KR102251417B1 - Valve stem seal and internal combustion engine valve with the same - Google Patents

Abstract

Disclosed are a valve stem seal and an internal combustion engine valve having the same. The disclosed valve stem seal comprises: a rigid frame for surrounding an upper end of a valve guide, and fixedly supported by the valve guide; and an oil injector disposed above the valve guide inside the rigid frame, and supported by the rigid frame. The oil injector has an injector housing having an oil inlet hole formed on an upper side surface and an oil outlet hole formed on a lower side surface; and an oil pumping member installed to be lifted in an internal space of the injector housing, and attracted to a magnetic force of a permanent magnet to be lifted in synchronization with the elevation of the valve stem. The internal space of the injector housing is divided into an upper space above the oil pumping member and a lower space below the oil pumping member. Also, when the valve stem ascends to ascend the oil pumping member, the upper space becomes narrow, and the lower space becomes wider as the upper space becomes narrower, and thus, lubricating oil is moved from the upper space to the lower space. In addition, when the valve stem descends to descend the oil pumping member, the lower space becomes narrow to be pressurized so as to allow the lubricating oil of the lower space to be discharged between the valve stem and the valve guide through the oil outlet hole, and the upper space becomes wide as the lower space becomes narrow to allow the lubricating oil to be introduced into the upper space through the oil inlet hole. Accordingly, the durability of the valve stem is improved.

Description

Valve stem seal and internal combustion engine valve with the same

The present invention relates to a valve stem seal that controls a supply amount of lubricating oil for lubricating between a valve guide of an internal combustion engine and a valve stem, and an internal combustion engine valve having the same.

Piston reciprocating internal combustion engines mainly used as engines of vehicles have intake valves and exhaust valves that open when mixed gas is inhaled into the combustion chamber and when combustion gas is exhausted from the inside of the combustion chamber, and are closed when an explosion occurs inside the combustion chamber. Is installed. The intake valve and the exhaust valve are in common, a valve stem for lifting to open and close an intake port and an exhaust port, a valve guide for guiding the lifting motion of the valve stem, and the valve It has a valve stem seal that controls the inflow amount of lubricating oil flowing between the stem and the valve guide.

Lubricating oil is supplied between the valve stem and the valve guide through the valve stem seal outside the cylinder head of the internal combustion engine. If the supply amount of the lubricating oil is too large, the oversupplied lubricating oil passes between the valve stem and the valve guide and flows into the combustion chamber of the internal combustion engine, thereby deteriorating the performance of the internal combustion engine. Emissions are increased, and the cost for replacement and replenishment of lubricating oil increases. On the other hand, if the supply amount of the lubricating oil is too small, the wear of the valve stem is promoted, thereby deteriorating durability.

On the other hand, the conventional valve stem seal controls the supply amount of lubricating oil supplied between the valve stem and the valve guide only by the degree of wear of the rubber lip that elastically adheres to the valve stem regardless of the lifting speed of the valve stem. do. Therefore, there is also a problem in that the wear of the lip is accelerated and durability is lowered.

Registered Patent Publication No. 10-1196352

The present invention provides a valve stem seal in which an inflow amount of lubricating oil flowing between a valve stem and a valve guide from the outside of a cylinder head is controlled in proportion to the lifting speed of the valve stem, and an internal combustion engine valve having the same.

