JP2011153593A - Control device of power transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control device of a power transmission which can effectively utilize pressure of exhaust gas produced in an internal combustion engine. <P>SOLUTION: A control device of a power transmission which is equipped with a movable member for controlling a power transmission state of a power transmission and a pressure chamber for generating power applied to the movable member, consists of an internal combustion engine 2 for producing power by burning fuel and a pressure transmission mechanism 22A for transmitting pressure of exhaust gas produced in the internal combustion engine 2 to a pressure chamber 18. The pressure transmission mechanism 22A is constituted to make the speed of exhaust gas in the downstream pipe line 25 faster than that in the upstream pipe line 23, and equipped with bypass pipe lines 26, 28 for connecting the upstream pipe line 23 and downstream pipe line 25. The exhaust gas pressure of the upstream pipe line 23 is transmitted to the pressure chamber 18 via the bypass pipe line 26 by pressure difference between the upstream pipe line 23 and downstream pipe line 25. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a device that controls a power transmission state in a device that transmits power, and more particularly to a control device that controls a power transmission state by changing a pressure to be applied.

  Patent Document 1 describes an example of a vehicle configured to control the power transmission state of a power transmission device by controlling the operation of a movable member by the pressure of a fluid. The vehicle described in Patent Document 1 is configured to increase or decrease the torque output from the engine by a transmission and output the torque to driving wheels. The engine has the same configuration as a conventionally known internal combustion engine for a vehicle, and generates mechanical power by burning a mixture of intake air and fuel adjusted by a throttle valve inside the cylinder. It is a heat engine. Therefore, exhaust gas with high pressure is generated by the combustion of the fuel, and the exhaust gas is discharged outside the vehicle through the exhaust pipe.

  On the other hand, the transmission described in Patent Document 1 has a drive shaft and a driven shaft, and is provided with a drive pulley that rotates integrally with the drive shaft. The drive pulley includes a first movable disk that can move in the axial direction and a first fixed disk that does not move in the axial direction. A first engagement groove is formed between the first movable disk and the first fixed disk. Further, a backup disk is fixed to the drive shaft, and a spherical weight is disposed between the first movable disk and the backup disk. This weight is configured to move outward in the radial direction of the drive shaft by centrifugal force.

  Furthermore, a driven pulley that rotates integrally with the driven shaft is provided, and the driven pulley includes a second movable disk that is movable in the axial direction and a second fixed disk that is not movable in the axial direction. Yes. A second engagement groove is formed between the second movable disk and the second fixed disk. In addition, a spring that pushes the second movable disk toward the second fixed disk is provided. Further, a negative pressure introduction chamber is formed in the drive pulley, and the negative pressure introduction chamber is connected downstream of the throttle valve in the intake pipe of the engine, so that the negative pressure in the intake pipe acts on the negative pressure introduction chamber. Is configured to do. A V-belt is wound around the drive pulley and the driven pulley configured as described above.

  In the transmission described in Patent Document 1, the force by which the spring pushes the second movable disk when the drive shaft rotates at a relatively low speed causes the weight to move outward, causing the first movable disk to move. Greater than pressing force. For this reason, the width of the second engagement groove in the driven pulley is reduced, the width of the first engagement groove in the drive pulley is increased, and the transmission gear ratio is relatively increased. On the other hand, when the drive shaft rotates at a relatively high speed, the force that pushes the first movable disk as the weight tends to move outward becomes larger than the force that the spring pushes the second movable disk. Then, the width of the first engagement groove in the drive pulley is narrowed, and the width of the second engagement groove in the driven pulley is increased. In this way, the gear ratio of the transmission becomes relatively small.

  Furthermore, in the vehicle described in Patent Document 1, when the rider tries to decelerate the vehicle while the vehicle is traveling and the throttle valve of the engine is closed to the fully closed state, an engine braking force is generated. In parallel with this action, the negative pressure of the intake pipe is introduced into the negative pressure introduction chamber. Then, this negative pressure causes the weight to move inward in the radial direction against the centrifugal force, and the force for pushing the first movable disc of the drive pulley toward the first fixed disc is reduced. The force by which the spring pushes the second movable disk becomes larger than the force by which the weight pushes the first movable disk, the width of the second engagement groove in the driven pulley is narrowed, and the first engagement in the drive pulley is reduced. The width of the groove is enlarged. In this way, the V-belt wrapping radius in the drive pulley is relatively small, and the transmission gear ratio is relatively large. As a result, the engine braking force is increased. Note that a hydraulic control device for a transmission in a vehicle is described in Patent Document 2, and a control device for a belt-type continuously variable transmission is described in Patent Document 3. Further, as a technology using fluid energy, there is an engine energy recovery device described in Patent Document 4.

