CN211777634U - Internal combustion engine cylinder brake device - Google Patents

Abstract

The utility model relates to an internal cylinder brake device of an internal combustion engine, which comprises an exhaust valve bridge, wherein an exhaust valve is arranged on the exhaust valve bridge; one end of the rocker arm is connected with the cam; the upper end of the valve adjusting bolt is connected with the other end of the rocker arm, and the lower end of the valve adjusting bolt is connected with a mounting seat positioned above the exhaust valve bridge through a ball head structure; the movable seat is arranged in the exhaust valve bridge and can move up and down relatively, and the movable seat keeps the trend of abutting against the lower end surface of the mounting seat under the action of a fourth elastic piece; the oil duct is used for switchably communicating a lubricating oil inlet or a high-pressure oil inlet with the rocker arm, the valve adjusting bolt, the mounting seat and the movable seat to the exhaust valve bridge in sequence; the elastic valve rod is driven by the fourth elastic piece; the stroke limiting component is arranged on the cylinder cover; when the braking in the cylinder takes effect, the movable seat moves upwards, the exhaust valve bridge moves downwards, the lower part of the elastic valve rod is abutted against the stroke limiting part, the outlet of the elastic valve rod is opened, and high-pressure oil is leaked, so that the accuracy and the reliability of the exhaust valve gap are improved.

Description

Internal combustion engine cylinder brake device

Technical Field

The utility model belongs to the technical field of automobile-used engine exhaust braking, concretely relates to internal-combustion engine jar internal braking device.

Background

With the continuous development of road transportation in China, various medium and large-sized passenger vehicles, medium and heavy commercial vehicles enter the transportation field of different industries, and the safety in the transportation process is the first thing of our wait. The braking performance of the automobile in transportation is very important, and particularly, the driving safety is not optimistic when the automobile runs on a long downhill. When the driver is on a long downhill, the driver needs to frequently use the brake to brake and decelerate, so that the brake is overheated, and the braking efficiency of the brake is gradually reduced and fails. The long-gradient road is more serious when being added on a rugged mountain road, and a large water tank is arranged on the back of a medium-heavy commercial automobile for watering and forcibly cooling a brake hub, so that the serious consequence of fatigue cracking of the hub can be accelerated, and great threat can be certainly caused to the driving safety of the automobile. Particularly in cold winter, the brake hub is watered and forcibly cooled, and the cooled water flows to the ground to be frozen, so that great potential safety hazards are directly caused to the running and life of the following vehicle.

In order to ensure the safe running of medium and large-sized passenger vehicles, medium and heavy commercial vehicles on long downhill slopes and rugged mountain roads and long downhill slopes and improve the transportation conditions, although a plurality of braking modes are available at present, in order to consider the reliability, safety and economy of the braking of the running vehicles, the search and search for an optimal solution of in-cylinder braking of the internal combustion engine are urgent.

To the above problem, chinese utility model patent with patent number CN200820018742.7 (publication number CN201184224Y) discloses "exhaust valve arresting gear for four-valve engine", including exhaust valve, exhaust valve bridge, install the rocker arm structure who is used for opening the exhaust valve on the cylinder head, fix the power device who is used for driving the rotation of rocker arm structure below the rocker arm structure, be located the exhaust valve bridge top and be used for sealing the valve adjusting bolt subassembly of oil and draining to and cylinder block, cylinder head oil way passageway. The braking device is kept open by controlling the exhaust valve, so that the work of gas in the combustion chamber on the piston is reduced, the braking power is improved, and the speed of the whole vehicle is reduced; the vehicle speed is reduced when the vehicle descends a slope for a long time.

However, the structure of the brake device only can improve the brake efficiency, and the problems that noise is caused by the existence of a gap and high-pressure oil impacts an exhaust valve bridge due to the air in an oil passage and the like are also important problems troubling designers in the use process of the internal combustion engine.

SUMMERY OF THE UTILITY MODEL

The utility model discloses the first technical problem that will solve is to prior art's current situation, provides one kind and reveals in order to improve the internal-combustion engine jar arresting gear of braking effect through making braking high-pressure oil trace.

The utility model discloses the second technical problem that will solve is to prior art's current situation, provides one kind and can reduce the internal-combustion engine cylinder arresting gear of clearance with noise reduction.

The utility model discloses the third technical problem that will solve is to prior art's current situation, provides the internal-combustion engine jar internal braking device who does not have the air in the oil duct.

