JPH0874544A - Valve system of engine - Google Patents

Abstract

PURPOSE: To restrain partial abrasion on the tip of a valve stem, so as to improve the life of the valve stem by enabling the relative movement between a first moving member to be brought in contact with a cam and a second moving member to be brought in contact with the stem tip to be regulated. CONSTITUTION: Oil pressure in an oil pan 38 is supplied into an oil pressure chamber 37 by an oil pressure pump 39 through oil pressure passage 41, a groove 42, and a passage 43. As a result, a plate 34 is moved toward the first position from the second position against an energizing force of a spring 45, and the plate is partially formed on a slider 32 and advanced into an annular groove 321. And the plate 34 stops in the first position by the small diameter part of the slider main body part 322. Thereby, the relative movement between the slider 32 and the plate 34, namely, between an outer body 21 and inner bodies 24, 25, is prevented. Since the contact of the tip of a stem 14 with the plate 34 is avoided, partial abrasion on the tip of the stem 14 can be restrained, and the life of the stem 14 is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve operating system for an engine having a valve stopping mechanism for constantly stopping intake and exhaust valves.

[0002]

2. Description of the Related Art Heretofore, as a valve operating system of this type of engine, one disclosed in Japanese Patent Laid-Open No. 6-10637 has been known. This is an intake / exhaust valve that opens and closes an intake hole or an exhaust hole that opens in the engine combustion chamber, a valve stem connected to the intake / exhaust valve, a cam supported by a cam shaft, and a gap between the cam and the valve stem. And a valve stop mechanism capable of maintaining the intake and exhaust valves in the closed state. Here, the valve stopping mechanism includes a body slidably disposed in the cylinder head in the axial direction of the intake / exhaust valve, a body hole formed in the body, and having a shaft center orthogonal to the shaft center of the stem, A first stem insertion / extraction hole extending in the axial direction of the stem, wherein the hydraulic pressure acting on one end slides in the body hole so that the stem tip can enter the stem insertion / extraction hole.
A plunger that is biased to a position, and a spring that biases the plunger against the hydraulic pressure and maintains the plunger at a second position where the stem tip cannot enter the stem entry / exit hole when the hydraulic pressure is not acting. A slider made of wear-resistant material attached to the plunger so as to come into contact with the tip of the valve stem when the intake / exhaust valve operates, and a valve spring that biases the valve stem in the direction of closing the intake / exhaust valve. ing.

In the above-mentioned device, the slider made of the wear resistant material avoids the contact between the plunger and the tip of the valve stem to prevent the uneven wear of the plunger and the deviation of its axial center.

[0004]

However, in the above-mentioned device, although the contact between the plunger and the tip of the valve stem can be avoided, the slider that moves together with the plunger in the direction orthogonal to the axis of the valve stem and the tip of the valve stem. Because of the contact with the valve stem, a load from the slider in the direction orthogonal to the axis of the valve stem acts on the stem tip, causing the valve stem tip to wear unevenly, resulting in
If used for a long time, the tip of the valve stem may be scraped. Therefore, as the valve stem is used for a long period of time, the lift amount of the intake / exhaust valve is gradually reduced, which causes a problem that an appropriate lift amount cannot be secured. That is, there is a problem that the life of the valve stem is shortened.

Therefore, the present invention aims to improve the life of the valve stem by suppressing the uneven wear of the tip portion of the valve stem.
This is a technical issue.

[0006]

The technical means (hereinafter referred to as technical means) taken in the invention of claim 1 in order to solve the above-mentioned technical problem is an intake hole or exhaust opening in a combustion chamber of an engine. An intake / exhaust valve that opens and closes a hole to connect to the stem, and a first biasing the stem in a direction to close the intake / exhaust valve
It has a spring, a cam supported around the cam shaft, and a valve stop mechanism arranged between the cam and the stem, and the valve stop mechanism is provided in a hole formed in the cylinder head of the engine. A first movable member that is arranged movably in the axial direction of the intake / exhaust valve and is in contact with the cam, and a first movable member that is slidable in the axial direction of the intake / exhaust valve and is movable relative to the first movable member. A second movable member that is provided and abuts on the tip of the stem;
It is constituted by relative movement restricting means capable of restricting relative movement between the movable member and the second movable member.

In the above technical means, the first movable member is a body having a slider guide hole extending in the axial direction of the stem, and the second movable member is slidably arranged in the slider guide hole. In the case of using the slider, the relative movement restricting means is defined as the axial center of the stem formed in the body in order to reliably restrict the relative movement between the first movable member and the second movable member. A body hole having orthogonal shaft centers, a guide groove formed in the slider so as to overlap with the body hole, and slidably disposed in the body hole and entering the guide groove by hydraulic pressure acting on one end. The third movable member that is urged to any one of the second position and the second position that is removed from the guide groove, and the third movable member that is urged in a direction that opposes the hydraulic pressure and that is at one end of the third movable member. No. 3 when hydraulic pressure is not working Preferably consist a second spring to maintain the member to the other position of the first and second position.

In order to shorten the axial length of the valve stop mechanism,
It is preferable that the third movable member is a plate-shaped member.

In order to ensure that the plate-shaped member can enter the movable member guide groove even when the body and the slider rotate relative to each other, the slider has a columnar shape, and the guide groove has the thickness of the plate-shaped member. It is preferable to use an annular groove having an opening width substantially the same as

Further, when the plate-shaped member moves from the first position to the second position, interference between the plate-shaped member and the guide groove is avoided, and
In order to prevent the slider from falling downward when the plate-shaped member is in the second position, the slider has a first flange extending in the axial direction of the body hole so that its lower surface is along the upper surface of the guide groove. It is preferable that the first flange portion is placed on the plate-shaped member when the plate-shaped member exists in the second position.

