JP2010179858A - Transmission system for hybrid vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transmission system for a hybrid vehicle, which has improved mountability on a vehicle by reducing the size and weight, switches from forward traveling to backward traveling without hindering smooth gear shifting through a continuously variable transmission mechanism, and reduces costs. <P>SOLUTION: The transmission system for the hybrid vehicle includes: a continuously variable transmission mechanism 7; and an input side transmission shaft 4 for transmitting rotation from one or both of an internal combustion engine 2 and a motor 3. The input side transmission shaft 4 is provided with: a forward drive gear 10 and a backward drive gear 11 that are freely rotatable; and a switching connection means 12 for connecting the forward drive gear 10 or the backward drive gear 11 to the input side transmission shaft 4. The transmission system further includes a switching control means. When the forward traveling is set instead of the backward traveling by the switching connection means 12, the switching control means forcibly synchronizes the rotation of the input side transmission shaft 4 with the rotation of the backward drive gear 11 according to the driving of the motor 3 after the forward drive gear 10 is disengaged from the input side transmission shaft 4 and before the backward drive gear 11 is connected to the input side transmission shaft 4. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a power transmission device for a hybrid vehicle including an internal combustion engine and an electric motor.

  Conventionally, as a power transmission device used in a hybrid vehicle including an internal combustion engine and an electric motor, the power transmission device includes a continuously variable transmission mechanism that has an input shaft and an output shaft and establishes a continuously variable gear stage between the two shafts. There is known a power transmission device in which the rotation of either one or both of an internal combustion engine and an electric motor is reversed by a planetary gear and transmitted to an input shaft of a continuously variable transmission mechanism to be able to move backward (see Patent Document 1 below).

  In this power transmission device, the electric motor is connected to the sun gear of the planetary gear, the carrier of the planetary gear is connected to the input shaft of the continuously variable transmission mechanism via the first clutch, and the internal combustion engine is connected to the ring gear of the planetary gear. Further, a brake for selectively fixing the carrier is provided, and a second clutch is provided between the carrier and the input shaft of the continuously variable transmission mechanism.

JP 2000-92612 A (paragraphs 0098 to 0108, FIG. 20)

  In the conventional power transmission device, when the vehicle is driven backward by the power of the internal combustion engine, the first clutch and the brake are connected, the carrier is fixed, and the sun gear is connected to the input shaft of the continuously variable transmission mechanism. The ring gear is rotated forward by the internal combustion engine. As a result, the sun gear reversely rotates and travels backward.

  By the way, in switching from the state where the vehicle is stopped (the state where the input shaft of the continuously variable transmission mechanism is not rotating) to the reverse movement, the planetary gear is stopped, so the first clutch and the brake may be connected. Although it can be performed smoothly, if the forward switching operation is performed while the forward speed of the vehicle is decreasing (before the vehicle speed becomes zero), the reverse rotation is made to the input shaft of the continuously variable transmission mechanism simultaneously with the stopping of the carrier by the brake. The driving force is applied, and there is a risk of shock or abnormal noise. For this reason, a dedicated clutch (two in total) is required for each of the forward and backward use. Moreover, in the conventional power transmission device, not only is it relatively expensive to provide a planetary gear, but if an attempt is made to separate the electric motor from the internal combustion engine to achieve a fuel-efficient hybrid, an additional clutch must be added. In addition, the weight of the power transmission device is increased, which makes it difficult to mount the power transmission device on a vehicle.

  In view of the above points, the present invention not only improves the mountability to the vehicle by reducing the size and weight of the power transmission device, but also from forward to reverse without hindering smooth shifting by the continuously variable transmission mechanism. It is an object of the present invention to provide a power transmission device for a hybrid vehicle that can be switched and that can reduce costs.

