder upper part of the cover thermal diffusivity variation.Therefore, particularly under the situation that summer high temperature wets more,, influenced the performance of motor because cylinder head is overheated.

And because the top of cylinder head covers by cylinder head cover, when the operational maintenance inspection work such as adjustment of carrying out for example inspection, replacing and the tappet of spark plug, cylinder head cover has become the thing that is in the way.For this reason, when carrying out maintenance inspection work, need take off cylinder head cover, therefore leave the further room for improvement in maintenance inspection operability aspect from cylinder head.

The purpose of this invention is to provide so automobile-used motor of a kind of two-wheel, even it is under above-mentioned the sort of situation, owing to around cylinder head, be provided with the obvious cylinder head cover that can see, also the thermal diffusivity of cylinder head be can fully guarantee, and the dismounting of spark plug and the maintenance inspection work around the cylinder head easily carried out.

For achieving the above object, the feature of the engine for motorcycle that claim 1 is put down in writing is, equipping along the overall width direction have cylinder head to the outstanding spark plug in side, can be outwards on the top of this cylinder head the pairing left and right cylinder head cover of installation with taking off.And the said cylinder housing has sidewall, the upper wall that links to each other with this sidewall upper on the top that covers the said cylinder lid from the side and the antetheca that links to each other with this sidewall and upper wall front end.Be formed with the opening portion that the place ahead, top and rear to above-mentioned cylinder head are opened wide between the described cylinder head cover, and on cylinder head cover, have the extension part that stretches out towards the below, this extension part of closing up to above-mentioned cylinder head side and have for avoiding spark plug export mouth and a plurality of cooling fin that above-mentioned spark plug is cut into corresponding to above-mentioned spark-plug location one side.

By this structure, covering between the cylinder head cover of the cylinder upper part of the cover left and right sides, owing to be formed with the opening portion that opens wide to cylinder head the place ahead, top and rear, the hot gas in the cylinder head can outwards be shed by opening portion.And, because ambient air can flow between cylinder head and the cylinder head cover by this opening portion, make the ventilated of cylinder head cover inboard improve, cylinder upper part of the cover hot gas is difficult to assemble.

In addition, be positioned at the cylinder head cover of a corresponding side,, increased the area of contact of cylinder head cover and ambient air, improved the thermal diffusivity of this cylinder head cover owing to be provided with the extension part that comprises cooling fin with spark plug.And, in this case, because cylinder head cover is installed on the cylinder head, be delivered to heat on the cylinder head cover from this cylinder head, outwards shed by cooling fin, make original outward appearance preferably cylinder head cover can be used as the sink of cylinder head and applied in a flexible way.

Moreover, in above-mentioned structure,, when carrying out the spark plug dismounting, needn't take off cylinder head cover owing to the export mouth of spark plug by the cylinder head cover of a side exposes to the outside.And, only take off the cylinder head cover of this side, unlimited very big from spark plug to this scope of cylinder upper part of the cover to the motor side, make and carry out the maintenance on every side of cylinder head top and spark plug easily.

According to claim 2, it is characterized in that having vent on the antetheca of the cylinder head cover that aforesaid right requirement 1 is put down in writing.

Adopt this structure, when two-wheeled motor vehicle travels, cross the inboard that vent flows into cylinder head cover from the air communication of travelling in the place ahead, this air communication of travelling is crossed the rear that opening portion between the cylinder head cover of the left and right sides is discharged to cylinder head.Therefore, can guarantee the ventilated in space between cylinder head cover and the cylinder head fully, the hot gas that is trapped in this place is discharged to the outside.

According to claim 3, it is characterized in that to see under the situation of said cylinder from the side that aforesaid right requires the sidewall of 1 cylinder head cover of being put down in writing to have than the also big shape of this cylinder upper part of the cover side view.

Adopt this structure, can see under the situation of motor from the side, around the top of cylinder head, can obtain big outward appearance.Therefore, can emphasize the appearance design of the existence of motor.

According to claim 4, it is characterized in that cylinder head that aforesaid right requirement 3 is put down in writing has along the circumferencial direction of its outer circumferential face cylinder axle extends, and a plurality of cooling fins in the spaced apart and outstanding setting of above-mentioned cylinder axle direction, and, the antetheca of said cylinder housing and sidewall have the lower edge of the cooling fin almost parallel ground extension of the topmost part position of covering with said cylinder, the outer periphery portion adjacency of the cooling fin of the lower edge of this antetheca and sidewall and above-mentioned the topmost part position.

