JPS6329097B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an engine that controls the number of operating cylinders.

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 valves and exhaust valves of some cylinders are stopped to deactivate these cylinders, and the cylinders are put into operation. An engine with a controlled number of operating cylinders has been proposed in which the intake valve and the exhaust valve are operated again in response to the above condition, thereby operating all cylinders.

If the exhaust valve is deactivated after the intake valve during one cycle of suction, compression, explosion, and exhaust, depending on the timing, the inhaled air or mixture or its combustion product gas may be exhausted. After that, the only gas remaining in the cylinder is the gas that fills the gap at the top dead center of the piston under the exhaust pipe pressure conditions. When the piston descends from this state with the intake valve and exhaust valve remaining closed, the pressure inside the cylinder becomes negative pressure, and this negative pressure causes oil to be sucked into the cylinder. Afterwards, when the cylinder resumes operation, not only does the oil burn and oil consumption increases, but also problems such as carbon sludge buildup and harmful exhaust gas components increase. Additionally, when returning from a cylinder-deactivated operating state to a normal operating state, if the exhaust valve is restarted after the intake valve, the gas trapped inside the cylinder will blow back into the cylinder during the intake stroke immediately after the cylinder is restarted. As a result, new air or air-fuel mixture is not sufficiently sucked into the cylinder, resulting in incomplete operation of the cylinder, resulting in problems such as smooth operation and an increase in harmful exhaust gas components.

The present invention has been made in order to solve the above-mentioned problems, and includes a plunger that is slidably provided on the intake valve side valve operating means and the exhaust valve side valve operating means of the engine, and a plunger that is slidably provided on both the valve operating means. an engagement position that restricts the sliding of the plunger and allows the opening and closing operations of the intake valve and the exhaust valve, and a disengagement position that allows the sliding of the plunger and stops the opening and closing operations of both the valves. a stopper that is movable during a period in which cam lift is not occurring between the engagement position and the disengagement position; and the stopper is moved from one position to the other position or vice versa between the engagement position and the disengagement position. A valve operation stop mechanism comprising an actuator and a control means that detects the phase of the cam and starts moving the stopper immediately after the lift of the cam ends, and a valve operation stop signal or a valve operation signal according to the operating state. and an engine rotational phase detection device that detects the rotational phase of an engine that can stop valve operation and return valve operation from the exhaust valve after the signal is generated from the determination device, and gives an operation command to the actuator. The present invention provides an engine that controls the number of operating cylinders.

According to the above configuration, when the determination device outputs the valve operation stop signal or the valve operation signal, the engine rotation phase detection device detects the phase of the engine rotation and stops the valve operation and returns the valve operation from the exhaust valve. An operation command is given to the actuator at the phase of the engine rotation to be obtained, and the switching operation is performed. Therefore, since the valve operation is stopped or switched to return, the exhaust valve always takes precedence over the intake valve, so that when the valve operation is returned to operation, smooth operation can be achieved and an increase in harmful components of the exhaust gas can be prevented. Further, since the inside of the cylinder does not become negative pressure when the valve operation is stopped, the problem of oil being sucked into the cylinder can be eliminated.

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

In FIG. 1, the operating cylinder number control engine according to the present invention has first, second, third and fourth cylinders 1,
It is shown as a 4 cylinder engine with 2, 3 and 4 cylinders. Each of the cylinders 1, 2, 3, and 4 communicates with an intake manifold 10 and an exhaust manifold 12, and the intake manifold 10 is provided with injectors 14, 16, 18, and 20 of a fuel injection device near the connection portion with each cylinder. These injectors are driven by output signals from an electrical control unit 22 which receives a number of signals representative of engine operating conditions.