The utility model provides a technical scheme that three technical problem of above-mentioned technique adopted does: an in-cylinder brake device for an internal combustion engine, comprising

The exhaust valve bridge is provided with an exhaust valve;

one end of the rocker arm is connected with the cam;

the upper end of the valve adjusting bolt is connected with the other end of the rocker arm, and the lower end of the valve adjusting bolt is connected with a mounting seat positioned above the exhaust valve bridge through a ball head structure;

it is characterized by also comprising

The movable seat is arranged in the exhaust valve bridge and can move up and down relatively, and the movable seat keeps the trend of abutting against the lower end surface of the mounting seat under the action of a fourth elastic piece;

the oil duct is used for switchably communicating a lubricating oil inlet or a high-pressure oil inlet with the rocker arm, the valve adjusting bolt, the mounting seat and the movable seat to the exhaust valve bridge in sequence;

the elastic valve rod driven by the fourth elastic part is arranged in the exhaust valve bridge and extends downwards through an outlet of the oil duct;

the stroke limiting component is arranged on the cylinder cover, when the cylinder is braked to work, the movable seat moves upwards, the exhaust valve bridge moves downwards, the lower part of the elastic valve rod is abutted against the stroke limiting component, and the outlet of the elastic valve rod is opened to leak high-pressure oil.

In order to enable the oil duct to be communicated with the lubricating oil inlet or the high-pressure oil inlet sequentially with the rocker arm, the valve adjusting bolt, the mounting seat and the movable seat and then to the exhaust valve bridge in a switchable manner, the oil duct comprises a first oil duct arranged on the rocker arm, two second oil ducts for respectively supplying lubricating oil and high-pressure oil to flow into the first oil duct, a third oil duct sequentially penetrating through the valve adjusting bolt, the mounting seat and a fourth oil duct sequentially penetrating through the movable seat and the bottom of the exhaust valve bridge, under the condition that one of the second oil ducts is in fluid communication with the first oil duct, the other second oil duct is disconnected with the first oil duct, and the third oil duct is communicated between the first oil duct and the fourth oil duct.

In order to enable the elastic valve rod to open and close the outlet, the elastic valve rod comprises a limiting rod movably arranged in the outlet of the fourth oil duct in a penetrating mode and a blocking portion formed at the upper end of the limiting rod in the radial mode, the blocking portion is located in the fourth oil duct and can block the outlet, and the stroke limiting part is an upright column which is arranged below the exhaust valve bridge and can abut against the lower end of the limiting rod. When the exhaust valve bridge moves downwards and the limiting rod abuts against the upright post, the exhaust valve bridge continues to move downwards for a small stroke, and the limiting rod slightly moves upwards relative to the exhaust valve bridge, so that the outlet has a small opening degree, and a small amount of braking high-pressure oil is leaked from the outlet; when the pressure is reduced or disappears, the exhaust valve bridge moves upwards under the action of the valve spring, the outlet is shielded by the shielding part again, and the exhaust valve bridge continues to move upwards to drive the elastic valve rod to move upwards along with the exhaust valve bridge.

The braking device is ingenious and reasonable in structural design, when the exhaust valve bridge moves upwards, the outlet of the fourth oil duct can be automatically closed by the elastic valve rod, a driving part which needs to drive the elastic valve rod to close the outlet does not need to be arranged, and related parts are few; and the stroke limiting component is a column, so that the structure is simple.

In order to enable lubricating oil or braking high-pressure oil entering the third oil duct to only flow into the fourth oil duct and not to reversely flow back to the third oil duct from the fourth oil duct, a first one-way valve located in the fourth oil duct is arranged in the movable seat, the first one-way valve comprises a U-shaped first valve seat, a first valve ball arranged in the first valve seat and a first elastic piece acting on the first valve ball, the first valve ball is arranged close to an inlet of the fourth oil duct, and the first elastic piece enables the first valve ball to keep a tendency of shielding the inlet.

In order to facilitate the arrangement of a fourth elastic part and enable the force exerted by the fourth elastic part to directly or indirectly act on the movable seat, a limiting groove is formed in the inner wall of the movable seat, a limiting flange capable of abutting against the top wall and the bottom wall of the limiting groove is formed in the outer wall of the first valve seat, the fourth elastic part is a spring, one end of the fourth elastic part abuts against the elastic valve rod, and the other end of the fourth elastic part abuts against the limiting flange; the fourth elastic member also can play a role in enabling the elastic valve rod to shield the opening of the fourth oil duct.

