JP2015124676A - Cylinder deactivation mechanism of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the reliability of an electromagnetic solenoid, concerning a cylinder deactivation mechanism of an internal combustion engine.SOLUTION: A cylinder deactivation mechanism of an internal combustion engine for holding an intake and exhaust valve 11 in a close state when a cylinder is not active, is equipped with a rocker shaft bracket 20 vertically moved by the rocking of a rocker arm 13; a lash adjuster 30 provided in a fixing system, inserted in a lower part of the rocker shaft bracket 20 to form a hydraulic chamber 32 with the rocker shaft bracket 20, having a piston 34 for moving upward the rocker shaft bracket 20, and provided with a check-valve 38 on the piston 34; an electromagnetic solenoid 40 provided in the fixing system, and having an electromagnetic coil 48 and a plunger 44 actuated by the electromagnetic coil 48; and a needle 50 provided on the plunger 44, extending through a hollow-hole formed on the rocker shaft bracket 20, and opening the check-valve of the lash adjuster 30.

Description

  The present invention relates to a cylinder deactivation mechanism of an internal combustion engine for holding an intake / exhaust valve provided in a cylinder of the internal combustion engine in a closed state when the cylinder is deactivated.

  Conventionally, when some cylinders of a multi-cylinder engine (internal combustion engine) are deactivated and only the remaining cylinders are operated, it is necessary to stop fuel injection into the cylinders and keep the intake and exhaust valves closed. .

  However, since the intake and exhaust valves are opened and closed in synchronization with the rotation of the crankshaft by a valve operating mechanism consisting of a rocker arm, when stopping a cylinder, the cylinder that is stopped without disturbing the driving of the valve operating mechanism Therefore, it is necessary to keep the intake and exhaust valves closed.

  Conventionally, various cylinder deactivation mechanisms have been proposed (Patent Documents 1 to 4).

  These cylinder deactivation mechanisms hold the pivot point of the rocker arm that opens and closes the intake / exhaust valves with oil pressure, and when the cylinder is deactivated, the check valve operates with an electromagnetic solenoid to release the oil pressure. Thus, the rocker arm is allowed to escape from the operating region of the cam.

  However, the rocker arm has a lash adjuster that urges the rocker arm so that the contact portion between the end of the rocker arm and the valve stem of the intake / exhaust valve always comes into contact when the contact portion with the cam is worn. It is indispensable, and Patent Documents 1 to 4 do not consider this lash adjuster.

  The present applicant is provided with a lash adjuster at the other end of the rocker arm, and the lash adjuster always holds the other end with oil pressure, and in a steady state, holds it so as to swing at the rotation center of the rocker arm. During cylinder deactivation, open the check valve of the lash adjuster with an electromagnetic solenoid to release the hydraulic pressure so that the center of rotation of the rocker arm is separated from the operating area of the cam while keeping the intake and exhaust valves closed. A cylinder deactivation mechanism was proposed.

JP 59-23018 A JP-A-60-26113 JP 60-256509 A JP-A-61-187506

  By the way, in this cylinder deactivation mechanism, in order to maintain the intake and exhaust valves in the closed state, in order to release the hydraulic pressure of the lash adjuster by the electromagnetic solenoid, it is necessary to provide an electromagnetic solenoid integrally with the other end of the rocker arm.

  However, since the rocker arm always swings with a cam even during a pause, the electromagnetic solenoid also moves up and down, so the power supply wiring section that energizes the coil also moves up and down. There is a risk that it will bend repeatedly due to up and down movements, resulting in damage that tends to be damaged and impairing reliability.

  It is an object of the present invention to provide a cylinder deactivation mechanism of an internal combustion engine that includes a lash adjuster and can improve reliability without causing the power wiring portion of the electromagnetic solenoid to move up and down when deactivating the cylinder.

  To achieve the above object, the present invention provides an intake / exhaust valve that is provided in a cylinder and is normally biased by a valve spring, and is swingably provided so that the intake / exhaust valve is opposed to the valve spring. A lash that holds the other end of the rocker arm with hydraulic pressure so that the rocker arm to be opened, the cam that swings the rocker arm, and the one end of the rocker arm and the intake / exhaust valve are always in contact with each other A cylinder deactivation mechanism for an internal combustion engine for holding the intake / exhaust valve in a closed state when the cylinder is deactivated, wherein the rocker arm and the rocker shaft are pin-connected, and the rocker arm swings Rocker shaft bracket that moves up and down at a fixed system, and is inserted into the lower part of the rocker shaft bracket and the rocker shaft A lash adjuster that forms a bracket and a hydraulic chamber, has a piston that moves the rocker shaft bracket upward, and is provided with a check valve on the piston, an electromagnetic coil provided in a fixed system, and an electromagnetic coil thereof An electromagnetic solenoid having a plunger that is actuated in step (b), and a needle that is provided in the plunger and extends through a hollow hole formed in the rocker shaft bracket and opens a check valve of the lash adjuster.