In this embodiment, the second and third cylinders 2 and 3 are configured to be deactivated, and the operation or deactivation of the second and third cylinders is controlled by the intake valves and exhaust valves (not shown) of these cylinders. It is controlled by intake valve-side valve operation/stop mechanisms 24 and 26 and exhaust valve-side operation/stop mechanisms 28 and 30, which operate or stop the valves. Each of the valve operation/stop mechanisms 24, 26, 28, and 30 is of a hydraulic type, and operates the intake valve and exhaust valve when hydraulic pressure is supplied from a hydraulic source 32 such as an engine oil pump. . The intake valve and exhaust valve side valve operation stop mechanisms 24 and 28 of the second cylinder 2 are connected to a hydraulic pressure source 32 via a first hydraulic pressure switching device 34, and the intake valve and exhaust valve side valve operation stop mechanisms of the third cylinder 3 26 and 30 are connected to a hydraulic power source 32 via a second hydraulic switching device 36. Each hydraulic switching device 3
4 and 36 are three-way solenoid valves that communicate the valve operation stop mechanism with the hydraulic source 32 or open it to the atmosphere, and the control device 22 depending on the operating state of the engine.
Its operation is controlled by hydraulic pressure switching commands issued from the hydraulic pressure switching command. Although not shown in the drawings, the electrical control device 22 includes a determination device that determines a large number of signals from various sensors that detect the operating state of the engine and issues a valve operation stop signal or a valve operation signal, and a determination device that outputs a valve operation stop signal or a valve operation signal. After receiving the ignition signal issued by the camshaft position sensor 38, which detects the ignition timing of each cylinder from the rotational phase of the camshaft, the ignition signal for cylinders 1 and 4, which are always operated, is identified and the ignition signal is activated. The engine rotational phase detection device includes an ignition signal detector that counts the order of ignition signals for each cylinder based on the signals and provides a hydraulic pressure switching command to the hydraulic pressure switching devices 34 and 36. The ignition signals of the deactivated cylinders 2 and 3 whose order is counted by this ignition signal detector are used to stop or restore fuel injection to the same cylinders by the injectors 16 and 18.

Next, the detailed structure of the valve actuation stop mechanisms 24, 26, 28 and 30 will be explained with reference to FIGS. 2 to 4. Note that all of these valve operation stop mechanisms have the same structure.

The valve operation stop mechanism is provided in a locking arm 40 that forms part of the valve train for driving the intake valve and exhaust valve. A cylinder 42 is attached to the left arm, and a cylindrical plunger 44 with a bottom is slidably fitted into the cylinder.
including. A spring 46 interposed between the cylinder 42 and the plunger 44 moves the plunger to the second position.
By pressing downward in the figure, the bottom surface of the lower end is brought into contact with the valve shaft end of an intake valve and an exhaust valve (not shown). Two elongated holes 48 are provided in the cylindrical wall of the cylinder 42, facing each other at positions adjacent to the upper end of the plunger 44 when the plunger 44 is at the lowest position relative to the cylinder (the position shown). As shown in FIG. 3, a stopper 50 having a fork-shaped left end portion is inserted into the elongated hole 48. The forked portion of the stopper 50 has an inner edge formed in a cylindrical shape with a diameter slightly larger than the outer diameter of the plunger 44 at the left portion, and is spaced apart by a distance approximately equal to the inner diameter of the plunger at the right portion. ing. Further, a hook-shaped portion having a substantially C-shape is formed at the right end portion of the stopper 50. A screw is formed on the upper outer surface of the cylinder 42, and a double nut 52 that guides the upper surface of the stopper 50 to smoothly slide the stopper 50 is screwed onto the screw. A presser spring 54 is interposed to prevent vertical vibration of the stopper.

The valve actuation stop mechanism also includes a hydraulic actuator 62 consisting of a cylinder 56, a piston 58 that slides within the cylinder, and a return spring 60 that presses the piston into the cylinder 56. One end of a rod 64 is fixed to. A connecting member 66 is fixed to the other outer end of the rod 64, and a C-shaped hook-shaped portion of the stopper 50 surrounds the connecting member 66 with a gap 68 along the sliding direction of the piston 58. This causes the stopper 50 and rod 64 (piston 5
8) are connected with a gap 68 between them.