Japanese Patent Laid-Open No. 11-2316 JP-A-61-2228149 JP 62-127550 A JP 2007-85440 A

  In the vehicle described in Patent Document 1, when the vehicle is decelerating, the intake pipe negative pressure of the internal combustion engine is guided to the negative pressure introduction chamber of the transmission to change the transmission gear ratio. . That is, the intake pipe negative pressure of the internal combustion engine is used for control for increasing the engine braking force when the vehicle is decelerated. However, in the vehicle described in Patent Document 1, exhaust gas generated when fuel is burned is released into the atmosphere via an exhaust pipe. Conventionally, no consideration has been given to using the energy of the exhaust gas, particularly the pressure of the exhaust gas, and there is still room for improvement in effectively using the energy of the exhaust gas.

  The present invention has been made paying attention to the above technical problem, and is a power transmission device capable of improving energy efficiency by effectively using the pressure of exhaust gas generated when fuel is burned in an internal combustion engine. An object of the present invention is to provide a control device.

  In order to achieve the above object, the invention of claim 1 is directed to a power transmission device to which power is input, a movable member movably provided to control the power transmission state of the power transmission device, An internal combustion engine for converting the thermal energy generated when the fuel is burned into kinetic energy and outputting the kinetic energy And a pressure transmission mechanism for transmitting exhaust gas generated when the fuel is burned in the internal combustion engine and transmitting the pressure of the exhaust gas to the pressure chamber, and the pressure transmission mechanism is relative to the flow direction of the exhaust gas. An upstream pipeline arranged upstream, a downstream pipeline arranged downstream of the upstream pipeline in the flow direction of the exhaust gas, and a flow rate of the exhaust gas faster than the upstream pipeline, and the upstream pipeline And downstream pipes A bypass pipe to be connected, and based on the difference between the flow rate of the exhaust gas in the upstream pipeline and the flow rate of the exhaust gas in the downstream pipeline, the pressure of the exhaust gas in the upstream pipeline and the exhaust gas in the downstream pipeline As a result of the pressure difference, the exhaust gas pressure in the bypass line is transferred to the pressure chamber in the process where the exhaust gas in the upstream line merges with the downstream line via the bypass line. It is comprised so that it may be comprised.

  According to a second aspect of the present invention, in addition to the configuration of the first aspect, the cross-sectional area in a plane perpendicular to the flow direction of the exhaust gas is such that the downstream pipe is narrower than the upstream pipe. A control device for a power transmission device, characterized in that the downstream pipe is faster than the upstream pipe.

  According to a third aspect of the present invention, in addition to the configuration of the second aspect, the cross-sectional area in a plane perpendicular to the flow direction of the exhaust gas is disposed downstream of the downstream pipe in the flow direction of the exhaust gas. A control device for a power transmission device, wherein a connection pipe wider than the downstream pipe is provided.

  According to the first aspect of the present invention, when the exhaust gas generated when the fuel is burned in the internal combustion engine is discharged to the pressure transmission mechanism, the flow rate of the exhaust gas in the downstream pipe is higher than the flow speed of the exhaust gas in the upstream pipe. It becomes faster and the pressure in the downstream line is lower than the pressure in the upstream line. Due to this pressure difference, the pressure of the exhaust gas in the bypass pipeline is transmitted to the pressure chamber in the process in which the exhaust gas in the upstream pipeline merges with the downstream pipeline via the bypass pipeline. By moving the movable member with the pressure in the pressure chamber, the power transmission state of the power transmission device can be controlled. Therefore, the pressure of the exhaust gas discharged from the internal combustion engine can be used effectively.

  According to the invention of claim 2, in addition to obtaining the same effect as that of the invention of claim 1, since the cross-sectional area of the downstream pipe is narrower than the cross-sectional area of the upstream pipe, the flow rate of the exhaust gas is higher than that of the upstream pipe. Will also be faster in downstream pipelines.