The present invention controls the inflow amount of lubricating oil flowing between a valve stem having a permanent magnet installed therein, and a valve guide that is fixed to the cylinder head and guides the elevation of the valve stem, and surrounds the upper end of the valve guide and the A rigid frame fixedly supported by the valve guide, and an oil injector disposed above the valve guide inside the rigid frame and supported by the rigid frame, wherein the oil injector includes oil on the upper side. An injector housing with an inlet hole formed and an oil outlet hole formed on the lower side, and installed to be elevating in the inner space of the injector housing, attracted by the magnetic force of the permanent magnet to move up and down in synchronization with the elevation of the valve stem And an oil pumping member, wherein the inner space of the injector housing is divided into an upper space above the oil pumping member and a lower space below the oil pumping member, and the valve stem rises to pump the oil. When the member rises, the upper space becomes narrower, and the lower space becomes wider as the upper space becomes narrower, and the lubricating oil moves from the upper space to the lower space, and when the valve stem descends and the oil pumping member descends, the As the lower space is narrowed and pressurized, the lubricating oil in the lower space is discharged between the valve stem and the valve guide through the oil outlet hole. Provides a valve stem seal through which lubricating oil flows into the space.

The oil injector may further include a check valve that opens the oil inlet hole when the oil pumping member descends and closes the oil inlet hole when the oil pumping member rises.

A fluid through hole may be formed in the oil pumping member so that lubricating oil can move between the upper space and the lower space.

Each of the upper space and the lower space may be filled with an oil absorber that absorbs lubricating oil, which is made of a foamed resin that is elastically contracted to restore volume.

The valve stem seal of the present invention is made of rubber, and further includes a sealing lip that is bonded and supported to the injector housing so as not to cover the oil inlet hole and extends elastically to the outer circumferential surface of the valve stem. I can.

The valve stem seal of the present invention further includes a rubber member made of rubber and bonded and supported on the inner circumferential surface of the rigid frame, wherein the rubber member is an oil bonded to the injector housing so that the injector housing is supported by the rigid frame. It may include an injector joint and a valve guide close contact with the outer circumferential surface of the upper end of the valve guide.

The rubber member may further include a spacer portion interposed between the injector housing and the valve guide without covering the oil outlet hole to separate the injector housing from the valve guide.

In addition, the present invention is to lift to open and close a port formed in a cylinder head of an internal combustion engine, a valve stem having a permanent magnet installed therein, a valve guide fixed to the cylinder head to guide the lift of the valve stem, and It provides an internal combustion engine valve having the above valve stem seal.

When the valve stem is raised and lowered, the permanent magnet may be raised or lowered between the height of the upper end and the lower end of the injector housing.

In the valve stem seal of the present invention, the lifting speed of the valve stem and the lifting speed of the oil pumping member are proportional. Accordingly, as the rotational speed (rpm) of the internal combustion engine which is proportional to the lifting speed of the valve stem increases, the amount of lubricating oil discharged from the oil injector and flowing into the gap between the valve stem and the valve guide increases. As a result, an appropriate amount of lubricating oil is introduced into the gap between the valve stem and the valve guide according to the rising/lowering speed of the valve stem, thus preventing damage to the valve stem or malfunctioning, and improving the durability of the valve stem. The emission of air pollutants contained in the exhaust gas is also reduced.

1 is a cross-sectional view showing an internal combustion engine valve according to an embodiment of the present invention.
2 is a cross-sectional view showing an enlarged portion II of FIG. 1.

Hereinafter, a valve stem seal and an internal combustion engine valve having the same according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. Terms used in the present specification are terms used to properly express preferred embodiments of the present invention, which may vary depending on the intention of a user or operator or customs in the field to which the present invention belongs. Therefore, definitions of these terms should be made based on the contents throughout the present specification.

1 is a cross-sectional view showing a valve of an internal combustion engine according to an embodiment of the present invention, and FIG. 2 is an enlarged cross-sectional view of part II of FIG. 1.

Referring to FIGS. 1 and 2 together, in a piston reciprocating internal combustion engine, an intake valve that is opened when the mixed gas is inhaled into the combustion chamber and when the combustion gas is exhausted from the inside of the combustion chamber to the outside, and is closed when an explosion occurs inside the combustion chamber. And an exhaust valve is installed. The internal combustion engine valve 10, such as the intake valve and the exhaust valve, is a valve stem 11 that lifts and descends to open and close a port 23 formed in a cylinder head 20 at the top of the cylinder. ), a pipe-shaped member press-fitting and fixed to the cylinder head 20, a valve guide 25 guiding the lifting motion of the valve stem 11, and the outer peripheral surface of the valve stem 11 And a valve stem seal 30 for controlling an inflow amount of lubricating oil flowing into the gap 28 between the outer circumferential surface of the valve guide 25 and the valve guide 25.

