JPH03267515A - Valve operating device of engine - Google Patents

Abstract

PURPOSE:To prevent defective lubrication of a lifter by protruding a bank wall forming an oil retainer groove around the lifter to a main locker arm. CONSTITUTION:A lost motion spring 7 is installed between a main locker arm 1 and sub-locker arm 3 for pressing the sub-locker arm 3 to a cam 23 for a high speed. A lifter 8 is installed between the lost motion spring 7 and sub locker arm 3 and is slidably fitted to the main locker arm 1. A pin 31 is enabled to lock the relative displacement of the sub-locker arm 3 in relation to the main locker arm 1. In this constitution, a bank wall 46 forming an oil retainer groove 44 around the lifter 8 is protrudedly provided to the main locker arm 1. By this constitution, the oil having lubricated cams 21 to 23 and the locker arm 1 and 3 is collected in the oil retainer groove 44 for preventing defective lubrication of the lifter 8.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an engine valve operating device, and particularly to an engine valve operating device that switches valve valve characteristics in accordance with engine operating conditions.

(Conventional technology) Conventionally, in order to achieve both torque during low- and medium-speed operation and improved output during high-speed operation, the lift characteristics of the intake valve or exhaust valve are varied depending on the operating condition, and this improves the intake and exhaust timing. Alternatively, it is known to control the amount of intake and exhaust (
For example, JP-A-63-167016, JP-A-63-
(See Publication No. 57805, etc.).

To explain this, a main rocker arm whose swinging tip contacts the valve, and a sub-rocker arm that is adjacent to one side of the main rocker arm and does not have a contact area with the valve are swingably supported on a common rocker shaft. A low-speed cam is in sliding contact with the main rocker arm, and a high-speed cam having a profile with a larger valve opening angle or valve lift amount than the low-speed cam is in sliding contact with the sub-rocker arm. A cost motion spring is provided that presses the high-speed rocker arm, which does not have a contact area with the valve, against the cam, and a rotor is inserted between the lost motion spring and the high-speed rocker arm and is slidably inserted into the shilling head. ing.

At the swinging part a predetermined distance away from the opening 7 lock 7F, in a direction parallel to the lock lock 7F, the two rocker arms are connected by a pin that responds to the hydraulic pressure fitting into or coming out of the fitting hole. or their bonds are broken.

(Problem to be Solved by the Invention) In such a conventional device, the lifter that receives the lost motion spring reciprocates at high speed following the high-speed rocker arm, but the sliding contact between this slide and the silling head is There was a problem in that there was insufficient supply of lubricating oil to the parts.

In addition, during high-speed operation when the low-speed rocker arm and the high-speed rocker arm swing together, it is necessary to strengthen the biasing force of the valve spring due to the increase in movable mass. There was a problem that the surface pressure acting on the sliding contact area increased, resulting in poor lubrication, increased combing resistance, and accelerated wear.

The present invention aims to solve these conventional problems.

(Means for Solving Problem 34) The present invention includes a main rocker arm that opens and closes an intake valve or an exhaust valve by following a cam having a profile in which at least one of the valve lift amount and the valve opening angle is relatively small. , a sub-rocker arm that is driven by a cam having a profile in which at least one of the valve opening amount and the valve opening angle is relatively large and is displaceable relative to the main rocker arm, and an intervening device between the main rocker arm and the sub-rocker arm. A lost motion spring is installed to press the sub rocker arm against the cam, and a lost motion spring is inserted between the lost motion spring and the sub rock arm and is slidably inserted into the main rocker arm. The main rocker arm is provided with a connecting drive means that can be locked, and a bank wall that defines an oil sump groove around the lifter is protruded from the main rocker arm.

Also, there is a notch that scatters the oil collected in the oil sump groove toward the sliding contact area between the intake valve or exhaust valve and the main rocker arm! was formed on the embankment wall.

(Function) When the main rocker arm and sub rocker arm swing together as one, the main rocker arm lifts off the cam, and the sub rocker arm follows the other cam, which has a relatively large profile, and opens the valve 1 jllff! drive

During operation in which the sub-rocker arm swings independently relative to the main rocker arm, the main rocker arm follows a cam with a relatively small profile to open and close the valve, while the sub-rocker arm is driven by the cam due to the biasing force of the lost motion spring. At this time, the lifter reciprocates within the sill part of the main rocker arm and transmits the biasing force of the lost motion spring to the sub rocker arm.