According to this structure,, can see cylinder head more significantly owing to there is cooling fin.And, because cylinder head cover is to dispose with the continuous mode of the cooling fin of the topmost part position of cylinder head, to have improved the one sense of this cylinder head cover and cylinder head.In addition, by on cylinder head cover, implementing chromium plating processing and grinding disposing, this cylinder head cover is obtained and the similarly exquisite processing of cylinder head, and cylinder head cover is adopted energetically as a key factor that influences the motor outward appearance, has further improved the outward appearance of motor.

Fig. 1 is the profile of the two-wheeled motor vehicle of embodiments of the invention;

The front elevation that Fig. 2 concerns for the position of the following pipe of cylinder head cover and the vehicle frame of expression motor and front fork;

Fig. 3 have for expression cylinder head cover motor one analyse and observe front elevation;

Fig. 4 is the sectional drawing of motor;

Fig. 5 is the planimetric map with motor of cylinder head cover;

Fig. 6 is the left surface figure with motor of cylinder head cover;

Fig. 7 is the right hand view with motor of cylinder head cover;

Fig. 8 is the sectional plain-view drawing of expression corresponding to the mounting structure of the cylinder head cover of cylinder head;

Fig. 9 is installed in cylinder head cover for expression the right hand view of the state on the cylinder head;

Figure 10 is the sectional view along the A-A line of Fig. 6;

Figure 11 is the sectional view along the B-B line of Fig. 7.

Below in conjunction with the description of drawings embodiments of the present invention.In the accompanying drawing:

Fig. 1 represents a kind of American two-wheeled motor vehicle.The vehicle frame 2 of this two-wheeled motor vehicle 1 has head pipe 3, the person in charge 4 who is connected as a single entity with this pipe 3 and the following pipe 5 that is connected as a single entity with head pipe 3.

Be responsible for 4 front half part 4a and manage from the beginning that 3 tilted rearward are downward extends linearlyly.The person in charge 4 latter half part 4b extends downwards from the rearward end of above-mentioned front half part 4a.

Under manage 5 and from the beginning manage 3 and extend downwards.This time pipe 5 and the latter half part 4b almost parallel ground configuration of being responsible for 4, this are time managed between the rearward end of 5 top and the person in charge 4 front half part 4a and are connected by trombone slide 6.In addition, be connected with pairing left and right back stay 7 (only showing a side among the figure) on the underpart of following pipe 5.

Back stay 7 has front half part 7a and latter half part 7b.The front half part 7a of back stay 7 rearward extends from managing 5 underpart down.The rearward end of the front half part 7a of back stay 7 interconnects by transverse arm 7c, is connected with the above-mentioned person in charge's 4 latter half part 4b on this transverse arm 7c.The latter half part 7b of back stay 7 protrudes upward from the rearward end tilted rearward of above-mentioned transverse arm 7c.

Be responsible for and be connected with pairing left and right seat guide rail 8 (only showing a side among the figure) on the rearward end of 4 front half part 4a.Seat guide rail 8 can see under the situation of vehicle frame 2 from the side from being responsible for the downward linearly extension of 4 tilted rearward, its be responsible for 4 front half part 4a on collinear position roughly.And the rearward end of this seat guide rail 8 is connected on the latter half part 7b of back stay 7.

As shown in Figures 1 and 2, head pipe 3 upper supports of vehicle frame 2 have front fork 10.Front fork 10 disposes pairing left and right breeches pipe 11a and 11b what the overall width direction was separated, has a pair of carriage 12a and 12b that described breeches pipe 11a is connected with the top of 11b, and this is supported on the head pipe 3 by not shown steering shaft carriage 12a and 12b.And, as shown in Figure 2, to watch from the place ahead under the situation of two-wheeled motor vehicle, following pipe 5 is arranged between above-mentioned breeches pipe 11a and the 11b, and the underpart upper support of this breeches pipe 11a and 11b has front-wheel 13.

As shown in Figure 1, the person in charge 4 front half part 4a upper support has fuel tank 15.The back of this fuel tank 15 disposes seat 16.Seat 16 is bearing in the top of the latter half part 7b of above-mentioned seat guide rail 8 and back stay 7.

The bottom of the latter half part 7b of back stay 7 is separately installed with a tail-bracket 18.Postbrachium 20 by rotating shaft 19 rotatably supports on this tail-bracket 18.Postbrachium 20 is to the rear extension of vehicle frame 2, and the rearward end upper support of this postbrachium 20 trailing wheel 21.

Rear stabilizer 22 is installed above the rearward end of postbrachium 20.Rear stabilizer 22 face forward on the rearward end of postbrachium 20 is tilted to extension.The front end of this rear stabilizer 22 is bearing on the first half of postbrachium 20 by supporting rod 23.And, can see under the situation of vehicle frame that from the side rear stabilizer 22 and seat guide rail 8 are on collinear position roughly.