  The rocker shaft bracket includes a bracket body that is pin-coupled to a rocker shaft axis of a rocker arm, and a base mount that is provided at an upper portion of the bracket body and is biased by a spring through a spring. The hydraulic chamber that engages with the upper portion of the lash adjuster may be formed, and an oil supply passage that supplies hydraulic oil to the hydraulic chamber may be connected to the bracket body.

  The lash adjuster is provided with an adjuster body that is fitted into the bracket body to form a hydraulic chamber, a piston that is slidable up and down on the adjuster body, and that moves the rocker arm upward with hydraulic pressure. A check valve may be provided that partitions the bracket-side pressure chamber and the adjuster-side pressure chamber above the piston and communicates the bracket-side pressure chamber and the adjuster-side pressure chamber with the needle.

  The needle is attached to the plunger with a needle position adjusting screw, and when the electromagnetic solenoid is inactive, the tip is held at a position away from the check ball of the check valve, and the electromagnetic solenoid is activated, The check ball of the check valve may be pushed down at the tip thereof so that the bracket side pressure chamber and the adjuster side pressure chamber above and below the piston communicate with each other.

  According to the cylinder deactivation mechanism of the internal combustion engine of the present invention, the power wiring portion of the electromagnetic solenoid does not move up and down when deactivating the cylinder, and the reliability can be improved.

It is a typical fragmentary sectional view showing the stop state of the cylinder deactivation mechanism concerning the embodiment of the present invention. It is the sectional view on the AA line of FIG. It is a typical fragmentary sectional view showing the operating state of the cylinder deactivation mechanism concerning the embodiment of the present invention. It is typical sectional drawing which shows the principal part of the cylinder deactivation mechanism which concerns on embodiment of this invention. In the cylinder deactivation mechanism according to the conventional example, (a) is a schematic diagram of a deactivation state, and (b) is a schematic diagram of an operation state.

  Hereinafter, a cylinder deactivation mechanism of an internal combustion engine according to an embodiment of the present invention will be described with reference to the accompanying drawings.

  As shown in FIG. 1, a cylinder deactivation mechanism 10 according to the present embodiment holds an intake / exhaust valve 11 in a closed state when the cylinder is deactivated. The cylinder deactivation mechanism 10 is provided in the cylinder and is urged to a normally closed state by a valve spring 12. A rocker arm 13 that is swingably provided to open and close the intake / exhaust valve 11 against the valve spring 12, a cam 15 that rocks the rocker arm 13, and a rocker arm 13. A rocker shaft bracket 20 that is pin-connected by the rocker shaft shaft 14 and moves up and down by rocker arm 13 swinging, and the other end of rocker arm 13 so that one end of rocker arm 13 and intake / exhaust valve 11 are always in contact with each other. A lash adjuster 30 that holds the (rocker shaft bracket 20) with hydraulic pressure, and an electromagnetic solenoid 40 provided in the fixed system Needle 50 (see FIG. 4) provided in plunger 44 (see FIG. 4) extends through hollow hole 24 (see FIG. 4) formed in rocker shaft bracket 20 and opens check valve 38 (see FIG. 4) of lash adjuster 30. 4).

  The rocker shaft bracket 20 includes a bracket main body 21 pin-connected to the rocker arm 13 by a rocker shaft shaft 14, and a base mount 22 made of a magnetic material provided on the upper portion of the bracket main body 21. As shown in FIG. 2, a pair of rocker arms 13 is pin-connected to the bracket body 21 via a rocker shaft 14. As shown in FIG. 4, a through hole 25 is formed in the rocker shaft bracket 20. The needle 50 is inserted into the through hole 25.

  As shown in FIG. 4, the lash adjuster 30 is provided with an adjuster body 31 that fits into the bracket body 21 to form an adjuster-side pressure chamber 32 a of the hydraulic chamber 32, and is provided on the adjuster body 31 so as to be slidable up and down. A piston 34 that moves the arm 13 (the rocker shaft bracket 20) upward with hydraulic pressure, and a check valve 38 provided on the piston 34 are provided.