The lubricating oil supplied to each cam and each rocker arm flows down into the oil sump groove through the gap between the main rocker arm and the sub rocker arm, and is supplied from the oil sump groove to the sliding parts of the sub rocker arm and the 97ta.

The oil collected in the oil sump groove tries to scatter toward the swinging tip of the main rocker arm, but it is blocked by the embankment wall that protrudes around 1J7, so the oil can be effectively collected and the oil can be scattered. This makes it possible to keep the lifter's capacity small and reduce its wear.

In addition, by forming a notch in the embankment wall and scattering the oil collected in the oil sump groove from this notch as the main rocker arm swings toward the valve end and the sliding part of the main rocker arm. , lubricating oil is sufficiently supplied to the sliding part of the valve end, and even when the urging force of the pulp spring is strengthened in accordance with the speed ratio of the engine, 7 lux is kept small, and Reduces wear.

(Example) Fig. 1, Fig. 2, Fig. 3, and Fig. 4 show two valves (either an intake valve or an exhaust valve) having the same function for one cylinder. 1 shows an embodiment in which the present invention is applied to an engine equipped with

To explain this, each cylinder is provided with a single main rocker arm 1 corresponding to two intake valves 9. The base end of the main rocker arm 1 is swingably supported by the cylinder head via a main rocker shaft 12 common to each cylinder, and a shim 10 is attached to the top of the stem of each intake valve 9 at the tip of the main rocker arm 1. A pair of pulp follower portions IB are integrally formed and abut against each other via the pulp follower portions IB.

A loaf 7t lower 4 is rotatably connected to the main rocker arm 1 via a needle bearing 14 to a shaft 13, and a partial cam 21 is brought into rolling contact with this a-rough t lower 4.

The main locker 7-m 1 is formed into a roughly rectangular shape in a plan view,
Main rocker arm 1 has roller 7t along with lower 4.
Two sub-rocker arms 2.3 are provided. The base end of each sub-rocker arm 2, 3 is connected to the main rocker arm 1 via a sub-rocker shaft 16 so as to be able to move relative to each other.

Each of the sub-rocker arms 2 and 3 does not have a part that comes into contact with the intake valve 9, and each of the sub-rocker arms 2 and 3 has a lower part 2A and 3A with an arcuate cross section at the tip of the cam 7 that slides into contact with the low-speed cam 22 and the ^-speed cam 23. A motion spring 7 is provided below the cam 7 to press the lower portion 2A, 3A against each cam 22, 23.

As a connecting drive means that can lock the relative displacement of each rocker arm 2.3 with respect to the main rocker arm 1, each of the sub rocker arms 2, 3 has a main rocker shaft at a swinging portion separated from the main rocker shaft 12 by a predetermined distance. 7) In the direction parallel to 12, bins 31 and 32 are respectively interposed which respond to the hydraulic pressure. The main rocker arm 1 and each sub-rocker arm 2, 3 are connected to each other by fitting each pin 31, 32 into a fitting hole across the main rocker arm 1 and each sub-rocker arm 2, 3 while compressing each return spring 33. On the other hand, each bin 31, 32 is held in a predetermined position by the biasing force of the return spring 33, so that they are uncoupled from each other and swing independently.

Oil passages 34 and 35 for guiding the working oil pressure to each bottle 32 are provided through the main rocker shaft 12 and inside the main rocker 7-m 1. The oil pressure discharged from the oil pump is guided to the oil passages 34 and 35 under predetermined operating conditions via switching valves (not shown). A function that electronically controls the operation of the switching valve
- The unit inputs engine rotation signals, cooling water temperature signals, lubricating oil temperature signals, intake boost pressure signals from the supercharger, throttle valve opening signals, etc., and calculates engine torque based on these detected values. It is designed to smoothly switch between a partial cam 21, a low speed cam 22, and a high speed cam 23, which will be described later, while suppressing sudden fluctuations.

The partial cam 21, low-speed cam 22, and high-speed cam 23 are each integrally formed on the common camshaft 11, and satisfy the valve lift characteristics required during partial engine operation, high load, low rotation, and high rotation. They are formed in different shapes (including similar shapes with different sizes). Here, the valve 97F amount and the valve opening period are increased in the order of the partial cam 21, the low speed cam 22, and the high speed cam 23. As a result, the cam 21 with the lowest amount of 97 tons and a small valve opening period is used during partial load and idling operation to improve fuel efficiency, while the cam 21 with the lowest amount of 97 tons and a small valve opening period is used during partial load and idling operation, while the cam 21 with the lowest amount of 97 tons and a medium opening period is used during operation with a bulk load and low speed. Using the low speed cam 22 during the period, the high lift amount during commercial load ^ fast operation, and the high speed cam 2 during the large valve opening period.
Switch to 3 to make it compatible with output.