  According to the invention of claim 3, in addition to obtaining the same effect as that of the invention of claim 2, when the exhaust gas reaches the connecting pipe from the downstream pipe, the flow resistance is lowered, so that the exhaust gas is discharged from the internal combustion engine. It is possible to suppress an increase in back pressure when

It is a schematic diagram which shows the specific example which used the control apparatus of the power transmission device in this invention for control of the continuously variable transmission of a vehicle. It is a schematic diagram which shows the other structural example of the pressure transmission mechanism shown by FIG.

  The control device for the power transmission device according to the present invention is a device for controlling the power transmission state by transmitting the pressure of the exhaust gas generated in the internal combustion engine to the pressure chamber. In the power transmission state of the power transmission device according to the present invention, the gear ratio between the rotating members constituting the power transmission device, the torque capacity between the rotating members constituting the power transmission device, and the one constituting the power transmission device The rotation direction of the other rotation member with respect to the other rotation member is included. Specific examples of the present invention will be described below with reference to the drawings.

  A specific example in which the present invention is used as a control device for a continuously variable transmission of a vehicle will be described with reference to FIG. The vehicle 1 shown in FIG. 1 has an engine 2. This engine 2 is configured in the same manner as a conventionally known engine, and is a prime mover that converts thermal energy generated when fuel is burned into kinetic energy and outputs it, and a mixture of fuel and air is a combustion chamber. The exhaust gas that is combusted (not shown) and generated during combustion of the air-fuel mixture is discharged to the exhaust pipe 9 via the exhaust valve. Further, the exhaust pipe 9 is connected to an exhaust purification catalyst 11. The exhaust purification catalyst 11 is the same as a conventionally known catalyst, and includes contaminants such as carbon monoxide (CO), hydrocarbons (HC) contained in the exhaust gas discharged from the engine 2 to the exhaust pipe 9. ), Nitrogen oxide (NOx) and the like are reduced to purify the exhaust gas.

  On the other hand, the vehicle 1 has driving wheels (not shown), and is configured such that torque is transmitted to the driving wheels to generate driving force. In this specific example, the motive power of the engine 2 is configured to be transmitted to driving wheels, and a continuously variable transmission 12 that forms part of a power transmission path from the engine 2 to the driving wheels is provided. ing. The continuously variable transmission 12 includes a primary pulley (drive pulley) 13 and a secondary pulley (driven pulley) 14, and a belt type continuously variable transmission configured by winding a belt 15 around the primary pulley 13 and the secondary pulley 14. This is a transmission that can change the ratio between the rotation speed of the primary pulley 13 and the rotation speed of the secondary pulley 14, that is, the gear ratio steplessly (continuously).

  The primary pulley 13 is provided so as to be rotatable about a rotation center axis, and the primary pulley 13 is provided with a fixed piece 16 that cannot move in a direction along the rotation center axis, and a rotation center axis. A movable piece 17 configured to be movable in the direction is provided, and a belt 15 is wound between the fixed piece 16 and the movable piece 17. In addition, a primary pressure chamber 18 is formed that generates a thrust (pressing force) in a direction in which the movable piece 17 approaches the fixed piece 16 along the rotation center axis. The primary pressure chamber 18 is constituted by a cylindrical cylinder. The pressure in the primary pressure chamber 18 may be directly transmitted to the movable piece 17, or the pressure in the primary pressure chamber 18 is transmitted to the movable piece 17 through a piston (not shown). You may be comprised so that.

  On the other hand, the secondary pulley 14 is provided so as to be rotatable about the rotation center axis, and the secondary pulley 14 is arranged along the rotation center axis and a fixed piece 19 that cannot move in the direction along the rotation center axis. The movable piece 20 is configured to be movable in a predetermined direction, and the belt 15 is wound between the fixed piece 19 and the movable piece 20. In addition, a secondary pressure chamber 21 is provided that generates a force that moves the movable piece 20 closer to the fixed piece 19 along the rotation center axis. The secondary pressure chamber 21 is provided with a compression spring that applies a preload to the movable piece 20 and a fluid that can change the force applied to the fixed piece 20. That is, by controlling the pressure of the fluid in the secondary pressure chamber 21, it is possible to control the force in the direction in which the movable piece 20 approaches the fixed piece 19.

