JP5115514B2 - Power transmission device - Google Patents

Description

  The present invention is a power transmission device that transmits power generated by an engine to drive wheels, and is driven by relative rotation between a cam and a cylinder disposed in a power transmission path from the engine to the drive wheels. This relates to an oil pump.

  For example, Patent Literature 1 discloses a power transmission device in which an oil pump is disposed in the middle of a vehicle power transmission path. The oil pump of Patent Document 1 is composed of a cam, a cylinder, and a piston, and the power transmission device of Patent Document 1 is retracted from the cam side with respect to the cylinder when power is not transmitted. The tip of the piston does not contact the cam surface, and the connection between the cylinder and the cam is released. In other words, when the piston is retracted from the cam side with respect to the cylinder and the tip of the piston does not contact the cam surface, the power generated by the engine is not transmitted to the drive wheels.

JP 2006-112659 A

  However, when the engine speed increases, the centrifugal force acting on the piston increases through the crankshaft and the cylinder. That is, when the engine speed increases, the piston may move radially outward with respect to the cylinder, that is, toward the cam surface due to centrifugal force. For this reason, when the rotational speed of the engine increases when power is not transmitted, the piston moves toward the cam surface with respect to the cylinder by centrifugal force, so that it abuts on the cam surface, for example, noise or vibration is generated. There is a risk that. That is, the power transmission device of Patent Document 1 has room for improvement in operation when power is not transmitted.

  The present invention has been made in view of the above, and an object of the present invention is to obtain a power transmission device capable of suppressing the generation of abnormal noise and vibration when power is not transmitted.

  In order to solve the above-described problems and achieve the object, a power transmission device according to the present invention is disposed in a power transmission path that transmits power generated by an engine to drive wheels, and pressurizes oil when power is transmitted. In the power transmission device, a cylinder to which power is transmitted from the engine, a cam coupled to the drive wheel, and a radially inner side from an outer peripheral surface of the cylinder facing a cam surface formed on an inner peripheral surface of the cam The cylinder chamber formed toward the cylinder and the cylinder chamber are sealed, and the cam is rotated relative to the cylinder from a contact position where the cylinder chamber can be brought into contact with the cam surface in the radial direction in the radial direction. A piston movable to a non-contact position that does not contact the surface; a suction control valve provided on the side of supplying the oil to the cylinder chamber; and the cylinder Between the suction control valve and the suction control valve, and opens with respect to the oil flow from the suction control valve toward the cylinder chamber, and with respect to the oil flow from the cylinder chamber toward the suction control valve. A suction-side check valve that closes and is provided on the side that discharges the oil to the cylinder chamber, and opens and discharges the oil flow from the cylinder chamber toward the discharge side. A discharge-side check valve that closes against the oil flow from the side toward the cylinder chamber, and a control device that controls opening and closing of the suction control valve, and the control device is transmitted to the cylinder. When the power is transmitted to the cam, the oil is supplied to the cylinder chamber by opening the suction control valve, the piston is moved to the contact position, and the cylinder is moved to the cylinder. When the transmitted power is not transmitted to the cam, when the power is not transmitted, the oil is not supplied into the cylinder chamber by closing the suction control valve, and the piston is moved to the non-contact position, and the engine The maximum rotational speed that is the upper limit of the rotational speed is set to an allowable rotational speed that can restrict the movement of the piston.

  The power transmission device according to the present invention is arranged in a power transmission path for transmitting the power generated by the engine to the drive wheels, and in the power transmission device that pressurizes oil during power transmission, the power is transmitted from the engine. A cylinder connected to the drive wheel, a cylinder chamber formed radially inward from an outer peripheral surface of the cylinder facing a cam surface formed on an inner peripheral surface of the cam, and the cylinder A piston that seals the chamber and is movable in a radial direction in the cylinder chamber from a contact position that can contact the cam surface to a non-contact position that does not contact the cam surface even if the cam rotates relative to the cylinder. A suction control valve provided on a side of supplying the oil to the cylinder chamber, and provided between the cylinder chamber and the suction control valve. A suction-side check valve which opens with respect to the oil flow from the suction control valve toward the cylinder chamber and closes with respect to the oil flow from the cylinder chamber toward the suction control valve; and the cylinder chamber The oil is provided on the oil discharge side, and is opened with respect to the oil flow from the cylinder chamber toward the discharge side, and the oil flow toward the cylinder chamber from the discharge side. A discharge-side check valve that is closed and a control device that controls the opening and closing of the suction control valve, and the control device is configured such that when the vehicle on which the engine is mounted is decelerated, the accelerator pedal of the vehicle is The intake control is performed when the engine is not depressed and the engine speed is less than an allowable speed capable of restricting the movement of the piston located at the non-contact position. Wherein without supplying the oil to the cylinder chamber, moves the piston to the non-contact position, it is characterized in that by closing the.

  In the present invention, there is an effect that generation of abnormal noise and vibration can be suppressed when power is not transmitted.

  Hereinafter, embodiments of a power transmission device according to the present invention will be described in detail with reference to the drawings. In addition, this invention is not limited by each following embodiment.

[Embodiment 1]
Hereinafter, the power transmission device according to the first embodiment will be described. FIG. 1 is a cross-sectional view illustrating a main part of the power transmission device according to the first embodiment. FIG. 2 is a schematic diagram showing an outline of the power transmission device. The power transmission device 1 is disposed in a power transmission path 22 that transmits power generated by the engine 20 to the drive wheels 21 and pressurizes oil during power transmission described later. The power transmission device 1 includes a cylinder 10, a cam 11, a cylinder chamber 12, a piston 13, a suction control valve 14, a suction side check valve 15, a discharge side check valve 16, and a flow rate control valve 17. ECU18. In the power transmission device 1, an oil pump 1 a is composed of a cylinder 10, a cam 11, a cylinder chamber 12, a piston 13, a suction side check valve 15, and a discharge side check valve 16. The pump 1a is a radial piston pump.

