JP4140596B2 - Electromagnetically driven valve and internal combustion engine - Google Patents

Description

  The present invention generally relates to an electromagnetically driven valve and an internal combustion engine, and more particularly to an electromagnetically driven valve including an electromagnet constituted by a monocoil and an internal combustion engine equipped with the electromagnetically driven valve.

  Regarding a conventional electromagnetically driven valve, for example, Japanese Patent Laid-Open No. 2000-303809 discloses an electromagnetically driven valve intended to reduce the power required to open the exhaust valve (Patent Document 1). ). The electromagnetically driven valve disclosed in Patent Document 1 includes an armature shaft disposed coaxially with a valve shaft of an exhaust valve, a disk-shaped armature joined to the outer periphery of the armature shaft, and an armature and a gap above the armature. An upper coil and an upper core provided and disposed, and a lower coil and a lower core disposed with an armature and a gap provided below the armature.

By supplying a current to the upper coil and the lower coil alternately at an appropriate timing, an electromagnetic force in a direction toward the upper core and the lower core acts on the armature in order. Thereby, the armature is reciprocated, and the exhaust valve can be reciprocated between the valve closing position and the valve opening position in conjunction with the movement. The electromagnetically driven valve having such a configuration is called a translational drive type, and the mutually facing surfaces of the core and the armature remain parallel when the exhaust valve reciprocates.
JP 2000-303809 A

  When the exhaust valve that opens and closes between the combustion chamber and the exhaust port of the internal combustion engine moves from the closed position to the open position, cylinder internal pressure is generated in the combustion chamber due to the explosion process. For this reason, when the exhaust valve is composed of an electromagnetically driven valve, an attractive force that overcomes the cylinder internal pressure must be generated by the electromagnet.

  However, in the translation drive type electromagnetically driven valve disclosed in Patent Document 1 described above, the mutually facing surfaces of the core and the armature are kept parallel when the exhaust valve reciprocates. For this reason, when the exhaust valve is between the valve closing position and the valve opening position, the surface of the core and the surface of the armature are evenly separated. The electromagnetic force acting on the armature acts greatly at a position close to the core and acts small at a distant position.Therefore, in a translation drive type electromagnetically driven valve, the electromagnetic force is applied to the armature from the valve closing position to the valve opening position. It cannot be made to act greatly. Therefore, in order to generate an electromagnetic force that can overcome the cylinder internal pressure, it is necessary to supply an excessive current to the coil. In this case, there arises a problem that the power consumption of the electromagnetically driven valve increases.

  Accordingly, an object of the present invention is to solve the above-described problems, and an electromagnetically driven valve capable of obtaining a stable movement of a drive valve while suppressing an increase in power consumption and an internal combustion engine equipped with the electromagnetically driven valve are provided. Is to provide.

  An electromagnetically driven valve according to one aspect of the present invention includes a drive valve having a valve shaft, and first and second arm members that are provided at a distance from each other and reciprocate the drive valve by swinging. And an electromagnet having a monocoil and disposed between the first arm member and the second arm member. The first and second arm members have one end supported to be swingable and the other end connected to the valve shaft. The electromagnet causes an electromagnetic force to act on the first and second arm members by swinging the first and second arm members by supplying a current to the monocoil. The distance between the position where one end is swingably supported and the position where the other end is connected to the valve shaft is smaller in the first arm member than in the second arm member.

  In addition, a monocoil refers to the coil comprised from the continuous continuous line (it understands similarly about the following monocoil). When a current is supplied to the monocoil, an electromagnetic force acts on both the first and second arm members at the same time.

  According to the electromagnetically driven valve configured in this manner, when the first and second arm members are viewed as levers that swing around a position where one end is supported as a fulcrum, the position serving as the fulcrum and the other end In the first arm member having a relatively small distance from the position where is connected to the valve shaft, the electromagnetic force acting on the first arm member from the electromagnet is larger, and the force for reciprocating the drive valve ( Hereinafter, it can be applied to the valve shaft as a driving force. On the other hand, in the second arm member having a relatively large distance between the position where one end is supported and the position where the other end is connected to the valve shaft, the second arm member is moved from the valve shaft to the valve shaft. The driving force that acts is smaller than the driving force that acts on the valve shaft from the first arm member.

  The electromagnetic force acts greatly at a position close to the electromagnet and acts small at a distance. For this reason, in the present invention, the position where the driving force acting on the valve shaft from the first arm member and the driving force acting on the valve shaft from the second arm member balance the first arm member from the intermediate position. Is located relatively far from the electromagnet, and the second arm member is shifted to the side located relatively close to the electromagnet. In this case, when the electromagnetic force is applied to the first arm member to swing the first and second arm members, the time for supplying the current to the monocoil can be advanced. Here, the “intermediate position” refers to a position where the distance between the electromagnet and the first arm member is equal to the distance between the electromagnet and the second arm member.

  As a result, when an electromagnetic force is applied to the first arm member to swing the first and second arm members, larger electromagnetic force energy can be used as energy for reciprocating the drive valve. . Therefore, even when the external load acting on the drive valve fluctuates with the reciprocating motion of the drive valve, the timing at which the load increases and the timing at which the current supply to the monocoil is accelerated are matched. Thus, the drive valve can be moved stably without losing the load. Moreover, since such an effect can be obtained without supplying an excessive current to the monocoil, an increase in power consumption can be prevented.