  Next, a mechanism for transmitting pressure to the primary pressure chamber 18 will be described. In this specific example, a pressure transmission mechanism 22 </ b> A that transmits the pressure of the high-pressure exhaust gas generated in the engine 2 to the primary pressure chamber 18 is provided. The pressure transmission mechanism 22A is provided in an exhaust gas passage route from the exhaust pipe 9 to the exhaust purification catalyst 11. The configuration of the pressure transmission mechanism 22A will be specifically described. The first pipeline 23 connected to the exhaust port, the second pipeline 24 connected to the first pipeline 23, and the second pipeline 24 And a third conduit 25 connected to the exhaust purification catalyst 11. The first pipe line 23, the second pipe line 24, and the third pipe line 25 have a circular cross-sectional shape in a plane perpendicular to the flow direction of the exhaust gas. The inner diameter of the first conduit 23 is configured to be constant in the direction of exhaust gas flow, and the inner diameter of the third conduit 25 is configured to be constant in the direction of exhaust gas flow.

  Further, the inner diameter of the first conduit 23 is configured to be larger than the inner diameter of the third conduit 25. For this reason, the cross-sectional area A1 of the 1st pipe line 23 is larger than the cross-sectional area A2 of the 3rd pipe line 25 in the plane perpendicular | vertical with respect to the distribution direction of waste gas. In the plane cross section along the flow direction of the exhaust gas, the second conduit 24 is tapered so that the inner diameter becomes smaller as the second conduit 24 approaches the third conduit 25 from the first conduit 23. That is, the inner diameter of the second conduit 24 is narrowed along the flow direction of the exhaust gas. Thus, since the cross-sectional area A1 of the first pipe line 23 is larger than the cross-sectional area A2 of the third pipe line 25, the exhaust gas passes from the first pipe line 23 via the second pipe line 24 to the third pipe line 25. , The flow rate of the exhaust gas in the third pipeline 25 becomes faster than the flow rate of the exhaust gas in the first pipeline 23, and the pressure of the third pipeline 25 becomes lower than the pressure p1 of the first pipeline 23.

  Furthermore, a branch pipe 26 is provided, one end of which is connected to the first pipe 23 and the other end of which is connected to the primary pressure chamber 18. The branch pipe 26 is a path for supplying the pressure of the exhaust gas discharged from the engine 2 to the primary pressure chamber 18. The branch pipe 26 is provided with an orifice 27. The orifice 27 is a mechanism for reducing the flow rate of the exhaust gas flowing from the first pipe line 23 into the branch pipe line 26, and the orifice 27 is configured to have a smaller cross-sectional area than other portions in the branch pipe line 26. ing. Further, a return line 28 is provided between the orifice 27 and the primary pressure chamber 18 in the branch line 26 and connecting the third line 25. The return pipe 28 constitutes a path for returning the exhaust gas flowing into the branch pipe 26 from the first pipe 23 to the third pipe 25.

  Further, a throttle valve 29 is provided in the return line 28. The throttle valve 29 is a pressure control valve that controls the pressure of the branch pipe 26 by adjusting the cross-sectional area of the return pipe 28. Since the exhaust gas passes through the first pipe 23, the third pipe 25, the branch pipe 26, and the return pipe 28, these pipes are formed using metal pipes having excellent heat resistance and durability. be able to. In addition, you may form the 1st pipe line 23, the 2nd pipe line 24, and the 3rd pipe line 25 by changing the design of the internal diameter of a part of the exhaust pipe 9 originally provided.

  On the other hand, a mechanism for transmitting pressure to the secondary pressure chamber 21 will be described. In this specific example, a pressure transmission mechanism 22 </ b> B that transmits the pressure of the high-pressure exhaust gas generated in the engine 2 to the secondary pressure chamber 21 is provided. The configuration of the pressure transmission mechanism 22B is the same as that of the pressure transmission mechanism 22A, and is different from the pressure transmission mechanism 22A in that the exhaust pipe 9 and the secondary pressure chamber 21 are connected. That is, the first conduit 23 of the pressure transmission mechanism 22 </ b> B is connected to the exhaust pipe 9, and the branch conduit 26 is connected to the secondary pressure chamber 21. Other configurations of the pressure transmission mechanism 22B are the same as those of the pressure transmission mechanism 22A. Thus, in the specific example of FIG. 1, the exhaust pipe 9 is branched in two directions, and the pressure transmission mechanism 22A and the pressure transmission mechanism 22B are arranged in parallel in the exhaust gas discharge path.

  A control unit (electronic control unit) 30 for controlling the engine 2 and the continuously variable transmission 12 is provided. The control unit 30 includes various information on the vehicle 1 such as accelerator opening, vehicle speed, engine speed, input speed and output speed of the continuously variable transmission 12, pressure in the primary pressure chamber 18, and secondary pressure chamber 21. A sensor or switch signal for detecting the pressure of the sensor is input. The control unit 30 outputs a signal for controlling the engine torque and a signal for controlling the gear ratio and torque capacity of the continuously variable transmission 12.

