CN1278036C

CN1278036C - Forced air-cooled type engine for motorcycle

Info

Publication number: CN1278036C
Application number: CN 03136472
Authority: CN
Inventors: 挂水贤一郎; 畑山淳志
Original assignee: Honda Motor Co Ltd
Current assignee: Honda Motor Co Ltd
Priority date: 2002-06-03
Filing date: 2003-05-23
Publication date: 2006-10-04
Anticipated expiration: 2023-05-23
Also published as: ES2287383T3; CN1467368A; TW200400316A; EP1369560A3; EP1369560B1; JP3908983B2; JP2004011437A; EP1369560A2; TW593875B

Abstract

In a forced air-cooled type engine for motorcycle in which an engine main body comprising as a part of component elements thereof a cylinder head having a cylinder axis set substantially horizontally and a spark plug mounted at least one of left and right side surfaces is vertically swingably supported to a vehicle body frame and the cylinder head is covered with a shroud for forming a communication passage for flow of air for forced air cooling between itself and the cylinder head; to increase the degree of freedom in laying out a high-tension cord and to enable enhancement of flexural durability of the high-tension cord. An ignition coil(126)disposed on the rear side of the cylinder head is supported by one of a left-right pair of rear frame members (29 and 30) possessed by the vehicle body frame(25), and an other end portion of the high-tension cord(123)having one end connected to the ignition coil(126)is bent back in a roughly U shape from the front side of a plug cap (121) connected to the spark plug to the rear side of the plug cap (121) and is connected to the plug cap (121).

Description

The two-wheeled forcedly air-cooled engine of using

Technical field

The present invention relates to a kind of two-wheeled forcedly air-cooled engine of using, the body of this motor can be bearing on the vehicle frame with fluctuating, its cylinder-bore axis approximate horizontal of this engine body also is installed in cylinder head at least one side, the left and right sides as the part of constituting component with spark plug, cylinder head at least in the above-mentioned engine body is covered with guard shield, and this guard shield will be used to make the circulation flow path of the air ventilation that forced air cooling uses to be formed between itself and the above-mentioned cylinder head.

Background technique

Past, disclosed two-wheeled in by Japanese kokai publication hei 9-144520 communique with in the forcedly air-cooled engine, limit spark plug cap, spark plug cap is located on the guard shield towards the wall portion in the outside of car body.

But, above-mentioned existing two-wheeled with in the forcedly air-cooled engine, when the interval between the framework in the outside that is configured in the spark cap in spark plug cap and the vehicle frame is narrow, the drawing of the high-tension busbar (high tension cord) that is connected with spark plug cap towards the car body outside becomes difficult, the high-tension busbar bending is configured, is difficult to improve the crooked durability of high-tension busbar.

Summary of the invention

The present invention makes in light of this situation, its objective is the two-wheeled forcedly air-cooled engine of using that a kind of configuration degrees of freedom that has increased high-tension busbar is provided, can helps to improve the crooked durability of high-tension busbar.

In order to achieve the above object, the two-wheeled forcedly air-cooled engine of using of the present invention's first technological scheme, its engine body makes its cylinder-bore axis approximate horizontal, and spark plug is installed in cylinder head at least one side, the left and right sides as the part of constituting component, this engine body can be bearing on the vehicle frame with fluctuating, cylinder head at least in the above-mentioned engine body is covered with by guard shield, this guard shield will be used to make the circulation flow path of the air ventilation that forced air cooling uses to be formed between itself and the above-mentioned cylinder head, it is characterized in that, side's upper support of framework member spark coil after the pairing left and right that above-mentioned vehicle frame had, this spark coil is configured in the rear of above-mentioned cylinder head, is connected on this spark plug cap after rearward roughly turning back from the place ahead that is connected the spark plug cap on the above-mentioned spark plug in the other end that an end is connected the high-tension busbar on this spark coil U word shape.

According to such the present invention first technological scheme, be connected the high-tension busbar on the spark plug cap owing to extend to the place ahead from this spark plug cap, therefore, even the interval between the framework that is configured in the spark plug cap outside in spark plug cap and the vehicle frame is narrow, also can avoid interfering with vehicle frame, thereby can increase the degrees of freedom of configuration high-tension busbar, can set the bending radius of high-tension busbar significantly simultaneously, thereby can improve the durability of high-tension busbar.

Second technological scheme of the present invention, be on the basis of above-mentioned first technological scheme, it is characterized in that, a pair of top and lower cover parts up and down that above-mentioned guard shield mutually combines with having the above-mentioned cylinder head of common covering, the embedding hole that is used for chimeric above-mentioned spark plug is formed between the mating face of above-mentioned two cap assemblies, be provided with integratedly on the upper lid member from above cover the penthouse to the chimeric embedding part of above-mentioned embedding hole of above-mentioned spark plug cap, being applied the above-mentioned spark plug cap of bias voltage from the elastic force of above-mentioned high-tension busbar effect to the side around the axis of above-mentioned spark plug combines with spline positioning part butt on being formed on above-mentioned penthouse, and this spline positioning part is resisted above-mentioned elastic force and supported spark plug.According to such formation, spark plug cap since under the effect of the elastic force of high-tension busbar effect be formed on penthouse on the spline positioning part contact combination, therefore, in engine running, can prevent the rotational of spark plug cap around spark plug, can prevent the vibration of high-tension busbar thus, can prevent effectively that this high-tension busbar from contacting with other part.And, because the chimeric embedding part of spark plug cap and embedding hole is covered with by penthouse from the top, therefore, can make that fallen muddy water etc. are non-cohesive on the joint of high-tension busbar and spark plug cap with the member impacts of the top of engine body.

The 3rd technological scheme of the present invention is on the basis of above-mentioned second technological scheme, it is characterized in that, the retaining member of the high-tension busbar that maintenance links to each other with above-mentioned spark plug cap is installed on the retaining member fitting seat, this retaining member fitting seat and above-mentioned penthouse are formed on the above-mentioned upper lid parts continuously, according to such formation, by near spark plug cap, keeping high-tension busbar, can prevent the vibration of high-tension busbar more effectively, can increase the intensity of penthouse by the retaining member fitting seat.

Description of drawings

Fig. 1 is the side view of motor scooter type motor-driven cart.