Further, in order to prevent the stem from interfering with the body or the third movable member, it is preferable to provide the slider with a guide portion for guiding the outer peripheral surface of the stem.

In order to make the slider slide more smoothly, it is preferable that the slider is provided with a second flange portion projecting upward from the upper surface of the slider guide hole so as to always contact the outer peripheral surface of the slider guide hole.

Further, in order to always contact the body with the cam, it is preferable to newly install a fourth spring for urging the body toward the cam. Here, when the body moves to the cam side by the fourth spring when the third movable member is in the second position, the slider is biased toward the stem in order to prevent the slider from floating up following it. It is preferable to newly install a third spring whose urging force is smaller than that of the first spring.

In order to shorten the axial length of the valve stop mechanism,
For the third spring, it is preferable to employ a tapered spring whose diameter is reduced toward the tip.

In order to shorten the axial length of the valve stop mechanism,
It is preferable to use a torsion bar spring as the third spring.

Further, in order to shorten the axial length of the valve stopping mechanism, it is preferable to employ a torsion bar spring as the second spring.

[0017]

The operation of the above technical means will be described.

When the relative movement restricting means restricts the relative movement of the first movable member and the second movable member, the first movable member causes the second movable member to move when the cam engages with the first movable member. And the stem move against the urging force of the first spring, and as a result, the intake and exhaust valves open and close.

On the other hand, when the relative movement restricting means releases the restriction of relative movement between the first movable member and the second movable member, the cam engages with the first movable member and the first movable member sucks. Even if the exhaust valve moves in the opening direction, the force acting on the first movable member is not transmitted to the second movable member and the stem. Move in the direction to close the valve.
As a result, the intake / exhaust valve always remains inactive.

According to the above technical means, since the second movable member that moves in the axial direction of the intake / exhaust valve is brought into contact with the stem tip portion, the stem tip portion is moved in the direction orthogonal to the axial center of the stem. No load is applied, and as a result, uneven wear of the stem tip is suppressed and the stem tip is not scraped. Therefore, the life of the valve stem is improved.

When the first movable member is a body having a slider guide hole extending in the axial direction of the stem, and the second movable member is a slider slidably disposed in the slider guide hole. In the above, the operation of the relative movement restricting means when the relative movement restricting means is constituted by the body hole, the guide groove, the movable member and the second spring as described above will be described.

The third pressure is generated by the hydraulic pressure or the action of the second spring.
When the movable member exists at the first position where the movable member has entered the guide groove formed in the slider, the slider and the third movable member engage with each other, so that the pressing force of the cam is applied to the slider from the body through the third movable member. Transmitted. That is, at this time, relative movement between the body and the slider is restricted.

On the other hand, when the third movable member is in the second position where it is disengaged from the guide groove due to the action of hydraulic pressure or the second spring, the engagement between the slider and the third movable member is released, so that the pressing force of the cam is released. Is transmitted from the body to the third movable member, but is not transmitted from the third movable member to the slider. That is, at this time, the body and the slider move relative to each other.

In the case where the relative movement restricting means is constructed as described above, the slider is so arranged as to come into contact with the stem between the stem and the third movable member which move in the directions orthogonal to each other. Stem tip and third
The movable members do not come into contact with each other, and as a result, uneven wear of the stem tip portion is suppressed and the life of the stem is improved.

If the slider and the third movable member are made of a wear resistant material, it is possible to reduce the abrasion of the third movable member and the guide groove when the third movable member enters the guide groove. As a result, the lift amount of the intake / exhaust valve can be maintained at an appropriate value (constant) even if the stem is used for a long period of time.

Here, if the third movable member is a plate-shaped member, the thickness of the third movable member becomes thin, so that the axial length of the valve stopping mechanism can be shortened accordingly.

If the slider is cylindrical, the body and the slider can rotate relative to each other. In that case,
If the guide groove is an annular groove, the plate member can surely enter the guide groove even if the body and the slider rotate relative to each other. Further, when the opening width of the guide groove is made substantially equal to the thickness of the plate member, it is possible to prevent the plate member from rattling when the plate member enters the guide groove.

Further, the slider is provided with a flange portion whose lower surface extends in the axial direction of the body hole so that the lower surface thereof follows the upper surface of the guide groove, and the flange portion is formed when the plate-shaped member is in the second position. When the plate-shaped member is mounted on the upper side, it is possible to avoid interference between the plate-shaped member and the movable member guide groove when the plate-shaped member moves from the second position to the first position, and it is possible to smoothly slide the plate-shaped member. Become. Further, it is possible to prevent the slider from falling to the outside when the plate member is in the second position, and
When the slider is in the position, the slider is reliably positioned with respect to the plate member.

Further, when the slider is provided with the guide portion for guiding the outer peripheral surface of the stem, the stem is prevented from interfering with the body and the third movable member, the switching property of the relative movement regulation is improved, and the stem is improved. The uneven wear of the body and the third movable member is suppressed.

In addition, the second protrusion protruding upward from the upper surface of the slider so as to always contact the outer peripheral surface of the slider guide hole.
By providing the flange portion, it is possible to suppress backlash when the slider slides.

