JPH0541802B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a control device for a valve operation stop mechanism.

For example, a multi-cylinder engine has two intake valves (main and auxiliary) per cylinder, and when the load is low or medium, the auxiliary intake valve is stopped and only the main intake valve is operated, and when the load is high, the output is increased. There are some that operate both main and sub intake valves for this purpose. In addition, depending on the operating state, for example, when idling or under low load, it is not necessary to operate all cylinders, so in order to save fuel consumption, the intake and exhaust valves of some cylinders are stopped and the cylinders are deactivated. Accordingly, it is being considered to operate the intake and exhaust valves again to operate all cylinders. As a mechanism for operating and stopping the above-mentioned valve, for example, as shown in Figure 6 of British Patent No. 2075118A, a removable stopper is provided between the rocker arm body and the plunger that constitute the transmission member of the valve train. However, it has been proposed that the stopper is driven by a hydraulic actuator.

However, when equipped with a hydraulic actuator in this way and switching between activation and stop (non-activation) of the valve based on the supply and discharge of hydraulic pressure to the hydraulic actuator, it is necessary to When the hydraulic pressure supplied to the hydraulic actuator decreases, it becomes difficult for the hydraulic actuator to keep the stopper in place, and the stopper engages with the plunger in an incomplete position, causing the dynamic engagement part to There was a risk that abnormally high stress, which could lead to damage, would occur or noise would be generated.

The present invention has been proposed in view of the above, and includes:
In a valve operation stop mechanism that stops the operation of intake and exhaust valves of an engine according to operating conditions, between a first position in which the intake and exhaust valves are activated and a second position in which the operation of the intake and exhaust valves is stopped. A movable member disposed movably, a biasing member that biases the movable member toward either the first position or the second position, and a biasing member that engages with the movable member. a hydraulic actuator that holds the movable member at the other of the first position or the second position against the biasing force of the biasing member when hydraulic pressure is supplied; a hydraulic pressure supply means for supplying the hydraulic pressure, a hydraulic pressure supply control means for controlling the supply of hydraulic pressure to the hydraulic actuator by the hydraulic pressure supply means, a hydraulic pressure drop detection means for detecting a state of decrease in the hydraulic pressure supplied to the hydraulic actuator, and the engine. A control signal is supplied to the hydraulic pressure supply control means so that the hydraulic pressure is removed from the hydraulic actuator when the hydraulic pressure drop detection means detects a reduced state of the hydraulic pressure during operation other than starting. The gist of the present invention is a control device for a valve operation/stop mechanism, which is characterized by being equipped with actuator control means.

Hereinafter, one embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 to 5, a four-cylinder engine 10 for an automobile has a cylinder head 12 and a cylinder block 14, and pistons 16a, 16b, which are connected to a crankshaft (not shown) via a connecting rod.
16c and 16d are respectively arranged to form four combustion chambers 18a, 18b, 18c and 18d. Each combustion chamber 18a, 18b, 18c, 18
d, each of the main intake ports 20a, 20b, 20c, and 20d, which are independent from each other and have a relatively small cross-sectional area, and the sub-intake ports 22a, 22b, 22c, and 22d that have a larger cross-sectional area than each of the main intake ports are communicated with each other, Each of these ports has a main intake valve 24.
a, 24b, 24c, 24d and sub-intake valve 26
a, 26b, 26c, and 26d are interposed.
Each main intake port 20a, 20b, 20c, 20d
have one end open to one side of the cylinder head 12, and the other end open to each combustion chamber 18a, 18b, 18.
It opens into each of the combustion chambers so that the center of the passage is located on one side of the plane containing the cylinder axis of cylinders c and 18d, and the port center lines near the other end opening of each of the main intake ports correspond to each other. Each of the main intake ports 20a, 2 is oriented in a direction that does not intersect with or parallel to the cylinder axis of the combustion chamber.
Each combustion chamber 18a, 18 from 0b, 20c, 20d
The intake air guided to b, 18c, and 18d is arranged to revolve around each of the above-mentioned axes. At this time, each main intake port 20a, 20b, 20c, 20d
is connected to each combustion chamber 18a, 18b, 1 through the same port.
The intake air guided to 8c and 18d is formed to generate a strong swirling flow, although the amount of air is small, in order to be suitable for generating high torque in the low speed operating range of the engine. On the other hand, each sub-intake port, 22a, 22b, 22
c and 22d each have one end connected to the cylinder head 12.
Each of the combustion chambers 1 is opened on the other side, and the other end is arranged so that the center of the passage is located on the side of the other side from the plane.
It opens at 8a, 18b, 18c, and 18d,
The port center line near the other end opening of each of the intake ports is oriented in a direction that does not intersect with or parallel to the cylinder axis of the corresponding combustion chamber, and each of the auxiliary intake ports 22a, 22b, 22c, 22
From d, each combustion chamber 18a, 18b, 18c, 18d
The intake air guided through the main intake air signals 20a, 20b, 20c, and 20d revolves around the respective axes in the same direction as the intake air guided through the main intake air signals 20a, 20b, 20c, and 20d. At this time, each sub-intake port 22a, 22b,
22c and 22d are connected to each combustion chamber 18 through the same port.
The intake air introduced into the air intakes a, 18b, 18c, and 18d is formed to have a relatively weak swirling flow but a large flow rate in order to be compatible with the generation of high torque in the high-speed operating range of the engine.

In addition, each combustion chamber 18a, 18b, 18c, 18d
, each main intake port 20a, 20b, 20c,
Exhaust ports 28a, 28b, 28c, and 28d extend substantially parallel to the main intake port from the side surface of the cylinder head 12, which has an opening at one end 20d, and are provided with exhaust valves 30a and 30d, respectively.
0b, 30c, and 30d are interposed.

