JP2012180767A - Pulsation absorbing device for hydraulic circuit and valve train device for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pulsation absorbing device for a hydraulic circuit enhancing durability of a flexible membrane member, and to provide a valve train device for an internal combustion engine.SOLUTION: This pulsation absorbing device for the hydraulic circuit includes: an oil chamber connecting to an oil passage of a hydraulic circuit; an air chamber containing gas; a plate-shaped flexible membrane member separating the air chamber and the oil chamber; and a flexible membrane deformation suppression member internally existing in the air chamber and in contact with the flexible membrane member to suppress the deformation of the flexible membrane member. This valve train device for an internal combustion engine includes: a valve driving piston capable of driving an exhaust valve or an intake valve of an internal combustion engine; and an oil passage of the hydraulic circuit connecting to the inside of a valve driving cylinder where the valve driving piston is reciprocated. The pulsation of the oil passage of the hydraulic circuit connecting to the inside of the valve driving cylinder is absorbed by the pulsation absorbing device for the hydraulic circuit.

Description

  The present invention relates to a pulsation absorbing device for a hydraulic circuit for absorbing pulsation of a hydraulic circuit, and a valve operating device for an internal combustion engine for driving an intake valve and an exhaust valve of the internal combustion engine.

  For example, Patent Document 1 discloses a fuel discharge chamber formed between a fuel outflow hole of a pump working chamber and a fuel discharge port of a pulsating pressure fuel pump, and an air for relaxing pulsation pressure generated in the fuel discharge chamber. A flexible membrane member that separates the chamber is described.

Japanese Patent Laid-Open No. 9-014075

  By the way, when the flexible membrane member of the pulsating pressure fuel pump described in Patent Document 1 is applied to a hydraulic circuit, the pulsation absorption mechanism can be made small, but the flexible membrane member is affected by fluctuations in hydraulic pressure. There is a risk that it cannot be tolerated. For this reason, in the conventional hydraulic circuit, an accumulator such as a prada type or a piston type is attached to absorb pulsation, but it is difficult to reduce the size.

  The present invention solves the above-described problems, and an object thereof is to provide a pulsation absorbing device for a hydraulic circuit and a valve operating device for an internal combustion engine in which durability of a flexible membrane member is increased.

  In order to achieve the above object, a pulsation absorber for a hydraulic circuit according to the present invention includes an oil chamber connected to an oil passage of the hydraulic circuit, an air chamber containing gas, and a plate that separates the air chamber and the oil chamber. And a flexible membrane deformation suppressing member that is in the air chamber and that is in contact with the flexible membrane member and suppresses deformation of the flexible membrane member. Features.

  Thereby, the possibility that the flexible membrane member cannot withstand the fluctuation of the hydraulic pressure transmitted to the oil chamber can be reduced. For this reason, the pulsation absorbing device for a hydraulic circuit in which the durability of the flexible membrane member is improved can be used as a flat flexible membrane member and can be reduced in size.

  As a desirable aspect of the present invention, it is preferable that the flexible membrane deformation suppressing member is a material having voids inside. Thereby, the material which has a space | gap inside contains gas, and gas can change the volume according to the change of a pressure. For this reason, pulsation is absorbed. Moreover, the flexible film | membrane deformation | transformation suppression member can suppress the excessive deformation | transformation of a plate-shaped flexible film | membrane member. The material having voids inside is more preferably a foamed resin.

  As a desirable aspect of the present invention, the flexible membrane deformation suppressing member preferably includes a bellows-like elastic member and a locking member that suppresses deformation of the bellows-like elastic member. Thereby, the said bellows-like elastic member contains gas, and gas can change the volume according to the change of a pressure. For this reason, pulsation is absorbed. Moreover, the flexible film | membrane deformation | transformation suppression member can suppress the excessive deformation | transformation of a plate-shaped flexible film | membrane member.

  As a desirable aspect of the present invention, the oil chamber is preferably connected to a plurality of oil passages of the hydraulic circuit. Thereby, the pulsation absorbing device for the hydraulic circuit is shared by the plurality of oil passages, and the entire hydraulic system becomes small.

  In order to achieve the above-described object, a valve operating apparatus for an internal combustion engine according to the present invention is connected to a valve drive piston capable of driving an exhaust valve or an intake valve of the internal combustion engine and a valve drive cylinder in which the valve drive piston reciprocates. The hydraulic circuit pulsation absorbing device absorbs the pulsation of the hydraulic circuit of the hydraulic circuit connected to the inside of the valve drive cylinder.

  Thereby, the pulsation of the oil passage is absorbed, and the possibility that unnecessary vibration is added to the operation of the valve drive piston is reduced. As a result, the valve operating device for the internal combustion engine having the pulsation absorbing device for hydraulic circuit in which the durability of the flexible membrane member is enhanced.

  ADVANTAGE OF THE INVENTION According to this invention, the pulsation absorber for hydraulic circuits which improved durability of the flexible film | membrane member, and the valve operating apparatus of an internal combustion engine can be provided.

