JP2015081513A - Valve gear of engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lubricate a contact part between a rocker arm and a valve stem more efficiently.SOLUTION: A valve train structure of an engine includes: a rocker arm supported by a support of the engine in a freely swingable manner; and a valve member in which an umbrella part contacting and separating with/from a valve hole of a valve is provided on one end of a shaft-shaped valve stem and the rocker arm contacts with an end face of a cap installed on the other end. The rocker arm includes a first oil supply hole passing through the rocker arm and whose opening faces the end face of the cap, and the cap includes a second oil supply hole passing through from an end face contacting with the rocker arm to an inner end face facing an end face of the other end of the valve stem. In the opening on a cap side of the first oil supply hole and the opening on a rocker-arm side of the second oil supply hole, the first oil supply hole and the second oil supply hole are positioned where they do not communicate with each other at the minimum lift when at least the umbrella part fully closes the valve hole.

Description

  The present invention relates to a valve operating apparatus for an engine that opens and closes an intake / exhaust valve.

  Conventionally, there is a structure using a rocker arm as a valve operating device for opening and closing an intake / exhaust valve of an engine.

  The rocker arm is swingably supported by a support portion provided in the cylinder head of the engine, and repeats rocking as the cam rotates.

  As the intake / exhaust valve, a valve (hereinafter referred to as a “valve member”) in which an umbrella portion, which is a valve body portion, is provided at one end of a shaft-shaped valve stem is used. The valve member is urged by a valve spring in a direction in which the umbrella portion closes the valve hole. The intake / exhaust valve opens and closes when the umbrella portion contacts and separates from the valve hole.

  The swinging end of the rocker arm is in contact with the other end of the valve stem, that is, the end face of the end opposite to the side where the umbrella is provided.

  When the rocker arm swings, the rocking end of the rocker arm moves toward the valve stem, and the other end of the valve stem is pressed against the urging force of the valve spring. Open the valve. Further, when the rocking end of the rocker arm moves away from the end of the valve stem, the valve member moves by the biasing force of the valve spring and closes the intake valve and the exhaust valve.

  Patent Document 1 discloses a technique in which a through hole for oil supply is provided at a rocking end of a rocker arm in order to oil lubricate a valve.

Japanese Patent Laid-Open No. 63-183407 (see FIGS. 12 and 13 in the drawings)

  According to Patent Document 1, the oil on the cylinder head side can be supplied to the valve side through the oil supply through hole provided in the rocker arm.

  However, the through-hole of the above-mentioned Patent Document 1 is provided in the rocker arm swinging end portion, particularly at a position sandwiching the side surface of the valve stem. The valve stem is not located directly below the oil supply hole, It falls to the combustion chamber side with almost no contact with the valve stem. For this reason, the function which lubricates the contact part of a rocker arm and a valve stem is not fulfilled. Since the abutting portion between the rocker arm and the valve stem is always in sliding contact with the rocker arm swinging, it is desirable that the rocker arm and the valve stem be efficiently lubricated to prevent wear. In particular, when a cap called an end cap is attached to the other end of the valve stem, it is desirable to efficiently lubricate the contact portion between the rocker arm and the cap, and between the cap and the valve stem.

  Accordingly, an object of the present invention is to more efficiently lubricate the contact portion between the rocker arm and the cap attached to the valve stem and the contact portion between the cap and the valve stem.

  In order to solve the above-described problems, the present invention is provided with a rocker arm that is swingably supported by a support portion of a cylinder head, and an umbrella portion that contacts and separates from a valve hole of a valve at one end of a shaft-shaped valve stem. In the valve operating structure of the engine provided with a valve member with which the rocker arm comes into contact with the end surface of the cap attached to the other end, the rocker arm penetrates the rocker arm and the opening faces the end surface of the cap. A first oil supply hole, and the cap includes a second oil supply hole penetrating from an end surface with which the rocker arm abuts to an inner end surface facing the other end surface of the valve stem, and the cap of the first oil supply hole The opening on the cap side and the opening on the rocker arm side of the second oil supply hole are at least a minimum lift when the umbrella portion completely closes the valve hole, and the first oil supply hole and the second oil supply hole Two oil supply and holes are adopted a configuration in which a position not in communication with each other.

