CN201372829Y

CN201372829Y - Rocker-valve-bridge compound engine braking device

Info

Publication number: CN201372829Y
Application number: CN200920142242U
Authority: CN
Inventors: 杨洲; 奚勇
Original assignee: Individual
Current assignee: Individual
Priority date: 2009-04-07
Filing date: 2009-04-07
Publication date: 2009-12-30
Anticipated expiration: 2019-04-07

Abstract

The utility model discloses a rocker-valve-bridge compound engine braking device (engine retarding device). The braking device comprises a drive mechanism and a control mechanism. The drive mechanism comprises a brake bearing system mounted on the engine and a brake operation system integrated in a vent valve tap system. The brake bearing system comprises a rocker and a cam and the rocker is offset at an off position. The brake bearing system also comprises a valve clearance adjusting system for setting the valve clearance between the drive mechanism and the vent valve. The brake operation mechanism comprises a brake piston in the valve bridge. The control mechanism makes the brake piston move between the off position and on position. The retraction, drive mechanism of the brake piston is separated from the vent valve in the engine vent valve tap system at off position; the brake piston protrudes at the on position and the vent valve is opened by the drive mechanism to generate engine brake. The device not only increases the height and weight of the engine but also has features of simple structure, reliable run and good brake performance.

Description

Rocking arm-valve bridge composite engine braking device

Technical field

The utility model relates to the internal-combustion engine braking, specially refers to rocking arm-valve bridge composite engine braking device.

Technical background

Is on record with internal-combustion engine as brake tool, only needs motor temporarily is converted to compressor.This conversion can be by cutting off fuel oil, when the engine piston compression stroke finishes or when finishing, open outlet valve, allowing to be compressed gas (being air during braking) is released, the motor energy that pressurized gas absorbed in compression stroke, can not turn back to engine piston at expansion stroke subsequently, but dissipate by the exhaust and the radiation system of motor.Final result is effective engine braking, slows down the speed of vehicle.U. S. Patent discloses a kind of braking system that has dedicated rocker arm No. 5626116.This system contains a hydraulic braking piston, is placed in the piston hole of dedicated rocker arm one end.This piston can be locked at extended position by hydraulic pressure, produces the braking running.Solenoid valve or control valve also are integrated in the dedicated rocker arm.Also have a dedicated cam, only contain the kick part that is useful on braking.Like this, the performance of engine braking can be optimized, and the valve that does not influence the motor normal operation rises curve.When not needing engine braking, brake rocker arm is in neutral position on pitman arm shaft, and the two ends of rocking arm all do not contact any object.One gap is wherein arranged between an end and the cam, and the other end then and between outlet valve or the valve bridge has a gap.Because its braking ability is good, volume is little, obtained certain success commercial according to the engine brake of No. 5626116 patent manufacturing of the U.S..But still there is some shortcoming in this system.One of shortcoming is that brake rocker arm can be from the disengagement of the neutral position on the pitman arm shaft, contact cam and outlet valve when the motor normal operation.So that the brake piston in the rocking arm is subjected to the high frequency bump and gets loose, and causes the damage of motor.Two of the shortcoming of above-mentioned braking system is that the volume of brake rocker arm and rotary inertia are too big.Because all brake fluid pressure parts comprise control valve and hydraulic braking piston, all are integrated in the rocking arm, make it be difficult to install and control.Another shortcoming of above-mentioned braking system is its complexity.Because need the position of accurate control brake rocking arm and the stroke of brake piston, this system must adopt precision parts.Therefore, make complexity, on the high side.

Summary of the invention

The purpose of this utility model is: a kind of engine braking apparatus that can overcome above-mentioned defective is provided.A kind of rocking arm provided by the utility model-valve bridge composite engine braking device (slowing down speed of engine) converts the normal operation of motor to the braking running.Described device comprises driving mechanism and control mechanism.Driving mechanism contains the braking bearing system that is installed on the motor and is integrated in the interior brake-operating system of engine exhaust valve system.Brake-operating system comprises brake piston.Control mechanism makes the brake piston of driving mechanism move between off position and operating position.At off position, brake piston withdrawal, driving mechanism and engine exhaust valve are that contained outlet valve separates; At operating position, brake piston stretches out, and driving mechanism is opened outlet valve, produces the engine braking running.