  Preferably, the first and second arm members have a position where one end of the first arm member is supported so as to be swingable, and a position where one end of the second arm member is supported so as to be swingable. Are provided so as to extend in parallel with the direction in which the drive valve reciprocates. According to the electromagnetically driven valve configured as described above, the one ends of the first and second arm members can be provided at positions where the distances from the drive valve are equal to each other. As a result, the base member for swingably supporting the first and second arm members can be formed with a simple shape and the strength thereof can be ensured.

  Preferably, the angle at which the first arm member swings around a position where one end is supported is smaller than the angle at which the second arm member swings. According to the electromagnetically driven valve configured as described above, the electromagnetic force generated by the electromagnet can be applied to the first arm member that swings at a relatively small angle. As a result, the driving force acting on the valve shaft from the first arm member increases, so that when the electromagnetic force is applied to the first arm member and the first and second arm members are swung, a current is applied to the monocoil. The supply time can be further advanced.

  An electromagnetically driven valve according to another aspect of the present invention includes a drive valve having a valve shaft, and first and second arm members that are provided at a distance from each other and reciprocate the drive valve by swinging. An electromagnet disposed between the first arm member and the second arm member, wherein the electromagnet is made to swing the first and second arm members by applying an electromagnetic force, and the electromagnet is sandwiched between the second arm members. And a demagnetizing electromagnet provided on the opposite side. The first and second arm members have one end supported to be swingable and the other end connected to the valve shaft. The electromagnet has a monocoil, and the demagnetizing electromagnet has a coil. By supplying a current to the monocoil, a magnetic flux flowing in a predetermined direction is formed in the second arm member, and by supplying a current to the coil, a magnetic flux flowing in a direction opposite to the predetermined direction is formed in the second arm member. Is done.

  According to the electromagnetically driven valve configured in this way, the magnetic flux in the second arm member formed by supplying current to the monocoil is weakened by the magnetic flux formed by supplying current to the coil. For this reason, a relatively large electromagnetic force acts on the first arm member and a relatively small electromagnetic force acts on the second arm member by supplying the current to the monocoil and the coil. Therefore, the driving force that acts on the valve shaft from the first arm member is larger than the driving force that acts on the valve shaft from the second arm member.

  For this reason, in the present invention, the position where the driving force acting on the valve shaft from the first arm member and the driving force acting on the valve shaft from the second arm member balance the first arm member from the intermediate position. Is located relatively far from the electromagnet, and the second arm member is shifted to the side located relatively close to the electromagnet. In this case, when the electromagnetic force is applied to the first arm member to swing the first and second arm members, the time for supplying the current to the monocoil can be advanced. Can be used as energy for reciprocating the drive valve.

  Therefore, even when the external load acting on the drive valve fluctuates with the reciprocating motion of the drive valve, the timing at which the load increases and the timing at which the current supply to the monocoil is accelerated are matched. Thus, the drive valve can be moved stably without losing the load. Moreover, since such an effect can be obtained without supplying an excessive current to the monocoil, an increase in power consumption can be prevented.

  Preferably, the coil is formed by a continuous line from a monocoil. According to the electromagnetically driven valve configured as described above, since the coil can be used between the electromagnet and the demagnetizing electromagnet, the cost can be reduced.

  An internal combustion engine according to the present invention is an internal combustion engine in which any one of the above-described electromagnetically driven valves is used for opening and closing between a combustion chamber and an exhaust port. The drive valve is formed at the tip of the valve shaft, and moves from the position that shields between the combustion chamber and the exhaust port into the combustion chamber as the drive valve moves from the closed position to the open position. It has further. When the drive valve moves from the closed position to the open position, the first arm member is attracted to the electromagnet by the electromagnetic force generated by the electromagnet, and the drive valve moves from the open position to the closed position. The second arm member is attracted to the electromagnet by the electromagnetic force generated by the electromagnet.

  According to the internal combustion engine configured as described above, when the drive valve moves from the closed position toward the open position, the internal pressure of the combustion chamber generated by the explosion process of the internal combustion engine is overcome, and the valve body is removed from the combustion chamber. Must be pushed into. In the present invention, at this timing, the drive valve can be moved using larger electromagnetic force energy. For this reason, the drive valve can be stably moved from the valve closing position to the valve opening position without causing a shortage of electromagnetic force or deterioration of power consumption.

  As described above, according to the present invention, it is possible to provide an electromagnetically driven valve capable of obtaining a stable movement of the drive valve while suppressing an increase in power consumption, and an internal combustion engine equipped with the electromagnetically driven valve. .

  Embodiments of the present invention will be described with reference to the drawings. In the drawings referred to below, the same or corresponding members are denoted by the same reference numerals.

(Embodiment 1)
1 is a cross-sectional view showing an electromagnetically driven valve according to Embodiment 1 of the present invention. The electromagnetically driven valve in the present embodiment constitutes an exhaust valve of an internal combustion engine such as a gasoline engine or a diesel engine. With reference to FIG. 1, in the electromagnetically driven valve 10, a parallel link mechanism is applied as a motion mechanism for reciprocating the drive valve 14.

  The electromagnetically driven valve 10 is connected to a drive valve 14 having a stem 12 and an umbrella portion 13 formed at the tip of the stem 12, and a lower that is connected to different positions of the stem 12 and swings by an applied electromagnetic force and elastic force. The disc 20 and the upper disc 30, the open / close electromagnet 60 (hereinafter also referred to simply as the electromagnet 60) that generates the electromagnetic force, and the lower disc 20 and the upper disc 30, respectively, are provided with an elastic force. The lower torsion bar 26 and the upper torsion bar 36 are provided. The drive valve 14 reciprocates in the direction indicated by the arrow 101 in response to the swinging motion of the lower disk 20 and the upper disk 30.