In order to disconnect one of the second oil ducts from the first oil duct in a state that the other second oil duct is in fluid communication with the first oil duct, the two second oil ducts are respectively a lubricating oil duct in fluid communication with a lubricating oil inlet and a high-pressure oil duct in fluid communication with a high-pressure oil inlet, a second one-way valve which only allows lubricating oil to flow into the first oil duct from the lubricating oil duct is arranged between the first oil duct and the lubricating oil duct, and a third one-way valve which only allows high-pressure oil to flow into the first oil duct from the high-pressure oil duct is arranged between the first oil duct and the high-pressure oil duct. Therefore, when the lubricating oil flows into the first oil duct, no high-pressure oil exists due to the action of the third one-way valve, and the lubricating oil cannot flow into the high-pressure oil duct; when the high-pressure oil flows into the first oil passage, the lubricating oil cannot flow into the first oil passage due to the action of the second check valve.

The second check valve may have various structural forms, and preferably, the second check valve includes a second valve body disposed on the rocker arm, a second passage communicating the lubricant oil duct and the first oil duct is formed in the second valve body, a second valve seat, a second valve ball disposed in the second valve seat, and a second elastic member acting on the second valve ball are disposed in the second passage, and the second elastic member makes the second valve ball keep a tendency of blocking a port of the second passage close to the lubricant oil duct.

The third check valve may have various structural forms, and preferably, the third check valve includes a third valve body disposed on the rocker arm, the third valve body is provided with a third channel communicating the high-pressure oil duct and the first oil duct, a third ball and a third elastic member acting on the third ball are disposed in the third channel, and the third elastic member makes the third ball keep a tendency of blocking a port of the third channel close to the high-pressure oil duct.

In order to facilitate the feeding of lubricating oil or high-pressure oil, the rocker arm is arranged on the rocker arm shaft, and a lubricating oil inlet and a high-pressure oil inlet are formed in the rocker arm shaft, wherein the lubricating oil inlet is in fluid communication with a lubricating oil duct, and the high-pressure oil inlet is in fluid communication with a high-pressure oil duct.

Preferably, a bushing is arranged between the rocker arm and the rocker arm shaft, and the bushing is provided with a first through hole for communicating the lubricating oil inlet with the lubricating oil duct and a second through hole for communicating the high-pressure oil inlet with the high-pressure oil duct. When the rocker arm made of steel materials is used, the rocker arm bushing is not used if other materials with good friction performance are adopted.

In order to enable the movable seat and the exhaust valve bridge to be well matched, a movable seat hole is formed in the exhaust valve bridge, the movable seat can be movably arranged in the movable seat hole, and the movable seat hole is communicated with an oil duct on the exhaust valve bridge.

The structure is simple, the lower end of the valve adjusting bolt is of a ball head structure, and the mounting seat is provided with a ball socket matched with the ball head structure. Thus, the ball head structure is directly formed on the valve adjusting bolt without being separately arranged.

Compared with the prior art, the utility model has the advantages that: 1. the utility model discloses a arresting gear is equipped with the elasticity valve rod that can shelter from or open the export of fourth oil duct, get into braking high pressure oil in the oil duct and when the air release door bridge moves down under high pressure oil pressure, the less aperture can be opened with the export to the elasticity valve rod to make minute braking high pressure oil reveal, the accuracy and the reliability in exhaust valve clearance have been improved, so through the action that changes engine exhaust valve, when compression stroke is about to end, open the exhaust valve, discharge high pressure gas to the blast pipe in, release the energy, make the engine become the air compressor who absorbs the energy, consume whole car kinetic energy and potential energy, the internal-combustion engine brakes with the mode of compression release, the braking reliability of vehicle that traveles like this, security and economic nature can obtain very big improvement and improvement; in addition, the exhaust valve can be opened again when the air inlet is finished, high back pressure gas (air when braking) of the whole vehicle is flushed into the cylinder, and the braking power is further improved;

2. because lubricating oil carries out the clearance filling to the sliding seat inside, the clearance has been overcome, and the sliding seat keeps the trend that offsets with the lower terminal surface of mount pad under the elastic action of fourth elastic component, the mount pad links to each other with valve adjusting bolt, there is not the clearance between mount pad and the sliding seat like this, and if have the clearance between cam and the rocking arm, the rocking arm also can slightly swing under the effect of the power that the sliding seat exerted on the mount pad in order to overcome this clearance, so under the operating mode of normal operating of internal-combustion engine, because the valve clearance is minimum (almost to zero clearance), the noise of the whole driving chain of rocker mechanism has been reduced, NVH performance has been improved, the life of the whole driving chain part of internal-combustion engine rocker mechanism has also been increased simultaneously.