The valve actuation stop mechanism further includes control means for causing movement of the stopper 50 by the actuator 62 to begin immediately after the end of the cam lift, and a notch 70 is provided in the middle of the cylindrical wall of the piston 58; One end of timing plate 72 can engage the notch. The timing plate 72 is rotatably supported on a shaft 74 attached to the rocker arm 40, and slides in a groove 76 provided above the outside of the cylinder 56 to connect to the outer end of the piston 58 (see FIG. 2). left) and cut 7
It is designed so that it can be engaged with 0. Further, the timing plate 72 is biased in the piston engaging direction (clockwise in FIG. 4) by a spring 78, and a timing cam follower 80 having a substantially cylindrical shape
When the piston 58 is moved upward in FIG. 4, it is rotated counterclockwise and disengaged from the piston 58. The timing cam follower 80 moves the lock shaft 82 in response to the rocking arm 40.
The rocker arm 40 is configured to follow a timing cam 84 formed by scraping a part of the outer peripheral surface along the circumferential direction, and when the rocker arm 40 swings at or near the maximum (cam lift is at or near the maximum) ), the timing cam follower 80 can be largely slid outward in the radial direction of the camshaft 82.

Note that the cylinder 56 of the actuator 62 is
Regardless of the rocking of the rocker arm 40, the oil passage 86 and rocker shaft 82 provided in the rocker arm
It is constantly in communication with an axial oil passage 90 of the rocker shaft via a radial oil passage 88 provided in the shaft. The oil passage 90 is connected to one of the hydraulic switching devices 34 or 36.
is communicated with.

The operation of the valve actuation stop mechanism having the above structure will be explained with reference to FIGS. 5a to 5h. In addition, each of the above figures shows the structure in a simplified manner so that the principle of operation can be more clearly understood.

In FIG. 5a, hydraulic pressure is not supplied to the actuator 62, and the piston 58 returns to the spring 6.
Due to the pressing force of 0, the engagement between the plunger 44 and the stopper 50 is released when the plunger 44 is at the innermost position (leftmost position), allowing the plunger to slide and stopping the operation of the intake valve and exhaust valve. It shows the state in which In this state, the timing plate 72 and the outer end (right end) of the piston 58 are engaged.

From this state, the electric control device 2 operates the intake valve and exhaust valve according to the operating state of the engine.
2, the hydraulic pressure switching device 34,
36 supplies hydraulic pressure to the actuator 62,
The piston 58 is pushed to the right by the hydraulic pressure, but
As shown in FIG. 5b, during the period when the cam 92 is not lifted, the timing plate 7
2 is engaged with the outer end of the piston 58, so that
The piston cannot slide. After that, when the cam 92 lifts and reaches the maximum value or its vicinity,
As shown in FIG. 5c, the rocker arm 40 swings, and the timing cam follower 80 follows the timing cam 84 and slides outward in the radial direction, moving the timing plate 72 to the position indicated by the chain line in FIG. As the piston 58 is rotated, the outer end of the piston 58 disengages from the timing plate, and the piston 58 is pushed to the right by hydraulic pressure. However, in this state,
Since the cam lift occurs and the rocker arm 40 is oscillated, and the plunger 44 is slid into the cylinder 42, the stopper 50 hits the cylindrical wall surface of the plunger 44 and cannot slide. Therefore, the piston 58 slides by the size of the gap 68 provided at the connection portion with the stopper 50, and reaches a position where the timing plate 72 and the outer end of the piston do not engage. Thereafter, when the cam lift is completed, the plunger 44 is slid downward outside the cylinder 42 by the pressing force of the spring 46, and its upper end is connected to the elongated hole 4, as shown in FIG. 5d.
8, the stopper 50 becomes slidable, and as the piston 58 moves rightward due to hydraulic pressure, the stopper 50 enters the elongated hole 48 and abuts and engages with the upper end of the plunger 44, thereby removing the plunger. sliding is prevented. As a result, when a cam lift occurs next and the rocker arm 40 is swung, the plunger 44 cannot slide, so the intake valve and the exhaust valve are operated.