Further, if a fourth spring for urging the body toward the cam is newly provided, the body can be always brought into contact with the cam even when the third movable member is in the second position. Here, if a third spring is newly installed in which the slider is urged toward the stem and the urging force thereof is smaller than the urging force of the first spring, the fourth spring when the third movable member is in the second position is provided. When the body moves to the cam side due to the spring, the slider can be prevented from floating up following the cam. As a result, when the third movable member is present at the second position, the slider is reliably positioned, so that the third movable member is moved to the second position.
It is possible to smoothly move from the position to the first position.

If a taper spring whose diameter is reduced toward the tip of the third spring is adopted, the height of the spring itself can be made lower than that of the cylindrical spring. The axial length of the valve stop mechanism can be shortened.

Further, if a torsion bar spring is adopted as the third spring, the compression space can be reduced as compared with the compression space of the coil spring, so that the axial length of the valve stopping mechanism can be shortened accordingly.

Further, when a torsion bar spring is adopted as the second spring, the space occupied by the coil spring in the stem axial direction can be reduced as compared with the space occupied by the coil spring, and the axial length of the valve stop mechanism is shortened accordingly. be able to.

[0035]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings.

The engine valve operating system according to the first embodiment will be described with reference to FIGS. Here, FIGS. 1 and 2 show an engine valve operating device when the intake and exhaust valves are in operation (opening and closing), and FIGS. 3 to 5 are engine operation devices when the intake and exhaust valves are at rest (at stop). 2 shows a valve device.

The engine valve operating system 10 shown in FIG. 1 is attached to and detached from a cam 12 supported by a cam shaft 11 and a seat surface 16 formed on a cylinder head 15 of the engine. ) An intake / exhaust valve 13 that opens and closes an intake hole or an exhaust hole (not shown) that is opened inside, and a valve stem (stem) 14 connected to the intake / exhaust valve 13.
And a valve spring (first spring) 17 that has one end engaged with a retainer 19 fixed on the outer circumference of the valve stem 14 via a cotter 18 and biases the valve stem 14 in a direction of closing the intake / exhaust valve 13. And a valve stop mechanism 20, which is the subject matter of the present invention, disposed between the cam 12 and the valve stem 14. The valve stem 14 is made of a heat resistant material (for example, heat resistant steel).

In the valve stop mechanism 20, an outer body 21 having a bottomed cylindrical shape is slidable in a cylinder hole 15a formed in the cylinder head 15 of the engine so as to extend in the axial direction of the intake / exhaust valve 13. A disc-shaped outer shim 22 having an engagement surface with the cam 12 is arranged on the upper surface of the outer body 21. This outer shim 22
The clearance between the base circle of the cam 12 and the valve stop mechanism 20 is adjusted, and the outer diameter of the outer shim 22 is slightly smaller than the diameter of the cylinder hole 15a.

In the inner space 23 of the outer body 21,
Two vertically divided inner bodies 24 and 25 are disposed so as to be movable integrally with the outer body 21. A spring (fourth spring) 26 is provided between the lower inner body 25 and the bottom surface of the cylinder hole 15a, and the inner body 24, 25 is pressed against the outer body 21 (that is, the intake / exhaust valve 13 is closed). ). A spring seat 27 is arranged between the spring 26 and the lower inner body 25. The upper inner body 24 is non-rotatably supported with respect to the outer body 21 via a detent pin 28. The lower inner body 25 is formed with a first slider guide hole 29 having an axis coinciding with the axis of the valve stem 14, and the upper inner body 24 has an axis coincident with the axis of the valve stem 14. A second slider guide hole 30 having a diameter larger than that of the first slider guide hole 29 is formed. A body hole 31 having an axis perpendicular to the axis of the valve stem 14 is formed between the inner bodies 24 and 25, and the first and second slider guide holes 29 and 3 are formed.
It intersects between 0. The outer body 21 and the inner bodies 24, 25 described above constitute the body of the present invention. Further, both the inner bodies 24 and 25 described above may be integrally formed, or the outer body 21 and both inner bodies 24 and 25 may be integrally formed.

A slider 32 is movably guided in the first and second slider guide holes 29 and 30 so as to be constantly in contact with the valve stem 14, and the slider 32 is
A spring (third spring) 33 arranged between the outer body 21 and the bottom surface of the outer body 21 biases the intake / exhaust valve 13 in the opening direction. The biasing force of the spring 33 is set to be smaller than the biasing force of the valve spring 17.

The slider 32 comprises an annular groove (movable member guide groove) 321, a main body 322 having an H-shaped cross section, a flange 323, and a stem guide 324.

The annular groove 321 is opened in the radial direction of the slider 32, can overlap the body hole 31, and can be overlapped with the body hole 31.
The opening width is almost the same as the axial width of the. The main body 322 is
The diameter of the first slider guide hole 29 is substantially the same as that of the first slider guide hole 29, and the lower surface of the first slider guide hole 29 contacts the tip of the valve stem 14. The lower surface of the flange portion 323 has an annular groove 32.
The slider 32 projects in the radial direction of the slider 32 along the upper surface of the slider 1, and the outer diameter thereof is substantially the same as the diameter of the second slider guide hole 30. The upper surface of the flange portion 323 serves as a seat for the spring 33 described above. The stem guide portion 324 is an annular wall extending downward from the lower surface of the main body portion 322, the inner diameter thereof is slightly larger than the diameter of the valve stem 14, and the outer diameter thereof is the first slider guide hole. The diameter is substantially the same as 29. Therefore, the valve stem 14 can slide smoothly and the stem guide portion 324
Can also slide smoothly in the axial direction. The slider is made of a wear resistant material (for example, carburized material).