Fig. 2 has omitted the vehicle body cover and has accommodated the two-wheeled intermediate portion stereogram of small-sized motor type under the case state.

Fig. 3 is the 3-3 amplification profile of Fig. 1.

Fig. 4 be Fig. 34 to diagrammatic sketch.

Fig. 5 be Fig. 35 to diagrammatic sketch.

Fig. 6 is the 6-6 sectional drawing of Fig. 3.

Fig. 7 is the figure that sees housing from cylinder head side.

Fig. 8 is the 8-8 sectional drawing of Fig. 7.

Fig. 9 is the 9-9 amplification profile of Fig. 6.

Figure 10 is the 10-10 sectional drawing of Fig. 9.

Figure 11 is the 11-11 sectional drawing of Fig. 4.

Figure 12 is the 12-12 amplification profile of Fig. 5.

Figure 13 is the 13-13 sectional drawing of Fig. 5.

Figure 14 is the 14-14 amplification profile of Fig. 2.

Figure 15 is the 15-15 sectional drawing of Figure 14.

Figure 16 is the 16-16 sectional drawing of Figure 14.

Figure 17 is the 17-17 sectional drawing of Figure 14.

Embodiment

Below, the one embodiment of the invention shown in illustrate embodiments of the present invention with reference to the accompanying drawings

Fig. 1～Figure 17 represents one embodiment of the invention, Fig. 1 is the side view of motor scooter type motor-driven cart, Fig. 2 has omitted the vehicle body cover and has accommodated the two-wheeled intermediate portion stereogram of small-sized motor type under the case state, Fig. 3 is the 3-3 amplification profile of Fig. 1, Fig. 4 be Fig. 34 to diagrammatic sketch, Fig. 5 be Fig. 35 to diagrammatic sketch, Fig. 6 is the 6-6 sectional drawing of Fig. 3, Fig. 7 is the figure that sees housing from cylinder head side.Fig. 8 is the 8-8 sectional drawing of Fig. 7, Fig. 9 is the 9-9 amplification profile of Fig. 6, Figure 10 is the 10-10 sectional drawing of Fig. 9, Figure 11 is the 11-11 sectional drawing of Fig. 4, and Figure 12 is the 12-12 amplification profile of Fig. 5, and Figure 13 is the 13-13 sectional drawing of Fig. 5, Figure 14 is the 14-14 amplification profile of Fig. 2, Figure 15 is the 15-15 sectional drawing of Figure 14, and Figure 16 is the 16-16 sectional drawing of Figure 14, and Figure 17 is the 17-17 sectional drawing of Figure 14.

At first in Fig. 1 and Fig. 2, the vehicle frame 25 of equipment of small motor cart has main frame pipe 27, transverse tube 28,

back framework pipe

29,30, this main frame pipe 27 is being fixed head pipe 26 at its front end, this transverse tube 28 is vertically fixed on the rear end of this main frame pipe 27, and this back framework pipe the 29, the 30th, front end connect framework component after the pairing left and right at the two end part that are arranged on transverse tube 28 respectively.

Main member pipe 27 is stretched structural portion 27a by being connected with down integratedly, end structural portion 27b forms, and stretches structural portion 27a under this and from the beginning manages 26 and have a down dip backward, and this end structural portion 27b rearward extends from the approximate horizontal ground, rear end of stretching structural portion 27a down.In addition, the

back framework pipe

29,30 of pairing left and right by connection integratedly rising

structural portion

29a, 30a is set and the 29b of upper framework portion, 30b form, this rising

structural portion

29a, 30a extend to the back upper place from the two end part of above-mentioned transverse tube 28, when the 29b of this upper framework portion, 30b rearward extend from the rear end approximate horizontal ground of rising

structural portion

29a, 30a, in horizontal plane, carry out bending so that open-ended thereafter mutually relatively.

On above-mentioned head pipe 26, can support front fork 31 with turning to, stride front-wheel WF on this front fork 31, connect steering tiller 32 in the upper end of front fork 31.

The front portion of two

back framework pipes

29,30 in vehicle frame 25 is by linkage mechanism can joltily support power unit P about in the of 33 front portion, and the trailing wheel WR that is configured in the right side, rear portion of this power unit P is bearing in the rear portion of power unit P with axle.

In Fig. 3～Fig. 6, power unit P is made of motor E and electrodeless variable-speed motor M, and this motor E is the forced air-cooled single cylinder four stroke engine that is configured in the place ahead of trailing wheel WR, and this stepless speed changer M is arranged between this motor E and the above-mentioned trailing wheel WR.

The engine body 34 of motor E has crankcase 35, be combined in cylinder block 36 on the crankcase 35, be combined in cylinder head 37 on the cylinder block 36, be combined in housing 38 on the cylinder head 37 at the opposition side with cylinder block 36 with crankcase 35 opposition sides, this engine body 34 is configured between the two

back framework pipes

29,30 of vehicle frame 25, and cylinder head 37 is configured between the bottom of rising structural portion 29a, the 30a of

framework pipes

29,30 after two.

The structure of cylinder block 36 is, the axis that is located at the cylinder bore diameter 39 on this cylinder block 36 be cylinder-bore axis C along two-wheeled fore-and-aft direction a little forward updip tiltedly be configured to approximate horizontal, cylinder head 37 and free sliding be entrenched between the piston 40 in this cylinder bore diameter 39 and forming firing chamber 41.In addition, piston 40 is connected with bent axle 44 by connecting rod 42 and crank pin 43, and this bent axle 44 has the spin axis parallel with the spin axis of trailing wheel WR.

Bent axle 44 by crankcase 35 free rotary ground supportings, this crankcase 35 by when comprising above-mentioned cylinder-bore axis C, with the plane of the axis normal of this bent axle 44 in combined a pair of

chest portion

35a, 35b constitute, bent axle 44 folder between a side box component 35a and bent axle 44 is established first ball bearing 45, and presss from both sides between the opposing party's box component 35b and bent axle 44 and establish second ball bearing 46.