  The cylinder 10 is connected to the engine 20, and power is transmitted from the engine 20.

  The cam 11 is connected to the drive wheel 21, and transmits the power from the engine 20 received by the cylinder 10 to the drive wheel 21. The cam 11 has a cylindrical portion 111 extending to the cylinder 10 side in the rotation axis direction. A cam surface 111 a is formed on the inner peripheral surface of the cylindrical portion 111 orthogonal to the rotation axis of the cam 11. The cam surface 111a has a shape that repeats undulations continuously and periodically on the basis of a certain distance from the rotation axis of the cam 11 along the direction around the rotation axis of the cam 11, that is, in the circumferential direction. When viewed in the axial direction, it is wavy and annular.

  The cylinder chamber 12 is for reciprocating the piston 13 with respect to the cylinder 10 in the radial direction. The cylinder chamber 12 is formed radially inward from the outer peripheral surface 101 of the cylinder 10 facing the cam surface 111a.

  The piston 13 connects the cylinder 10 and the cam 11. The piston 13 is inserted into the cylinder chamber 12 from the outside in the radial direction of the cylinder chamber 12. The piston 13 is provided with a piston ring (not shown) at a circumferential portion in a direction orthogonal to the axial direction, and a gap between the circumferential surface and the cylinder chamber 12 is filled. That is, the piston 13 seals the cylinder chamber 12.

  The piston 13 is reciprocally movable in the radial direction inside the cylinder chamber 12. The piston 13 is disposed radially outward, that is, with respect to the cylinder 10 by a coil spring 132 disposed between a recess 131 formed at the radially inner end and a radially inner bottom 121 of the cylinder chamber 12. And biased toward the cam surface 111a. Still further, when the engine 20 is driven, the piston 10 is subjected to centrifugal force because the cylinder 10 rotates. That is, the piston 13 has a distal end that is urged by a biasing force by the coil spring 132 and a centrifugal force that is actuated by the rotation of the cylinder 10 as the engine 20 is driven in a state in which the suction control valve 14 described later is opened. The part 133 contacts the cam surface 111a and follows. Therefore, the piston 13 reciprocates in the radial direction when the cylinder 10 and the cam 11 rotate relative to each other with the intake control valve 14 opened. Further, when the suction control valve 14 is closed when the cylinder 10 and the cam 11 are rotating relative to each other, the piston 13 has an inner top portion that protrudes radially inward on the cam surface 111a. When passing, the distal end 133 moves radially inward from the inner top of the cam surface 111a due to inertial force when moving radially inward. That is, when the suction control valve 14 is closed when the cylinder 10 and the cam 11 are rotating relative to each other, the piston 13 will eventually eventually rotate relative to the cylinder 10. It will be located in the non-contact position which does not contact the cam surface 111a. As described above, the piston 13 is movable in the radial direction in the cylinder chamber 12 from a contact position where the piston 13 can contact the cam surface 111a to a non-contact position.

  Further, when the piston 13 tries to move outward in the radial direction by the urging force of the coil spring 132 and the centrifugal force that is acted by the rotation of the cylinder 10 as the engine 20 is driven, the suction oil described later is used. A negative pressure with respect to the oil pressure in the passage 1 b is generated in the cylinder chamber 12. The piston 13 sucks oil from the oil pan 23 into the cylinder chamber 12 by this negative pressure when the suction control valve 14 is opened. Hereinafter, the negative pressure generated in the cylinder chamber 12 when the piston 13 tries to move outward in the radial direction is simply referred to as negative pressure.

  The suction control valve 14 is for controlling whether or not oil is supplied to the cylinder chamber 12. The suction control valve 14 is provided on the side that supplies oil to the cylinder chamber 12. In the embodiment, the suction control valve 14 is provided in the suction oil passage 1b that connects the bottom 121 of the cylinder chamber 12 and the oil pan 23, and is opened by an instruction from the ECU 18 described later. The cylinder chamber 12 and the oil pan 23 are communicated. The suction control valve 14 is, for example, an electromagnetic valve, and the opening degree is adjusted based on an instruction from the ECU 18.

  For example, the suction side check valve 15 is provided between the cylinder chamber 12 and the suction control valve 14 in the suction oil passage 1b, and is supplied from the oil pan 23 into the cylinder chamber 12 through the suction oil passage 1b. This prevents the oil from flowing back into the intake oil passage 1b. The suction side check valve 15 opens with respect to the oil flow from the suction control valve 14 toward the cylinder chamber 12 and closes with respect to the oil flow toward the suction control valve 14 from the cylinder chamber 12.

  The discharge side check valve 16 prevents the oil discharged from the cylinder chamber 12 from flowing back into the cylinder chamber 12. In the embodiment, the discharge side check valve 16 is provided in the discharge oil passage 1 c that connects the bottom 121 of the cylinder chamber 12 and the hydraulic control unit 24. That is, the discharge-side check valve 16 is provided in the discharge oil passage 1 c that is the side that discharges oil to the cylinder chamber 12. The discharge-side check valve 16 opens with respect to the flow of oil from the cylinder chamber 12 toward the discharge oil passage 1c, and closes with respect to the flow of oil from the discharge oil passage 1c toward the cylinder chamber 12. The hydraulic control unit 24 regulates the oil supplied to the supply destination 25. The supply destination 25 is a target for supplying oil discharged from the oil pump 1a by the hydraulic control unit 24. For example, the hydraulic servo mechanism of the belt-type continuously variable transmission, the gear of the vehicle on which the engine 20 is mounted. And clutches.

  That is, in the state where the intake control valve 14 is opened, the oil pump 1a closes the discharge-side check valve 16 and closes the inside of the cylinder chamber 12 when the piston 13 moves radially outward. When the oil is sucked into the cylinder chamber 12 from the oil pan 23 due to the negative pressure and the piston 13 moves inward in the radial direction, the oil in the cylinder chamber 12 is pressurized by the piston 13, and the suction side check valve 15 Is closed and oil is discharged from the cylinder chamber 12 into the discharge oil passage 1c. That is, the oil pump 1a functions as an oil pump when the piston 13 reciprocates in the radial direction by the relative rotation of the cylinder 10 and the cam 11 with the suction control valve 14 opened. Become.