  The stem 12 includes a lower stem 12m continuous from the umbrella portion 13 and an upper stem 12n connected to the lower stem 12m via a connecting member 16. The connecting member 16 is formed of, for example, a pivot or a ball bearing so as to move flexibly between the lower stem 12m and the upper stem 12n. The lower stem 12m is formed to extend in one direction, and the upper stem 12n is connected to the lower stem 12m so as to extend obliquely in that direction. The direction in which the lower stem 12m extends coincides with the direction indicated by the arrow 101 that is the direction of movement of the drive valve 14. In the upper stem 12n, connecting pins 12p and 12q projecting from the outer peripheral surface are arranged in order from the position connected to the lower stem 12m and spaced from each other.

  The drive valve 14 is mounted on the cylinder head 41 in which the exhaust port 17 is formed. A valve seat 42 is provided at a position where the exhaust port 17 of the cylinder head 41 communicates with a combustion chamber (not shown). As the drive valve 14 reciprocates, the umbrella portion 13 is brought into close contact with the valve seat 42 or detached from the valve seat 42, whereby the exhaust port 17 is opened and closed. That is, when the stem 12 is raised, the driving valve 14 is positioned to the valve closing position, and when the stem 12 is lowered, the driving valve 14 is positioned to the valve opening position.

  The cylinder head 41 is provided with a valve guide 43 that guides the lower stem 12m so as to be slidable in the axial direction. The valve guide 43 is made of, for example, a metal material such as stainless steel so as to withstand high speed sliding with the lower stem 12m. On the top surface of the cylinder head 41, a disk support base 51 is attached at a position spaced apart from the stem 12.

  FIG. 2 is a perspective view showing the electromagnet in FIG. With reference to FIGS. 1 and 2, an electromagnet 60 is fixed to the disk support base 51 so as to be positioned between the lower disk 20 and the upper disk 30. The electromagnet 60 includes a coil 62 and a core 61 having attracting surfaces 61a and 61b and made of a magnetic material. The core 61 has a shaft portion 61p extending perpendicular to the direction in which the lower stem 12m extends, that is, the direction in which the drive valve 14 reciprocates. The coil 62 is provided so as to turn around the shaft portion 61p, and is composed of a monocoil (a coil composed of a continuous continuous line).

  The disk support 51 has a surface 51 a that faces the attracting surface 61 a of the electromagnet 60 and a surface 51 b that faces the attracting surface 61 b of the electromagnet 60. A space in which the upper disk 30 swings is defined between the suction surface 61a and the surface 51a, and a space in which the lower disk 20 swings is defined between the suction surface 61b and the surface 51b. Yes. The position where the upper disk 30 and the lower disk 20 are in contact with the surface 51a and the suction surface 61b, respectively, is the swing end on the valve closing side. The position where the upper disk 30 and the lower disk 20 are in contact with the adsorption surface 61a and the surface 51b is the swing end on the valve opening side. The drive valve 14 is positioned at the valve closing position and the valve opening position, respectively, when the upper disk 30 and the lower disk 20 are at the swinging ends on the valve closing side and the valve opening side, respectively.

  FIG. 3 is a perspective view showing the upper disk (lower disk) in FIG. 1. Referring to FIGS. 1 and 3, upper disk 30 has one end 33 and the other end 32, and extends from one end 33 toward the other end 32 in a direction crossing upper stem 12 n. The upper disk 30 is formed with rectangular surfaces 31a and 31b. The upper disk 30 is provided at an arm portion 31 extending between one end 33 and the other end 32 and at one end 33, and has a hollow cylindrical shape. It is comprised from the bearing part 38. FIG. The surfaces 31a and 31b face the attracting surface 61a of the electromagnet 60 and the surface 51a of the disk support base 51, respectively.

  The arm portion 31 is formed with a notch 39 located on the other end 32 side. Long holes 34 are formed in the wall surfaces of the notch 39 facing each other. The one end 33 defines a central axis 35 that extends perpendicular to both the direction in which the upper disk 30 extends and the direction in which the drive valve 14 reciprocates. A through hole 37 extending along the central axis 35 is formed in the bearing portion 38.

  The lower disk 20 corresponds to one end 33 and the other end 32 of the upper disk 30, the arm part 31, the surface 31 a, the surface 31 b, the notch part 39, the long hole 34, the bearing part 38, the through hole 37, and the central shaft 35. And one end 23, the other end 22, an arm portion 21, a surface 21 b, a surface 21 a, a notch portion 29, a long hole 24, a bearing portion 28, a through hole 27 and a central shaft 25. The surfaces 21a and 21b face the attracting surface 61b of the electromagnet 60 and the surface 51b of the disk support base 51, respectively. The lower disk 20 is formed such that the distance from one end 23 to the other end 22 is longer than the distance from one end 33 to the other end 32 of the upper disk 30. The upper disk 30 and the lower disk 20 are made of a magnetic material.

  The other end 32 of the upper disk 30 is swingably connected to the upper stem 12n by inserting the connecting pin 12q through the elongated hole 34. The other end 22 of the lower disk 20 is swingably connected to the upper stem 12n by inserting the connecting pin 12p through the long hole 24. One end 33 of the upper disk 30 is swingably supported by a disk support 51 via an upper torsion bar 36 inserted into the through hole 37. One end 23 of the lower disk 20 is swingably supported by a disk support 51 via a lower torsion bar 26 inserted into the through hole 27.

  With such a configuration, when the upper disk 30 and the lower disk 20 are swung around the center shafts 35 and 25, respectively, the swinging motion is transmitted as a linear motion from the upper stem 12n to the lower stem 12m. As a result, the drive valve 14 reciprocates. In this way, the drive system is called a rotational drive system as opposed to a translational drive system.