The slider 3 is provided in the body hole 31 described above.
A plate 34 having a thickness substantially the same as the opening width of the second annular groove 321 or the axial width of the intake / exhaust valve of the body hole 31 is slidably guided. The intake / exhaust valve 1 is attached to the plate 34.
A through hole 35 penetrating in the axial direction of 3 is formed, and the diameter of this through hole 35 is substantially the same as the outer diameter of the large diameter portion of the slider body 322 and the stem guide portion 324. A semicircular cutout 36 is formed on the left end surface of the plate 34. The plate 34 is detached from the annular groove 321 from the first position (the state shown in FIGS. 1 and 2) in which the plate 34 enters the annular groove 321 formed in the slider 32 (that is, straddles the body hole 31 and the annular groove 321). It moves to the second position (state of FIGS. 3 and 4). Here, when the plate 34 is in the first position, as shown in FIG.
As shown in FIG. 5, the axial center of the through hole 35 is displaced from the axial center of the slider 32, so that the slider 32 cannot move relative to the inner bodies 24 and 25 together with the valve stem 14. On the other hand, when the plate 34 is in the second position, the axis of the through hole 35 is aligned with the axis of the slider 32 as shown in FIG. 4, so that the slider 32 together with the valve stem 14 as shown in FIG. , 25 can be moved relative to each other. Further, as shown in FIG. 5, since the diameter of the flange portion 323 of the slider 32 is larger than the diameter of the through hole 35 of the plate 34, when the plate 34 is in the second position, the flange portion 323 is placed on the plate 34. It has been placed on the
This allows the plate 34 to move smoothly from the second position to the first position without interfering with the slider 32, and the slider 32 is positioned with respect to the plate 34. The plate 34 is made of a wear resistant material (for example, carburized material).

A hydraulic chamber 37 is formed between the left end of the plate 34 and the outer body 21, and the hydraulic pressure in an oil pan 38 is controlled by a hydraulic pump 39, an electromagnetic switching valve 40, a hydraulic passage 41 formed in a cylinder head, and an outer body 21. It is supplied through an annular groove 42 and a passage 43 formed in the. The electromagnetic switching valve 40 is electrically connected to a controller (not shown) into which the operating state of the engine such as the engine speed and the engine load is input, and the controller switches the state of FIG. It can be switched to the 2 state. The plate 34 can be moved from the second position shown in FIGS. 3 and 4 to the first position shown in FIGS. 1 and 2 by the hydraulic pressure acting on the hydraulic chamber 37. still,
The hydraulic pressure in the hydraulic chamber 37 is changed to the passage 43, the groove 42, the hydraulic passage 41.
Also, the oil can be discharged to the oil pan 38 via the electromagnetic switching valve 40.

On the other hand, a spring chamber 44 is formed between the left end of the plate 34 and the outer body 21, and the spring chamber 44 has a width in the axial direction larger than the axial width of the body hole 31. It is formed by processing 25. A spring (second spring) 45 is arranged in the spring chamber 44, and the plate 3
4 is urged in a direction that opposes the hydraulic pressure, that is, in a direction that reduces the volume of the hydraulic chamber 37. Here, the urging force of the spring 45 is set to be smaller than the force due to the hydraulic pressure, and when the hydraulic pressure is not acting in the hydraulic chamber 37, the urging force of the spring 45 causes the plate 34 to move toward the plate 34.
The second position shown in FIG. In addition, the lower inner body 2
5 has an oil drain hole 4 that opens in the spring chamber 44.
6 is formed so that a small amount of oil that enters the spring chamber 44 from the hydraulic chamber 37 can be discharged to the outside of the valve stop mechanism 20.

The plate 34 may be biased from the first position to the second position by hydraulic pressure and the plate 34 may be biased to the second position by the spring 45.

The operation of the valve operating system 10 of the engine according to the first embodiment constructed as described above will be described.

When the engine is started, the camshaft 11
Starts to rotate, and as a result, the cam 12 is rotationally driven.
First, when it is desired to constantly open and close the intake / exhaust valve 13, the controller switches the electromagnetic switching valve 40 to the state shown in FIG. Then, the hydraulic pressure in the oil pan 38 is supplied to the hydraulic chamber 37 via the hydraulic passage 41, the groove 42, and the passage 43 by the hydraulic pump 39. As a result, the plate 34 moves from the second position to the first position against the biasing force of the spring 45, and a part of the plate 34 enters the annular groove 321 formed in the slider 32 (that is, the plate 34). Straddles the body hole 31 and the annular groove 321), and as a result, the plate 34 stops at the first position as shown in FIG. 1 due to the small diameter portion of the slider body 322. This prevents relative movement between the slider 32 and the plate 34, that is, the outer body 21 and the inner bodies 24, 25.

Therefore, when the rotation of the cam 12 advances from the state where the cam 12 is in contact with the outer shim 22 at the base circle and starts to contact the outer shim 22 on the cam surface, the outer body 21 and the inner bodies 24, 25 together with the slider 32, the valve spring 17 and the spring 26. It begins to sink downward in the figure against the urging force of. That is, while the outer shim 22 is engaged with the cam surface of the cam 12, the force is transmitted to the outer body 21 → inner body 24 → plate 34 → slider 32 → valve stem 14 → intake / exhaust valve 13, and the cam surface cam According to the profile, the intake / exhaust valve 13 moves downward in the drawing against the urging force of the valve spring 17, and the intake / exhaust valve is separated from the seat surface 16 to perform intake or exhaust. At this time, the outer body 21 may rotate with respect to the cylinder hole 15a, but in that case, since the outer shim 22 has a disk shape, the cam 12 is always engaged with the outer shim 22. The area of the engaging region of is always constant.

