CN1251637A - Adjustment mechanism for valve - Google Patents

Abstract

A device for adjusting the movement characteristics of an engine valve, including a regulator capable of changing the opening and closing angle of the valve and changing the lift of the valve, the device including a guide movable from a first position to a second position The guide element has a guide path for receiving the guide member of the valve drive mechanism, and the movement trajectory of the guide member in the guide path when the regulator is in the first position is different from the movement trajectory of the guide member when the regulator is in the second position of.

Description

valve adjustment device

technical field

The present invention relates to the improvement of the engine (such as internal combustion engine), in particular to the improvement of the movement mechanism of the internal combustion engine valve (especially mushroom valve).

The invention is also applicable to other engines and pumps using valve mechanisms.

technical background

The available torque of an internal combustion engine is primarily determined by the volumetric efficiency of the engine. For a reciprocating piston engine, this efficiency is a measure of the volume of air that the engine draws into the cylinder during the intake stroke relative to the cylinder's scavenging volume.

The valve timing of a reciprocating internal combustion engine has a significant effect on the volumetric efficiency of the engine at certain engine speeds. The engine has a fixed valve timing, that is, the valve opens at a fixed crank angle before the top dead center of the piston, and closes at a fixed crank angle after the top dead center. The engine can only work at a certain speed to achieve the highest performance. efficiency. At this speed, the positions of the intake and exhaust valves relative to the piston are fixed and synchronized, and the mutual cooperation can generate the maximum torque.

Obviously, it would be ideal if maximum torque could be given over a wide engine speed range. In order to achieve maximum torque at high engine speeds, the ideal condition is that the intake and exhaust valves should be open for the largest possible range of piston travel, because this allows more time for air to enter the cylinder and exhaust gas. Exhaust cylinders to increase the volumetric efficiency of the engine. However, there are several limiting factors in how far the piston travels or how far the intake and exhaust valves can remain open (or crank angle). For example, in order to increase the opening angle of the valve, the opening angle of the intake and exhaust valves will be increased at the same time, the so-called valve overlap, which is beneficial at high engine speed because it can increase the torque output. However, the same amount of valve overlap that produces good torque at high engine speeds can result in poor engine operation and reduced torque output at low speeds. Thus, in general, early valve opening and late closing increases volumetric efficiency at high speeds at the expense of low speed torque. Conversely, reducing the valve overlap will increase the engine's low-speed torque but will not yield the best high-speed volumetric efficiency.

Therefore, ideally, such a mechanism should be designed so that the opening and closing timing of the valve can be adjusted according to the operating parameters such as the engine speed, so that the best torque can be obtained in a wide range of engine speed. In addition, other parameters of the engine, such as throttle valve position, gear meshing conditions, etc., can also be used to change the timing of valve opening and closing.

In addition to valve timing, there are other factors that have a significant impact on the operation of mushroom valves in reciprocating engines. Firstly, just before the valve is about to open, the valve driver is slowly accelerated towards the valve in order to reduce and eventually eliminate the play between the valve and the driver or between the intermediate tappet and the driver. This ensures that the valve and actuator do not collide with each other with great speed and impact. After that, the valve needs to be opened as quickly as possible to allow fresh air and fuel to enter the cylinder smoothly from the intake valve, or to discharge the exhaust gas in the cylinder from the exhaust valve. Once a valve is opened, it should remain open for as long as possible before it is quickly closed. The valve should then seat as gently as possible and remain open and closed until the next cycle is restarted. Since there should be no appreciable change in valve motion (such as excessive acceleration) at this point, it is noted that a generally sinusoidal motion in the valve motion trajectory is acceptable.

The actuation of valves and the control of their movement have traditionally been achieved by using camshafts. There are eccentric cam lobes on the camshaft which will push the valves, where the profile of the cam lobes determines the kinematic characteristics of the valves. The problem with this structure is that when the camshaft rotates rapidly, the valve is kept in contact with the outer surface of the cam lobe by the valve spring, but when the camshaft rotates faster, the valve may leave the cam lobe due to inertia. The outer surface. Although this problem can be partially solved by increasing the strength of the valve spring, this will make the valve opening difficult and the wear of the cam lobe surface will be accelerated.

Another major problem with camshafts is the inability to change the profile shape of the cam lobes, so changing the kinematic characteristics of the valves is very difficult. To change the valve timing, the camshaft needs to be replaced or machined, so that the optimum torque characteristics can only be obtained within a narrow range of engine speeds for a particular cam lobe profile. This is one of the reasons why the engine runs well at high revs but lacks torque in the lower rev range. In addition, since the valve spring always presses the valve tightly against the cam lobe when the camshaft rotates, a large torsional force is generated along the length of the camshaft, which may damage the camshaft.