  The flow rate control valve 17 adjusts the flow rate of oil supplied from the oil pump 1a to the hydraulic pressure control unit 24. The flow control valve 17 is provided in the circulating oil passage 1d. The circulating oil passage 1d includes a portion between the suction control valve 14 and the suction-side check valve 15 in the suction oil passage 1b, and a portion closer to the hydraulic control unit 24 than the discharge-side check valve 16 in the discharge oil passage 1c. Is an oil passage connecting the two. The circulating oil passage 1d includes a cylinder chamber 12 side from a connection portion with the circulation oil passage 1d in the suction oil passage 1b, a cylinder chamber 12 side from a connection portion with the circulation oil passage 1d in the discharge oil passage 1c, and a cylinder chamber. 12 constitutes a closed-loop oil passage. The flow rate control valve 17 increases the flow rate of the oil flowing through the circulating oil passage 1d with respect to the flow rate of the oil discharged from the oil pump 1a as the opening degree increases, and thereby the hydraulic control from the oil pump 1a. The flow rate of oil supplied to the unit 24 is decreased. The flow control valve 17 is, for example, an electromagnetic valve, and the opening degree is adjusted based on an instruction from the ECU 18.

  The flow rate control valve 17 controls the differential rotation speed, which is a relative rotation amount per unit time between the cylinder 10 and the cam 11. The flow control valve 17 increases the differential rotation speed between the cylinder 10 and the cam 11 as the opening degree is increased. That is, the flow rate control valve 17 increases the flow rate of the oil returned to the oil pump 1a via the circulating oil passage 1d with respect to the flow rate of the oil discharged from the oil pump 1a. The differential rotation speed is increased.

  The ECU 18 is a control device. The ECU 18 controls the opening and closing of the suction control valve 14, thereby controlling the supply of oil from the oil pan 23 into the cylinder chamber 12. The ECU 18 includes an engine ECU (not shown) and a transmission ECU (not shown).

  The engine ECU controls the operation of the engine 20. The engine ECU controls the torque generated by the engine 20 when transmitting the power transmitted from the engine 20 to the cylinder 10 to the cam 11. On the other hand, the engine ECU controls the rotational speed of the engine 20 when power is not transmitted to the cam 11 so that power transmitted from the engine 20 to the cylinder 10 is not transmitted, for example, when idling. When the power is not transmitted, the engine ECU outputs an electrical instruction to the throttle 20a according to the amount of depression of the accelerator pedal by the driver, for example, and controls the opening of the throttle 20a. The number of rotations of 20 is controlled. That is, for example, the ECU 18 controls the rotation speed of the engine 20 by controlling the opening of the throttle 20a in accordance with the amount of depression of the accelerator pedal by the driver, and thereby the hydraulic pressure in the cylinder chamber 12 is controlled. To control. More specifically, as the number of revolutions of the engine 20 is increased by the ECU 18, the number of revolutions of the cylinder 10 per unit time increases, thereby increasing the number of reciprocating movements of the piston 13 per unit time. The hydraulic pressure in the cylinder chamber 12 will increase.

  The transmission ECU controls, for example, the opening degree of the suction control valve 14, the opening degree of the flow rate control valve 17, and the oil pressure regulation by the hydraulic control unit 24 according to the driving state of the vehicle. When transmitting power, the transmission ECU outputs an electrical instruction to the intake control valve 14 and opens the intake control valve 14. Further, the transmission ECU outputs an electrical instruction to the suction control valve 14 when power is not transmitted, and closes the suction control valve 14. Further, the transmission ECU outputs an electrical instruction to the flow control valve 17 in accordance with the driving state of the vehicle and controls the opening degree of the flow control valve 17, so that the difference between the cylinder 10 and the cam 11 is achieved. Control the number of revolutions. That is, the ECU 18 controls the transmission rate of the power generated by the engine 20 between the cylinder 10 and the cam 11 by controlling the opening degree of the flow control valve 17 according to the driving state of the vehicle. More specifically, as the opening degree of the flow control valve 17 is increased by the ECU 18, the differential rotation speed between the cylinder 10 and the cam 11 increases, and the power generated by the engine 20 between the cylinder 10 and the cam 11. The transmission rate of decreases. Further, the transmission ECU outputs an electrical instruction to the hydraulic control unit 24 according to the driving state of the vehicle, and adjusts the oil supplied to the supply destination 25 by the hydraulic control unit 24.

  Next, the operation of the power transmission device 1 according to the first embodiment will be described.

In the state where the engine 20 is driven, the ECU 18 outputs an electrical instruction to the intake control valve 14 and opens the intake control valve 14 to transmit oil into the cylinder chamber 12 during power transmission. Supply. Thus, ECU 18, by opening the suction control valve 14, to supply oil to the cylinder chamber 12, the oil pressure in the cylinder chamber 12 corresponding to the rotational speed N _e of the engine 20 at the time of power transmission, the piston The cam surface 111a is moved in the circumferential direction while pressing 13 against the cam surface 111a according to the power generated by the engine 20. At this time, the piston 13 alternately repeats the movement outward in the radial direction with respect to the cylinder 10 and the movement inward in the radial direction with respect to the cylinder 10 to supply oil from the oil pan 23 into the cylinder chamber 12. And the discharge of oil from the cylinder chamber 12 to the discharge oil passage 1c are alternately repeated. At this time, for example, if the flow control valve 17 is closed by the ECU 18, the oil discharged from the cylinder chamber 12 is supplied to the hydraulic control unit 24 via the discharge oil passage 1c. Based on an instruction from the ECU 18, the hydraulic control unit 24 adjusts the oil supplied to the supply destination 25 and supplies the adjusted oil to the supply destination 25.