  The distance between the position where one end 33 of the upper disk 30 is supported by the disk support base 51 and the position where the other end 32 is connected to the stem 12, that is, the central shaft 35 and the long hole 34 are inserted. The distance between the connecting pin 12q is La, and the distance between the position where one end 23 of the lower disk 20 is supported by the disk support base 51 and the position where the other end 22 is connected to the stem 12, that is, When the distance between the central shaft 25 and the connecting pin 12p inserted through the long hole 24 is Lb, the upper disk 30 and the lower disk 20 are provided so as to satisfy the relationship La <Lb. .

  When the center line 106 passing through the central axes 35 and 25 is defined, the upper disk 30 and the lower disk 20 are parallel to the direction in which the lower stem 12m extends, that is, the direction in which the drive valve 14 reciprocates. The disc support 51 is supported so as to extend. Further, when the center lines 107 are defined by connecting the centers of the suction surfaces 61a and 61b in the direction in which the shaft portion 61p extends, the electromagnet 60 is arranged so that the center lines 106 and 107 extend parallel to each other. 51 is fixed. Assuming that the distance between the center line 106 and the center line 107 is Lc, the electromagnetic force generated by the electromagnet 60 is applied to the upper disk 30 and the lower disk 20 at positions separated from the center axes 35 and 25 by the distance Lc, respectively. Works. That is, the distance between the fulcrum at which the disk swings and the position where the electromagnetic force generated by the electromagnet 60 acts on the disk is the same for the upper disk 30 and the lower disk 20.

  With such a configuration, it is not necessary to dispose the one end 23 of the lower disk 20 at a position deeper than the one end 33 of the upper disk 30 when viewed from the drive valve 14. Thereby, even if the disk support base 51 has a shape extending in parallel with the lower stem 12m, it is not necessary to provide a large notch shape for supporting the lower disk 20, and the strength of the disk support base 51 can be ensured. Further, since the positional relationship between the upper disk 30 and the lower disk 20 with respect to the electromagnet 60 is symmetric with respect to the top and bottom of the shaft portion 61p, the gap between the electromagnet and these disks can be set with high accuracy. .

  Due to the upper torsion bar 36, a counterclockwise elastic force about the central axis 35 acts on the upper disk 30. Due to the lower torsion bar 26, a clockwise elastic force about the central axis 25 acts on the lower disk 20. In a state where the electromagnetic force by the electromagnet 60 is not applied, the lower disk 20 and the upper disk 30 are moved between the opening end and the closing end by the lower torsion bar 26 and the upper torsion bar 36. Is positioned at an intermediate position. At this intermediate position, the distance from the surface 31a of the upper disk 30 to the attracting surface 61a of the electromagnet 60 is equal to the distance from the surface 21a of the lower disk 20 to the attracting surface 61b of the electromagnet 60.

  When a current is supplied to the coil 62, an electromagnetic force is generated, and a force that attracts the surface 31a to the attracting surface 61a acts on the upper disk 30. As a result, the upper disk 30 tries to swing counterclockwise about the central axis 35 and applies a force in a direction to push down the upper stem 12n (a force to move the drive valve 14 toward the valve opening position). And act on the drive valve 14. Further, since the electromagnetically driven valve 10 uses the electromagnet 60 formed of a monocoil, a force that attracts the surface 21a to the attracting surface 61b also acts on the lower disk 20. As a result, the lower disk 20 tries to swing clockwise about the central axis 25, and the force in the direction to push up the upper stem 12n (force to move the drive valve 14 toward the valve closing position) It acts on the drive valve 14. The electromagnetic force generated by the electromagnet 60 acts greatly at a position close to the electromagnet 60 and acts small at a distance. For this reason, the magnitude | size of these force which acts on the drive valve 14 changes with the reciprocation of the drive valve 14. FIG.

  FIG. 4 is a graph showing the relationship between the lift position of the drive valve and the force acting on the drive valve in the electromagnetically driven valve in FIG. FIG. 5 is a graph showing the relationship between the lift position of the drive valve and the force acting on the drive valve in the electromagnetic drive valve for comparison. For comparison with the electromagnetically driven valve 10 in FIG. 1, the distance between the position where the upper disk and the lower disk are supported at one end and the position where the other end is connected to the stem 12 is equal to each other. FIG. 5 shows the relationship between the two of the electromagnetically driven valves.

  4 and 5, the vertical axis in the figure indicates the force acting on the drive valve 14, and the force to be moved toward the valve closing position is positive and the valve opening position is positive. The value is expressed with negative force to move toward. The forces acting on the drive valve 14 from the lower disk 20 and the upper disk 30 are indicated by curves 121 and 122, respectively. The resultant force, that is, the electromagnetic force generated by the electromagnet 60 acts on the drive valve 14. The resultant force is indicated by curve 123.

  As can be seen from FIG. 5, in the electromagnetically driven valve for comparison, the distance from the adsorption surface 61a of the electromagnet 60 to the surface 31a of the upper disk 30 and the distance from the adsorption surface 61b of the electromagnet 60 to the surface 21a of the lower disk 20 Is equal to the intermediate position, and the resultant force acting on the drive valve 14 indicated by the curve 123 becomes zero.

  On the other hand, in the electromagnetically driven valve 10 in the present embodiment, as can be seen from FIG. 4, the distance between the position where one end is supported and the position where the other end is connected to the stem 12 is the upper disk 30 and Because of the difference between the lower disks 20, the force acting on the drive valve 14 from the upper disk 30 is larger than the force acting on the drive valve 14 from the lower disk 20 at the intermediate position.