On the other hand, when it is desired to suspend the operation of the intake / exhaust valve 13, the electromagnetic switching valve 40 is switched to the state shown in FIG. 3 by the controller. Then, the hydraulic pressure in the hydraulic chamber 37 passes through the passage 43, the groove 42, and the hydraulic passage 41, and the oil pan 38
Is discharged to. As a result, the urging force of the spring 45 moves the plate 34 from the first position toward the second position, a part of the plate 34 comes out of the annular groove 321, and the plate 34 is inserted into the through hole 35 as shown in FIG. It stops at the second position where the axis coincides with the axis of the valve stem 14, that is, the slider 32. As a result, the slider 32 and the plate 34, that is, the outer body 21 and the inner body 2
Relative movement between 4, 25 is possible.

Therefore, even if the rotation of the cam 12 advances from the state where the cam 12 is in contact with the outer shim 22 at the base circle and the cam surface begins to make contact with the outer shim 22, the force of the cam 12 is transmitted to the outer body 21 and the inner bodies 24, 25. ,
It is not transmitted to the slider 32 and the valve stem 14. As a result, the slider 32 is pushed by the valve stem 15 by the urging force of the valve spring 17, the main body portion 322 and the stem guide portion 324 are in the first slider guide hole 29 and the through hole 35, and the flange portion 323 is in the second slider guide hole. While being respectively guided by 30, they move upward in the figure against the biasing force of the spring 33. In this way, the cam 12
Since the force due to is not transmitted to the intake / exhaust valve 13, the intake / exhaust valve 13 is maintained in the closed state, that is, the state of being seated on the seat surface 16, and intake or exhaust is not performed. At this time as well, the first body 30 may rotate, but in that case, since the outer shim 22 is in the shape of a disk, the cam 12 has the outer shim 22.
The engagement area of the cam surface at that time is always constant.

As described above, in the first embodiment, between the valve stem 14 and the plate 34 which move in the directions orthogonal to each other, the valve stem 14 is brought into contact with the valve stem 14 and the stem 14 is moved.
Since a slider having an axial center coinciding with the axial center of is intervened, contact between the tip of the stem 14 and the plate 34 is avoided, so that uneven wear of the tip of the stem 14 can be suppressed and it can be used for a long period of time. However, the tip of the stem 14 is not scraped. Therefore, the life of the stem 14 is improved.

Further, since the slider 32 and the plate 34 are made of a wear resistant material, the annular groove 3 of the plate 34 is
It is possible to suppress uneven wear of the annular groove 321 and the plate 34 at the time of entering the vehicle 21. As a result, the annular groove 321 and the plate 34 are prevented from being scraped even after long-term use. Therefore, the lift amount of the intake / exhaust valve 13 can be maintained at an appropriate value (constant) even after long-term use.

Further, part of the plate 34 is the slider 32.
Since the plate 34 is in the second position shown in FIG. 3, the biasing force of the valve spring 17 acting on the valve stem 14 pushes up only the stem 14 and the slider 32 when the plate 34 is in the second position shown in FIG. Since it is sufficient to apply only the force, the set load of the valve spring 17 can be made small.

Further, since the plate 34 is adopted, the thickness of the plate 34 is reduced, so that the axial length of the valve stopping mechanism 20 can be shortened accordingly.

Further, since the groove 321 for advancing the plate 34 formed in the slider 32 is annular, even if the outer body 21, the inner bodies 24, 25 and the slider 32 rotate relative to each other, the plate 34 is surely annular groove 321. Will be able to enter. Further, since the opening width of the annular groove 321 is made substantially the same as the thickness of the plate 34, the plate 34
It is possible to prevent the plate 34 from rattling when entering the annular groove 321.

The lower surface of the slider 32 has an annular groove 3
A flange portion 323 extending in the radial direction of the slider 32 is provided along the upper surface of the slider 21, and as shown in FIG. 5, when the plate 34 is in the second position shown in FIG. I decided to place it on
The plate 34 moves from the second position shown in FIG. 3 to the first position shown in FIG.
When moving to the position, interference between the plate 34 and the annular groove 321 can be avoided, and the plate 34 can smoothly slide. Further, the slider 32 can be prevented from falling outside when the plate 34 is in the second position, and the slider 32 is reliably positioned with respect to the plate 34 when the plate 34 is in the second position.

Further, since the slider 32 is provided with the stem guide portion 324 for guiding the outer peripheral surface of the stem 14, it is possible to avoid the outer peripheral surface of the distal end portion of the stem 14 from interfering with the lower inner body 25 and the plate 34, and to move relatively. It is possible to improve the switching property of the regulation and suppress uneven wear of the outer peripheral surface of the tip portion of the stem 14, the lower inner body 25, and the plate 34.

Further, since the outer shim 22 having the cam engaging surface is disk-shaped, even if the outer body 21 rotates, the cam 1
Since 2 always engages only with the outer shim 22, the above-described operation can be reliably performed even if the outer body 21 rotates. That is, since the rotation prevention mechanism is unnecessary, uneven wear is reduced accordingly.

The outer diameter of the outer shim 22 is set to the cylinder hole 1
Since the diameter is set to be slightly smaller than the diameter of 5a, the engagement area with the cam 12 is sufficiently secured, and as a result, the cam 1
A lift amount of 2 is secured.

