JPH0749012A - Engine valve gear - Google Patents

Abstract

(57) [Summary] [Object] In a valve train of an engine having a rotation prevention plate and a rotation prevention groove for preventing rotation of a variable cylinder mechanism, a function as a variable cylinder is provided without increasing the axial length of the variable cylinder mechanism. To fulfill. A rotation preventing groove 58 is formed on the top of a slider 37 that sinks into the first and second bodies 30 and 32 by the lift amount of the cam 12 when the intake / exhaust valve 19 is closed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine valve operating system.

[0002]

2. Description of the Related Art A conventional engine valve operating system will be described with reference to FIG. The engine valve operating system 60 shown in FIG.
The high speed cam 12a and the low speed cams 13 and 14 supported around the cam shaft, the intake / exhaust valve 19, and the high speed cam 12a or the low speed cams 13 and 14 to engage and exhaust the exhaust valve 1
9 and a lifter 70 for adjusting the lift amount.

In the lifter 70, the cylinder head 18
A cup-shaped first body 30 is slidably arranged in the hole 21 formed in the first body 30, and a second body is arranged in the internal space 31 of the first body 30. The top surface of the second body 32 contacts the top and bottom surfaces of the first body 30,
A retainer 33 is fixed to the lower end of the with a snap 34. The stem end surface of the intake / exhaust valve 19 is in contact with the lower end surface of the retainer 33. The first body 30 and the second body 32 have holes 35 and 3 that overlap in the axial direction of the lifter 70.
6 are formed respectively, and a slider 59 is slidably arranged in the holes 35 and 36. Here, the opening widths of the holes 35 and 36 and the width of the slider 59 are the same as those of the high speed cam 12a. Incidentally, 39 indicates the lowermost end of the hole 36. A spring 38 is arranged between the lower end of the slider 59 and the retainer 33 to urge the slider 59 toward the high speed cam 12.

The second body 32 and the slider 59 have holes 40 and 41 which overlap in a direction perpendicular to the axial direction of the lifter 70.
And a pin 4 divided into three parts in the holes 40 and 41, respectively.
2, 43 and 61 are slidably arranged. here,
The length of the pin 43 is the same as that of the slider 59. Hole 40
Inside, a pressure chamber 45 is formed on the left side surface of the pin 42, and a spring chamber 46 is formed on the right side surface of the pin 42. The pressure chamber 45 is connected to the oil pan 48 via the passage 50, the concave groove 49, the passage 17 and the control valve 47, and is also connected to the oil pan 48 via the passage 50, the concave groove 49, the passage 17, the control valve 47 and the hydraulic pump 54. It is connected to the pan 48. On the other hand, the spring 52 is arranged in the spring chamber 46, and the pin 4 is arranged in the direction of decreasing the volume of the pressure chamber 45.
2,43,61 are urged. Here, when the left end of the pin 42 contacts the left end surface of the pressure chamber 45, the slider 5
9 and the pin 43 are designed to be completely polymerized. still,
Reference numeral 53 is a pressure release hole of the spring chamber 46.

A rotation preventing groove 51 is formed at the top of the first body 30 and the second body 32, and the camshaft 1 is positioned between the high speed cam 12a and the low speed cam 14.
A rotation prevention plate 15 is fixed around the circumference 1.
Regardless of the sliding position of the first body 30 and the second body 32, that is, whether the cams 12a, 13, 14 are in contact with the lifter 70 at the base circle or the cam surface, the rotation prevention plate 15 Is always engaged with the rotation preventing groove 51. This prevents the lifter 70 from rotating.

A retainer is fixed on the outer periphery of the stem of the intake / exhaust valve 19 via a cotter 55, and one end of a valve spring 57 is engaged with the retainer 56.

[0007]

When the above-mentioned lifter 70 is used as a variable cylinder, the low speed cams 13, 1 are used.
4 is unnecessary, but with the structure as it is, the rotation prevention plate 15 cannot enter below the state of FIG. 4,
Since the intake / exhaust valve 19 cannot be maintained in the closed state, the lifter 70 cannot function as a variable cylinder. Therefore, in order for the lifter 70 to function as a variable cylinder, the length L
Therefore, it is necessary to form the anti-rotation groove only deeply. However,
In the device 60 described above, the anti-rotation groove 51, which is constantly engaged with the anti-rotation plate 15, has the first body 30 and the second body 3.
Since the anti-rotation groove 51 is formed at the top of No. 2, the groove is formed at the top of the pin 42 or the bodies 30 and 32 are made long in the axial direction of the lifter 70 in order to form the anti-rotation groove 51 deeply by the length L. Must. Here, the pin 42 is in the axial direction of the lifter 70 (that is, the sliding direction of the bodies 30 and 32).
Since it moves in the vertical direction, it is impossible to form a groove on the top of the pin 42. On the other hand, body 3
When 0 and 32 are formed to be long in the axial direction of the lifter 70, it is not necessary to form a groove in the pin 42, but the axial length of the lifter 70 becomes long.

