JP2010116797A - Valve gear for internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a valve gear for an internal combustion engine, achieving reduction in fuel consumption and cleaning of exhaust gas by operating an intake valve and an exhaust valve at the optimum opening/closing timing and during a valve opening period, and reducing noise, production cost and maintenance cost by simplifying a structure. <P>SOLUTION: This valve gear 1 for the internal combustion engine includes a hydraulic control valve 14 controlling operations of an intake valve actuator 12 and an exhaust valve actuator 11. A spool valve 53, a seat valve 62 and a gate valve 73 are provided inside the hydraulic control valve 14. The spool valve 53 controls the opening/closing of an opening 71 by the seat valve 62. A hydraulic control chamber 79 is partitioned between the gate valve 73 and a second storage chamber 75. When the seat valve 62 opens the opening 71, high-pressure hydraulic fluid is supplied into the hydraulic control chamber 79, and the gate valve 73 is lifted. When the seat valvae 62 closes the opening 71, pressure in the hydraulic control chamber 79 is released, and the gate valve 73 is lowered. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a valve operating apparatus for an internal combustion engine, and more particularly to a configuration for opening and closing an intake valve and an exhaust valve using hydraulic pressure.

  In a general internal combustion engine, an intake valve and an exhaust valve are opened and closed by rotating a cam having a predetermined cam profile. For example, according to the internal combustion engine described in Patent Document 1, a crankshaft and a cam are connected via a gear, and the cam is rotated by being driven by the crankshaft. The rotating cam swings the rocker arm via a tappet and a push rod that reciprocate along the cam profile, and the swinging rocker arm opens and closes the intake valve and the exhaust valve.

Japanese Patent Laid-Open No. 11-229821

  Here, in the intake valve and the exhaust valve of the internal combustion engine, their optimum opening / closing timing and valve opening period vary depending on the engine rotational speed, load and the like of the internal combustion engine. However, the intake valve and the exhaust valve in the internal combustion engine described in Patent Document 1 open and close along the profile of the cam regardless of these situations. That is, depending on the situation, the intake valve and the exhaust valve do not open and close at the optimal time and period, and thus there is a problem that it is difficult to reduce fuel consumption and clean exhaust gas.

  In addition, since the tappet, push rod, and rocker arm that follow the cam operate at an acceleration that varies according to the cam profile, the inertial force becomes the largest when the maximum acceleration is generated. That is, in order to prevent these parts from being damaged when operating at the maximum acceleration during high-speed operation, it is necessary to increase the rigidity of the parts themselves. However, if the rigidity of the parts is increased, the weight also increases, resulting in a problem that mechanical loss increases and fuel consumption deteriorates.

  Further, when the intake valve and the exhaust valve are opened and closed via the rocker arm, the occurrence of outgassing on the valve seating surface due to the thermal expansion of the intake valve and the exhaust valve during operation of the internal combustion engine is prevented. Therefore, it is common to provide a gap between the valve stem and the rocker arm. However, this gap has a problem in that the rocker arm and the valve stem strike each other, and a very loud noise is generated.

  Further, when the power for driving the cam is taken out from the crankshaft via the gear, especially in a four-cycle engine, it is necessary to reduce the rotational speed of the cam to half the rotational speed of the engine, so that the gear train is complicated. As a result, it is difficult to reduce the manufacturing cost, and gear noise is generated.

  The present invention has been made to solve such problems, and operates the intake valve and the exhaust valve at an optimal opening / closing timing and valve opening period to reduce fuel consumption and clean exhaust gas, It is an object of the present invention to provide a valve operating apparatus for an internal combustion engine with a simplified structure and reduced noise, manufacturing cost and maintenance cost.

  A valve operating apparatus for an internal combustion engine according to the present invention includes a hydraulic pressure source that boosts and discharges hydraulic oil in a tank, and an intake valve that opens and closes the intake valve of the internal combustion engine by operating with hydraulic oil supplied from the hydraulic source An exhaust valve actuator for opening and closing the actuator and the exhaust valve, a hydraulic control valve provided between the hydraulic source and the intake valve actuator, and a hydraulic control valve provided between the hydraulic source and the exhaust valve actuator. a) A first storage chamber in which an output port connected to the intake valve actuator or the exhaust valve actuator and a discharge port connected to the tank are formed, and an end of the first storage chamber communicate with each other through an opening. A control valve body having a second storage chamber in which a supply port connected to a hydraulic pressure source is formed, and (b) a seat valve slidably provided in the first storage chamber, When opening and closing, the output port and the discharge port are shut off, and when the opening is closed, the output port and the discharge port are switched. (C) a slidable valve that is slidably provided in the second storage chamber, and divides the second storage chamber into an opening portion side and a supply port side; and (d) an opening portion of the partition valve. The gate valve has a large-diameter portion arranged on the opening portion side, an outer diameter smaller than the large-diameter portion, a small-diameter portion arranged on the supply port side, and a large-diameter And an intermediate portion that divides the hydraulic control chamber from the second storage chamber and penetrates from the supply port side in the second storage chamber to the opening side in the second storage chamber. A through-hole that is provided in the through-hole, and the second accommodation from the supply port side in the second accommodation chamber The hydraulic control chamber is connected to the opening when the seat valve opens the opening, and the seat valve opens to the opening. When the is closed, it is connected to the discharge port.