On the upper side of cylinder head 37, be provided with the inlet hole 47 that can be communicated with, on the lower side of cylinder head 37, be provided with the exhaust port 48 that can be communicated with above-mentioned firing chamber 41 with above-mentioned firing chamber 41.The suction valve 49 that opens and closes inlet hole 47 and exhaust port 48 respectively and outlet valve 50 on the projection drawing of projection on the plane vertical with the spin axis of bent axle 44 roughly V word shape ground be provided on the cylinder head 37 with arranging, suppressed to the direction of closing inlet hole 47 and exhaust port 48 respectively.In addition, the spark plug 51 that faces with firing chamber 41 is installed at least one side side in the left and right side of cylinder head 37, is to be installed on the side on right side with the state towards two-wheeled direct of travel the place ahead in this embodiment.

Accommodating the valve actuating gear 52 of above-mentioned suction valve 49 of driven for opening and closing and outlet valve 50 between cylinder head 37 and housing 38, this valve actuating gear 52 has camshaft 55, air inlet side and exhaust side

pitman arm shaft

56,57, air inlet side Rocker arm 58, exhaust side Rocker arm 59; This camshaft 55 has the axis with the parallel axes of bent axle 44, and be supported on the cylinder head 37, and have with rotating freely air inlet with and exhaust with

cam

53,54; This air inlet side and exhaust side

pitman arm shaft

56,57 have the axis parallel with camshaft 55 and are supported on the cylinder head 37; This air inlet side Rocker arm 58 is driven in above-mentioned air inlet and drives suction valve 49 with cam 53, and freedom joltily is supported on the air inlet side pitman arm shaft 56; This exhaust side Rocker arm 59 is driven in above-mentioned exhaust and comes driven for opening and closing outlet valve 50 with cam 54, and freedom joltily is bearing on the exhaust side pitman arm shaft 57.

Fixing in an end of camshaft 55 by movable sprocket 60.In addition, on bent axle 44, foreign side's side of second ball bearing 46 with above-mentioned by the corresponding fixed-site driving sprocket wheel 61 of movable sprocket 60, drive and by

movable sprocket

61,60 on around hanging ring-type cam chain 62, cam chain 62 can be incorporated in the accommodation chamber 63 with walking, and this accommodation chamber 63 forms along cylinder block 36, cylinder head 37 and housing 38.By such driving sprocket wheel 61, by movable sprocket 60 and cam chain 62 1/2 rotating speed rotation drive cam shaft 55 with the rotating speed of bent axle 44.

Foreign side's side at first ball bearing 45, on bent axle 44, fixing actuation gear 64, be installed on the crankcase 35 by the oil pump 66 that oil strainer 79 sucts oil from the oily reservoir 65 that is formed at the bottom in the crankcase 35, this oil pump 66 is driven by above-mentioned actuation gear 64.

The part of the oil of discharging from this oil pump 66 is used for lubricated valve actuating gear 52, is provided with the oil that is used for the oil from oil pump 66 is directed into valve actuating gear 52 and supplies with road 67 on crankcase 35, cylinder block 36, cylinder head 37 and housing 38.And, in cylinder head 37, at position configuration oil supply passage 67, in this embodiment than exhaust port 48 more close inlet holes 47, to with the plane of the axis normal of bent axle 44 on the projection drawing of projection, with inlet hole 47 crossover locations on the oily supply passage 67 of configuration.

Simultaneously with reference to Fig. 7 and Fig. 8, the downstream end of above-mentioned oily supply passage 67 is by circulation groove 68 and have the opening 69 at the end to constitute, this circulation groove 68 is arranged in order to supply to an end from the oil of cylinder head 37 sides on housing 38 and the junction plane that cylinder head 37 combines, above-mentioned opening 69 links to each other with the other end of above-mentioned circulation groove 68 and is located on the sidewall of housing 38, the spraying hole 70 that links to each other with the inner end of opening 69 is located on the side wall inner surface of housing 38, is used for towards valve actuating gear 52 ejection oil.

Being provided with the end that has that links to each other with an end of above-mentioned circulation groove 68 on housing 38 detects hole 71, and in position integratedly outstanding the be provided with mounting boss 72 corresponding with this detection hole 71, this mounting boss 72 is outstanding to foreign side from the outer surface of housing 38, on this mounting boss 72 Temperature Detector 73 is installed, this Temperature Detector 73 is projected in the above-mentioned detection hole 71 73a of its Detecting element portion.That is, Temperature Detector 73 makes the 73a of Detecting element portion face oily supply passage 67 ground to be installed on the housing 38 of engine body 34.

With reference to Fig. 3, foreign side at above-mentioned actuation gear 64 is setting generator 76, this generator 76 has the stator 74 that is fixed on the crankcase 35 and around this stator 74 and be fixed on external rotor 75 on the bent axle 44, in the foreign side of this generator 76, is fixing fan 77 on bent axle 44.This fan 77 is to be fixed in by a plurality of for example 4

bolts

78,78... on the peripheral part of the base portion 77a on the external rotor 75 of generator 76 a plurality of

blade

77b, 77b... to be set integratedly and to form.

The part of cylinder block at least 36 in the engine body 34 and cylinder head 37, crankcase in this embodiment 35, cylinder block 36 and cylinder head 37 are covered with by guard shield 82, flow through the circulation flow path 81 that is formed between engine body 34 and the guard shield 82 with air from the forced air cooling that fan 77 is discharged.And, a plurality of cooling fan 36a..., 37a... are being set respectively on the outside of cylinder block 36 and cylinder head 37 highlightedly, be used for and can cool off expeditiously by the cooling air that is flowing in above-mentioned circulation flow path 81.

Above-mentioned guard shield 82 is by becoming a pair of top and

lower cover parts

83,84 and fan guard 85 to constitute up and down, this top and

lower cover parts

83,84 are mutually combined and are come common coating gas cylinder body 36 and cylinder head 37, said fan cover 85 is combined on above-mentioned two

cap assemblies

83,84, and the part of covering crankcase 35, upper lid parts 83, lower cover parts 84 and fan guard 85 are formed by synthetic resin respectively.

A plurality of engagement pawl 87... are being set on upper lid parts 83 highlightedly, these a plurality of engagement pawl 87... are side-prominent to bottom cap assembly 84 with the junction plane 86 of lower cover parts 84 from above-mentioned upper lid parts 83, are provided with the 88... of fastening portion that makes above-mentioned each engagement pawl 87... elasticity combination on lower cover parts 84.In addition, the a plurality of 89... of portion, 90... of being connected are set respectively on top and

lower cover parts

83,84 integratedly, these a plurality of 89... of portion, 90... of being connected are in contact with one another at junction plane 86, and the 89... of the portion that is connected, the 90... that are in contact with one another interconnect with bolt member 91....