3. Under the working condition of exhaust braking operation of the internal combustion engine, because the whole oil duct is filled with lubricating oil before the braking operation working condition is switched, when the oil duct rapidly enters braking high-pressure oil (except the lubricating oil duct and the second one-way valve), no air (compressible air) exists in the whole oil duct under the state, the phenomenon that the braking high-pressure oil instantaneously impacts an exhaust valve bridge can not be generated, and the timeliness, the reliability and the safety of exhaust braking are improved;

therefore, the utility model discloses a arresting gear can reach above-mentioned effect simultaneously under the condition that satisfies normal exhaust braking function.

Drawings

Fig. 1 is a schematic structural diagram of an embodiment of the present invention;

FIG. 2 is a schematic diagram of the oil circuit of FIG. 1 (during exhaust braking operation of the internal combustion engine);

FIG. 3 is a schematic diagram of the oil circuit of FIG. 1 (under normal engine operating conditions);

FIG. 4 is a schematic structural view of the exhaust valve bridge, the first check valve and the movable seat shown in FIG. 1;

FIG. 5 is a schematic view of the second check valve of FIG. 1;

fig. 6 is a schematic structural view of the third check valve in fig. 1.

Detailed Description

The present invention will be described in further detail with reference to the following embodiments.

As shown in fig. 1 to 6, the internal combustion engine cylinder braking device according to the preferred embodiment may be applied to a two-valve or multi-valve cylinder braking device, and includes an exhaust valve bridge 1, a rocker arm 2, a valve adjusting bolt 4, a movable seat 12, an oil passage, an elastic valve rod 5, and a stroke limiting member 6.

The exhaust valve 11 is installed on the exhaust valve bridge 1, the exhaust valve 11 is movably inserted on the valve seat ring 111, the rocker arm 2 is arranged on the rocker arm shaft 24, one end of the rocker arm 2 is connected with the cam 3 through the idler wheel 26, the upper end of the valve adjusting bolt 4 is connected with the other end of the rocker arm 2 and is fixed through the nut 43, the lower end of the rocker arm is connected with the mounting seat 41 through the ball head structure, the mounting seat 41 is located above the exhaust valve bridge 1, the part is the prior art, and the description is omitted. In this embodiment, the lower end of the valve adjusting bolt 4 is a ball head structure 44, and the mounting seat 41 is provided with a ball socket 411 adapted to the ball head structure.

The exhaust valve bridge 1 is provided with a movable seat hole 14, the movable seat 12 is movably arranged in the movable seat hole 14, the exhaust valve bridge 1 and the movable seat 12 can relatively move up and down, and the movable seat 12 keeps moving up and tends to abut against the lower end face of the mounting seat 41 under the action of the fourth elastic element 120.

The oil passages comprise a first oil passage 21, a second oil passage, a third oil passage 42 and a fourth oil passage 13, wherein two second oil passages are provided and respectively used for lubricating oil and high-pressure oil to flow into the first oil passage 21, the other second oil passage is disconnected with the first oil passage 21 under the condition that one second oil passage is in fluid communication with the first oil passage 21, the third oil passage 42 sequentially penetrates through the valve adjusting bolt 4 and the mounting seat 41, the fourth oil passage 13 sequentially penetrates through the movable seat 12 and the bottom of the exhaust valve bridge 1, the first oil passage 21 and the two second oil passages are both arranged on the rocker arm 2, the third oil passage 42 is communicated between the first oil passage 21 and the fourth oil passage 13, and the fourth oil passage 13 is communicated with the movable seat hole 14.

In this embodiment, the two second oil passages are a lubricant oil passage 22 and a high-pressure oil passage 23, the rocker shaft 24 is provided with a lubricant oil inlet 241 in fluid communication with the lubricant oil passage 22 and a high-pressure oil inlet 242 in fluid communication with the high-pressure oil passage 23, a second check valve 8 which only allows lubricant oil to flow into the first oil passage 21 from the lubricant oil passage 22 is arranged between the first oil passage 21 and the lubricant oil passage 22, and a third check valve 9 which only allows high-pressure oil to flow into the first oil passage 21 from the high-pressure oil passage 23 is arranged between the first oil passage 21 and the high-pressure oil passage 23, so when lubricant oil flows into the first oil passage 21, no high-pressure oil exists at this time due to the action of the third check valve 9, and lubricant oil cannot flow into the high-pressure oil passage 23, so as to prevent lubricant oil leakage; when the high-pressure oil flows into the first oil passage 21 through the high-pressure oil passage 23, the high-pressure oil does not flow into the lubricating oil passage 22 through the first oil passage 21 due to the action of the second check valve 8, so that one of the second oil passages is disconnected from the first oil passage 21 in a state where the other second oil passage is in fluid communication with the first oil passage 21.