Further, since the detent 28 is provided between the outer body 21 and the upper inner body 24, the relative rotation between the outer body 21 and the upper inner body 24 is restricted, and as a result, the hydraulic chamber formed in the body hole 31 is restricted. 37
It is possible to prevent the communication between the groove 42 formed in the outer body 21 and the passage 43 from being interrupted.

Next, a valve operating system for an engine according to the second embodiment will be described with reference to FIGS. Here, FIGS. 6 and 7 show the engine valve operating device when the intake and exhaust valves are operating (when opening and closing), and FIGS. 8 and 9 are the engine operating devices when the intake and exhaust valves are at rest (at stop). 2 shows a valve device.

The engine valve operating system 10 according to the second embodiment.
Is basically similar to that of the first embodiment,
Only the points different from the first embodiment will be described. 6 to 9
In the above, the same reference numerals are given to those having substantially the same structure as the first embodiment.

In FIG. 6, the slider guide hole 2 is formed in the outer body 21, the outer shim 22, the upper inner body 24, and the lower inner body 25 so as to penetrate them.
90 is formed, and this slider guide hole 290 corresponds to the first slider guide hole 29 of the first embodiment. A bottomed cylindrical retainer 47 is provided so as to close the upper opening of the slider guide hole 290, and the retainer 47 holds the flange portion 471 between the outer body 21 and the upper inner body 24 to thereby guide the slider. Hole 290
It is supported so as not to come out of the upper opening of the.

The slider 32 is movably guided in the slider guide hole 290, and the diameter of the large diameter portion of the slider body 322 having an H-shaped cross section is substantially the same as the diameter of the slider guide hole 290. The slider 32 is biased in a direction to open the intake / exhaust valve by a spring 33 arranged between the slider 32 and the bottom surface of the retainer 47. The slider 32 has a flange portion 323 as in the first embodiment.
And does not have the stem guide portion 324.

A plate 34 is slidably arranged in the body hole 31, but the shape of the plate 340 is slightly different from the shape of the plate 34 of the first embodiment. That is, the plate 34 has a U-shaped cutout 341 having an R portion. The plate 34 has an R-shaped groove 32 shown in FIGS.
When it is in the first position for entering 1, the slider 32 and the plate 34 engage with each other as shown in FIG.
Slider 32, outer body 21 and inner body 2
Relative movement between 4 and 25 is restricted. On the other hand, when the plate 34 is in the second position where the R portion shown in FIGS. 8 and 9 is disengaged from the annular groove 321, the slider 32 and the plate 34 do not engage with each other as shown in FIG. 21 and Inner Body 24, 25
A relative movement between and becomes possible.

The operation of the engine valve operating system 10 according to the second embodiment is substantially the same as that of the first embodiment.
The description is omitted.

In the second embodiment, each body 21, 24, 2 is
5 and the outer shim 22 are formed so as to pass through the slider guide hole 290, the upper opening thereof is closed by the bottom surface of the retainer 47, and one end of the slider biasing spring 33 is engaged with the retainer 47. Compared with the case where the spring 33 is engaged with the outer body 21 as in the first embodiment, the axial length of the valve stop mechanism 20 can be shortened.

FIG. 10 is a sectional view of a valve operating system 10 for an engine according to the third embodiment. As is clear from the figure,
The third embodiment is different from the first embodiment only in that the slider 32 is provided with a flange portion (second flange portion) 325 that protrudes upward from the flange portion 323 so as to always contact the slider guide hole 30. Is.

In the third embodiment, the flange portion 325 on the upper portion of the slider 32 is always in contact with the slider guide hole 30 and the lower guide portion 324 is always in contact with the slider guide hole 29. Sometimes, the slider 32 can be prevented from rattling. Therefore, plate 3
The switchability between the first and second positions of No. 4 is improved.

FIG. 11 is a sectional view of a valve operating system 10 for an engine according to the fourth embodiment. As is clear from the figure,
The fourth embodiment is different from the first embodiment only in that the body 210 in which the outer body 21 and the upper inner body 24 of the first embodiment are integrated is used and that the ring-shaped plate 48 is arranged between the body 210 and the plate 34. It is different from the example.

In the fourth embodiment, since the outer body 21 and the upper inner body 24 are integrated, the rotation prevention pin 2
Since 8 etc. can be eliminated, it is cost effective.

Further, since the ring-shaped plate 48 is arranged between the body 210 and the plate 34, the contact area with the plate 34 can be increased, so that the plate 34 can be moved more smoothly.

FIG. 12 is a sectional view of the valve operating system 10 for an engine according to the fifth embodiment. As is clear from the figure,
In the fifth embodiment, the spring 33 that biases the slider 32 toward the stem 14 adopts a tapered spring whose diameter decreases toward the tip, and the location of the tapered spring 33 is the same as in the first embodiment. It is different from the example.

Explaining this point in detail, the slider 3
An annular spring seat 326 is integrally formed on the lower portion of the second stem guide portion 324.
The tip of the tapered spring 33 described above is supported. Further, the end of the tapered spring 33 is supported by the lower inner body 25.

In the fifth embodiment, since the spring 33 has a taper spring whose diameter becomes smaller toward the tip, the height of the spring itself can be made lower than that of the cylindrical spring. The axial length of the valve stop mechanism 20 can be shortened.

Further, the spring seat 326 in which the tip of the tapered spring 33 is provided below the stem guide portion 324.
Since the end is supported by the lower inner body 25, there is no need to provide a space for arranging the spring between the upper surface of the slider 32 and the outer body 21, so that the axial length of the upper inner body 24 is reduced by that much. Can be shortened. Further, the axial length of the lower inner body 25 does not increase. Therefore, the axial length of the valve stop mechanism 20 can be further shortened.

