KR101657752B1 - An arrangement and a method of operating a gas exchange valve of an internal combustion engine, a cylinder head and a method of upgrading an internal combustion engine - Google Patents

Abstract

The present invention relates to an apparatus and a method for operating a gas exchange valve of an internal combustion engine. The present invention is characterized in that at the time of opening the gas exchange valve 102, one or more open pressure chambers 40, 42, 44 are connected to the pressure medium supply section 70 to regulate the force for opening the gas exchange valve 102 By connecting the open pressure chambers 40, 42, 44 to the pressure outlet 60, by selecting to connect and when closing the gas exchange valve 102, the control means 80, 82 , 84; 90, 92, 94) to operate the gas exchange valve 102 of the internal combustion engine by means of a pressure medium actuator. The present invention also relates to a novel method for improving a new cylinder head and an internal combustion engine.

Description

FIELD OF THE INVENTION [0001] The present invention relates to an apparatus and method for operating a gas exchange valve of an internal combustion engine, a method for upgrading a cylinder head, and an internal combustion engine, and a method for upgrading an internal combustion engine. INTERNAL COMBUSTION ENGINE}

The present invention relates to an apparatus and a method for operating a gas exchange valve of an internal combustion engine. The present invention also relates to a novel method for upgrading a new cylinder head and an internal combustion engine.

Conventionally, a gas exchange valve of a cylinder in an internal combustion or piston engine is controlled by a camshaft, which on the one hand is connected to the crankshaft of the engine by a gear or a chain or belt so as to rotate with the crankshaft On the other hand, is mechanically connected to the valve by push rod and rockers, by a simple rocker, or by direct contact between the cam of the camshaft and the valve stem. Thus, all the valves in the cylinder row are controlled by the same camshaft, or, alternatively, both the inlet and outlet valves have their respective camshafts. During operation, the use of a valve mechanism driven by the camshaft provides only a very limited possibility of changing the valve timing, so valve timing is always a compromise.

Due to increasingly stringent emission regulations, engine manufacturers are obliged to reduce the emissions of the engine. At the same time, the goal is to keep engine performance unchanged or even improve engine performance. This is only possible through accurate real-time adjustment and control of the engine. Control of the fuel supply is significantly improved with the introduction of electrically controlled fuel injection. In addition, the control of the gas exchange valve should be improved in order to make the engine as efficient as possible at all engine speeds and engine loads. Each control of the gas exchange valve improves the efficiency, the heat consumption rate and the output of the engine and reduces the exhaust gas. This is not possible with a valve mechanism driven by a camshaft. In order to overcome the above-mentioned problems, a hydraulic actuator has been proposed for operating the engine valve without direct mechanical contact of the camshaft.

When a gas exchange valve (GEV) is operated with a hydraulic actuator, the actuator needs to be dimensioned against the imaginable maximum opening force of the gas exchange valve under certain operating conditions. The opening force is the result of the pressure of the hydraulic system connected to the actuator and the effective surface area of the actuator. The oil pressure consumed to open the gas exchange valve is the result of the pressure and volume flow of the hydraulic system. The large effective surface area of the actuator results in a high volumetric flow and thus high power consumption in the system. That is, the power consumption of the hydraulic actuator is constant regardless of the force actually required to open the gas exchange valve.