From the above, the oil passage can switchably communicate the lubricating oil inlet 241 or the high-pressure oil inlet 242 with the rocker arm 2, the valve adjusting bolt 4, the mounting seat 41, the movable seat 12 and the exhaust valve bridge 1 in sequence. In addition, the oil passages in the embodiment may be directly communicated with each other, or may be communicated with each other through other branch oil passages.

In this embodiment, the second check valve 8 includes a second valve body 81 disposed on the rocker arm 2, a second channel 811 for communicating the lubricant oil passage 22 with the first oil passage 21 is opened on the second valve body 81, a U-shaped second valve seat 80, a second valve ball 82 disposed in the second valve seat 80, and a second elastic member 83 acting on the second valve ball 82 are disposed in the second channel 811, and two ends of the second elastic member 83 respectively abut against the second valve seat 80 and the second valve ball 82, so that the second valve ball 82 keeps a tendency of blocking a port of the second channel 811 close to the lubricant oil passage 22.

The third check valve 9 includes a third valve body 91 arranged on the rocker arm 2, a third channel 911 for communicating the high-pressure oil gallery 23 and the first oil gallery 21 is formed in the third valve body 91, a third valve ball 92 and a third elastic member 93 acting on the third valve ball 92 are arranged in the third channel 911, two ends of the third elastic member 93 respectively abut against the rocker arm 2 and the third valve ball 92, so that the third valve ball 92 keeps a tendency of blocking a port of the third channel 911 close to the high-pressure oil gallery 23, and the third channel 911 and the first oil gallery 21 can be provided with an oil gallery branch 27.

For the rocker arm 2 made of steel, a bushing 25 is required to be arranged between the rocker arm 2 and the rocker arm shaft 24, and in order to ensure the communication of the oil passages, the bushing 25 is provided with a first through hole for communicating the lubricating oil inlet 241 with the lubricating oil passage 22 and a second through hole for communicating the high-pressure oil inlet 242 with the high-pressure oil passage 23.

The movable seat 12 is provided with a first check valve 7 located in the fourth oil gallery 13, the first check valve 7 includes a U-shaped first valve seat 71, a first valve ball 72 located in the first valve seat 71, and a first elastic member 73 acting on the first valve ball 72, the first valve ball 72 is disposed adjacent to an inlet 132 of the fourth oil gallery 13, the first elastic member 73 is a spring, and two ends of the spring respectively abut against the first valve seat 71 and the first valve ball 72, so that the first valve ball 72 keeps a tendency of shielding the inlet 132, and therefore, lubricating oil or braking high-pressure oil entering the third oil gallery 42 can only flow into the fourth oil gallery 13, but cannot reversely flow back to the third oil gallery 42 from the fourth oil gallery 13.

The inner wall of the movable seat 12 is provided with a limiting groove 121, the outer wall of the first valve seat 71 is provided with a limiting flange 711 which can abut against the top wall and the bottom wall of the limiting groove 121, the fourth elastic element 120 is a spring, one end of the fourth elastic element abuts against the elastic valve rod 5, and the other end of the fourth elastic element abuts against the limiting flange 711. When the first valve seat 71 abuts against the top wall of the stopper groove 121, the force of the fourth elastic member 120 acting on the first valve seat 71 is transmitted to the movable seat 12, so that the movable seat 12 always tends to abut against the mounting seat 41.

In this embodiment, the elastic valve rod 5 includes a limiting rod 51 movably inserted into the outlet 131 of the fourth oil passage 13, and a blocking portion 52 radially formed at an upper end of the limiting rod 51, and the blocking portion 52 is located in the fourth oil passage 13 and can block or open the outlet 131.