And, be mounted with four-stroke air cooling single-cylinder engine 27 on the vehicle frame 2.This motor 27 is configured in by the person in charge 4 of vehicle frame 2, manage down 5 and the space that surrounds of the front half part 17a of back stay 7 in.Motor 27 has crankcase 28, from the upwardly extending cylinder block 29 of this crankcase and be connected in the cylinder head 30 of these cylinder block 29 upper ends.

Crankcase 28 is bearing in the front end of back stay 7 and is responsible on the underpart of 4 latter half part 4b.The inside of this crankcase 28 holds the bent axle (not shown) of extending along the overall width direction.

As shown in Figures 3 and 4, cylinder block 29 has a cylinder 29a, accommodates a piston 31 in this cylinder 29a.On the outer circumferential face of this cylinder block 29, be formed with a plurality of heat radiation cooling fins 32.Cooling fin 32 extends along the circumferencial direction of cylinder block 29, exists compartment of terrain, the configuration of almost parallel ground in the cylinder axle S of said cylinder body 29 direction simultaneously.

Cylinder head 30 has the cylinder head lid 35 that closes up to cylinder block 29, and the camshaft receiver portion 36 that projects upwards from this lid 35.Be formed with the recess 37 that constitutes the firing chamber, the spark plug fitting seat 38 that links to each other with this recess 37 on the lid 35.Spark plug fitting seat 38 is provided with prejudicially with respect to the cylinder axle S by the center, firing chamber, is exposed to the right side side of cylinder head 30 simultaneously.On this spark plug fitting seat 38, be inserted with spark plug 39.

Spark plug 39 tilts with respect to cylinder axle S, and outstanding to the right direction of cylinder head 30.On this spark plug 39, wear spark plug and emit 40, this spark plug emits 40 to have voltage ignition wire of high 40a.Spark plug emits the 40 right side sides that are arranged on the camshaft receiver portion 36 of cylinder head 30.

As shown in Figure 4, the lid 35 of cylinder head 30 has the intakeport 42 and the relief opening 43 that link to each other with recess 37.Described intakeport 42 and relief opening 43 clip cylinder axle S and dispose side by side at the fore-and-aft direction of cylinder head 30.

On the lid 35, supporting and making intakeport 42 Aspirating valves 44 that opens and closes and the outlet valve 45 that relief opening 43 is opened and closed.The inside of camshaft receiver portion 36 constitutes moving clack box 46.Should dispose a camshaft 47 and a pair of Rocker arm 4 8a and 48b in the moving clack box 46, wherein have air inlet cam 47a and exhaust cam 47b on the camshaft 47.

The valve drive end 50 that Rocker arm 4 8a, 48b are equipped with the cam tracker 49 that contacts with air inlet cam 47a and exhaust cam 47b respectively, close up to the tappet end 45a of the tappet end 44a of Aspirating valves 44 and outlet valve 45.On the valve drive end 50 of Rocker arm 4 8a, 48b, be screwed into adjustment screw rod 52 by lock-nut 51.This front end of adjusting screw rod 52 contacts with above-mentioned tappet end 44a, 45a respectively.

And, in this four stroke engine 27, between the front end of above-mentioned tappet end 44a, 45a and adjustment screw rod 52 predetermined tappet clearance is set.The adjustment operation of this tappet clearance is to be undertaken by lock-nut 51 being unscrewed, changed the inlet of adjusting screw rod 52.

As Fig. 4 and shown in Figure 5, on the camshaft receiver portion 36 of cylinder head 30, a pair of tappet that links to each other with moving clack box 46 is adjusted

hole

55a, 55b and is being opened wide.Tappet is adjusted

hole

55a, 55b and is closed up to the valve drive end 50 of Rocker arm 4 8a, 48b.Tappet is adjusted

hole

55a, 55b and is covered by removable tappet lid 56a, 56b.Described tappet lid 56a, 56b are arranged on the forward and backward position of camshaft receiver portion 36.

Therefore, the adjustment of tappet clearance operation is, with tappet cover 56a, 56b takes off, adjust

hole

55a, 55b by tappet and make the lock-nut 51 of Rocker arm 4 8a, 48b and adjust screw rod 52 and expose that the outside carries out.

As shown in Figure 3, at the left surface of camshaft receiver portion 36, be formed with the opening portion 57 that links to each other with moving clack box 46.Opening portion 57 is covered by removable camb cap 58.Camb cap 58 is shown in Figure 6 discoid, and the top of this camb cap 58 forms upwards outstanding a pair of supporting pieces 59a, 59b.Supporting pieces 59a, 59b also will project upwards than the top of camshaft receiver portion 36, and are separated from each other configuration at the fore-and-aft direction of this camshaft 36.