EP-B1-1 403 473 discloses a hydraulic valve actuation system. The EP patent document discloses a hydraulic actuator used for operating a gas exchange valve of an internal combustion engine. The hydraulic actuator has a body provided with an internal cavity for receiving the piston. The piston has its axial end disposed in communication with the valve stem. The piston has the smallest diameter of the top section (at the end opposite the end communicating with the valve stem), the center section having the largest diameter, the bottom section having a diameter greater than the diameter of the top section, And has three coaxial cylindrical sections. The piston section forms several coaxial chambers with the internal cavity of the actuator body. There is a first annular chamber on the top piston section, a second annular chamber on the central section of the piston, and a third annular chamber below the central section of the piston. Sectional area of the effective surface of the chamber is such that the surface area of the first chamber is the smallest and the surface area of the second annular chamber is the largest and the surface area of the third annular chamber is smaller than the surface area of the second annular chamber, To be larger than the surface area of the substrate. The chamber is connected to the high-pressure fluid supply and to the low-pressure fluid supply by a pressure conduit and valve means except for a third annular chamber in constant flow communication with the high-pressure fluid supply. The operation of the hydraulic actuator is controlled by a control valve that allows fluid flow forced from the high-pressure fluid supply to the second annular chamber in its first position. The high pressure fluid acting on the largest surface area is influenced by opening the valve against the forces resulting from the valve spring, the high pressure fluid acting on the surface area of the third annular chamber, the gas pressure of the cylinder of the internal combustion engine, It goes crazy. In its second position, the control valve permits communication of the second annular chamber with the low-pressure fluid supply, so that the high pressure conventionally used in the third annular chamber, which acts on the second largest surface area of the piston, Help turn over. In addition to the only basic operation of the valve, the upper end of the piston, i. E. The first chamber, is provided with means for dampening the upward movement of the piston in order to lower the speed at which the valve is closed, Do not hit the seat. For this cushioning purpose, the first chamber is disposed in flow communication with the high pressure and low pressure fluid supply through a specific valve arrangement. Thus, the second chamber does not engage in the opening of the gas exchange valve, only delaying the final closing of the gas exchange valve.

The EP patent document also discloses another piston structure for a hydraulic actuator. In a second embodiment, the central section of the piston is formed of two coaxial parts that are slidable relative to each other. That is, the exterior, i. E. The second part of the piston, is an annular sleeve disposed about the first member of the piston used to actuate the valve stem. In the first position, the annular piston part is supported on the shoulder of the first piston part (when the gas exchange valve of the internal combustion engine is closed), and in the second position, the annular part (when the gas exchange valve is closed) And is supported by the shoulder portion of the inner wall. When the second annular chamber having the largest cross-sectional area, that is, the chamber on the two piston members, is pressed by the high-pressure fluid, the two piston parts move together, that is, the annular piston part supported on the shoulder of the first piston part Actuate the actuator to assist in moving the piston down and unseating the gas exchange valve. The annular piston part is stopped and brought into contact with the shoulder of the chamber inner wall after a certain length of downward movement which causes the first part of the piston to continue to move down but to have considerably less force due to the smaller effective area.

That is, the hydraulic actuators of the prior art described above attempt to reduce the energy consumption associated with operating the gas exchange valve. However, the resulting savings represent only a small improvement over earlier prior art hydraulic actuator systems. In fact, the hydraulic actuators of the above-mentioned EP patent document do so in consideration of the pressure reduction in the combustion chamber immediately after the gas exchange valve is separated, that is, immediately after lifting the valve plate off the seat surface. That is, immediately after separating the gas exchange valve, the pressure in the combustion chamber is released, whereby the cylinder pressure no longer interferes with or at least significantly lessens the opening of the gas exchange valve, and the valve opening continues with less force . Thus, the EP patent teaches a hydraulic actuator structure that begins to separate gas exchange valves at a constant force, which is the maximum imaginable force required to open, i.e. open the gas exchange valve. After disconnecting the gas exchange valve, the opening force decreases to a fixed value. The result is that the pressure fluid (and power) consumption is somewhat reduced, but that the hydraulic actuator considers two different open states of the gas exchange valve, i.e., the split state and the final open state. However, the prior art hydraulic actuators can not take into account the various accelerations of the gas exchange valve due to various pressure conditions or various engine speeds of the combustion chamber of the internal combustion engine due to various cylinder loads.

The basis of the present invention is that the force required to operate the gas exchange valve of the internal combustion engine is not constant. The force required to separate and open the gas exchange valve depends on several factors. The first factor is acceleration of the valve, which is proportional to the engine speed and proportional to the mass of gas exchange valves and pistons of the hydraulic actuator. The second factor is the pressure difference across the valve plate, which is effective until the end of the separation state. The pressure differential depends on the engine operating conditions, i.e., engine load and crank angle. The third factor is the force resulting from the spring (if used) of the gas exchange valve. And the fourth factor is the fluid pressure (if any) of the actuator acting on the piston motion (the third annular chamber of EP-B1-1 403 473).

A first object of the present invention is to overcome some weaknesses, disadvantages and problems of the prior art hydraulic actuators used to open the gas exchange valve (s) of the internal combustion engine.

