CN219638910U

CN219638910U - Variable exhaust valve mechanism of engine

Info

Publication number: CN219638910U
Application number: CN202320679090.6U
Authority: CN
Inventors: 王慧; 安洋; 崔生乐
Original assignee: Northeast Forestry University
Current assignee: Northeast Forestry University
Priority date: 2023-03-30
Filing date: 2023-03-30
Publication date: 2023-09-05
Anticipated expiration: 2033-03-30

Abstract

The utility model provides an engine variable exhaust valve mechanism. The device comprises an input shaft, an eccentric slide block, a push rod roller, an eccentric shaft I, an eccentric shaft II, a valve push rod I, a valve push rod II, a slide block pin I and a slide block pin II. The eccentric sliding block is fixed in the linear bearing of the engine and can move transversely, and two circular grooves are formed in the eccentric sliding block and are matched with the eccentric shaft I and the eccentric shaft II respectively. The eccentric sliding block at the center of rotation of the eccentric shaft I and the eccentric shaft II moves to move. The first eccentric shaft is provided with a cam, the second eccentric shaft is matched with a push rod roller, and the push rod roller is contacted with the cam on the first eccentric shaft to form cam matching. The input shaft is fitted in the engine bearing housing. The input shaft is provided with a pin hole which is matched with the first slider pin. The eccentric sliding block I is provided with a groove which is matched with the sliding block pin I to form a hinge. Two grooves with different angles are formed on the eccentric sliding block II and are respectively in hinge fit with the sliding block pin II and the sliding block. The second sliding block pin is matched with the second pin hole of the valve push rod, and the sliding block is matched with the first sliding groove of the valve push rod.

Description

Variable exhaust valve mechanism of engine

Technical Field

The utility model belongs to an automobile internal combustion engine part. Is a variable exhaust valve mechanism of an engine.

Background

Energy and emission reduction is the trend of vehicle development; on the one hand, the heat efficiency of the engine needs to be improved, and energy conservation and emission reduction are realized. On the other hand, at limited engine displacement of the vehicle, the host farm tends to boost the engine's boost power and torque as much as possible.

Forest machines such as forest fire control command vehicles often travel on paved surfaces and travel far from gas stations. Therefore, the engine adopted by the forest fire control command vehicle needs to have better low-speed torque, power rise and fuel saving performance.

The engine valve train, and in particular the intake mechanism parameters, have a large impact on engine performance. When the engine is at a low speed, the exhaust valve of the engine needs a lower valve lift to increase the exhaust speed, and exhaust back pressure is utilized to enable exhaust to be more thorough, so that the knocking tendency of the engine is reduced, the engine can suck more air, and the low speed torque of the engine is increased. And simultaneously, the faster exhaust speed of the turbocharged engine is beneficial to reducing the turbo lag.

Meanwhile, when the engine is at a low rotation speed, exhaust valve duration is reduced, exhaust gas backflow is prevented, exhaust is facilitated, and engine knocking tendency is reduced. For a DOHC engine, the variable exhaust manifold may be operated by further reducing one of the exhaust valve lifts and durations at low engine speeds.

When the engine is at high rotation speed and high load, on one hand, larger exhaust valve lift is needed, so that exhaust back pressure is reduced, and exhaust is accelerated. On the other hand, by prolonging the duration of the exhaust valve, the exhaust inertia is beneficial to being utilized, so that the exhaust is smoother, the engine rotating speed and high rotating torque are beneficial to being improved, and the power of the engine is improved.

Disclosure of Invention

Aiming at the traditional automobile engine cam linear fixation, only one valve lift and duration can be provided, the two-stage variable valve lift technology can only realize two-stage variable valve lift and duration, the two valve lifts are generally the same, and the continuous variable valve lift needs to be matched with the continuous variable valve timing.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

the variable exhaust valve mechanism of the engine comprises an input shaft, an eccentric sliding block, a push rod roller, an eccentric shaft I, an eccentric shaft II, a valve push rod I, a valve push rod II, a sliding block pin I and a sliding block pin II.