While there have been attempts to solve the above problems using a number of existing arrangements, none have been entirely satisfactory. One arrangement has two standard lobes for the intake valves on one camshaft and a third cam lobe between the two standard intake lobes. When the engine is running below a certain speed, the two intake valves are actuated by standard cam lobes, and when the engine accelerates above a predetermined speed, a pin engages the valve driver, so that the two valves are driven by the third valve. The cam lobe is driven, and the cam lobe has a unique external profile suitable for high speed, which can make the intake valve open early and keep it open for a long time. A similar mechanism can also be used for the exhaust valve camshaft. A disadvantage of this system is that it does not allow the timing of valve opening and closing to vary between two predetermined valve motion characteristics, ie only two valve opening durations are possible. This makes the torque output of the engine change in a "step" shape from low speed to high speed, and cannot achieve the maximum torque output in the entire engine speed range, but only achieves the best at two certain speeds.

Another way to vary the valve opening and closing angles is to have the cam speed not always equal to half the crankshaft speed for some portion of a single speed, but to vary with engine speed. For example, the camshaft rotates at a nominal speed of half the crankshaft speed at low speeds. At high speeds, a mechanism mounted on the camshaft rotates the camshaft at less than half the speed of the crankshaft, simultaneously opening the valves and keeping them open, allowing the valves to open at a wider angle than at low speeds . To make up for lost time (because the camshaft must equalize one revolution for every two revolutions of the crankshaft), the camshaft must rotate at more than half the speed of the crankshaft during the remainder of the rotation to ensure that the valve is in the correct position when it reopens. position. Obviously, this system is also not ideal, and it uses a set of complex mechanisms to change the rotational speed of the camshaft within one revolution of the crankshaft. In addition, since the profile shape of the cam lobe cannot be changed, it is impossible to change the valve lift.

Another disadvantage of most valve actuators is that they include camshafts for opening the valves, which are not only difficult to manufacture but also prone to wear and damage.

There are also drawbacks to the method of adjusting the clearance between the top of the throttle valve and the valve actuator (rocker arm or camshaft lobes). Since it is necessary to add a clearance adjuster to the rocker arm, the inertia of the rocker arm will increase; if the shim adjustment is used, it will not only be difficult to place the shim under the cam lobe, but also need to increase the shim positioning element, which will cause This increases the length of the valve assembly resulting in an increase in engine size.

Introduction to the invention

The object of the present invention is to overcome at least one of the disadvantages associated with the prior art.

To this end, the present invention provides a device for adjusting the kinematic characteristics of the valve. The kinematic characteristics of the valve include timing, such as the crank angle position of the crankshaft at the reference angle at which the valve begins before top dead center, the opening duration, such as the crank angle corresponding to the valve remaining open, lift or stroke at a certain crank angle position, speed and Stress condition. In one form, the adjustment is a mechanical manipulation. In another form, the regulator is located between the valve actuator and the valve. An advantage of adjusting the throttle motion characteristics in accordance with the method of the present invention is that the desired engine performance criteria can be selected from a number of predetermined characteristics, and the angle at which such criteria can be achieved. For example, adjustments to valve movement characteristics may be selected to increase engine output torque, or may be selected to increase engine fuel economy.

It is also possible to produce a valve drive which produces an approximately sinusoidal valve lift movement with respect to the crankshaft angle and enables a change in the movement characteristics of the valve.

Typically, valve actuation mechanisms include a rotating element.

In general, the regulator can change the opening angle of the valve and/or the closing angle of the valve and/or the valve lift, individually or in combination. It can be seen that it is advantageous to vary the lift and opening duration of the valve. Although these two items can also be done separately, it has been found that increasing the valve lift and opening duration is more effective as the engine speed increases.

Obviously, it is desirable if the regulator can change the opening and closing angle of the valve and the valve lift together in a coordinated manner.

In another form, the present invention provides apparatus for adjusting the movement of a flow valve including an adjuster that moves along a non-linear path to adjust movement of the flow valve.

In another form, the present invention provides an adjustment device for use in an apparatus for adjusting the kinematics of a throttle valve comprising a plate having a guide path.

In another form, the present invention provides an apparatus for adjusting the kinematic characteristics of a flow valve comprising a first guide path and a second guide path, wherein the kinematic characteristics of the valve are determined by the difference in shape between the first and second guide paths and alignment difference to decide.

In another form, the present invention provides apparatus for adjusting flow valve clearances performed by a mechanically controlled valve actuator comprising a threaded end valve.

In a preferred embodiment, the device for adjusting the kinematic characteristics of the throttle valve comprises an adjusting element with a guide path and a rotatably mounted valve actuating element with at least one guide surface, wherein a pin follows the guide path and guide surface, thereby pivoting the rotatably mounted drive element and driving the valve.