In addition, in this state, as shown in Figure 5e,
When no cam lift is occurring, the timing plate 72 is engaged with the notch 70 in the piston 58.

From the state shown in FIG. 5e, when the hydraulic pressure switching devices 34 and 36 discharge hydraulic pressure from the actuator 62 in response to a hydraulic pressure switching command from the control device 22 in order to stop the operation of the intake valve and exhaust valve according to the operating state of the engine. , the piston 5 by the return spring 60
8 is pushed to the left, but as shown in FIG. Can't slide. Thereafter, when the cam 92 lifts to the maximum value or near it, the rocker arm 40 swings and the timing cam follower 80 follows the timing cam 84 and moves outward in the radial direction, as shown in FIG. 5g. Since the timing plate 72 is rotated to the position indicated by the chain line in FIG. 4, the notch 70 of the piston 58 and the timing plate 7
2, and the piston 58 is pushed leftward by the pushing force of the return spring 60. However, in this state, the locker arm 40 swings and operates the intake valve and exhaust valve before the engagement is disengaged, so the stopper 50 is located between the upper end of the plunger 44 and the upper surface of the elongated hole 48. It is held in place by the spring load and cannot slide. Therefore, piston 5
8 is a gap 68 provided at the connection part with the stopper 50.
The notch 70 of the piston and the timing plate 72 are at a position where they do not engage with each other. After that, when the above cam lift is completed, the fifth
As shown in FIG. 44 sliding movements are possible. As a result, even if a cam lift occurs next time and the rocker arm 40 is swung, the plunger 44 will slide, so the operation of the intake valve and exhaust valve will be stopped.

Next, the operation of the operating cylinder number control engine having the above structure will be explained with reference to FIG. In addition, in Fig. 6, the firing order of the engine cylinders is cylinders 1-3.
-4-2, the solid line is the intake valve cam lift, and the chain line is the exhaust valve cam lift.

As mentioned above, the switching timing of the valve operation stop mechanism is prepared when the first cam lift occurs after the switching command is issued from the control device 22 and reaches the maximum value or its vicinity (see Fig. 5c). or (see g), the switching operation is set to be performed immediately after the cam lift ends. However, the switching operation of the valve actuation stop mechanism is affected by the time delay in transmitting and discharging hydraulic pressure via the hydraulic switching devices 34 and 36, so if a switching command is issued just before a cam lift occurs, the next cam lift will be delayed. Since the switching operation of the valve operation stop mechanism is performed when this occurs, the control timing of the engine according to the present invention is set in consideration of the above-mentioned hydraulic pressure transmission and discharge time delay.

Regarding the second cylinder 2, when the engine is operated with cylinders inactive, the determination device in the electrical control device 22 determines a large number of signals representing the operating state of the engine every time an ignition signal is generated from the camshaft position sensor. , it is assumed that the valve operation stop signal is issued at the time indicated by the broken line in FIG. At this point, cylinder 2
The cam lift of the intake valve occurs and the intake stroke begins. After this valve operation stop signal is generated, the ignition signal detector counts the order of the ignition signals from the camshaft position sensor 38, and detects the ignition signal of the other cylinder 4 that occurs in the latter half of the intake stroke of the cylinder 2 to be deactivated. A hydraulic switching command is given to the first hydraulic switching device 34 in synchronization, and this hydraulic switching device controls the valve actuation stop mechanisms 24 and 2.
The hydraulic pressure is discharged from 8 to bring the mechanism into the state shown in FIG. 5f. Thereafter, ignition and combustion occur in the cylinder 2, and the control device 22 controls the operation of the injector 16 to stop the injection of fuel in synchronization with this ignition signal. Then point EO
cam lift of the exhaust valve occurs, the exhaust valve begins to open, and exhaust gas is normally discharged. When the cam lift of the exhaust valve reaches or is close to the maximum value, the valve operation stop mechanism 28 enters the state shown in Fig. 5g, and immediately after the exhaust valve cam lift ends at point EC, the mechanism 28 enters the state shown in Fig. 5h. Then, in the latter half of the suction stroke, the exhaust valve stops operating. At point IO immediately before point EC, a cam lift of the intake valve occurs, the intake valve begins to open, and air is taken in. Similar to the exhaust valve, when the cam lift of the intake valve reaches or is close to the maximum value, the valve operation stop mechanism 24 enters the state shown in FIG. The state shown in FIG. 5h is reached, and the operation of the intake valve is completely stopped before and after ignition starts. During this intake stroke, since fuel injection is stopped by the control device 22, only air is sucked into the cylinder, and even if ignition occurs, no combustion occurs. After that, even if a cam lift occurs, the exhaust valve and the intake valve are deactivated and held in the closed position, so only air is trapped in the cylinder.