As Fig. 3 and shown in Figure 6, on the outer circumferential face of lid 35, a plurality of cooling fins 61 have been formed.Cooling fin 61 extends and has configuration with gap in the direction of above-mentioned cylinder axle S along the circumferencial direction of lid 35.And this cooling fin 61 is set to the position of above-mentioned spark plug fitting seat 38 correspondences.

On the left surface of camshaft receiver portion 36, a plurality of cooling fins 62 have been formed.Cooling fin 62 is parallel with the cooling fin 61 of lid 35, and has the compartment of terrain configuration in the direction of above-mentioned cylinder axle S.And roughly Shang Fang cooling fin 62 is longer along the length of the fore-and-aft direction of cylinder head 30, and longer towards the outstanding length in the side of this cylinder head 30.

Therefore, as shown in Figure 6, in the left side of motor 27, along with entering cylinder head 30 from cylinder block 29, the profile that contains the motor 27 of

cooling fin

32,61 and 62 increases successively.

In addition, because the cooling fin 62 of camshaft receiver portion 36 is set to the position corresponding to opening portion 57, the camb cap 58 that covers this opening portion has the cooling fin 63 that links to each other with cooling fin 62.

As shown in Figure 5, cylinder head 30 is connected on the cylinder block 29 by 4 cylinder bolt 64a-64d.The head 65 that cylinder bolt 64a-64d is configured in cylinder 29a location about, these cylinder bolts 64a-64d exposes on camshaft receiver portion 36.

And cylinder head 30 is suspended on the trombone slide 6 of above-mentioned vehicle frame 2.That is, shown in Fig. 5,6 and 8, be equipped with the base part 66 that suspension is used above the camshaft receiver portion 36.This base part 66 is positioned at the lower position of trombone slide 6, and a pair of suspension bracket 67a, 67b have been threaded on this trombone slide 6.Suspension bracket 67a, 67b extend downwards in parallel to each other from trombone slide 6, and between the underpart of described suspension bracket 67a, 67b, said base portion 66 couples together by suspension bolt 68.

As shown in Figure 4, the intakeport 42 of cylinder head 30 is to the back of lid 35 opening.Be connected with Carburetor 70 on the opening end of this intakeport 35.The relief opening 43 of cylinder head 30 is to the front openings of lid 35.Be connected with outlet pipe 71 on the opening end of this relief opening 43.Outlet pipe 71 is directed at the rear by the below of motor 27, and links to each other with baffler 72.

In addition, the two-wheeled motor vehicle 1 in the present embodiment, along with the requirement in market, its motor 27 is loaded on the vehicle frame 2 with large-size, can be clear that by Fig. 1, and it is big that the size of the wheelbase ratio engine 27 between front-wheel 13 and the trailing wheel 21 is also wanted.Shown in Fig. 1 and 2, first and second

cylinder head cover

75,76 that can obviously see motor 27 is installed on the cylinder head 30.

The cylinder head cover the 75, the 76th of Fig. 1 and Fig. 2 forms with aluminium alloy compression casting for example, and they are from the top of the camshaft receiver portion 36 of left and right side overlay masking said cylinder lid 30.

As Fig. 5 and shown in Figure 6, first cylinder head cover 75 of the leftward position of cylinder head 30 has all-in-one-piece sidewall 75a, upper wall 75b, antetheca 75c and rear wall 75d.Sidewall 75a covers the top of camshaft receiver portion 36 from left direction.Can see from left direction under the situation of cylinder head 30, sidewall 75a has the also big shape of side view than above-mentioned camshaft receiver portion 36 tops, and this sidewall 75a has the lower edge 75e that the cooling fin 62 with the topmost part position of camshaft receiver portion 36 extends abreast.The length of the fore-and-aft direction of this lower edge 75e forms longer than the cooling fin 62 of the topmost part position.

Upper wall 75b extends to the inboard of overall width direction from the upper end of sidewall 75a, covers above-mentioned camshaft receiver portion 36 from the top.Downward direction tilts upper wall 75b along with entering the rear.And this upper wall 75b has the otch 76f that is used to avoid the base part 66 that above-mentioned tappet lid 56a, 56b and cylinder bolt 64c, 64d and suspension use.

Antetheca 75c is connected in the front end of sidewall 75a, upper wall 75b, and covers the top of above-mentioned camshaft receiver portion 36 from the place ahead.This antetheca 75c has the lower edge 75g of the lower edge 75e that is connected in sidewall 75a as shown in Figure 3.The cooling fin 62 of the topmost part position of this lower edge 75g and camshaft receiver portion 36 extends in parallel.

