CN2685574Y - Ejector pin type distribution mechanism for engine - Google Patents

Abstract

The utility model relates to an ejector pin type distribution mechanism for engine. The cam of the cam shaft of the engine connects with a lower swinging arm which connects with an ejector pin, and the ejector pin connects with an upper swinging arm which connects with a value. The upper swinging arm is equipped with the valve spring of the upper swinging arm. The ejector pin type distribution mechanism for engine is characterized in that the ejector pin type distribution mechanism for engine has a torsion spring of a pair hanging hooks, and the torsion spring ring of the torsion spring is covered on the swinging arm shaft between two lower swinging arms or the hub of the swinging arm. The two hanging hooks respectively hang a lower swinging arm. Because the ejector pin type distribution mechanism for engine eliminates the clearance between the ejector pin and the upper and lower swinging arm, and thoroughly eliminates the knock and the abrade produced by the prior clearance. So the utility model thoroughly eliminates the noise produced by the knock as well as greatly extends the maintenance period and the service life of the distribution mechanism and even the engine.

Description

The post rod type distribution device of motor

One, technical field

The utility model relates to the distribution device of motor, especially the distribution device of post rod type.

Two, background technique

In various mini engines, a kind of motor that is called as " CG machine " or " push rod machine " at motorcycle industry is arranged.Because it has adopted the structure of overhead valve and lower arranging cam axle, so its power performance is good, reliability is high, and price is also cheap relatively.In the city or the rural area all be subjected to welcome.Yet, but the feature of this overhead valve and lower arranging cam axle has been brought negative problem.Because the distribution device that this structure characteristic has determined it has been Duoed one group of rocking arm than general engine valve actuating mechanism, promptly this distribution device has two groups of rocking arms up and down---claim that in motorcycle industry this distribution device is the OHV distribution device.The lower shake-changing arm of this distribution device is driven by the cam on the camshaft, and this lower shake-changing arm drives push rod, and this push rod drives upper rocker arm again, controls opening and closing of valve by this upper rocker arm and upper rocker arm Returnning spring at last.On the one hand, for " interference " do not take place, between the lower shake-changing arm and push rod in the existing this distribution device, certain clearance (having Duoed the gap of this character in a place than the distribution device of other classes) all arranged between push rod and the upper rocker arm.Because the existence in this class gap must just have bump when work, have bump again wearing and tearing must be arranged; And this wearing and tearing make that described gap increases and are that gap, two places all will increase, and certainly, clash into just more terriblely again ..., so vicious circle.On the other hand, for reliable operation, be Spielpassung between the pitman arm shaft of last lower shake-changing arm and the rocker shaft hole that it matches.Because wearing and tearing, after work a period of time, these gaps all can increase.And the increase in these gaps can " be transmitted " between lower shake-changing arm and the push rod, between pre-bar and the upper rocker arm, finally further aggravated the bump between them again.So this motor is in when operation, not only the Strike note that sends of machine is very big, and the cycle of maintenance, repair is also very short.

Three, summary of the invention

The purpose of this utility model is designed the distribution device that can reduce the bump between its upper and lower rocking arm and the push rod greatly for overcoming above-mentioned shortcoming.

Realize the post rod type distribution device of a kind of motor of described purpose, the cam of engine cam is connected with lower shake-changing arm, lower shake-changing arm is connected with push rod, push rod is connected with upper rocker arm, upper rocker arm is connected with valve, the upper rocker arm valve spring is installed on the upper rocker arm, it is characterized in that: the torsion spring that a pair of hook is arranged, the torsion spring ring set of this torsion spring is on pitman arm shaft between two lower shake-changing arms or rocking arm hub, two each hook of hook are lived a lower shake-changing arm, and the action direction of its elastic force is to allow lower shake-changing arm be close to the direction of the push rod of its driving.That is to say that this elastic force forces this lower shake-changing arm to be close to the push rod that is driven by it.Obviously, by transmitting, the other end of described push rod is close to described upper rocker arm again.

