EP3494292B1 - Hydraulic tappet - Google Patents
Hydraulic tappet Download PDFInfo
- Publication number
- EP3494292B1 EP3494292B1 EP17748576.0A EP17748576A EP3494292B1 EP 3494292 B1 EP3494292 B1 EP 3494292B1 EP 17748576 A EP17748576 A EP 17748576A EP 3494292 B1 EP3494292 B1 EP 3494292B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- plunger
- hydraulic tappet
- ball
- high pressure
- cavity
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000007789 sealing Methods 0.000 claims description 13
- 238000002485 combustion reaction Methods 0.000 claims description 7
- 238000003860 storage Methods 0.000 claims description 7
- 239000012530 fluid Substances 0.000 claims description 5
- 238000004891 communication Methods 0.000 claims description 4
- 230000009471 action Effects 0.000 description 7
- 230000008901 benefit Effects 0.000 description 6
- 238000003754 machining Methods 0.000 description 4
- 238000011084 recovery Methods 0.000 description 4
- 230000008878 coupling Effects 0.000 description 3
- 238000010168 coupling process Methods 0.000 description 3
- 238000005859 coupling reaction Methods 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 230000001050 lubricating effect Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
- F01L1/00—Valve-gear or valve arrangements, e.g. lift-valve gear
- F01L1/26—Valve-gear or valve arrangements, e.g. lift-valve gear characterised by the provision of two or more valves operated simultaneously by same transmitting-gear; peculiar to machines or engines with more than two lift-valves per cylinder
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
- F01L1/00—Valve-gear or valve arrangements, e.g. lift-valve gear
- F01L1/20—Adjusting or compensating clearance
- F01L1/22—Adjusting or compensating clearance automatically, e.g. mechanically
- F01L1/24—Adjusting or compensating clearance automatically, e.g. mechanically by fluid means, e.g. hydraulically
Definitions
- This invention relates to a hydraulic tappet.
- this invention relates to a hydraulic tappet comprising a bridge for actuating valves.
- hydraulic tappet normally means a tappet equipped with a hydraulic telescopic device, connected to the lubricating circuit of the motor, which, with its travel, is able to automatically recover the clearance existing between the tappet and the valves actuated by it.
- the above-mentioned clearance is to be considered the result of multiple components such as, for example, machining tolerances, thermal expansion and wear of parts after their normal use.
- It is basically plungers integrated in telescopic hydraulic means.
- hydraulic telescopic elements of known type are in the form of an assembled cartridge which comprises an outer jacket and an inner plunger engaged slidably with each other.
- valve unit integral n movement with the plunger.
- the aim of this invention is provide a hydraulic tappet which is able to overcome the drawbacks of the prior art and which is at same time inexpensive to make, practical to operate and simple to install.
- the reference numeral 1 denotes their its entirety parts of a hydraulic tappet for an internal combustion engine (not illustrated), made in accordance with this invention.
- the tappet 1 comprises a bridge 2 configured for controlling the movement of two valves, not illustrated, the bridge 2 being actuated in known manner by a rocker, also not illustrated.
- the bridge 2 has a central portion 2c and two side arms 2a, 2b extending on both sides from the central portion 2c and designed to engage with respective rods, not illustrated, of respective valves.
- valves engage in respective holes 3 made in the respective lower faces of the two arms 2a, 2b of the bridge 2.
- the bridge 2 has, at its above-mentioned central portion 2c, a blind cylindrical cavity 4 having an inner wall 4a, a bottom wall 4f and an upper outlet 5.
- the hydraulic tappet 1 comprises a device 6 for recovering the clearance between the tappet and the valves (one or more), not illustrated, actuated by it.
- the device 6 for recovering the clearance between the tappet and one or more valves, not illustrated, actuated by it.
- the device 6 for recovering the clearance comprises a plunger 7 slidably engaged inside the above-mentioned cavity 4 and emerging from it partially at the relative upper outlet 5.
- the plunger 7 comprises a central body 8 and an upper cover 9.
- the tank 10 is advantageously cylindrical in shape.
- the tank 10 is covered by the above-mentioned cover 9 applied at the top, towards the outside.
- the cover 9 is fixed to the central body 8 by the interposition of an elastic ring 9a occupying at least partly two circumferential hollows made respectively on the cover 9 and on the body 8 and facing each other.
- the upper cover 9 is designed to engage, with known methods and not illustrated nor further described hereafter, with other tappet elements 1, such as a rocker, for example by a pushing element of the so-called bell-bottom type.