  When the opening is closed by the seat valve, the output port communicates with the discharge port, so that the hydraulic oil in the intake valve actuator or exhaust valve actuator is returned to the hydraulic control valve, and the intake valve and exhaust valve are closed. Can do. Moreover, the hydraulic fluid which circulated through the through-hole of the gate valve flows into the opening portion closed by the seat valve. When the opening is closed, the hydraulic control chamber and the discharge port communicate with each other, so the hydraulic control chamber is opened, whereby the gate valve moves to the supply port side, and the inside of the opening and the second storage chamber A predetermined amount of hydraulic oil having a predetermined hydraulic pressure is stored on the opening side.

  On the other hand, when the opening is opened by the seat valve, since the opening is communicated with the output port, high-pressure hydraulic oil is supplied into the intake valve actuator and the exhaust valve actuator, and the intake valve and the exhaust valve are opened. . In addition, when the opening is opened, high-pressure hydraulic oil flows into the hydraulic control chamber, so the gate valve moves to the opening side by the spring force of the gate valve spring and reliably sucks a predetermined amount of hydraulic oil. Supply securely to the valve actuator or exhaust valve actuator.

  The opening and closing of the opening by the seat valve can be controlled by, for example, using hydraulic pressure and by an electric signal based on an angle signal from the crankshaft, so that optimum control according to the operating condition of the internal combustion engine is possible. . In addition, it is not necessary to use cams, tappets, push rods, and rocker arms to open and close the intake and exhaust valves, and it is not necessary to extract driving force from the crankshaft using gears. It can be simplified. Therefore, in a valve operating device for an internal combustion engine, the intake valve and the exhaust valve are operated at an optimal opening / closing timing and valve opening period to reduce fuel consumption and clean exhaust gas, and simplify the structure to reduce noise and manufacturing costs. In addition, maintenance costs can be reduced.

  The control valve main body communicates with the end of the first storage chamber opposite to the second storage chamber, and forms a pilot pressure supply port connected to the hydraulic pressure source and a pilot pressure discharge port connected to the tank. And a spool valve that selectively opens and closes the pilot pressure supply port and the pilot pressure discharge port to control the opening and closing of the opening by the seat valve. It may be provided so as to be movable.

  Since the pilot pressure supply port and the pilot pressure discharge port can be selectively opened and closed by moving the spool valve in the third storage chamber, the hydraulic pressure can be increased by simply operating the spool valve using, for example, an electromagnetic solenoid. The operation of the entire control valve can be controlled. In addition, since the spool valve is housed in the control valve body, it is possible to control the operation of the intake valve and the exhaust valve without complicating the structure.

  The exhaust valve actuator includes an exhaust valve actuator body having a first cylinder chamber and a second cylinder chamber connected to an output port of the hydraulic control valve, a sub-piston slidably provided in the first cylinder chamber, A main piston that is slidably provided in the two-cylinder chamber and is connected to the exhaust valve, and the sub-piston is fixed to the main body, and is fixed to the main body and in the second cylinder chamber An extending rod portion and a communication passage communicating the first cylinder chamber and the second cylinder chamber may be provided, and the main body portion may have an outer diameter larger than that of the main piston.

  Since the first cylinder chamber connected to the output port of the hydraulic control valve is provided with a sub piston having an outer diameter larger than that of the main piston, the first cylinder chamber and the second cylinder chamber communicate with each other via the communication path of the sub piston. First, the exhaust valve can be slightly opened by the large force of the auxiliary piston against the high pressure in the combustion chamber. After the exhaust valve is opened and the high pressure in the combustion chamber is released, the main piston is moved by the small flow rate of hydraulic oil flowing into the second cylinder chamber through the communication passage, so that the exhaust valve can be fully opened. Further, when the exhaust valve is closed, the hydraulic oil is compressed in the first cylinder chamber to cause a braking action, so that an impact when the exhaust valve is seated can be buffered.

  The intake valve actuator includes a small-diameter inner peripheral portion connected to the output port of the hydraulic control valve, and an intake valve actuator main body having a third cylinder chamber having a large-diameter inner peripheral portion having an inner diameter larger than that of the small-diameter inner peripheral portion. An intake piston connected to an intake valve and having an upper piston portion disposed in the small-diameter inner peripheral portion and a lower piston portion disposed in the large-diameter inner peripheral portion and slidably provided in the third cylinder chamber The intake valve side piston is provided in the communication passage penetrating from the small diameter inner peripheral portion to the large diameter inner peripheral portion, and the hydraulic oil from the small diameter inner peripheral portion to the large diameter inner peripheral portion. A non-return valve that allows only the flow of the gas, and a branch hole that branches from the communication passage and opens to the outer peripheral surface of the upper piston portion, and that moves into the inner peripheral portion of the small diameter when the intake valve is closed. Good.

  When hydraulic oil is supplied from the hydraulic control valve, the hydraulic oil flows into the large-diameter inner peripheral portion via the communication path and the check valve, and the intake valve side piston is moved by the hydraulic pressure to open the intake valve. . On the other hand, when the intake valve is closed, the hydraulic oil in the large-diameter inner peripheral portion is discharged until the branch hole moves into the small-diameter inner peripheral portion. When the branch hole moves into the small-diameter inner peripheral portion, the hydraulic oil in the third cylinder chamber is compressed to cause a braking action, so that it is possible to buffer an impact when the intake valve is seated.