FIG. 1 is a configuration diagram of a valve gear for an internal combustion engine according to the first embodiment. FIG. 2 is a schematic diagram of the valve drive device. FIG. 3 is a configuration diagram of the control device. FIG. 4 is an explanatory diagram illustrating an example of a hydraulic circuit according to the present embodiment. FIG. 5 is a schematic diagram illustrating the pulsation absorbing device for a hydraulic circuit according to the first embodiment. FIG. 6 is a schematic diagram illustrating the flexible membrane member according to the first embodiment. FIG. 7 is a schematic diagram illustrating the flexible membrane deformation suppressing member according to the first embodiment. FIG. 8 is a schematic diagram illustrating a pulsation absorbing device for a hydraulic circuit according to the second embodiment. FIG. 9 is a schematic view showing a flexible membrane deformation suppressing member according to the third embodiment.

  DESCRIPTION OF EMBODIMENTS Embodiments (embodiments) for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited by the contents described in the following embodiments. The constituent elements described below include those that can be easily assumed by those skilled in the art and those that are substantially the same. Furthermore, the constituent elements described below can be appropriately combined.

(Embodiment 1)
The first embodiment will be described with reference to the drawings. FIG. 1 is a configuration diagram of a valve gear for an internal combustion engine according to the first embodiment. FIG. 2 is a schematic diagram of the valve drive device. FIG. 3 is a configuration diagram of the control device. The valve operating apparatus 100 for an internal combustion engine according to the first embodiment has a hydraulic circuit which will be described later, and the valve driving apparatus 10 is operated by hydraulic pressure, so that the combustion piston 2 in the cylinder block 3 moves up and down. It is a device that drives an exhaust valve 4a and an intake valve 4b as engine valves. As will be described later, in the first embodiment, a pulsation absorbing device for a hydraulic circuit is connected to an oil passage connecting the direction switching control valve mechanism and the valve drive cylinder upper chamber of the valve drive cylinder to absorb pulsation. It is characterized by.

  As shown in FIG. 1, the valve operating device 100 includes a valve driving device 10 installed in the internal combustion engine 1 (engine), measuring devices 20 and 21 that measure the state of the internal combustion engine 1, Is provided with a hydraulic unit 30 for supplying pressure, a control device 80 for controlling the valve driving device 10, signal lines I1, I2, I3, I4, and I5, and hydraulic lines O1 and O2. The dynamo 200 is a power conversion device. The dynamo 200 is not an essential component but an additional element, and is used, for example, when used as a test apparatus.

  As shown in FIG. 2, the valve drive device 10 includes a valve drive cylinder 11, a valve drive piston 12 movably accommodated in the valve drive cylinder 11, and a servo valve 13 for driving the valve drive piston 12. And a valve drive piston displacement meter 15 for measuring the position of the valve drive piston 12. As shown in FIG. 1, the internal combustion engine 1 includes a cylinder block 3, a crankcase 9, a combustion piston 2, a crankshaft 7, and a connecting rod 8. The combustion piston 2 and the crankshaft 7 are connected by a connecting rod 8. With such a structure, the reciprocating motion of the combustion piston is converted into rotational motion by the crankshaft 7.

  As shown in FIGS. 1 and 2, the internal combustion engine 1 includes an exhaust valve 4 a and an intake valve 4 b, a valve rod 5, and a valve spring 6. The exhaust valve 4 a and the intake valve 4 b are each fixed to the lower end of the valve rod 5, and force is urged in the valve closing direction by a valve spring 6 provided on the valve rod 5. The valve drive device 10 is mounted on the internal combustion engine 1, and a valve drive piston 12 is connected to the valve rod 5. Alternatively, the valve driving device 10 is disposed with a slight gap when the valve is closed. Thus, when the valve drive piston 12 is driven, the exhaust valve 4 a and the intake valve 4 b are driven according to the valve rod 5. When the valve drive piston 12 is connected to the valve rod 5, the valve spring 6 is not necessary.

  The valve drive piston 12 movably accommodated in the valve drive cylinder 11 shown in FIG. 2 is a hydraulic actuator, and the valve drive piston 12 extends when the hydraulic pressure is supplied to the valve drive cylinder 11 and extends to the exhaust valve 4a or The intake valve 4b is opened. Further, the valve drive piston 12 contracts when the hydraulic pressure is discharged from the valve drive cylinder 11, and closes the exhaust valve 4a or the intake valve 4b. The servo valve 13 is attached to the outer side surface 11 </ b> A of the valve drive cylinder 11. The servo valve 13 is connected to a later-described hydraulic unit 30 through a hydraulic line O1 that is a hydraulic supply line and a hydraulic line O2 that is a return line. The servo valve 13 controls the supply of hydraulic pressure to the valve drive cylinder 11 or the discharge of hydraulic pressure from the valve drive cylinder 11 based on an instruction of the signal line I2 from the control device 80. For example, the servo valve 13 includes a spool, an oil passage, a nozzle flapper mechanism, and the like, which will be described later. The valve drive piston displacement meter 15 measures the position of the valve drive piston 12 in the valve drive cylinder 11 and outputs the measured position data to the control device 80.

  A measuring device 20 shown in FIG. 1 is an encoder that measures the rotational speed of the internal combustion engine 1. The measuring device 21 is a crank angle sensor that measures the crank angle of the internal combustion engine 1. The rotational speed information and crank angle information of the internal combustion engine 1 measured by the measuring devices 20 and 21 are output to the control device 80. Here, the number of rotations refers to a rotation speed that is an angle change per unit time at each crank angle.