  At this time, at the time of the minimum lift in which the umbrella portion completely closes the valve hole, the opening on the cap side of the first oil supply hole and the opening on the rocker arm side of the second oil supply hole are at the time of the minimum lift. A configuration may be employed that is located between a contact point between the rocker arm and the end surface of the cap and a contact point between the rocker arm and the end surface of the cap at the time of maximum lift.

  In addition, the cap-side opening of the first oil supply hole and the rocker arm-side opening of the second oil supply hole are at least at the minimum lift when the umbrella portion completely closes the valve hole. A configuration in a position eccentric from the axis can be employed.

  At this time, when the other end of the shaft center of the valve stem is inclined in one direction with respect to the one end, the opening on the cap side of the first oil supply hole extends from the shaft center of the valve stem. A configuration that faces the end face of the cap at a position eccentric to the other side can be employed.

  Further, at this time, the amount of eccentricity of the opening on the cap side of the first oil supply hole from the axis of the valve stem at the time of the minimum lift is equal to the rocker arm side of the second oil supply hole at the time of the minimum lift. It is desirable that the opening be set larger than the amount of eccentricity from the axis of the valve stem.

  In each of these aspects, it is possible to adopt a configuration in which the first oil supply hole and the second oil supply hole or any one of the inner surfaces are tapered holes that gradually become narrower toward the valve stem side.

  According to the present invention, the first oiling hole that penetrates the rocker arm and whose opening faces the end surface of the cap is provided in the rocker arm. Since the second oil supply hole penetrating to the inner end surface facing the end surface is provided, the contact portion between the rocker arm and the cap attached to the valve stem, and the contact portion between the cap and the valve stem, respectively, Lubricating can be performed more efficiently.

  In addition, since the opening on the cap side of the first oil supply hole and the opening on the rocker arm side of the second oil supply hole are set at positions where the first oil supply hole and the second oil supply hole do not communicate with each other at least during the minimum lift, The oil does not enter the second oil supply hole directly from the first oil supply hole, and moves from the first oil supply hole along the end surface of the cap and then reaches the second oil supply hole. For this reason, the end surface of the cap can be more efficiently lubricated.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front sectional view showing an engine valve operating apparatus according to an embodiment of the present invention. The rocker arm used for the valve gear of the engine of the embodiment is shown, (a) is a front view, (b) is a plan view. It is a principal part enlarged view which shows the contact part of a rocker arm and a valve stem. It is a principal part enlarged view which shows the contact part of a rocker arm and a valve stem. (A) (b) is a top view which shows the positional relationship of the 1st oil supply hole by the side of a rocker arm, and the 2nd oil supply hole by the side of a cap. The rocker arm used for the valve gear of the engine of other embodiments is shown, (a) is a front view and (b) is a top view.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. This embodiment is a valve gear 10 for an automobile engine. In the drawings, only members and means directly related to the present invention are shown, and other members and the like are not shown. Although only one cylinder 1 is shown in the drawings, the engine may be a single cylinder or a multi-cylinder having a plurality of cylinders 1.

  As shown in FIG. 1, the cylinder 1 is provided with an intake port 3 communicating with the combustion chamber 2 and a valve 5 (hereinafter referred to as “valve member 5”) for opening and closing the valve hole 4 of the intake port 3. Yes. A fuel injection device (not shown) for injecting fuel into the intake port 3 is provided in the intake port 3, and fuel is injected into the intake air in the intake port 3 to form an air-fuel mixture. Hereinafter, the valve gear 10 of the engine will be described by taking the intake port 3 as an example, but the same structure can be adopted also in the exhaust port. The engine is not limited to the fuel injection device provided in the intake port 3, but is provided in the combustion chamber 2 to inject fuel into the intake air in the combustion chamber 2 to form an air-fuel mixture. An injection engine may be used.