The valve stem 11 passes through the valve guide 25 and is fastened to the valve guide 25. A spring seat 17 is fixed to the upper end 12 of the valve stem 11, and between the spring seat 17 and the upper surface 21 of the cylinder head 20, a valve spring ( 24) is interposed. The valve stem 11 is elastically biased in an upward direction by the elastic force of the valve spring 24. A valve cam 18 is in contact with the upper end of the valve stem 11.

The diameter of the lower end 13 of the valve stem 11 is slightly larger than the inner diameter of the port 23. While the valve cam 18 rotates, at a specific rotation angle, the outer peripheral surface of the valve cam 18 presses the upper end of the valve stem 11 downward, so that the valve stem 11 descends and the port 23 opens, and the above At a rotation angle other than the specific rotation angle, the valve stem 11 is raised to its original position by the elastic restoring force of the valve spring 24, so that the lower end 13 of the valve stem 11 closes the port 23. A permanent magnet 15 is installed inside the valve stem 11.

The valve guide 25 is press-fitted and fixed to the cylinder head 20 so that its upper end 27 protrudes slightly higher than the height of the upper side 21 of the cylinder head 20. The valve stem seal 30 is tightly fixed to the upper end 27 of the valve guide 25 protruding higher than the upper side 21 of the cylinder head 20. The valve stem seal 30 includes a rigid frame 31, an oil injector 40, a sealing lip 60, and a rubber member 55.

The rigid frame 31 is formed of a material having high rigidity such as stainless steel, for example. The rigid frame 31 surrounds the upper end 27 of the valve guide 25 and is fixedly supported on the upper end 27 of the valve guide 25. The rigid frame 31 has a pipe portion having an inner diameter size surrounding the valve guide 25, and a flange portion extending radially with respect to the axis CL of the valve stem seal 30 at the lower end ( A flange portion) 34 is provided.

The lower end of the valve spring 24 for elastically pressing the valve stem 11 in the upward direction is supported on the flange portion 34. The upper end of the valve spring 24 is supported by the spring seat 17. Therefore, the valve spring 24 can be stably interposed between the cylinder head 20 and the spring seat 17, and damage to the upper side 21 or the bottom of the valve spring 24 of the cylinder head 20 is prevented. do.

The oil injector 40 is disposed above the valve guide 25 inside the pipe portion 32 of the rigid frame 31 and is supported by the pipe portion 32 of the rigid frame 31. The oil injector 40 has an injector housing 41, an oil pumping member 50, and a check valve 43. The injector housing 41 is an annular member surrounding the valve stem 11, and an inner space 47 in which lubricating oil is accommodated is provided therein. An oil inlet hole is formed on the upper side of the injector housing 41 so that lubricating oil flows into the injector housing 41 from the top of the injector housing 41, and the lubricating oil is provided on the lower side of the injector housing 41. ), an oil outlet hole 45 is formed so as to be discharged from the inside of the injector housing 41 to the bottom of the injector housing 41. Since a check valve 43 is installed in the oil inlet hole, a reference number corresponding to the oil inlet hole is not indicated in the drawing.