  According to the present invention, in a valve operating apparatus for an internal combustion engine, the intake valve and the exhaust valve are operated at an optimal opening / closing timing and valve opening period to reduce fuel consumption and clean exhaust gas, and simplify the structure. Noise, manufacturing costs and maintenance costs can be reduced.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
Embodiment 1 FIG.
FIG. 1 schematically shows a valve gear 1 for an internal combustion engine (hereinafter abbreviated as valve gear 1) according to Embodiment 1 of the present invention.
The cylinder head 2 of the internal combustion engine to which the valve gear 1 is applied has an intake passage 2a for supplying intake air into a combustion chamber (not shown) and an exhaust passage 2b for discharging exhaust gas generated in the combustion chamber to the outside. Is formed. Further, the cylinder head 2 is provided with an intake valve 6 for opening and closing the intake passage 2a and an exhaust valve 3 for opening and closing the exhaust passage 2b. A retainer 7 is fixed to the valve stem 6 a of the intake valve 6, and the intake valve 6 is urged in a closing direction by an intake valve spring 8 provided between the cylinder head 2 and the retainer 7. . Similarly, the exhaust valve 3 is also urged in a closing direction by an exhaust valve spring 5 provided between the cylinder head 2 and a retainer 4 fixed to the valve stem 3 a of the exhaust valve 3.

  The valve operating apparatus 1 opens and closes the intake valve 6 and the exhaust valve 3 of the internal combustion engine configured as described above by using the hydraulic pressure of the hydraulic oil. The intake valve 6 is operated by the hydraulic oil. An intake valve actuator 12 is connected. An exhaust valve actuator 11 that is operated by hydraulic oil is also connected to the exhaust valve 3. Further, a hydraulic control valve 14 for controlling these operations is individually connected to the intake valve actuator 12 and the exhaust valve actuator 11 via an output path 13. The configurations of the hydraulic control valve 14, the intake valve actuator 12, and the exhaust valve actuator 11 will be described later.

  Further, the valve operating apparatus 1 includes a tank 18 in which hydraulic oil is stored. A pump 20 driven by an electric motor 19 is connected to the tank 18 via a filter 21. Here, the electric motor 19 and the pump 20 constitute a hydraulic pressure source in the valve gear 1. One end of a hydraulic oil supply path 17 is connected to the pump 20, and the hydraulic oil in the tank 18 is pressurized by the pump 20 and discharged to the hydraulic oil supply path 17. The other end of the hydraulic oil supply path 17 is connected to a common rail 16 for evenly distributing the hydraulic oil to the intake valve actuator 12 and the exhaust valve actuator 11. A check valve 22 is provided in the middle of the hydraulic oil supply path 17 to prevent the backflow of the hydraulic oil discharged from the pump 20.

  A hydraulic oil supply path 15 for each hydraulic control valve 14 is connected to the common rail 16, and each hydraulic control valve 14 and the corresponding intake valve actuator 12 and exhaust valve actuator 11 are connected via an output path 13. Has been. Each hydraulic control valve 14 is connected to one end of a branched hydraulic oil discharge path 23, and the other end of the joined hydraulic oil discharge path 23 is connected to a tank via a filter 24 and a cooler 25. ing.

Here, the configuration of the hydraulic control valve 14 will be described with reference to FIG.
The hydraulic control valve 14 includes a control valve body 51 whose longitudinal direction is indicated by an arrow in FIG. A cylindrical third storage chamber 55 extending perpendicularly to the longitudinal direction is formed in the vicinity of the upper end of the control valve main body 51, and two annular grooves are formed on the inner peripheral surface 52 thereof. 57 and 59 are formed. A pilot pressure supply port 56 is formed at the bottom of the annular groove 57, and the hydraulic oil supply path 15 is connected to the pilot pressure supply port 56. On the other hand, a pilot pressure discharge port 58 is formed at the bottom of the annular groove 59, and the hydraulic oil discharge path 23 is connected to the pilot pressure discharge port 58.

  A spool valve 53 that selectively opens and closes the pilot pressure supply port 56 and the pilot pressure discharge port 58 is slidably provided inside the third storage chamber 55. The spool valve 53 is a member having a substantially cylindrical shape in which a central portion in the axial direction is recessed, and one end portion is hollow, and a spool valve spring 54 is provided therein. The spool valve spring 54 biases the spool valve 53 in a direction that opens the pilot pressure supply port 56 and closes the pilot pressure discharge port 58. An electromagnetic solenoid (not shown) is provided at the other end of the spool valve 53. By energizing the electromagnetic solenoid, the spool valve 53 can be moved against the spring force of the spool valve spring 54 to close the pilot pressure supply port 56 and open the pilot pressure discharge port 58.

  A cylindrical first storage chamber 64 that extends with the longitudinal direction of the control valve body 51 as an axial direction is formed below the third storage chamber 55. The third storage chamber 55 and the first storage chamber 64 communicate with each other through the communication hole 60. Inside the first storage chamber 64, a seat valve 62 having a substantially cylindrical shape with a bottom that opens upward and has a bottom 62b disposed on the lower side is slidably provided. A seat valve spring 63 is provided on the inner peripheral portion of the seat valve 62 to urge the seat valve 62 downward. The inner circumferential surface 61 of the first storage chamber 64 is formed with an upper annular groove 61a and a lower annular groove 61b that are arranged vertically along the axial direction. On the other hand, in the outer peripheral surface of the seat valve 62, a concave portion 62a that is recessed radially inward is formed in a portion that faces the upper annular groove 61a and the lower annular groove 61b.