The braking bearing system of device described in the utility model comprises dedicated rocker arm and brake cam.Dedicated rocker arm is biased on the brake cam by spring.At least one small embossment part is arranged on the brake cam, when brake piston is in operating position, open outlet valve.The braking bearing system also comprises the valve clearance regulating system, in order to set the valve clearance between braking drive organ and the outlet valve.

It is in the contained valve bridge that the brake piston of the brake-operating system of device described in the utility model is integrated in the engine exhaust valve, and is biased in off position by brake spring.

Brake-operating system described in the utility model also comprises limit movement mechanism, in order to the stroke and the rotation of control brake piston.

Device described in the utility model does not increase the height and the weight of motor, and is simple in structure, reliable, and braking ability is good.

Description of drawings

Above-mentioned and other advantages of the present utility model will be more and more obvious from the description of following embodiment or device, and these mode of executions or device are embodied in the following figure.

Fig. 1 is according to a flow chart of the present utility model, describes motor normal operation and the add universal relation of braking running.

Fig. 2 A and 2B are according to the schematic representation of engine braking control mechanism of the present utility model (position of " opening " and " pass ").

Fig. 3 A and 3B are the schematic representation of first embodiment of the present utility model in its " pass " and " opening " position.

Fig. 4 is the schematic representation of a kind of arrangement mode of first embodiment.

Fig. 5 is the schematic representation of a kind of fuel system of first embodiment.

Fig. 6 A and 6B are the schematic representation that is used for first embodiment's different braking piston composition.

Fig. 7 is the schematic representation of second engine braking apparatus embodiment of the present utility model in its off-position.

Embodiment

Now embodiment that the utility model is recommended or device are done detailed examination, and related embodiment has explanation in the drawing of enclosing.Each example all is that the utility model is described, rather than limits it.In fact, those people that are expert at one's trade can show to change places and in scope of the present utility model and principle the utility model made amendment and change.For instance, one is specifically installed certain part of functions illustrated or that describe, can be used for another concrete device, and then obtain a new device.Therefore, the utility model will comprise above-mentioned modification and change, as long as they belong within appended claim or the scope suitable with requirement power.

Flow chart shown in Figure 1 is a part of the present utility model, in order to the universal relation between the braking running 10 of normal operation 20 of explanation motor and interpolation.One outlet valve system 300 and an exhaust valve actuation device 200 are arranged in the typical internal-combustion engine, when the motor normal operation, periodically open and close outlet valve.The engine braking running of adding 10 is that the driving by 50 pairs of engine braking driving mechanisms 100 of engine braking control mechanism realizes.This driving mechanism contains an off position 0 and an operating position 1.When motor when its normal operation 20 is converted to engine braking and operates 10, braking control mechanism 50 need be converted to operating position 1 from off position 0 with braking drive organ 100.Generally, engine braking control mechanism 50 is in the position of " pass ", and engine braking driving mechanism 100 is in off position 0, and this moment, engine braking apparatus separated with outlet valve.

Fig. 2 A and 2B are that a kind of braking control mechanism 50 of engine braking " is opened " and " pass " schematic representation of position at it respectively.When the needs engine braking, the three-way magnetic valve 51 of braking control mechanism 50 is by opening (Fig. 2 A) by the electric current of positive and negative terminal 55 and 57.The spool 58 of solenoid valve 51 glides, and opens oil-feed port 111, allows hydraulic fluid, and for example engine motor oil flows to the fluid networking that is used to brake.This fluid networking is included in fluid passage 211 and the radial hole 212 in the pitman arm shaft 205, the otch 213 and fluid passage 214 (details of relevant exhaust valve actuation device 200 will be set forth below) in rocking arm 210.When not needing engine braking, three-way magnetic valve 51 is closed, and moves on the valve rod 58 and closes oil-feed port 111, opens oil drain out 222, allows machine oil flow out brake fluid networking (Fig. 2 B).If oil drain out 222 is blocked, that is to say that if there is not oil drain out 222, three-way magnetic valve 51 has just become bidirectional electromagnetic valve.The back can be seen, if the brake fluid networking contains discharge orifice, bidirectional electromagnetic valve is just enough.In addition, engine braking control mechanism 50 can be used to control the multicylinder engine braking, and the fluid networking also can relate to the miscellaneous part of motor.