Rear wall 75d is connected on the rear end of sidewall 75a and upper wall 75b.Rear wall 75d is positioned at the rear position on above-mentioned camshaft receiver portion 36 tops.This rear wall 75d rearward stretches out inclination along with entering the below.

And the lower edge 75g of the lower edge 75e of sidewall 75a and antetheca 75c is only in the outside of the outer periphery portion of the cooling fin 62 of the topmost part position of camshaft receiver portion 36, along this outer periphery portion configuration.Like this, improved of the one sense of first cylinder head cover 75 with cylinder head 30.

As Fig. 5 and shown in Figure 7, second cylinder head cover 76 of cylinder head 30 right positions has all-in-one-piece sidewall 76a, upper wall 76b, antetheca 76c and rear wall 76d.Sidewall 76a covers the top of camshaft receiver portion 36 from right direction.Can see from right direction under the situation of cylinder head 30 that sidewall 76a has the also big shape of side view than above-mentioned camshaft receiver portion 36 tops.This sidewall 76a has and is positioned at above-mentioned spark plug 39 and spark plug emits the lower edge 76e of 40 top positions.

Upper wall 76b extends to overall width direction inboard from the upper end of sidewall 76a, and covers above-mentioned camshaft receiver portion 36 from the top.This upper wall 76b also has for avoiding the otch 76f of base part 66 that above-mentioned tappet lid 56a, 56b and suspension use and suspension bolt 68.

Antetheca 76c is connected on the front end of sidewall 76a and upper wall 76b, and covers the top of above-mentioned camshaft receiver portion 36 from the place ahead.This antetheca 76c has the lower edge 76g on the lower edge 76e that is connected in sidewall 76a.

Rear wall 76d is connected on the rear end of sidewall 76a and upper wall 76b.This rear wall 76d is positioned at the rear position, top of above-mentioned camshaft receiver portion 36.

As shown in figure 11, on the lower edge 76e of the sidewall 76a of second cylinder head cover 76, be formed with, at the inboard diapire 76h that extends of overall width direction towards camshaft receiver portion 36.Be formed with the extension 77 of downward extension on the front end of this diapire 76h.Can be clear that by Fig. 3 and Fig. 7 extension 77 forms tabular that right flank to lid 35 and camshaft receiver portion 36 closes up, and the top of this extension 77 is around the place ahead and rear to camshaft receiver portion 36.

Extension 77 has for avoiding the spark plug export mouth 78 that spark plug 39 is cut in the position that closes up to above-mentioned spark plug 39.Spark plug export mouth 78 is connected on the above-mentioned spark plug fitting seat 38, and spark plug emits 40 outstanding through this spark plug export mouth 78.

On the outer circumferential face of extension 77, a plurality of cooling fins 79 have been formed.Cooling fin 79 is parallel with the cooling fin 32 of cylinder block 29, and has configuration with gap in the direction of above-mentioned cylinder axle S, and this cooling fin 79 is set to the position corresponding to spark plug export mouth 78.In addition, only Shang Fang cooling fin 79 is longer along the length of the fore-and-aft direction of cylinder head 30, and longer to the outstanding length in the side of this cylinder head 30.

Therefore, as shown in Figure 7, right side at motor 27, along with entering cylinder head 30 from cylinder block 29, the profile that contains the motor 27 of cooling

fin

32 and 79 becomes greatly successively, the lower edge 76e of the sidewall 76a of the outer periphery portion of the cooling fin 79 of the topmost part position and second cylinder head 76 and the lower edge 76g adjacency of antetheca 76c.And described

lower edge

76e, 76g are only in the outer periphery portion outside of the cooling fin 79 of the topmost part position, along this outer periphery portion configuration.

On the surface of sidewall 75a, the 76a of first and

second cylinder head

75,76,

upper wall

75b, 76b,

antetheca

75c, 76c and rear wall 75d, 76d, implement the polishing grinding disposing for obtaining good surface appearance.Therefore, sidewall 75a, 76a,

upper wall

75b, 76b,

antetheca

75c, 76c and rear wall 75d, 76d are processed to smooth surface respectively, and this first and second

cylinder head cover

75,76 is as the principal element of motor 27 outward appearances and adopted energetically.

As Fig. 8 and shown in Figure 10, first cylinder head cover 75 is supported on the above-mentioned camb cap 58.The sidewall 75a of first cylinder head cover 75 is positioned at the supporting pieces 59a of camb cap 38, the lateral location of 59b, and is formed with a pair of supporting recess 80a, 80b on this this sidewall 75a.Supporting recess 80a, 80b are configured in the corresponding position of above-mentioned supporting pieces 59a, 59b, and are separated from each other along the fore-and-aft direction of sidewall 75a.