Conversely, in the case of restoring normal operation of the engine, suppose that the determination device within the control device 22 determines a number of signals representing the operating state of the engine and issues a valve actuation signal at the point indicated by the broken line in FIG. , After this signal is generated, the ignition signal detector counts the order of ignition signals from the camshaft position sensor, and detects the occurrence of the ignition signal in the other cylinder 4 in the latter half of the intake stroke of cylinder 2, which has been deactivated.
In synchronization with the ignition signal, a hydraulic pressure switching command is given to the first hydraulic pressure switching device 34 to supply hydraulic pressure to the valve actuation stop mechanisms 24 and 28, thereby bringing the mechanisms into the state shown in FIG. 5b. Thereafter, when the cam lift of the exhaust valve occurs at point EO and reaches the maximum value or near it, the valve operation stop mechanism 28 enters the state shown in FIG. The state shown in FIG. d is reached, and the exhaust valve returns to operation in the second half of the suction stroke. During the exhaust stroke, the exhaust valve is held in the closed position, so
Air trapped within the cylinder is not vented. When the cam lift of the intake valve occurs at point IO immediately before point EC and reaches the maximum value or near it, the valve operation stop mechanism 24 enters the state shown in Fig. 5c, and immediately after the cam lift of the intake valve ends at point IC. 24 is in the state shown in FIG. 5d, and the return to operation of the intake valve is completed before and after ignition starts. Since the intake valve is held in the closed position during the intake stroke, no air is drawn in. Then cylinder 2
The ignition takes place. Since only air is present in the cylinder, no combustion takes place. However, the control device 22 controls the operation of the injector 16 so as to restore fuel injection in synchronization with this ignition signal. Then, when the next exhaust valve cam lift occurs, the exhaust valve is activated to discharge the air trapped in the cylinder during cylinder deactivation, and when the intake valve cam lift occurs, the intake valve is activated. While air is taken in, fuel is injected by the operation of the injector 16, and normal operation is resumed.

The cylinder deactivation operation and return to normal operation in the third cylinder 3 are performed in the same manner as in the second cylinder 2 described above, so the explanation thereof will be omitted.