The operation and control of the engine 1 will be described. Thermal energy when the air-fuel mixture burns in the combustion chamber is converted into kinetic energy, and torque is output from the crankshaft. This engine torque is transmitted to the drive wheels via the continuously variable transmission 12. The exhaust gas generated in the combustion chamber reaches the first pipeline 23 of the pressure transmission mechanism 22A via the exhaust pipe 9. When the exhaust gas flows from the first pipe 23 to the third pipe 25 via the second pipe 24, the flow rate of the exhaust gas in the third pipe 25 is higher than the flow speed of the exhaust gas in the first pipe 23. As a result, the pressure in the third pipe 25 becomes lower than the pressure p1 in the first pipe 23. This is clear from Bernoulli's theorem. This Bernoulli's theorem is a law of conservation of energy that holds along the flow of fluid, and the behavior of the fluid can be expressed by the following equation.
(1/2) · ρv ² + ρgz + p = constant In the above equation, v is the flow velocity of the exhaust gas, g is the acceleration of gravity, z is the height, p is the pressure, and ρ is the density of the exhaust gas. The exhaust gas flowing into the third pipeline 25 is purified by the exhaust purification catalyst 11 and discharged into the atmosphere.

  On the other hand, in the control unit 30, the required driving force of the vehicle 1 is obtained based on the vehicle speed and the accelerator opening, and the target engine output is obtained based on the required driving force. Based on the target engine output, the optimal fuel consumption line used for controlling the actual engine output is stored in the control unit 30 in advance. Then, the target engine speed and the target engine torque are obtained so that the actual engine output is along the optimum fuel consumption line. Then, the gear ratio of the continuously variable transmission 12 is controlled in order to bring the actual engine speed close to the target engine speed. Further, the opening degree of the electronic throttle valve, the fuel injection amount, and the like are controlled in order to bring the actual engine torque close to the target engine torque.

  Of the above control, the control of the gear ratio of the continuously variable transmission 12 will be described more specifically. As described above, since the pressure p2 of the third pipe 25 is lower than the pressure p1 of the first pipe 23, a part of the exhaust gas flowing through the first pipe 23 passes through the orifice 27 due to the pressure difference. Then, it flows into the branch pipe 26. Further, the exhaust gas in the branch line 26 is returned to the third line 25 via the return line 28. When the exhaust gas passes through the orifice 27, the flow rate of the exhaust gas decreases, and the pressure (static pressure) of the exhaust gas in the branch pipe 26 is transmitted to the primary pressure chamber 18. At this time, by controlling the opening degree of the throttle valve 29, the pressure of the exhaust gas transmitted from the branch pipe 26 to the primary pressure chamber 18 can be controlled.

  Specifically, when the opening degree of the throttle valve 29 is relatively narrowed, the pressure of the exhaust gas transmitted from the branch pipe 26 to the primary pressure chamber 18 increases. When the pressure in the primary pressure chamber 18 rises, the groove width in the primary pulley 13 becomes narrow, and an upshift occurs in which the gear ratio of the continuously variable transmission 12 becomes relatively small. On the other hand, when the opening of the throttle valve 29 is relatively wide, the pressure in the primary pressure chamber 18 decreases. Then, the movable piece 20 moves toward the fixed piece 19 by the force of the compression spring of the secondary pressure chamber 21, the winding radius of the belt 15 in the secondary pulley 14 becomes relatively large, and the movable piece of the primary pulley 13 17 moves away from the fixed piece 16. In this way, a downshift occurs in which the gear ratio of the continuously variable transmission 12 becomes relatively large. It should be noted that the opening of the throttle valve 29 can be controlled to keep the pressure in the primary pressure chamber 18 constant, and the speed ratio of the continuously variable transmission 12 can be controlled to be constant. That is, the pressure transmission mechanism 22A has a function of controlling the pressure of the exhaust gas in the branch pipe line 26.