Generally, the driving is basically performed in a cyclic motion.

Ideally, the guide path of the adjusting element and the guide surface of the valve drive element are not parallel and juxtaposed over their entire length, ie their paths are different and deviate from each other at least over part of their length. This path difference creates motion for the drive element as the pin moves along the two paths. Also, a dynamic switching of pins and guides is considered as another embodiment. preferred embodiment

Several embodiments of the invention will now be described with reference to the accompanying drawings, which are:

Figures 1a-1d are schematic diagrams representing the regulator of the present invention in different assembled states;

Fig. 2 a is the lateral schematic view of the regulator of the present invention and the valve driving mechanism of the prior art;

Figure 2b is a schematic diagram of the non-mechanical control valve regulator of the present invention and the valve drive mechanism of the prior art;

Figure 3 is a partial isometric view of a first embodiment of the regulator of the present invention;

Figure 4 is a full isometric view of the first embodiment of the regulator of the present invention;

Figures 5a and 5b are side views of a second embodiment of the regulator of the present invention;

Figures 6a and 6b are side views of the regulator shown in Figures 5a and 5b;

Fig. 7 is a limit change curve diagram of the valve lift and opening duration of the regulator of the present invention relative to the crank angle;

Figure 8 shows a first example of the adjuster guide plate of the present invention;

Fig. 9 shows the second example of the adjuster guide plate of the present invention;

Fig. 10a-10d is the example diagram of the rocker arm of adjuster of the present invention;

Fig. 11 is a schematic side view of the first example of the path on the regulator guide plate of the present invention;

Fig. 12 is a lateral schematic view of the outline surface of the guide plate of the regulator of the present invention;

Fig. 13 is a side schematic view of a second example of the path on the regulator guide plate of the present invention;

Fig. 14 is a schematic diagram of the path on the regulator guide plate of the present invention;

Figures 15a-15d are some examples of the sliding pin of the regulator of the present invention;

Figures 16a-16d are some examples of the regulator guide plate of the present invention;

Fig. 17a is the first example of the adjuster guide plate adjuster of the present invention;

Fig. 17b is the second example of the guide plate adjuster of the adjusting device of the present invention;

Figure 18a is a perspective view of the valve gap adjustment mechanism of the present invention;

Figure 18b is an exploded perspective view of the valve clearance adjustment mechanism shown in Figure 18a.

Referring to Figures 2a, 2b, 4, 5a and 5b, the mechanism 10 shown in the figures is used to adjust the kinematic characteristics of the mushroom valve 1. Mechanism 10 includes a drive means such as a valve drive crankshaft 12 having a crank pin 13 for providing cyclic displacement motion and substantial drive timing to valve 1 . The valve crankshaft 12 is usually driven by known devices such as a crankshaft (not shown) by a belt, a chain or a gear drive, and its rotating speed is half of the engine crankshaft rotating speed. The mechanism 10 is generally installed at the front of a reciprocating four-stroke engine (not shown), and it also includes a pivot shaft 14 fixed at the front for rotatably positioning a rocker 16 that drives the valve 1 . A guide member such as a guide plate 18 is installed on the cylinder head and can move within a certain range of positions, such as moving from a first position 20 to a second position 22, as shown in FIGS. 1b, 5a, 5b, 6a, 6b and 9 .

The crank pin 13 is connected through a hole 15 to one end of a connecting rod 24 which has a slide pin 26 at the other end, as shown in FIGS. 1a-1d, 2 and 3 . As the valve crankshaft 12 rotates, the connecting rod 24 moves the slide pin 26 along the path 25 on the guide plate 18 . The guide plate 18 does not follow the movement of the slide pin 26 , which is constrained to move within the path 25 and also moves along the path 28 on the rocker arm 16 . Usually each valve 1 has a rocker arm 16, if each cylinder has two intake valves (or exhaust valves) then there should be two rocker arms 16. Two rocker arms 16 and guide plate 18 can share a connecting rod 24 and slide pin 26 shown in Figure 4, when there are 4 valves in each cylinder engine cylinder head, it can drive two valves simultaneously exhaust). Obviously, the number of valves that each connecting rod and/or sliding pin can actuate is not limited to two intake/exhaust valves per cylinder. In the case of a mechanically controlled valve actuation, the path 28 may take the form of a path with upper and lower contoured surfaces as shown in Figures 1a, 1b, 2a, 4, 5a, 5b, 6a, 6b, 10a, 10c, 13 and 14 , or in the case of a conventional valve actuation with a spring providing the valve closing force, there may also be only one contoured surface, as shown in Figures 2b, 10b and 10d.