  Further, at the time of power transmission, the ECU 18 outputs an electrical instruction to the flow rate control valve 17 according to the operating state, and opens the flow rate control valve 17 from the closed state. The differential rotation speed with respect to the cam 11 is increased. At the time of power transmission, the ECU 18 opens the flow control valve 17 from the closed state, thereby increasing the differential rotational speed between the cylinder 10 and the cam 11 as the opening degree of the flow control valve 17 increases. As a result, the transmission rate of the power generated by the engine 20 between the cylinder 10 and the cam 11 is reduced. That is, at the time of power transmission, the power generated by the engine 20 is transmitted from the cylinder 10 to the cam 11 via the piston 13 and finally to the drive wheel 21.

  On the other hand, when the engine 20 is driven, when power is not transmitted, the ECU 18 outputs an electrical instruction to the intake control valve 14 and closes the intake control valve 14, so that the inside of the cylinder chamber 12 is closed. In addition, the piston 13 is moved to the non-contact position by moving the piston 13 in the circumferential direction on the cam surface 111a by the relative rotation of the cam 11 and the cylinder 10 without supplying oil. More specifically, when the piston 13 moves inward in the radial direction with respect to the cylinder 10, the oil in the cylinder chamber 12 is pressurized by the piston 13, so that the volume of the cylinder chamber 12 is reduced to the discharge oil passage 1 c. Discharged. Finally, the piston 13 moves to the non-contact position by an inertial force when moving inward in the radial direction. When the piston 13 moves to the non-contact position, it tends to move toward the cam surface 111a by the urging force of the coil spring 132. However, since the suction control valve 14 has already been closed by the ECU 18, the cylinder chamber 12 has a negative pressure, but cannot suck oil from the suction oil passage 1b. Therefore, since the intake control valve 14 is closed, the volume of the cylinder chamber 12 does not increase. That is, since the intake control valve 14 is closed, the piston 13 can move toward the cam surface 111a even when the biasing force of the coil spring 132 and the centrifugal force due to the rotation of the cylinder 10 are applied. It cannot be done and will be kept in a non-contact position. Accordingly, since the piston 13 is held at the non-contact position, the connection between the cylinder 10 and the cam 11 by the piston 13 is released. That is, when power is not transmitted, the power generated by the engine 20 is not transmitted from the cylinder 10 to the cam 11 via the piston 13, and is not transmitted to the drive wheels 21.

  The power transmission device 1 according to the first embodiment further performs processing as described below when power is not transmitted. Hereinafter, this process will be described.

FIG. 3 is a diagram showing a flowchart of the operation of the power transmission device 1 according to the first embodiment when power is not transmitted. When the vehicle on which the engine 20 is mounted is stopped while the engine 20 is being driven and the driver selects the P position or the N position, the ECU 18 sets the maximum rotation speed N _emax to the allowable rotation speed. N ₀ is set (step S100). Here, the maximum rotational speed N _emax is an upper limit of the rotational speed of the engine 20. Further, the allowable rotational speed N ₀ is a rotational speed that can regulate the movement of the piston 13 located at the non-contact position along the radial direction. That is, the allowable rotational speed N ₀ is a rotational speed at which the piston 13 can be kept in the non-contact position, and the ECU 18 sets the maximum rotational speed N _emax that is the upper limit of the rotational speed of the engine 20 when power is not transmitted. This allowable rotational speed N ₀ is set.

Here, the allowable rotational speed N ₀ is obtained as follows. In FIG. 1, the force F <b> 1 acting radially outward with respect to the piston 13 is a resultant force of the urging force of the coil spring 132 and the centrifugal force acting on the piston 13 when the cylinder 10 is rotated by the engine 20. is there. On the other hand, in FIG. 1, the force F2 acting radially inward with respect to the piston 13 is the cylinder chamber when the intake control valve 14 is closed and the piston 13 is located at the non-contact position. 12 is a negative pressure resistance based on the negative pressure in the circuit 12. The negative pressure, that is, the negative pressure in the cylinder chamber 12 when the suction control valve 14 is closed and the piston 13 is located at the non-contact position is set to, for example, −0.1 MPa. ing. Since the forces along the radial direction acting on the piston 13 when power is not transmitted are the force F1 and the force F2, the rotational speed of the cylinder 10 when power is not transmitted is F1 ≦ F2 (Expression 1)
Can always be established, the power transmission device 1 can keep the piston 13 in the non-contact position. That is, as long as it can always hold speed N _e of the engine 20 (Formula 1) at the time of non-power transmission, the power transmission apparatus 1 can keep the piston 13 in a non-contact position. That is, the rotational speed N _e of the engine 20 that always holds (Equation 1) when power is not transmitted is the rotational speed at which the piston 13 can be kept in the non-contact position, that is, the allowable rotational speed N _0. . In the first embodiment, to at the time of non-power transmission as the upper limit of the rotational speed N _e of the engine 20, such as always to establish (Equation 1) is allowable speed N _0.

Thus, since the ECU 18 sets the maximum rotational speed N _emax of the engine 20 to the allowable rotational speed N ₀ , even when the rotational speed N _e of the engine 20 reaches the upper limit when power is not transmitted, the piston 13 Will be held in a non-contact position.

Next, the ECU 18 determines whether or not the rotational speed N _e of the engine 20 is smaller than the maximum rotational speed N _emax (step S101). That is, the ECU 18 determines whether or not the rotational speed N _e of the engine 20 is smaller than the allowable rotational speed N ₀ .