  Further, the control of the torque capacity of the continuously variable transmission 12 will be described. Similar to the control and action of the pressure transmission mechanism 22A, the torque is transmitted from the branch pipe 26 to the secondary pressure chamber 21 by the control and action of the pressure transmission mechanism 22B. The pressure of exhaust gas to be discharged can be controlled. Specifically, when the opening of the throttle valve 29 of the pressure transmission mechanism 22B is relatively narrowed, the pressure in the secondary pressure chamber 21 increases. For this reason, the clamping pressure applied to the belt 15 from the secondary pulley 14 increases, and the torque capacity of the continuously variable transmission 12 increases. On the other hand, if the opening degree of the throttle valve 29 of the pressure transmission mechanism 22B is relatively wide, the pressure in the secondary pressure chamber 21 is reduced, and the torque capacity of the continuously variable transmission 12 is reduced. It is also possible to control the opening of the throttle valve 29 of the pressure transmission mechanism 22B to keep the pressure of the secondary pressure chamber 21 constant and to control the torque capacity of the continuously variable transmission 12 to be constant.

  As described above, in this specific example, the energy of exhaust gas generated by the combustion of fuel, specifically, the pressure can be transmitted to the primary pressure chamber 18 and the secondary pressure chamber 21. For this reason, in order to generate the pressure supplied to the primary pressure chamber 18 and the secondary pressure chamber 21, it is not necessary to provide a hydraulic source such as a hydraulic pump having a large leakage loss. In addition, since the power of the engine 2 can be prevented from being consumed for driving the hydraulic pump, fuel efficiency is improved. Further, since the pressure transmission mechanisms 22A and 22B are not provided with a bearing that supports the rotating portion like a hydraulic pump, power loss of the engine 2 can be suppressed. Further, as in the case of using a hydraulic pump, it is not necessary to provide a valve body that forms an oil passage leading to the primary pressure chamber 18 and the secondary pressure chamber 21, which can contribute to downsizing of the continuously variable transmission 12.

  Furthermore, the pressure transmission mechanism 22 </ b> A changes the flow velocity of the exhaust gas by changing the cross-sectional areas of the first pipe line 23 and the third pipe line 25, and pressure is applied to the first pipe line 23 and the third pipe line 25. It makes a difference. Therefore, it is not necessary to provide a special mechanism such as a pressure reducing valve or a new pipe in the path through which the exhaust gas passes, and the first pipe line 23 and the A pressure difference can be generated between the third pipe line 25 and the third pipe line 25. Further, the first pipe line 23 is disposed upstream of the third pipe line 25 in the exhaust gas flow direction, and the cross-sectional area A1 of the first pipe line 23 is wider than the cross-sectional area of the third pipe line 25. . Here, if the pipes constituting the pipes have the same thickness, the surface area of the first pipe line 23 is larger than the surface area of the third pipe line 25, and the heat radiation area of the exhaust gas is relatively wide. . Accordingly, cooling of the exhaust pipe can be promoted, thermal fatigue of the exhaust pipe can be suppressed, and durability can be improved.

  In the specific example of FIG. 1, the pressure transmission mechanism 22A controls the pressure in the primary pressure chamber 18 while the pressure transmission mechanism 22B controls the pressure in the secondary pressure chamber 21. The pressure in the chamber 21 can be controlled by a pressurizing mechanism different from the pressure transmission mechanism 22B. For example, a pressurizing mechanism in which a spring that applies a preload to the movable piece 20 and a torque cam that can change the force applied to the movable piece 20 can be used in the secondary pressure chamber 21.

  Next, another configuration example of the pressure transmission mechanism for controlling the pressure in the primary pressure chamber 18 will be described with reference to FIG. The pressure transmission mechanism 22C shown in FIG. 2 is basically the same as the configuration of the pressure transmission mechanism 22A shown in FIG. 1, and the same components as those in FIG. is there. The pressure transmission mechanism 22C shown in FIG. 2 is different from the pressure transmission mechanism 22A shown in FIG. 1 in that a fourth pipe 31 connecting the third pipe 25 and the exhaust purification catalyst 11 is formed. Is different. The fourth pipe 31 is also a path through which the exhaust gas discharged from the engine 2 passes, and the cross-sectional area A3 of the fourth pipe 31 is configured wider than the cross-sectional area A2. The fourth conduit 31 is formed in the aforementioned metal tube.

  When exhaust gas flows from the exhaust pipe 9 into the pressure transmission mechanism 22C shown in FIG. 2, the exhaust gas reaches the exhaust purification catalyst 11 via the first pipe line 23 and the third pipe line 25, and FIG. The pressure in the primary pressure chamber 18 can be controlled by the same principle as the pressure transmission mechanism 22A shown. Further, in the pressure transmission mechanism 22C shown in FIG. 2, the same effects as in the case of FIG. 1 can be obtained with respect to the same components as the pressure transmission mechanism 22A shown in FIG.