  As shown in FIG. 1, the valve gear 10 includes a valve member 5 and an elastic member 6 (hereinafter referred to as “valve spring 6”) that urges the valve member 5 in the valve closing direction of the valve hole 4. And a rocker arm 20 that is swingably supported by a support portion 11 provided in the cylinder 1 of the engine. The valve stem 5b is inserted into a valve insertion hole 5d formed in the cylinder 1 via a cylindrical valve stem guide 5c, and is movable back and forth in the axial direction with respect to the cylinder 1.

  The lower end of the valve spring 6, that is, the end close to the combustion chamber 2 is supported by the cylinder 1 via the valve spring seat 6a, and the upper end, that is, the end on the cylinder head side, is the retainer 6b and the cotter. It is fixed to the valve stem 5b via 6c. The retainer 6b is an annular member, and supports the upper end of the valve spring 6 at the outer periphery thereof. A valve stem 5b is inserted through the inner periphery of the retainer 6b via a cotter 6c.

  The cotter 6c is a split collet that is divided in half with the outer peripheral surface being a conical surface. The cotter 6c is in surface contact with the inner peripheral surface of the retainer 6b, which is also formed of a conical surface, and the outer peripheral surface of the valve stem 5b, and fixes the valve stem 5b and the retainer 6b. At this time, a retaining protrusion 6d is provided on the inner surface of the cotter 6c, and the retaining protrusion 6d enters the retaining recess 5e formed on the outer peripheral surface of the valve stem 5b to provide a retaining function in the axial direction. Demonstrate.

  In this embodiment, the valve stem 5b cannot rotate about the axis relative to the cotter 6c and the retainer 6b. However, the valve stem 5b can rotate relative to the axis relative to the cotter 6c and the retainer 6b. In some cases, a supporting structure is adopted.

  As shown in FIG. 2, the rocker arm 20 includes a longitudinal body member 20c formed by pressing or the like from the support end portion 20a to the swing end portion 20b, and is located in the middle in the longitudinal direction of the body member 20c. The roller 21 is slidably brought into contact with the cam 30 and functions as a power point. The roller 21 is rotatably supported by the main body member 20c by a support shaft 21a.

The support end portion 20a is provided with a fulcrum member 25 that fits into a recess of the support portion 11 provided on the cylinder 1 side and supports the rocker arm 20 so as to be swingable. In this embodiment, the inner surface of the concave portion of the support portion 11 is a spherical surface, and the outer surface of the fulcrum member 25 is a spherical surface that is slidably in contact with the inner surface of the concave portion. The end portion 20b swings up and down.
The fulcrum member 25 is fixed to the main body member 20c by a bolt 26 integral with the fulcrum member 25 being inserted into a hole provided in the main body member 20c and fastened by a nut 27 to be integrated.

  The valve member 5 is provided with an umbrella portion 5a that functions as a valve body portion that contacts and separates from the valve hole 4 at one end a of a shaft-shaped valve stem 5b. Further, the other end b of the valve stem 5 b extends to the rocking end 20 b of the rocker arm 2.

  An abutting member 25 that abuts against the other end b of the valve stem 5 b is provided at the rocking end 20 b of the rocker arm 20. The lower surface 24 of the contact member 25 is a slipper surface. The contact member 25 may be formed separately from the rocker arm 20 or may be integrally formed of the same material.

  In this embodiment, a metal concave cap 7 called an end cap is fitted to the other end b of the valve stem 5b. For this reason, the lower surface 24 of the contact member 25 of the rocker arm 20 contacts the end surface of the cap 7 of the valve stem 5b. That is, the lower surface 24 of the contact member 25 makes point contact with the end surface of the cap 7. The cap 7 is provided with an end surface member 7a that is circular in plan view and forms the end surface, and a cylindrical peripheral wall portion 7b that rises from the periphery of the end surface member 7a toward the opposite side of the end surface over the entire circumference.

  When the cam 30 rotates together with the cam shaft 31 around the cam shaft 31, a pressing force acts on the roller 21 from the cam surface 30 a of the cam 30. By the action of the cam 30, the rocker arm 20 moves up and down in a direction connecting the cylinder head side and the combustion chamber 2 side with the support end portion 20a serving as a fulcrum.