Furthermore, each combustion chamber 18a, 18b, 18c, 18
d has openings 32a, 32b for arranging a spark plug,
32c, 32d are open, and when each spark plug 34a, 34b, 34c, 34d is disposed in each opening, each of the main intake ports 20a, 20b, 2
At least a portion of the intake air guided to each combustion chamber via 0c and 20d passes through the spark gap portion of each spark plug.

Each main intake valve 24a, 24b, 24c, 24d is connected to each main intake valve valve mechanism 36a, 36b, 36c, 3
6d, each sub-intake valve 26a,
26b, 26c, 26d are each auxiliary intake valve valve mechanism 3
8a, 38b, 38c, 38d, each exhaust valve 30a, 30b, 30c, 30d
are each exhaust valve valve mechanism 40a, 40b, 40c, 4
It is designed to be opened and closed by 0d.
Each main intake valve valve mechanism 36a, 36b, 36c, 3
6d indicates each main intake cam 4 provided on the camshaft 42.
4a, 44b, 44c, 44d and the first rocker shaft 46 to control the lift of each main intake cam.
Locker arms 48a, 48b, 48 transmitted to d
c, 48d, among which the rocker arms 48a, 48 of the main intake valve mechanism 36a, 36d
A valve operation stop mechanism is formed in b. Each sub-intake valve valve mechanism 38a, 38b, 38c, 38d is provided with sub-intake cams 50a, 50 provided on the camshaft 42.
b, 50c, 50d and rocker arms 52a, 52b, 52c, 52d that are swingably supported by the second rocker shaft 51 and transmit the lift of each of the sub-intake cams to the sub-intake valves 26a, 26b, 26c, 26d.
A valve operation stop mechanism is formed in the rocker arms 52a, 52b, 52c, and 52d of each sub-intake valve mechanism. Each exhaust valve valve mechanism 40
a, 40b, 40c, 40d are exhaust cams 54a, 54b, 54c, 54 provided on the camshaft 42
d and the first rocker shaft 46 to adjust the lift height of each exhaust cam to each exhaust valve 30a, 3.
Locker arm 56 transmitting to 0, 30c, 30d
a, 56b, 56c, and 56d, among which a valve operation stop mechanism is formed in the rocker arms 56a, 56d of the exhaust valve operating mechanisms 40a, 40d. By the way, each of the above-mentioned main intake valve operating mechanisms 36
a, 36b, 36c, 36d are each main intake valve 24
a, 24b, 24c, and 24d are opened and closed in such a way as to reduce the valve lift and shorten the valve opening period so as to be suitable for low-speed operation, and to reduce the overlap with the valve opening period of each exhaust valve 30a, 30b, 30c, and 30d; On the other hand, each sub-intake valve mechanism 38a, 38b,
38c, 38d are the respective sub-intake valves 26a, 26b, 2
6c, 26d, the valve lift is large, the valve opening period is long, and each exhaust valve 30 is made suitable for high-speed operation.
The valves are opened and closed so as to increase the overlap with the valve opening periods of valves a, 30b, 30c, and 30d.

Each rocker arm 48a, 48d, 56a, 56
The valve operation stop mechanism formed in d will be explained with reference to FIGS. 6 to 9, taking the rocker arm 48a as an example. An oil passage 62 extending in the direction shown in FIG.
A cylinder 68 is attached to the end of the other arm 66 extending to the right in the figure. Also, Rotsuka arm 48
A shows a cylinder part 78 bored in the rocker arm and a piston 80 sliding inside the cylinder part.
A hydraulic actuator 82 is provided.

The cylinder portion 78 is connected to the oil passage 62 through an oil passage 84 formed in the rocker arm 48a and a radial supply oil passage 86 formed in the first rocker shaft 46.
The locking arm 48a is always in communication with the locking arm 48a regardless of its swinging motion.

The cylinder 68 has a cylindrical plunger 88 with a bottom.
is slidably fitted inside the plunger, and the sixth plunger is moved by a spring 90 installed inside the plunger.
It is pressed downward in the figure, and the bottom surface portion of its lower end is in contact with the valve shaft end of the main intake valve 24a. Two elongated holes 92 are provided in the cylindrical wall of the cylinder 68 so as to face each other and are located directly above the upper end of the plunger 88 when the plunger 88 is at the lowest position relative to the cylinder 68 (the position shown in the figure). As shown in FIG. 7, a stopper 94, which is a movable member having fork-shaped legs, is inserted into the elongated hole. An arcuate space 96, which is slightly larger than the outer diameter of the plunger 88, is formed at the base between the two legs of the stopper 94, and the distance between the inner edges of the two legs is this distance. Arc-shaped space 9
It is set to be approximately equal to the inner diameter of the plunger 88 on the right side of the plunger 6 . A screw is formed on the upper outer surface of the cylinder 68, and a double nut 95 is screwed onto the screw to guide the upper surface of the stopper 94 in order to smoothly slide the cylinder 68.
A presser spring 9 is provided between the stopper 94 and the locking arm 48a to prevent vertical vibration of the stopper.
7 is interposed. A long hole 98 is formed at the left end of the stopper 94, and the piston 80 is inserted into this long hole.
A pin 104 of a connecting member 102 is fixed to the right end of the rod 100 attached to the piston, and the stopper and the piston are connected via this connecting member 102 and the rod 100.
When the pin 104 is installed, a gap S is created in the elongated hole 98 in the left-right direction, which is the sliding direction of the piston 80, so the stopper 94 is connected to the piston 80 in the left-right direction relative to the piston 80 by the gap S. has been done. The piston 80 is biased leftward by the spring 105, and is displaced to the leftmost position within the cylinder section 78 when no hydraulic pressure is acting within the cylinder section 78. A notch 106 is provided above the intermediate portion of the cylindrical wall portion of the piston 80, and this notch allows the piston 80 to be positioned at the rightmost position within the cylinder portion by hydraulic pressure supplied to the cylinder portion 78 via the oil passage 84. The timing plate 108 is adapted to engage the timing plate 108 from time to time. timing plate 108
As shown in FIG. 8, the piston 80 is rotatably supported by a shaft 110 attached to the rocker arm 48a, and slides in a groove 112 provided above the outside of the cylinder portion 78. It is configured to be able to engage with the right end in FIG. 6 and the notch 106. The timing plate 108 is biased in the piston engaging direction (clockwise in FIG. 8) by a spring 114, and is also configured to be pressed from below by a timing cam follower 116 having a substantially cylindrical shape. . The timing cam follower 116 is configured to follow the swinging of the rocker arm 48a by a timing cam 118 formed by scraping a part of the outer peripheral surface of the first rocker shaft 46 along its circumferential direction. The first rocker shaft 46 is configured so that it can be largely slid outward in the radial direction of the first rocker shaft 46 when the rocker arm is at or near its maximum swing (the lift of the cam 44a is at or near its maximum). In response to this radially outward sliding, the timing plate 108 is rotated counterclockwise in FIG.
The engagement with the piston 80 is disengaged when the rocking motion is at or near the maximum.