In both valve actuation methods described above, the path 25 in the guide plate 18 constrains the movement of the slide pin 26 within the path outlined by the path 25 , thereby causing the rocker arm 16 to rotate about the pivot axis 14 . When the rocker arm 16 rotates, it is away from the fork-shaped drive arm 32 of the pivot shaft 14, which is pushed against the valve 1 by means of two nuts screwed on the valve stem, as shown in Figures 5, 18a and 18b and described later, so that The valve 1 is opened and closed according to the difference in the profile shapes of the paths 25 and 28 . It is the difference in path profile shown in Figures 13 and 14 that causes the rocker arm 16 to pivot. The contour shapes of the paths 28 and 25 can be changed according to different requirements on the valve movement characteristics, and the requirements on the valve movement characteristics are also different due to the different purposes of each engine. Accordingly, no attempt should be made to limit the profile shapes of the individual paths on the guide plate 18 and rocker arm 16 to the examples presented herein.

In addition, the valve 1 can be replaced by a valve system 100, as shown in Figures 2a and 2b, wherein the valve system 100 includes a known gasket and positioning sleeve structure that can be used to adjust the flow valve clearance and ensure that the valve is in contact with the valve when the valve is closed. The actuator 32 remains in contact with the valve spring 101. This valve system can be used for non-mechanically controlled or conventional valve actuation. The mechanism 10 can also simply replace the camshaft 102 as the drive device for the valve.

The assembly parts of the mechanism 10 can be seen in FIGS. 1 a to 1 d , where the connecting rod 24 is shown fitted to the valve crankshaft 12 via the crank pin 13 , and the guide plate 18 and rocker arm 16 are connected to the slide pin 26 . Figure 3 shows the adjustment mechanism partially assembled, from which the relationship between the assembled valve crankshaft 12, connecting rod 24, slide pin 26 and pivot shaft 14, generally in a fixed position, can be seen. The pivot 14 is rotatable and also includes an eccentric portion 11 in this embodiment. The assembled mechanism 10 is shown in FIG. 4 . Among them, two guide plates 18 can be slidably sleeved on the eccentric portion 11 of the rocker shaft 14, and two rocker arms 16 are rotatably sleeved on the pivot shaft 14, so that the mechanism 10 can drive two intake valves or two exhaust valves. gas valve. In this case, the guide plate is restrained by pins (not shown) installed in the guide rail 9 and can only slide in a straight line.

In operation, the valve crankshaft 12 rotates at half the engine crankshaft speed. One end of the connecting rod 24 is connected with the crank pin 13 on the valve crankshaft 12 , and the other end is connected with the sliding pin 26 . Slide pin 26 is positioned within path 25 of guide plate 18 . As the valve crankshaft 12 rotates, the slide pin 26 is constrained to move along the path 25 of the guide plate 18 . The guide plate 18 is movable from a first position 20 to a second position 22 and anywhere in between. The profile shape of the guide path 25 as shown in the figure determines the movement trajectory of the slide pin 26 . Slide pin 26 also slides along path 28 of rocker arm 16 , the difference in profile shape of path 28 from path 25 causing rocker arm 16 to swing back and forth about pivot 14 . The valve driver 32 is installed on the rocker arm 16 and moves together with the rocker arm 16. It contacts with the end of the valve 1, pushes the valve open and pulls the valve closed. When non-mechanical control valve drive is used, the valve 1 can be closed by the valve spring.

In the case of Figures 2a, 2b, 3 and 4, in a second example, the eccentric adjustment shaft 30, as shown in Figures 5a, 5b, 6a, 6b, 17a and 17b, can be changed by turning the rocker shaft 14 plate 18 position. The shaft 30 has an eccentric cam lobe 31 that can rotate in the opening 34, which can make the guide plate 18 from the first position (the valve movement characteristics at this time are shown in curves 40a and 40b in Figure 7, which is suitable for low engine speed) to the second position (the valve movement characteristic at this time is suitable for high engine speed, as shown by curves 42a and 42b in Fig. 7). The movement of the guide plate 18 can be seen from the comparison diagrams of the valve opening positions shown in Figures 5a and 5b. In FIG. 5 a , the adjustment shaft 30 and the flap 31 position the guide plate 18 in the first position 20 . In Figure 5b, the adjustment shaft 30 and flap 31 position the guide plate 18 in the second position 22 such that the large valve opening shown in Figure 5b is greater than the maximum valve position seen in Figure 5a. The operation of the shaft 30 and petals 31 in the opening 34 of the guide plate is shown in Figures 17a and 17b and will be described in more detail below.