  More specifically, assuming that when the upper disk 30 and the lower disk 20 are in the intermediate position, an attractive force F acts on the upper disk 30 and the lower disk 20 due to the electromagnetic force generated by the electromagnet 60, the upper stem 12n A force having a magnitude of F × Lc / La acts from the upper disk 30, and a force having a magnitude of F × Lc / Lb acts from the lower disk 20. Since the relationship of La <Lb is established, even if an attracting force having the same magnitude acts on the upper disk 30 and the lower disk 20 from the electromagnet 60, the force acting on the drive valve 14 from the upper disk 30 is reduced. The force acting on the drive valve 14 from the disk 20 becomes larger.

  Therefore, in the electromagnetically driven valve 10 according to the present embodiment, as shown by the curve 123 in FIG. 4, the lift position where the resultant force of the force acting on the drive valve 14 becomes 0 is closer to the valve closing side than the intermediate position. It becomes the position.

  FIG. 6 is a schematic diagram showing an upper disk and a lower disk at the swing end on the valve closing side. FIG. 7 is a schematic diagram showing an upper disk and a lower disk that are directed from the valve closing side rocking end to the valve opening side rocking end. FIG. 8 is a schematic diagram showing an upper disk and a lower disk at the swing end on the valve opening side. Subsequently, the operation of the electromagnetically driven valve 10 will be described.

  Referring to FIG. 6, when the drive valve 14 is in the closed position, the coil 62 is supplied with a current that flows in the direction indicated by the arrow 111 around the shaft portion 61p. Magnetic flux flows through the core 61, and an electromagnetic force that attracts the lower disk 20 to the attracting surface 61b of the electromagnet 60 is generated. The upper disk 30 and the lower disk 20 are held at the swinging end on the valve closing side shown in the figure against the elastic force of the upper torsion bar 36.

  With reference to FIG. 7, next, the current supply to the coil 62 is stopped, and the electromagnetic force generated in the electromagnet 60 is extinguished. As a result, the lower disk 20 is detached from the suction surface 61b and starts to swing toward the intermediate position by the elastic force of the upper torsion bar 36. Next, before the upper disk 30 and the lower disk 20 reach the intermediate position, a current that flows in the direction indicated by the arrow 111 around the shaft portion 61p is supplied to the coil 62. Magnetic flux flows through the core 61, and an electromagnetic force that attracts the upper disk 30 to the attracting surface 61a of the electromagnet 60 is generated. The upper disk 30 and the lower disk 20 swing toward the intermediate position by the electromagnetic force and the elastic force of the upper torsion bar 36. At this time, the electromagnet 60 also generates an electromagnetic force that draws the lower disk 20 to the attracting surface 61 b of the electromagnet 60. However, in the present embodiment, the lift position where the resultant force of the force acting on the drive valve 14 by the electromagnetic force becomes zero is located at a position close to the valve closing side from the intermediate position. For this reason, even if the current supply to the coil 62 is started before the upper disk 30 and the lower disk 20 reach the intermediate position, the upper disk 30 and the lower disk 20 are continuously swung toward the intermediate position. Can be made.

  Referring to FIG. 8, after passing the intermediate position, the upper disk 30 and the lower disk 20 are opposed to the elastic force of the lower torsion bar 26 by the electromagnetic force that pulls the upper disk 30 to the attracting surface 61 a of the electromagnet 60. It swings to the swing end on the valve opening side shown in the figure.

  Referring to FIG. 6, thereafter, the current supply to coil 62 is stopped, and the electromagnetic force generated in electromagnet 60 is extinguished. As a result, the upper disk 30 is detached from the suction surface 61a and begins to swing again toward the intermediate position by the elastic force of the lower torsion bar 26. Next, when the upper disk 30 and the lower disk 20 reach the intermediate position and further swing over the position beyond the intermediate position, a current that flows in the direction indicated by the arrow 111 around the shaft portion 61p is supplied to the coil 62. To do. Magnetic flux flows through the core 61, and an electromagnetic force that attracts the lower disk 20 to the attracting surface 61b of the electromagnet 60 is generated. The upper disk 30 and the lower disk 20 swing to the swinging end on the valve closing side in the figure while countering the elastic force of the upper torsion bar 36 by this electromagnetic force.

  Thereafter, the start and stop of the current supply to the coil 62 are repeated at the timing described above. Accordingly, the upper disk 30 and the lower disk 20 are swung between the displacement ends on the valve opening side and the valve closing side, and the driving valve 14 is reciprocated by this rocking movement.

  FIG. 9 is a graph showing the relationship between the lift position of the drive valve and the current value supplied to the coil. Referring to FIG. 9, when the upper disk 30 and the lower disk 20 are swung from the valve-closing-side rocking end toward the valve-opening-side rocking end as shown in FIG. Cylinder internal pressure is generated in the combustion chamber of the internal combustion engine equipped with the valve 10 due to the explosion process. Therefore, in order to obtain a stable operation of the electromagnetically driven valve 10, it is necessary to cause the drive valve 14 to have a force that can overcome the internal pressure and push the umbrella portion 13 into the combustion chamber.

  In the electromagnetically driven valve for comparison assumed when referring to FIG. 5, the position where the resultant force of the force acting on the drive valve 14 is 0 is the intermediate position, so that the upper disk 30 and the lower disk 20 are closed. When swinging from the swing end on the valve side toward the swing end on the valve opening side, the start of current supply to the coil 62 is at a timing beyond the intermediate position. However, in the present embodiment, the current supply to the coil 62 can be started before the upper disk 30 and the lower disk 20 reach the intermediate position (time Tx in FIG. 9). For this reason, when the drive valve 14 is opened, larger electromagnetic force energy can be input for the movement of the drive valve 14. Thereby, the drive valve 14 can be stably moved from the valve closing position to the valve opening position without causing insufficient electromagnetic force.

