CN1306149C

CN1306149C - Rocker arm positioning structure

Info

Publication number: CN1306149C
Application number: CNB2004100396734A
Authority: CN
Inventors: 久保田良; 菊池一纪
Original assignee: Honda Motor Co Ltd
Current assignee: Honda Motor Co Ltd
Priority date: 2003-03-17
Filing date: 2004-03-16
Publication date: 2007-03-21
Anticipated expiration: 2024-03-16
Also published as: JP4111850B2; JP2004278435A; CN1530522A

Abstract

In the valve system of the internal combustion engine, the rotation of intake/exhaust cams is respectively transmitted to intake/exhaust valves through the rocker arm 28, and the intake/exhaust valves are respectively opened and closed at predetermined timings. The rocker arm 28 is swingably attached to a rocker arm shaft 26 while providing a space in the axial direction, and a collar 27 is inserted in the space. The collar 27 is C-shaped in cross section having a cutting slit along the rocker arm shaft 26.

Description

The rocking arm position structure

Technical field

The present invention relates to the rocking arm position structure in the valve actuating gear of internal-combustion engine.

Background technique

Rocking arm position structure in the valve actuating gear of internal-combustion engine of the prior art is, in rocking arm one side of the free shaking bearing of break-through cylinder head a portion is set, and this one inserts elasticity tube, and this elasticity tube is inserted between the end face of rocking arm and cylinder head with flexibility.(for example, with reference to Patent Document 1)

(Patent Document 1) opens clear 54-161412 communique in fact

Summary of the invention

In described rocking arm position structure of the prior art, rocking arm can not move axially, so with the valve tappet gap of pad adjustment suction, exhaust valve the time, must take out pitman arm shaft rocking arm is pulled down from cylinder head for changing pad.In addition,, inertial mass is increased, the end face of rocking arm is compressed into cylinder head, slip resistance is increased because rocking arm shakes with the elasticity tube.

For solving described the problems of the prior art, first aspect present invention, be the rotation of suction, exhaust cam to be passed to suction, exhaust valve by each rocking arm, this suction, exhaust valve are carried out in the valve actuating gear of internal-combustion engine of on-off action constantly in regulation respectively, can freely shake described rocking arm and to be installed on the pitman arm shaft and when being axially arranged with the space, insert axle sleeve in described space, described axle sleeve is formed from a resin and section is the C word shape that has along the otch seam of described pitman arm shaft.

A first aspect of the present invention can freely be shaken by said structure because described rocking arm and is installed on the pitman arm shaft and when being axially arranged with the space, inserting axle sleeve in described space can be in the inertial mass that does not increase rocking arm, stop moving axially of rocking arm when not increasing slip resistance, thereby reduce the friction of valve system, improve SFC.In addition, by axle sleeve is made elastic material, can suppress the impact sound that moving axially of rocking arm sent.

By the opening portion (otch seam) of opening the c-shaped section of axle sleeve, the easily relative pitman arm shaft of axle sleeve is pulled down loaded onto.Therefore, when adjusting, need not from cylinder liner, take out rocking arm and pitman arm shaft in the valve tappet gap of gasket type, after axle sleeve is taken off from pitman arm shaft, as long as rocking arm axial direction on pitman arm shaft is moved, just can change pad, therefore can significantly improve operating efficiency.

Second aspect present invention, on described first aspect basis, described internal-combustion engine is set up in parallel two pitman arm shafts, is respectively equipped with axle sleeve on described pitman arm shaft, has flange (27a) in an end of described axle sleeve, this flange (27a) and rocking arm ground connection configuration mutually.

Description of drawings

Fig. 1 is the internal-combustion engine that the is applicable to one embodiment of the invention sectional arrangement drawing of roughly cutting open by the plane of crankshaft center line and cylinder-bore axis;

Fig. 2 is the sectional arrangement drawing of equally roughly cutting open by the cylinder-bore axis plane vertical with cylinder-bore axis;

Fig. 3 is used in the sectional arrangement drawing that near the plane vertical with crankshaft center line of cam chain cut open equally;

Fig. 4 is the figure that amplifies presentation graphs 1 top;

Fig. 5 pulls down valve mechanism cover is seen cylinder head from above figure;

Fig. 6 is the sectional drawing of the VI-VI arrow of Fig. 5 and Fig. 7;

Fig. 7 is the sectional drawing of the VII-VII arrow of Fig. 4 and Fig. 6;

Fig. 8 is the figure of the axle sleeve 27 that takes off in from Fig. 5 to Fig. 7, and wherein figure (a) is that planimetric map, figure (b) are that front elevation, figure (c) are that following figure, figure (d) are D-D arrow sectional drawings;

Fig. 9 pulls down axle sleeve 27 from state shown in Figure 7, from the figure of the position deviation state of rocking arm 28.