FIG. 13 is a sectional view of a valve operating system 10 for an engine according to the sixth embodiment. As is clear from the figure,
The sixth embodiment differs from the first embodiment only in that a torsion bar spring is used as the spring 33 described above.

The torsion bar spring 33 is provided with a twisting portion 331 which is a fulcrum arranged at a corner of the upper inner body 24, and a swinging portion 332 which swings in the vertical direction in the figure with the twisting portion 331 as a fulcrum. . Swing part 33
2 extends from the twisted portion 331 toward the axis of the valve stop mechanism 20.

In the sixth embodiment, since the torsion bar spring is adopted as the spring 33, the compression space can be reduced as compared with the compression space of the coil spring. Therefore, the axial length of the valve stop mechanism 20 is shortened accordingly. can do.

14 and 15 are sectional views of the valve operating system 10 for an engine according to the seventh embodiment. As is clear from the figure, the sixth embodiment differs from the first embodiment only in that a torsion bar spring is adopted as the spring 45 for biasing the plate 34.

As shown in FIG. 15, the end of the torsion bar spring 45 is supported by the lower inner body 25. The torsion bar spring 45 includes a twisted portion 451 that serves as a fulcrum, and a swinging portion 452 that swings in the left-right direction in the drawing with the twisted portion 451 as a fulcrum.

In the seventh embodiment, since the torsion bar spring is used as the spring 45, as shown in FIG. 14, the coil spring is in the stem axial direction (the vertical direction in the drawing).
Since the occupied space can be reduced compared to the occupied space, the axial length of the valve stop mechanism 20 can be shortened accordingly.

[0084]

The invention of claim 1 has the following effects.

Since the second movable member that moves in the axial direction of the intake / exhaust valve is brought into contact with the stem tip portion, no load is applied to the stem tip portion in the direction orthogonal to the stem axis, and as a result, The uneven wear of the stem tip can be suppressed. Therefore, even if the stem is used for a long period of time, the tip of the stem is not scraped.

The invention of claim 2 has the following effects.

Since the slider is interposed between the stem and the third movable member moving in the directions orthogonal to each other so as to contact the stem, the stem tip portion and the third movable member do not come into contact with each other. The uneven wear of the stem tip can be suppressed. Therefore, even if the stem is used for a long period of time, the tip of the stem is not scraped.

The invention of claim 3 has the following effects.

Since the third movable member is a plate-shaped member,
Since the thickness of the movable member is reduced, the axial length of the valve stop mechanism can be shortened accordingly.

The invention of claim 4 has the following effects.

Since the guide groove formed on the slider is annular, the plate member can surely enter the guide groove even if the body and the slider rotate relative to each other. Further, since the opening width of the guide groove is made substantially the same as the thickness of the plate-shaped member, it is possible to prevent the plate-shaped member from rattling when the plate-shaped member enters the guide groove.

The invention of claim 5 has the following effects.

The slider is provided with a first flange portion extending in the axial direction of the body hole so that the lower surface thereof is along the upper surface of the guide groove, and the first flange portion is plated when the plate member is in the second position. Since the plate-shaped member is mounted on the plate-shaped member, it is possible to avoid interference between the plate-shaped member and the guide groove when the plate-shaped member moves from the second position to the first position, and to smoothly slide the plate-shaped member. It becomes possible to move. Further, when the plate-shaped member is in the second position, the slider can be prevented from falling to the outside, and when the plate-shaped member is in the second position, the slider can move to the third position.
The positioning with respect to the movable member is reliably performed.

The invention of claim 6 has the following effects.

Since the slider is provided with the guide portion for guiding the outer peripheral surface of the stem, the stem is prevented from interfering with the body and the third movable member, and the switchability of the relative movement regulation is improved and the stem and body are improved. Also, it is possible to suppress uneven wear of the third movable member.

The invention of claim 7 has the following effects.

Since the slider is provided with the second flange portion projecting upward from the upper surface of the slider guide hole so as to be always in contact with the outer peripheral surface of the slider guide hole, it is possible to suppress rattling when the slider slides.

The invention of claim 8 has the following effects.

Since the fourth spring for urging the body toward the cam is newly provided, the body can be always brought into contact with the cam even when the third movable member is in the second position.

When the third movable member is present at the second position, a third spring is newly provided which urges the slider toward the stem and makes the urging force smaller than the urging force of the first spring. Moreover, when the body moves to the cam side by the fourth spring, the slider can be prevented from floating up following it. As a result, when the third movable member is present at the second position, the slider is reliably positioned, so that the third movable member is moved to the second position.
It is possible to smoothly move from the position to the first position.

The invention of claim 9 has the following effects.

Since the third spring employs a tapered spring whose diameter decreases toward the tip thereof, the height of the spring itself can be made lower than that of a cylindrical spring. The axial length of the valve stop mechanism can be shortened.

The invention of claim 10 has the following effects.

Since the torsion bar spring is adopted as the third spring, the compression space can be reduced as compared with the compression space of the coil spring, and the axial length of the valve stopping mechanism can be shortened accordingly.

The invention of claim 11 has the following effects.

Since the torsion bar spring is adopted as the second spring, the space occupied by the coil spring in the axial direction of the stem can be reduced compared to the space occupied by the coil spring. Therefore, the axial length of the valve stopping mechanism can be shortened accordingly. You can

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a valve operating system for an engine (when an intake / exhaust valve is operating) according to a first embodiment.