  Further, an annular groove 67 surrounding the bottom portion 62b of the seat valve 62 is formed on the lower side of the first storage chamber 64, and the lower end portion of the annular groove 67 is in contact with the bottom portion 62b of the seat valve 62. An opening 71 to be closed is formed. A discharge port 65 to which the hydraulic oil discharge path 23 is connected is formed at the bottom of the upper annular groove 61a. A connection port 66 is formed at the bottom of the lower annular groove 61 b, and the connection port 66 and the connection port 69 formed at the bottom of the annular groove 67 are connected via a connection path 82. An output port 68 to which the output path 13 is connected is formed at the bottom of the annular groove 67.

  That is, the seat valve 62 can move up and down in the first storage chamber 64 to open and close the opening 71 and switch between communication and blocking between the opening 71 and the output port 68. Further, when the seat valve 62 moves upward and opens the opening 71, the lower annular groove 61 b is blocked by the outer peripheral surface of the seat valve 62. Accordingly, since the upper annular groove 61a is also blocked by the seat valve 62, the output port 68 and the discharge port 65 are blocked. On the other hand, when the seat valve 62 moves downward and closes the opening 71, the upper annular groove 61a and the lower annular groove 61b communicate with each other through the recess 62a of the seat valve 62. Therefore, the output port 68 and the discharge port 65 communicate with each other through the annular groove 67, the connection port 69, the connection path 82, the connection port 66, the lower annular groove 61b, the recess 62a of the seat valve 62, and the upper annular groove 61a in this order. .

  A cylindrical second storage chamber 75 extending to the vicinity of the lower end portion of the control valve body 51 is formed below the opening 71 with the longitudinal direction of the control valve body 51 as the axial direction. A supply port 76 to which the hydraulic oil supply path 15 is connected is formed at the lower end portion of 75. A gate valve 73 having a bottomed, substantially cylindrical shape that opens downward is slidably provided in the second storage chamber 75, and the second storage chamber 75 is connected to the opening 71 side. It is divided into the supply port 76 side. The gate valve 73 is disposed on the upper side, that is, the side facing the opening 71, and is disposed on the large diameter portion 73c having the outer diameter D1 and on the lower side, that is, on the supply port 76 side, and is smaller than the large diameter portion 73c. A small-diameter portion 73d having a diameter D2. A gate valve spring 74 is provided on the inner peripheral portion of the gate valve 73 and biases the gate valve 73 toward the opening 71.

  A large-diameter portion 73 c that is the bottom of the gate valve 73 is formed with a through hole 73 a that penetrates from the supply port 76 side to the opening 71 side in the second storage chamber 75. In addition, a check valve 77 is provided in the through hole 73a to allow the hydraulic oil supplied into the second storage chamber 75 through the supply port 76 to flow only from the supply port 76 side to the opening 71 side. Yes. The check valve 77 includes a spherical member 77a provided in the through hole 73a and a spring 77b that urges the spherical member 77a downward, and the spherical member 77a is moved upward against the spring force of the spring 77b. When a pressure that can move to the fluid acts, the hydraulic oil is circulated to the opening 71 side.

  An intermediate portion 73b having an outer diameter smaller than the small diameter portion 73d is formed between the large diameter portion 73c and the small diameter portion 73d, and an annular groove formed on the inner peripheral surface 72 of the second storage chamber 75. The hydraulic control chamber 79 is partitioned between A connection port 80 is formed at the bottom of the annular groove 78, and one end of a connection path 81 is connected to the connection port 80. The other end of the connection path 81 is connected to a connection path 82 that communicates the annular groove 67 and the lower annular groove 61 b of the first storage chamber 64. Therefore, when the seat valve 62 opens the opening 71, the hydraulic control chamber 79 communicates with the opening 71 via the connection port 80, the connection path 81, the connection path 82, the connection port 69, and the annular groove 67. Become. When the seat valve 62 closes the opening 71, the hydraulic control chamber 79 includes the connection port 80, the connection path 81, the connection path 82, the connection port 66, the lower annular groove 61b, the recess 62a of the seat valve 62, The exhaust port 65 communicates with the upper annular groove 61a.

Next, the configuration of the exhaust valve actuator 11 will be described with reference to FIG.
The exhaust valve actuator 11 includes an exhaust valve actuator main body 31, and a connection port 37 connected to the output port 68 of the hydraulic control valve 14 via the output path 13 is formed at the upper end portion thereof. Inside the exhaust valve actuator main body 31, a first cylinder chamber 36 to which the output path 13 is connected via a connection port 37, a second cylinder chamber 39 having an inner diameter smaller than the first cylinder chamber 36, and a first cylinder chamber A hole 33 that communicates 36 with the second cylinder chamber 39 is formed.

  A sub piston 35 is slidably provided in the first cylinder chamber 36. The sub piston 35 has a main body portion 35a disposed in the first cylinder chamber 36, and a rod portion 35b extending from the lower end portion of the main body portion 35a through the hole 33 into the second cylinder chamber 39. is doing. The sub piston 35 has a communication passage 35c extending in the axial direction to the vicinity of the lower end portion of the rod portion 35b and a side branch from the lower end portion of the communication passage 35c into the second cylinder chamber 39. An open communication path 35d is formed, and the first cylinder chamber 36 and the second cylinder chamber 39 communicate with each other via the communication paths 35c and 35d.