The hydraulic pressure supplied to and discharged from the actuator 82 through the supply oil passage 86 and the oil passage 84 is the hydraulic pressure interposed in a first oil supply passage, which will be described later, and which is connected to the oil passage 62 at the end of the rocker shaft 46. First hydraulic switching valve 136 (OCV-1) which is supply control means
The supply/discharge is controlled by the switching operation.

Regarding the operation of the valve actuation stop mechanism of the rocker arm 48a having the above configuration, FIGS. 9a to 9d
Explain with reference to. In addition, in FIGS. 9a to 9d, the structure is shown more schematically than in FIGS. 6 to 8 so that the principle of operation can be more clearly understood.

When hydraulic pressure is not supplied to the actuator 82 due to the switching operation of the first hydraulic pressure switching valve 136, the piston 80 is positioned at the leftmost position due to the pressing force of the spring 105, as shown in FIG. The upper end of 88 engages with the stopper 94, thereby stopping the sliding of the plunger within the cylinder 68, making the main intake valve 24a operable, and the cam lift of the main intake cam 44a causes the rocker arm 48a to swing. When moved, plunger 88 causes main intake valve 24a to open. In this state, the timing plate 108 and the piston 8
The right end portion of 0 can be engaged with the right end portion of 0. Next, when hydraulic pressure is supplied to the actuator 82 from this state, the piston 80 is pushed to the right by the hydraulic pressure, but as shown in FIG. 9a, the main intake cam 44
During the period a when the cam lift is not occurring, the timing plate 108 continues to be able to engage with the right end of the piston 80, so the piston 80 does not slide to the right. Next, when the cam lift occurs and reaches the maximum value or near it, the rocker arm 48a swings as shown in FIG. 9b, and the timing cam follower 116 moves the timing cam
18, the timing plate 108 moves upward (rotates counterclockwise in FIG. 8) and engages with the right end of the piston 80. is removed, and the piston slides to the right due to hydraulic pressure. However, in this state, the cam lift occurs as described above, the rocker arm 48a swings, and the plunger 88 moves to the stopper 94.
Since the stopper 94 is in pressure contact with the stopper, the stopper 94 cannot slide due to the frictional force caused by this pressure contact, and the piston 80 slides by the size of the gap S provided at the connection part with the stopper, and the right end and timing This is a position where the plate 108 is not engaged. Thereafter, when the cam lift is completed, the stopper 94 is released from the pressure contact with the plunger 88 and becomes slidable, as shown in FIG. Hole 9
2 to the right, and an arcuate space 96 is located at the upper end of the plunger 88. In this state, the plunger 88 becomes slidable within the cylinder 68, and the main intake valve 24a stops operating and maintains the closed state. At this time, when the cam lift of the main intake cam 44a is not occurring, the timing plate 108 is moved against the piston. It will engage with the notch 106 of 80.

Next, from the state in which the valve operation is stopped as shown in FIG. Although it is pressed, the piston 80 cannot slide to the left because the timing plate 108 is engaged with the notch 106 in the piston during a period when cam lift is not occurring. When the cam lift occurs and reaches the maximum value or near it, the timing plate 108 disengages from the notch 106 of the piston, as shown in FIG. Moving. However, in this state, the plunger 88 slides upward in the cylinder 68 due to the swinging of the locker arm 48a and cools the elongated hole 92 before the engagement is disengaged, so the stopper 94 cannot slide.
The piston 80 slides by the size of the gap S provided in the connecting portion with the stopper, and reaches a position where the notch 106 and the timing plate 108 do not engage. After that, when the cam lift is completed, the upper end of the plunger 88 is located below the elongated hole 92 and the stopper 94 becomes slidable, so that the spring 10
The piston 80 and the stopper 94 move to the left by the biasing force of the plunger 8.
8, that is, the plunger is in a state in which sliding within the cylinder 68 is stopped. As a result, when the main intake cam 44a next causes a cam lift and the rocker arm 48a swings, the plunger 88 opens the main intake valve 24a.