The eccentric sliding block is fixed in the linear bearing of the engine and can move transversely, and two circular grooves are formed in the eccentric sliding block and are matched with the eccentric shaft I and the eccentric shaft II respectively. The eccentric sliding block at the center of rotation of the eccentric shaft I and the eccentric shaft II moves to move. The first eccentric shaft is provided with a cam, the second eccentric shaft is matched with a push rod roller, and the push rod roller is contacted with the cam on the first eccentric shaft to form cam matching. The input shaft is fitted in the engine bearing housing. The input shaft is provided with a pin hole which is matched with the first slider pin. The eccentric sliding block I is provided with a groove which is matched with the sliding block pin I to form a hinge. Two grooves with different angles are formed on the eccentric sliding block II and are respectively in hinge fit with the sliding block pin II and the sliding block. The second sliding block pin is matched with the second pin hole of the valve push rod, and the sliding block is matched with the first sliding groove of the valve push rod.

The input shaft drives the first eccentric shaft through the first sliding block pin, and the first eccentric shaft drives the second eccentric shaft through the cam. The eccentric shaft II drives the valve push rod I and the valve push rod II through the sliding block and the sliding block pin respectively, and the valve push rod I and the valve push rod II push the roller rocker mechanism to push the valve, and the eccentric shaft II is provided with a spring for aligning the mechanism. By changing the rotation center of the eccentric shaft I, the opening angle and the ending angle of the eccentric shaft I, which drives the eccentric shaft II, can be changed, so that the duration of the whole mechanism for driving the valve is changed, and when the included angle between the upper groove of the eccentric shaft I and the horizontal plane is properly set, only the ending angle can be changed, so that the valve timing is realized. By arranging the two grooves of the eccentric shaft II to be different from the horizontal plane in included angle, when the rotation center of the eccentric shaft II is changed, the opening duration and the rotation angle of the valve push rod I and the valve push rod II can be changed, or only the rotation angle can be changed, so that the valve lift and the duration can be changed, or only the valve lift can be changed. The two groove angles are different, when the rotation center of the eccentric shaft II is changed, the rotation angles of the valve push rod I and the valve push rod II can be different, the two valve lifts and the duration can be different, and when the valve lift reaches the maximum value, the two valve lifts can be the same.

Drawings

FIG. 1 is a schematic diagram of the mechanism of the present utility model

FIG. 2 is a view of the parts and positional relationship of the present utility model

In the figure: 1. a valve push rod I; 2. an eccentric shaft II; 3. an eccentric slide block; 4. a first sliding block pin; 5. an eccentric shaft I; 6. an input shaft; 7. a roller rocker arm mechanism II; 8. a pushrod roller; 9. a roller rocker arm mechanism II; 10. valve pushing rod II; 11. a second sliding block pin; 12. a slide block;

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present utility model, but not all embodiments.

Referring to fig. 1 and 2, an input shaft 6, a valve push rod 1 and a valve push rod 10 are respectively fixed in an engine sliding bearing, and an eccentric slide block 3 is fixed in an engine linear bearing. In the input of the eccentric shaft I5 and the eccentric shaft II 2, the eccentric shaft I5 is driven by the slide block pin I4, and the eccentric shaft I5 drives the eccentric shaft II 2 by the cam. The eccentric shaft II 2 is provided with a slide block 12 with the same structure and a slide block pin II 11 to drive the valve push rod I1 and the valve push rod II 10, so that the valve is pushed by the roller rocker mechanism 7, and the eccentric shaft II 2 is provided with a spring for mechanism alignment. The transverse movement of the eccentric sliding block I3 can change the rotation centers of the eccentric shaft I5 and the eccentric shaft II 2, and the change of the rotation center of the eccentric shaft I5 can change the opening and closing angles of the cams, thereby changing the duration of opening the valve and realizing the timing function. The change of the rotation center of the eccentric shaft II 2 can change the valve lift and duration or only change the valve lift, and when the included angle between the groove on the eccentric shaft II 2 and the horizontal plane is different, the two valve lifts and durations can be the same or different.

The words "center of rotation", "lateral movement", "horizontal plane" and the like in this embodiment are merely used to facilitate understanding in the drawings, and changes in the orientation of the actual application should not affect the rights associated with this utility model. The shapes of the springs on the push rod are different, and the related rights of the utility model are not affected.

Claims

1. The utility model provides an engine variable exhaust valve mechanism which characterized in that input shaft (6) are fixed in engine slide bearing, and eccentric slider (3) are fixed in engine linear bearing, have two circular grooves on eccentric slider (3), and eccentric shaft one (5) is fixed in eccentric slider (3) circular groove, has the recess on eccentric shaft one (5) to form hinge cooperation with slider round pin one (4), and slider round pin one (4) and input shaft (6) go up the pinhole cooperation.