Next, when the ECU 18 determines that the rotational speed N _e of the engine 20 is not smaller than the maximum rotational speed N _emax (No in step S101), the throttle opening degree θ that is the opening degree of the throttle 20a is set to “θ−Δθ”. Set (step S102). That is, when the ECU 18 determines that the rotational speed N _e of the engine 20 is equal to or greater than the allowable rotational speed N ₀ , the ECU 18 reduces the throttle opening θ by a slight amount Δθ from the current state, and the rotational speed N _{e of the} engine 20. To be smaller than the current situation. For example, ECU 18 (here, cooling device) air conditioning system in use by the driver and the switch to OFF, when the rotational speed N _e of the engine 20 increases, the rotational speed N _e of the engine 20 is allowable rotation When it is determined that a number N ₀ or more, and smaller by a small amount Δθ than the current throttle opening theta, smaller than the current rotational speed N _e of the engine 20.

Next, the ECU 18 determines again whether or not the rotational speed N _{e of the} engine 20 is smaller than the maximum rotational speed N _emax (step S101).

Next, when the ECU 18 determines that the rotational speed N _e of the engine 20 is smaller than the maximum rotational speed N _emax (Yes in step S101), it is determined whether or not the rotational speed N _e of the engine 20 is larger than the minimum rotational speed N _emin . Is determined (step S103). That, ECU 18 is speed N _e of the engine 20 to determine whether or not reduced to rotational speed occurs the engine stop.

Next, when the ECU 18 determines that the rotational speed N _e of the engine 20 is not greater than the minimum rotational speed N _emin (No in step S103), the throttle opening θ that is the opening of the throttle 20a is set to “θ + Δθ”. (Step S104). That, ECU 18, when the rotational speed N _e of the engine 20 is determined to be lowered to the rotational speed which occurs the engine stop, is increased by a small amount Δθ than the current throttle opening theta, engine the speed _{N e} of 20 larger than the current.

Next, the ECU 18 determines again whether or not the rotational speed N _{e of the} engine 20 is smaller than the maximum rotational speed N _emax (step S101).

Next, when the ECU 18 determines that the rotational speed N _e of the engine 20 is smaller than the maximum rotational speed N _emax (Yes in step S101), it is determined whether or not the rotational speed N _e of the engine 20 is larger than the minimum rotational speed N _emin . Is determined (step S103).

Then, ECU 18, when the rotational speed _{N e} of the engine 20 is determined to be larger than the minimum rotational speed _{N emin} (Yes at step S103), and terminates the control for adjusting the rotational speed _{N e} of the engine 20. However, ECU 18, after the completion of the control of adjusting the rotation speed N _e of the engine 20 is also a state in which the engine 20 is being driven, yet, the vehicle engine 20 is mounted is at a power non-transmission case, immediately resumes control of the rotational speed N _e of the engine 20.

As described above, in the power transmission device 1, since the maximum rotation speed N _emax of the engine 20 is set to the allowable rotation speed N ₀ by the ECU 18, even if the rotation speed N _e of the engine 20 increases and reaches the upper limit, The piston 13 does not move toward the cam surface 111a with respect to the cylinder 10 and is held at the non-contact position. Therefore, the power transmission device 1, when the power non-transmission, also reaches the speed N _e is increased the upper limit of the engine 20, the piston 13, the contact position from the non-contact position under the centrifugal force generated by the rotation of the cylinder 10 Never move on. That is, in the power transmission device 1, it is possible to suppress the generation of noise or vibration due to the tip 133 of the piston 13 coming into contact with, for example, the inner top of the cam surface 111 a when power is not transmitted.

[Embodiment 2]
Next, a power transmission device according to Embodiment 2 will be described. FIG. 4 is a block diagram for explaining a main part of the power transmission device according to the second embodiment. Power transmission device 1 according to the second embodiment, when the control of the rotational speed N _e of the engine 20 at the time of non-power transmission by ECU18 described in the first embodiment are performed, i.e., when current is non-power transmission When the shift position is the D position or the R position, and the driver steps on the accelerator pedal in this state, the cylinder 10 and the cam 11 are connected to generate the engine 20. Power is transmitted to the drive wheels 21. Here, the basic configuration of the power transmission device according to the second embodiment is the same as that of the power transmission device according to the first embodiment, and thus the description thereof is omitted.

The ECU 18 sets the throttle opening θ based on both the accelerator opening α and the throttle opening command value θ ₀ . Here, the accelerator opening α is a variable corresponding to the amount of depression of the accelerator pedal by the driver, and takes a positive or zero value. That is, the value of the accelerator opening α increases as the amount of depression of the accelerator pedal by the driver increases. The throttle opening command value θ ₀ is a reference value for the throttle opening θ, and is the value of the throttle opening θ when the accelerator opening α is zero. Further, the ECU 18 can appropriately set an amplification factor G that is a value of a change amount of the throttle opening θ with respect to a change amount of the accelerator opening α,
θ = θ ₀ + Gα (Expression 2)
Is required.

  In the state where the engine 20 is driven, the operation during power transmission of the power transmission device 1 of the second embodiment is the same as that of the first embodiment. The power transmission device 1 according to the second embodiment performs the same processing as the power transmission device 1 according to the first embodiment when power is not transmitted, and further performs processing as described below. . Hereinafter, this process will be described.

  FIG. 5 is a flowchart of the operation of the power transmission device 1 according to the second embodiment when power is not transmitted. In the power transmission device 1 according to the second embodiment, the ECU 18 determines whether or not the intake control valve 14 is closed (step S110). That is, the ECU 18 determines whether or not the current state is when power is not transmitted, depending on whether or not the suction control valve 14 is closed.

Next, when the ECU 18 determines that the intake control valve 14 is closed (Yes at Step S110), the ECU 18 determines whether the shift position is either the P position or the N position (Step S111). That is, in the power transmission device 1, when the current state is when power is not transmitted, the ECU 18 _sets the rotation speed N _e of the engine 20 to the minimum rotation speed N _emin and the maximum rotation speed N _emax set to the allowable rotation speed N _0. The ECU 18 determines whether or not the state at the time of non-transmission of power is continued in a state where the rotational speed is controlled to be between.

Next, when the ECU 18 determines that the shift position is the P position or the N position (Yes at Step S111), the ECU 18 sets the gain G to 0 (Step S112). That is, when the ECU 18 determines that the state at the time of non-transmission of power is continued, the throttle opening θ is set based on (Equation 2) by setting the amplification factor G to 0.
θ = θ ₀ (Formula 3)
Set to.