- the cover 9 advantageously has a diameter greater than the diameter of the above-mentioned upper outlet 5 of the cylindrical cavity 4, to limit with a shape impediment the stroke of the plunger 7 inside the cylindrical cavity 4.
- the device 6 for recovery of the clearance comprises, supported by the central body 8 of the plunger 7, the check valve means 11 for adjusting a flow of oil circulating inside the cavity 4.
- the device 6 for recovery comprises a first helical spring M1 interposed between the bottom wall 4f of the cylindrical cavity 4 and the central body 8 of the plunger 7.
- the first spring M1 is designed to oppose the movement of the plunger 7 inside the cylindrical cavity 4 towards the relative bottom wall 4f.
- a high pressure chamber 12 which has a variable volume as a function of the sliding of the cylindrical plunger 7 inside the cavity 4.
- the chamber 12 is defined by high pressure since the oil in it reaches maximum pressure values due to the compression action to which it is subjected in use.
- a connecting conduit 13 configured to place the tank 10 in fluid communication with the above-mentioned high pressure chamber 12.
- the above-mentioned valve means 11 comprise a ball 14 for retaining the oil interposed between the oil storage tank 10 and the high pressure chamber 12, the ball 14 being designed to close the connecting conduit 13 preventing the circulation of oil inside it.
- the ball 14 is housed inside a respective housing 15 made in the central body 8 of the plunger 7.
- the valve means 11 also comprise a second spring M2 interposed between the connecting conduit 13 and the ball 14, the second spring M2 acting on the ball 14, on the opposite side to the plate 16, to keep it normally moved away from the conduit 13 at least until the pressure of the oil inside the high pressure chamber 12 reaches a predetermined value such as to overcome the force applied by the second spring M2.
- the second spring M2 is housed inside a bushing 17 facing above the oil storage tank 10, the bushing 17 forming, with a respective central hole, the above-mentioned connecting conduit 13.
- the ball 14 is designed to obstruct the conduit 13 preventing the passage of oil from the high pressure chamber 12 towards the storage tank 10.
- the plunger 7 has a bottom portion 7a with a smaller diametric size, that is to say, less than the remaining upper portion which slidably engages on the inner cylindrical wall 4a of the cavity 4.
- the plunger 7 houses and supports an annular sealing element 18 mounted on it externally and designed to guarantee the dynamic seal between the plunger 7 and the inner wall 4a of the cavity 4 during the sliding of the plunger 7 along the cavity 4.
- annular sealing unit 18 is of the self-energising type.
- the oil inside the high pressure chamber 12 flows inside the gap 12a and applies on the annular sealing unit 18 a radial force towards the outside, pushing it against the inner wall 4a of the cavity 4.
- the containment plate 16 is advantageously shaped in the form of a cup and has a circumferential edge 19 configured to move towards the underside of the above-mentioned annular sealing element 18 with a relative upper face 19a.
- the above-mentioned first spring M1 has a relative upper end, consisting basically of a first coil, located in contact with a lower face 19b of the circumferential edge 19.
- the variability of the volume of the high pressure chamber 12, consequent to the sliding of the plunger 7 along the cavity 4 according to the direction of the axis A advantageously allows the recovery of any clearance existing between the tappet 1 and the valves, not illustrated, of the internal combustion engine.
- a connecting conduit 13 configured to place them in fluid communication with each other.
- the above-mentioned ball 14 is located along the above-mentioned connecting conduit 13 and is designed to obstruct it, under certain operating conditions, that is to say, when the pressure of the oil in the chamber 12 becomes such as to exceed the opposing elastic action exerted on the ball 14 by the second helical spring M2.
- the ball 14 is designed to close the connecting conduit 13 when the pressure in the high pressure chamber 12 is greater than that existing in the tank 10, the second spring helical M2 performing basically the function of keeping the ball 14 in a position such as not to obstruct the conduit 13 when the pressure in the tank 10 is greater than or equal to the pressure in the high pressure chamber 12.
- the spring M2 is configured in such a way as to delay the closing of the check valve units 11, to allow the plunger 7 to move along the cavity 4 to compensate for any wear and thermal expansion.
- the pushing action exerted by the other elements, not illustrated, of the tappet 1 on the cover 9 determine a simultaneous pushing downwards on the plunger 7 which, if it were not for the closing of the conduit 13 by the ball 14, could lead to a lowering of the plunger.