Embodiment

Fig. 1 is the internal-combustion engine that the is applicable to one embodiment of the invention sectional arrangement drawing of roughly cutting open by the plane of crankshaft center line and cylinder-bore axis; Fig. 2 is same with the sectional arrangement drawing of roughly cutting open by the cylinder-bore axis plane vertical with cylinder-bore axis; Fig. 3 is used in the sectional arrangement drawing that near the plane vertical with crankshaft center line of cam chain cut open equally; Fig. 4 is the figure that amplifies presentation graphs 1 top; Fig. 5 pulls down valve mechanism cover is seen cylinder head from above figure; Fig. 6 is the sectional drawing of the VI-VI arrow of Fig. 5 and Fig. 7; Fig. 7 is the sectional drawing of the VII-VII arrow of Fig. 4 and Fig. 6; Fig. 8 is the figure of the axle sleeve 27 that takes off in from Fig. 5 to Fig. 7, and wherein figure (a) is that planimetric map, figure (b) are that front elevation, figure (c) are that following figure, figure (d) are D-D arrow sectional drawings.

This internal-combustion engine 1 is an Overhead valve four-cycle, single-cylinder internal-combustion engine.Its body such as Fig. 1 are made up of crankcase 2a, 2b about being divided into, cylinder block 3, cylinder head 4, valve mechanism cover 5, left crankcase cover 6a, right crankcase cover 6b to shown in Figure 3.Left crankcase 2a and right crankcase 2b are involutory mutually, place cylinder block 3, cylinder head 4 and valve mechanism cover 5 above it successively.In addition, at the left surface fastening left crankcase cover 6a of left crankcase 2a, at the right flank fastening right crankcase cover 6b of right crankcase 2b.In addition, crankcase 2a, the 2b about these, cylinder block 3, cylinder head 4, valve mechanism cover 5, left crankcase cover 6a, right crankcase cover 6b are fused mutually by bolt etc.

As shown in Figure 1 and Figure 2, piston 8 is inlaid in the cylinder-bore 7 that is formed at cylinder block 3 with being free to slide, and the bent axle 9 rotatable earth's axis are propped up at left and right sides crankcase 2a, 2b simultaneously.On piston 8 and bent axle 9, turn the two ends that the earth's axis are being propped up connecting rod by means of wrist pin 10 and crankpin 11 respectively.Like this, the burning by the mixed gas in cylinder-bore 7 top combustion chamber 13 makes piston 8 to-and-fro motion, 9 rotations of driving bent axle.

The intakeport 14 and the relief opening 15 that are communicated with the top combustion chamber 13 of cylinder-bore 7 form in cylinder liner 4.But the air-breathing valve 16 and the exhaust valve 17 (with reference to Fig. 2) of freely openable are set respectively at these intakepories 14 and relief opening 15.The valve tappet gap of these air-breathing valves 16 and exhaust valve 17 is by the pad adjustment.

Camshaft 18 is adjacent with the top of air-breathing valve 16 and exhaust valve 17.One end of this camshaft 18 (left part of Fig. 1, Fig. 4) is clipped free to rotately by cylinder liner 4 and cam pedestal 20 by camshaft bearing 19a and is being propped up by axle, and the other end (right-hand member of Fig. 1, Fig. 4) props up on cylinder liner 4 by the camshaft bearing 19b earth's axis free to rotate.Place in turn in a described end of camshaft 18 by movable sprocket 21 and magnet frame 22 and by bolt 23 and be mounted to one.In addition, on bent axle 9, be wholely set driving sprocket wheel 24, at this driving sprocket wheel 24 and the described cam chain 25 that hangs annular on by movable sprocket 21.

As Fig. 2 and shown in Figure 6, disposing a pair of pitman arm shaft 26 respectively and make its axis in the top of air-breathing valve 16 and exhaust valve 17 and the centre above the camshaft 18 is level, any one of two ends and cylinder liner 4 and cam pedestal 20 chimeric (with reference to Fig. 5, Fig. 7).On these a pair of pitman arm shafts 26, can freely shake the earth's axis respectively and prop up rocking arm 28.Propping up roller 29 and touch with the nose of cam 18a of described camshaft 18 at an end axle of this rocking arm 28, the other end touches with the top of air-breathing valve 16, exhaust valve 17 respectively.Like this, when internal-combustion engine 1 operation, rotate with half rotating speed drive cam shaft 18 of bent axle 9, air-breathing valve 16 and exhaust valve 17 whenever take two turns at bent axle 9, are driven switching respectively once.

As mentioned above, can freely shake the earth's axis at pitman arm shaft 26 and prop up rocking arm 28, this rocking arm 28 is as Fig. 5 and shown in Figure 7, space mounting axially is being set, insert axle sleeve 27 in this space, this axle sleeve 27 is resin manufacture, and shape as shown in Figure 8, at one end have flange 27a, its section is the C font that has with the breach of parallel axes seam 27b.