Fig. 3 A and 3B are the schematic representation of first embodiment of engine braking apparatus of the present utility model in its " pass " and " opening " position.It comprises three major components: the driving mechanism 100 of engine brake, exhaust valve actuation device 200 and outlet valve system 300.Exhaust valve actuation device 200 and outlet valve system 300 compositions are commonly referred to as drain tap system.Driving mechanism 100 contains the braking bearing system, makes the exhaust valve actuation device 200 of motor itself not bear huge brake load.The braking bearing system of present embodiment is a special valve actuator 200b, is used for producing the compression-release braking.

Exhaust valve actuation device 200 comprises cam 230, rocking arm 210 and valve bridge 400.Cam 230 has a big convex portion 220 on interior basic circle 225, be used for the normal operation 10 of motor.Be installed on the pitman arm shaft 205, an end has cam follower wheel 235 rocking arm 210 swing types, and the other end then contacts with valve bridge 400.Usually also have the valve clearance adjusting screw and resemble sufficient pad, but for the purpose of concise and to the point, do not list at this.Can install a spring 198 on the rocking arm 210 additional, rocking arm 210 is biased on the valve bridge 400.

The special valve actuator 200b of engine brake comprises special-purpose brake cam 230b, cam follower wheel 235b, special-purpose brake rocker arm 210b and braking valve clearance adjusting screw 110b.Valve clearance adjusting screw 110b is fixed on the dedicated rocker arm 210b by lock nut 105b.Can be with under the valve clearance adjusting screw 110b and resemble foot pad 114b.Brake cam 230b has a small embossment part at least on interior basic circle 225b, be used for engine braking.Present embodiment uses two

small embossment parts

232 and 233, is respectively applied for compression and discharges and exhaust gas recirculatioon.Be installed on the pitman arm shaft 205b special-purpose brake rocker arm 210b swing type, be biased in off position by spring 198b usually, just on the brake cam 230b.

Outlet valve system 300 contains an outlet valve at least, and this implements to have shown two

outlet valve

300a and 300b in the illustration.They are withstood on the valve seat 320 in the engine cylinder cover 500 by

valve spring

310a and 310b, control gaseous flowing between engine cylinder and outlet pipe 600.Usually, exhaust valve actuation device 200 is delivered to

outlet valve

300a and 300b with the mechanical motion of the big convex portion 220 of cam 230, and it is is periodically opened and closed.During engine braking, the small embossment part 232 of

brake cam

230b and 233 mechanical motion by special valve actuator 200b, are delivered to outlet valve 300a by the brake piston that is in operating position, produce the compression-release braking.

The driving mechanism 100 of engine braking also comprises brake-operating system, is integrated in the drain tap system.The brake piston 160 of present embodiment is positioned at valve bridge 400, can slide between off position and operating position.Usually, brake piston 160 inwardly is biased in as shown in Figure 3A off position by brake spring 177, and not operation surface 145 is filled up between the 114b gap 132 is arranged with resembling foot, and with the spacing of operating surface 140 be 130.One end of spring 177 is on the snap ring of piston 160, and the other end is on spring seat 178.Spring seat 178 leans against on the locating stud 142 that is fixed in the valve bridge 400.One axial grooving is arranged on the hole of brake piston 160, and its width is slightly larger than pin locating stud 142 diameters.The combination of locating stud 142 and grooving forms a kind of limit movement mechanism and anti-rotation mechanism or guide mechanisms to brake piston 160.Also can come the rotation of control piston with compressing tablet.

When the needs engine braking, control mechanism 50 is opened (Fig. 2 A), and machine oil comprises passage 410 by engine braking fluid networking, enters the pressure chamber 425 (Fig. 3 A) in the valve bridge 400.Oil pressure overcomes the pretightening force of spring 177, and the brake piston 160 in the valve bridge opening 415 is extrapolated to operating position from off position, rests on the locating stud 142.Operating surface 140 has been moved to and has resembled under the foot pad 114b.Now, piston 160 reaches operating position fully, eliminates or has reduced gap 132 (Fig. 3 B).The

small boss

232 and 233 of brake cam 230b is produced moves through piston 160 and valve bridge 400 is delivered to outlet valve 300a, produces engine braking.