- the pressure of the oil inside the chamber 12 increases rapidly until a stopping the relative movement between plunger 7 and bridge 2, thereby improving the effect of transmitting the thrust to the underlying valves.
- the oil inside the high pressure chamber 12 flows around the annular sealing unit 18, in particular inside the gap 12a, and acts on it by applying forces axially upwards and radially outwards, pushing it against the inner wall 4a of the cavity 4.
- a first advantage provided by the tappet 1 according to this invention is due to the fact that the plunger 7 is slidable directly on the through cavity 4 made on the bridge, without requiring the presence of any containment jacket as in prior art solutions.
- the annular sealing unit 18 a particularly precise machining tolerance (which is costly to achieve) for the inner wall 4a of the cavity 4 is not even necessary, because the unit 18 can compensate for any imprecisions in the coupling with the plunger 7.
- the making of the through cavity 4 is therefore particularly inexpensive, as it is performed by boring fully in the central portion 2c of the bridge 2 and does not even require, as mentioned, a machining tolerance which is particularly precise, resulting in less costly machining that would be required in the absence of the annular sealing unit 18.
- Another advantage resulting from this invention is due to the limitation of the number of components of the tappet: sliding the plunger 7 directly on the inner wall 4a of the cavity 4 means that no additional jacket is in fact required.
- a greater surface of the high pressure chamber 12 implies small pressures on the components with the same force.
- a direct consequence of this circumstance is less stress on the components, such as, for example, the valve units 11 or the annular sealing unit 18 which will also be subjected to less wear.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Valve-Gear Or Valve Arrangements (AREA)
- Lubricants (AREA)
Description
- This invention relates to a hydraulic tappet.
- More specifically, this invention relates to a hydraulic tappet comprising a bridge for actuating valves.
- The expression hydraulic tappet normally means a tappet equipped with a hydraulic telescopic device, connected to the lubricating circuit of the motor, which, with its travel, is able to automatically recover the clearance existing between the tappet and the valves actuated by it.
- The above-mentioned clearance is to be considered the result of multiple components such as, for example, machining tolerances, thermal expansion and wear of parts after their normal use.
- In the distribution systems, which control through the valves the fluid flow into and out from the cylinders of the internal combustion engine, prior art teaches the use of plungers mounted on rockers or on bridges to reduce the clearance between the valves and the components designed for their actuation.
- It is basically plungers integrated in telescopic hydraulic means.
- These hydraulic telescopic elements of known type are in the form of an assembled cartridge which comprises an outer jacket and an inner plunger engaged slidably with each other.
- There is also a valve unit integral n movement with the plunger.
- These prior art solutions, even though operatively effective, have been seen to not be free from drawbacks.
- Especially in the assembly on a bridge, as a result of the dimensional limitations imposed by this architecture, these prior art solutions do not allow an easy installation, also requiring an increase in size of the bridge itself Known plungers and telescopic elements are disclosed in
WO 2009/143337 A1 andUS 5622147 A . - Moreover, the sliding between the jacket and the plunger, which must occur substantially in a sealed fashion, requires the production of a coupling between the two with extremely fine tolerances, thus implying high costs for making these elements.
- This drawback is also found with telescopic elements of the type not with a cartridge, where a sliding surface is formed directly in the bridge body as described in
US patent 8210144 . - The aim of this invention is provide a hydraulic tappet which is able to overcome the drawbacks of the prior art and which is at same time inexpensive to make, practical to operate and simple to install.
- The technical features of the invention, with reference to the above aims, are clearly described in the appended claims and its advantages are more apparent from the detailed description which follows, with reference to the accompanying drawings which illustrate preferred, non-limiting example embodiments of it, and in which:
-
Figure 1 is a schematic side elevation view, with some parts in cross-section and others cut away, of a preferred embodiment of the hinge according to this invention; -
Figure 2 shows a scaled-up detail of the tappet ofFigure 1 . - As illustrated in the accompanying drawings, the reference numeral 1 denotes their its entirety parts of a hydraulic tappet for an internal combustion engine (not illustrated), made in accordance with this invention.