  Further, when the internal combustion engine is at a low load, the internal pressure generated in the combustion chamber is relatively small, so that there is a margin in the electromagnetic force energy required when the drive valve 14 is opened. Therefore, in this case, the current value supplied to the coil 62 can be reduced from Ia to Ib at the time of high load, and power consumption corresponding to the area of the region 55 in FIG. 9 can be reduced.

  On the other hand, when the upper disk 30 and the lower disk 20 swing from the swinging end on the valve opening side toward the swinging end on the valve closing side, the start of current supply to the coil 62 is started. When 20 reaches the intermediate position, the timing further swings the position beyond the intermediate position. However, since the cylinder internal pressure does not act on the drive valve 14 that moves from the valve-opening position toward the valve-closed position, the drive valve 14 moves stably as in the valve-opening. be able to.

  In the present embodiment, the upper disk 30 and the lower disk 20 can be swung and the drive valve 14 can be reciprocated only by providing the electromagnet 60 made of a monocoil. For this reason, compared with the case where two electromagnets for valve opening and valve closing are provided, the number of parts of the electromagnet having a high cost weight can be reduced to ½. Further, since only the current supply to the coil 62 is required, the number of circuit elements provided in an EDU (electronic driver unit) and one required for each coil can be reduced to ½ as with the electromagnet. . In the present embodiment, the description has been given focusing on one exhaust valve. However, the internal combustion engine is provided with a plurality of valves, and an electromagnetically driven valve is required for each valve. For this reason, if it sees as the whole internal combustion engine, a significant cost reduction is attained.

  Further, when the drive valve 14 is in an intermediate position, the rotary drive type is compared with the translation drive type electromagnetic drive valve in which the electromagnet and the armature of the drive valve on which the electromagnetic force acts are uniformly separated. In the electromagnetically driven valve 10, the distance from the electromagnet 60 to the upper disk 30 decreases as it approaches the one end 33, and the distance from the electromagnet 60 to the lower disk 20 decreases as it approaches the one end 23. Since a large electromagnetic force acts at a position where the distance from the electromagnet is small, the drive valve 14 can be moved more stably regardless of the cylinder internal pressure generated in the combustion chamber.

  The electromagnetically driven valve 10 according to the first embodiment of the present invention is provided with a drive valve 14 having a stem 12 as a valve shaft, spaced apart from each other, and reciprocally moves the drive valve 14 by swinging. An upper disk 30 and a lower disk 20 as second arm members, and a coil 62 as a monocoil, and an opening / closing electromagnet 60 as an electromagnet disposed between the upper disk 30 and the lower disk 20 are provided. The upper disk 30 and the lower disk 20 have one ends 33 and 23 supported to be swingable and the other ends 32 and 22 connected to the stem 12. The electromagnet 60 causes an electromagnetic force to act on the upper disk 30 and the lower disk 20 by supplying current to the coil 62, thereby swinging the upper disk 30 and the lower disk 20. The distance between the position where the one ends 33 and 23 are swingably supported and the position where the other ends 32 and 22 are connected to the stem 12 is smaller in the upper disk 30 than in the lower disk 20.

  The electromagnetically driven valve 10 is an electromagnetically driven valve used for opening and closing between the combustion chamber of the internal combustion engine and the exhaust port 17. The drive valve 14 is formed at the tip of the stem 12 and moves from a position that shields between the combustion chamber and the exhaust port 17 into the combustion chamber as the drive valve 14 moves from the closed position to the open position. It further has the umbrella part 13 as a valve body to perform.

  According to the electromagnetically driven valve 10 according to Embodiment 1 of the present invention configured as described above, the position where the forces acting on the drive valve 14 from the upper disk 30 and the lower disk 20 are balanced from the intermediate position to the valve closing side. By shifting, it is possible to input larger electromagnetic force energy to the movement of the drive valve 14 from the valve closing position toward the valve opening position. Thereby, the drive valve 14 can be stably moved from the valve closing position to the valve opening position without causing insufficient electromagnetic force. Further, even if the cylinder internal pressure increases, the electromagnetically driven valve 10 can be stably operated, so that the output of the internal combustion engine can be improved. Further, when the internal combustion engine is at a low load, the fuel consumption of the internal combustion engine can be improved by reducing power consumption.

(Embodiment 2)
FIG. 10 is a sectional view showing an electromagnetically driven valve according to Embodiment 2 of the present invention. The electromagnetically driven valve in the present embodiment basically has the same structure as that of the electromagnetically driven valve 10 in the first embodiment. Hereinafter, the description of the overlapping structure will not be repeated.

  With reference to FIG. 10, in the present embodiment, the angle at which the upper disk 30 swings about the central axis 35 is smaller than the angle at which the lower disk 20 swings about the central axis 25. An electromagnet 60 and a disk support base 51 are formed. The electromagnet 60 and the disk support base 51 are formed such that the inclination of the adsorption surface 61a and the surface 51a with respect to the direction in which the shaft portion 61p extends is smaller than the inclination of the adsorption surface 61b and the surface 51b.