  The adjuster main body 31 is joined to a plate-like member, at least a part of which is fixed to an engine (for example, a cylinder head) with a bolt, and a cylindrical member fitted into the bracket main body 21 is joined.

  The piston 34 is formed in a cylindrical shape, the upper part is in contact with the lower part of the rocker shaft bracket 20, and the lower part is provided with an oil hole 35 that serves as a valve seat of a check valve 38 that circulates oil. The piston 34 is urged toward the bracket-side pressure chamber 32b by a piston spring 39 interposed between the piston 34 and the lash adjuster 30.

  The check valve 38 partitions the hydraulic chamber 32 into an upper bracket side pressure chamber 32b and a lower adjuster side pressure chamber 32a. Further, the check valve 38 is pushed downward by the needle 50 to open, and allows the bracket-side pressure chamber 32b and the adjuster-side pressure chamber 32a to communicate with each other. As a result, the hydraulic pressure in the adjuster side pressure chamber 32a is lowered, the rocker shaft bracket 20 is allowed to move up and down, and the intake / exhaust valve 11 is closed (see FIG. 1). On the other hand, the check valve 38 is closed by closing the oil hole 35 with the check ball 38b urged by the check ball spring 33, and shuts off the bracket side pressure chamber 32b and the lower adjuster side pressure chamber 32a. . As a result, the hydraulic pressure in the adjuster side pressure chamber 32a is increased, the movement of the rocker shaft bracket 20 is restricted, and the rocker shaft 14 is held so that the intake / exhaust valve 11 is opened and closed (see FIG. 3).

  The electromagnetic solenoid 40 is provided with an electromagnetic coil 48 provided in a fixed system, a plunger 44 made of a magnetic body operated by the electromagnetic coil 48, and the influence of the magnetic field of the electromagnetic coil 48. A holder 43 made of a non-magnetic material such as stainless steel for accommodating the upper portion of the mount 22, a mold 47 for accommodating the electromagnetic coil 48, and a power supply wiring portion 49 for supplying current to the electromagnetic coil 48. When the plunger 44 and the base mount 22 are magnetized by the generated magnetic field, they are actuated downward as shown in FIG.

  The plunger 44 has a lower cylinder part 44a and an upper cylinder part 44b. A plunger spring 45 that urges the plunger 44 toward the top of the holder 43 is interposed in the cylinder of the lower cylinder portion 44a. A needle position adjusting screw 46 is screwed into the cylinder of the upper cylinder portion 44b. A needle 50 for opening the check valve 38 is provided at the lower end of the needle position adjusting screw 46.

  The holder 43 is formed in a cylindrical shape, and the base mount 22 is fitted in the cylinder on the lower end side. A plunger 44 is housed in a cylinder above the base mount 22 of the holder 43 so as to be movable up and down.

  The needle 50 is attached to the plunger 44 with a needle position adjusting screw 46, and when the electromagnetic solenoid 40 is inactive, the tip of the needle 50 is held at a position away from the check ball 38b of the check valve 38. On the other hand, when the electromagnetic solenoid 40 is activated, the check ball 38b of the check valve 38 is pushed down at its tip to open the valve.

  The mold 47 accommodates the holder 43 so as to be movable up and down. The mold 47 is provided with an electromagnetic coil 48 so as to surround the holder 43. A power supply wiring portion 49 is connected to the electromagnetic coil 48.

  Next, the effect of the cylinder deactivation mechanism 10 according to this embodiment will be described.

  In the conventional example, as shown in FIG. 5 (b), when the intake / exhaust valve 63 is closed, the electromagnetic solenoid 65 is connected to the other end of the rocker arm 62 so as to release the hydraulic pressure of the lash adjuster 64. 65 is provided integrally. However, since the rocker arm 62 always swings with the cam 61, the electromagnetic solenoid 65 also moves up and down. For this reason, since the power supply wiring part 66 which supplies with electricity to the coil which is not shown in figure also moves up and down, the power supply wiring part 66 is repeatedly bent by the up-and-down movement, and there exists a possibility that a malfunction may arise and reliability may be impaired.

  On the other hand, in this embodiment, as shown in FIG. 3, when the normal intake / exhaust valve 11 is opened and closed, the rocker shaft bracket 20 is pushed upward by the oil pressure of the lash adjuster 30, and the rocker shaft shaft 14 is The arm 13 is held at a position where one end of the arm 13 is in contact with the upper end of the intake / exhaust valve 11.