On the end face of supporting recess 80a, 80b, the packing ring 81 that rubber is made is installed.The center portion of each packing ring 81 is by the bolt 83 of sleeve 82 insertion fixed covers.This bolt 83 is screwed in supporting pieces 59a, the 59b of camb cap 58 from the side of first cylinder head cover 75.

Therefore, when installing bolt 83, packing ring 81 is pressed on supporting pieces 59a, the 59b, make win cylinder head cover 75 by vibrationproof be bearing on supporting pieces 59a, the 59b.

Shown in Fig. 8,9 and 11, second cylinder head cover 76 is bearing on the camshaft receiver portion 36.On camshaft receiver portion 36, the carriage 85 that sheet metal is made is installed.First and

second support column

85b, 85c that carriage 85 has body 85a integratedly, links to each other with this body 85a.

Body 85a extends along fore-and-aft direction in the position that the sidewall 76a to second cylinder head cover 76 closes up.Be connected with a pair of nut 86 on this body 85a.Nut 86 is separated from each other configuration at the fore-and-aft direction of body 85a.

First and

second support column

85b, 85c extend to overall width direction inboard from front end and the rear end of body 85a.Be positioned at the top of cylinder bolt 64a of front end right side of the first support column 85b guide cam axle receiver portion 36 of body 85a front position.In this case, as shown in figure 11, the height dimension of the head 65 of cylinder bolt 64a forms greatlyyer than the head 65 of other cylinder bolt 64b-64d, and is superimposed with the first support column 85b on the head 65 of this cylinder bolt 64a.And, on the first support column 85b, inserting fixing bolt 87, this fixing bolt 87 is screwed on the head 65 of above-mentioned steel bolt 64a.Therefore, the first support column 85b is fixedly mounted on the cylinder bolt 64a.

Be positioned at the second support column 85c of the back-end location of body 85a, the top of the cylinder bolt 64b of the right side, rear end by camshaft receiver portion 36 and extending to above-mentioned suspension bolt 68.The front end of this second support column 85c, superimposed on the head 68a of suspension bolt 68.And, on the front end of the second support column 85c, being inserted with other fixing bolt 88, this fixing bolt 88 is screwed on the head 68a of suspension bolt 68.Therefore, the second support column 85c is fixedly mounted on the suspension bolt 68.

As shown in figure 11, the sidewall 76a of second cylinder head cover 76 closes up to the body 85a of carriage 85.Be formed with a pair of supporting recess 90a, 90b on the sidewall 76a.Described supporting recess 90a, 90b are configured in the corresponding position of above-mentioned nut 86, and are separated from each other at the fore-and-aft direction of sidewall 76a.

On the end face of supporting recess 90a, 90b the packing ring of being made by rubber 91 is installed.The center portion of each packing ring 91 is by the bolt 93 of sleeve 92 insertion fixed covers.This bolt 93 is screwed in the nut 86 of carriage 85 from the side of second cylinder head cover 76.

Therefore, when installing bolt 93, packing ring 91 is pressed on the body 85a of carriage 85, make second cylinder head cover 76 by vibrationproof be bearing on the carriage 85.

As shown in Figure 9, the body 85a of carriage 85 has supporting pieces 95a, the 95b that a pair of downward direction is extended.

Supporting pieces

95a, 95b dispose at the fore-and-aft direction of body 85a with being separated from each other.The underpart of supporting

pieces

95a, 95b closes up to the top of above-mentioned extension 77 inner face, and is separately installed with the damping piece of being made by rubber 96 on the underpart of this supporting pieces 95a, 95b.Damping piece 96 is contacted with the top inner face of extension 77, flexibly keeps this extension 77.

As Fig. 3 and shown in Figure 5, in the state that first and second

cylinder head cover

75,76 is installed on the cylinder head 30, described

cylinder head cover

75,76 disposes at the left and right directions of cylinder head 30 with being separated from each other.Therefore, between

cylinder head cover

75,76, formed the opening portion 98 that opens wide continuously along the place ahead, top and the rear of cylinder head 30.This opening portion 98 is connected respectively to the space between cylinder head 30 and first and second cylinder head cover 75,76.And the place ahead of this opening portion 98 is provided with the following pipe 5 that extends from above-mentioned head pipe 3 downwards.

Offer a plurality of vents 100,101 on antetheca 75c, the 76c of first and second cylinder head cover 75,76.Vent 100,101 forms the grooving shape of extending along the left and right directions of cylinder head 30, and disposes side by side in the short transverse of above-mentioned antetheca 75c, 76c.This vent 100,101 closes up to the upper front of camshaft receiver portion 36.Therefore, when two-wheeled motor vehicle travels, cross vent 100,101 from the air communication of travelling in the place ahead and flow in the space of

cylinder head cover

75,76 inboards.