Therefore, according to the present invention, in a valve operating system of an engine having a rotation preventing plate and a rotation preventing groove for preventing the rotation of the lifter, the function as a variable cylinder can be achieved without increasing the axial length of the lifter. Is the technical issue.

[0009]

To solve the above technical problems, the technical measures taken in the present invention include a cam supported around a cam shaft and an opening / closing drive by the cam via a variable cylinder mechanism. A valve operating system for an engine having an intake and exhaust valve, the variable cylinder mechanism having a body hole formed in a direction perpendicular to an axial direction of the variable cylinder mechanism, and a hole formed in a cylinder head of an engine. A body arranged slidably in the axial direction of the variable cylinder mechanism, and a slider hole formed in a direction perpendicular to the axial direction of the variable cylinder mechanism and overlapping with the body hole when the intake / exhaust valve is opened, A slider that is slidably arranged in the axial direction of the variable cylinder mechanism inside the body and that can engage with the cam regardless of whether the intake / exhaust valve is operating or not, and a spring that biases the slider toward the cam. Possible in body hole It is slidably arranged in the direction perpendicular to the axial direction of the cylinder mechanism and prevents relative movement between the body and the slider by engaging with the body hole and the slider hole when the intake and exhaust valve is operated, and A first pin that is accommodated in the body hole when not operating and a first pin that is adjacent to the first pin in the body hole and is slidable in a direction perpendicular to the axial direction of the variable cylinder mechanism. By engaging with the hole and the slider hole, the relative movement between the body and the slider is prevented, and the second pin accommodated in the slider hole when the intake / exhaust valve is not operated is fixed to the camshaft so as to be adjacent to the cam. The anti-rotation plate and the anti-rotation groove formed on the top of the slider to prevent the rotation of the body by always engaging with the anti-rotation plate.

[0010]

The operation of the above technical means will be described.

When it is desired to stop the intake / exhaust valve at all times (that is, when the intake / exhaust valve is not in operation), the second pin overlaps with the slider hole, and when the slider engages with the cam, only the slider is moved according to the lift amount. It moves in the axial direction of the variable cylinder mechanism against the biasing force of the spring.

According to the above technical means, since the rotation preventing groove is formed at the top of the slider which operates as described above, the rotation preventing plate can be inserted in the moving direction of the slider. Therefore, since it is not necessary to form the rotation preventing groove in the body, it is not necessary to increase the axial length of the body, and it is not necessary to increase the axial length of the variable cylinder mechanism. Also, it is not necessary to form a groove in the first pin.

[0013]

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

An engine valve operating system 1 shown in FIGS. 1 and 2.
0, cylinder head 1 of the engine (not shown)
8, a cam shaft 11 is rotatably arranged, and one cam 12 is supported around the cam shaft 11 for one variable cylinder mechanism 20.

In the variable cylinder mechanism 20, a cup-shaped first body (body) 30 is slidably disposed in a hole 21 formed in the cylinder head 18, and the first body 30
A second body (body) 32 is disposed in the internal space 31 of the. The top surface of the second body 32 contacts the top and bottom surfaces of the first body 30, and the retainer 3 is attached to the lower end of the second body 32.
3 is fixed by a snap 34. The stem end surface of the intake / exhaust valve 19 is in contact with the lower end surface of the retainer 33. In the first body 30 and the second body 32, holes 35 and 36 that overlap in the axial direction of the variable cylinder mechanism 20 are formed, and a slider 37 is slidably arranged in the holes 35 and 36. Here, the upper end width of the slider 37 is the cam 1
It has the same width as 2. Incidentally, 39 indicates the lowermost end of the hole 36. A spring 38 is provided between the lower end of the slider 37 and the retainer 33, and the slider 37 is attached to the cam 12.
Is urged towards.