The kinematic characteristics of the valve can be seen from Fig. 7, wherein curve 40a is the relationship curve between the valve lift (ordinate) of the intake valve 1 driven by the valve crankshaft 12 and the engine crank angle (abscissa) and the guide plate at this time 18 is in the first position 20 . The movement characteristic of the exhaust valve when the guide plate 18 is in the first position 20 is shown by the curve 40b. Curve 42a represents the kinematic behavior of an intake valve when the guide plate 18 is in the second position 22 . The movement characteristic of the exhaust valve when the guide plate 18 is in the second position 22 is shown by the curve 42b. It can be seen from FIG. 7 that when the guide plate 18 is moved from the first position 20 to the second position 22, there are significant differences between the valve lift, opening duration and degree of overlap.

The reason for this difference in motion characteristics is that when the guide plate 18 is in the first position 20, the profile of the path 28 is in such a position that the profile difference between the path 25 and the path 28 is the smallest, as shown in Figure 5a, 5b and 8, which will be discussed below. Since the pin 26 is less deflected, the valve lift is lower, and the position of the pin is shown as 26a in FIG. 8 .

When the guide plate 18 is in the first position 20, the opening amount of the valve is the smallest and spans the smallest angle. Therefore, it is usually used for low engine speeds. Excessive valve overlap is not advisable at low speeds, and it is advisable to increase the swirl. of. The second position 22 of the guide plate 18 is used to obtain greater valve opening overlap and higher valve lift, as shown by the position of pin 26b in FIG. 8 . Compared with the valve opening duration in Fig. 5a, Fig. 5b has a longer valve opening duration. This arrangement is suitable for high engine speed conditions where maximum gas flow is required. Figures 6a and 6b show the guide plate 18 in the first and second positions, respectively. In both cases the valve is fully closed, ie the valve is effectively closed regardless of the position of the guide plate 18, as shown by the equivalent position of the valve in Figures 6a and 6b. The difference between the position of the guide plate 18 is clearly seen by the fact that there is a gap between the pivot 14 and the guide plate 18 in Figure 6b but not in Figure 6a. The mechanism 10 allows the guide plate 18 to be positioned at any point between the first position 20 and the second position 22 so that the valve overlap and/or opening angle can be adjusted to any point within a predetermined range of valve motion characteristics . The advantage of this adjustment is that the opening angle and/or lift of the valve can be changed at any time according to the change of the engine operating conditions in order to obtain the maximum volumetric efficiency.

The difference between the profile shape of the path 25 in the guide plate 18 and the profile shape of the path 28 in the rocker arm 16 can be designed to provide the desired motion characteristics of the valve. For example, when the rocker arm 16 used has a straight path 28, the path 25 may consist of four segments as shown in FIG. 11, each segment having its own specific function. Section A is the portion where the valve will be closed when the slide pin 26 is in this section. When the pin 26 moves along the path 25 and reaches section B, which is a transition section, it will cause the pin 26 to start moving in an angled direction with the direction of movement of section A, thereby causing the driver 32 to move at a relatively slow speed with the valve ( or valve gasket) because there is usually a small gap between the top of the valve assembly and the driver. After the top of the valve was in contact with the driver, the slide pin 26 entered section C of the path 25, the gradient of this section increased sharply, and the driver pushed the valve away very quickly. When the valve opening reaches the maximum, the sliding pin 26 enters the D section, at this moment, the opening speed of the valve decreases, and the valve begins to decelerate. In the D section, the sliding pin 26 reaches the end of its stroke, and the valve crankshaft 12 starts to pull the sliding pin 26 back in the opposite direction of the D section, at this time the valve will close again.

Figure 12 shows section A-D of the profiled surface of the guide plate, which utilizes a spring to return the valve to the closed position, so there is no need for the lower half of the path. The paths 50 and 51 of FIGS. 11 and 12, respectively, of the slide pin travel paths are designed for use with a rocker arm having a substantially straight path 28.

If the path of the rocker arm is the same shape as the path of the guide plate, there will be no relative motion between the rocker arm and the guide plate, and the valve will not move. Therefore, in order to obtain the desired valve movement, it is provided that either the rocker arm or the guide plate has a different profile. Both the guide plate path and the rocker arm path can be designed into various contour shapes. As an example, the shape of deflector path 52 in FIG. 13 could be used as long as the shape of rocker path 53 is varied in the correct area to drive the rocker. In Figure 14 the paths 25 and 28 are overlapped to highlight the difference in their profile shape which enables the rocker arm to swing and actuate the valve.

The difference between the guide plate path and the rocker arm path, which is related to the valve lift, can be clearly seen from Figures 13 and 14. The deflector path 52 in FIG. 13 can be rotationally adjusted as shown in FIG. 9 . It can be seen that this structure can increase the difference between paths 52 and 53, so it can obtain a larger valve lift than the linear adjustment shown in FIG. 14 . Realizing the increased valve lift shown in Figure 13 does not require a fundamental increase in the path deviation, which is necessary for a straight-line adjustable guide plate, and its adjustment is shown in Figure 8. For any path shape, too large path shape deviation is not advisable, because it will lead to increased wear of the path profile surface, so that the valve motion characteristics will be changed.