Since make in this wise engagement pawl 87... towards the elasticity of the 88... of fastening portion in conjunction with and by being connected top and

lower cover parts

83,84 being mutually combined of the 89... of portion, 90... by the connection of bolt member 91..., housing 38 from top and

lower cover parts

83,84 forwards side-prominent.

Fan guard 85 is connected on the case member 35a, covers case member 35a and fan 77 as the part of crankcase 35, is connected on above-mentioned top and the

lower cover parts

83,84 by a plurality of bolt component 92....

Be provided with attraction tube 94 accordingly in its foreign side and fan 77 on this fan guard 85, this attraction tube 94 is formed for drawing towards said fans 77 side draughts from the outside attraction mouth 93 of air, is attracting to be provided with shutter board 95 on the mouth 93.

This shutter board 95 by with a plurality of for example 4 the ring portion 95a～95d that attract tube 94 concentric arrangement, radially extend and is connected attract tins 94 and each ring portion 95a～95d between a plurality of joint 95e... constitute, on the position corresponding, the timing marks 96 of for example triangle of the phase place that is used to proofread and correct bent axle 44 at the inner face subscript of fan 85 with one of these a plurality of joint 95e....This timing marks 96 is to be used to proofread and correct the timing of usefulness of for example lighting a fire, consistent by being used in that fan 77 is fixed among a plurality of for example 4 bolt 78... on the bent axle 44 with the joint 95e in the above-mentioned shutter board 95 corresponding to timing marks 96, can easily light a fire with the Phase correction of timing.

Above-mentioned timing marks 96 not only can be used to proofread and correct the timing of igniting usefulness, but also the timing that can be used to proofread and correct TDC and BDC, and valve actuating gear 52 also can be used to proofread and correct the timing of its acting characteristic change when at least one side's who constitutes variable suction valve 49 and outlet valve 50 acting characteristic.

With reference to Fig. 9 and Figure 10, on the upper side of cylinder head 37, be provided with the smooth attachment face 97 that makes inlet hole 47 openings simultaneously, on this attachment face 97, clip the downstream that thermal insulation barriers 99 ground are connecting suction tude 98.

Downstream in suction tude 98 is being provided with lip part 98a integratedly, and thermal insulation barriers 99 and above-mentioned attachment face 97 with the inlet hole 100 that is communicated with inlet hole 47 have and above-mentioned lip part 98a corresponding shape.

Packing ring 101,102 round above-mentioned inlet hole 100 is installed on the two sides of thermal insulation barriers 99 annularly, and folder is being established a square washer 101 between thermal insulation barriers 99 and attachment face 97, presss from both sides between thermal insulation barriers 99 and above-mentioned lip part 98a and establishes packing ring 102.And the thickness T of thermal insulation barriers 99 is set greatlyyer than the interval S between the upper lid parts 83 in attachment face 97 and the guard shield 82.

Both sides at inlet hole 47, on attachment face 97, be provided with the screw hole 103,103 at the end, the bolt 104,104 that passes flange 98a and thermal insulation barriers 99 is combined in above-mentioned each screw hole 103,103 by screw thread, by tighting a bolt 104,104, and suction tude 98 is connected on the attachment face 97 by thermal insulation barriers 99.

Be provided with the opening portion 105 that is used for the above-mentioned thermal insulation barriers 99 in chimeric location on the upper lid parts 83 in the guard shield 82 of coating gas cylinder cap 37.This opening portion 105 is bigger than thermal insulation barriers 99 as shown in figure 10, is forming to be used for flowing through the exhaust port 106 that the tempering air that comes is discharged to the outside by circulation flow path 81 between the local side that reaches thermal insulation barriers 99 on the local side of above-mentioned opening 105.

The upstream extremity of above-mentioned suction tude 98 is connected with the downstream of the vaporizer 108 at the rear that is configured in this suction tude 98 by connecting flexible pipe 107, and the upstream extremity of vaporizer 108 is connected on the air-strainer 110 of the left side side that is configured in trailing wheel WR by connecting tube 109.

In Figure 11, on vaporizer 108, set up the motorcycle starter 111 that is energized control according to the checkout value of said temperature detector 73, this motorcycle starter 111 is installed on the vaporizer body 112, be used to open and close and employ mixed gas path 113 midway, the air throttle that these mixed gas path 113 circuitous vaporizers 108 are had is located on the vaporizer body 112 of vaporizer 108 (not shown).

Employ in the mixed gas path 113 at above-mentioned, fixing discharge piping on vaporizer body 112, this discharge piping 114 is folded on the part of upstream side of motorcycle starter 111.Fixing the fuel nozzle 115 that the bottom that makes this discharge piping 114 protrudes into top in the bottom of vaporizer body 112.And, fixing the fuel tank 116 that is used for storage of fuels in the bottom of vaporizer body 112, the outstanding fuel that enters in the fuel tank 116 in the bottom of above-mentioned fuel nozzle 115.

Motorcycle starter 111 has needle-valve 118, this needle-valve 118 more is being inserted into with freely advancing and retreat and has been located in the nozzle midway 117 of employing mixed gas path 113 in the downstream side than discharge piping 114, the position of needle-valve 118 in nozzle 117 decided by the energising control of motorcycle starter 111, thus, determined to have circulated and employed the amount that rising of mixed gas path 113 employed mixed gas.

Between the mating face 86 of the top of a part that constitutes guard shield 82 and

lower cover parts

83,84, forming embedding hole 120.And the spark plug cap 121 that is connected with spark plug 51 embedding hole 120 around have the lip part 121a that contacts with the outside of top and

lower cover parts

83,84, this spark cap 121 is entrenched in the above-mentioned embedding hole 120.

In addition, be provided with penthouse 122 integratedly on the upper lid member 83 in top and

lower cover parts

83,84, this penthouse 122 covers spark plug cap 121 towards the chimeric embedding part of embedding hole 120 from the top, as shown in figure 12, front end at this penthouse 122 is forming spline positioning part 122a, and this spline positioning part 122a contacts with the front end of this penthouse 122 in conjunction with the axis rotation that stops this spark plug cap 121 around spark plug 51 by making spark plug cap 121.