  The control device 80 is a device that controls the valve driving device 10. As shown in FIG. 1, the control device 80 performs control to start or stop the hydraulic unit 30 via the signal line I1. Further, the control device 80 can control the servo valve 13 via the signal line I2. The control device 80 is connected to the valve drive piston displacement meter 15 and the measurement devices 20 and 21 via signal lines I3, I4, and I5. Next, the control device 80 will be described with reference to FIG.

  The control device 80 illustrated in FIG. 3 includes an input processing circuit 81, an input port 82, a processing unit 90, a storage unit 94, an output port 83, and an output processing circuit 84. The processing unit 90 includes, for example, a CPU (Central Processing Unit) 91, a RAM (Random Access Memory) 92, and a ROM (Read Only Memory) 93. The control device 80 may be accompanied by a display device 85 and an input device 86. A display device 85 and an input device 86 can be connected to the control device 80 as necessary. Further, the control device 80 can operate without the display device 85 and the input device 86.

  The processing unit 90, the storage unit 94, and the input port 82 and the output port 83 are connected via a bus 87, a bus 88, and a bus 89. By the bus 87, the bus 88, and the bus 89, the CPU 91 of the processing unit 90 is configured to exchange control data with the storage unit 94, the input port 82, and the output port 83 and to issue commands to one side. The

  An input processing circuit 81 is connected to the input port 82. For example, measurement data is is connected to the input processing circuit 81. The measurement data is is converted into a signal that can be used by the processing unit 90 by a noise filter, an A / D converter, or the like provided in the input processing circuit 81, and then sent to the processing unit 90 via the input port 82. Thereby, the processing unit 90 can acquire necessary information. The measurement data is is, for example, displacement data, crank angle data, and rotation speed data acquired from the valve drive piston displacement meter 15 and the measurement devices 20 and 21 via signal lines I3, I4, and I5.

  An output processing circuit 84 is connected to the output port 83. The output processing circuit 84 is connected to a display device 85 and an external output terminal. The output processing circuit 84 includes a display device control circuit, a control signal circuit such as a valve drive device, a signal amplification circuit, and the like. The output processing circuit 84 outputs the signal data to the servo valve 13 calculated by the processing unit 90 as a display signal to be displayed on the display device 85 or outputs it as an instruction signal id to be transmitted to the servo valve 13. As the display device 85, for example, a liquid crystal display panel, a CRT (Cathode Ray Tube), or the like can be used. The instruction signal id is transmitted to the servo valve 13 via the signal line I2.

  The storage unit 94 stores a computer program including an operation procedure of the valve gear 100. Here, the storage unit 94 can be configured by a volatile memory such as a RAM, a nonvolatile memory such as a flash memory, a hard disk drive, or a combination thereof.

  The computer program may execute the operation procedure of the valve gear 100 in combination with a computer program already recorded in the processing unit 90. Moreover, this control apparatus 80 may perform the operation | movement procedure of the valve operating apparatus 100 using dedicated hardware instead of a computer program.

  The operation procedure of the valve operating apparatus 100 can also be realized by executing a program prepared in advance on a personal computer, a workstation, or a computer system such as a control computer. The program is recorded on a computer-readable recording medium such as a recording device such as a hard disk, a flexible disk (FD), a ROM, a CD-ROM, an MO, a DVD, or a flash memory, and is read from the recording medium by the computer. Can also be implemented. Here, the “computer system” includes an OS and hardware such as peripheral devices.

  In addition, the “computer-readable recording medium” dynamically stores the program for a short time, such as a communication line when the program is transmitted via a network such as the Internet or a communication line network such as a telephone line. What is held, and what holds a program for a certain period of time, such as volatile memory inside a computer system serving as a server or client in that case, are included. Further, the program may be for realizing a part of the above-described functions, and may be capable of realizing the above-described functions in combination with a program already recorded in the computer system. .

  The control device 80 described above acquires crank angle and rotation speed data from the measurement devices 20 and 21. In the present embodiment, it is assumed that the control device 80 stores a target lift waveform to which a lift amount is originally given for each desired crank angle in the storage unit 94 or the RAM 92. For example, in a 4-stroke engine, one cycle is completed by performing four strokes of intake, compression, expansion, and exhaust while the combustion piston reciprocates twice. The control device 80 generates a target lift waveform for one cycle, and sends a control command as a control signal to the servo valve so that the valve drive piston can be driven with the same drive waveform as the target lift waveform.

  Next, the hydraulic circuit according to the present embodiment will be described. FIG. 4 is an explanatory diagram illustrating an example of a hydraulic circuit according to the first embodiment. The hydraulic circuit 10A shown in FIG. 4 drives the valve drive cylinder 11 of the valve drive device 10 shown in FIG. 2, the valve drive piston 12 movably accommodated in the valve drive cylinder 11, and the valve drive piston 12. The hydraulic circuit with the servo valve 13 is shown.