When normal engine operates or does not need engine braking, control mechanism 50 cuts out (Fig. 2 B), nos oil pressure or oil pressure are very low in the pressure chamber 425, and brake piston 160 is back into off position (Fig. 3 A) in the valve bridge opening 415 by spring 177, and brake dedicated rocker arm 210b (resembling sufficient 114b) and separate.Brake rocker arm 210b is biased on the brake cam 230b by spring 198b, separates with not operation on the valve bridge 400 surface 145, and

small boss

232 and 233 motion are skipped on the brake cam.At this moment, the driving mechanism 100 of engine brake is in off position, does not participate in the motor normal operation that is produced by exhaust cam 230.

Embodiment shown in Fig. 3 A and the 3B can be modified and change and not break away from scope of the present utility model and principle.For example, the operating surface 140 on the brake piston 160 can be the boss face of swelling from piston, and the not operation surface can move on on the valve bridge 400.In addition,

spring

198 and 198b can be without pressure springs, and with other spring, such as leaf spring or torsion spring.Also have, brake cam can use different camshaft (as crest places the cam) with exhaust cam, and brake rocker arm 210b also uses different pitman arm shafts with exhaust rocker arm 210 so.Certainly, brake cam and exhaust cam also can use same camshaft, and brake rocker arm 210b and exhaust rocker arm 210 also use same pitman arm shaft 205 so.At this moment, special-purpose brake rocker arm 210b and exhaust rocker arm 210 are placed on the same pitman arm shaft 205 abreast, and Fig. 3 A and 3B are a understandable expansion schematic representation, and as installed figure as shown in Figure 4.

Shown in Figure 5 is another kind of fuel system.Except top said braking oil duct or network, increased oil leab.Another oil duct 211p of machine oil in the pitman arm shaft 205 flows to the oil duct 214p in the rocking arm 210, resembles foot from the nozzle opening directive then, mainly is that the lubricated foot that resembles waits friction member when engine ignition.

Fig. 6 A and 6B provide other two kinds of brake piston structures.Fig. 6 A has used by nut 173 and has been fastened on spring guiding pole 175 on the valve bridge 400.One of spring 177 is fixed on the pole 175, and the other end then is fixed on the snap ring 176 that places in the brake piston 160.Usually, brake piston 160 is biased in the off position shown in Fig. 6 A by spring 177.Fig. 6 B directly is contained in spring 177 in the hole, valve bridge ground, does not need snap ring 176 and guiding pole 175, but has increased by one silently 171.In fact, other brake piston structure also can adopt, and does not enumerate one by one at this.

Fig. 7 is the schematic representation of second embodiment of engine braking apparatus of the present utility model in its off-position, is that with first embodiment's the main distinction braking drive organ and exhaust gas drive mechanism have integrated.The

braking usefulness boss

232 and 233 and exhaust boss 220 on same cam.Braking valve clearance adjusting screw 110b is fixed on the exhaust rocker arm 210 by nut 105b, can pass through brake piston 160 and valve bridge 400, acts directly on the outlet valve 300a below it.What brake piston 160 adopted is the structure shown in Fig. 6 A, when not braking, inwardly is biased in the valve bridge 400 by spring 177.At this moment, a gap 132 is arranged between cam 230 and the cam follower wheel 235,

braking boss

232 and 233 is skipped (Fig. 7).When the needs engine braking, control mechanism 50 is opened (Fig. 2 A), and machine oil enters valve bridge 400 by engine braking fluid networking.Oil pressure overcomes the pretightening force of spring 177, with brake piston 160 to extrapolation.When valve bridge 400 was deflated boss 220 and pushes, brake piston 160, rested on the locating stud 142 to being extrapolated to operating position from off position.Operating surface 140 has been moved under the adjusting screw 110b.Now, piston 160 reaches operating position fully, and when valve bridge 400 returned, brake piston 160 promoted rocking arm 210 inhours, eliminates gap 132.Braking

small boss

232 and 233 is produced moves through piston 160 and valve bridge 400 is delivered to outlet valve 300a, produces engine braking.