Above-mentioned penthouse 122 covers spark plug cap 121 to the chimeric embedding part of embedding hole 120 from the top, this spark plug cap 121 is the posture that at least a portion of the high-tension busbar 123 that will be connected with spark plug cap 121 is forwards extended from spark plug cap 121, spline positioning part 122a is formed on the penthouse 122, be used for resisting from the elastic force of high-tension busbar 123 effects, given the spark plug cap 121 of rotation trend from the elastic force of high-tension busbar 123 effects to a side around the axis of spark plug 51 thereby accept.

Simultaneously with reference to Figure 13, on upper lid parts 83, form the retaining member fitting seat 125 that is connected continuously with above-mentioned penthouse 122, using the retaining member 124 that flexibly is installed on this retaining member fitting seat 125 to keep the high-tension busbar 123 that links to each other with above-mentioned spark plug cap 121.

Engine body 34 is supported on the vehicle frame 25, cylinder head 37 is provided between the bottom of rising structural portion 29a, the 30a of the front portion in the

framework pipe

29,30 after the pairing left and right, above-mentioned spark plug cap 121 also is configured between the bottom of two rising

structural portion

29a, 30a, is supporting spark coil 126 as illustrated in fig. 2 on the top as the rising structural portion 30a on the side's of two rising

structural portion

29a, 30a right side.

High-tension busbar 123 the other ends that link to each other with an end and spark coil 126 from the place ahead of the above-mentioned spark plug cap 121 of spline positioning part 122a combination the turning back and be connected of U word shape roughly rearward with spark plug cap 121.

Simultaneously with reference to Figure 14～Figure 17, be provided with a pair of hook 128 on the upper lid member 83 in guard shield 82 integratedly, 128 and a pair of connecting wall 129,130, this hook 128,128 have to mutually approaching side-prominent in conjunction with protuberance 128a at its front end, 128a, and the outside from upper lid parts 83 in the time of relative mutually erects, above-mentioned a pair of connecting wall 129,130 connect above-mentioned two hooks 128, between 128, and mutually relatively erect from the outside of upper lid parts 83, on upper lid member 83, be provided with by above-mentioned hook 128 simultaneously, 128 and connecting wall 129, the tetragonal open-work 131 in 130 right angles that surround.

Two hooks 128,128 in conjunction with

protuberance

128a, 128a and above-mentioned two connecting walls 129,130 between clamping the long size parts of a plurality of flexibility, the long size parts of this flexibility are stacked mutually and be pressed between above-mentioned two hooks 128,128, in this embodiment, the long size parts of the flexibility of interior side's side of being accepted by two connecting walls 129,130 are that the flexibility of foreign side's side of contacting with its outside in conjunction with

protuberance

128a, 128a of cable 133 and above-mentioned two is grown the size parts and promptly managed 134 and be clamped in conjunction with between

protuberance

128a, 128a and two connecting walls 129,130.

Above-mentioned cable 133 has soft vinyl resin foreskin and links to each other with Temperature Detector 73, and the aforementioned tube that formed by the elastic material of hard 134 is connected with skull 38 in order to guide ventilation gas.

And, above-mentioned hook 128 is made of baseplate part 128b and a plurality of for example two the board 128c of branch, 128c, its base end part of this baseplate part 128b links to each other with upper lid parts 83 with its total length, the above-mentioned board 128c of branch, 128c are at cable 133 and manage on 134 the length direction and for example linking to each other with the 128b of aforesaid substrate portion at two positions across a plurality of positions at interval, and are being provided with above-mentioned in conjunction with protuberance 128a on its front end highlightedly.Between each board 128c of branch, 128c span two hooks 128,128, be provided with in 129,130 reinforced walls 132 of bearing cable 133 of two connecting walls.

Can't help to connect outlet pipe 118 on the lower side of above-mentioned guard shield 82 coating gas cylinder caps 37, the upstream extremity of this outlet pipe 118 links to each other with exhaust port 48, is connecting the downstream of outlet pipe 118 on the muffler 119 on the right side that is configured in trailing wheel WR.

Particularly with reference to Fig. 3 and Fig. 4, connecting transmission case 136 on crankcase 35, this transmission case 136 stretches out to the left side side of trailing wheel WR with the state towards two-wheeled walking the place ahead.This transmission case 136 is made of box main body 137, left side cover 138, right side cover 139, this box main body 137 connects the case member 35b that is arranged on above-mentioned crankcase 35 integratedly and goes up also extension rearward, this left side cover 138 its with above-mentioned box main body 137 between formation first Transmission Room 140, and be connected on the box main body 137 from the left side, above-mentioned right side cover 139 its with above-mentioned box main body 137 between formation second Transmission Room 141, and be connected the rear portion, right side of box main body 137.

The front portion of the box main body 137 in transmission case 136 is outstanding to be provided with supporting arm 142, and this supporting arm 142 is configured in the side of the cylinder block 36 among the motor E, and this supporting arm 142 can joltily be bearing on the vehicle frame 25 by linkage mechanism 33.

But axletree 143 free rotary ground supportings of trailing wheel WR are on the rear portion and right side cover 139 of the box main body 137 of transmission case 136.As shown in Figure 1, between the 29a of upper framework portion in the back framework pipe 29 of the rear portion of box main body 137 and vehicle frame 25 posterior bumper 144 is set.

Stepless speed changer M is the V-shape belt formula stepless speed changer that is accommodated in first Transmission Room 140, is provided with reduction gear row 145 between stepless speed changer M and axletree 143.

Stepless speed changer M has driving side transmission pulley 146 and passive side transmission pulley 149 and is hung around ring-type V-shape belt 150 on two transmission pulleys 146,149, this driving side transmission pulley 146 is connected with the end of bent axle 44 in the foreign side of second ball bearing 46, and this passive side transmission pulley 149 has the axis parallel with bent axle 44 and is installed in free rotary ground supporting on the rear portion and the driven axle 147 on the right side cover 139 of box main body 137 by centrifugal clutch 148.