The valve operation stop mechanism having the above-described structure includes not only the locker arm 48a but also the locker arms 48d, 56a, and 48d, which are swingably supported on the first locker shaft 46.
56d, and supply and discharge of hydraulic pressure to actuators (not shown) of these rocker arms is performed by the first hydraulic pressure switching valve, as in the case of the actuator 82 of the rocker arm 48a.
In addition, each sub-intake valve 26a, 26b, 26c, 26d
Each rocker arm 52a, 52b, 52c, 5 for
A valve operation stop mechanism similar to the locking arm 48a is also formed on the locking arm 2d, and the locking arm 52a, 52b,
Like the first rocker shaft 46, an oil passage 59 extending in the axial direction is formed in the second rocker shaft 51 that swingably supports the rocker arms 52c and 52d, and an oil passage 59 is formed in the actuator (not shown) of each of the rocker arms. Hydraulic pressure is supplied and discharged from the oil passage 59, and this oil pressure supply and discharge control is performed by a second oil pressure supply control means that is interposed in a second oil supply passage that is communicated with the oil passage 59 and will be described later. This is done by switching the hydraulic pressure switching valve 137 (OCV-2). However, the valve operation stop mechanism formed on the rocker arms 52a, 52b, 52c, and 52d for each sub-intake valve enables the valve to operate when hydraulic pressure is supplied to the actuator, and stops the valve operation when the hydraulic pressure is discharged. It is something to do. This valve operation stop mechanism will be explained using the rocker arm 52a as an example with reference to FIGS. 10 and 11. In FIGS. 10 and 11, the same members or members having substantially the same functions as the valve actuation stop mechanism explained using FIGS. 6 to 9 are designated with the same reference numerals, and detailed explanations are given. The explanation will be omitted. The oil passage 59 communicates with the cylinder portion 78 of the actuator 82 via a radial supply oil passage 120 formed in the second rocker shaft 51 and an oil passage 122 formed in the rocker arm 52a. The stopper 94 has an arcuate space 96 that is slightly larger than the outer diameter of the plunger 88 near its left end, that is, near the tip of the leg inserted into the elongated hole 92. The distance between the inner edges is set to be approximately equal to the inner diameter of the plunger 88. Further, a hook-shaped portion having a substantially C-shape is formed at the right end of the stopper 94, and this hook-shaped portion connects the connecting member 102 attached to the rod 100 to create a gap S along the sliding direction of the piston 80. It is surrounded by a stopper 94 and a rod 100.
(piston 80) are connected to each other with a gap S therebetween. The connecting member 102 is formed into a cylindrical shape with a square cross section perpendicular to the sliding direction of the piston 80.

The valve actuation stop mechanism formed in the rocker arm 52a allows the arcuate space 96 of the stopper 94 to be located at the upper end of the plunger 88 when hydraulic pressure is not being supplied to the actuator 82 due to the operating state of the second hydraulic switching valve 137. This allows the plunger to slide within the cylinder 68, and the sub-intake valve 2
6a is stopped and hydraulic pressure is supplied to the actuator 82, the upper end of the plunger 88 and the leg of the stopper 94 can come into contact, the sliding of the plunger within the cylinder 68 is stopped, and the sub-intake valve 26a is activated.