- The tappet 1 comprises a
bridge 2 configured for controlling the movement of two valves, not illustrated, thebridge 2 being actuated in known manner by a rocker, also not illustrated. - The
bridge 2 has acentral portion 2c and twoside arms central portion 2c and designed to engage with respective rods, not illustrated, of respective valves. - More in detail, the above-mentioned and not illustrated valves engage in
respective holes 3 made in the respective lower faces of the twoarms bridge 2. - With reference to
Figures 1 and2 , thebridge 2 has, at its above-mentionedcentral portion 2c, a blindcylindrical cavity 4 having aninner wall 4a, abottom wall 4f and anupper outlet 5. - The
cylindrical cavity 4 has a central axis A. - The hydraulic tappet 1 comprises a
device 6 for recovering the clearance between the tappet and the valves (one or more), not illustrated, actuated by it. - As clearly illustrated in the accompanying drawings, inside the above-mentioned through
cavity 4 is housed thedevice 6 for recovering the clearance between the tappet and one or more valves, not illustrated, actuated by it. - The
device 6 for recovering the clearance comprises aplunger 7 slidably engaged inside the above-mentionedcavity 4 and emerging from it partially at the relativeupper outlet 5. - The
plunger 7 comprises acentral body 8 and anupper cover 9. - Inside the
main body 8 of theplunger 7, in a suitable recess, is formed a space defining anoil storage tank 10. - The
tank 10 is advantageously cylindrical in shape. - The
tank 10 is covered by the above-mentionedcover 9 applied at the top, towards the outside. - Advantageously, the
cover 9 is fixed to thecentral body 8 by the interposition of anelastic ring 9a occupying at least partly two circumferential hollows made respectively on thecover 9 and on thebody 8 and facing each other. - The
upper cover 9 is designed to engage, with known methods and not illustrated nor further described hereafter, with other tappet elements 1, such as a rocker, for example by a pushing element of the so-called bell-bottom type. - The
cover 9 advantageously has a diameter greater than the diameter of the above-mentionedupper outlet 5 of thecylindrical cavity 4, to limit with a shape impediment the stroke of theplunger 7 inside thecylindrical cavity 4. - The
device 6 for recovery of the clearance comprises, supported by thecentral body 8 of theplunger 7, the check valve means 11 for adjusting a flow of oil circulating inside thecavity 4. - The
device 6 for recovery comprises a first helical spring M1 interposed between thebottom wall 4f of thecylindrical cavity 4 and thecentral body 8 of theplunger 7. - The first spring M1 is designed to oppose the movement of the
plunger 7 inside thecylindrical cavity 4 towards therelative bottom wall 4f. - At the above-mentioned 4f bottom wall of the
cylindrical cavity 4 there is, for the hydraulic tappet 1, ahigh pressure chamber 12, which has a variable volume as a function of the sliding of thecylindrical plunger 7 inside thecavity 4. - The
chamber 12 is defined by high pressure since the oil in it reaches maximum pressure values due to the compression action to which it is subjected in use. - Inside the
central body 8 of theplunger 7 there is also formed a connectingconduit 13 configured to place thetank 10 in fluid communication with the above-mentionedhigh pressure chamber 12. The above-mentioned valve means 11 comprise aball 14 for retaining the oil interposed between theoil storage tank 10 and thehigh pressure chamber 12, theball 14 being designed to close the connectingconduit 13 preventing the circulation of oil inside it. - The
ball 14 is housed inside arespective housing 15 made in thecentral body 8 of theplunger 7. - The tappet 1 also comprises, positioned below the above-mentioned housing 15 a
plate 16 for containing theball 14 inside thehousing 15. - The valve means 11 also comprise a second spring M2 interposed between the connecting
conduit 13 and theball 14, the second spring M2 acting on theball 14, on the opposite side to theplate 16, to keep it normally moved away from theconduit 13 at least until the pressure of the oil inside thehigh pressure chamber 12 reaches a predetermined value such as to overcome the force applied by the second spring M2. - In other words, the second helical spring M2 is designed to apply a relative elastic action against the
ball 14, for pushing the latter away from thetank 10. - The second spring M2 is housed inside a
bushing 17 facing above theoil storage tank 10, the bushing 17 forming, with a respective central hole, the above-mentioned connectingconduit 13. - More in detail, with reference to
Figure 2 , theball 14 is designed to obstruct theconduit 13 preventing the passage of oil from thehigh pressure chamber 12 towards thestorage tank 10. - As illustrated in detail in
Figure 2 , theplunger 7 has abottom portion 7a with a smaller diametric size, that is to say, less than the remaining upper portion which slidably engages on the innercylindrical wall 4a of thecavity 4. - At the relative above-mentioned
lower portion 7a theplunger 7 houses and supports anannular sealing element 18 mounted on it externally and designed to guarantee the dynamic seal between theplunger 7 and theinner wall 4a of thecavity 4 during the sliding of theplunger 7 along thecavity 4. - Between the