  A main piston 38 is slidably provided in the second cylinder chamber 39. The main piston 38 has a main body portion 38a and a rod portion 38b extending from the lower end portion of the main body portion 38a. The rod portion 38b extends through the exhaust valve actuator body 31 to the outside, and the valve stem 3a of the exhaust valve 3 is connected to the tip portion thereof. As described above, the exhaust valve actuator 11 includes the main piston 38 and the sub piston 35 having an outer shape larger than that of the main piston 38. Further, on the lower surface side of the sub piston 35, a throttle hole 31 a penetrating to the outside is provided in the inner peripheral surface 32 of the first cylinder chamber 36. When hydraulic oil is supplied to the exhaust valve actuator 11, the operating speed of the sub piston 35 is controlled by the throttle hole 31a. Also on the inner peripheral surface 34 of the second cylinder chamber 39, a throttle hole 31 b for controlling the operating speed of the main piston 38 is provided on the lower surface side of the main piston 38.

Next, the configuration of the intake valve actuator 12 will be described with reference to FIG.
The intake valve actuator 12 includes an intake valve actuator main body 41, and a third cylinder including therein a small-diameter inner peripheral portion 42 and a large-diameter inner peripheral portion 43 having an inner diameter larger than that of the small-diameter inner peripheral portion 42. A chamber 43a is formed. A connection port 45 that is connected to the output port 68 of the hydraulic control valve 14 via the output path 13 is formed in the small diameter inner peripheral portion 42. An intake valve side piston 44 is slidably provided in the third cylinder chamber 43a. The intake valve side piston 44 includes an upper piston portion 44a disposed in the small-diameter inner peripheral portion 42, a lower piston portion 44b disposed in the large-diameter inner peripheral portion 43, and a rod portion extending from the lower end portion of the lower piston portion 44b. 44c. The rod portion 44c extends through the intake valve actuator body 41 to the outside, and a valve stem 6a of the intake valve 6 is connected to a tip portion thereof.

  The upper piston portion 44a of the intake valve side piston 44 has a communication passage 46 extending in the axial direction to the vicinity of the lower end portion of the upper piston portion 44a, and a large branching sideways from the lower end portion of the communication passage 46. A communication passage 48 penetrating into the inner diameter peripheral portion 43 is formed. In addition, a check valve 49 that includes a spherical member 49 a and a spring 49 b and that allows only hydraulic fluid to flow from the small-diameter inner peripheral portion 42 to the large-diameter inner peripheral portion 43 is provided at the lower end portion of the communication passage 46. ing. Further, on the upper side of the check valve 49, that is, on the side opened to the small-diameter inner peripheral portion 42, a branch hole 47 that branches from the communication passage 46 and opens to the outer peripheral surface of the upper piston portion 44a is formed. . The branch hole 47 is accommodated in the small-diameter inner peripheral portion 42 when the intake valve 6 is closed. Further, when the intake valve side piston 44 moves and the intake valve 6 opens, the branch hole 47 is arranged in the large-diameter inner peripheral portion 43.

Next, the operation of the valve gear for the internal combustion engine according to Embodiment 1 of the present invention will be described.
First, the operation | movement at the time of closing the intake valve 6 and the exhaust valve 3 is demonstrated using FIGS.
As shown in FIG. 5, when energization of an electromagnetic solenoid (not shown) of the hydraulic control valve 14 is interrupted, the spool valve 53 moves in the direction indicated by the arrow A in FIG. The pressure supply port 56 is opened. When the pilot pressure supply port 56 is opened, high-pressure hydraulic fluid flows into the third storage chamber 55 from the hydraulic fluid supply path 15. The hydraulic oil in the third storage chamber 55 is supplied into the first storage chamber 64 through the communication hole 60, and the seat valve 62 is moved to the arrow in FIG. 5 by the pressure of the hydraulic oil and the spring force of the seat valve spring 63. As shown by B, it moves downward and closes the opening 71.

  Since the seat valve 62 closes the opening 71 and connects the upper annular groove 61a and the lower annular groove 61b, the output port 68 and the discharge port 65 include an annular groove 67, a connection port 69, a connection path 82, and a connection port. 66, the lower annular groove 61b and the upper annular groove 61a are communicated with each other in this order. On the other hand, high-pressure hydraulic fluid is also supplied into the second storage chamber 75 provided with the gate valve 73 via the hydraulic fluid supply path 15 and the supply port 76. The hydraulic oil on the supply port 76 side in the second storage chamber 75 opens the check valve 77 of the gate valve 73 and flows into the opening 71, and stores high-pressure hydraulic oil in the opening 71.

  Here, the hydraulic control chamber 79 partitioned between the gate valve 73 and the second storage chamber 75 is in a state where the seat valve 62 communicates with the discharge port 65 by closing the opening portion 71. The internal pressure is released. That is, in a state where the pressure in the hydraulic control chamber 79 is high, the load acting to move the gate valve 73 upward is eliminated due to the difference in pressure receiving area between the large diameter portion 73c and the small diameter portion 73d. It becomes. Accordingly, the gate valve 73 moves downward as shown by an arrow C in FIG. 5 against the spring force of the gate valve spring 74 and the pressure on the supply port 76 side in the second storage chamber 75, and opens. A predetermined amount of hydraulic fluid having a predetermined pressure is stored in the space on the part 71 side.