A second object of the present invention is to provide a method and system for controlling the power consumption of a hydraulic actuator by adjusting the force used to open the gas exchange valve to meet the requirement that the pressure difference across the valve plate is set for the force required to open the gas exchange valve .

A third object of the present invention is to enable the operation of the hydraulic actuator and the flow rate of the hydraulic actuator to be adjusted to meet the requirement that the speed of the engine is set at the valve opening / closing speed.

A fourth object of the present invention is to provide a structurally simple hydraulic actuator, i. E. An actuator with a minimum number of parts, wherein the parts have very little surface to be machined and sealed, whereby the gas exchange valve (s) The actuators resulting from opening the actuators are cheap, reliable, and highly adjustable.

A fifth object of the present invention is to improve the reliability of the system. When several control valves are used, one of them fails the system, but only a part of the system performance is lost. With intelligent control, the system can identify failed parts and can be readjusted to failure mode.

A seventh object of the present invention is to provide a simple and energy efficient means for repairing and upgrading / modernizing the state-of-the-art internal combustion engine with mechanical means for communicating with the camshaft and the camshaft for operating the gas exchange valve.

An eighth object of the present invention is to provide a novel cylinder head for modernizing an internal combustion engine to meet today's needs for energy efficiency and emission control.

A ninth object of the present invention is to provide a pressure medium actuator for operating a gas exchange valve of an internal combustion engine. That is, the actuator may be pneumatic as well as hydraulic.

At least the object of the invention is fulfilled by an apparatus for operating a gas exchange valve of an internal combustion engine, the apparatus comprising: a pressure medium supply, a pressure medium outlet, a body including an inner cavity with a cylindrical wall portion having a different diameter, A pressure medium actuator comprising a single piston movably disposed within an inner cavity, the piston having a shape corresponding to the shape of the inner cavity, the pressure medium actuator further comprising an open pressure chamber, the piston being disposed in the chamber And a control means for switching the connection of the open pressure chamber between the pressure medium supply and the pressure, wherein the apparatus comprises at least one additional opening pressure At least one additional effective surface mounted to the piston and at least one Includes additional control means, and the control means is arranged to connect the at least one opening pressure chamber in order to control the force for opening the gas exchange valve in the pressure medium supply.

At least the object of the present invention is achieved by a method for operating a gas exchange valve of an internal combustion engine by means of the apparatus described above,

- when the gas exchange valve is open,

By selecting one or more open pressure chambers connected to the pressure medium supply to regulate the force for opening the gas exchange valve,

- when the gas exchange valve is closed,

By connecting the open-pressure chamber to the pressure outlet,

One or more engine characteristics.

At least the object of the invention is fulfilled by a cylinder head of an internal combustion engine, the cylinder head comprising means for operating at least two gas exchange valves and a gas exchange valve, at least one means for operating the gas exchange valve One or more device claims.

At least the object of the invention is met by a method for upgrading an internal combustion engine having a cylinder head having at least one gas exchange valve and mechanical gas exchange valve actuating means, As shown in FIG.

The present invention, at least in part, solves many of the above-mentioned problems, some of which are described below. The pressure medium actuator of the present invention comprises:

- Can be used to operate gas exchange valves of internal combustion engines. The internal combustion engine may be a two or four-stroke engine.

- Reduce volumetric flow in the system, allowing cost savings through lower energy consumption.

- Only the failure of a single control valve eliminates the force combination parts, thereby increasing the reliability of the valve operating system.

- Allows better control of gas exchange valve speed.

- better control of the organism, resulting in reduced emissions.

- Old cylinder heads can be used to replace camshafts, push rods, and rocker mechanisms of the prior art so that they can be easily modernized to meet today's needs.

- have a simple construction, and therefore are inexpensive to manufacture and less prone to failure or deterioration.

It should be understood, however, that the advantages described are merely optional, and that the number of advantages thereby depends on the manner in which the present invention is implemented.

In the following, the invention is explained in more detail with reference to the accompanying drawings.