The stroke stop block 6 is a column which is arranged below the exhaust valve bridge 1 and can be abutted against the lower end of the limit rod 51, the column is arranged on the upper end surface 61 of the cylinder cover, when the braking effect-taking exhaust valve in the cylinder is opened to set the program work, the exhaust valve bridge 1 moves downwards, the lower part of the elastic valve rod 5 is abutted against the stroke stop block 6, and the outlet 131 of the elastic valve rod 5 is opened to leak high-pressure oil.

In other words, when the exhaust valve bridge 1 moves downwards and the limit rod 51 abuts against the stroke limit part 6, the exhaust valve bridge 1 continues to move downwards for a small stroke, and the stroke limit part 6 is a fixed part and cannot move downwards, so that the exhaust valve bridge 1 and the elastic valve rod 5 generate slight relative motion, the outlet 131 is opened for a small opening, and a small amount of braking high-pressure oil leaks from the outlet 131; when the pressure is reduced or disappears, the exhaust valve bridge 1 moves upwards under the action of the valve spring, the outlet 131 is shielded by the shielding part 52 again, and the exhaust valve bridge 1 continues to move upwards to drive the elastic valve rod 5 to move upwards along with the upward movement.

The operation of the in-cylinder brake device of the internal combustion engine of the embodiment is as follows:

under the working condition of normal operation of the internal combustion engine:

the cam 3 drives the rocker arm 2, and drives the exhaust valve bridge 1 and the exhaust valve 11 to perform normal actions through the valve adjusting bolt 4 and the mounting seat 41.

As shown in fig. 3, at the same time, the lubricating oil of the internal combustion engine passes through the lubricating oil inlet 241 on the rocker shaft 24, the first through hole on the bush 25, the lubricating oil gallery 22, the second check valve 8 in order, enters the first oil gallery 21, and then passes through the third oil gallery 42 into the fourth oil gallery 13 of the exhaust valve bridge 1 in a state where the second check valve 8 is open (at which time the third check valve 9 is closed). At this time, the rocker arm 2 performs a high-speed swinging motion, the first valve ball 72 of the first check valve 7 enables oil to enter the fourth oil passage 13, under the action of the kinetic energy of the rocker arm swinging at a high speed, the first valve ball 72 is in a micro-opening and closing state (the first valve ball 72 slightly opens the inlet 132 of the fourth oil passage 13 under the action of the self gravity), meanwhile, the movable seat 12 moves upwards under the action of the fourth elastic member 120 to abut against the lower end surface of the mounting seat 41, a small amount of lubricating oil fills the clearance space inside the movable seat 12 through the first check valve 7, and because the movable seat 12 always tends to abut against the lower end surface of the mounting seat 41 under the elastic action of the fourth elastic member 120, there is no clearance between the mounting seat 41 and the movable seat 12, and the mounting seat 41 is connected with the valve adjusting bolt 4, if there is a clearance between the cam 3 and the rocker arm 2, the rocker arm 2 also slightly swings under the action of the force exerted on the mounting seat 41 by the movable seat 12 to overcome the clearance, so under the operating mode of internal-combustion engine normal operating, because the valve clearance is minimum (almost to zero clearance), reduced the noise of the whole driving chain of rocking arm 2, improved NVH performance, also increased the life of the whole driving chain part of internal-combustion engine rocking arm 2 simultaneously to valve clearance and the clearance between cam 3 and the gyro wheel 26 have been eliminated by a wide margin, also supplemented the clearance after whole driving chain weares and decreases simultaneously.

In addition, because the working pressure of lubricating oil in the rocker arm 2 is extremely low at the moment, the exhaust valve 11 cannot be pushed to leave the valve seat ring 111 when the valve is normally closed, and meanwhile, the friction surface between the exhaust valve bridge 1 and the exhaust valve 11 is lubricated, and because the valve clearance is extremely low, the noise of the whole transmission chain of the rocker arm 2 is reduced.

The oil passage under the normal operation condition of the internal combustion engine is shown by a dotted arrow in fig. 3.