As shown in FIG. 12, the first oil supply passage 132 whose one end communicates with the oil passage 62 and the second oil supply passage 133 whose one end communicates with the oil passage 59 have their respective other ends. This merging oil supply passage 134 is connected to the oil pump 1 of the main passage 130 that supplies lubricating oil to each lubricating system (not shown) of the engine.
It communicates with the downstream side of the intervening position of No. 35. The first oil supply passage 132 and the second oil supply passage 133 are provided with the aforementioned first hydraulic switching valve 136 and second hydraulic switching valve 137, respectively, and the merging oil supply passage 134 is provided with the aforementioned oil pump. 1st from the 135 side,
A first check valve 13 that allows oil to flow only from the second oil supply path 132, 133 side, that is, from the upstream side to the downstream side.
8. Hydraulic switching valves 136 in which a pressure booster pump 139, a second check valve 140 that allows oil to flow only from the upstream side to the downstream side, and a pressure accumulator 141 are sequentially arranged from the upstream side to the downstream side. , 137 are fitted in the housings 142, 143 and slide within the housings in accordance with the energization/de-energization of the solenoids 144, 145. hydraulic port 14
8, 149, atmospheric ports 150, 151, and supply ports 152, 153, and hydraulic ports 148, 149 are connected to the combined oil supply path 134, respectively.
The atmospheric ports 150 and 151 are each opened to the atmosphere, that is, they are connected to an oil pan (not shown) of the engine, and the supply ports 152 and 153 are connected to oil passages 62 and 59, respectively. solenoid 1
44 and 145 are controlled to be energized or de-energized by a computer C, which is a control means that detects the operating state of the engine and outputs an output according to the detection result. By the way, in the hydraulic switching valve 136 (OCV-1),
When the solenoid 144 is energized, the valve body 146 closes the atmospheric port 150, allowing communication between the hydraulic port 148 and the supply port 152, and when the solenoid 144 is de-energized, the valve body 146 closes the atmospheric port 150.
closes hydraulic port 148 and atmospheric port 150
On the other hand, in the hydraulic switching valve 137 (OCV-2), when the solenoid 45 is energized, the valve body 147 closes the hydraulic port 149 and connects the atmospheric port to the supply port 152. 151 and the supply port 153, and when the solenoid 145 is de-energized, the valve body 147 closes the atmospheric port 151 and allows the hydraulic port 149 and the supply port 153 to communicate. The pressure booster pump 139 has a piston 154 inside and a spring 155 that urges the piston downward in FIG.
The rod 157 slides back and forth within the cylinder of the pump 139 due to the vertical movement of the rod 157 caused by the rotation of the eccentric cam 156 driven by the engine, thereby increasing the oil pressure from the oil pump 135.
The pressure accumulating device 141 includes a main body 158, a pressure accumulating chamber 159 formed within the main body, a piston 160 disposed within the pressure accumulating chamber, and urging the piston in a direction that reduces the volume of the pressure accumulating chamber 159, that is, to the right in FIG. It has a spring 161 that does. The maximum effective volume V ₀ of the pressure accumulation chamber 159 is determined by the sum of the working volumes of the actuators provided in the rocker arms 48a, 48d, 56a, and 56d provided with the valve action stopping mechanism, and the sum of the working volumes of the actuators provided in the rocker arm 52 provided with the valve action stopping mechanism.
It is set to be larger than the sum of the working volumes of the actuators provided in a, 52b, 52c, and 52d, for example, the working volume of each actuator is set to 2 c.c.
In this case, it is preferable to set V ₀ to about 10 c.c. In addition, the biasing force of the spring 161 is applied to the valve body 14.
6, 147 are hydraulic ports 148, 149 respectively
is sufficiently compressed by the discharge pressure of the booster pump 139 when the valve body is closed to ensure a volume _V0 , and one of the valve bodies 146 and 147 connects the corresponding hydraulic port to the corresponding supply. When communicating with the port, the lubricating oil in the pressure accumulation chamber 159 is immediately supplied to the cylinder portion of each actuator. Further, the oil passage 62 is communicated with a first bypass passage 162, and the oil passage 59 is communicated with a second bypass passage 163, these bypass passages merge at their other ends, and this merging bypass passage 164 The oil passage 165 supplies lubricating oil to the journal portion of the camshaft 42 (not shown) and the throttle 166 communicates with the upstream side of the intervening position of the check valve 138 of the merging oil supply passage 134. In the bypass passages 162 and 163, there are provided a third check valve 167 and a fourth check valve 1 that allow oil to flow only from the combined oil supply passage 134 to the oil passages 62 and 59, respectively.
68 are arranged. Merging bypass passage 164
A hydraulic pressure lower than the discharge pressure of the oil pump 135 is supplied through a throttle 166, and the first and second hydraulic pressure switching valves 136, 137 are connected to the supply port 15.
2,153 are in communication with the atmospheric ports 150,151, the oil pressure is applied to the first and second check valves 16.
Bypass passage 162,16 through 7,168
3. Oil passages 62, 59 and oil supply passages 132, 13
3 to the actuator 8 of each rocker arm.
It is adapted to act on the piston 80 of No. 2.
Note that this oil pressure is applied to the throttle 166 and the check valve 16.
7,168, the oil pressure is set to a low level that does not operate the piston of the actuator.

Next, the intake and exhaust system of the engine connected to each of the above-mentioned intake and exhaust ports will be explained with reference to FIGS. 1 and 2. Each main intake port 20a, 20b,
20c and 20d are connected to the main throttle valve 204 and the fuel injection device 2 on the upstream side thereof through the intake manifold 202 from an opening on one side of each cylinder head.
06 is interposed therein, and this main intake passage communicates with the outside air via a cylindrical first air cleaner 210. Therefore, air-fuel mixture is supplied to each fuel chamber from each main intake port 20a, 20b, 20c, 20d. In this main intake passage 208, an air flow sensor (not shown) is disposed inside the first air cleaner 210.
The amount of air inhaled through the device is now measured. The detection result of the air flow sensor is input to the computer C and used as data when calculating the fuel injection amount of the fuel injection device 206.

1 and 2, each sub-intake port 22a, 22b, 22c, 22d is connected to each sub-intake pipe 24 at the opening on the other side of the cylinder head.
0a, 240b, 240c, and 240d, and the other ends of each sub-intake pipe open into the surge tank 242, respectively. The surge tank 242 communicates with a sub-intake passage 246 in which a sub-throttle valve 244 is interposed, and is further opened to the atmosphere via a second air cleaner 248. The sub-throttle valve 244 is connected to the main throttle valve 204 via an interlocking cable 252, and both the main and sub-throttle valves 204, 244 are rotated according to the amount of depression of an accelerator pedal (not shown), which is connected via the throttle wire 254. It will be done. However, the main throttle valve 204 rotates from the fully closed position (idling position) to the fully open position in response to the accelerator pedal moving from the idling position to the maximum depression position, but the auxiliary throttle valve 244 rotates from the fully closed position (idling position) to the fully open position.
While the accelerator pedal moves from the idling position to the set intermediate depressed position, that is, while the main throttle valve 204 rotates from the fully closed position to the set half-open position, the accelerator pedal is in the fully closed position. The main throttle valve 204 rotates from the fully closed position to the fully open position in response to movement from the intermediate depressed position to the maximum depressed position (that is, the main throttle valve 204 rotates from the half-open position to the fully open position). Furthermore, each exhaust port 28a, 28b, 28
C and 28d communicate with an exhaust manifold 256 through an opening on one side of the cylinder head, and communicate with the outside air via an exhaust pipe 258. exhaust manifold 256
is formed in partial contact with the intake manifold 202, so that the intake air guided to the intake manifold via the main intake passage 208 is heated by the exhaust gas.