1 shows an axial cross-sectional view of a pressure medium actuator device with a gas exchange valve according to an embodiment of the invention in an open state of the gas exchange valve.
Figure 2 shows an axial cross-sectional view of the pressure medium actuator arrangement of Figure 1 in the closed state of the gas exchange valve.
Figure 3 shows an axial cross-sectional view of the pressure medium actuator device in another open state of the gas exchange valve.
4 shows an axial cross-sectional view of a pressure medium actuator according to another embodiment of the present invention. And,
Figure 5 schematically illustrates another exemplary option for a control valve used to control the operation of the pressure medium actuator of the present invention.

1 shows an axial cross-sectional view of a pressure medium actuator 10. Fig. The actuator 10 includes a body 12 that includes an interior cavity that extends from the vicinity of the end 14 of the body to the opposite end 16 of the body 10. The end portion 16 of the body is mounted with a cover 18, preferably provided with a central opening 20. The inner cavity is formed by a number of cylindrical wall portions 22, 24 and 26 such that the diameter of the wall portions increases toward the end of the body with the cover 18. The pressure medium actuator 10 has a single piston 30 and the shape of the single piston substantially corresponds to the shape of the internal cavity of the body 12. [ That is, in this embodiment, a single piston is formed of four cylindrical sections 32, 34, 36 and 38 arranged axially one above the other. The top section 32 of the piston 30 has a diameter corresponding to the diameter of the wall portion 22, but there remains a sufficient working clearance therebetween. In a similar manner the second section 34 of the piston 30 has a diameter corresponding to the diameter of the wall section 24 and the third section 36 of the piston corresponds to the diameter of the third wall section 26 . The fourth section 38 of the piston 30 has a diameter corresponding to the diameter of the central opening 20 in the cover 18.

The inner cavity of the body 12 of the pressure medium actuator and the piston 30 form the pressure chambers 40, 42, 44 and 46. The chamber 40 is defined by the wall portion 22, the end face of the inner cavity, and the end face 48 of the first section 32 of the piston 30. The chamber 42 includes a wall portion 24, a cylindrical side of the first section 32 of the piston 30, an annular end face 50 of the second section 34 of the piston 30, 1 wall portion 22 and the second wall portion 24, respectively. The chamber 44 includes a wall portion 26, a cylindrical side of the second section 34 of the piston 30, an annular end face 52 of the third section 36 of the piston 30, Is defined by the shoulder surface between the wall portion 24 and the third wall portion 26. The chamber 46 includes a wall portion 26, a cylindrical side of the fourth section 38 of the piston 30, a lower annular end surface 54 of the third section 34 of the piston 30, Is defined by the surface of the opposing cover (18). The effective surface which affects the movement of the valve stem 100 and the piston 30 disposed in communication with the piston 30 is therefore defined by the end face 48 of the pressure chamber 40, The annular end surface 52 of the pressure chamber 44, and the annular end surface 54 of the pressure chamber 46. In this embodiment, Based on their operation, the pressure chambers 40, 42 and 44 may be referred to as an open pressure chamber, and the pressure chamber 46 may be referred to as a closed pressure chamber. In a similar manner, the effective surfaces 48, 50, and 52 may be referred to as an open surface, and the effective surface 54 may be referred to as a closed surface.

A preferred but non-essential feature of the present invention is that the area of the effective surface 48 is 2 ^* A, the area of the effective surface 50 is 2 ^* A, and the area of the effective surface 52 is 4 ^* The area is an exponential. The purpose of arranging the areas to form this geometric series will be described in more detail below.