  At this time, if the contact member 25 is lowered, the lower surface 24 of the contact member 25 presses the other end b of the valve stem 5b against the elastic force of the valve spring 6, and the valve member 5 is lowered and the valve The hole 4 is opened. When the contact member 25 is raised, the valve member 5 is raised by the elastic force of the valve spring 6 to close the valve hole 4. In this manner, the valve member 5 opens and closes the intake port 3 at a predetermined timing by the rotation of the cam 30 and the swing of the rocker arm 20 associated therewith.

  The transmission of power to the camshaft 31 is performed by connecting a sprocket provided on the camshaft 31 side and a sprocket provided on the crankshaft side with a timing chain or the like.

  Here, the contact member 25 of the rocker arm 20 is provided with a first oil supply hole 22 that passes through the rocker arm 20 and faces the end surface of the cap 7.

  As shown in FIG. 3, the opening of the first oil supply hole 22 on the valve stem 5b side faces the end surface of the cap 7 at a position m eccentric from the axis c of the valve stem 5b. The position m is the intersection of the center line d of the first oil supply hole 22 having a circular cross section and the end surface of the cap 7. FIG. 3 shows how the umbrella portion 5a is at the minimum lift when the valve hole 4 is completely closed. Reference sign p is a contact point of the rocker arm 20 at the time of the minimum lift.

  By providing the first oil supply hole 22, the contact portion between the rocker arm 20 and the end surface of the cap 7 can be more efficiently lubricated not only in the vicinity of the axis c but also over the entire end surface. Further, since the cap 7 is rotatable around the axis c of the valve stem 5b, the oil easily reaches the entire end face with the rotation.

  Further, the cap 7 is provided with a second oil supply hole 8 penetrating from an end face with which the rocker arm 20 abuts to an inner end face facing the end face of the other end b of the valve stem 5b. The second oil supply hole 8 is provided through the end face member 7 a of the cap 7.

  As shown in FIG. 3, the opening on the rocker arm 20 side of the second oil supply hole 8 faces the end surface of the cap 7 at a position r eccentric from the axis c of the valve stem 5b. The position r is the intersection of the center line e of the second oil supply hole 8 and the end surface of the cap 7.

  As shown in FIG. 3, the opening on the cap 7 side of the first oil supply hole 22 and the opening on the rocker arm 20 side of the second oil supply hole 8 are at least during the minimum lift, the first oil supply hole 22 and the second oil supply hole 8. Are set so that they are not in communication with each other. The center line d of the first oil supply hole 22 and the center line e of the second oil supply hole 8 are in a positional relationship shifted with respect to the planar direction of the end face.

  Further, as shown in FIG. 5 (a), the amount of eccentricity from the shaft center c of the valve stem 5b of the opening on the cap 7 side of the first oil supply hole 22 at the time of the minimum lift is the same as the second oil supply hole at the time of the minimum lift. 8 is set larger than the amount of eccentricity from the axis c of the valve stem 5b of the opening on the rocker arm 20 side. As shown in FIG. 5B, the amount of eccentricity from the shaft center c of the valve stem 5b of the opening on the cap 7 side of the first oil supply hole 22 at the time of the minimum lift is the same as the second oil supply hole at the time of the minimum lift. It is also possible to set the opening on the side of the rocker arm 20 side of 8 smaller than the amount of eccentricity from the axis c of the valve stem 5b.

  As shown in FIG. 1, the camshaft 31 that swings the rocker arm 20 is lubricated by oil injected from a first oil supply portion 32 a provided in an oil pipe 32 provided above the camshaft 31. Yes.

  The oil pipe 32 is provided with a second oil supply part 32 b that injects oil toward the first oil supply hole 22 of the rocker arm 20. By providing the second oil supply part 32b, the supply of oil to the oil supply hole 22 of the rocker arm 20 can be sufficiently ensured. In this embodiment, the first oil supply part 32 a is a downward hole provided in the oil pipe 32 and directed to the cam 30, whereas the second oil supply part 32 b is directed to the oil supply hole 22 of the rocker arm 20. It consists of a laterally or diagonally downward hole.