Inside the main rocker shaft 12, there is an oil passage 3 that supplies lubricating oil to the sliding portion of the main rocker arm 1.
6 is formed, and an oil supply pipe (not shown) that injects lubricating oil from above the camshaft 11 is provided to lubricate the valve train.

A cylindrical slide 8 is slidably provided between each lost motion control spring 7 and the main rocker arm 1.

Silling portions 25 and 26 are formed directly below each sub-rocker arm 2 and 3, and each silling portion 25 and 2
Each slot 8 is slidably inserted into the slot 6. A retainer 27 on which the lower end of each lost motion control spring 7 is seated is fastened to the main rocker arm 1 via two bolts 28. A stepped portion 8A is formed in each of the 97 ribs 8 to abut against the lower end of the silling portion 26 to prevent removal.

Each rocker 7-arm 2, 3 has a lower part 2B, 3B protruding with an arcuate cross-section onto which the top of each slide 8 slides, and each lifter 8 follows each rocker arm 2, 3. It is designed to move back and forth.

Embankment walls 45 and 46 defining oil sump grooves 43 and 44 having concave cross-sections are integrally formed around each of the main lockers 7-m 1, respectively.

Each bank wall 45, 46 protrudes in an annular shape connected to a cylindrical boss 841 into which the main rocker shaft 12 is fitted, and each oil sump groove 43, 44 has a C-shaped cross section between each bank wall 45, 46 and each lifter 8. are defined respectively.

The high-speed sub-rocker arm 3 is located approximately in the center of the two intake valves 9, and the embankment wall 46 located directly below the high-speed sub-rocker arm 3 has a right cylindrical shape concentric with the lifter 8. Protrude at a given height.

The low-speed sub-rocker arm 2 is arranged in parallel with one of the intake valves 9, and the embankment wall 45 located directly below the low-speed sub-rocker arm 2 is formed in a conical shape concentric with the slot 8 to reach a predetermined height. It stands out.

Furthermore, main rocker arm 1 has t! A notch 47 that opens at the swinging tip of the kMl 145 is formed.

This notch 47 is a bank! ! Main locker 7 for 45
- The center line of the notch 47, which opens at a position facing the pulp 7 lower part IB of the pulp 7 lower part IB in the plan view and is perpendicular to the main rocker shaft 12 in the plan view, is so arranged that it almost coincides with the center line of the pulp 7 lower part IB. will be placed in

Next, the effect will be explained.

During partial engine operation, the main rocker arm 1 swings according to the profile of the partial cam 21,
Ill each intake valve 9! ff! drive At this time, although each of the sub-rocker arms 2 and 3 is swung by each cam 22t23, each bin 31 and 32 is accommodated in a predetermined position due to the biasing force of each return spring 33, and the main rocker 7-m 1 is moved. do not interfere with

In this way, during operation in which each sub-rocker arm 2, 3 swings independently with respect to the main rocker arm 1, each sub-rocker arm 2.3 is pressed against each cam 22, 23 by the biasing force of each lost moshi spring 7. At this time, each 97 rig 8 reciprocates within each shilling fi 25, 26 and transmits the biasing force of each lost mosicon spring 7 to each sub rocker arm 2, 3.

Lubricating oil is injected upward from the camshaft 11 from an oil supply pipe (not shown) and lubricates each cam 21, 22, 23, and then passes through the gap between the main rocker arm 1 and each sub rocker arm 2, 3 to each sub rocker arm. Flowing down below the rocker arm 2.3, each sub rocker arm 2, 3 and each lifter 8
Each oil sump groove 43, 4 defined around each lifter 8 via the embankment walls 45, 46 while lubricating the sliding part with the top of the
Collected at 4.

Since each slide 8 swings around the main rocker shaft 12 together with the main rocker arm 1, oil tends to scatter from around each lifter 8 due to centrifugal force as the engine speed increases. Each oil sump groove 4 is blocked by embankment walls 25 and 26 that protrude around it.
It will be collected on 3.44.

The oil collected in each oil sump groove 43, 44 in this way is supplied to each silling part 25, 26 and the sliding part of each 7-star 8, keeping the 7 lux layer in this part small, Wear of each 97 rim 8 and each silling part 25*26 can be suppressed.

Bank! ! There is a notch in 45! 47 is open facing the pulp lower part IB of the main rocker arm 1, the oil collected in the oil sump groove 43 is scattered from the notch 47 toward the tip of the swing due to the swing of the main rocker arm 1. , the pulp 7a is supplied to the water section IB.