lower portion 7a andannular unit 18 there is anannular gap 12a inside of which the oil present in thehigh pressure chamber 12 flows. Advantageously, theannular sealing unit 18 is of the self-energising type. As described in more detail below, the oil inside thehigh pressure chamber 12 flows inside thegap 12a and applies on the annular sealing unit 18 a radial force towards the outside, pushing it against theinner wall 4a of thecavity 4. As shown inFigure 2 , thecontainment plate 16 is advantageously shaped in the form of a cup and has acircumferential edge 19 configured to move towards the underside of the above-mentionedannular sealing element 18 with a relativeupper face 19a. - Again with reference to
Figure 2 , the above-mentioned first spring M1 has a relative upper end, consisting basically of a first coil, located in contact with alower face 19b of thecircumferential edge 19. - In use, the variability of the volume of the
high pressure chamber 12, consequent to the sliding of theplunger 7 along thecavity 4 according to the direction of the axis A, advantageously allows the recovery of any clearance existing between the tappet 1 and the valves, not illustrated, of the internal combustion engine. - As mentioned, between the
oil storage tank 10 and thehigh pressure chamber 12 there is a connectingconduit 13, configured to place them in fluid communication with each other. - The above-mentioned
ball 14 is located along the above-mentioned connectingconduit 13 and is designed to obstruct it, under certain operating conditions, that is to say, when the pressure of the oil in thechamber 12 becomes such as to exceed the opposing elastic action exerted on theball 14 by the second helical spring M2. - In other words, the
ball 14 is designed to close the connectingconduit 13 when the pressure in thehigh pressure chamber 12 is greater than that existing in thetank 10, the second spring helical M2 performing basically the function of keeping theball 14 in a position such as not to obstruct theconduit 13 when the pressure in thetank 10 is greater than or equal to the pressure in thehigh pressure chamber 12. - The spring M2 is configured in such a way as to delay the closing of the
check valve units 11, to allow theplunger 7 to move along thecavity 4 to compensate for any wear and thermal expansion. - During the normal operation of the internal combustion engine in which the tappet 1 is integrated, oil is fed inside the
high pressure chamber 12; following this oil flow, thechamber 12 increases its volume and theplunger 7 is pushed to move away from thebottom wall 4f of thecavity 4, facilitated also by the elastic action of the first spring M1, until eliminating any clearances existing between thebridge 2 and the other elements of the internal combustion engine with which thebridge 2 operates in conjunction. - After eliminating these clearances, the pushing action exerted by the other elements, not illustrated, of the tappet 1 on the
cover 9 determine a simultaneous pushing downwards on theplunger 7 which, if it were not for the closing of theconduit 13 by theball 14, could lead to a lowering of the plunger. However, thanks to the closing of the connecting conduit 13 (due basically to the action of the fluid friction force on theball 14 by the oil present in the housing 15), the pressure of the oil inside thechamber 12 increases rapidly until a stopping the relative movement betweenplunger 7 andbridge 2, thereby improving the effect of transmitting the thrust to the underlying valves. - At the same time, the oil inside the
high pressure chamber 12 flows around theannular sealing unit 18, in particular inside thegap 12a, and acts on it by applying forces axially upwards and radially outwards, pushing it against theinner wall 4a of thecavity 4. - The closing action against the
inner wall 4a, together with the closing of theconduit 13 described above prevents the flow of oil outside thehigh pressure chamber 12. - The invention described above achieves the preset aims and brings important advantages.
- A first advantage provided by the tappet 1 according to this invention is due to the fact that the
plunger 7 is slidable directly on the throughcavity 4 made on the bridge, without requiring the presence of any containment jacket as in prior art solutions. - This circumstance, that is to say, the use of the
inner wall 4a of thecavity 4 as the sliding surface of theplunger 7, is permitted by the adoption of the dynamicannular sealing unit 18, thanks to which this sliding occurs in a sealed fashion. - Moreover, thanks to the presence of the
annular sealing unit 18, a particularly precise machining tolerance (which is costly to achieve) for theinner wall 4a of thecavity 4 is not even necessary, because theunit 18 can compensate for any imprecisions in the coupling with theplunger 7. The making of the throughcavity 4 is therefore particularly inexpensive, as it is performed by boring fully in thecentral portion 2c of thebridge 2 and does not even require, as mentioned, a machining tolerance which is particularly precise, resulting in less costly machining that would be required in the absence of theannular sealing unit 18. - In this regard, the circumstance described constitutes a considerable advantage also due to the problems notoriously widespread in the trade. The extreme precision required in the couplings has in fact forced the manufacturers of the prior art devices to resort to the so-called "select fit" procedure which consists in measuring before assembly all the components produced, dividing them into tolerance classes (that is, groups with similar micrometric measurements), and then assembling the components selected from compatible tolerance classes.