The pressure medium actuator body (12) and the piston (30) form a first portion of the pressure medium valve actuation device. The second portion of the actuating device includes a tank 61, a pressure medium supply 70, a first control valve 80, 82, 84 and 86, conduits 72, 74, 76 and 78 (when the hydraulic actuator is a point) , Second control valves 90, 92, 94 and 96 and conduits 62, 64, 66 and 68, respectively. The conduits 72-78 connect the pressure medium supply to the pressure chambers 40-46 through the first control valves 80-86. The pressure chambers 40 to 46 are connected to the tank 61 by the second control valves 90, 92, 94 and 96, the conduits 62 to 68 and the pressure outlet 60. Thus, each pressure chamber has one first control valve and one second control valve to control the operation of the chamber. The control valves 80 to 86 and 90 to 96 are preferably solenoid valves or control units CU such that the control unit CU can independently open and close the respective valves based on inputs from the engine control unit. ) That are connected to the < / RTI > That is, when the control unit CU prevents the entry of current into the solenoid, the solenoid operated control valve is normally operated to close. When the electric circuit of the solenoid is closed, that is when the current enters the solenoid, the solenoid pushes the control valve against the spring to the open position. And, when the solenoid circuit is opened, the spring pushes the control valve to the closed position. Naturally, the control valve closed by the solenoid can be held, and the control valve can be opened by disconnecting the power from the solenoid circuit. In addition, two solenoids can be arranged in relation to the control valve, so that the opening and closing of the valve is effected by using a solenoid. In this specification, the first control valve 80 to 86 is shown as a valve that opens or closes the flow connection between the two-position two-way valve, i.e., the pressure chambers 40 to 46 and the pressure medium supply 70 . In a similar manner, the control valves 90-96 are shown as two-position two-way valves that open or shut off the flow connection between the pressure chambers 40-46 and the tank 61.

Fig. 1 illustrates the position of the control valve when the pressure connection, i.e. the prevailing backpressure in the combustion chamber of the cylinder of the internal combustion engine, is lowest, and therefore the force required to open the gas exchange valve 102 is at the lowest possible. A control valve 80 is connected to the pressure chamber 40 via conduit 72 to generate a pressure sufficient to open the gas exchange valve 102 in a desired manner, 70, while the operation of the pressure medium actuator is adjusted such that the other three control valves 82, 84 and 86 are closed. The control valve 90 is kept closed and thereby disconnects the connection from the pressure chamber 40 along the conduits 62 and 60 to the tank 61 so that the pressure of the pressure medium source is reduced to the effective surface of the piston The second control valve on the side of the tank 61 of the actuator is operated. The other control valves 92, 94 and 96 connect their respective pressure chambers 42, 44 and 46 to the tank 61. The high pressure medium acting on the piston surface 48 affects the opening of the gas exchange valve 102 and at the same time compresses the valve spring 104 and forces the medium of the pressure chamber 46 into the tank 61.

Figure 2 shows the operating state of the pressure medium actuator, i.e. the position of the control valve when the gas exchange valve is closed. The control valve 86 connects the pressure chamber 46 to the pressure medium supply 70 through the conduit 78 while the remaining control valves 80,82 and 84 are closed. Three of the control valves, namely the control valves 90, 92 and 94, connect their respective pressure chambers 40, 42 and 44 to the tank 61 and are connected to the pressure chambers 46 to be pressurized The second control valve is operated such that the control valve 96 is closed. High pressure media acting on the effective surface 54 of the piston moves the piston upward to close the gas exchange valve and force the medium from the pressure chambers 40, 42 and 44 into the tank 61.

It should be understood that the pressure medium actuator of the present invention may also be operated such that the piston is stopped at any desired position by using the control valve. For example, the upward movement of the piston and the upward movement of the gas exchange valve can be stopped by closing the second valves 90, 92 and 94 and also holding the first valves 80-84 closed.

Fig. 3 illustrates the position of the control valve when the operating state of this pressure medium actuator, that is, the force required to open the gas exchange valve, is significantly greater than the force in the state shown in Fig. In this specification, the control valves 80 and 84 connect their respective pressure chambers 40 and 44 to the pressure medium supply 70, while the control valves 82 and 86 are closed. Valves 90 and 94 of the second control valves are closed to cause the media pressure to act on the effective surfaces 48 and 52 (reference numbers shown in FIG. 1) in the pressure chambers 40 and 44. The control valves 92 and 96 connect their respective pressure chambers 42 and 46 to the tank 61. In this case, the force used to open the valve is 5-fold compared to the example of FIG.