The oil inlet hole is disposed closer to the inner circumferential surface of the pipe part 32 among the outer circumferential surface of the valve stem 11 and the inner circumferential surface of the pipe part 32 of the rigid frame 31, and the oil outlet hole 45 is the valve stem ( 11) Among the outer circumferential surfaces and the inner circumferential surfaces of the pipe 32, are disposed closer to the outer circumferential surface of the valve stem 11. Although not clearly shown in FIG. 2, a plurality of oil inlet holes and oil outlet holes 45 are formed, respectively. The plurality of oil inlet holes and the plurality of oil outlet holes 45 are arranged at equiangular intervals along a circular orbit centered on the axis line CL. The check valve 43 is provided in a number corresponding to the number of oil inlet holes, so that one check valve 43 is installed for each oil inlet hole.

The oil pumping member 50 is an annular member installed in the inner space 47 of the injector housing 41 to be elevating and descending. All or at least a portion of the oil pumping member 50 is formed of, for example, a ferromagnetic material such as stainless steel or nickel. When the valve stem 11 moves up and down, the permanent magnet 15 installed on the valve stem 11 is also raised and lowered, and the oil pumping member 50 is also attracted by the magnetic force of the permanent magnet 15. ) To move up and down.

When the valve stem 11 is raised and lowered, the permanent magnet 15 moves up and down between the height of the top and the bottom of the injector housing 41, so that the installation height of the permanent magnet 15 and the top of the injector housing 41 And the height of the bottom is set. Accordingly, when the valve stem 11 is raised and lowered, the magnetic force of the permanent magnet 15 strongly affects the oil pumping member 50 so that the oil pumping member 50 is substantially the same height as the permanent magnet 15. Ascending and descending at approximately the same ascent speed.

The inner space 47 of the injector housing 41 is divided into two areas by the oil pumping member 50. That is, the inner space 47 is divided into a lower space 48 below the oil pumping member 50 and an upper space 49 above the oil pumping member 50. A fluid through hole 51 is formed in the oil pumping member 50 so that lubricating oil can be moved between the lower space 48 and the upper space 49.

The check valve is a valve that prevents reverse flow by allowing the fluid of the fluid to flow in only one direction and not in the opposite direction. The check valve 43 installed in the oil inlet hole opens the oil inlet hole when pressure is applied in the direction in which the lubricating oil flows from the outside of the injector housing 41 to the inside, and conversely, the check valve 43 is opened from the inside of the injector housing 41 to the outside. When pressure is applied in the direction in which the lubricating oil is discharged, the oil inlet hole is closed. In other words, when the oil pumping member 50 descends inside the injector housing 41, the check valve 43 opens the oil inlet hole, and conversely, when the oil pumping member 50 rises, the check valve ( 43) closes the oil inlet hole.

When the valve stem 11 rises during the reciprocating lifting motion, the oil pumping member 50 is raised by the magnetic force of the permanent magnet 15, so that the upper space 49 is narrowed, and the upper space 49 is narrowed. The lower space 48 is widened by the amount. As a result, the lubricating oil accommodated in the upper space 49 moves to the lower space 48 through the fluid through hole 51. At this time, since the oil inlet hole is closed by the check valve 43 as described above, the lubricating oil contained in the upper space 49 does not flow out of the injector housing 41 through the oil inlet hole. .

When the valve stem 11 descends during the reciprocating lifting motion, the oil pumping member 50 is lowered by the magnetic force of the permanent magnet 15, and the lower space 48 is compressed and compressed to the lower space 48. The received lubricating oil is discharged under the injector housing 41 through the oil outlet hole 45. The lubricating oil discharged through the oil outlet hole 45 flows into the gap 28 between the outer circumferential surface of the valve stem 11 and the inner circumferential surface of the valve guide 25 to lubricate the outer circumferential surface of the valve stem 11 that moves up and down. . Meanwhile, as described above, as the oil pumping member 50 descends, the check valve 43 opens the oil inlet hole, and the upper space 49 expands as the lower space 48 becomes narrower. Lubricating oil flows into the upper space 49 from the outside of the injector housing 41 through the inlet hole.