Driving side transmission pulley 146 is made of the movable half-pulley 146b that is fixed on the fast pulley halfbody 146a on the bent axle 44 and can be installed in axially slidably on the bent axle 44.Between two half-

pulley

146a, 146b, form the annular slot 151 of V word shape, in this annular slot 151, inserting V-shape belt 150.In addition, the back side at movable half-pulley 146a is fixedly mounting skewback 152 on bent axle 44, is accommodating with quick condition 152 of movable half-pulley 146a and skewbacks and is a plurality ofly heavyly rolling 153.When the rotating speed of bent axle 44 increased, the 153 radial direction foreign sides to bent axle 44 of heavily rolling that are subjected to centrifugal force moved and make movable belt radius 146a and fast pulley halfbody 146b approaching.Thus, contact radius V-shape belt 150 and two half-

pulley

146a, 146b becomes big.

In addition, passive side transmission pulley 149 has carrying cylinder 154, fast pulley halfbody 149a, movable half-pulley 149b; This carrying cylinder 154 is connected on the driven axle 147 by centrifugal clutch 148, and free rotary ground supporting is on driven axle 147; This fast pulley halfbody 149a is formed on this carrying cylinder 154, this movable half-pulley 149b can be with respect to said fixing half-pulley 149a near separating, and be bearing on the carrying cylinder 154, quilt inserts V-shape belt 150 to suppressing near the direction of fast pulley halfbody 149a in the annular slot 155 that is formed on the V word shape between two half-pulley 149a, the 149b simultaneously.Fast pulley halfbody 149a is along with the contact radius of V-shape belt 150 with driving side transmission pulley 146 becomes greatly, so that the mode that the contact radius with slave end transmission pulley 149 of this V-shape belt 150 diminishes moves axially to movable belt pulley 149b, thus, carry out stepless change between bent axle 44 and the driven axle 147 corresponding to the rotation of bent axle 44.

Free rotary ground supporting recoil axle 156 on the left side cover 138 in transmission case 136, in the outer end of this recoil axle 156 recoil pedal 157 (with reference to Fig. 1) is set.In addition, in the inner face side of above-mentioned left side cover 138, be provided with backflushing type starting arrangement 158 between recoil axle 156 and bent axle 44, this backflushing type starting arrangement 158 can arrive bent axle 44 with the transmission of power corresponding to the recoil axle 156 of the pedaling action of recoil pedal 157.

Reduction gear row 94 are located between driven axle 147 and the axletree 143, and are accommodated in second Transmission Room 141, are passed to the axletree 143 of trailing wheel WR after the rotating power of the driven axle 147 among the stepless speed changer M is slowed down by reduction gear row 94.

Between the front portion of two

back framework pipes

29,30 in vehicle frame 25 be configured in above-mentioned motor E above mode supporting the containing box 160 that can take in the helmet etc., between the rear portion of two

back framework pipes

29,30, supporting fuel tank 161.

Secondary air air-strainer 162 is being supported in the front portion of the 29b of upper framework portion behind the left side in two

back framework pipes

29,30 in the framework pipe 29, and this secondary air is used to purify the secondary air of the exhaust port 48 that supplies to motor E with air-strainer 162.Connecting the downstream of suction tude 163 at this secondary air with the suction port of air-strainer 162, the upstream extremity of this suction tude 163 is inserted into the rearward end of the 30b of upper framework portion in the framework pipe 30 behind the right side in the two

back framework pipes

29,30.

Being located at motor E and secondary air is supporting with the supporting member 165 of the secondary air control valve between the filter cleaner 162 164 by the top of the rising structural portion 29a of the back framework pipe 29 that is installed in the left side.

The bottom of rising structural portion 29a in the back framework pipe 29 in left side be provided with this rising structural portion 29a in the connecting tube portion 166 that is communicated with, the conduit 167 that is used for deriving cooling air in the stepless speed changer M of power unit P is connected above-mentioned connecting tube portion 166.

Vehicle frame 25 is covered by plastic car body cover 168, and this car body cover 168 has the pedal bottom plate 170 of the legging cover 169 in the place ahead that covers driver's leg, the pin that is used for the mounting driver that links to each other with the bottom of legging cover 169, link to each other with this pedal bottom plate 170 and from the side cover 171 at covering body rear portion, both sides.

Be provided with vehicle seat 172 on side cover 171, this vehicle seat 172 can open and close containing box 160 and fuel tank 161 ground opening and closing cover containing box 160 and fuel tanks 161 from the top.

Then the effect to this embodiment describes, the oil pump 66 that the oily reservoir 65 that is used in the crankcase 35 sucts oil is installed on the crankcase 35 of engine body 34, the oily supply passage 67 that guiding is used for the oil of lubricated valve actuating gear 52 links to each other with oil pump 66 and is located at crankcase 35, cylinder block 36, cylinder head 37 and housing 38, and Temperature Detector 73 makes the 73a of its Detecting element portion face oily supply passage 67 ground and is installed on the engine body 34.

The oily supply passage 67 of the oil that guiding is discharged from oil pump 66 for lubricated valve actuating gear 52, so long as engine running is how all oily abrim operating condition and posture be, face the 73a of Detecting element portion of its oily supply passage 67 ground configuration Temperature Detector 73 as described above, when can the utmost point being difficult to be subjected to the influence of variation of the operating condition of motor E and posture, can correctly and promptly detect engine temperature frequently, and detecting oil temperature by Temperature Detector 73 does not need complicated structure.

And, because oily supply passage 67 is configured in the position than exhaust port 48 more close inlet holes 47 on cylinder head 37, when therefore, being difficult to be subjected to influence from the heat radiation of the outer surface portion of engine body 34, can be correctly and promptly detect engine temperature.

In addition, owing to motor E is constituted forcedly air-cooled engine on cylinder block 36 and cylinder head 37 in the mode that cooling fan 36a..., the 37a... of air-cooled usefulness are set, Temperature Detector 73 is installed on the housing 38 that is not provided with air-cooled fan, therefore, can not be cooled fan 36a..., 37a... brings influence ground correctly to detect engine temperature, and it is also simple to be used to install the structure of Temperature Detector 73.

Since with vaporizer 108 that inlet hole 47 is connected on be installed with and be used to open and close the motorcycle starter 111 of employing mixed gas 113 that is located on this vaporizer 108, this motorcycle starter 111 is energized control according to the checkout value of Temperature Detector 73, therefore, can can improve the warming-up performance of motor E according to make the mixed gas optimization that supplies to motor E when starting by the correctly detected engine temperature of Temperature Detector 73.