- This articulated process is overcome advantageously by the solution according to the invention.
- Another advantage resulting from this invention is due to the limitation of the number of components of the tappet: sliding the
plunger 7 directly on theinner wall 4a of thecavity 4 means that no additional jacket is in fact required. - The absence of the jacket results in a further advantage: a greater surface area of the
high pressure chamber 12 which may in fact extending diametrically to theinner wall 4a of thecavity 4. - A greater surface of the
high pressure chamber 12 implies small pressures on the components with the same force. - In other words, since the surface of the
high pressure chamber 12 is greater, the force transmitted by therocker 2 to the valves will result in less pressure inside thechamber 12. - A direct consequence of this circumstance is less stress on the components, such as, for example, the
valve units 11 or theannular sealing unit 18 which will also be subjected to less wear. - From another viewpoint, the circumstance described above also makes it possible, with an equal surface area of the high pressure chamber, to have overall dimensions less than there would be with a hydraulic telescopic unit of known type with an assembled cartridge (due to the presence, precisely, of the jacket outside the plunger). This reduced size translates into a smaller dimension required for the bridge on which the clearance recovery device is installed, with consequent reduction in weight and cost of the bridge, which may also be more easily integrated in an existing system.
Claims (11)
- A hydraulic tappet of an internal combustion engine, comprising:- a bridge (2) configured to control the movement of two valves and having a central portion (2c) and two side arms (2a, 2b) designed to engage with respective rods of respective valves, the bridge (2) having at the central portion (2c) a blind cylindrical cavity (4) having an inner wall (4a), a bottom wall (4f) and a upper outlet (6);- a plunger (7) slidably engaged in the cavity (4) and emerging from it at least partially at the relative upper outlet (6), the plunger (7) being configured to engage at the top with a respective pushing element of the tappet;- a first spring (M1) interposed between the plunger (7) and the bottom wall (4f) of the cylindrical cavity (4) and designed to oppose the movement of the plunger (7) inside the cylindrical cavity (4) towards the relative bottom wall (4f);- retaining valve means (11) designed for adjusting a flow of oil circulating inside the cavity (4) characterized in that it further comprises- an annular sealing unit (18) integral with the plunger (7) and designed to guarantee the dynamic seal between the plunger (7) and the inner wall (4a) of the cavity (4) during the sliding of the plunger (7).
- The hydraulic tappet according to claim 1, wherein at the bottom wall (4f) of the cylindrical cavity (4) there is a high pressure chamber (12), the chamber (12) having variable volume as a function of the sliding of the plunger (7), characterised in that it comprises an oil storage tank (10) formed in the plunger (7) and a connecting conduit (13) configured in such a way as to put the tank (10) in fluid communication with the high pressure chamber (12).
- The hydraulic tappet according to claim 2, wherein the plunger (7) has a lower portion (7a) with a reduced diameter for housing the annular sealing unit (18), characterised in that it has an annular gap (12a) between the lower portion (7a) and the annular sealing unit (18), the gap being in communication with the high pressure chamber (12).
- The hydraulic tappet according to claim 2 or 3, characterised in that the valve means (10) comprise a retaining ball (14) interposed between the storage tank (10) and the high pressure chamber (12), the ball (14) being designed to close the connecting conduit (13).
- The hydraulic tappet according to claim 4, characterised in that the valve means (11) comprise a second spring valve (M2) interposed between the connecting conduit (13) and the ball (14), acting on the ball (14) to keep it moved away from the conduit (13) at least until the pressure of the oil inside the high pressure chamber (12) reaches a given value such as to overcome the force exerted by the second spring (M2).
- The hydraulic tappet according to claim 4 or 5, wherein the ball (14) is housed inside a respective housing (15) formed in the plunger (7), characterised in that underneath it comprises a plate (16) for containing the ball (14).