3 depicts a schematic, additional, exemplary apparatus for a conduit 98 that is configured to allow the pressure chamber 42 to be actuated by both control valves 92 and < RTI ID = 0.0 > And can be emptied through the control valve 94. If the piston is assumed to be moved upward by the apparatus and only the control valves 90 and 94 are open and the control valve 92 is closed then the medium from both pressure chambers 42 and 44 will pass through the control valve 94 The speed of the actuator piston can be adjusted. Since the flow rate of the control valve 94 is limited, additional flow from the pressure chamber 42 (as compared to the general situation in which each pressure chamber is discharged through its control valve) increases the overall flow, , And the piston can move. In practice, the conduit 98 is configured such that the outflow flow from the chamber 42 can be directed to the control valve 92, the control valve 94, or both control valves 92, 94, and / May be a valve device that can be oriented to control valve 94, control valve 92, or both control valves 94, 92. Naturally, such conduit or valve arrangement may be freely disposed on the outlet side of the actuator body. 3, the media flow from any of the pressure chambers 40-44 can be directed to one, two or three second control valves 90-94, The control function of the speed of motion can be said to be maximized. For example, in the closing phase of the exhaust valve, the control valve of one of the control valves 90-94 is closed after the pressure medium from the pressure chamber is first released through their 'own' control valve, And the pressure medium is discharged through the two control valves, which makes it possible to reduce the valve closing speed. In the next step, the release of all of the pressure chambers 40-44 occurs through one control valve until one or more control valves are closed, the control valve is closed and the valve and piston motion are stopped.

That is, the present invention can sequentially adjust the force used to open the gas exchange valve. The following table describes several combinations of the forces resulting from opening the gas exchange valve and the position of the first control valve. Naturally, when opening the gas exchange valve, the control valve 86 is always closed and the control valve 96 is always kept in the tank 61 at all times (unless some damping effect is desired) Connect. Regarding the second control valves 90 to 94, the second control valves are each dependent on the position of the corresponding first control valve 80 to 84, respectively. This means that the corresponding second control valve (connected to the same pressure chamber) is in the "closed" position when the first control valve is in the "open" position, and vice versa.

Thus, this exemplary pressure medium actuator can be switched between seven different power levels according to the requirements of the gas exchange valve. The influences on the forces used, i.e. the factors with the selected combination of control valve positions, depend only on several factors, namely cylinder load, crank angle and engine speed.

Naturally, the pressure medium actuator has more or less (but at least two) pressure chambers acting on the opening of the gas exchange valve than the three pressure chambers 40, 42 and 44 shown in the previous embodiment . That is, if there are only two working pressure chambers, the number of applicable force levels is reduced to three, and if there are four working pressure chambers, the number of force levels is 15 (1 + 2 + 4 + 8) .

Thus, in theory, to meet the objectives of the present invention, the pressure medium actuated gas exchange valve may be configured such that the effective surface areas A1, A2, < RTI ID = 0.0 > ... An). ≪ / RTI >

The preferred way to select the effective surface area of the pressure chamber is the exponentiation, i.e. A, 2 ^* A, 4 ^* A ..., but other schemes can also be applied.

Figure 4 shows yet another preferred embodiment of the present invention. Here, the pressure medium actuator is provided with another pressure medium supply 70 'which is additionally connected to the system via an additional control valve 104. The pressure medium supply portion 70 'has a pressure different from the pressure of the pressure medium supply portion 70. In this specification, the first pressure medium supply part 70 is also provided with its own additional control valve 102. Both control valves 102 and 104 are connected to the control unit CU. 4 shows that the pressure medium from the supply part 70 can be transferred by the control valve 102 to the pressure chambers 40 to 46 depending on the position of the valves 80 to 86 and to the control valve 104 The pressure medium from the additional pressure medium supply part 70 'can be transferred to the pressure chambers 40 to 46 depending on the position of the valves 80 to 86. [ The purpose of adding another pressure medium supply and the purpose of disposing separate control valves for both pressure medium supply are to better control the opening force of the gas exchange valve. That is, according to the apparatus shown in Fig. 5, it is possible to switch the medium pressure supply unit having a lower pressure or higher pressure to the first control valve 80-86 and further to the pressure chamber 40-46. Naturally, it can also be further advanced by disposing an additional pressure medium supply 70 'so as to be connectable to the one or more first control valves 80-86, so that these valves (and the pressure chambers connected thereto) Can utilize the different pressures available at the supply 70 '. By adding another pressure medium supply 70 'having a pressure different from the pressure of the pressure medium supply 70, the number of different levels of force that can be achieved by the pressure medium actuator is doubled. Naturally, one or more pressure medium feeds having different pressures may also still be added to increase the adjustment options of the pressure medium actuator.