In addition, cylinder block 36 and cylinder head 37 are used to make the circulation flow path 81 of forced air cooling with air ventilation by guard shield 82 coverings that are formed between cylinder block 36 and the cylinder head 37, mode with the influence of the cooling air that is not forced to blow is installed Temperature Detector 73 on housing 38, though be that forced air cold engine also can detect correct engine temperature thus.

On the upper side of cylinder head 37, be provided with the smooth attachment face 97 that makes inlet hole 47 openings, on this attachment face 97, clip the connection suction tude 98 of thermal insulation barriers 99, on the upper lid member 83 of guard shield 82, be provided with opening portion 105 chimeric, location thermal insulation barriers 99.

Therefore, by it is entrenched in the opening portion 105, thermal insulation barriers 99 is positioned and remains on the guard shield 82, and, thermal insulation barriers 99 plays the function of guide bolt 104..., and these bolt 104 screw threads are combined among the screw hole 103... on the attachment face 97 that is located at cylinder head 37, therefore, bolt 104... is easy to the screw thread combination of screw hole 103..., fastening transfiguration, can improve assembling performance.

In addition, owing between a part of side of a part of inner side surface that is located at the opening portion 105 on the upper lid member 83 that constitutes by synthetic resin and thermal insulation barriers 99, forming exhaust port 106, therefore by using the hot blast heating air inlet pipe 98 of discharging to improve the warming-up performance from exhaust port 106.And, the metal mold that is used to form opening portion 105 when the mould-forming upper lid member 83 partly can be made relatively and be maximized, make this metal mold partly comprise the part corresponding, can improve intensity, can help to improve the life-span of metal mold thus with said exhaust mouth 106.

And, the thickness T of thermal insulation barriers is set greatlyyer than the interval of 82 of attachment face 97 and guard shields, therefore be entrenched on the attachment face 97 in the opening portion 105 by thermal insulation barriers 99 is pressed against, can prevent that thermal insulation barriers 99 comes off from guard shield 82 when assembling, can improve assembling performance more.

Guard shield 82 has that the quilt of common coating gas cylinder cap 36 and cylinder head 37 mutually combines becomes a pair of top and

lower cover member

83,84 up and down, be used for 86 on the mating face that the chimeric embedding hole 120 that is connected the spark plug cap 121 on the spark plug 51 is formed on two

cap assemblies

83,84, this spark plug 51 is installed on the right flank of cylinder head 37.And, be provided with integratedly on the upper lid parts 83 from above cover the penthouse 122 of spark plug cap 121 to the chimeric embedding part of embedding hole 120, this spark plug cap 121 is in the posture that at least a portion of the high-tension busbar 123 that will be connected with spark plug cap 121 is forwards extended from spark plug cap 121.By from the elastic force of high-tension busbar 123 effect to the spark plug cap 121 around side's bias voltage of the axis of spark plug 56 contact with spline positioning part 122a, combination, this spline positioning part 122a is formed on the penthouse 122, is used to resist above-mentioned resilient support and lives spark plug cap 121.

Therefore, because at least a portion of high-tension busbar 123 is forwards extended from spark plug cap 121, therefore, even the interval between the back framework pipe 30 in the outside that is configured in spark plug cap 121 in spark plug cap 121 and the vehicle frame 25 is narrow, also can avoid interfering, can increase the degrees of freedom of configuration high-tension busbar 123, even simultaneously under the situation of curved configuration high-tension busbar 123 with vehicle frame 25, also can set its bending radius, the life-span that can improve high-tension busbar 123 than significantly.

Spark plug cap 121 is owing to contacted and be combined on the spline positioning part 122a that is formed on the penthouse 122 by the elastic force from high-tension busbar 123 effects, therefore, can prevent that spark plug cap 121 is around the rotational of spark plug 51 in engine running, can prevent the vibration of high-tension busbar 123 thus, can prevent effectively that high-tension busbar 123 from contacting with other part.

And, owing to cover spark plug cap 121 from the top to the chimeric embedding part of embedding hole 120 by penthouse 122, therefore, can not make since with the member of engine body 34 tops for example on the joint such as containing box 160 collisions and fallen muddy water etc. attached to high-tension busbar 123 and spark plug cap 121.

In addition, keep the retaining member 124 of high-tension busbar 123 owing to be installed in and be connected with penthouse 122 and be formed on the retaining member fitting seat 125 on the upper lid parts 83, therefore, can near spark plug cap 121, keep high-tension busbar 123, thereby can prevent the vibration of high-tension busbar 123 more effectively, can increase the intensity of penthouse 122 by retaining member fitting seat 125.

In addition, engine body 34 in side-looking with cylinder head 37 and rising structural portion 29a, the bottom of 30a is configured in above-mentioned two back framework pipes 29 accordingly, between 30, and can be bearing on the vehicle frame 25 with fluctuating, this rising

structural portion

29a, 30a is arranged on

back framework pipe

29,30 anterior also tilts to the back upper place, be bearing in above-mentioned two back framework pipes 29 at the rear of cylinder head 37, an end that is connecting high-tension busbar 123 on the spark coil 126 on 30 the side 30, the other end of this high-tension busbar 123 from being connected with spark plug cap 121 with the back of rearward roughly turning back, the place ahead of the spark plug cap 121 of spline positioning part 122a combination U word shape.

According to such configuration, can be when avoiding high-tension busbar 123 and vehicle frame 25 to interfere drawing high-tension busbar 123 easily, can more positively improve the crooked durability of high-tension busbar 123.

In addition, on the upper lid member 83 of guard shield 82, be provided with a pair of hook 128,128 and a pair of connecting wall 129,130 integratedly, and be provided with by these hooks 128,128 and connecting wall 129,130 round the tetragonal open-work 131 in right angle, above-mentioned a pair of hook 128,128 front end have to mutually near side-prominent in conjunction with

protuberance

128a, 128a, and mutually relatively erect from the outside of upper lid member 83, above-mentioned a pair of connecting wall 129,130 connects between above-mentioned two hooks 128,128, relatively erect from the outside of upper lid member 83 mutually simultaneously.

Two hooks 128,128 in conjunction with

protuberance

128a, 128a and 129,130 clamping cables 133 of above-mentioned two connecting walls and manage 134, this cable 133 and manage 134 and be pressed between above-mentioned two hooks 128,128 mutually stackedly.