Above-mentioned explanation has comprised a lot of concrete mode of executions, and this should not be regarded as the restriction to the utility model scope, but as representative concrete illustrations more of the present utility model, many other differentiation all might therefrom produce.For instance, the engine braking apparatus of Xian Shiing not only can be used for overhead cam engine here, also can be used for push rod/tubular type motor.Spring 198 can be blade or other form, also can be installed in other place, as between push rod and the rocking arm etc.In addition, driving mechanism 100 can be integrated into the miscellaneous part of air valve system, as rocking arm; Also can control by other control mechanism, as the dedicated hydraulic system, common rail system, and pneumatic system.Also have, the braking bearing system of Xian Shiing also can be replaced by the casing that is installed on the motor here, is converted to the type braking of losing heart thereby will compress to discharge to brake.

Therefore, scope of the present utility model should not decided by above-mentioned concrete illustration, but is decided by affiliated claim and the suitable power of law thereof.

Claims

1 one kinds of rocking arm-valve bridge composite engine braking device are converted to engine braking running (10) with the motor normal operation (20) of internal-combustion engine, and described device contains:

1.1) driving mechanism (100), described driving mechanism (100) contains the braking bearing system that is installed on the motor and is integrated in the interior brake-operating system of engine exhaust valve system; Described brake-operating system comprises brake piston (160), and described brake piston (160) can move between off position (0) and operating position (1); In off position (0), brake piston (160) withdrawal, driving mechanism (100) and engine exhaust valve are that contained outlet valve (300a or 300) separates; In operating position (1), brake piston (160) stretches out, and driving mechanism (100) makes outlet valve (300a or 300) open, and produces described engine braking running (10); And

1.2) be used for control mechanism (50) that brake piston (160) is moved between off position (0) and operating position (1).

2. device as claimed in claim 1, it is characterized in that: described braking bearing system comprises special-purpose brake rocker arm (210b) and brake cam (230b), at least one small embossment part (232 or 233) is arranged on the brake cam (230b), be installed on the pitman arm shaft (205b) special-purpose brake rocker arm (210b) swing type, when brake piston (160) is in operating position (1), open outlet valve (300a or 300), produce described engine braking running.

3. device as claimed in claim 1 is characterized in that: described braking bearing system also comprises integrated rocking arm (210) and integrated cam (230), and integrated cam (230) contains exhaust boss (220) and braking boss (232 and 233).

4. as claim 1 or 2 or 3 described devices, it is characterized in that: described braking bearing system also comprises spring (198 or 198b), in order to described driving mechanism (100) is biased in off position.

5. as claim 1 or 2 or 3 described devices, it is characterized in that: described braking bearing system also comprises the valve clearance regulating system, in order to set the valve clearance (132) between driving mechanism (100) and the vent systems.

6. as claim 1 or 2 or 3 described devices, it is characterized in that: it is in the contained valve bridge (400) that the brake piston of described brake-operating system (160) is integrated in the engine exhaust valve, and is biased in off position (0) by brake spring (177).

7. as claim 1 or 2 or 3 described devices, it is characterized in that: described brake-operating system also comprises limit movement mechanism, in order to the stroke and the rotation of control brake piston.

8. as claim 1 or 2 or 3 described devices, it is characterized in that: described control mechanism (50) comprises the mechanical electronic hydraulic pressing system, described mechanical electronic hydraulic pressing system comprises solenoid valve (51), by the stream of the liquid in the brake fluid networking, the motion of control brake piston (160) between off position (0) and operating position (1).

9. device as claimed in claim 7, it is characterized in that: described limit movement mechanism is combined by the axial grooving and the locating stud (142) of brake piston (160), the width of described axial grooving is slightly larger than the diameter of locating stud (142), and the stroke of the length of axial grooving decision brake piston (160).

10. as claim 1 or 2 or 3 described devices, it is characterized in that: described driving mechanism (100) also comprises two oil ducts (214 and 214p).