Symbol 40 expression among Fig. 4, Fig. 5, Fig. 7 and Fig. 9 is used to positioning plate that pitman arm shaft 26 is stopped operating, and the 42nd, be used for fixing the elastic member of positioning plate 40.

Then, as shown in Figure 1 and Figure 4, the described magnet frame 22 of installing in an end (left end of the figure) one of camshaft 18 forms the cylindric of minor diameter in the place of the internal side diameter that is positioned at passive sprocket wheel 21, and large diameter cylindric in its outside formation.Stride across circumferencial direction and a plurality of permanent magnets 35 uniformly-spaced are set integratedly at the inner peripheral surface of its large diameter cylindric portion.

In addition, in the outside of camshaft 18 (left of Fig. 1 and Fig. 4) cooling waterpump 30 is set.The pump cover 31 of this cooling waterpump 30 is chimeric to be fixed on the opening of the sidewall that is formed at cylinder head 4, at the cardinal extremity of these pump cover 31 tight chimeric pump housings 32.There is certain interval in cylindric the large diameter cylindric portion with magnet frame 22 of this pump housing 32.In addition, configuration pump shaft 33 on the rotation axis of camshaft 18, its two ends are chimeric with the pump cover 31 and the pump housing 32 free to rotately.Turn 34 these pump shaft 33 chimeric installing back, position one mounting permanent magnet 36 in the cylindric portion of this solid of rotation 34 at the permanent magnet of installing with described magnet frame 22 one relatively 35.Be positioned at the integrally formed blade 37 in outside (left of Fig. 4) of the cylindric portion of solid of rotation 34.Like this, when being driven rotation by movable sprocket 21, the magnet frame that becomes one therewith 22 is rotated, and the permanent magnet 36 that is integral installation with the solid of rotation 34 of cooling waterpump 30 rotates by means of the magnetic force with the permanent magnet 35 of magnet frame 22 rotations, rotates thereby drive cooling waterpump 30.

In this internal-combustion engine 1, light the fuel-air mixture of supplying with firing chamber 13, fuel detonation pushes piston 8.By making air-breathing valve 16 and exhaust valve 17 actions send exhaust and igniting repeatedly, make reciprocating motion of the pistons in the order and the moment of regulation.This of piston 8 moves through connecting rod 12 rotates bent axle 9, passes to not shown wheel etc. again.The rotation of bent axle 9 is also by driving sprocket wheel 24, cam chain 25, passed to camshaft 18 by movable sprocket 21, further by nose of cam 18a and rocking arm 28 with the order of regulation with open and close described air-breathing valve 16 and exhaust valve 17 constantly.

When exchange is used to adjust the pad in gap of described air-breathing valve 16 and exhaust valve 17, from pitman arm shaft 26 axle sleeve 27 is pulled down as shown in Figure 9.Owing to the breach that is provided with at axle sleeve 27 with parallel axes stitches 27b, so by opening this otch seam 27b dismounting pitman arm shaft 26 at an easy rate.Then as shown in the figure, rocking arm 28 is moved axially on pitman arm shaft 26, exchange the pad of the top 16a of air-breathing valve 16 or exhaust valve 17.

At present embodiment, when carrying out spacer chip valve tappet gap, rocking arm 28 and pitman arm shaft 26 are not pulled down from cylinder liner 4, after axle sleeve 27 is pulled down from pitman arm shaft 26, only lean against and move axially rocking arm 28 on the pitman arm shaft 26 and just can change pad, therefore greatly improved operating efficiency.

In addition,, do not increase the inertial mass of rocking arm 28, do not increase slip resistance yet, and can stop rocking arm 28 to move axially, thereby can reduce the friction of valve driving system, improve SFC at present embodiment.In addition, by axle sleeve 27 is made elastomer-forming, can suppress the impact sound that rocking arm 28 sends when moving axially.

Claims

1, a kind of rocking arm position structure is characterized in that, by each rocking arm inhale, the rotation of exhaust cam passing to suction, exhaust valve, and this suction, exhaust valve are carried out in the valve actuating gear of internal-combustion engine of on-off action constantly in regulation respectively,

Can freely shake described rocking arm and to be installed on the pitman arm shaft and when being axially arranged with the space, insert axle sleeve in described space,

Described axle sleeve resin is made and section is the C word shape that has along the otch seam of described pitman arm shaft.

2, rocking arm position structure as claimed in claim 1, it is characterized in that described internal-combustion engine is set up in parallel two pitman arm shafts, is respectively equipped with axle sleeve on described pitman arm shaft, has flange (27a) in an end of described axle sleeve, this flange (27a) and rocking arm ground connection configuration mutually.