Therefore, when the upper lid member 83 that mould-forming is formed by synthetic resin, a pair of hook 128,128 and a pair of connecting wall 129,130 integratedly can be shaped with the simple mold structure that does not use sliding formwork, do not use the two-wheeled upper lid member that has 83 parts in addition, with two hooks 128,128 and two connecting walls 129,130 supporting cable 133 and manage 134 stably just, can be when realizing that number of spare parts and installation exercise have reduced man-hour, can obtain cable 133 and manage 134 stable support toward the tabular surface of upper lid members 83.

And open-work 131 is by overlapped cable 133 and manage 134 and cover, at supporting cable 133 and manage under 134 the state to see in the upper lid parts 83 being in the guard shield 82 from above-mentioned open-work 131.

Promptly, open-work 131 is by stacked mutually cable 133 and manage 134 coverings, can prevent to leak cooling air from guard shield 82, can stably keep the cooling performance of forced air cooling type motor E thus, simultaneously can and manage 134 at guard shield 82 upper support cables 133, and can prevent to leak cooling airs from open-work 131, so dust can not be ejected into the outer surface side of guard shield 82, thus can prevent to reduce aesthetic appearance.

Above-mentioned cable 133 has soft vinyl resin foreskin and links to each other with Temperature Detector 73, and aforementioned tube 134 is formed by the elastic material of hard in order to guide ventilation gas, and be connected with head-shield 38, the vinyl resin foreskin of the outside of cable 133 is closely contacted fully on two connecting walls 129,130, make positively being combined on pipe 134 the outside of front end of two hooks 128,128 simultaneously, thus supporting cable 133 and manage 134 more positively in conjunction with

protuberance

128a, 128a.

And above-mentioned hook 128 is by baseplate part 128b and a plurality of for example two board 128c of branch, 128c forms, its base end part of this baseplate part 128b links to each other with upper lid member 83 with its total length, above-mentioned two board 128c of branch, 128c at cable 133 and a plurality of positions of managing devices spaced apart on 134 the length direction for example two positions with when the 128b of aforesaid substrate portion links to each other, be provided with highlightedly at front end above-mentioned in conjunction with protuberance 128a, at two connecting walls 129,130 reinforced walls 132 of accepting cable 133 are at each board 128c of branch, 128c span two hooks 128,128 ground are set up.

Therefore, because the cable 133 of side in also being born by reinforced wall 132, therefore more stably supporting cable 133 and pipe 134 can be increased the intensity of two hooks 128,128 simultaneously by reinforced wall 132.

Embodiments of the invention more than have been described, but the present invention is not limited to the foregoing description, under the situation of the invention that the claim that does not break away from the application is put down in writing, can carries out all design alterations.

As mentioned above, according to first technological scheme of the present invention, because at least a portion of high-tension busbar is forwards extended from spark plug cap, therefore even spark plug cap is narrow with the interval between the framework member that is configured in outside the spark cap, also can avoid the interference of high-tension busbar and vehicle frame, thereby can increase the degrees of freedom of configuration high-tension busbar, even and when disposing high-tension busbar agley, thereby because than setting the life-span that its bending radius can improve its high-tension busbar significantly.Since the spark cap flexibly butt, be incorporated on the spline positioning part, can prevent that spark plug cap is around the rotational of spark plug in engine running, the vibration of high-tension busbar can be prevented thus, thereby contacting of this high-tension busbar and other part can be prevented effectively.And, owing to cover spark plug cap to the chimeric embedding part of embedding hole from the top, therefore, can make collision on the parts above the engine body and fallen muddy water etc. are non-cohesive on the joint of high-tension busbar and spark plug cap by penthouse.

According to a second technical aspect of the present invention,, the vibration of high-tension busbar can be prevented more effectively, the intensity of penthouse can be increased by the retaining member fitting seat by near spark plug cap, keeping high-tension busbar by retaining member.

According to a third technical aspect of the present invention, drawing high-tension busbar easily can be avoided when interfering, the crooked durability of high-tension busbar can be more positively improved with vehicle frame.

Claims

1. the two-wheeled forcedly air-cooled engine of using, its engine body (34) makes its cylinder-bore axis (C) approximate horizontal, and spark plug (51) is installed in cylinder head (37) at least one side, the left and right sides as the part of constituting component, this engine body (34) can be bearing on the vehicle frame (25) with fluctuating, cylinder head at least (37) in the above-mentioned engine body (34) is covered with by guard shield (82), this guard shield (82) will be used to make the circulation flow path (81) of the air ventilation that forced air cooling uses to be formed between itself and the above-mentioned cylinder head (37), it is characterized in that, framework member (29 after the pairing left and right that above-mentioned vehicle frame (25) is had, 30) side's upper support spark coil (126), this spark coil (126) is configured in the rear of above-mentioned cylinder head (37), is connected on this spark plug cap (121) after rearward roughly turning back from the place ahead that is connected the spark plug cap (121) on the above-mentioned spark plug (51) in the other end that an end is connected the high-tension busbar (123) on this spark coil (126) U word shape.

2. the two-wheeled forcedly air-cooled engine of using as claimed in claim 1, it is characterized in that, above-mentioned guard shield (82) has a pair of top and the lower cover parts (83 up and down that the above-mentioned cylinder head of common covering mutually combines (37), 84), the embedding hole (120) that is used for chimeric above-mentioned spark plug cap (121) is formed on above-mentioned two cap assemblies (83, between mating face 84) (86), on upper cap member (83), be provided with integratedly and cover the penthouse (122) of above-mentioned spark plug cap (121) from the top to the chimeric embedding part of above-mentioned embedding hole (120), being applied the above-mentioned spark plug cap (121) of bias voltage from the elastic force of above-mentioned high-tension busbar (123) effect to the side around the axis of above-mentioned spark plug (51) contacts combination with spline positioning part (122a) on being formed on above-mentioned penthouse (122), and this spline positioning part (122a) is resisted above-mentioned resilient support and lived spark plug cap (121).

3. the two-wheeled forcedly air-cooled engine of using as claimed in claim 2, it is characterized in that, keep the retaining member (124) of above-mentioned high-tension busbar (123) to be installed on the retaining member fitting seat (125), this retaining member fitting seat (125) is formed on the above-mentioned upper cap parts (83) continuously with above-mentioned penthouse (122).