FIG. 2 is a sectional view taken along line AA in FIG.

FIG. 3 is a cross-sectional view of a valve operating system for an engine (when intake and exhaust valves are at rest) according to the first embodiment.

4 is a sectional view taken along line BB in FIG.

FIG. 5 is an enlarged cross-sectional view of the slider and plate when the plate is in the second position and the cam contacts the valve stop mechanism at the base circle.

FIG. 6 is a cross-sectional view of a valve operating system for an engine (when an intake / exhaust valve is operating) according to a second embodiment.

7 is a cross-sectional view taken along line CC of FIG.

FIG. 8 is a cross-sectional view of a valve operating system for an engine (when intake and exhaust valves are at rest) according to a second embodiment.

9 is a sectional view taken along line DD in FIG.

FIG. 10 is a cross-sectional view of a valve operating system for an engine (when intake and exhaust valves are at rest) according to a third embodiment.

FIG. 11 is a cross-sectional view of a valve operating system for an engine (when intake and exhaust valves are at rest) according to a fourth embodiment.

FIG. 12 is a cross-sectional view of a valve operating system for an engine (when intake and exhaust valves are at rest) according to a fifth embodiment.

FIG. 13 is a cross-sectional view of a valve operating system for an engine according to a sixth embodiment (when the intake and exhaust valves are at rest).

FIG. 14 is a cross-sectional view of a valve operating system for an engine (when an intake / exhaust valve is operating) according to a seventh embodiment.

15 is a sectional view taken along line EE in FIG.

[Explanation of symbols]

 10 Engine Valve Device 11 Camshaft 12 Cam 13 Intake / Exhaust Valve 14 Valve Stem (Stem) 15 Cylinder Head 15a Cylinder Hole (Hole) 17 Valve Spring (First Spring) 20 Valve Stop Mechanism 21 Outer Body (First Movable Member) 24, 25 Inner body (first movable member) 26 Spring (fourth spring) 31 Body hole 32 Slider (second movable member) 321 Annular groove (movable member guide groove) 323 Flange portion (first flange portion) 324 Stem guide portion 33 spring (third spring) 34 plate (third movable member) 45 spring (second spring)

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koji Horita 2-1, Asahi-cho, Kariya city, Aichi Prefecture Aisin Seiki Co., Ltd. (72) Shinji Otsuka 2-chome, Asahi-cho, Kariya city, Aichi prefecture Address Aisin Seiki Co., Ltd. (72) Inventor Hiroyuki Kawai 2-chome, Asahi-cho, Kariya City, Aichi Aisin Seiki Co., Ltd.

Claims (11)

[Claims] 1. An intake / exhaust valve that opens and closes an intake hole or an exhaust hole that opens in a combustion chamber of an engine and is connected to a stem, and a first spring that urges the stem in a direction to close the intake / exhaust valve. A cam supported around a cam shaft, and a valve stop mechanism arranged between the cam and the stem, wherein the valve stop mechanism is provided in a hole formed in a cylinder head of an engine. A first movable member that is arranged so as to be movable in the axial direction of the intake / exhaust valve and contacts the cam; and a first movable member that is slidable in the hole in the axial direction of the intake / exhaust valve. A second movable member that is disposed so as to be relatively movable with respect to the stem distal end portion, and a relative movement restricting unit that can restrict relative movement between the first movable member and the second movable member. The engine's valve operating system. 2. The first movable member according to claim 1, wherein the first movable member is a body having a slider guide hole extending in the axial direction of the stem, and the second movable member is slidable in the slider guide hole. The relative movement restricting means is formed in the body and has a body hole having an axial center orthogonal to the axial center of the stem, and the body hole can be overlapped with the body hole in the slider. A guide groove formed in the guide hole, and a first position which is slidably disposed in the body hole and enters the guide groove by a hydraulic pressure applied to one end, and a second position which is removed from the guide groove. Third biased to position
A movable member, and urges the third movable member in a direction opposite to the hydraulic pressure, and moves the third movable member to the first and second positions when the hydraulic pressure is not acting on one end of the third movable member. A valve train for an engine having a second spring maintained in another position. 3. The engine valve operating system according to claim 2, wherein the third movable member is a plate-shaped member. 4. The engine movement according to claim 3, wherein the slider has a cylindrical shape, and the guide groove formed in the slider is an annular groove having an opening width substantially the same as the thickness of the plate member. Valve device. 5. The slider according to claim 3, wherein the slider is
The lower surface has a first flange portion extending in the axial direction of the body hole along the upper surface of the guide groove, and the first flange portion is provided when the plate-shaped member exists at the second position. A valve operating device for an engine mounted on the plate member. 6. The slider according to claim 2, wherein the slider is
An engine valve operating device having a guide portion for guiding the outer peripheral surface of the stem. 7. The slider according to claim 2, wherein the slider is
An engine valve operating device having a second flange portion projecting from the upper surface toward the cam so as to always contact the outer peripheral surface of the slider guide hole. 8. The valve stop mechanism according to claim 2,
A third spring that biases the slider toward the stem, the biasing force of which is smaller than the biasing force of the first spring; and a fourth spring that biases the body toward the cam. The engine's valve operating system. 9. The valve train for an engine according to claim 8, wherein the third spring is a tapered spring whose diameter is reduced toward the tip thereof. 10. The engine valve operating system according to claim 8, wherein the third spring is a torsion bar spring. 11. The engine valve operating system according to claim 2, wherein the second spring is a torsion bar spring.