  When the hydraulic control valve 14 is actuated as described above, the pressure in the exhaust valve actuator 11 is also released, so that the exhaust valve 3 is closed by the spring force of the exhaust valve spring 5 as shown by the arrow D in FIG. The Further, when the exhaust valve 3 is closed, the exhaust valve 3 pushes up the sub piston 35 and the main piston 38 in the exhaust valve actuator 11, but the sub piston 35 has an outer diameter larger than that of the main piston 38. Motion is buffered before sitting. In this way, the hydraulic oil in the exhaust valve actuator 11 is returned to the hydraulic control valve 14.

  The operation of the hydraulic control valve 14 when closing the intake valve 6 is the same as that of the exhaust valve 3, and the output port 68 and the discharge port 65 are communicated. When the pressure in the intake valve actuator 12 is released, the intake valve 6 is closed by the spring force of the intake valve spring 8 as shown by an arrow E in FIG. Here, the intake valve side piston 44 of the intake valve actuator 12 is disposed in the communication passage 46 provided with the check valve 49 and in the large-diameter inner peripheral portion 43 when the intake valve 6 is open. Branch holes 47 are provided. Therefore, the intake valve 6 is closed until the branch hole 47 is accommodated in the small-diameter inner peripheral portion 42 and closed. When the branch hole 47 is closed, the check valve 49 is also closed and the intake valve 6 is not seated. Buffer shocks.

Next, the operation when the intake valve 6 and the exhaust valve 3 are opened will be described with reference to FIGS.
As shown in FIG. 8, when an electromagnetic solenoid (not shown) of the hydraulic control valve 14 is energized, the spool valve 53 moves in the direction indicated by the arrow F in FIG. 8 against the spring force of the spool valve spring 54. The pilot pressure discharge port 58 is opened. When the pilot pressure discharge port 58 is opened, the pressure in the first storage chamber 64 is released through the communication hole 60, the third storage chamber 55, and the pilot pressure discharge port 58. When the pressure in the first storage chamber 64 is released, the seat valve 62 moves upward as indicated by an arrow G in FIG. 8 due to the pressure of the high-pressure hydraulic oil stored in the opening 71. To open the opening 71. Here, when the seat valve 62 moves upward, the lower annular groove 61b is blocked, so that the communication between the output port 68 and the discharge port 65 is blocked.

  When the opening 71 is opened and the communication between the output port 68 and the discharge port 65 is blocked, the high-pressure hydraulic oil stored in the opening 71 is exhausted through the output port 68 and the output path 13. It is sent to the valve actuator 11 or the intake valve actuator 12. When the opening 71 is opened, the opening 71 and the hydraulic control chamber 79 defined between the gate valve 73 and the second storage chamber 75 communicate with each other. Also flows into the chamber 79. When the pressure in the hydraulic control chamber 79 is increased in this way, a load that pushes the gate valve 73 upward acts due to a difference in pressure receiving area between the large diameter portion 73c and the small diameter portion 73d of the gate valve 73. The valve 73 moves upward as indicated by an arrow H in FIG. 8 by the spring force of the gate valve spring 74 and reliably supplies the stored high-pressure hydraulic oil to the intake valve actuator 12 or the exhaust valve actuator 11. .

  When the hydraulic control valve operates as described above, hydraulic oil is supplied from the hydraulic control valve 14 to the exhaust valve actuator 11. The hydraulic oil sent to the exhaust valve actuator 11 first flows into the first cylinder chamber 36 and slightly moves the sub piston 35 having an outer shape larger than that of the main piston 38. Here, although the combustion chamber immediately after the combustion stroke is in a high pressure state due to the generated exhaust pressure, the pressure in the combustion chamber is released by slightly opening the exhaust valve 3 by the sub piston 35. Next, the hydraulic oil that has flowed into the second cylinder chamber 39 through the communication passages 35c and 35d moves the main piston 38, but the pressure in the combustion chamber is at the time when the auxiliary piston 35 opens the exhaust valve 3. Therefore, the main piston 38 can be moved with a small hydraulic pressure, and the exhaust valve 3 can be fully opened.

  On the other hand, on the intake valve actuator 12 side, the hydraulic oil that has flowed into the small-diameter inner peripheral portion 42 opens the check valve 49 of the intake valve-side piston 44 and flows into the large-diameter inner peripheral portion 43. Since the pressure in the combustion chamber when opening the intake valve 6 is not in a high pressure state, the intake valve 6 can be opened by the intake valve side piston 44. When the intake valve side piston 44 moves downward and the branch hole 47 is disposed in the large-diameter inner peripheral portion 43, the hydraulic oil passes from the small-diameter inner peripheral portion 42 through the branch hole 47. 43 flows in.

  As described above, in the valve operating apparatus 1 for the internal combustion engine, the hydraulic control valve 14 is configured as described above. Therefore, when the seat valve 62 closes the opening 71, the output port 68 and the discharge port 65 are communicated. The hydraulic oil in the intake valve actuator 12 or the exhaust valve actuator 11 is returned to the hydraulic control valve 14, and the intake valve 6 and the exhaust valve 3 can be closed. In addition, hydraulic fluid that has flowed through the through hole 73a of the gate valve 73 flows into the opening 71 that is closed by the seat valve 62. When the opening 71 is closed, the hydraulic control chamber 79 and the discharge port 65 are in communication with each other, so the hydraulic control chamber 79 is opened, whereby the gate valve 73 moves to the supply port 76 side, and the opening A predetermined amount of hydraulic oil having a predetermined hydraulic pressure is stored on the opening 71 side in the 71 and the second storage chamber 75.