By the way, the computer C, which is an actuator control means that controls the fuel injection amount and controls the energization and de-excitation of the solenoids 144 and 145 of the above-mentioned hydraulic switching valves 136 and 137, has the following functions.
Water temperature sensor 30 that detects the temperature of engine cooling water
1. A pressure sensor 302 that detects the intake pressure downstream of the main throttle valve 204 in the engine intake passage 208, an opening sensor 303 that detects the opening of the main throttle valve 204, and a rotational speed that detects the engine rotational speed. A sensor 304, a transmission switch 30 that detects whether the transmission is in a low gear position (for example, a low gear position) or a reverse position
6 and the cranking switch 307 that detects the cranking state of the engine (that is, the state in which the starter motor is operating) are input, and the computer C performs the following based on these input signals. The hydraulic switching valves 136 and 137 are controlled so that the three valve operating states shown in FIG. By the way, the above three valve operating states are: X...main intake valves 24b, 24c, exhaust valve 30b,
Only 30c operates Y...All main intake valves 24a, 24b, 24c,
24d and all exhaust valves 30a, 30b, 3
0c, 30d are activated (all auxiliary intake valves are not activated) Z...All main intake valves 24a, 24b, 24c,
24d All sub-intake valves 26a, 26b, 26
c, 26d and all exhaust valves 30a, 30
b, 30c, and 30d are in operation. Here, the mode in which the computer C sets the valve operating state in response to each input signal will be explained using the flowchart of FIG. 13. The program shown in FIG. 13 is executed using an interrupt signal at each set time as a trigger, and first, at A-1, the detection results of the above-mentioned sensors 301 to 307 are read, and then at A-2, the cranking switch is activated. Detection results of 307 and rotation speed sensor 30
Based on the detection result of step 4, it is determined whether or not it is time to start the engine. That is, in A-2, it is determined that it is time to start if the cranking switch 307 is on (that is, the starter motor is activated) or if the engine rotation speed is below the first set rotation speed (for example, 300 rpm). Reaching A-11, A-11
Solenoid 144 of first hydraulic switching valve 136
A control signal is output from the computer C so that the solenoid 145 of the second hydraulic switching valve 137 is de-energized and the solenoid 145 of the second hydraulic switching valve 137 is energized, instructing execution of the above-mentioned valve operating state Y. Then, at A-14, the computer C
1 is input to address K of the RAM, and the program is terminated. If it is determined at A-2 that the cranking switch 307 is off and the engine speed is equal to or higher than the first set rotation speed, the process proceeds to A-3. In A-3, rotation speed sensor 3
04, it is determined whether the engine is being operated at high speed based on the detection results of the pressure sensor 302 and the opening sensor 303. That is, in A-3, it is determined based on the detection result of either the pressure sensor 302 or the opening sensor 303 that the engine is being operated at a low load that is below the first set load level, and that the rotational speed is Based on the detection result of the sensor 304, the engine speed changes to the second set speed (e.g.
2500 rpm) or higher, or it is determined based on one of the detection results described above that the engine is being operated at a high load equal to or higher than the first set load level, and the pressure sensor 30
2. Based on the detection result of the other of the opening sensors 303 and the detection result of the rotation speed sensor 304, the engine rotation speed is set according to the load level (this set rotation speed is the second rotation speed mentioned above). If it is determined that the engine speed is lower than the set rotation speed (which is set to be lower than the set rotation speed and gradually decreases as the load level rises), it is determined that the engine is being operated at high speed, and A-13 is reached. 13, a control signal is output from the computer C so that the solenoid 144 of the first hydraulic switching valve 136 is de-energized and the solenoid 145 of the second hydraulic switching valve 137 is de-energized, and the above-mentioned valve operating state Z is executed. instructed,
Next, at A-16, 2 is input to the above-mentioned address K, and the program is terminated.