Then, when the amplification factor G is set to 0, the ECU 18 outputs an electrical instruction to the throttle 20a and sets the actual throttle opening θ of the throttle 20a to the throttle opening command value represented by (Equation 3). θ _{0 is} assumed. In other words, the ECU 18 sets the actual throttle opening θ of the throttle 20a to the minimum value even when the driver depresses the accelerator pedal when the shift position is the P position or the N position when power is not transmitted. Keep it. That is, when power is not transmitted and the shift position is the P position or the N position, the ECU 18 prohibits the opening of the throttle 20a even if the driver depresses the accelerator pedal. ECU18, when the actual throttle opening theta of the throttle 20a and the throttle opening command value theta _0, and terminates the control of the opening degree of the throttle 20a. However, the ECU 18 is in a state where the engine 20 is still driven even after the control of the opening degree of the throttle 20a is finished, and when the vehicle on which the engine 20 is mounted is not transmitting power, immediately. The control of the opening degree of the throttle 20a is resumed.

  Next, the ECU 18 determines whether or not the intake control valve 14 is closed (step S110).

  Next, when the ECU 18 determines that the intake control valve 14 is closed (Yes at Step S110), the ECU 18 determines whether the shift position is either the P position or the N position (Step S111).

  Next, when the ECU 18 determines that the shift position is not the P position or the N position (No at Step S111), the ECU 18 sets the gain G to a positive value G (Step S113). That is, if the ECU 18 determines that the shift position has been switched from the P position or the N position to the D position or the R position by the driver, that is, if the ECU 18 determines that there is a possibility of switching from the non-power transmission to the power transmission, the amplification is performed. When the rate G is set to a positive value G and the accelerator pedal is depressed by the driver, the throttle 20a can be opened.

  Next, when the amplification factor G is set to a positive value G, the ECU 18 determines whether or not the accelerator opening α is a positive value (step S114). That is, the ECU 18 determines whether or not the accelerator pedal is depressed by the driver.

  Next, when the ECU 18 determines that the accelerator opening α is 0 (No at Step S114), the ECU 18 returns to Step S111. That is, if ECU18 judges that the accelerator pedal is not depressed by the driver, it will return to Step S111.

  Next, the ECU 18 determines whether or not the shift position is either the P position or the N position (step S111).

  Next, when the ECU 18 determines that the shift position is not the P position or the N position (No at Step S111), the ECU 18 sets the gain G to a positive value G (Step S113). Here, since the gain G has already been set to a positive value G, the ECU 18 does not change the set value of the gain G.

  Next, when the amplification factor G is set to a positive value G, the ECU 18 determines whether or not the accelerator opening α is a positive value (step S114).

  Next, when the ECU 18 determines that the accelerator opening α is a positive value (Yes at Step S114), the ECU 18 opens the intake control valve 14 (Step S115). That is, when the ECU 18 determines that the accelerator pedal has been depressed by the driver, the ECU 18 determines that the vehicle on which the engine 20 is mounted has shifted from the state in which power is not transmitted to the state in which power is transmitted, and the intake control valve 14 On the other hand, an electrical instruction is output and the suction control valve 14 is opened.

  Here, when the intake control valve 14 is opened by the ECU 18, the vehicle on which the engine 20 is mounted shifts from the power non-transmission state to the power transmission state. The power from the engine 20 received by the cylinder 10 is transmitted to the drive wheels 21 through the piston 13 and the cam 11.

  That is, when the ECU 18 determines that the accelerator pedal has been depressed by the driver, the ECU 18 opens the intake control valve 14 to end the state when the power is not transmitted, and changes from the state when the power is not transmitted to the state when the power is transmitted. Switch. For example, on the road, the shift position is the D position, and the driver depresses the brake pedal while waiting for a signal, and then the driver releases the brake pedal and depresses the accelerator pedal, This corresponds to the case of starting a vehicle on which 20 is mounted.

At this time, the ECU 18 determines the throttle opening θ based on (Equation 2).
θ = θ ₀ + Gα (Expression 4)
Set to.

Then, the ECU 18 outputs an electrical instruction to the throttle 20a and sets the actual throttle opening θ of the throttle 20a to throttle opening θ = θ ₀ + Gα expressed by (Equation 4). When the actual throttle opening θ of the throttle 20a is set to throttle opening θ = θ ₀ + Gα, the ECU 18 ends the control of the opening of the throttle 20a.

  If the ECU 18 determines that the intake control valve 14 is not closed (No at Step S110), that is, if the ECU 18 determines that the intake control valve 14 is opened, the control of the opening degree of the throttle 20a is immediately terminated. To do. However, the ECU 18 is in a state where the engine 20 is still driven even after the control of the opening degree of the throttle 20a is finished, and when the vehicle on which the engine 20 is mounted is not transmitting power, immediately. The control of the opening degree of the throttle 20a is resumed.

As described above, in the power transmission device 1 of the second embodiment, when the control of the rotational speed N _e of the engine 20 at the time of non-power transmission by ECU18 described in the first embodiment is executed by the driver When the shift position is switched from the P position or the N position to the D position or the R position, and the driver steps on the accelerator pedal, the piston 10 connects the cylinder 10 and the cam 11 to generate the engine 20. The power to be transmitted can be transmitted to the drive wheel 21.