  On the other hand, when the opening 71 is opened by the seat valve 62, the opening 71 communicates with the output port 68, so high-pressure hydraulic oil is supplied into the intake valve actuator 12 and the exhaust valve actuator 11, and the intake valve 6 and The exhaust valve 3 is opened. In addition, when the opening 71 is opened, high-pressure hydraulic oil flows into the hydraulic control chamber 79, so that the gate valve 73 moves to the side of the opening 71 by the spring force of the gate valve spring 74, and a predetermined amount The hydraulic oil is reliably supplied to the intake valve actuator 12 or the exhaust valve actuator 11.

  The opening and closing of the opening 71 by the seat valve 62 can be controlled by an electric signal based on an angle signal from the crankshaft, for example, using hydraulic pressure, so that optimum control according to the operating condition of the internal combustion engine is possible. become. Further, in order to open and close the intake valve 6 and the exhaust valve 3, it is not necessary to use cams, tappets, push rods and rocker arms, and it is not necessary to extract driving force from the crankshaft using gears. Can be simplified. Therefore, in the valve operating apparatus 1 of the internal combustion engine, the intake valve 6 and the exhaust valve 3 are operated at the optimal opening / closing timing and opening period to reduce fuel consumption and clean the exhaust gas, and simplify the structure to reduce noise. It is possible to reduce manufacturing costs and maintenance costs.

  In addition, since the third storage chamber 55 is formed in the control valve body 51 of the hydraulic control valve 14 and the spool valve 53 is provided therein, the pilot valve is moved by moving the spool valve 53 in the third storage chamber 55. The supply port 56 and the pilot pressure discharge port 58 can be selectively opened and closed. Therefore, the operation of the entire hydraulic control valve 14 can be controlled only by operating the spool valve 53 using, for example, an electromagnetic solenoid. Further, since the spool valve 53 is accommodated in the control valve main body 51, the operations of the intake valve 6 and the exhaust valve 3 can be controlled without complicating the structure.

  In the exhaust valve actuator 11, a sub piston 35 having an outer diameter larger than that of the main piston 38 is provided in the first cylinder chamber 36 connected to the output port 68 of the hydraulic control valve 14, and communication passages 35 c and 35 d of the sub piston 35 are provided. Since the first cylinder chamber 36 and the second cylinder chamber 39 are communicated with each other through the first, the exhaust valve 3 can be slightly opened by the large force of the auxiliary piston 35 against the high pressure in the combustion chamber. After the exhaust valve 3 is opened and the high pressure in the combustion chamber is released, the main piston 38 is moved by the small flow rate of hydraulic oil flowing into the second cylinder chamber 39 through the communication passages 35c and 35d, and the exhaust valve 3 Can be fully opened. Further, when the exhaust valve 3 is closed, the hydraulic oil is compressed in the first cylinder chamber 36 to cause a braking action, so that an impact when the exhaust valve 3 is seated can be buffered.

  Further, in the intake valve actuator 12, since the communication passages 46, 48 in which the check valve 49 is provided in the intake valve side piston 44 and the branch hole 47 are formed, when hydraulic oil is supplied from the hydraulic control valve 14, The hydraulic oil flows into the large-diameter inner peripheral portion 43 through the communication passages 46 and 48 and the check valve 49, and the intake valve side piston 44 is moved by the hydraulic pressure to open the intake valve 6. On the other hand, when the intake valve 6 is closed, the hydraulic oil in the large-diameter inner peripheral portion 43 is discharged until the branch hole 47 moves into the small-diameter inner peripheral portion 42. Further, when the branch hole 47 moves into the small-diameter inner peripheral portion 42, the hydraulic oil in the third cylinder chamber 43a is compressed to produce a braking action, so that the impact when the intake valve 6 is seated can be buffered. it can.