  In order to solve this problem, the present invention is a power transmission device for a hybrid vehicle including an internal combustion engine and an electric motor, and has an input shaft and an output shaft, and a stepless speed stage is established between both shafts. A continuously variable transmission mechanism that is connected to an input side transmission shaft that transmits rotation from one or both of the internal combustion engine and the electric motor, and a forward driven gear provided on the input shaft of the continuously variable transmission mechanism; A forward drive gear rotatably provided on the transmission shaft and a reverse drive gear connected to a reverse driven gear provided on the input shaft of the continuously variable transmission mechanism via an intermediate gear and rotatably provided on the input transmission shaft A switching connection means for switching and connecting the gear, the forward drive gear and the reverse drive gear to the input side transmission shaft, and the forward drive gear is disconnected from the input side transmission shaft at the time of switching from forward to reverse by the switching connection means The reverse drive gear Characterized in that it comprises a switching control means for synchronizing the forced rotation of the reverse drive gear the rotation of the input-side transmission shaft by the driving of the motor prior to being connected to the force side transmission shaft.

  In the present invention, the internal combustion engine is detachably connected to the input transmission shaft through a clutch, and the electric motor can generate electric power by rotation of the internal combustion engine transmitted through the input transmission shaft. It is connected to the input side transmission shaft.

  According to the present invention, the forward drive gear and the reverse drive gear are switched and connected to the input transmission shaft by the switching connecting means, so that the forward and reverse can be switched without using the planetary gear as in the prior art. . At this time, for example, the switching connecting means employs a synchromesh mechanism or the like, so that the forward / reverse operation and the internal combustion engine disconnection can be functioned by one clutch and can be made inexpensive. It is easy to reduce the size and weight of the transmission device, and the mounting property to the vehicle can be improved. Further, the present invention provides the switching control means, so that even if the switching operation is performed in the reverse direction while the forward speed of the vehicle is decreasing (before the vehicle speed becomes 0), the switching connection means is used. It is possible to prevent the occurrence of shock and abnormal noise at the time of switching, and to switch from forward to reverse without hindering smooth shifting by the continuously variable transmission mechanism.

  Further, in the present invention, since the internal combustion engine is detachably connected to the input transmission shaft via the clutch, for example, when the vehicle is started, the internal combustion engine is disconnected by the clutch only by the driving force of the electric motor. The clutch is connected when the rotational difference between the rotational speed of the input side transmission shaft by the electric motor and the rotational speed from the internal combustion engine is reduced, so that a shock is generated or the internal combustion engine is stopped unintentionally (so-called The engine can be smoothly driven, the clutch capacity can be reduced, and a starting clutch or torque converter can be dispensed with.

The figure which shows schematic structure of the power transmission device of this invention. The graph which shows the action | operation of the power transmission device in this embodiment. The graph for comparing with the action | operation of FIG. The figure which shows the other example in the power transmission device of FIG.

  An embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1, the power transmission device 1 of the present embodiment includes an engine 2 (internal combustion engine) and an electric motor 3 (motor / generator) as drive sources. The power transmission device 1 includes an input side transmission shaft 4 for inputting rotation from either one or both of the engine 2 and the electric motor 3, and an input shaft 5 and an output shaft 6 connected to the input side transmission shaft 4. And a continuously variable transmission mechanism 7 that establishes a continuously variable gear position between the two shafts 5 and 6.

  The input-side transmission shaft 4 is connected to a rotation transmission member 8 that is inserted into the inner space of the rotor 3b that rotates inside the stator 3a of the electric motor 3 and rotates integrally with the rotor 3b. The rotation transmission member 8 includes a clutch 9, and the clutch 9 connects the power shaft 2 a of the engine 2 to the input transmission shaft 4 in a detachable manner. Since the rotation transmission member 8 and the clutch 9 are housed in the internal space of the rotor 3b, they are compact.

  The input-side transmission shaft 4 includes a forward drive gear 10 and a reverse drive gear 11 that are rotatable, and is selectively connected to the input-side transmission shaft 4 by selectively switching the forward drive gear 10 and the reverse drive gear 11. Switching connection means 12 (synchromesh mechanism) is provided.