In addition, if it is determined in A-3 that the engine is not being operated at high speed, that is, the engine speed is below the second rotation speed during low load operation, or the engine speed is lower than the second rotation speed during high load operation. If it is determined that the rotation speed is below the set rotation speed, the process proceeds to A-4. In A-4, water temperature sensor 301
Based on the detection result, it is determined whether or not the engine has finished warming up. In other words, in A-4, if the temperature of the engine cooling water is below the warm-up end temperature setting (e.g. 70°C), it is assumed that warm-up has not been completed.
11, execution of the above-mentioned valve operation state Y is instructed, and if the temperature of the cooling water of the other engine exceeds the warm-up end set temperature, warm-up is considered complete and A-5.
leading to. At A-5, it is determined whether the engine temperature (particularly the lubricating oil temperature) has become high based on the detection result of the water temperature sensor 301. That is A-5
In A-6, the engine temperature is determined to be high when the temperature of the engine cooling water is higher than the first set temperature (for example, 110°C). It is determined whether or not the engine rotation speed is in the low rotation speed region, and the engine rotation speed is set to a third set rotation speed (for example, 1000 rpm).
In the following cases, execution of the above-mentioned valve operation state Y is instructed at A-11. That is,
In A-5 and A-6, a hydraulic type valve actuation stop mechanism is formed in each rocker arm based on the viscosity state of the lubricating oil detected from the temperature state and rotation speed state of the engine and the discharge pressure of the pressure booster pump 139. This means that it is determined whether the pressure state of the lubricating oil supplied to the actuator is extremely low, and if it is determined that the pressure state is extremely low, A-11 It is starting to reach this point. In addition, if it is determined in A-5 that the temperature of the engine cooling water is less than the first set temperature, and if it is determined in A-6 that the engine speed is higher than the third set speed, It is determined that the pressure state of the lubricating oil supplied to the hydraulic actuator is not extremely low, and the process proceeds to A-7. Pressure sensor 30 in A-7
Based on the detection result of either the opening sensor 2 or the opening sensor 303 and the detection result of the transmission switch 306, it is determined whether the engine is in a partial cylinder operating state. That is, in A-7, the engine is operating at a low load lower than the second set load level according to the detection result of the pressure sensor 302 or the opening sensor 303, and the transmission switch 3
Based on the detection result of step 06, when the gear shift position of the transmission at that time is not in the low gear position or the reverse position, it is determined that the engine operating state is in the partial cylinder operating state, leading to A-8, and the pressure sensor 302 or When the engine is being operated at a high load higher than the second set load level according to the detection result of the opening sensor 303, or when the gear position of the transmission is in the low gear position or the reverse position according to the detection result of the transmission switch 306. In this case, it is determined that the engine operating state is not in the partial cylinder operating state, and the process reaches A-11, in which execution of the above-mentioned valve operating state Y is instructed. A
-8, A in the previous program execution
It is determined whether the valve operating state indicated by -11, A-12 or A-13 is X (that is, partial cylinder operation). That is, at A-8, it is determined whether the value input to address K at A-14, A-15, or A-16 during the previous program execution is 0, which was input at A-15. If the address K is 0, it reaches A-12. In A-12, the first hydraulic switching valve 13
6 solenoid 144 is energized, the 1st hydraulic switching valve 1
A control signal is output from the computer C so that the solenoid 145 of No. 37 is energized, instructing execution of the above-mentioned valve operating state X, and then 0 is input to the address K of the RAM at A-15, and the program is terminated. . Also, in A-8, address K
If it is determined that the value input to is not 0, that is, if partial cylinder operation has not been instructed by the previous program execution (valve operation state Y has been instructed), the process proceeds to A-9. At A-9, it is determined whether the engine temperature (particularly the lubricating oil temperature) is relatively high based on the detection result of the water temperature sensor 301. In other words, in A-9, when the temperature of the engine cooling water is higher than the second set temperature (for example, 105°C), the engine temperature is considered to be relatively high and reaches A-10, and in A-10, the rotation Based on the detection result of the speed sensor 304, it is determined whether the engine rotation speed is in a low rotation speed region, and the engine rotation speed is set to a fourth set rotation speed (for example, 1000 rpm).
In the following cases, execution of the above-mentioned valve operation state Y is instructed at A-11. That is, A
-9 and A-10, the hydraulic system of the valve operation stop mechanism formed in each rocker arm is based on the viscosity state of the lubricating oil and the discharge pressure of the booster pump 139, which are detected from the temperature state and rotation speed state of the engine. This means that it is determined whether the pressure state of the lubricating oil supplied to the actuator is relatively low, and if it is determined that the pressure state is relatively low, A -11. In addition, if it is determined in A-9 that the temperature of the engine cooling water is less than the second set temperature, and if it is determined in A-10 that the engine speed exceeds the set speed in 4, the above It is determined that the pressure of the lubricating oil supplied to the hydraulic actuator is not relatively low, and A
-12, execution of the above-mentioned valve operating state X is instructed.

According to the above configuration, in FIG. 13 A-2
NO, NO in A-3, YES in A-4
In the operating state where the determination is made, when the oil pressure of the lubricating oil supplied to the hydraulic actuator of the valve operation stop mechanism is relatively high, the determination of A-7 is made.
When NO, the solenoid 144 of the first hydraulic switching valve 136 is de-energized, so that no hydraulic pressure is applied to each cylinder portion 78 of the rocker arms 48a, 48d, 56a, 56d, and each stopper 94 is located at the engagement position (valve operating position) with respect to the upper end of the plunger 88. As a result, the valve operating state Y described above is executed. From this state A
-7 is switched to YES, solenoid 1
44 is energized, thereby each cylinder portion 78
Hydraulic pressure is applied to each stopper 94, and each stopper 94 moves from the valve operating position to a non-engaging position with respect to the upper end of the plunger 88 (valve non-actuating position), and maintains this valve non-actuating position as long as the determination in A-7 is YES. . As a result, the valve operating state X described above is executed. Next, when the determination of A-7 is switched to NO again from this state, the solenoid 144 is de-energized, thereby eliminating the hydraulic pressure acting on each cylinder part 78, and each stopper 94 deactivates the valve. The valve moves from the operating position to the valve operating position, and the valve operating state switches from X to Y.

Next, as a result of the determination in A-7, the oil pressure of the lubricating oil supplied to the hydraulic actuator switches from a relatively high state to a relatively low state while the valve operating state Y is being executed, and after that, A- If the determination result in step 7 changes from NO to YES, A-
8 is NO, A-9, and A-10 are YES, so at this time, no hydraulic pressure is applied to each cylinder part 78, and therefore the valve operating state does not change from Y to X. continues.

Furthermore, as a result of the determination in A-7, when the oil pressure of the lubricating oil supplied to the hydraulic actuator switches from a relatively high state to a relatively low state while the valve operating state X is being executed, this switching Immediately after, the determination of YES continues at A-8, so the oil pressure continues to act on the cylinder portion 78, thereby continuing the valve operating state X.
Next, when the determination of A-7 switches from YES to NO from this state (the state where the oil pressure is relatively low), the oil pressure that was acting on each cylinder part 78 is removed, and the valve operating state is switched from X to Y. Change. If the determination of A-7 switches from NO to YES again from this state, NO for A-8 and YES for A-9 and A-10.
Since this determination is made, no hydraulic pressure is applied to each cylinder portion 78 at this time, and the valve operating state Y continues.

Furthermore, if the oil pressure of the lubricating oil supplied to the hydraulic actuator becomes extremely low and a state is reached where a YES determination is made in each of FIG. 13 A-5 and A-6, the determination result in A-7 will be ignored. Therefore, the action of hydraulic pressure on each cylinder portion 78 is stopped, and the valve operating state Y is executed.