A body hole 40 is formed in the second body 32 in a direction perpendicular to the axial direction of the variable cylinder mechanism 20, and a slider hole 41, which can overlap the body hole 40, is also formed in the slider 37.
Are formed in a direction perpendicular to the axial direction of the variable cylinder mechanism 20. That is, the opening width of the body hole 40 is equal to the slider hole 4
Same as 1. A pin (first pin) 42, a pin (second pin) 43, and a pin 44, which are divided into three, are slidably arranged in the body hole 40. Here, the length of the pin 43 is substantially the same as the opening width of the holes 35 and 36. A pressure chamber 45 is formed on the left side surface of the pin 42 in the body hole 40,
A spring chamber 46 is formed on the right side surface of the pin 42. The pressure chamber 45 is connected to the oil pan 48 via the passage 50, the concave groove 49, the passage 17 and the control valve 47, and the oil pan via the passage 50, the concave groove 49, the passage 17, the control valve 47 and the hydraulic pump 54. Connected to 48. On the other hand, a spring 52 is arranged in the spring chamber 46, and the pins 42, 4 are arranged in the direction of decreasing the volume of the pressure chamber 45.
It is urging 3,44. Here, when the left end of the pin 42 contacts the left end surface of the pressure chamber 45, the slider 37 and the pin 43 are completely overlapped. Reference numeral 53 is a pressure release hole of the spring chamber 46.

A retainer is fixed on the outer circumference of the stem of the intake / exhaust valve 19 via a cotter 55, and one end of a valve spring 57 is engaged with the retainer 56.

Here, the characteristic portion of the present application will be described.

An anti-rotation groove 58 is provided on the top of the slider 37.
The rotation prevention plate 16 is fixed around the cam shaft 11 so as to be adjacent to the cam 12. Regardless of the sliding position of the first body 30 and the second body 32, that is, the cam 12 is the base circle, the variable cylinder mechanism 20.
The anti-rotation plate 16 is always engaged with the anti-rotation groove 58 regardless of whether it is in contact with the anti-rotation plate or the cam surface. This prevents the variable cylinder mechanism 20 from rotating.

The operation of the engine valve operating system 10 configured as described above will be described.

When the engine is started, the camshaft 11
Starts to rotate, and as a result, the cam 12 and the rotation prevention plate 16 are rotationally driven. First, when it is desired to operate the intake / exhaust valve 19, the control valve 47 is switched by the control means (not shown) as shown in FIG. 1, and the hydraulic pressure is changed by the hydraulic pump 54 via the passage 17, the concave groove 49 and the passage 50. It is supplied to the chamber 45. As a result, the pins 42, 43, 44 move in the right direction in the drawing against the biasing force of the spring 52, that is, in the direction of increasing the volume of the pressure chamber 45, and the pin 42 moves to the body hole 4.
0 and the slider 43 and straddle both of them 41
Extends over both the body hole 40 and the slider 41. As a result, the movement of the slider 37 into the holes 35 and 36 is blocked, and the first and second bodies 30 and 32 and the slider 3 are prevented.
Relative movement with 7 is prevented. Therefore, when the rotation of the cam 12 advances from the state where the cam 12 is in contact with the variable cylinder mechanism 20 on the base circle and starts to contact the slider 37 on the cam surface, the variable cylinder mechanism 20 begins to sink in the hole 21 in the axial direction. That is, while the slider 37 is engaged with the cam surface of the cam 12, the force is the slider 37 → the pins 42, 43 → the second
The body 32 → retainer 33 → the intake / exhaust valve 19 is transmitted, and the intake / exhaust valve 19 is connected to the valve spring 5 according to the lift amount of the cam surface.
7 moves downward in the drawing against the urging force of the intake / exhaust valve 19
Is separated from the seat surface (not shown) and intake or exhaust is performed. Here, the anti-rotation plate 16 always engages with the anti-rotation groove 58 regardless of the amount of depression in the hole 21 of the variable cylinder mechanism 20, and fulfills the anti-rotation function of the variable cylinder mechanism 20.