  The hydraulic circuit 10A includes a valve drive cylinder 11, a valve drive piston 12, a direction switching control valve mechanism 18 having a spool 17, a nozzle flapper mechanism 60, oil passages 41, 42, 43, 44, 45, 46, 47, 48 and 49, throttles 68 and 69, and a pulsation absorber 110 for a hydraulic circuit. The displacement of the spool 17 is measured by a spool displacement meter 19. The spool displacement meter 19 is connected to the control device 80 described above through a signal line I6. Moreover, piping 71, 72, 73, 74, 75, 76, 77 is provided as needed. The oil passages 41, 42, 44, 45, 47, 48, 49 and the pipe 77 are connected to the oil ports 51, 52, 53, 54, 55, 56, 57, 58. The hydraulic circuit pulsation absorber 110 is the hydraulic circuit pulsation absorber according to the first embodiment. The hydraulic circuit 10 </ b> A may be connected to the pulsation absorbing device 130 for hydraulic circuit, the oil port 51, and the oil passage 140 as will be described in the second embodiment to be described later.

  The direction switching control valve mechanism 18 is a three-way switching control valve that can switch in three directions. The direction switching control valve mechanism 18 can switch the oil passages 45 and 48 connected to the oil passage 46 communicating with the valve drive cylinder 11 by the movement of the spool 17. Thereby, the supply target of the hydraulic oil pressure supplied to the oil passage 46 can be switched.

  The nozzle flapper mechanism 60 is a mechanism that changes the pressure by reducing the flow area of the nozzle. As shown in FIG. 4, a nozzle flapper mechanism 60 is interposed in the oil passage 41. The oil passage 41 includes an oil passage 41A on the side of the pipe connection 43a from the nozzle flapper mechanism 60 to the oil passages 42 and 43, and an oil passage 41B on the side of the oil port 51 from the nozzle flapper mechanism 60.

  The control device 80 described above transmits a control signal command, and the nozzle flapper driving mechanism 60 operates in accordance with the control signal command. Along with the operation of the nozzle flapper mechanism 60, the pressure of the oil passage 41A can be changed by the flapper restricting or opening the flow passage area of the nozzle.

  The oil passage 42 shown in FIG. 4 is connected to the hydraulic unit 30 via the oil port 52, and a pilot pressure is applied. The restrictor 68 is an orifice and is a pressure restrictor for adjusting the pilot pressure.

  The oil passage 43 is connected to the oil passage 41 </ b> A and the oil passage 42 by a pipe connection 43 a. The oil passage 43 is also a pressing portion that presses the spool 17 of the direction switching control valve mechanism 18. The oil passage 44 is connected to the hydraulic unit 30 via the oil port 53, and a pilot pressure is applied thereto.

  The oil passage 45 is connected to the hydraulic unit 30 via the oil port 54, and the first hydraulic oil pressure of the valve drive piston 12 is applied thereto. The direction switching control valve mechanism 18 switches the connection between the oil passage 45 and the oil passage 46 according to the position of the spool 17.

  The oil passage 46 connects the direction switching control valve mechanism 18 and the valve drive cylinder upper chamber 11 a of the valve drive cylinder 11. The oil passage 49 is connected to the oil passage 46 through a pipe connection 46 a between the direction switching control valve mechanism 18 and the valve drive cylinder upper chamber 11 a of the valve drive cylinder 11. The oil passage 49 is provided with a pulsation absorber 110 for a hydraulic circuit, and absorbs pulsation generated in the oil passage 46. The oil passage 49 is connected to the hydraulic circuit pulsation absorbing device 130 via the oil port 58. Here, the valve drive cylinder upper chamber 11a is a space in the valve drive cylinder 11, and is a space surrounded by the valve drive piston 12 and the valve drive cylinder 11 on the opposite side of the valve rod 5 shown in FIG. . A pipe 71 is connected to the valve drive cylinder upper chamber 11a, and the pipe 71 acts to vent air as necessary.

  The valve drive cylinder lower chamber 11b is a space surrounded by the valve drive piston 12 and the valve drive cylinder 11 on the valve rod 5 side shown in FIG. The oil passage 47 is connected to the hydraulic unit 30 via the oil port 57, and the second hydraulic oil pressure of the valve drive piston 12 is applied thereto. The oil passage 47 is provided with a throttle 69. The restrictor 69 is an orifice and is a pressure restrictor for adjusting the second hydraulic oil pressure. It is preferable that the second hydraulic oil pressure is set to be smaller than the first hydraulic oil pressure described above by the throttle 69. The oil passage 47 has a pipe connection 47a to which a pipe 72 is connected. The pipe 72 acts to remove air as necessary.

  The oil passage 48 is a return pipeline from the direction switching control valve mechanism 18 and is connected to the oil tank via the oil port 55.

  The pipes 73, 74, 75, 76 and 77 are drain pipes, and moisture is discharged through the oil port 56. The oil ports 51, 52, 53, 54, 55, 56, 57, and 58 are openings that carry oil or moisture that are opened to the servo valve 13.

  Next, the operation of the valve gear according to Embodiment 1 will be described. The control device 80 of the valve gear 100 transmits a control signal command to the servo valve 13. As shown in FIGS. 1 and 2, the control signal command from the control device 80 is transmitted to the servo valve 13 via the signal line I2. In the servo valve 13, the nozzle flapper mechanism 60 operates in response to a control signal command.