  In this state, the operation of the cam 15 causes the rocker arm 13 to swing around the rocker shaft 14 to open and close the intake / exhaust valve 11.

  Further, at the time of cylinder deactivation, when the cylinder deactivation mechanism 10 maintains the closed state of the intake / exhaust valve 11, a current is supplied from the power supply wiring portion 49 of the electromagnetic solenoid 40 to the electromagnetic coil 48 to excite the needle 50. Accordingly, the check valve 38 is opened to release the hydraulic pressure on the adjuster side pressure chamber 32a side. In this state, the rocker arm 13 is removed from the operating region of the cam 15, and the intake / exhaust valve 11 is held in the closed state by the valve spring 12. In this case, the rocker arm 13 reciprocates slightly up and down together with the rocker shaft bracket 20. The holder 43 also moves along with this, but since the mold 47 is spaced apart from the holder 43 and fixed to the engine (for example, a head cover), the electromagnetic coil 48 and the power supply wiring portion 49 in the mold 47 do not move.

  Therefore, according to the cylinder deactivation mechanism 10 of the present embodiment, when the cylinder is deactivated, the power supply wiring portion 49 of the electromagnetic solenoid 40 does not move up and down. Therefore, reliability can be improved.

10 Cylinder deactivation mechanism 11 Intake / exhaust valve 12 Valve spring 13 Rocker arm 14 Rocker shaft shaft 15 Cam 20 Rocker shaft bracket 21 Bracket body 22 Base mount 23 Oil supply path 30 Rush adjuster 31 Adjuster body 32 Hydraulic chamber
32a Adjuster side pressure chamber 32b Bracket side pressure chamber 33 Check ball spring 34 Piston 35 Oil hole 38 Check valve 38b Check ball 39 Piston spring 40 Electromagnetic solenoid 43 Holder (nonmagnetic material such as stainless steel)
44 Plunger 45 Plunger spring 46 Needle position adjusting screw 47 Mold 48 Electromagnetic coil 49 Power supply wiring section 50 Needle

Claims (4)

An intake / exhaust valve that is provided in the cylinder and is normally biased by a valve spring, a rocker arm that is swingably provided and opens the intake / exhaust valve against the valve spring, and the rocker arm And a lash adjuster that holds the other end of the rocker arm with hydraulic pressure so that the one end of the rocker arm and the intake / exhaust valve are always in contact with each other. A cylinder deactivation mechanism for an internal combustion engine for holding an intake / exhaust valve in a closed state,
A rocker shaft bracket that is pin-connected by the rocker arm and a rocker shaft shaft, and moves up and down by swinging the rocker arm
Provided in a fixed system, inserted into the lower part of the rocker shaft bracket to form a hydraulic chamber with the rocker shaft bracket, and has a piston that moves the rocker shaft bracket upward, and a check valve is provided in the piston Rush adjuster,
An electromagnetic solenoid provided in a fixed system, having an electromagnetic coil and a plunger operated by the electromagnetic coil;
A cylinder deactivation mechanism for an internal combustion engine, comprising: a needle provided on the plunger and extending through a hollow hole formed in the rocker shaft bracket and opening a check valve of the lash adjuster.   The rocker shaft bracket includes a bracket body that is pin-coupled to a rocker shaft axis of a rocker arm, and a base mount that is provided at an upper portion of the bracket body and is biased by a spring through a spring. 2. The cylinder deactivation mechanism of the internal combustion engine according to claim 1, wherein the hydraulic chamber that is fitted to an upper portion of the lash adjuster is formed, and an oil supply passage that supplies hydraulic oil to the hydraulic chamber is connected to the bracket body.   The lash adjuster is provided with an adjuster body that is fitted into the bracket body to form a hydraulic chamber, a piston that is slidable up and down on the adjuster body, and that moves the rocker arm upward with hydraulic pressure. 3. A cylinder of an internal combustion engine according to claim 2, further comprising a check valve that is provided and is divided into a bracket-side pressure chamber and an adjuster-side pressure chamber at an upper part of the piston and that communicates the bracket-side pressure chamber and the adjuster-side pressure chamber by the needle. Pause mechanism.   The needle is attached to the plunger with a needle position adjusting screw, and when the electromagnetic solenoid is inactive, the tip is held at a position away from the check ball of the check valve, and the electromagnetic solenoid is activated, 4. A cylinder deactivation mechanism for an internal combustion engine according to claim 3, wherein the check ball of the check valve is pushed down at its tip to communicate the bracket side pressure chamber and the adjuster side pressure chamber above and below the piston.