Under the working condition of the exhaust brake operation of the internal combustion engine:

as shown in fig. 2, when the exhaust brake is operated, the brake high-pressure oil of the internal combustion engine passes through the high-pressure oil inlet 242 on the rocker shaft 24, the second through hole on the bushing 25, the high-pressure oil passage 23, and the third check valve 9 in sequence under the state that the third check valve 9 is open (at this time, the second check valve 8 is in the closed state under the action of the high-pressure oil), enters the first oil passage 21, then the brake high-pressure oil rapidly opens the first check valve 7 through the third oil passage 42, and continuously and rapidly injects the high-pressure oil into the fourth oil passage 13 inside the movable seat 12, under the pressure of the high-pressure oil, the movable seat 12 rapidly moves upwards and always abuts against the lower end surface of the mounting seat 41, the exhaust valve bridge 1 is forced to rapidly move downwards, when the exhaust valve bridge 1 moves downwards and touches the stroke limiting part 6 at the bottom of the limiting rod 51 on the elastic valve rod 5, a slight relative motion is generated between the exhaust valve bridge 1 and the, the outlet 131 of the fourth oil duct 13 is opened by a small opening degree, a small amount of brake high-pressure oil is released, at this time, the first valve ball 72 is basically in a closed state, but the inlet 132 of the fourth oil duct 13 cannot be absolutely closed, the brake high-pressure oil can continuously enter the fourth oil duct 13 of the movable seat 12, and the exhaust valve bridge 1 enters a balance state in the state, so that the exhaust brake of the brake structure device in the cylinder of the internal combustion engine can normally operate.

Under the working condition, the lubricating oil of the internal combustion engine still works according to the working condition of normal operation of the internal combustion engine, and only can not enter the first oil duct 21 through the second one-way valve 8, so that when the braking high-pressure oil enters the first oil duct 21, the whole oil duct is free of air, the phenomenon that the high-pressure oil instantaneously impacts the exhaust valve bridge 1 can not be generated, and the timeliness, the reliability and the safety of exhaust braking are improved.

The oil path in this condition of the exhaust brake operation of the internal combustion engine is shown by the dotted arrow in fig. 2.

Under the working condition of releasing the exhaust braking operation of the internal combustion engine:

the engine oil is still in the condition of normal operation of the engine, but cannot enter the first oil passage 21 through the second check valve 8, when the internal combustion engine cuts off braking high-pressure oil to enter the exhaust valve bridge 1, the rocker arm 2 of the internal combustion engine still operates in normal swing, after the brake high-pressure oil is lost inside the movable seat 12, the brake high-pressure oil leaks out between the ball head structure of the valve adjusting bolt 4 and the ball socket of the mounting seat 41, between the bottom surface of the mounting seat 41 and the upper end surface of the movable seat 12, and between the movable seat 12 and the movable seat hole 14, at the same time, the movable seat 12 is quickly decompressed and sinks, the exhaust valve bridge 1 is quickly lifted under the action of a valve spring (not shown in the figure), the elastic valve rod 5 leaves the stroke limiting component 6, the outlet 131 of the fourth oil duct 13 is closed, and at the same time, the first valve ball 72 and the second valve ball 82 are opened, so that the lubricating oil enters and is restored to the working condition state of normal operation of the internal combustion engine as shown in figure 3.

Claims (10)

1. An in-cylinder brake device for an internal combustion engine, comprising

The exhaust valve bridge (1) is provided with an exhaust valve (11);

one end of the rocker arm (2) is connected with the cam (3);

the upper end of the valve adjusting bolt (4) is connected with the other end of the rocker arm (2), and the lower end of the valve adjusting bolt is connected with a mounting seat (41) positioned above the exhaust valve bridge (1) through a ball head structure;

it is characterized by also comprising

The movable seat (12) is arranged in the exhaust valve bridge (1) and can move up and down relatively, and the movable seat (12) keeps the trend of abutting against the lower end face of the mounting seat (41) under the action of a fourth elastic piece (120);

the oil passage is used for switchably communicating a lubricating oil inlet (241) or a high-pressure oil inlet (242) with the rocker arm (2), the valve adjusting bolt (4), the mounting seat (41), the movable seat (12) and the exhaust valve bridge (1) in sequence;

the elastic valve rod (5) driven by the fourth elastic piece (120) is arranged in the exhaust valve bridge (1) and extends downwards through an outlet (131) of the oil channel;

the stroke limiting component (6) is arranged on the cylinder cover (61), when the braking in the cylinder works, the movable seat (12) moves upwards, the exhaust valve bridge (1) moves downwards, the lower part of the elastic valve rod (5) is abutted against the stroke limiting component (6), and the elastic valve rod (5) opens the outlet (131) to leak high-pressure oil.