  Further, the rocking end 20b of the rocker arm 20 is provided with a concave oil reservoir 23 on the upper surface thereof, that is, the surface opposite to the side facing the valve stem 5b. Further, the first oil supply hole 22 opens into the oil reservoir 23. For this reason, the oil can be smoothly supplied to the first oil supply hole 22 and the valve stem 5b. The installation of the oil reservoir 23 can be omitted.

  As shown in FIG. 1, the shaft center c of the valve stem 5 b is inclined such that the other end b of the valve stem 5 b is unidirectional with respect to the one end a, that is, the support end 20 a side of the rocker arm 20. This inclination corresponds to an angle α with respect to the vertical direction.

  The opening on the cap 7 side of the first oil supply hole 22 is formed on the end surface of the cap 7 at a position deviated from the axis c of the valve stem 5b in the other direction, that is, away from the support end 20a of the rocker arm 20. I'm here. Since the end surface of the cap 7 is configured by a plane orthogonal to the axis c, the plane has an upward slope of an elevation angle α from the one direction side toward the other direction side.

  Here, the position where the opening of the first oil supply hole 22 is decentered from the axis c of the valve stem 5b to the side opposite to the inclination direction of the axis c, that is, to the upper side of the upward slope of the end face (the other direction side). Therefore, since the oil has faced the end surface, the oil that has passed through the first oil supply hole 22 easily reaches the entire end surface of the cap 7 that is a contact surface with the rocker arm 20.

  Further, both the opening on the rocker arm 20 side and the opening on the valve stem 5b side of the second oil supply hole 8 face the end face and the inner end face of the cap 7 at a position eccentric from the axis c of the valve stem 5b. Since the cap 7 is rotatably fitted around the axis c of the valve stem 5b, the second oil supply hole 8 is eccentric from the axis c of the valve stem 5b to the side farther from the support end 20a of the rocker arm 20. At this position, an opportunity to face the end surface of the other end b of the valve stem 5b occurs. Since the end surface of the other end b of the valve stem 5b is constituted by a plane orthogonal to the axis c, the plane is an upward gradient from one direction side to the other direction side.

  Here, with the rotation of the cap 7, the opening on the rocker arm 20 side and the opening on the valve stem 5b side of the second oil supply hole 8 are opposite to the inclination direction of the axis c from the axis c of the valve stem 5b. If the oil reaches a position deviated upward (in the other direction) of the upward slope of the end surface, the oil that has passed through the second oil supply hole 8 is the entire inner end surface of the cap 7 that is a contact surface with the valve stem 5b, And it is easy to reach the entire end face of the other end b of the valve stem 5b.

  During the minimum lift, the rocking end 20b of the rocker arm 20 is positioned relatively upward, and the rocking end 20b is close to the oil pipe 32 provided above the cam 30. For this reason, at least during the minimum lift at which oil is easily supplied, the opening of the first oil supply hole 22 is eccentric from the axis c of the valve stem 5b to the other direction, that is, the side farther from the support end 20a of the rocker arm 20. It is desirable to face the end surface of the cap 7 at the position.

  At this time, the amount of eccentricity from the axis c of the valve stem 5b of the opening on the cap 7 side of the first oil supply hole 22 at the time of the minimum lift is the same as that on the rocker arm 20 side of the second oil supply hole 8 at the time of the minimum lift. It is desirable that the opening is set to be larger than the amount of eccentricity from the axis of the valve stem 5b. By providing such a difference in the amount of eccentricity, it is possible to secure a path through which the oil flows smoothly from the upper side to the lower side in the order of the first oil supply hole 22, the end face of the cap 7, and the second oil supply hole 8. Because.