[Embodiment 3]
Next, a power transmission device according to Embodiment 3 will be described. 6, the power transmission device according to the third embodiment, when the vehicle in which the engine 20 is mounted is decelerated, a diagram showing a timing chart for controlling the rotational speed N _e of the engine 20. The power transmission device 1 according to the third embodiment, during deceleration of the vehicle engine 20 is mounted, not the accelerator pedal of the vehicle is depressed, yet, the rotational speed of the engine 20 N _e is permissible speed When the _value falls below N ₀ , the vehicle is shifted from the power transmission state to the power non-transmission state. Further, the power transmission apparatus 1 according to the third embodiment, during deceleration of the vehicle engine 20 is mounted, the suction control valve 14 before the rotational speed N _e of the engine 20 falls below the minimum rotational speed N _emin closed In this way, the power generated by the engine 20 is not transmitted to the drive wheels 21 by releasing the connection between the cylinder 10 and the engine 20. Here, the basic configuration of the power transmission device according to the third embodiment is the same as that of the power transmission device according to the first embodiment, and thus the description thereof is omitted.

The ECU18 in the third embodiment, during deceleration of the vehicle engine 20 is mounted, not the accelerator pedal is depressed for a vehicle engine 20 is mounted, yet, the allowable speed N _e of the engine 20 is If it is less than the rotational speed N _0, without supplying oil to the cylinder chamber 12 by closing the intake control valve 14, the circumferential direction of the piston 13 in the cam surface 111a by the relative rotation between the cam 11 and the cylinder 10 Is moved to the non-contact position.

  FIG. 7 is a diagram illustrating a flowchart of the operation of the power transmission device 1 according to the third embodiment when power is not transmitted. In the power transmission device 1 according to the third embodiment, when the engine is driven and the accelerator pedal is depressed by the driver and the vehicle on which the engine 20 is mounted travels, the ECU 18 is turned off. It is determined whether or not (step S120). That is, the ECU 18 determines whether or not the driver has stopped pressing the accelerator pedal and the vehicle on which the engine 20 is mounted has been decelerated.

Then, ECU 18 determines that not in the accelerator OFF (step S120: No), ends the control of the rotational speed _{N e} of the engine 20. However, ECU 18, if the vehicle in which the engine 20 is mounted is traveling immediately resume control of the rotational speed _{N e} of the engine 20, it is determined whether it is the accelerator OFF (step S120).

  Next, the ECU 18 determines whether or not the accelerator is turned off (step S120).

Then, ECU 18 determines that becomes the accelerator OFF (step S120: Yes), it is determined whether or not the rotational speed _{N e} of the engine 20 is smaller than the allowable rotation speed _{N 0} (step S121). That is, when the driver stops the depression of the accelerator pedal and the vehicle on which the engine 20 is mounted is decelerated, the ECU 18 temporarily turns off the piston 13 when the intake control valve 14 is closed. It is determined whether or not the contact position can be maintained.

Next, when the ECU 18 determines that the rotational speed N _e of the engine 20 is not smaller than the allowable rotational speed N ₀ (No in step S121), the ECU 18 starts fuel cut (step S122). That is, the ECU 18 keeps the piston 13 in the non-contact position even if the intake control valve 14 is closed when the driver stops the depression of the accelerator pedal and the vehicle on which the engine 20 is mounted is decelerated. when it is determined that it is impossible to keep, the initiate the fuel cut in the engine 20, reduce the speed N _e of the engine 20.

  Next, the ECU 18 determines whether or not the accelerator is ON (step S123). That is, the ECU 18 determines whether or not the driver has stepped on the accelerator pedal and the vehicle on which the engine 20 is mounted is no longer in a deceleration state. In other words, the ECU 18 determines whether or not the driver depresses the accelerator pedal and the vehicle on which the engine 20 is mounted is in a state where the speed is maintained or in an accelerated state.

Next, when the ECU 18 determines that the accelerator is ON (Yes at Step S123), the fuel cut ends (Step S125). That, ECU 18 is depressed the driver on the accelerator pedal, the vehicle engine 20 is mounted is determined to no longer the deceleration state, to terminate the fuel cut in the engine 20, increasing the speed N _e of the engine 20 . In other words, the ECU 18 restarts the engine 20 when the driver depresses the accelerator pedal and determines that the vehicle on which the engine 20 is mounted maintains the vehicle speed or the acceleration state. increasing the rotational speed _{N e.} Incidentally, ECU 18 has finished fuel cut, terminates the control of the rotational speed _{N e} of the engine 20. However, ECU 18, since the vehicle engine 20 is mounted is traveling immediately resumes control of the rotational speed _{N e} of the engine 20 of the engine 20.

Further, ECU 18 determines that not in the accelerator ON (step S123 negative), it is determined whether or not the rotational speed _{N e} of the engine 20 is smaller than the allowable rotation speed _{N 0} (step S121). That is, when the ECU 18 determines that the driver does not depress the accelerator pedal and the deceleration state of the vehicle on which the engine 20 is mounted is maintained, the piston 18 does not contact the piston 13 when the intake control valve 14 is closed. It is determined whether or not it is possible to remain in position.

Then, ECU 18 determines that the rotational speed _{N e} of the engine 20 is smaller than the allowable rotation speed _{N 0} (step S121: Yes), closes the suction control valve 14 (step S124). That is, when the driver stops the depression of the accelerator pedal and the vehicle on which the engine 20 is mounted is decelerated, the ECU 18 closes the piston 13 when the intake control valve 14 is closed. If it is determined that the intake control valve 14 can be retained, the suction control valve 14 is closed. At this time, the ECU 18 determines that the power is not being transmitted, and sets the maximum rotation speed N _emax to the allowable rotation speed N ₀ .

Next, the ECU 18 ends the fuel cut (step S125). That, ECU 18 causes the restarting the engine 20, so as not to reduce the speed _{N e} of the engine 20. Here, ECU 18, as speed _{N e} of the engine 20 is not reduced to the minimum rotational speed _{N emin,} controls the speed _{N e} of the engine 20. Incidentally, ECU 18 has finished fuel cut, terminates the control of the rotational speed _{N e} of the engine 20. However, ECU 18, since the vehicle engine 20 is mounted is traveling immediately resumes control of the rotational speed N _e of the engine 20.