As shown in Figure 1, contain above-mentioned head pipe 3 and reach the front end of the vehicle frame 2 of the joint of pipe 5 down, covered by fuel tank 15, and be positioned at the anterior position of this fuel tank 15 with the person in charge 4.The front end of this vehicle frame 2 covers by the vehicle frame lid of being made by synthetic resin 105.Pipe 5 downward directions are extended down, the cylinder head 30 towards motor 27 bends to circular-arc on one side at front end one edge of vehicle frame lid 105.

On the left and right side of vehicle frame lid 105, dispose a pair of trim 106a, 106b.Can see under the situation of two-wheeled motor vehicle 1 that from the side trim 106a, 106b extend along the fore-and-aft direction between first and second

cylinder head cover

75,76 of fuel tank 15 and motor 27, and the above-mentioned trombone slide 6 of overlay masking from the side.

Can be clear that by Fig. 2, trim 106a, 106b are above first and second

cylinder head cover

75,76 of motor 27, left and right side to vehicle frame lid 105 opens, and the front end of this trim 106a, 106b, and it is crooked to be circular-arc ground along the front end of above-mentioned vehicle frame lid 105.Be connected in this front end trim 106a, 106b below, work in coordination with the following of above-mentioned vehicle frame lid 105, when being formed in two-wheeled motor vehicle 1 and travelling, the guiding face that is used for making the air-flow that travels from the place ahead on first and second

cylinder head cover

75,76, to be guided, and the cylinder head 30 of guiding ratio engine 27 is wanted many air-flows that travels.

In addition, the upper limb of trim 106a, 106b and lower edge are bent to smooth wavyly, and its latter half part is connected on the fuel tank 15.And, couple together smoothly between trim 106a, 106b first and second

cylinder head cover

75,76, thereby kept the outward appearance of Japan's formula of two-wheeled motor vehicle 1 fuel tank 15 and motor 27.

By this structure, on the cylinder head 30 of motor 27, install to cover first and second

cylinder head cover

75,76 on described camshaft receiver portion 36 tops, thereby obtain the outward appearance bigger than cylinder head 30.In addition, also be not limited to motor 27 is loaded on the long vehicle frame of wheelbase, when obviously seeing motor 27, also can emphasize the existence of this motor 27, make vehicle frame 2 and motor harmonious aspect appearance.

In this case, first and second

cylinder head cover

75,76 left and right directions at cylinder head 30 are separated from each other, and between this

cylinder head cover

75,76, be formed with the place ahead at cylinder head 30, above and the opening portion 98 that opens wide continuously of rear.Therefore, in motor 27 runnings, the heat of cylinder head 30 is loose to the outside by above-mentioned opening portion 98.

And, in two-wheeled motor vehicle travels, cross the front end of opening portion 98 from the air communication of travelling in the place ahead, flow in the space between cylinder head 30 and first and second

cylinder head cover

75,76, this air-flow that travels from the rear end of opening portion 98 to the discharge of the rear of cylinder head 30.Therefore, in cylinder head 30, the ventilated of the part that is covered by first and second

cylinder head cover

75,76 is good, is difficult to be detained hot gas on cylinder head 30 tops.

Particularly in the present embodiment, owing on antetheca 75c, the 76c of first and second

cylinder head cover

75,76, be formed with vent 100,101 respectively, therefore be directly transferred to the front of camshaft receiver portion 36 from the air-flow that travels in the place ahead.Therefore, although the air-flow that travels of meeting to this opening portion 98 is subjected to down blocking of pipe 5, also can cool off the top of the cylinder head 30 that includes camshaft receiver portion 36 effectively, it is low that the thermal diffusivity of cylinder head 30 is unlikely to.

Owing to be positioned at second cylinder head cover 76 of spark plug 39 side positions, have the extension 77 that has cooling fin 79, increased the area of contact of this startup cylinder head cover 76 with ambient air, make the thermal diffusivity of second cylinder head cover 76 good.And in this case, for second cylinder head cover 76, the heat of cylinder head 30 is directly transmitted by bolt 93, perhaps transmits the radiation heat of this cylinder head 30, and the heat of this cylinder head 30 is dissipated energetically by cooling fin 79.The result, by being used to improve second cylinder head cover of seeing outside the motor 27 76 originally, sink as cylinder head 30 is applied in a flexible way, particularly owing to existing spark plug 39 to reduce under the situation of cooling fin 62, also improved the thermal diffusivity of the right side of the relatively poor cylinder head 30 of thermal diffusivity.

And, because having for avoiding spark plug 39, above-mentioned extension 77 emits 40 spark plug export mouth 78 with spark plug, spark plug 39 is being taken off from spark plug fitting seat 38, when perhaps being installed on the spark plug fitting seat 38, needn't take off second cylinder head cover 76 from cylinder head 30.