  When the nozzle flapper driving mechanism 60 is driven and the pressure of the oil passage 41A is changed by narrowing the nozzle passage area, the pilot pressure is applied to the oil passage 43 without being reduced in the oil passage. The pressure PPB is applied to the oil passage 43. As described above, the pilot pressure is also applied to the oil passage 44. Here, the pressure applied to the oil passage 44 is defined as a pressure PPA.

  In the present embodiment, it is preferable that the throttle 68 is set so that the pressure PPA is substantially half of the pressure PPB when the nozzle flapper mechanism 60 is driven and the flow passage area of the nozzle is most throttled. As a result, when the nozzle flapper mechanism 60 is driven and the pressure passage area of the nozzle is reduced by a predetermined amount or more, the pressure PPB becomes larger than the pressure PPA and the spool 17 moves. When the spool 17 moves, the spool displacement meter 19 reads the displacement of the spool, and the spool displacement meter 19 sends the displacement information of the spool to the control device 80 through the signal line I6.

  As the spool 17 moves, the direction switching control valve mechanism 18 connects the oil passage 45 and the oil passage 46. As a result, the valve drive cylinder upper chamber 11a becomes the first hydraulic oil pressure and becomes larger than the second hydraulic oil pressure of the valve drive cylinder lower chamber 11b, so that the valve drive piston 12 of the valve rod shown in FIG. Will move in the direction. The displacement of the valve drive piston 12 is measured by the valve drive piston displacement meter 15 shown in FIG. 2, and the valve drive piston displacement meter 15 sends piston displacement information to the control device 80 through the signal line I3.

  Conversely, when the nozzle flapper driving mechanism 60 is driven and the pressure of the oil passage 41A is changed by opening the restriction of the nozzle passage area, the pilot pressure of the oil passage 42 is reduced. For this reason, the pressure applied to the oil passage 43 is also reduced. As a result, the PPB applied to the oil passage 43 becomes smaller than the pressure PPA applied to the oil passage 44.

  That is, when the nozzle flapper driving mechanism 60 is driven and the restriction of the nozzle flow path area is opened more than a predetermined pressure, the pressure PPA becomes larger than the pressure PPB and the spool 17 moves. When the spool 17 moves, the spool displacement meter 19 reads the displacement of the spool, and the spool displacement meter 19 sends the displacement information of the spool to the control device 80 through the signal line I6.

  As the spool 17 moves, the direction switching control valve mechanism 18 switches the connection between the oil passage 45 and the oil passage 46 to the connection between the oil passage 48 and the oil passage 46. As a result, the valve drive cylinder upper chamber 11a becomes the pressure of the return line, and becomes smaller than the second hydraulic oil pressure in the valve drive cylinder lower chamber 11b, so that the valve drive piston 12 is the reverse of the valve rod shown in FIG. Will move in the direction. The displacement of the valve drive piston 12 is measured by the valve drive piston displacement meter 15 shown in FIG. 2, and the valve drive piston displacement meter 15 sends piston displacement information to the control device 80 through the signal line I3.

  As described above, the valve operating apparatus for an internal combustion engine according to the first embodiment operates in response to a control signal, and changes the pressure by reducing the flow area of the nozzle, and the operation of the nozzle flapper mechanism. A direction switching control valve for switching the supply target of the hydraulic oil pressure, and a reciprocating motion in the valve drive cylinder according to the supply target of the hydraulic oil pressure switched by the direction switching control valve, so that the exhaust valve and the intake valve of the internal combustion engine A valve drive piston capable of driving at least one of the valves, and when the pressure is changed by narrowing the flow area of the nozzle of the nozzle flapper mechanism, the direction switching control valve is switched according to the change in the pressure. The supply target of the hydraulic oil pressure changes, and the valve drive piston protrudes from the valve drive cylinder according to the supply target of the hydraulic oil pressure. Conversely, when the pressure is changed by opening the nozzle flow area of the nozzle flapper mechanism, the supply target of the hydraulic oil pressure is changed by the direction switching control valve, and the supply target of the hydraulic oil pressure is changed. Then, the valve drive piston moves in a direction (contracted direction) in which it is stored in the valve drive cylinder.

  As a result, a hydraulic flow is generated in the oil passage 46 connecting the direction switching control valve mechanism 18 and the valve drive cylinder upper chamber 11a of the valve drive cylinder 11. When unnecessary pulsation is generated in the oil passage 46, unnecessary vibration is added to the operation of the valve drive piston, which is not desirable. Further, in order to switch the valve drive piston quickly, it is necessary to absorb the pulsation quickly. For this reason, as shown in FIG. 4, in the hydraulic circuit 10 </ b> A of the first embodiment, the hydraulic circuit 46 is connected to the oil passage 46 connecting the direction switching control valve mechanism 18 and the valve drive cylinder upper chamber 11 a of the valve drive cylinder 11. A pulsation absorbing device 110 is connected to absorb pulsation. By providing the hydraulic circuit pulsation absorbing device 110 in the servo valve 13 and the valve drive cylinder 11, the distance from the oil passage 46 to the hydraulic circuit pulsation absorbing device 110 is shortened, and the pulsation can be absorbed quickly.