An advantage of the present system is that it results in a more square top of the valve movement curve than that shown in FIG.

In order to overcome or reduce the wear between the path 28 and the slide pin 26 due to the high contact pressure, it has been found that the section of the slide pin sliding along the path 28 (ie, the wear section) can be made into a non-circular cross-section.

The abradable portion 60 shown in FIG. 15a has the upper and lower surfaces of the slide pin in direct contact with the straight path 28 . The profile shape of these surfaces can vary with the shape of the opposing surface of the path, for example, when the flat path 128 of the rocker arm 116 shown in Figure 10a is used, the wear surface 160 will also be straight, such as the wear surface 60. Alternatively, the abradable surface can be a curved surface with a common center of curvature, as shown in abradable surface 360 in FIG. 15c, which can mate with a similarly curved path 328 in FIG. 10c with the same radius of curvature. If a conventional or non-mechanically controlled valve actuation mechanism is used, the sliding pins need only a single wear surface 260 and 460 as shown in Figures 15c and 15d, since the valve springs ensure that they are continuous with the corresponding path surface 28 ground contact.

It should be noted that the examples shown in Figs. 10a-10d, 15a-15d and 16a-16d should be used in conjunction with each other. The rocker arm 116 has a path 128 as shown in Figure 10a which cooperates with a pivot pin 126 as shown in Figure 15a and a guide plate 118 with a path 125 as shown in Figure 16a. This arrangement creates an adjustment device for mechanically controlled valve actuation in which the guide plate 118 is linearly adjusted.

Similarly, rocker arm 216 (FIG. 10b) with path 228 cooperates with pivot pin 226 (FIG. 15b) and guide plate 218 (FIG. 16b) with path 225 to form a valved regulator for closing the valve, Wherein guide plate 218 is also linear adjustment.

A rocker arm 316 (Fig. 10c) with a curved path 328 cooperates with a pin 326 (Fig. 15c) and a guide plate 318 (Fig. 16c) with a path 325 to form a mechanically controlled valve actuated regulator, wherein the guide plate 318 is the rotation adjustment.

A rocker arm 416 (FIG. 10d) with a curved path 428 cooperates with a pivot pin 426 (FIG. 15d) and a guide plate 418 (FIG. 16d) with a path 425 to form a valved regulator for closing the valve, wherein the guide Plate 418 is also rotationally adjustable.

FIG. 17 a shows an example of the position adjuster of the guide plate 18 , wherein the adjustment shaft 30 is located in the opening 34 of the guide plate 18 . When the adjustment shaft 30 is rotated, the eccentric cam lobe 31 on the shaft pushes the guide plate 18 to move linearly, as shown in FIG. 8 . The distance that the guide plate 18 moves linearly is determined by the amount of rotation of the shaft 30 . This allows the guide plate 18 to be adjusted to any position between the first position 20 and the second position 22, including the two extreme positions.

In FIG. 17b, the shaft 30 is rotatably seated in the opening 134 of the guide plate 618 which is mounted for adjustably rotating about the point 135. In FIG. As the shaft 30 rotates, the eccentric flap 31 forces the guide plate 618 to move. Since the guide plate has been constrained to pivot, rotation of the shaft 30 moves the guide plate 618 . As before, the amount of rotation of the guide plate 618 can be controlled by rotation of the shaft 30 .

A control unit (not shown) can be used to control the rotation of the shaft 30 in each mechanism 10, which can position the guide plate in any position between the first position 20 and the second position 22. Such a control unit may be a simple means of turning a shaft to cause the valve to open, or any other suitable means of actuating the guide plate. These mechanisms are typically used to advance the ignition timing as engine speed increases. In this case the valve timing can be adjusted together with the spark timing or independently.

Another example of a guide plate 518 is shown in FIG. 9 . Wherein the guide plate 518 is installed on a rotatable pivot 535, so the kinematic characteristics of the regulating flow valve can be rotated to the two points represented by the dotted line and the arrow in the figure by the pivot 535 (the guide plate 518 is integrated with it) Any position between the two positions, rather than a straight line adjustment as indicated by the arrows in Figure 8.

It should also be noted that in any of the examples given, the guide plate is positioned at discrete points between the first position 20 and the second position 22, for example by means of a stepper motor. Therefore, the position of the guide plate can be changed stepwise according to different parameters, such as engine speed, engine speed change rate, throttle valve position and timing gear position, etc. Thus, a fuzzy logic table can be developed to position the deflectors at a series of optimal positions based on a set of predetermined parameters.