Moreover, unclamp bolt 93 with second cylinder head cover 76 when cylinder head 30 takes off, open wide to the right flank of motor 27 from the scope to the expansion of camshaft receiver portion 36 around the spark plug 39, thereby can carry out the operation of taking off of tappet lid 56a, 56b.In addition, the lock-nut 51 of Rocker arm 4 8a, 48b and adjustment screw rod 52 are exposed easily, thereby carry out the adjustment operation of tappet clearance easily.

And, support the carriage 85 of second cylinder head cover 76, because on the head 68a of the head that is connected to cylinder bolt 64a and suspension bolt 68, so needn't on camshaft receiver portion 36, form the special lug boss that blocks carriage 85.

In addition, when all being fastened on the support column 85b of carriage 85 on the camshaft receiver portion 36 by cylinder bolt 64a, the tightening torque of this cylinder bolt 64a is subjected to the influence of the planeness of the support column 85b that made by sheet metal easily, has the anxiety that error takes place between the tightening torque of other three cylinder bolt 64b-64d.

Yet, adopt above-mentioned structure, because the support column 85b of carriage 85, moment of torsion with regulation, be fastened on the cylinder head 30 by the dedicated fixed bolt 87 on the head 65 that is fixed in cylinder bolt 64a, therefore can prevent the variation of the tightening torque of cylinder bolt 64a, make the tightening torque of four cylinder bolt 64a-64d even.

And in the above-described embodiments, though first and second cylinder head cover is formed by aluminium alloy compression casting, the present invention is not limited thereto, the parts that this cylinder head cover is made as sheet metal, and it is good implementing the chromium plating processing in its surface.

In addition, motor involved in the present invention is not limited to air cooled engine, and much less it also is applicable to water cooled engine.

Among the present invention of Xiang Ximiaoshuing, the hot gas of cylinder head can shed to the outside by the opening portion between the cylinder head cover in the above.And because by this opening portion, ambient air flows between cylinder head and the cylinder head cover, makes that the ventilated of cylinder head cover inboard is good, and cylinder upper part of the cover hot gas is difficult to assemble.

In addition, the cylinder head cover owing at spark plug side position place has the extension that comprises cooling fin, has therefore increased the area of contact of cylinder head cover and ambient air, has improved the thermal diffusivity of this cylinder head cover.And, loose to the outside by cooling fin from the heat that cylinder head is delivered on the cylinder head cover, make original cylinder head cover also apply flexibly sink into cylinder head as the raising outward appearance.

Have again, in when operation of taking off of carrying out spark plug, needn't take off cylinder head cover from cylinder head, and only need take off the cylinder head cover of this side, just the side to motor is opened wide with enlarging from spark plug to cylinder upper part of the cover scope, therefore carry out the adjustment operation on every side of cylinder head top and spark plug easily, make the maintenance of motor good.

Claims

1. motor that two-wheel is automobile-used, it has along the cylinder head of overall width direction to the outstanding spark plug in side; Can be installed on the pairing left and right cylinder head cover on the top of this cylinder head; It is characterized in that:

The said cylinder housing have the top that covers said cylinder lid from the side sidewall, be connected in the upper wall of this sidewall upper, the antetheca that links to each other with the front end of described sidewall and upper wall;

Between described cylinder head cover, form towards the place ahead, top and the rear of above-mentioned cylinder head and open wide the branch opening portion; And

On a cylinder head cover corresponding to above-mentioned spark plug side position, have to the side of above-mentioned cylinder head and close up the extension that the ground downward direction is extended, this extension has for avoiding spark plug export mouth and a plurality of cooling fin that above-mentioned spark plug is cut into.

2. the automobile-used motor of two-wheel as claimed in claim 1 is characterized in that:

On the antetheca of said cylinder housing, be formed with vent.

3. the automobile-used motor of two-wheel as claimed in claim 1 is characterized in that:

Under the situation that can see the said cylinder lid from the side, the sidewall of said cylinder housing has the shape also bigger than the side view of this cylinder head upper wall.

4. the automobile-used motor of two-wheel as claimed in claim 3 is characterized in that:

The circumferencial direction that the said cylinder lid has along its outer circumferential face along the cylinder axle extends, and there are the outstanding a plurality of cooling fins that are provided with in compartment of terrain in the direction at above-mentioned cylinder axle, and, the antetheca of said cylinder housing and sidewall have the lower edge of the cooling fin almost parallel ground extension of the topmost part position of covering with said cylinder, the outer periphery portion adjacency of the cooling fin of the lower edge of described antetheca and sidewall and above-mentioned the topmost part position.