  FIG. 5 is a schematic diagram illustrating the pulsation absorbing device for a hydraulic circuit according to the first embodiment. The pulsation absorbing device 110 for a hydraulic circuit shown in FIG. 5 includes an air chamber (gas chamber) 111, an air supply path 112, an oil chamber 113, a flexible membrane member 115, a flexible membrane deformation suppressing member 120, Is included. The pulsation absorber 110 for the hydraulic circuit is disposed in the vicinity of the outer side surface 11A that is the boundary between the valve drive cylinder 11 and the servo valve 13 shown in FIG.

  An air chamber (gas chamber) 111 shown in FIG. 5 is a space formed in the valve drive cylinder 11. For example, this space is a cylindrical space. The air chamber (gas chamber) 111 can contain a gas such as air or nitrogen. The air supply path 112 is an air supply hole for supplying gas to the air chamber (gas chamber) 111. The oil chamber 113 is a space formed in the servo valve 13. It is connected to the oil passage 49 and filled with oil. The oil chamber 113 is, for example, a cylindrical space. The air chamber (gas chamber) 111 may be a space formed in the servo valve 13, and the oil chamber 113 may be a space formed in the drive cylinder 11.

  The flexible membrane member 115 is a separator that separates the air chamber (gas chamber) 111 and the oil chamber 113, and has a plate-like flexible membrane 116. At the periphery of the flexible membrane member 115, the valve drive cylinder 11 is in contact with the flexible membrane air chamber side surface 116A, and the servo valve 13 is fixed in contact with the flexible membrane oil chamber side surface 116B. For example, the flexible film 116 is preferably formed of an oil-resistant elastomer such as nitrile butadiene rubber (NBR). As shown in FIG. 5, the flexible membrane member 115 is sandwiched and fixed between the valve drive cylinder 11 and the servo valve 13. Since a flexible membrane member 115 is provided at the boundary between the valve drive cylinder 11 and the servo valve 13 and the air chamber (gas chamber) 111 and the oil chamber 113 are arranged via the flexible membrane member 115, space saving is achieved. The valve operating device can be made small.

  FIG. 6 is a schematic diagram illustrating the flexible membrane member according to the first embodiment. The flexible membrane member 115 is sized according to the shape of the air chamber (gas chamber) 111 and the oil chamber 113 in order to make the air chamber (gas chamber) 111 and the oil chamber 113 oil-tight. For example, as shown in FIG. 6, since the air chamber (gas chamber) 111 and the oil chamber 113 are cylindrical, a disk shape larger than the larger diameter of the air chamber (gas chamber) 111 and the oil chamber 113 is formed. It has a shape.

  As shown in FIGS. 5 and 6, the flexible membrane member 115 preferably includes a hollow disk-shaped reinforcing ring 117 in order to reinforce the strength of the flexible membrane 116. The reinforcing ring 117 is formed of a metal material having an antirust effect such as stainless steel, and is preferably covered with the material of the flexible film 116.

  FIG. 7 is a schematic diagram illustrating the flexible membrane deformation suppressing member according to the first embodiment. The flexible film deformation suppressing member 120 is formed of a material having a gap inside, for example, a foamed resin such as polyurethane. As shown in FIG. 7, the flexible membrane deformation suppressing member 120 preferably has a shape similar to the space in the air chamber 111. For example, the flexible film deformation suppressing member 120 has a cylindrical shape. The flexible membrane deformation suppressing member 120 is a distance between the flexible membrane side surface 120A that contacts the flexible membrane air chamber side surface 116A of the flexible membrane member 115 and the air chamber rear wall surface 120B that contacts the air chamber rear wall 111A. Is larger than the distance between the flexible membrane air chamber side surface 116A and the air chamber rear wall 111A before the flexible membrane member 115 is deformed. For this reason, the flexible membrane deformation suppressing member 120 applies a pressing force to the flexible membrane member 115. The flexible film deformation suppressing member 120 may be formed by filling a material having an indeterminate shape and a void inside, for example, a foamed resin such as polyurethane.

  As described above, the pulsation absorbing device for a hydraulic circuit according to the first embodiment has a plate shape that separates the oil chamber connected to the oil passage of the hydraulic circuit, the air chamber containing gas, and the air chamber and the oil chamber. A flexible membrane member, and a flexible membrane deformation suppressing member that is in the air chamber and that is in contact with the flexible membrane member and suppresses deformation of the flexible membrane member.

  Here, the fluctuation of the hydraulic pressure transmitted to the oil chamber first causes deformation of the flexible membrane member and compresses the gas in the air chamber. The volume of gas can be changed according to the change of pressure, but there is an allowable range for the deformation of the flexible membrane member. The hydraulic circuit pulsation absorbing device according to the first embodiment is a small hydraulic circuit pulsation absorbing device because the air chamber and the oil chamber are separated using a plate-like flexible membrane member. On the other hand, the plate-like flexible membrane member has a narrow allowable range of deformation. Therefore, the pulsation absorbing device for a hydraulic circuit according to the first embodiment is provided by a flexible membrane deformation suppressing member that is in the air chamber and that is in contact with the flexible membrane member and suppresses deformation of the flexible membrane member. Excessive deformation of the plate-like flexible membrane member is suppressed. Thereby, the possibility that the flexible membrane member cannot withstand the fluctuation of the hydraulic pressure transmitted to the oil chamber can be reduced.