As described above, when the rotational speed N _e of the engine 20 falls below the allowable rotational speed N ₀ during deceleration of the vehicle on which the engine 20 is mounted, the vehicle on which the engine 20 is mounted is controlled by the power transmission device 1. Transition from the state when power is transmitted to the state when power is not transmitted. That is, in the power transmission device 1 when power is not transmitted, it is possible to suppress the generation of noise or vibration due to the tip 133 of the piston 13 coming into contact with, for example, the inner top of the cam surface 111a.

Further, the power transmission device 1 of the third embodiment, since the speed N _e of the engine 20 at the time of transition from the state at the time of power transmission state when the power non-transmission is greater than the minimum rotational speed N _emin, engine 20 also the speed N _e not dropped until the rotational speed of the engine stop is generated, the vehicle engine 20 is mounted, it is possible to shift from the state at the time of power transmission state during non-power transmission.

Further, the power transmission device 1 of the third embodiment, and controls the speed N _e of the engine 20 during non-power transmission so as not to reduce to the minimum rotational speed N _emin, during power transmission from the state during non-power transmission When the state is shifted to this state, it is possible to suppress an increase in torque fluctuation generated between the cylinder 10 and the cam 11 due to the restart of the engine 20. In other words, the power transmission device 1 of the third embodiment, the rotational speed N _e of the engine 20 during non-power transmission, since previously maintained so as not to worsen until the rotational speed of the engine stop is generated, the power Even when the cylinder 10 and the cam 11 are connected by the piston 13 when the state is shifted from the non-transmission state to the power transmission state, it is possible to suppress an increase in vibration due to the connection.

  As described above, the power transmission device according to the present invention is useful as a power transmission device that is required to be quiet and vibration-proof when power is not transmitted. In particular, the power transmission device includes a radial pump in the middle of the power transmission path. It is useful as a power transmission device.

FIG. 1 is a cross-sectional view illustrating a main part of the power transmission device according to the first embodiment. FIG. 2 is a schematic diagram showing an outline of the power transmission device. FIG. 3 is a diagram illustrating a flowchart of the operation of the power transmission device when power is not transmitted. FIG. 4 is a block diagram for explaining a main part of the power transmission device according to the second embodiment. FIG. 5 is a diagram illustrating a flowchart of the operation of the power transmission device when power is not transmitted. FIG. 6 is a timing chart for controlling the engine speed when the vehicle on which the engine is mounted is decelerated by the power transmission device according to the third embodiment. FIG. 7 is a diagram illustrating a flowchart of the operation of the power transmission device when power is not transmitted.

DESCRIPTION OF SYMBOLS 1 Power transmission device 10 Cylinder 101 Cylinder outer peripheral surface 11 Cam 111a Cam surface 12 Cylinder chamber 13 Piston 14 Suction control valve 15 Suction side check valve 16 Ejection side check valve 18 ECU (control device)
20 Engine 21 Drive wheel 22 Power transmission path N _e Engine speed N ₀ Allowable speed N _emax Maximum speed N _emin Minimum speed

Claims (2)

In a power transmission device that is disposed in a power transmission path that transmits power generated by an engine to driving wheels, and pressurizes oil during power transmission,
A cylinder to which power is transmitted from the engine;
A cam coupled to the drive wheel;
A cylinder chamber formed radially inward from the outer peripheral surface of the cylinder facing the cam surface formed on the inner peripheral surface of the cam;
The cylinder chamber is hermetically sealed and movable in a radial direction in the cylinder chamber from a contact position that can contact the cam surface to a non-contact position that does not contact the cam surface even if the cam rotates relative to the cylinder. A piston,
A suction control valve provided on the side of supplying the oil to the cylinder chamber;
The oil flow that is provided between the cylinder chamber and the suction control valve, opens with respect to the oil flow from the suction control valve toward the cylinder chamber, and flows from the cylinder chamber toward the suction control valve. A suction-side check valve that closes against
The oil is provided on the side of the cylinder chamber that discharges the oil, and opens when the oil flows from the cylinder chamber toward the discharge side. A discharge check valve that closes against the flow;
A control device for controlling opening and closing of the suction control valve;
With
The controller is
When transmitting the power transmitted to the cylinder to the cam, the oil is supplied to the cylinder chamber by opening the suction control valve, and the piston is moved to the contact position.
When the power transmitted to the cylinder is not transmitted to the cam, when the power is not transmitted, the oil is not supplied into the cylinder chamber by closing the suction control valve, and the piston is moved to the non-contact position. The maximum rotational speed that is the upper limit of the rotational speed of the engine is set to an allowable rotational speed that can restrict the movement of the piston.
A power transmission device characterized by that. In a power transmission device that is disposed in a power transmission path that transmits power generated by an engine to driving wheels, and pressurizes oil during power transmission,
A cylinder to which power is transmitted from the engine;
A cam coupled to the drive wheel;
A cylinder chamber formed radially inward from the outer peripheral surface of the cylinder facing the cam surface formed on the inner peripheral surface of the cam;
The cylinder chamber is hermetically sealed and movable in a radial direction in the cylinder chamber from a contact position that can contact the cam surface to a non-contact position that does not contact the cam surface even if the cam rotates relative to the cylinder. A piston,
A suction control valve provided on the side of supplying the oil to the cylinder chamber;
The oil flow that is provided between the cylinder chamber and the suction control valve, opens with respect to the oil flow from the suction control valve toward the cylinder chamber, and flows from the cylinder chamber toward the suction control valve. A suction-side check valve that closes against
The oil is provided on the side of the cylinder chamber that discharges the oil, and opens when the oil flows from the cylinder chamber toward the discharge side. A discharge check valve that closes against the flow;
A control device for controlling opening and closing of the suction control valve;
With
The control device restricts movement of the piston when the accelerator pedal of the vehicle is not depressed and the rotational speed of the engine is located at the non-contact position when the vehicle on which the engine is mounted is decelerated. When the number of rotations is less than an allowable rotational speed, the oil is not supplied into the cylinder chamber by closing the suction control valve, and the piston is moved to the non-contact position;
A power transmission device characterized by that.

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