The lifting speed of the valve stem 11 on which the permanent magnet 15 is installed and the lifting speed of the oil pumping member 50 are proportional. Accordingly, as the rotational speed (rpm) of the internal combustion engine in a proportional relationship with the lifting speed of the valve stem 11 increases, the oil is discharged from the injector 40 and the gap 28 between the valve stem 11 and the valve guide 25 increases. ), the amount of lubricating oil inflow increases. As a result, according to the lifting speed of the valve stem 11, an appropriate amount of lubricating oil flows into the gap 28 between the valve stem 11 and the valve guide 25, and thus damage or malfunction of the valve stem 11 (異常) is prevented, the durability of the valve stem 11 is improved, and the emission of air pollutants contained in the exhaust gas is also reduced.

Although not clearly shown in the drawings, the upper space 49 and the lower space 48 may be filled with an oil absorber made of a foamed resin that elastically contracts to enable volume restoration, such as, for example, a sponge. The oil absorber absorbs lubricating oil flowing into the upper space 49 and the lower space 48. If the upper space 49 and the lower space 48 are not filled with an oil absorber, the lubricating oil flows down by gravity when the valve stem 11 does not move up and down because the internal combustion engine does not operate. It may flow out to the outside of the oil injector 40 through 45 and flow down along the gap 28 between the valve stem 11 and the valve guide 25 to flow into the combustion chamber of the internal combustion engine. However, if the oil absorber is filled in the upper space 49 and the lower space 48, when the internal combustion engine is not operated, lubricating oil is held and held by the oil absorber, so that it is lubricated through the oil outlet hole 45. Oil does not leak out of the oil injector 40.

In addition, although not clearly shown in the drawings, a check valve may be installed in the fluid through hole 51. In this case, when the oil pumping member 50 rises and the pressure in the upper space 49 becomes higher than the pressure in the lower space 48, the check valve opens the fluid through hole 51 and the lubricating oil is transferred to the upper space. It moves from the space 49 to the lower space 48, but when the oil pumping member 50 descends and the pressure in the upper space 49 becomes less than the pressure in the lower space 48, the check valve causes the fluid through-hole. Closing 51 prevents the lubricating oil from flowing back from the lower space 48 to the upper space 49.

The sealing lip 60 is made of rubber, is bonded to the upper side of the injector housing 41 so as not to cover the oil inlet hole, and elastically adheres to the outer circumferential surface of the valve stem 11. It extends toward. The inner end of the sealing lip 60 forms a circular orbit centered on the axis CL and is in elastic contact with the outer circumferential surface of the valve stem 11 without any gap, so that the outer circumferential surface of the valve stem 11 and the inner circumferential surface of the injector housing 41 Limit the lubricating oil flowing into the gap.

The rubber member 55 is made of rubber and is bonded and supported on the inner circumferential surface of the rigid frame 31. The rubber member 55 includes an oil injector joint 57 bonded to the injector housing 41 so that the outer circumferential surface of the injector housing 41 is supported by the rigid frame 31, and the upper end 27 of the valve guide 25. It is interposed between the upper end of the upper end 27 of the valve guide 25 and the lower side of the injector housing 41 without covering the valve guide contact portion 56 and the oil outlet hole 45 in close contact with the outer circumferential surface. A spacer portion 58 is provided to separate the injector housing 41 and the valve guide 25. The rubber member 55 is sealed without penetration of lubricating oil and foreign substances between the inner circumferential surface of the rigid frame 31 and the injector housing 41, between the rigid frame 31 and the upper end of the valve guide 27, and external force is applied to the rigid frame. Even if applied to (31), the oil injector 40 and the valve guide upper end 27 perform a function of buffering so that it is relieved and transmitted.