Further scheme is that described torsion spring can also be extension spring, stage clip, flat spring etc., as long as enough mounting points are arranged and guarantee that described lower shake-changing arm can be close on the described push rod reliably.

The superiority that the technical program is taken to is as follows:

From background technique and scheme, be not difficult to find out, because the effect of torsion spring elastic force, make and all be close between the last lower shake-changing arm at described push rod and its two ends, eliminated gap everywhere.Simultaneously, also eliminated because of the wearing and tearing between pitman arm shaft and rocker shaft hole and increased also the gap that " transmission " comes.Certainly, just thoroughly eliminated the bump that brings by original these gaps.Like this, both thoroughly eliminate the noise that this bump produces, prolonged the maintenance period and the working life of this distribution device and even motor again widely.

For avoiding aforesaid " interference ", the gap is after eliminate at above-mentioned position, and it has just been transferred between the cam of described lower shake-changing arm and driving lower shake-changing arm.Described bump is also transferred to here.But, to compare with the quantity and the area size of existing impact site, bump quantity of the present utility model has reduced half, the area of contact at bump place much bigger again (impact force that is unit area is much smaller).So minimum at the Strike note at this place, the wearing and tearing that the bump back produces are also very little.And this transfer is to also have favourable one side, and promptly its position that can allow cam and lower shake-changing arm be contacted with cam obtains well lubricatedly, makes the surface of cam that enough thick oil film be arranged.Equally also prolonged the working life of motor.

Four, description of drawings

Fig. 1---the utility model structural representation

Fig. 2---be the partial enlarged drawing at center with the torsion spring among Fig. 1

Five, embodiment

A kind of post rod type distribution device of motor, the push rod 3 that it includes lower shake-changing arm 2 that the cam 1 of launched machine camshaft driven, driven by this lower shake-changing arm 2, the upper rocker arm 5 that is driven by this push rod 3 and by this upper rocker arm 5 and upper rocker arm valve spring 6 its valves of opening and closing 4 of control thereof.Act on the described lower shake-changing arm 2 by it as elastic device with spring, be close to the push rod 3 that is driven by it to force this lower shake-changing arm 2, an end and the described lower shake-changing arm 2 of promptly described push rod 3 are close to.Be close to described upper rocker arm 5 again by the other end that transmits described push rod 3.Consider that from manufacture cost and angle easy for installation the torsion spring 7 of the described employing of this example more particularly is the torsion spring 7 of two hooks.During assembling, on the pitman arm shaft or rocking arm hub of 2 of two lower shake-changing arms, two each hook of hook are lived a lower shake-changing arm 2 with the torsion spring ring set of this torsion spring 7, and the action direction of its elastic force is to allow lower shake-changing arm 2 be close to the direction of the push rod 3 of its driving.Obviously, the concrete installation method of torsion spring 7 is not limited to this, and the installation method of any routine all is feasible.

Remind especially, as long as the described elastic force that acts on the torsion spring 7 of lower shake-changing arm 2 can guarantee to eliminate described gap reliably; Definitely can not be greater than the elastic force of upper rocker arm Returnning spring 6, otherwise valve 4 just can not have been closed reliably.

Claims (1)

1, a kind of post rod type distribution device of motor, the cam of engine cam (1) is connected with lower shake-changing arm (2), lower shake-changing arm (2) is connected with push rod (3), push rod (3) is connected with upper rocker arm (5), upper rocker arm (5) is connected with valve (4), on broadcast upper rocker arm valve spring (6) be installed on the arm (5), it is characterized in that: the torsion spring (7) that a pair of hook is arranged, the torsion spring ring set of this torsion spring (7) is on the pitman arm shaft or rocking arm hub between two lower shake-changing arms (2), and two each hook of hook are lived a lower shake-changing arm (2).