- The hydraulic tappet according to claim 6, characterised in that the containment plate (16) is cup-shaped and has a circumferential edge (19) configured to move towards the annular sealing element (18) with a relative upper face (19a).
- The hydraulic tappet according to claim 7, characterised in that the first spring (M1) has a relative upper end located in contact with a lower face (19b) of the circumferential edge (19).
- The hydraulic tappet according to any one of claims 2 to 8, characterised in that the plunger (7) comprises a cover (9) of the tank (10), configured for engaging at the top with a respective pushing element of the tappet.
- The hydraulic tappet according to claim 9, characterised in that the cover (9) has a diameter larger than the diameter of the upper outlet (7) of the cylindrical cavity (4), to limit the stroke of the plunger (7) inside the cylindrical cavity (4).
- An internal combustion engine comprising a plurality of hydraulic tappets according to any one of claims 1 to 10.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
IT102016000083177A IT201600083177A1 (en) | 2016-08-05 | 2016-08-05 | HYDRAULIC PUNTER. |
PCT/IB2017/054645 WO2018025152A1 (en) | 2016-08-05 | 2017-07-31 | Hydraulic tappet |
Publications (2)
Publication Number | Publication Date |
---|---|
EP3494292A1 EP3494292A1 (en) | 2019-06-12 |
EP3494292B1 true EP3494292B1 (en) | 2021-02-17 |
Family
ID=58159291
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP17748576.0A Active EP3494292B1 (en) | 2016-08-05 | 2017-07-31 | Hydraulic tappet |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP3494292B1 (en) |
CN (1) | CN109790765B (en) |
IT (1) | IT201600083177A1 (en) |
WO (1) | WO2018025152A1 (en) |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN110295960B (en) * | 2018-03-21 | 2020-10-30 | 潍柴动力股份有限公司 | Hydraulic control unit, valve bridge and engine |
CN110295961B (en) * | 2018-03-21 | 2020-09-29 | 潍柴动力股份有限公司 | Valve bridge and four-valve engine |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5622147A (en) * | 1996-03-08 | 1997-04-22 | Eaton Corporation | Hydraulic lash adjuster |
US5758613A (en) * | 1997-01-30 | 1998-06-02 | Eaton Corporation | Hydraulic lash adjuster and biased normally open check valve system therefor |
US8210144B2 (en) * | 2008-05-21 | 2012-07-03 | Caterpillar Inc. | Valve bridge having a centrally positioned hydraulic lash adjuster |
DE102008039504A1 (en) * | 2008-08-23 | 2010-02-25 | Schaeffler Kg | Four-stroke internal combustion engine, has crankcase and cylinder, where one transmission element or hydraulic valve-play compensating element is attached in component inserted in transmission element |
CN205330755U (en) * | 2016-02-04 | 2016-06-22 | 杭州新坐标科技股份有限公司 | Column formula hydraulic tappet who does not have spacing jump ring |
-
2016
- 2016-08-05 IT IT102016000083177A patent/IT201600083177A1/en unknown
-
2017
- 2017-07-31 WO PCT/IB2017/054645 patent/WO2018025152A1/en unknown
- 2017-07-31 CN CN201780059826.7A patent/CN109790765B/en active Active
- 2017-07-31 EP EP17748576.0A patent/EP3494292B1/en active Active
Non-Patent Citations (1)
Title |
---|
None * |
Also Published As
Publication number | Publication date |
---|---|
EP3494292A1 (en) | 2019-06-12 |
CN109790765B (en) | 2022-01-14 |
IT201600083177A1 (en) | 2018-02-05 |
WO2018025152A1 (en) | 2018-02-08 |
CN109790765A (en) | 2019-05-21 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP2310726B1 (en) | Pressure relief valve | |
KR101850337B1 (en) | Shock absorber | |
EP1298287B1 (en) | Hydraulic lash adjuster & Biased normally open check valve system therefor | |
EP2884135A1 (en) | Thermoregulator and thermoregulator component | |
EP3494292B1 (en) | Hydraulic tappet | |
EP2183468B1 (en) | Hydraulic lash compensation device with mechanical lift loss feature | |
EP3494291B1 (en) | Hydraulic tappet | |
KR102108964B1 (en) | Thermostatic valve | |
EP0267631B1 (en) | Self-contained hydraulic bucket lifter | |
CN115539164A (en) | Lost motion variable valve actuation system and method | |
US4311437A (en) | Radial piston pump | |
EP2206633B1 (en) | Two-stage slave cylinder | |
US20220049783A1 (en) | Valve, Method for Producing a Valve, and Device for Regulating the Pressure of a Fluid in a Vehicle Transmission, Comprising a Valve Designed as a Pressure Compensation Valve | |
US2908260A (en) | Hydraulic tappets | |
US4688526A (en) | Self-contained hydraulic bucket lifter | |
EP0953734A1 (en) | Hydraulic lash adjuster and check valve opening arrangement therefor | |
US3014472A (en) | Hydraulic valve tappet | |
EP2771553B1 (en) | Thermoregulator | |
US6536391B2 (en) | Compact hydraulic lash adjuster | |
JPS6261470B2 (en) | ||
JP7250144B2 (en) | Engine valve mechanism parts that selectively reset lost motion | |
JP7296268B2 (en) | damping force adjustable shock absorber | |
CN108930777B (en) | Temperature regulating valve | |
US10233795B2 (en) | Bypass valve for pressure oscillation control | |
CN108266242B (en) | Automatic valve clearance compensator for valve mechanism |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: UNKNOWN |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE |
|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE |
|
17P | Request for examination filed |
Effective date: 20190213 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR |
|
AX | Request for extension of the european patent |
Extension state: BA ME |
|
DAV | Request for validation of the european patent (deleted) | ||
DAX | Request for extension of the european patent (deleted) | ||