On the other hand, although not clearly shown in the drawings, an adhesive for strengthening the bonding force with the rubber member 55 may be applied to the inner circumferential surface of the rigid frame 31 and the outer circumferential surface of the injector housing 41 to be bonded to the rubber member 55. On the other hand, in the drawing, the injector housing 41 is bonded and supported to the rigid frame 31 via the rubber member 55, and the rigid frame 31 is attached to the upper end 27 of the valve guide 25 and the rubber member 55 ), but the injector housing 41 is directly press-fitted and supported by the rigid frame 31 without the rubber member 55, and the rigid frame 31 is the valve guide 25 It may be directly press-fit and fixed to the upper end portion 27 of the.

The present invention has been described with reference to the embodiments shown in the drawings, but these are merely exemplary, and those of ordinary skill in the art will appreciate that various modifications and other equivalent embodiments are possible therefrom. Therefore, the true scope of protection of the present invention should be determined only by the appended claims.

10: internal combustion engine valve 11: valve stem
20: cylinder head 24: valve spring
25: valve guide 30: valve stem seal
31: rigid frame 40: oil injector
41: injector housing 50: oil pumping member
60: sealing lip 55: rubber member

Claims (9)

Controlling the inflow amount of lubricating oil flowing between the valve stem with a permanent magnet installed therein and the valve guide that is fixed to the cylinder head and guides the elevation of the valve stem,
A rigid frame surrounding an upper end of the valve guide and fixedly supported by the valve guide; And, an oil injector disposed above the valve guide inside the rigid frame and supported by the rigid frame,
The oil injector, an injector housing having an oil inlet hole formed on an upper side and an oil outlet hole formed on a lower side thereof, and installed to be elevating in the inner space of the injector housing, and attracted by the magnetic force of the permanent magnet It comprises an oil pumping member (oil pumping member) to move up and down in synchronization with the lifting of the valve stem,
The inner space of the injector housing is divided into an upper space above the oil pumping member and a lower space below the oil pumping member,
When the valve stem rises and the oil pumping member rises, the upper space becomes narrower, and the lower space becomes wider as the upper space becomes narrower, and the lubricating oil moves from the upper space to the lower space,
When the valve stem is lowered and the oil pumping member is lowered, the lower space is narrowed and pressurized so that the lubricating oil in the lower space is discharged between the valve stem and the valve guide through the oil outlet hole, and the lower space is narrowed. A valve stem seal, characterized in that the lubricating oil flows into the upper space through the oil inlet hole while the upper space is widened. The method of claim 1,
The oil injector further includes a check valve that opens the oil inlet hole when the oil pumping member descends and closes the oil inlet hole when the oil pumping member rises. . The method of claim 1,
A valve stem seal, characterized in that a fluid through hole is formed in the oil pumping member to allow lubricating oil to move between the upper space and the lower space. The method of claim 1,
The valve stem seal, characterized in that the upper space and the lower space are filled with an oil absorber that absorbs lubricating oil, which is made of a foamed resin that is elastically contracted to restore volume. The method of claim 1,
A valve stem seal comprising a rubber (rubber), a sealing lip that is bonded and supported to the injector housing so as not to cover the oil inlet hole and extends elastically to the outer circumferential surface of the valve stem; . The method of claim 1,
A rubber member made of rubber and bonded and supported on the inner circumferential surface of the rigid frame; further comprising,
The rubber member includes an oil injector joint portion bonded to the injector housing so that the injector housing is supported by the rigid frame, and a valve guide contact portion in close contact with an outer circumferential surface of an upper end portion of the valve guide. The method of claim 6,
The rubber member further comprises a spacer portion interposed between the injector housing and the valve guide and spaced apart from the injector housing and the valve guide without blocking the oil outlet hole. A valve stem having a permanent magnet installed therein to open and close a port formed in the cylinder head of the internal combustion engine; A valve guide fixed to the cylinder head to guide the elevation of the valve stem; And, the valve stem seal of any one of claims 1 to 7, an internal combustion engine valve comprising a. The method of claim 8,
When the valve stem is raised and lowered, the permanent magnet is raised or lowered between the height of the upper end and the lower end of the injector housing.

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