As described above, according to the engine that controls the number of operating cylinders according to the present invention, the exhaust valves of the second and third cylinders 2 and 3 stop operating before the intake valves when switching to cylinder deactivation operation or return to normal operation. or is configured to be restored. Therefore, when switching to cylinder deactivation operation, the exhaust valve is first held in the closed position and only the amount of air equal to the volume of the cylinder is trapped inside the cylinder, so the cylinder internal pressure does not become negative pressure and the piston As this trapped air is compressed during the upward stroke, the piston ring attached to the piston is stretched and can scrape off the oil adhering to the inner wall of the cylinder. As a result, suction of oil into the cylinder and combustion of the suctioned oil upon return to operation are prevented, so oil consumption, accumulation of carbon sludge, and generation of harmful exhaust gas components can be reduced as much as possible. Further, the control device 22 is configured to stop combustion injection by the injector in synchronization with an ignition signal before the occurrence of a cam lift of the exhaust valve at which the operation of the exhaust valve is stopped. As a result, when the intake valve cam lift occurs and the air-fuel mixture is sucked in and combusted during the intake stroke, the combustion gases are not exhausted because the exhaust valve operation is stopped. The combustion gas is trapped in the cylinder, and the compression force during the subsequent compression stroke must be extremely large, which not only causes shock, but also risks damaging engine parts due to corrosive components contained in the combustion gases. However, the engine according to the present invention eliminates such problems. Furthermore, when switching to normal operation, the exhaust valve is restored to operation first, and the air trapped in the cylinder is discharged first during the exhaust stroke immediately after restoration.
During the subsequent intake stroke, the intake of new air or mixture due to the blowback of the trapped air is not interfered with, and sufficient new air or mixture is sucked into the cylinder, allowing smooth operation. It has the advantage of being covered.

Figures 7 to 9 show other embodiments of the valve operation stop mechanism, and this embodiment is similar to Figures 2 to 4 in that a plunger is disposed at the cam side contact portion of the rocker arm. This is different from a valve operation stop mechanism. In this embodiment, elements similar to those in FIGS. 2-4 are given the same reference numerals.

In FIGS. 7 to 9, the valve operation stop mechanism has the left arm in FIG. 7 in contact with the valve shaft ends of the intake valve and exhaust valve via an adjuster screw 100 and a lock nut 102. Lotsuka arm 40
Cylinder 42 attached to the right arm in Fig. 7
and a bottomed cylindrical plunger 44 which is slidably fitted into the cylinder and has its bottom abutted against a cam, and a seventh plunger which is interposed between the cylinder 42 and the plunger 44. It includes a spring 46 that presses downward in the figure. Semicircular plate key 104
extends through cylinder 42 and into the right arm and plunger 44 to prevent relative rotation therebetween. Two elongated holes 48 are provided in the cylindrical wall of the cylinder 42, facing each other at positions adjacent to the upper end of the plunger 44 when the plunger 44 is at the lowest position relative to the cylinder (the position shown). As shown in FIG. 8, a stopper 50 substantially in the shape of a forked fork is inserted into the elongated hole 48. The fork portion of the stopper 50 is formed such that the distance between its inner edges is approximately equal to the inner diameter of the plunger 44 at the left portion and slightly larger than the outer diameter of the plunger at the right portion.

The valve actuation stop mechanism is also provided with a hydraulic actuator 62 consisting of a cylinder 56 and a piston 58 that slides within the cylinder. One end of a rod 64 is fitted into the piston 58, and a return spring 60 is interposed between the rod 64 and the cylinder 56 to press the piston and rod to the left in FIG. The other end of the rod 64 is bifurcated, and the left end of the stopper 50 is accommodated between the legs of the fork. A circular slot 108 connects the stopper and the rod with a gap 110 along the sliding direction of the stopper.

The valve actuation stop mechanism further includes a control means for starting the movement of the stopper 50 by the actuator 62 immediately after the end of the lift of the cam, and has one end mounted on one side of the rocker arm 40 on a pivot shaft 112 extending through the rocker arm. The movably pivoted timing plate 114 has at its other end a catch 118 bent at a generally right angle and extending into an axial slot 116 formed in the plunger 44. Plunger 44 is cylinder 42
slot 11 when sliding into the inside of the
6 and is pressed upward. The timing plate 114 also has another catch 120 extending over the rod 64 at its generally central portion, which stops when the rod 64 is in the rightmost position shown in FIG. It can engage the recess 122 formed therein and engage the right end surface of the rod 64 when moved to the leftmost position. The timing plate 114 further includes a protrusion 124 that engages with a timing cam 84 formed on the outer peripheral surface of the rocker shaft 82. This protruding portion moves toward the timing plate 11 in response to the rocking of the rocker arm 40.
4 constitutes a timing cam follower that swings. A leaf spring 126 fixed to the cylinder 42 has one end attached to the locking portion 1 of the timing plate 114.
20 and press the locking part downward,
The other end extends downward along the cylinder 42 and engages with the lower surface of the stopper 50 to press the stopper upward and prevent vertical vibration of the stopper.