In Fig. 5, a digital flow control unit 110 is shown which may optionally be used to replace one or more control valves 80,82, 84 and 86 and one or more control valves 90-96. The flow control unit 110 includes two or more digital valves 112, 114, and 116 connected in parallel. Each valve is designed for a specific flow rate of a specific pressure difference. The flow rates of the different valves may be different. For example, the flow rate of the first valve 112 is V, the flow rate of the second valve 114 is 2 ^* V, the flow rate of the third valve is 4 ^* V, and the flow rate of the ^n- th valve is 2 ^(n-1) V. Can be changed by changing the combination of valves switched for the flow rate of the digital flow control unit 110, which results in a change in speed and moves the piston 30 (Fig. 1) and opens or closes the gas exchange valve .

With regard to the more detailed construction and operation of the pressure medium actuator, the following should be understood.

The actuator body can be formed of several parts, i.e. not only a single body part and a lower cover.

The actuator may be provided with additional equipment, such as, for example, the damping means discussed in connection with the prior art document EP-B1-1 403 473.

The actuator piston can be arranged in direct communication with the valve stem as described above, but the operation of the gas exchange valve can also be carried out, for example, by a rocker arm.

- The actuator is used to simply open the gas exchange valve as described above, but may also be arranged to close the gas exchange valve either alone or in conjunction with the valve spring. In this case, the actuator piston and the valve stem are attached to each other. Naturally, if an actuator is used to close the valve, it may be desirable to utilize the invention also in the closed state. That is, the actuator may also have several pressure chambers of different sizes for closing motion.

- The actuator can be a separate device or integrated into the cylinder head.

- A single actuator can actuate one or more gas exchange valves. The actuator may be arranged to open (and optionally close) all of the inlet or outlet, valves, of the engine cylinder.

The high pressure medium supply may be a specific fluid supply for actuating only the pressure medium actuator, but may also be part of the pressure medium circuit of the engine. For example, the fluid may be taken from the forced lubrication system of the engine.

The tank referred to in the above description relates to a hydraulic actuator device, and the preferred but non-essential place for the outlet of the pressure and the outlet oil from the actuator is the oil tank. When the actuator is pneumatic, it is clear that no tank is required, and air can be discharged from the pressure outlet directly or through some sort of filter or cleaning unit to the atmosphere.

The control valve can also be operated not only by a solenoid but also by a piezoelectric actuator, or any other applicable electric actuator which can be driven by the control system of the engine.

By means of a control valve, the operating mode disclosed in the prior art EP-B1-1 403 473 can be used by reducing the opening force after using additional force in the disengaged state of the gas exchange valve.

In the above-described embodiment, the control valve is shown as an example only. The control valve may be different from the control valve described above. For example, a two-position three-way control valve may be used to combine the first and second control valves of each pressure chamber into a single valve unit such that, for example, a single control valve performs the function of control valves 80 and 90 . In a similar manner, the rest of the control valve pairs 82 and 92, 84 and 94, and 86 and 96 may be combined.

The respective control valves, i.e. the first control valve and the second control valve, and the further control valve are preferably independently connected to the control unit such that the control unit operates a single control unit independently of any other control unit .

It should be understood that the foregoing is merely illustrative of the novel and inventive method and apparatus for operating a gas exchange valve of an internal combustion engine. The foregoing should not be understood as limiting the invention by any means, the full scope of the invention being limited only by the appended claims. It is to be understood from the foregoing description that the separate features of the present invention may be used in conjunction with other distinct features, even if such a combination is not specifically described in the description or in the drawings.