2. The in-cylinder brake apparatus for an internal combustion engine according to claim 1, characterized in that: the oil passages comprise a first oil passage (21) arranged on the rocker arm (2), two second oil passages for respectively allowing lubricating oil and high-pressure oil to flow into the first oil passage (21), a third oil passage (42) sequentially penetrating through the valve adjusting bolt (4) and the mounting seat (41), and a fourth oil passage (13) sequentially penetrating through the movable seat (12) and the bottom of the exhaust valve bridge (1), wherein in the state that one second oil passage is in fluid communication with the first oil passage (21), the other second oil passage is disconnected with the first oil passage (21), and the third oil passage (42) is communicated between the first oil passage (21) and the fourth oil passage (13).

3. The in-cylinder brake apparatus for an internal combustion engine according to claim 2, characterized in that: the elastic valve rod (5) comprises a limiting rod (51) movably arranged in an outlet (131) of the fourth oil channel (13) in a penetrating mode and a blocking portion (52) formed at the upper end of the limiting rod (51) in the radial mode, the blocking portion (52) is located in the fourth oil channel (13) and can block the outlet (131), and the stroke limiting part (6) is an upright column which is arranged below the exhaust valve bridge (1) and can abut against the lower end of the limiting rod (51).

4. The in-cylinder brake device for an internal combustion engine according to claim 3, characterized in that: a first check valve (7) located in the fourth oil channel (13) is arranged in the movable seat (12), the first check valve (7) comprises a U-shaped first valve seat (71), a first valve ball (72) arranged in the first valve seat (71) and a first elastic piece (73) acting on the first valve ball (72), the first valve ball (72) is arranged adjacent to an inlet (132) of the fourth oil channel (13), and the first elastic piece (73) enables the first valve ball (72) to keep a tendency of shielding the inlet (132).

5. The in-cylinder brake device for an internal combustion engine according to claim 4, characterized in that: be equipped with spacing groove (121) on the inner wall of sliding seat (12), shaping can be with spacing flange (711) that the roof and the diapire of spacing groove (121) offset on the outer wall of first disk seat (71), fourth elastic component (120) are the spring, and one end and elasticity valve rod (5) offset, and the other end and spacing flange (711) offset.

6. The in-cylinder brake apparatus for an internal combustion engine according to claim 2, characterized in that: the two second oil ducts are respectively a lubricating oil duct (22) in fluid communication with the lubricating oil inlet (241) and a high-pressure oil duct (23) in fluid communication with the high-pressure oil inlet (242), a second one-way valve (8) which only allows lubricating oil to flow into the first oil duct (21) from the lubricating oil duct (22) is arranged between the first oil duct (21) and the lubricating oil duct (22), and a third one-way valve (9) which only allows high-pressure oil to flow into the first oil duct (21) from the high-pressure oil duct (23) is arranged between the first oil duct (21) and the high-pressure oil duct (23).

7. The in-cylinder brake apparatus for an internal combustion engine according to claim 6, characterized in that: the second check valve (8) comprises a second valve body (81) arranged on the rocker arm (2), a second channel (811) communicated with the lubricating oil duct (22) and the first oil duct (21) is formed in the second valve body (81), a second valve seat (80), a second valve ball (82) arranged in the second valve seat (80) and a second elastic piece (83) acting on the second valve ball (82) are arranged in the second channel (811), and the second valve ball (82) is enabled to keep a trend of blocking a port, close to the lubricating oil duct (22), of the second channel (811) through the second elastic piece (83).

8. The in-cylinder brake apparatus for an internal combustion engine according to claim 6, characterized in that: the third check valve (9) comprises a third valve body (91) arranged on the rocker arm (2), a third channel (911) for communicating the high-pressure oil duct (23) with the first oil duct (21) is formed in the third valve body (91), a third valve ball (92) and a third elastic piece (93) acting on the third valve ball (92) are arranged in the third channel (911), and the third elastic piece (93) enables the third valve ball (92) to keep a tendency of plugging a port, close to the high-pressure oil duct (23), of the third channel (911).

9. The in-cylinder brake apparatus for an internal combustion engine according to claim 6, characterized in that: a bushing (25) is arranged between the rocker arm (2) and the rocker arm shaft (24), and a first through hole for communicating a lubricating oil inlet (241) with a lubricating oil duct (22) and a second through hole for communicating a high-pressure oil inlet (242) with a high-pressure oil duct (23) are formed in the bushing (25).

10. The in-cylinder brake apparatus for an internal combustion engine according to claim 1, characterized in that: the exhaust valve bridge is characterized in that a movable seat hole (14) is formed in the exhaust valve bridge (1), the movable seat (12) can be movably arranged in the movable seat hole (14), and the movable seat hole (14) is communicated with an oil duct on the exhaust valve bridge (1).

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