The operation of the valve operation stop mechanism having this structure will be explained.

7 to 9, hydraulic pressure is communicated to the actuator 62 through oil passages 90, 88, and 86 via the hydraulic switching device 34 or 36, and the piston 58 and rod 64 are positioned in the rightmost position by the hydraulic pressure. , shows a state in which the stopper 50 engages with the upper end of the plunger 44, preventing sliding of the plunger 44 and operating the intake valve and exhaust valve.

From this state, the oil passages 86 and 88 are switched by the switching operation of the hydraulic switching device according to the operating state of the engine.
When the hydraulic pressure in the actuator 62 is discharged through the actuator 64 and 90, the rod 64 and the piston 58 are pushed to the left by the return spring 60, but the timing plate 114 is not engaged during the period when cam lift is not occurring. Since the stop 120 engages a recess 122 in the rod, the rod cannot slide to the left. Next, when the cam lift occurs and reaches a maximum value or near it, the rocker arm 40 rotates counterclockwise, and the protrusion 124 of the timing plate 114 follows the timing cam 84 to rotate the timing plate in a reverse direction about the pivot shaft 112. Since the timing plate is rotated clockwise, the locking portion 120 of the timing plate disengages from the recess 122 of the rod, and the rod 64 is pressed to the left by the pressing force of the return spring 60. However, in this state,
Since the locker arm 40 swings to operate the intake and exhaust valves before the engagement is disengaged, the stopper 50 is held between the upper end of the plunger 44 and the upper surface of the elongated hole 48 by the valve spring load. It cannot be slid. Therefore, the piston 58 and the rod 64 slide by the size of the gap 110 provided at the connecting portion with the stopper 50, and are brought to a position where the recess 122 of the rod and the locking portion 120 of the timing plate do not engage. Thereafter, when the cam lift is completed, the stopper 50 is released from the valve spring load and becomes slidable, so that the stopper 50 is pulled out from the elongated hole 48 as the piston 58 and rod 64 are moved leftward by the return spring 60. When the plunger 44 is released, the plunger 44 can be slid. As a result, even if a cam lift occurs next time, since the intake valve, exhaust valve, and rocker arm 40 are biased by the valve spring, which is stronger than the spring 46, the plunger 44 will only slide relative to the cylinder 42. The rocker 40 is not swung, and the operation of the intake valve and exhaust valve is stopped.

When hydraulic pressure is supplied into the actuator 62 through the oil passages 80, 88 and 86 by the switching operation of the hydraulic pressure switching device according to the operating state of the engine, the piston 58 and the rod 64 are pushed to the right by the hydraulic pressure. However, since the locking portion 120 of the timing plate 114 engages with the right end surface of the rod 64, the rod cannot slide to the right. Next, when the cam lift occurs and is at or near the maximum value, the plunger 44 is slid into the cylinder 42 and the slot 116 formed in the plunger is slid into the cylinder 42.
The lower edge of is the locking portion 1 of the timing plate 114.
18 and presses upward to rotate the timing plate counterclockwise about the pivot 112, the locking portion 120 of the timing plate disengages from the right end surface of the rod 64, and the rod is released by hydraulic pressure. Pressed to the right. However, in this state, the cam lift occurs and the plunger 44 is slid into the cylinder 42, so the stopper 50 hits the cylindrical wall surface of the plunger 44 and cannot slide. Therefore, the piston 58 and the rod 64 are connected to the stopper 50 through the gap 1 provided at the connecting portion.
The timing plate slides by a distance of 10, and reaches a position where the locking portion 120 of the timing plate and the right end surface of the rod 64 do not engage. Thereafter, when the cam lift is completed, the plunger 44 is slid outwardly and downwardly of the cylinder 42 by the pressing force of the spring 46.
Since its upper end is located below the upper surface of the elongated hole 48, the stopper 50 can slide, and as the piston 58 and rod 64 move to the right due to hydraulic pressure, the stopper 50 enters the elongated hole 48, and the plunger 44
abuttingly engages the upper end of the plunger to prevent sliding of the plunger. As a result, the next time a cam lift occurs,
Since the plunger 44 cannot slide relative to the cylinder 42, the intake and exhaust valves are operated.