  FIG. 11 is a graph showing the relationship between the lift position of the drive valve and the force acting on the drive valve in the electromagnetically driven valve in FIG. Referring to FIGS. 10 and 11, in the present embodiment, upper disk 30 and lower disk 20 are in the middle between the swinging end on the valve opening side and the swinging end on the valve closing side (in FIG. 11). The distance Ld from the surface 31a to the suction surface 61a is smaller than the distance Le from the surface 21a to the suction surface 61b. For this reason, the intermediate position where the distance from the surface 31a to the attracting surface 61a and the distance from the surface 21a to the attracting surface 61b are equal is shifted to the valve closing side, whereby the electromagnetic force generated by the electromagnet 60 is The position at which an attracting force having the same magnitude as that of the upper disk 30 and the lower disk 20 is also shifted to the valve closing side.

  Therefore, in the present embodiment, the resultant force of the force acting on the drive valve 14 by the electromagnetic force is 0 due to a synergistic effect with the magnitude relationship between the position where the one end is supported and the position where the other end is connected to the stem 12. The lift position can be set at a position closer to the valve closing side than the electromagnetically driven valve 10 in the first embodiment.

  According to the electromagnetically driven valve according to the second embodiment of the present invention configured as described above, the start of current supply to the coil 62 when the drive valve 14 moves from the valve closing position to the valve opening position is further accelerated. Can be done. Thereby, the effect described in the first embodiment can be obtained more effectively.

(Embodiment 3)
12 is a sectional view showing an electromagnetically driven valve according to Embodiment 3 of the present invention. The electromagnetically driven valve in the present embodiment basically has the same structure as that of the electromagnetically driven valve 10 in the first embodiment. Hereinafter, the description of the overlapping structure will not be repeated.

  Referring to FIG. 12, in the electromagnetically driven valve 110 according to the present embodiment, a position where one end 33 of the upper disk 30 is supported by the disk support base 51 and a position where the other end 32 is connected to the stem 12. The distance between the central axis 35 and the connecting pin 12q inserted through the elongated hole 34 is determined by the position where one end 23 of the lower disk 20 is supported by the disk support base 51 and the other end 22 Is equal to the distance between the position connected to the stem 12, that is, the distance between the central shaft 25 and the connecting pin 12 p inserted through the long hole 24. Is provided.

  The upper stem 12n and the lower stem 12m have end faces 12b and 12a that face each other. The upper stem 12n is connected to the lower stem 12m with the end surface 12b in contact with the end surface 12a. The upper stem 12n is connected to the lower stem 12m so as to extend in the direction in which the lower stem 12m extends, that is, in the direction in which the drive valve 14 reciprocates.

  An electromagnet 70 is fixed to the disk support 51 at a position opposite to the electromagnet 60 across the lower disk 20. The electromagnet 70 includes a coil 62 and a core 71 having an attracting surface 71a and made of a magnetic material. The core 71 has a shaft portion 71 p extending in parallel with the shaft portion 61 p of the electromagnet 60. The coil 62 extends continuously from the electromagnet 60 and is provided so as to turn around the shaft portion 71p. The suction surface 71a faces the surface 21b of the lower disk 20, and a space in which the lower disk 20 swings is defined between the suction surface 71a and the suction surface 61b of the electromagnet 60.

  Currents flowing in the directions indicated by arrows 151 and 152 around the shaft portions 61p and 71p are supplied to the coils 62 of the electromagnets 60 and 70, respectively. Thereby, in the electromagnet 60, the magnetic flux which flows in the direction shown by the arrow 153 is formed between the core 61 and the lower disk 20, and in the electromagnet 70, the direction shown by the arrow 154 is formed between the core 71 and the lower disk 20. Is formed. These magnetic fluxes flow in opposite directions in the lower disk 20, and the magnetic flux generated by the electromagnet 60 is offset and weakened by the magnetic flux generated by the electromagnet 70. As a result, the force with which the lower disk 20 is attracted to the attracting surface 61 b of the electromagnet 60 is smaller than that when only the electromagnet 60 is provided.

  FIG. 13 is a graph showing the relationship between the lift position of the drive valve and the force acting on the drive valve in the electromagnet in FIG. Referring to FIGS. 12 and 13, the force acting on the drive valve 14 from the lower disk 20 by the electromagnetic force generated by the electromagnet 70 is shown by a curve 124 in the drawing. In the present embodiment, by providing the electromagnet 70, the force acting on the drive valve 14 from the upper disk 30 becomes larger than the force acting on the drive valve 14 from the lower disk 20. As a result, the lift position where the resultant force of the force acting on the drive valve 14 by the electromagnetic force becomes zero is a position close to the valve closing side from the intermediate position.

  An electromagnetically driven valve 110 according to Embodiment 3 of the present invention is provided with a drive valve 14 having a stem 12 as a valve shaft, spaced apart from each other, and reciprocally moves the drive valve 14 by swinging. An upper disk 30 and a lower disk 20 as second arm members, and an electromagnet which is arranged between the upper disk 30 and the lower disk 20 and swings the upper disk 30 and the lower disk 20 by applying an electromagnetic force. An electromagnet 60 for both opening and closing and an electromagnet 70 as a demagnetizing electromagnet provided on the opposite side of the electromagnet 60 across the lower disk 20 are provided. The upper disk 30 and the lower disk 20 have one ends 33 and 23 supported to be swingable and the other ends 32 and 22 connected to the stem 12. The electromagnet 60 has a coil 62 as a monocoil, and the electromagnet 70 has a coil 62. By supplying the current to the coil 62 of the electromagnet 60, a magnetic flux flowing in a predetermined direction is formed in the lower disk 20, and by supplying the current to the coil 62 of the electromagnet 70, the magnetic disk 70 has a direction opposite to the predetermined direction. A flowing magnetic flux is formed.