Figures 16a to 16d show some other different types of deflectors. Each guide plate will be mounted in such a manner that its position can be controlled so that the path position of the slide pin can also be controlled. In the non-mechanical control structure of Fig. 16b and 16d, there is no need to open the path into a groove shape, and the contour shape can adopt the contour 125 and 325, and the spring force acts on the valve in the traditional way to close the valve, so it is always There is pressure acting on the profile 125 or 325 and the underside of the respective rocker arm 118 or 328 . The advantage of adopting this structure is that a large amount of prior art and data can be utilized at present to close the valve with the valve spring, and at the same time, the rocking arm that reciprocates like this can also be made lighter.

An example of means for adjusting the position of the guide plate is shown in Figures 17a and 17b. FIG. 17a is about a method for adjusting the linear position of the guide plate by using the rotating shaft 30 in the opening 34 of the guide plate 18 . As the shaft 30 rotates, petals 31 on the shaft drive the guide plate into the desired position. The opening 34 is configured to allow the guide plate 18 to move linearly so that the side walls of the hole are generally rectilinear. Since many types of engines all adopt several mushroom valves arranged in a row, it is possible to drive all the guide plates simultaneously with a rotating shaft 30 with a plurality of convex petals 31 .

Figure 17b shows another example where the shaft 30 allows the guide plate 18 to rotate. The shaft 30 with the convex flap 31 rotates in the opening 134 to rotate the guide plate about the pivot 135 . If the guide plate is mounted with a pivot as shown in Figure 9, when the shaft 30 rotates it will drive the guide plate to rotate and increase or decrease the difference between the guide plate path and the rocker arm path, thereby affecting the valve. influence on the motion characteristics. Since the structural design of the opening 134 is used to drive the guide plate 18 to rotate, its side wall 136 is longer than the side wall 137 .

In the above example, the rocker arm swings when the guide plate moves linearly or rotationally. It can be readily seen that the rocker arm can also move linearly in response to the movement of the slide pin within the path of the guide plate. Alternatively, the position of the guide plate can be fixed and all adjustment movements can take place only on the rocker arm, ie the rocker arm can move its pivot relative to the guide plate. The advantage of this arrangement is that after the guide plate is fixed, all adjustment movements are undertaken by the rocker arm, which greatly simplifies the installation of the guide plate.

As can be seen from the examples given, movement of guide plate 18 from its first position to its second position causes slide pin 26 to move along path 25, thereby increasing not only the crankshaft angle over which the valve opens, but simultaneously increasing valve lift. The result of the combination of these aspects is very desirable, because only changing one parameter (such as the movement of the guide plate) can change the two kinematic characteristics of the valve. It is advisable to increase the valve lift when the engine is running at high speed, because this can ensure that the maximum amount of air enters the cylinder and also can clean the exhaust gas from the cylinder. However, it can be seen that at low speeds, it is necessary to increase the intake swirl, which will help the atomization of fuel in the air. Because when the engine is running at a low speed, the air speed entering the cylinder is also low, so the air entering the cylinder through the intake valve will not produce a large swirl. It can also be seen that reducing the valve lift and the opening duration of the valve can increase the intake swirl, so it can increase the degree of fuel atomization and increase the low-speed torque. When the engine is running at high speed, the vortex formed by the fast-flowing air can provide enough energy to atomize the fuel. At this time, the limiting factor is the amount of air squeezed into the cylinder. The invention can ensure that only adjusting one parameter can not only adjust the opening duration of the flow valve, but also adjust the lift of the flow valve at the same time.

The kinematic characteristics of the valve can also be changed by changing other factors such as changing the throttle valve position and selecting the timing gear.

It should be noted that it is not essential to increase the valve lift and opening duration when the engine speed increases. In some working environments, when the engine speed increases, reduce the lift and opening duration of the intake and exhaust valves. It may be desirable, for which the invention is also applicable.

Figure 18a shows a guide plate 418 for mechanically controlled valve actuation, which has two branches 420, each having a drive head 32 thereon. The driver head is placed between the upper flange part 422 and the lower flange part 424 at the upper end of the valve 1 . The valve 1 has a threaded portion 426, on which a lower nut 425 including a lower flange 424 is screwed, as shown in FIG. 18b. An upper nut 428 comprising an upper flange member 422 is also screwed onto the threaded portion 426 of the valve 1 . The interval between the upper flange part 422 and the lower flange part 424 can be set with an intermediate spacer (not shown in the figure), the spacer is plugged between the upper nut 428 and the lower nut 425, the spacer The thickness will determine the separation distance between the upper flange piece 422 and the lower flange piece 424 .