  In the pulsation absorbing device for a hydraulic circuit according to the first embodiment, the flexible membrane deformation suppressing member is preferably made of a material having a gap inside. The material with voids inside contains gas, which can change volume in response to changes in pressure. For this reason, pulsation is absorbed. Moreover, the flexible film | membrane deformation | transformation suppression member can suppress the excessive deformation | transformation of a plate-shaped flexible film | membrane member. The material having voids inside is more preferably a foamed resin.

(Embodiment 2)
FIG. 8 is a schematic diagram illustrating a pulsation absorbing device for a hydraulic circuit according to the second embodiment. The valve operating test apparatus according to the present embodiment is the same as that of the first embodiment, but is characterized by the hydraulic circuit pulsation absorbing device 130 described above in the first embodiment. In the following description, the same components as those described in the first embodiment are denoted by the same reference numerals, and redundant descriptions are omitted.

  As shown in FIG. 8, the hydraulic circuit pulsation absorber 130 includes an air chamber (gas chamber) 131, an air supply path 132, an oil chamber 133, a flexible membrane member 115, and flexible membrane deformation suppression. Member 120. The hydraulic circuit pulsation absorbing device 130 is connected to the oil passage 46 in parallel with the hydraulic circuit pulsation absorbing device 110 shown in FIG. 4 to absorb the pulsation of the oil passage 46.

  An air chamber 131 shown in FIG. 8 is a space formed in the block lid 152. For example, this space is a cylindrical space. The air chamber 131 can contain a gas such as air or nitrogen. The air supply path 132 is an air supply hole for supplying gas to the air chamber 131. The oil chamber 133 is a space formed in the block 153. The oil chamber 133 is connected to an oil passage 140 shown in FIG. 4 and an oil passage 140 connected via an oil port 58, and is filled with oil. Here, the oil chambers 133 are connected with oil passages 140a, 140b, 140x, which are similarly connected from other valve gears, and a plurality of oil passages having the same number of cylinders as the engine valves, and are filled with oil. That is, the oil chamber 133 can be connected to the plurality of oil passages 140, 140a, 140b, 140x of the hydraulic circuit, and the hydraulic circuit pulsation absorbing device 130 for absorbing pulsation can be made common. Thereby, the size of the entire system can be reduced. The oil chamber 133 is, for example, a cylindrical space. The oil passage 134 is connected to a return flow path to the hydraulic unit 30.

  Since the flexible membrane member 115 is the same as that of the first embodiment described above, description thereof is omitted. At the periphery of the flexible membrane member 115, the block lid 152 is in contact with the flexible membrane air chamber side surface 116A, and the block 153 is fixed in contact with the flexible membrane oil chamber side surface 116B. Similar to the first embodiment, the flexible membrane deformation suppressing member 120 has a cylindrical shape. In the flexible membrane deformation suppressing member 120 shown in FIG. 7, the flexible membrane side surface 120A of the flexible membrane member 115 in contact with the flexible membrane air chamber side surface 116A, and the air chamber rear wall surface in contact with the air chamber rear wall 131A. The distance from 120B is larger than the distance between the flexible membrane air chamber side surface 116A and the air chamber rear wall 131A shown in FIG. 8 in a state before the flexible membrane member 115 is deformed. For this reason, the flexible membrane deformation suppressing member 120 applies a pressing force to the flexible membrane member 115. The flexible film deformation suppressing member 120 may be formed by filling a material having an indeterminate shape and a void inside, for example, a foamed resin such as polyurethane.

  As described above, the pulsation absorber for a hydraulic circuit according to the second embodiment is an oil chamber connected to the oil passage of the hydraulic circuit, an air chamber containing gas, and a plate shape that separates the air chamber and the oil chamber. A flexible membrane deformation restraining member that resides in the air chamber and suppresses deformation of the flexible membrane member in contact with the flexible membrane member, The oil chamber is connected to a plurality of oil passages of a hydraulic circuit. Thereby, the size of the entire system can be reduced.

(Embodiment 3)
FIG. 9 is a schematic view showing a flexible membrane deformation suppressing member according to the third embodiment. The pulsation absorbing device for a hydraulic circuit according to the present embodiment is the same as that of the first or second embodiment, and the flexible film deformation suppressing member 120 described in the first or second embodiment is used as a volume fluctuation suppressing mechanism. It is characterized by the replacement. In the following description, the same components as those described in the first embodiment or the second embodiment are denoted by the same reference numerals, and redundant description is omitted.

  A flexible membrane deformation suppressing member 121 shown in FIG. 9 includes a bellows-like rubber 125 that is an elastic member, and stoppers 127 and 128 that are locking members that suppress deformation of the bellows-like rubber 125. It is formed with. In the flexible membrane deformation suppressing member 121, it is desirable that positioning members 122 and 123 are fixed to both ends of the bellows-like rubber 125 by a plurality of attachment members 150 for positioning the bellows-like rubber 125. Moreover, it is preferable that the flexible film | membrane deformation | transformation suppression member 121 fits in the space which the air chamber 111 of FIG. 5 or the air chamber 131 of FIG. For example, the flexible membrane deformation suppressing member 120 has a shape that fits in a cylindrical shape.