  The electromagnetically driven valve 110 is an electromagnetically driven valve used for opening and closing between the combustion chamber of the internal combustion engine and the exhaust port 17. The drive valve 14 is formed at the tip of the stem 12 and moves from a position that shields between the combustion chamber and the exhaust port 17 into the combustion chamber as the drive valve 14 moves from the closed position to the open position. It further has the umbrella part 13 as a valve body to perform.

  According to the electromagnetically driven valve 110 according to the third embodiment of the present invention configured as described above, the start of current supply to the coil 62 when the drive valve 14 moves from the valve closing position to the valve opening position is performed at the intermediate position. This can be done at an earlier timing. Thereby, the effect similar to the effect described in Embodiment 1 can be acquired.

  In the present embodiment, the electromagnet 70 is provided with the coil 62 continuously extending from the electromagnet 60. However, the current supply can be controlled independently of the coil 62, that is, the coil 62. A coil that can be formed may be provided in the electromagnet 70. In the electromagnetically driven valve 110, the lift position at which the resultant force of the force acting on the drive valve 14 becomes zero is fixed by the number of turns of the coil 62 with respect to the shaft portion 71p. In this case, the lift position is freely set. it can. For this reason, when the internal combustion engine is at a low load, the start of the current supply can be delayed until the optimum time, and the power consumption can be further reduced.

  In the first to third embodiments, the case where the electromagnetically driven valve according to the present invention is applied to an exhaust valve of an internal combustion engine has been described. However, it can also be applied to an intake valve. Further, a new electromagnetically driven valve may be configured by appropriately combining the electromagnetically driven valves in the first to third embodiments.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is sectional drawing which shows the electromagnetically driven valve in Embodiment 1 of this invention. It is a perspective view which shows the electromagnet in FIG. It is a perspective view which shows the upper disk (lower disk) in FIG. 2 is a graph showing the relationship between the lift position of the drive valve and the force acting on the drive valve in the electromagnetically driven valve in FIG. 1. In the electromagnetically driven valve for comparison, it is a graph which shows the relationship between the lift position of a drive valve, and the force which acts on a drive valve. It is a schematic diagram which shows the upper disk and lower disk in the rocking | fluctuation end by the side of a valve closing. FIG. 5 is a schematic diagram showing an upper disk and a lower disk heading from a valve closing side swing end to a valve opening side swing end. It is a schematic diagram showing an upper disk and a lower disk at the swing end on the valve opening side. It is a graph which shows the relationship between the lift position of a drive valve, and the electric current value supplied to a coil. It is sectional drawing which shows the electromagnetically driven valve in Embodiment 2 of this invention. 11 is a graph showing the relationship between the lift position of the drive valve and the force acting on the drive valve in the electromagnetically driven valve in FIG. 10. It is sectional drawing which shows the electromagnetically driven valve in Embodiment 3 of this invention. 13 is a graph showing the relationship between the lift position of the drive valve and the force acting on the drive valve in the electromagnet in FIG. 12.

Explanation of symbols

  10, 110 Electromagnetic drive valve, 12 stem, 13 umbrella part, 14 drive valve, 17 exhaust port, 20 lower disk, 22, 32 other end, 23, 33 one end, 30 upper disk, 60 open / close electromagnet, 62 coil, 70 Electromagnet.

Claims (6)

A drive valve having a valve stem;
A first end and a second end having a first end rotatably supported and a second end connected to the valve shaft; the first end and the second end are provided to be spaced apart from each other; Arm members of
A monocoil, disposed between the first arm member and the second arm member, and by supplying an electric current to the monocoil, an electromagnetic force is applied to the first and second arm members; An electromagnet that swings the first and second arm members;
The distance between the position where the one end is swingably supported and the position where the other end is connected to the valve shaft is greater for the first arm member than for the second arm member. Small, electromagnetically driven valve.   The first and second arm members are supported such that the one end of the first arm member is swingably supported and the one end of the second arm member is swingably supported. The electromagnetically driven valve according to claim 1, wherein a straight line connecting positions is provided so as to extend in parallel with a direction in which the drive valve reciprocates.   The electromagnetically driven valve according to claim 1 or 2, wherein an angle at which the first arm member swings around a position where the one end is supported is smaller than an angle at which the second arm member swings. . A drive valve having a valve stem;
A first end and a second end having a first end rotatably supported and a second end connected to the valve shaft; the first end and the second end are provided to be spaced apart from each other; Arm members of
An electromagnet having a monocoil, disposed between the first arm member and the second arm member, and configured to swing the first and second arm members by applying electromagnetic force;
A demagnetizing electromagnet provided on the opposite side of the electromagnet with a coil and sandwiching the second arm member,
A magnetic flux flowing in a predetermined direction is formed in the second arm member by supplying current to the monocoil, and a direction opposite to the predetermined direction in the second arm member by supplying current to the coil. An electromagnetically driven valve in which a magnetic flux that flows through is formed.   The electromagnetically driven valve according to claim 4, wherein the coil is formed by a continuous line extending from the monocoil. The electromagnetically driven valve according to any one of claims 1 to 5, wherein the electromagnetically driven valve is used for opening and closing between a combustion chamber and an exhaust port,
The drive valve is formed at the tip of the valve shaft, and moves from a position that shields between the combustion chamber and the exhaust port into the combustion chamber as the drive valve moves from the closed position to the open position. And further has a valve body
When the drive valve moves from the closed position to the open position, the first arm member is attracted to the electromagnet by the electromagnetic force generated by the electromagnet, and the drive valve is closed from the open position. An internal combustion engine in which the second arm member is attracted to the electromagnet by an electromagnetic force generated by the electromagnet when moving toward a position.

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