As a result, the pulp 7 year old lower part IB and the shim 1 of the intake valve 9
Even when the lubricating oil is sufficiently supplied to the sliding contact part with 0 and the urging force of the pulp spring 48 is strengthened in response to the increased speed of the ennon, the 79 comb 1 in this part is kept small. At the same time, wear of the pulp lower portion IB and the shim 10 can be suppressed.

When the engine is operating under high load, either one of the sub-rocker arms 2, 3 is connected to the main rocker 7-m 1 via each pin 31, 32 and swings together. In this case, since the partial cam 21 has a smaller valve opening amount and valve opening angle than the low speed cam 22 or the high speed cam 23, the lower 27 lower 4 is lifted from the partial cam 21, and each intake valve 9 Ill! according to the profile of slump cam 22 or commercial cam 23! ffi driven.

Because of the structure in which each sub-rocker arm 2゜3 is connected to the main rocker arm 1 via the sub-rocker shaft 16, the sub-rocker arm (high-speed rocker arm) and the main rocker arm (low-speed rocker arm) are connected to the common rocker shaft, as in conventional equipment. Each sub-rocker arm 2, 3 can be significantly miniaturized compared to a structure in which they fit together.

By reducing the size of each sub-rocker arm 2, 3, it becomes possible to make the biasing force of each lost force spring 7 relatively small, thereby suppressing the amount of fuel used and reducing the fuel consumption of the engine.

(Effects of the Invention) The present invention provides a loss-shielding spring that is interposed between an in-rocker arm and a sub-rocker arm and presses the sub-rocker arm against a cam, and a loss-shielding spring that is interposed between an in-rocker arm and a sub-rocker arm and presses the sub-rocker arm against a cam. The main rocker arm is provided with a slot into which it can be slidably inserted and a connecting drive means that can lock the relative displacement of the sub rocker arm with respect to the main rocker arm, and an oil sump groove is provided around the beam on the main rocker arm. Since the embankment wall is made to protrude, the oil that lubricates each cam and rocker arm is collected in the oil sump groove, thereby preventing poor lubrication of the slides.

In addition, since the oil collected in the oil sump groove is scattered from the notch in the embankment wall toward the sliding contact area between the intake valve or exhaust valve and the main rocker arm, lubricating oil is also applied to the sliding contact area at the valve end. The engine is supplied with a sufficient amount of fuel, making it possible to reduce the engine's fuel consumption by reducing the engine's fuel consumption and increase its durability.

In addition, by assembling the lost motion spring lifter 7 to the main rocker arm, these valve train systems can be made smaller, and the work efficiency during engine assembly and disassembly can be greatly improved. end.

[Brief explanation of drawings]

Fig. 1 is a plan view of a valve train showing an embodiment of the present invention, Fig. 2 is a cross-sectional view taken along line B-B# in the same figure, and Fig. vi3 is a cross-sectional view taken along line C-C in the same figure. , FIG. 4 is a longitudinal sectional view taken along the line D--D in the figure. 1- Main rocker arm, 2, 3... Sub-rocker arm, 7... Lost motion spring, 8...
・+J7F, 9...Intake valve, 12...Main rocker shaft, 16...Sub rocker shaft 7), 25.26
...Shilling part, 31.33-...Pin, 43.44
... Oil sump groove, 45.46 ... Embankment wall, 47 ... Notch.

Claims (1)

[Scope of Claims] 1. A main rocker arm that opens and closes an intake valve or an exhaust valve by following a cam having a profile in which at least one of the valve lift amount or the valve opening angle is relatively small; A sub-rocker arm that is driven by a cam and has a profile in which at least one of the valve angles is relatively large and is displaceable relative to the main rocker arm; and a sub-rocker arm that is interposed between the main rocker arm and the sub-rocker arm so that the sub-rocker arm is connected to the cam. A lost motion spring to press, a lifter interposed between the lost motion spring and the sub-rock arm and slidably fitted into the main rocker arm, and a connecting drive means capable of locking the relative displacement of the sub-rocker arm with respect to the main rocker arm. 1. A valve operating device for an engine, characterized in that the main rocker arm has a protruding embankment wall defining an oil sump groove around the lifter. 2. The engine valve operation according to claim 1, wherein a notch is formed in the embankment wall to scatter the oil collected in the oil sump groove toward the sliding contact portion between the intake valve or the exhaust valve and the main rocker arm. Device.