  FIG. 4 shows the position of the opening on the cap 7 side of the first oil supply hole 22 at the time of the minimum lift as compared to the contact point p between the rocker arm 20 and the end surface of the cap 7 at the time of the minimum lift. It is located at a position closer to the lower side and higher than the axis c of the valve stem 5b (see point m). At the maximum lift, the contact point q with the end face of the cap 7 moves toward the lower side of the gradient. The point where the opening of the first oil supply hole 22 faces the end surface at the time of the maximum lift is a point indicated by reference sign n. The position indicated by the symbol n is the intersection of the center line d of the first oil supply hole 22 and the end surface of the cap 7.

Since the opening of the first oil supply hole 22 on the cap 7 side is positioned at an upper side of the gradient than the axis c of the valve stem 5b at least during the minimum lift, sufficient oil lubrication is possible.
Further, at the time of the minimum lift in which the oil is sufficiently supplied, the opening on the cap 7 side of the first oil supply hole 22 and the opening on the rocker arm 20 side of the second oil supply hole 8 are connected to each other between the rocker arm 20 and the cap 7 at the time of the minimum lift. Since it is disposed between the contact point p with the end surface and the contact point q between the rocker arm 20 and the end surface of the cap 7 at the time of the maximum lift, two points p that are the sliding contact range between the rocker arm 20 and the cap 7, The space between q can be efficiently lubricated. The cap 7 is rotatable around the axis c of the valve stem 5b, but the opening on the rocker arm 20 side and the opening on the valve stem 5b side of the second oil supply hole 8 are located between the two points p and q. It is desirable to do. Alternatively, it is desirable that the time between the two points p and q is as long as possible.

  Further, the position of the opening of the first oil supply hole 22 toward the cap 7 at the time of the minimum lift is higher than the contact point p between the rocker arm 20 and the end surface of the cap 7 at the time of the minimum lift. It is also possible to adopt a configuration that faces the side.

  In this configuration, since the opening of the oil supply hole 22 is always located closer to the upper end of the end surface gradient than the contact point between the rocker arm 20 and the end surface of the cap 7, the oil flows down by its own weight along the gradient. Sufficient oil lubrication is possible.

In addition, the inclination of the axis c of the valve stem 5b and the end surface of the other end b of the valve stem 5b are the same as those on the cap 7 side of the first oil supply hole 22 even in an engine in which the inclination of the end surface of the cap 7 is not set. If the opening faces the end surface of the cap 7 at a position deviated from the axis c of the valve stem 5b, an effect of promoting the supply of oil to the abutting portions of both can be expected.
If the opening on the rocker arm 20 side and the opening on the valve stem 5b side of the second oil supply hole 8 are eccentric from the axis c of the valve stem 5b, the cap 7 can rotate around the axis c of the valve stem 5b. Therefore, a high lubrication effect can be expected over a wide range of the end surface of the other end b of the valve stem 5b and the inner end surface of the cap 7 slidably in contact therewith.

  As described above, the opening on the cap 7 side of the first oil supply hole 22 and the opening on the rocker arm 20 side of the second oil supply hole 8 are such that the first oil supply hole 22 and the second oil supply hole 8 are mutually connected at least during the minimum lift. It is desirable to be in a position that does not communicate. However, even if the first oil supply hole 22 and the second oil supply hole 8 are temporarily communicated with each other, it is possible to exert a predetermined lubrication performance on each sliding contact portion if they are not always communicated.

  Further, at least during the minimum lift, the opening on the cap 7 side of the first oil supply hole 22 and the opening on the rocker arm 20 side of the second oil supply hole 8 are the contact points between the rocker arm 20 and the end face of the cap 7 during the minimum lift. It is desirable to be located between p and the contact point q between the rocker arm 20 and the end face of the cap 7 at the time of maximum lift. Also, at least during the minimum lift, the opening of the second oil supply hole 8 on the valve stem 5b side is also the contact point p between the rocker arm 20 and the end face of the cap 7 during the minimum lift, and the rocker arm 20 and the cap 7 during the maximum lift. It is desirable that it is located between the contact point q with the end face of.

  Furthermore, it is desirable that the opening on the cap 7 side of the first oil supply hole 22 and the opening on the rocker arm side of the second oil supply hole 8 are at positions eccentric from the axis c of the valve stem 5b at least during the minimum lift. Also, at least during the minimum lift, it is desirable that the opening of the second oil supply hole 8 on the valve stem 5b side is also in a position eccentric from the axis c of the valve stem 5b.