On the other hand, when it is desired to constantly stop the operation of the intake / exhaust valve 19, the control means (not shown) switches the control valve 47 as shown in FIG. The chamber 45 communicates with the oil pan 48 via the control valve 47. As a result, as shown in FIG.
2, 43 and 44 are moved to the left in the drawing by the urging force of the spring 52, that is, in the direction in which the volume of the pressure chamber 45 is reduced, and the pin 43 is substantially completely overlapped with the slider hole 41. This allows the slider 37 to slide within the holes 35 and 36. Therefore, the cam 12 has a base circle and the variable cylinder mechanism 20
When the rotation progresses from the state of being in contact with the slider 37 and the cam surface starts to contact with the slider 37, the slider 37 sinks in the downward direction in the figure against the spring 38 in the holes 35 and 36 according to the lift amount. That is, since the force of the cam 12 is not transmitted to the intake / exhaust valve 19, the intake / exhaust valve 19 is maintained in the closed state, that is, the state of being seated on the seat surface, and intake or exhaust is not performed. The maximum sinking position of the slider 37 is set so as not to reach the lowermost end 39 of the hole 36. Here, regardless of the amount of depression of the slider 37 in the holes 35 and 36, the rotation prevention plate 16 is provided with the rotation prevention groove 5
8 is always engaged with the variable cylinder mechanism 8 to prevent the variable cylinder mechanism 20 from rotating.

As shown above, in this embodiment,
Since the rotation preventing groove 58 is formed at the top of the slider 37 that sinks into the first and second bodies 30 and 32 by the lift amount of the cam 12 when the intake and exhaust valve 19 is not operated, the rotation preventing plate 16 is It becomes possible to enter the downward direction in the drawing, and the intake / exhaust valve 19 can be stopped at all times.

Therefore, since it is not necessary to form the rotation preventing groove 58 in the first and second bodies 30 and 32, it is not necessary to increase the axial length of the first and second bodies 30 and 32, and it is possible to change. It is not necessary to increase the axial length of the cylinder mechanism 20. Also, it is not necessary to form a groove in the first pin 42.

The engine valve operating system according to the present invention is
Although it is limited to the variable cylinder, it can also be applied to the variable lift.

[0026]

The present invention has the following effects.

In the valve operating system of the engine having the rotation preventing plate and the rotation preventing groove for preventing the rotation of the variable cylinder mechanism, it becomes possible to perform the function as the variable cylinder without increasing the axial length of the variable cylinder mechanism. .

[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 the present embodiment.

FIG. 2 is a cross-sectional view of a valve operating system for an engine (when intake and exhaust valves are stopped) according to the present embodiment.

FIG. 3 is a cross-sectional view of a valve operating system for an engine according to a conventional technique.

[Explanation of symbols]

 10 Engine Valve Device 11 Camshaft 12 Cam 16 Anti-Rotation Plate 19 Intake / Exhaust Valve 20 Variable Cylinder Mechanism 21 Hole 30 First Body (Body) 32 Second Body (Body) 37 Slider 38 Spring 40 Body Hole 41 Slider Hole 42 Pin (first pin) 43 pin (second pin) 58 Anti-rotation groove

Claims (1)

[Claims] 1. A valve operating device for an engine, which has a cam supported around a cam shaft, and an intake / exhaust valve that is driven to open / close by the cam via a variable cylinder mechanism, wherein the variable cylinder mechanism comprises: A body hole having a body hole formed in a direction perpendicular to the axial direction of the variable cylinder mechanism and slidably disposed in the axial direction of the variable cylinder mechanism in a hole formed in the cylinder head of the engine. And a slider hole formed in a direction perpendicular to the axial direction of the variable cylinder mechanism and overlapping with the body hole when the intake / exhaust valve is opened, and sliding in the axial direction of the variable cylinder mechanism inside the body. A slider that is freely arranged and that can engage with the cam regardless of whether the intake and exhaust valves are activated or deactivated, a spring that urges the slider toward the cam, and the variable cylinder in the body hole. mechanism Is slidably arranged in a direction perpendicular to the axial direction of the body, and prevents relative movement between the body and the slider by engaging with the body hole and the slider hole when the intake / exhaust valve operates, and A first pin accommodated in the body hole when the intake / exhaust valve is not operated, and a first pin that is adjacent to the first pin in the body hole and is slidable in a direction perpendicular to the axial direction of the variable cylinder mechanism. Engaging with the body hole and the slider hole when the intake / exhaust valve operates to prevent relative movement between the body and the slider, and accommodated in the slider hole when the intake / exhaust valve does not operate. A second pin, an anti-rotation plate fixed to the cam shaft so as to be adjacent to the cam, and an anti-rotation plate formed on the top of the slider and constantly engaged with the anti-rotation plate to prevent the body from moving. Valve operating device for an engine, characterized in that it is composed of a rotation preventing groove to prevent rotation.