In the illustrated example, upper flange member 422 includes a spacer sleeve 423 which contacts a corresponding spacer sleeve 427 on lower flange member 424 to ensure proper spacing between the two flange members. Usually, the size of this interval should be slightly larger than the diameter of the valve driving head 32 which is in contact with the upper and lower flange parts, so that there is a certain gap between the flange parts and the driving head. For upper and lower nuts, they should be positioned respectively by lock nuts (not shown in the figure). If you want to adjust the flow valve clearance, you can unscrew the upper lock nut (if any), then take off the upper nut 428 with the upper flange 422 and the spacer 423, and use a flange with a spacer with a suitable size Replace the removed upper flange part 422 with a piece, and then re-screw the lock nut onto the threaded part of the valve 1. Adjusting the valve clearance in this way can take into account the wear and tear of the system without changing the guide plate 418 . The spacer 423 and the upper flange can be integrated or separated, and the lower flange 424 and the spacer 427 can also be replaced if necessary.

One alternative is that the upper nut 428 and the upper flange member 422 can be locked in a fixed position by the upper nut 428, and the interval between the upper and lower flange members can be set by adjusting the upper nut 428 and the upper flange member 422. position to adjust.

It is very important that the radius of the contact surface of the drive head 32 remains constant, because this will ensure that the valve clearance remains constant when the valve is opened and closed, and that the rocker arm 16 is free to rotate about the pivot 14.

Claims (26)

CLAIMS 1. A device for adjusting the kinematic characteristics of a flow valve. 2. Apparatus according to claim 1 including a regulator operating between the valve drive mechanism and the valve. 3. The device according to claim 1 or 2, wherein the regulator can change the opening angle of the valve and the closing angle of the valve. 4. Apparatus according to claim 1 or 2, wherein said regulator is capable of varying the lift of the valve. 5. Apparatus according to any one of claims 2 to 4, wherein said valve drive mechanism comprises a reciprocating rotary member. 6. The apparatus of claim 5, wherein said rotating member comprises a crankshaft. 7. Apparatus according to any preceding claim, wherein said adjuster is mechanical. 8. Apparatus according to any preceding claim, wherein said valve actuation mechanism comprises a guide element which moves in a cylindrical shape. 9. Apparatus according to any one of claims 2-8, wherein the adjuster comprises a guide element having a path for receiving the slide. 10. The device according to claim 9, wherein the guide element is movable from a first position to a second position, and when the adjuster is in the first position, the slider in the guide path of the guide element has a motion trajectory , which is different from the trajectory of the slider when the regulator is in the second position. 11. Apparatus according to any one of claims 3-10, wherein the opening and closing angles of the valve relative to the crankshaft position are variable between two predetermined angles. 12. The device according to claim 11, wherein at least three opening and closing angles of the valve should be selectable within the engine speed range. 13. An apparatus for adjusting the movement characteristic of a flow valve, comprising a regulator, the means adjusting the movement of the flow valve according to the displacement movement of a non-linear path. 14. The device according to claim 13, wherein said regulator has a guide element and a guide member, wherein the guide member moves along a guide path of the guide member and along a guide path of the valve drive mechanism. The path moves, causing the valve actuator to move. 15. Apparatus according to claim 13, comprising a pivotable rocker arm, a guide plate adjustable relative to the pivot axis, and a drive for driving the guide along the path of the rocker arm and the path of the guide plate. The device wherein the guide path difference is smaller when the guide plate is in the first position than when the guide plate is in the second position. 16. Apparatus according to any one of the preceding claims, wherein the kinematics of the intake valve is varied independently of the kinematics of the exhaust valve. 17. An adjustment device for adjusting the kinematics of a throttle valve, comprising a plate having a guide path. 18. The device of claim 17, comprising a valve actuator having a guide path different from the guide path of the regulator. 19. The device according to claim 17, wherein the offset of the actuator guide path from the valve actuator guide path determines the kinematic characteristics of the valve actuator. 20. The apparatus of claim 18, wherein changing the position of the adjuster changes the alignment between the adjuster guide path and the valve actuator guide path to adjust the kinematic characteristics of the throttle valve. 21. A device for adjusting the kinematic characteristics of a flow valve, comprising a first guide path and a second guide path, wherein the kinematic characteristics of the valve depend on a difference in shape and/or between the first and second guide paths Alignment difference. 22. Apparatus according to any one of the preceding claims including a mechanically controlled valve drive mechanism. 23. A valve clearance adjustment device driven by a mechanically controlled valve drive mechanism further comprising a valve with threaded ends. 24. The apparatus of claim 23, wherein the valve actuator is located between the lower flange member and the upper flange member, the upper flange member being threaded onto the threaded portion of the valve. 25. The apparatus of claim 24, wherein the upper flange portion and the lower flange portion are separated by spacers. 26. Apparatus according to any one of the preceding claims, wherein the valve actuator has a valve contact surface of substantially constant radius.

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