GRAP | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOSNIGR1 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: GRANT OF PATENT IS INTENDED |
|
INTG | Intention to grant announced |
Effective date: 20200929 |
|
GRAS | Grant fee paid |
Free format text: ORIGINAL CODE: EPIDOSNIGR3 |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE PATENT HAS BEEN GRANTED |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR |
|
REG | Reference to a national code |
Ref country code: GB Ref legal event code: FG4D |
|
REG | Reference to a national code |
Ref country code: CH Ref legal event code: EP |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R096 Ref document number: 602017032721 Country of ref document: DE |
|
REG | Reference to a national code |
Ref country code: AT Ref legal event code: REF Ref document number: 1361753 Country of ref document: AT Kind code of ref document: T Effective date: 20210315 |
|
REG | Reference to a national code |
Ref country code: IE Ref legal event code: FG4D |
|
REG | Reference to a national code |
Ref country code: SE Ref legal event code: TRGR |
|
REG | Reference to a national code |
Ref country code: LT Ref legal event code: MG9D |
|
REG | Reference to a national code |
Ref country code: NL Ref legal event code: MP Effective date: 20210217 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: PT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210617 Ref country code: NO Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210517 Ref country code: GR Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210518 Ref country code: FI Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210217 Ref country code: HR Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210217 Ref country code: LT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210217 Ref country code: BG Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210517 |
|
REG | Reference to a national code |
Ref country code: AT Ref legal event code: MK05 Ref document number: 1361753 Country of ref document: AT Kind code of ref document: T Effective date: 20210217 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: NL Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210217 Ref country code: LV Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210217 Ref country code: PL Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210217 Ref country code: RS Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210217 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IS Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210617 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: EE Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210217 Ref country code: CZ Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210217 Ref country code: AT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210217 Ref country code: SM Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210217 |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R097 Ref document number: 602017032721 Country of ref document: DE |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: SK Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210217 Ref country code: DK Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210217 Ref country code: RO Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210217 |
|
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
26N | No opposition filed |
Effective date: 20211118 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: ES Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210217 Ref country code: AL Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210217 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: SI Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210217 |
|
REG | Reference to a national code |
Ref country code: CH Ref legal event code: PL |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: MC Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210217 |
|
REG | Reference to a national code |
Ref country code: BE Ref legal event code: MM Effective date: 20210731 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: LI Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210731 Ref country code: CH Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210731 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IS Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210617 Ref country code: LU Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210731 Ref country code: FR Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210731 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210731 Ref country code: BE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210731 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: CY Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210217 |
|
P01 | Opt-out of the competence of the unified patent court (upc) registered |
Effective date: 20230526 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: HU Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT; INVALID AB INITIO Effective date: 20170731 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: IT Payment date: 20230720 Year of fee payment: 7 Ref country code: GB Payment date: 20230725 Year of fee payment: 7 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: SE Payment date: 20230726 Year of fee payment: 7 Ref country code: DE Payment date: 20230726 Year of fee payment: 7 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: MK Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210217 |