Even if the valve operation stop mechanism having the above structure is used, the engine with controlled number of cylinders in operation is operated in the same manner as described above, and the same effects are achieved.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of an engine that controls the number of operating cylinders according to the present invention, FIG. 2 is a sectional view taken along the line of FIG. 3 is a partial sectional view of the rocker arm, FIG. 4 is a sectional view taken along the line of FIG. 3, FIGS. 7th graph of the relationship between the crank rotation angle, the cam rotation angle, and the cam lift showing the opening/closing timing of the exhaust valve and the ignition timing.
The figure is a sectional view taken along the line of FIG. 8 of the locker arm showing another embodiment of the valve operation stop mechanism, FIG. 8 is a partial cross-sectional view of the locker arm of FIG. - is a sectional view along the line. 1, 2, 3, 4...Cylinder, 14, 16, 18, 2
0... Injector, 22... Electrical control device, 2
4, 26, 28, 30...Valve operation stop mechanism, 32...
Hydraulic source, 34, 36... Hydraulic switching device, 38... Camshaft position sensor, 40... Locker arm, 4
2, 56...Cylinder, 44...Plunger, 50...
Stopper, 58... Piston, 62... Actuator, 64... Rod, 72, 114... Timing plate, 80... Timing cam follower, 82...
Lotsukashaft, 84...timing cam.

Claims (1)

[Scope of Claims] 1. A plunger that is slidably provided on the intake valve side valve operating means and the exhaust valve side valve operating means of the engine, and a plunger that is provided on each of the above-mentioned both valve operating means so that the plunger can slide. Lift of the cam occurs between an engaged position that restricts the opening and closing operations of the intake valve and the exhaust valve, and a disengaged position that allows sliding of the plunger and stops the opening and closing operations of both valves. detecting the phase of a stopper that is movable during a period in which the stopper is not engaged; an actuator that moves the stopper from one position to the other position or vice versa between the engagement position and the disengagement position; and the phase of the cam. and a valve operation stop mechanism that is a control means for starting the movement of the stopper immediately after the lift of the cam ends, a determination device that issues a valve operation stop signal or a valve operation signal depending on the operating state, and a determination device that issues a valve operation stop signal or a valve operation signal depending on the operating state. An engine for controlling the number of operating cylinders, characterized in that it is equipped with an engine rotational phase detection device that detects the rotational phase of an engine that can stop and return valve operation from an exhaust valve after a signal is generated, and gives an operation command to the actuator. 2 The engine is equipped with a fuel injection device that injects fuel into each cylinder, and the engine rotation phase detection device stops or restores the fuel injection device of the cylinder corresponding to the stoppage or return of valve operation of the intake valve and exhaust valve. An engine for controlling the number of operating cylinders according to claim 1, characterized in that the engine is configured to control the number of operating cylinders. 3. After the engine rotational phase detection device receives an ignition signal from a camshaft position sensor that detects the ignition timing of each cylinder from the rotational phase of the camshaft, and the camshaft position sensor, it identifies the ignition signal of the cylinder that is constantly activated. Control of the number of operating cylinders according to claim 1, further comprising an ignition signal detector that counts the order of ignition signals of each cylinder from the ignition signal of the lever and gives an operation command to the valve operation stop mechanism. engine.