  Next, a description will be given of a specific action and effect generated in the pressure transmission mechanism 22C shown in FIG. 2 because the cross-sectional area A3 of the fourth pipe 31 is larger than the cross-sectional area A2 of the third pipe 25. As the exhaust gas is discharged from the third pipeline 25 to the fourth pipeline 31, the flow resistance of the exhaust gas decreases. For this reason, it is possible to suppress an increase in the back pressure (engine back pressure) when exhaust gas is discharged from the combustion chamber of the engine 2 to the exhaust pipe 9, and it is possible to suppress a decrease in the combustion efficiency of the engine 2.

  When the pressure transmission mechanism 22C shown in FIG. 2 is provided to control the pressure in the primary pressure chamber 18, the pressure in the secondary pressure chamber 21 can be controlled by the pressurization mechanism described above. On the other hand, one more pressure transmission mechanism 22C shown in FIG. 2 may be provided, and the pressure in the secondary pressure chamber 21 may be controlled by this pressure transmission mechanism 22C. Further, in the above specific example, the power of the engine 2 is configured to be transmitted to the continuously variable transmission 12, but a power source having a power generation principle different from that of the engine 2 is provided. The vehicle may be configured such that the power from the power source is input to the continuously variable transmission. In such a vehicle, the engine 2 and the continuously variable transmission are not connected to transmit power. In addition, power sources having different power generation principles from the internal combustion engine include electric motors, flywheels, hydraulic motors, and the like.

  Here, the correspondence relationship between the specific examples shown in FIGS. 1 and 2 and the configuration of the present invention will be described. The continuously variable transmission 12 corresponds to the power transmission device of the present invention, and the movable pieces 17, 20. Corresponds to the movable member of the present invention, the primary pressure chamber 18 and the secondary pressure chamber 21 correspond to the pressure chamber of the present invention, the engine 2 corresponds to the internal combustion engine of the present invention, and the pressure transmission mechanisms 22A and 22B. 22C corresponds to the pressure transmission mechanism of the present invention, the first conduit 23 corresponds to the upstream conduit of the present invention, the third conduit 25 corresponds to the downstream conduit of the present invention, and the branch pipe The passage 26 and the return conduit 28 correspond to the bypass conduit of the present invention, and the fourth conduit 31 corresponds to the connecting conduit of the present invention.

  In addition, although the internal diameter in the plane cross section along the flow direction of exhaust gas is each comprised constant in the 1st pipe line 23 and the 3rd pipe line 25 shown by FIG. 1 and FIG. 2, the flow direction of exhaust gas In the planar cross section along the line, a taper may be applied so that the inner diameter decreases steplessly from the upstream flow path to the downstream flow path. That is, if the cross-sectional area of the downstream flow path is narrower than that of the upstream flow path in a plane perpendicular to the flow direction of the exhaust gas, the flow rate of the exhaust gas in the downstream flow path is higher than the flow rate of the exhaust gas in the upstream flow path. The flow rate becomes faster. In addition, the cross-sectional shapes of the upstream flow channel and the downstream flow channel may be elliptical in a plane perpendicular to the flow direction of the exhaust gas.

  Furthermore, the pressure transmission mechanism described in the above specific example may be used in a control device that controls a gear ratio and torque capacity of a continuously variable transmission other than a belt-type continuously variable transmission, for example, a toroidal continuously variable transmission. it can. The toroidal-type continuously variable transmission includes an input disk and an output disk, a power roller interposed between the input disk and the output disk, a trunnion for controlling a gear ratio by controlling a tilt angle of the power roller, an input And a pressurizing device that applies a clamping pressure to the disk and the output disk to control the torque capacity. A pressure chamber that reciprocates the trunnion linearly is provided, and the pressure chamber may be connected to the branch pipe 26 of the pressure transmission mechanism 22A. Moreover, what is necessary is just to connect the branch pipe line 26 of the pressure control apparatus 22B to the pressure chamber of a pressurization apparatus.