Claims (13)

An apparatus for operating a gas exchange valve of an internal combustion engine,
The apparatus comprises:
A pressure medium supply unit 70,
Pressure medium outlet 60,
- a pressure medium actuator (10) comprising a body (12) comprising an inner cavity with a cylindrical wall portion having a different diameter, and a single piston (30) movably arranged in the inner cavity, the pressure medium actuator (30) has a shape corresponding to the shape of said inner cavity, said pressure medium actuator (10) further comprising an open pressure chamber (40), said piston (30) The pressure medium actuator (10) comprising an open effective surface (48) disposed therein, and
Control means (80, 90) for switching the connection of said open pressure chamber (40) between said pressure medium supply (70) and said pressure medium outlet (60)
/ RTI >
The apparatus comprises at least one additional open pressure chamber (42, 44) provided in the pressure medium actuator (10), at least one additional effective surface (50, 52) provided in the piston (30) Further comprising control means (82, 84; 92, 94)
The control means 80,82 and 84 are adapted to connect one or more open pressure chambers 40,42,44 to the pressure medium supply 70 to control the force to open the gas exchange valve 102 Wherein the gas exchange valve is disposed in the first position. The method according to claim 1,
Characterized in that each open effective surface (48, 50, 52) of the piston (30) has an area and the areas of the open effective surfaces (48, 50, 52) Devices that operate. 3. The method of claim 2,
Characterized in that each open effective surface (48, 50, 52) of the piston (30) has an area and the areas of the open effective surfaces (48, 50, 52) are arranged in a geometric series , An apparatus for operating a gas exchange valve of an internal combustion engine. The method according to claim 1,
Characterized in that the pressure medium actuator (10) is arranged to actuate two or more gas exchange valves (102). The method according to claim 1,
Characterized in that the device comprises means arranged between the outlets of the at least two pressure chambers (40-44) for placing the flow communication from the outlet of one of the outlets to the other outlet, A device for actuating a valve. The method according to claim 1,
One or more of the first and second control valves 80-86 and 90-96 may be connected to a digital flow control unit 110 (not shown) that is capable of regulating the flow rate within and / ). ≪ / RTI > An apparatus for operating a gas exchange valve of an internal combustion engine. The method according to claim 1,
Characterized in that the device is provided with an additional pressure medium supply (70 ') connected to at least one pressure chamber (40, 42, 44, 46) by an additional control means (104) A device that actuates the exchange valve. A method of operating a gas exchange valve of an internal combustion engine by the apparatus of any one of claims 1 to 7,
The method comprising:
- when opening the gas exchange valve (102)
- selecting one or more open pressure chambers (40, 42, 44) connected to the pressure medium supply (70) to regulate the force for opening the gas exchange valve (102), and
- when closing the gas exchange valve (102)
By connecting the open pressure chambers 40, 42, 44 to the pressure outlet 60,
A method of operating a gas exchange valve of an internal combustion engine, comprising the step of operating said control means (80, 82, 84; 90, 92, 94) of said actuator (10) . 9. The method of claim 8,
The method comprising:
- when opening the gas exchange valve (102)
To open the connection between the closed pressure chamber (46) and the pressure outlet (60), to close the connection between the pressure medium supply (70) and the closed pressure chamber (46), and
- when closing the gas exchange valve (102)
Closing the connection between the closed pressure chamber (46) and the pressure outlet (60) and opening the connection between the pressure medium supply part (70) and the closed pressure chamber (46) In order to be able to enter the pressure chamber 46 for lifting the valve 30,
(86, 96) located between the pressure medium supply part (70) and the closed pressure chamber (46) and between the closed pressure chamber (46) and the pressure outlet (60) Wherein the gas exchange valve of the internal combustion engine is operated. 9. The method of claim 8,
The method may include selecting one or more open pressure chambers 40, 42, 44 based on the areas of the open effective surfaces 48, 50, 52 of the open pressure chambers 40, The method comprising the steps of: a. 9. The method of claim 8,
The method further comprises the step of applying one or more open pressure chambers (40, 42, 44) to an additional pressure medium supply (70 ') having a pressure different from the pressure of the pressure medium supply (70) And controlling the opening force of the gas exchange valve (102) by switching the gas exchange valve (102). 1. A cylinder head for an internal combustion engine,
The cylinder head comprising at least one gas exchange valve and means for actuating the gas exchange valve,
Characterized in that at least one means for actuating the gas exchange valve is the device according to any one of claims 1 to 7. A method for upgrading an internal combustion engine,
The internal combustion engine having at least one cylinder including a cylinder head having at least one gas exchange valve and mechanical gas exchange valve actuation means,
The method includes replacing the mechanical gas exchange valve actuation means with an apparatus according to any one of claims 1 to 7.

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