  The bellows-like rubber 125 is a hollow, substantially cylindrical bellows-like elastic member, and can contain gas in the hollow portion. The bellows-like rubber 125 can be deformed, and the distance between the positioning members 122 and 123 can be reduced. When the distance between the positioning members 122 and 123 is reduced, a pressing force for returning the distance between the positioning members 122 and 123 acts. When a force that greatly reduces the distance between the positioning members 122 and 123 is applied, the distance between the stoppers 127 and 128 is also reduced, and deformation of the bellows-like rubber 125 can be suppressed.

  The flexible membrane deformation suppressing member 121 shown in FIG. 9 includes a side surface 123A in contact with the flexible membrane air chamber side surface 116A of the flexible membrane member 115 shown in FIG. 5 or FIG. 8, and an air chamber rear wall 111A (131A). The distance between the side surface 122A and the side surface 122A is larger than the distance between the flexible membrane air chamber side surface 116A and the air chamber rear wall 111A (131A) before the flexible membrane member 115 is deformed. It is preferable that the membrane deformation suppressing member 120 applies a pressing force to the flexible membrane member 115.

  As described above, the pulsation absorber for a hydraulic circuit according to the third embodiment is an oil chamber connected to the oil passage of the hydraulic circuit, an air chamber containing gas, and a plate shape that separates the air chamber and the oil chamber. A flexible membrane deformation restraining member that resides in the air chamber and suppresses deformation of the flexible membrane member in contact with the flexible membrane member, The flexible membrane deformation suppressing member includes a bellows-like elastic member and a locking member that suppresses deformation of the bellows-like elastic member. The bellows-like elastic member contains a gas, and the gas can change its volume in accordance with a change in pressure. For this reason, pulsation is absorbed. Moreover, the flexible film | membrane deformation | transformation suppression member can suppress the excessive deformation | transformation of a plate-shaped flexible film | membrane member.

  As described above, the embodiment includes a valve drive piston capable of driving an exhaust valve or an intake valve of an internal combustion engine, and an oil passage of the hydraulic circuit connected to a valve drive cylinder in which the valve drive piston reciprocates. The hydraulic circuit pulsation absorbers 1, 2, and 3 absorb the pulsation of the oil passage of the hydraulic circuit connected to the valve drive cylinder.

  Thereby, the pulsation of the oil passage is absorbed, and the possibility that unnecessary vibration is added to the operation of the valve drive piston is reduced. As a result, the valve operating device for the internal combustion engine having the pulsation absorbing device for hydraulic circuit in which the durability of the flexible membrane member is enhanced.

  Note that the valve operating apparatus and the valve operating driving method described above are also suitable for a testing machine that opens and closes an intake valve or an exhaust valve of an internal combustion engine. The internal combustion engine of the present embodiment preferably drives the cylinder block, the combustion piston that moves up and down in the cylinder block, the exhaust valve and the intake valve, and the exhaust valve and the intake valve. Thereby, it is possible to contribute to the reduction of NOx and unburned HC emissions and the reduction of carbon dioxide emissions by clean exhaust and improved fuel efficiency.

DESCRIPTION OF SYMBOLS 1 Internal combustion engine 2 Piston for combustion 3 Cylinder block 4a Exhaust valve 4b Intake valve 5 Valve rod 6 Valve spring 7 Crankshaft 8 Connecting rod 9 Crankcase 10 Valve drive device 11 Valve drive cylinder 11a Valve drive cylinder upper chamber 11b Valve drive cylinder bottom Chamber 12 Valve drive piston 13 Servo valve 15 Valve drive piston displacement meter 17 Spool 18 Direction switching control valve mechanism 19 Spool displacement meter 20, 21 Measuring device 30 Hydraulic unit 41, 42, 43, 44, 45, 46, 47, 48, 49 Oil path 60 Nozzle flapper mechanism 80 Control device 100 Valve device 110, 130 Pulsation absorber for hydraulic circuit 111, 131 Air chamber 113, 133 Oil chamber 115 Flexible membrane member 120, 121 Flexible membrane deformation suppression member

Claims (5)

An oil chamber connected to the oil passage of the hydraulic circuit;
An air chamber containing gas;
A plate-like flexible membrane member separating the air chamber and the oil chamber;
A flexible membrane deformation restraining member that resides in the air chamber and restrains the deformation of the flexible membrane member in contact with the flexible membrane member;
A pulsation absorbing device for a hydraulic circuit, comprising:   The pulsation absorbing device for a hydraulic circuit according to claim 1, wherein the flexible membrane deformation suppressing member is made of a material having a gap inside.   The pulsation absorbing device for a hydraulic circuit according to claim 1, wherein the flexible membrane deformation suppressing member includes a bellows-like elastic member and a locking member that suppresses deformation of the bellows-like elastic member.   The pulsation absorbing device for a hydraulic circuit according to any one of claims 1 to 3, wherein the oil chamber is connected to a plurality of oil passages of the hydraulic circuit. A valve drive piston capable of driving an exhaust valve or an intake valve of an internal combustion engine, and an oil passage of the hydraulic circuit connected to a valve drive cylinder in which the valve drive piston reciprocates,
5. A valve for an internal combustion engine, wherein the pulsation absorbing device for a hydraulic circuit according to any one of claims 1 to 4 absorbs pulsation of an oil passage of the hydraulic circuit connected to the inside of the valve drive cylinder. apparatus.

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