Therefore, when the oil pressure of the lubricating oil supplied to the hydraulic actuator is relatively low and the driving force of the piston 80 due to this oil pressure is not sufficiently large compared to the biasing force of the spring 105, the determination in FIG. As a result, even if the operating state is such that the stopper 94 should be switched from the valve operating position to the valve non-operating position, oil is not supplied to the cylinder portion 78 and the stopper 94 does not move, so that the stopper 94 and the plunger 88 are may not engage in an incomplete position, and abnormally high stress may occur in the engaging portions of the stopper 94 and the plunger 88, which may lead to damage.
This has the effect of preventing noise from being generated.

In addition, during operation other than starting the engine, the oil pressure of the lubricating oil supplied to the hydraulic actuator is extremely low, and this oil pressure causes the spring 105 to
If it becomes difficult to hold the stopper 94 in the valve non-operating position against the urging force of
4 quickly moves to the valve operating position, the stopper 94 and plunger 88 do not engage in an incomplete position, and the same effect as described above is achieved.

In the above embodiment, the water temperature sensor 301 and the rotation speed sensor 304 were used to detect the oil pressure of the lubricating oil supplied to the hydraulic actuator, but when detecting the oil pressure, the oil temperature of the lubricating oil was detected. An oil temperature sensor may be provided, and the oil pressure may be detected from the detection result of this oil temperature sensor and the detection result of the rotation speed sensor 304,
In addition, from the oil pump 135 to the pressure booster pump 139
A hydraulic pressure sensor is provided to detect the oil pressure upstream of the first check valve 138, and the pressure is supplied to the hydraulic actuator based on the detection result of this hydraulic pressure sensor and the detection result of the water temperature sensor 301 or the oil temperature sensor. It may be configured to detect the oil pressure of the lubricating oil;
Furthermore, a position sensor may be provided to detect the position of the piston 160 of the pressure accumulator 141, and the hydraulic pressure of the lubricating oil supplied to the hydraulic actuator may be detected from the detection result of the position sensor.

Further, in the above embodiment, as shown in Figure 6 of British Patent No. 2075118A, a stopper that can be removed from the system is provided between the rocker arm body and the plunger that constitute the transmission member of the valve train, and the stopper is hydraulically operated. Although the poppet valve is switched between actuation and non-operation by being driven by an actuator, the present invention also applies to a locker arm, etc. of a valve train as shown in Fig. 7 or Fig. 8 of JP-A No. 54-153919. Needless to say, the present invention is also applicable to a poppet valve which is switched between actuation and non-operation by moving the fulcrum position of the hydraulic actuator.

In the above embodiment, only the one that stops the operation of the valve was explained, but the present invention has the same operation and effect as the above embodiment as long as it suppresses the operation of the valve so as to partially stop it. be.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing one embodiment of an automobile engine equipped with a valve operation stop mechanism according to the present invention, and FIG.
The figure is a sectional view of the engine shown in Fig. 1, Fig. 3 is a sectional view of the combustion chambers 18b and 18c of Fig. 1, Fig. 4 is a sectional view of the combustion chambers 18a and 18d of Fig. 1, and Fig. 5 is a sectional view of the engine shown in Fig. 1. is another sectional view of the combustion chambers 18b and 18c in FIG. 1, FIG. 6 is a partial sectional view of the rocker arm 48a, FIG. 7 is a sectional view taken along the line - in FIG. 6, and FIG. FIG. 9 is an explanatory diagram of the operation of the locker arm 52a, FIG. 10 is a partial cross-sectional view of the locker arm 52a, and FIG.
12 is a schematic explanatory diagram showing a hydraulic pressure supply system for supplying hydraulic pressure to the rocker arm, and FIG. 13 is a flowchart of the operation according to the above embodiment. 10...Engine, 18a, 18b, 18c,
18d... Combustion chamber, 24a, 24b, 24c, 2
4d...Main intake valve, 26a, 26b, 26c, 2
6d...Sub-intake valve, 30a, 30b, 30c, 3
0d... Exhaust valve, 46, 51... Rotsuka axis, 48
a, 48b, 48c, 48d, 52a, 52b,
52c, 52d, 56a, 56b, 56c, 56
d...Rotsuka arm, 59, 62...Oil path, 82
... Actuator, 88 ... Plunger, 94
... Stoppa, 105 ... Spring, 132,
133... Oil supply path, 134... Merging oil supply path,
135... Oil pump, 136, 137... Hydraulic switching valve, 139... Pressure booster pump, 141... Pressure accumulator, 162, 163... Bypass passage, 16
4... Merging bypass passage, 166... Throttle, 16
7,168...Check valve, 301...Water temperature sensor,
304...Rotation speed sensor.

Claims (1)

[Claims] 1. In a valve operation suppression mechanism that suppresses the operation of intake and exhaust valves of an engine according to operating conditions, between a first position where the intake and exhaust valves are operated and a second position where the operation of the intake and exhaust valves is suppressed. a movable member disposed so as to be movable; a biasing member that biases the movable member toward either the first position or the second position; and a biasing member that engages with the movable member. a hydraulic actuator that holds the movable member at the other of the first position or the second position against the biasing force of the biasing member when hydraulic pressure is supplied to the hydraulic actuator; a hydraulic pressure supply means for supplying hydraulic pressure; a hydraulic pressure supply control means for controlling the supply of hydraulic pressure to the hydraulic actuator by the hydraulic pressure supply means; a hydraulic pressure drop detection means for detecting a state of decrease in the hydraulic pressure supplied to the hydraulic actuator; When operating other than starting the engine,
and actuator control means for supplying a control signal to the oil pressure supply control means so that the oil pressure is removed from the hydraulic actuator when the oil pressure drop detection means detects a reduced state of the oil pressure. A control device for the valve operation suppression mechanism.