  FIG. 6 shows the inner surface of the first oil supply hole 22 from the opening to the cylinder head side, that is, the surface opposite to the side facing the valve stem 5b, to the combustion chamber 2 side, that is, the valve stem 5b side. The taper hole gradually narrows toward the opening.

  By making the inner surface shape of the first oil supply port 22 into a tapered hole that gradually narrows toward the valve stem 5b side, the oil can be easily guided to the oil supply hole 22, and the contact portion with the cap 7 can be made more efficient. It becomes possible to lubricate.

  Moreover, the inner surface shape of the second oil supply hole 8 can also be a tapered hole gradually narrowing toward the valve stem 5b. As a result, the oil is easily guided to the second oil supply hole 8, and the contact portion with the valve stem 5b can be more efficiently lubricated.

  Further, by adopting the tapered hole, when the rocker arm 20 is lifted, that is, when the rocker arm 20 returns from the position corresponding to the maximum lift of the valve to the position corresponding to the minimum lift, the rocker arm 20 is swung. The accompanying inertia force works, and the oil in the oil supply hole 22 can be discharged toward the valve stem 5b without leaving any oil.

1 Cylinder 2 Combustion chamber 3 Intake port 4 Valve hole 5 Valve member (valve)
5a Umbrella part 5b Valve stem 6 Valve spring 7 Cap 8 Second oil supply hole 10 Valve operating device 11 Support part 20 Rocker arm 21 Roller 22 First oil supply hole 23 Oil reservoir 24 Lower surface 25 Contact member 30 Cam 31 Cam shaft 32 Oil pipe

Claims (6)

A rocker arm that is swingably supported by the support portion of the cylinder head;
In a valve operating structure for an engine, comprising an umbrella portion provided at one end of a shaft-shaped valve stem, and a valve member abutting against an end surface of a cap attached to the other end of the cap, the valve member being in contact with the valve hole.
The rocker arm includes a first oiling hole that penetrates the rocker arm and whose opening faces the end surface of the cap.
The cap includes a second oil supply hole penetrating from an end surface with which the rocker arm abuts to an inner end surface facing the other end surface of the valve stem,
The opening on the cap side of the first oil supply hole and the opening on the rocker arm side of the second oil supply hole are at least in the minimum lift when the umbrella portion completely closes the valve hole. A valve operating apparatus for an engine, wherein the second oil supply hole is in a position not communicating with each other.   At the time of the minimum lift when the umbrella portion completely closes the valve hole, the opening on the cap side of the first oil supply hole and the opening on the rocker arm side of the second oil supply hole are the rocker arm at the time of the minimum lift. 2. The engine valve operating device according to claim 1, wherein the engine valve position device is located between a contact point between the end face of the cap and the end face of the cap and a contact point between the rocker arm and the end face of the cap at the time of maximum lift.   The opening on the cap side of the first oil supply hole and the opening on the rocker arm side of the second oil supply hole are respectively the axis centers of the valve stems at least during the minimum lift when the umbrella portion completely closes the valve hole. The valve operating apparatus for an engine according to claim 1 or 2, wherein the valve operating apparatus is in an eccentric position.   The valve stem has an axial center whose other end is inclined in one direction with respect to the one end, and the cap-side opening of the first oil supply hole is decentered from the axial center of the valve stem to the other side. 4. The valve gear for an engine according to claim 3, which faces the end face of the cap.   The amount of eccentricity of the opening on the cap side of the first oil supply hole from the axial center of the valve stem during the minimum lift is the valve stem of the opening on the rocker arm side of the second oil supply hole during the minimum lift. The valve operating apparatus for an engine according to claim 4, wherein the valve operating apparatus is set to be larger than an eccentric amount from the shaft center of the engine.   6. The method according to claim 1, wherein the first oil supply hole and the second oil supply hole or any one of the inner surfaces is a tapered hole that gradually narrows toward the valve stem side. The valve operating device for the engine described.

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