  Furthermore, the pressure transmission mechanism described in each specific example can also be used in a power transmission device other than a continuously variable transmission, for example, a control device that controls a forward / reverse switching device. The forward / reverse switching device is used in a vehicle having a continuously variable transmission, and the continuously variable transmission and the forward / reverse switching device are arranged in series on a path from a power source to a drive wheel. The forward / reverse switching device includes, for example, a planetary gear mechanism, a clutch that connects the rotating elements of the planetary gear mechanism, and a brake that controls the fixing or rotation of the rotating element. A switching device can be used. This planetary gear mechanism type forward / reverse switching device includes a clutch pressure chamber that controls engagement and disengagement of a clutch, and a brake pressure chamber that controls engagement and disengagement of a brake. This planetary gear mechanism type forward / reverse switching device is configured to be able to switch the rotation direction of the output member relative to the input member in the forward and reverse directions by controlling the engagement and release of the clutch and brake. The rotation direction of the output member relative to the input member of the forward / reverse switching device corresponds to the power transmission state of the power transmission device of the present invention. The pressure transmission mechanism described in each specific example is connected to at least one of the pressure chamber for the clutch and the pressure chamber for the brake, and the pressure in the pressure chamber for the clutch or the pressure chamber for the brake is controlled. can do.

  Furthermore, the pressure transmission mechanism and the pressure conversion mechanism described in each specific example can also be used in a power transmission device other than a continuously variable transmission, for example, a control device that controls a stepped transmission. The stepped transmission is provided, for example, on a path from the power source of the vehicle to the drive wheels, and the stepped transmission includes a planetary gear mechanism type stepped transmission. This planetary gear mechanism type stepped transmission has a planetary gear mechanism, a clutch for connecting or releasing the rotating elements of the planetary gear mechanism, and a brake for fixing or releasing the rotating element of the planetary gear mechanism. . The gear ratio of the planetary gear mechanism stepped transmission is changed stepwise (discontinuously) by controlling engagement and release of the clutch and brake. The planetary gear mechanism type stepped transmission includes a clutch pressure chamber that controls engagement and release of the clutch, and a brake pressure chamber that controls engagement and release of the brake. The pressure transmission mechanism described in the specific example is connected to at least one pressure chamber of the clutch pressure chamber or the brake pressure chamber to control the pressure of the clutch pressure chamber or the brake pressure chamber. be able to. In the above specific example, the present invention is applied to a vehicle. However, the present invention can also be used for a machine tool, a construction machine, or the like.

  DESCRIPTION OF SYMBOLS 2 ... Engine, 12 ... Continuously variable transmission, 17, 20 ... Movable piece, 18 ... Primary pressure chamber, 21 ... Secondary pressure chamber, 22A, 22B, 22C ... Pressure transmission mechanism, 23 ... First pipe, 25 ... First 3 pipelines, 26 ... branch pipeline, 28 ... bypass pipeline, 31 ... 4th pipeline.

Claims (3)

A power transmission device to which power is input; a movable member movably provided to control a power transmission state of the power transmission device; and a pressure chamber for generating a force to which the pressure is transmitted to the movable member In the control device of the power transmission device comprising:
An internal combustion engine that converts the thermal energy generated when the fuel is burned into kinetic energy and outputs it, and the exhaust gas generated when the fuel is burned in this internal combustion engine passes, and the pressure of the exhaust gas passes into the pressure chamber A pressure transmission mechanism for transmitting,
The pressure transmission mechanism includes an upstream pipe disposed relatively upstream in the flow direction of the exhaust gas, a downstream line disposed in the downstream of the upstream pipe in the flow direction of the exhaust gas, and the flow rate of the exhaust gas is an upstream pipe. And a bypass pipe connecting the upstream pipe and the downstream pipe, and the difference between the flow rate of the exhaust gas in the upstream pipe and the flow speed of the exhaust gas in the downstream pipe A process in which the exhaust gas in the upstream pipeline joins the downstream pipeline via the bypass pipeline due to a pressure difference between the pressure of the exhaust gas in the upstream pipeline and the exhaust gas in the downstream pipeline. Thus, the control device for the power transmission device is configured such that the pressure of the exhaust gas in the bypass pipe is transmitted to the pressure chamber.   The cross-sectional area in a plane perpendicular to the flow direction of the exhaust gas is configured such that the downstream pipe is narrower than the upstream pipe, so that the flow rate of the exhaust gas is faster in the downstream pipe than in the upstream pipe. The control device for a power transmission device according to claim 1, wherein:   A connecting pipe that is disposed downstream of the downstream pipe in the flow direction of the exhaust gas and that has a cross-sectional area in a plane perpendicular to the flow direction of the exhaust gas that is wider than the downstream pipe is provided. The control device for a power transmission device according to claim 2.

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