1 is a schematic diagram showing a valve gear for an internal combustion engine according to Embodiment 1 of the present invention. 1 is a cross-sectional side view showing an electromagnetic solenoid type hydraulic control valve in a valve operating apparatus for an internal combustion engine according to Embodiment 1. FIG. FIG. 3 is a cross-sectional side view showing an exhaust valve actuator in the valve gear for the internal combustion engine according to the first embodiment. FIG. 3 is a cross-sectional side view showing the intake valve actuator in the valve operating apparatus for the internal combustion engine according to the first embodiment. FIG. 3 is a cross-sectional side view for explaining the operation of the electromagnetic solenoid hydraulic control valve in the valve operating apparatus for the internal combustion engine according to the first embodiment. FIG. 3 is a schematic diagram for explaining the operation on the exhaust valve side in the valve gear for the internal combustion engine according to the first embodiment. FIG. 3 is a schematic diagram for explaining the operation on the intake valve side in the valve gear for the internal combustion engine according to the first embodiment. FIG. 3 is a cross-sectional side view for explaining the operation of the electromagnetic solenoid hydraulic control valve in the valve operating apparatus for the internal combustion engine according to the first embodiment. FIG. 3 is a schematic diagram for explaining the operation on the exhaust valve side in the valve gear for the internal combustion engine according to the first embodiment. FIG. 3 is a schematic diagram for explaining the operation on the intake valve side in the valve gear for the internal combustion engine according to the first embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Valve operating apparatus of an internal combustion engine, 3 Exhaust valve, 6 Intake valve, 11 Exhaust valve actuator, 12 Intake valve actuator, 14 Hydraulic control valve, 18 Tank, 19 Electric motor (hydraulic power source), 20 Pump (hydraulic power source), 31 Exhaust valve actuator main body, 35 sub piston, 35a sub piston main body, 35b sub piston rod, 35c, 35d sub piston communication passage, 36 first cylinder chamber, 39 second cylinder chamber, 38 main piston, 41 intake Valve actuator body, 42 Small diameter inner periphery, 43 Large diameter inner periphery, 43a Third cylinder chamber, 44 Intake valve side piston, 44a Upper piston portion, 44b Lower piston portion, 46, 48 Communication path, 47 Branch hole, 49 Check valve, 51 Control valve body, 53 Spool valve, 55 Third storage chamber, 56 Pilot pressure supply port 58 pilot pressure discharge port, 62 seat valve, 64 first storage chamber, 65 discharge port, 68 output port, 71 opening, 73 gate valve, 73a through hole, 73b intermediate portion, 73c large diameter portion, 73d small diameter portion, 74 Gate valve spring, 75 Second storage chamber, 76 Supply port, 77 Check valve, 79 Hydraulic control chamber.

Claims (4)

A hydraulic pressure source that boosts and discharges hydraulic oil in the tank;
An intake valve actuator that operates with the hydraulic oil supplied from the hydraulic power source to open and close an intake valve of an internal combustion engine and an exhaust valve actuator that opens and closes an exhaust valve;
A hydraulic control valve provided between the hydraulic source and the intake valve actuator and between the hydraulic source and the exhaust valve actuator,
Each of the hydraulic control valves is
(A) a first storage chamber in which an output port connected to the intake valve actuator or the exhaust valve actuator and a discharge port connected to the tank are formed;
A control valve main body having a second storage chamber formed therein and communicating with an end of the first storage chamber through an opening, and in which a supply port connected to the hydraulic pressure source is formed;
(B) a seat valve slidably provided in the first storage chamber,
Opening and closing the opening to switch communication and blocking between the output port and the opening,
When the opening is opened, the output port and the discharge port are shut off,
A seat valve that communicates the output port and the discharge port when the opening is closed;
(C) a slidably provided valve in the second storage chamber, and partitions the second storage chamber into the opening side and the supply port side;
And (d) a gate valve spring that biases the gate valve toward the opening,
The gate valve is
A large diameter portion arranged on the opening side, an outer diameter smaller than the large diameter portion, a small diameter portion arranged on the supply port side, and formed between the large diameter portion and the small diameter portion. And having an intermediate portion for partitioning the hydraulic control chamber between the second storage chamber and
A through hole penetrating from the supply port side in the second storage chamber to the opening side in the second storage chamber; and provided in the through hole; and from the supply port side in the second storage chamber to the second storage chamber A check valve that allows only the flow of the hydraulic oil to the opening side in the room,
The hydraulic control chamber is
When the seat valve opens the opening, connected to the opening;
A valve operating apparatus for an internal combustion engine, wherein the valve is connected to the discharge port when the seat valve closes the opening. The control valve main body communicates with an end of the first storage chamber opposite to the second storage chamber, and is connected to the hydraulic pressure source and a pilot pressure supply port connected to the tank. A third storage chamber in which a pressure discharge port is formed;
A spool valve that selectively opens and closes the pilot pressure supply port and the pilot pressure discharge port and controls the opening and closing of the opening by the seat valve is slidably provided in the third storage chamber. Item 8. A valve operating apparatus for an internal combustion engine according to Item 1. The exhaust valve actuator is
An exhaust valve actuator body having a first cylinder chamber and a second cylinder chamber connected to the output port of the hydraulic control valve;
A secondary piston slidably provided in the first cylinder chamber;
A slidably provided in the second cylinder chamber, and a main piston connected to the exhaust valve;
The sub-piston includes a main body that slides in the first cylinder chamber, a rod that is fixed to the main body and extends into the second cylinder chamber, the first cylinder chamber, and the second cylinder chamber. The internal combustion engine valve operating device according to claim 1 or 2, wherein the main body portion has a larger outer diameter than the main piston. The intake valve actuator is
An intake valve actuator body having therein a third cylinder chamber comprising a small-diameter inner peripheral portion connected to the output port of the hydraulic control valve and a large-diameter inner peripheral portion having an inner diameter larger than the small-diameter inner peripheral portion;
It has an upper piston part arranged in the small diameter inner peripheral part and a lower piston part arranged in the large diameter inner peripheral part, and is slidably provided in the third cylinder chamber and connected to the intake valve An intake valve side piston to be
The intake valve side piston is
A communication passage penetrating from the small diameter inner peripheral portion to the large diameter inner peripheral portion;
A check valve that is provided in the communication path and allows only the flow of the hydraulic oil from the small-diameter inner peripheral portion to the large-diameter inner peripheral portion;
4. The device according to claim 1, further comprising: a branch hole that branches from the communication path and opens to an outer peripheral surface of the upper piston portion, and moves into the small-diameter inner peripheral portion when the intake valve is closed. The valve operating apparatus for an internal combustion engine according to 1.

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