  A forward driven gear 13 and a reverse driven gear 14 are fixed to the input shaft 5 of the continuously variable transmission mechanism 7. The forward driven gear 13 meshes with the forward drive gear 10. The reverse driven gear 14 meshes with an intermediate gear 16 provided on a rotatable intermediate transmission shaft 15, and the intermediate gear 16 meshes with the reverse drive gear 11.

  When the vehicle travels forward, the switching connecting means 12 is moved to the left in the figure to connect the forward drive gear 10 to the input side transmission shaft 4. Thereby, the rotation of the input side transmission shaft 4 is transmitted to the input shaft 5 of the continuously variable transmission mechanism 7 via the forward drive gear 10 and the forward driven gear 13. When the vehicle is moving backward, the switching connecting means 12 is moved to the right in the drawing to connect the reverse drive gear 11 to the input transmission shaft 4. As a result, the rotation of the input side transmission shaft 4 is transmitted to the input shaft 5 of the continuously variable transmission mechanism 7 via the reverse drive gear 11, the intermediate gear 16, and the reverse driven gear 14, and rotates in the direction opposite to that during forward travel of the vehicle. Is input to the input shaft 5 of the continuously variable transmission mechanism 7.

  The continuously variable transmission mechanism 7 includes a driving pulley 17, a driven pulley 18, and an endless metal belt 19 wound between the pulleys 17 and 18.

  The driving pulley 17 includes a stationary flange 20 fixed to the input shaft 5 and a movable flange 21 that moves along the input shaft 5. The immobile flange 20 extends on the outer peripheral side of the input shaft 5 and is formed in a substantially disk shape having an inclined surface. The movable flange 21 extends on the outer peripheral side of the cylindrical portion 21a through which the input shaft 5 is inserted, and is formed in a substantially disk shape having an inclined surface. The metal belt 19 is disposed between the stationary flange 20 and the movable flange 21 of the driving pulley 17 and slides along the inclined surfaces of the flanges 20 and 21.

  The movable flange 21 of the driving pulley 17 includes a cylinder portion 22 provided in a cylindrical shape along the outer peripheral edge. The movable flange 21 is slidably accommodated in the cylinder portion 22, and a pressure chamber 23 is formed in a space between the movable flange 21 and the cylinder portion 22. The movable flange 21 reciprocates in the axial direction of the input shaft 5 by the oil pressure applied to the pressure chamber 23, and further rotates together with the input shaft 5.

  The driven pulley 18 includes a stationary flange 24 fixed to the output shaft 6 and a movable flange 25 that moves along the output shaft 6. The immovable flange 24 extends on the outer peripheral side of the output shaft 6 and is formed in a substantially disc shape having an inclined surface. The movable flange 25 extends on the outer peripheral side of the cylindrical portion 25a through which the output shaft 6 is inserted, and is formed in a substantially disk shape having an inclined surface. The metal belt 19 is disposed between the stationary flange 24 and the movable flange 25 of the driven pulley 18 and slides along the inclined surfaces of the flanges 24 and 25.

  The movable flange 25 of the driven pulley 18 includes a pressing plate 26 fixed to the output shaft 6, and is pressed in the direction of the stationary flange 24 by a coil spring (not shown) provided between the pressing plate 26 and the movable flange 25. In addition, it is designed to rotate together with the output shaft 6.

  In the continuously variable transmission mechanism 7 configured as described above, an oil pressure is applied to the pressure chamber 23 of the driving pulley 17 and the movable flange 21 moves along the axial direction of the input shaft 5. And the distance between the movable flange 21 is changed, and accordingly, the winding position of the metal belt 19 moves in the diameter direction of the driving pulley 17. And if the winding position of the metal belt 4 in the drive side pulley 17 changes, in connection with this, also in the driven pulley 18, the space | interval of the stationary flange 24 and the movable flange 25 will be changed, and winding of the metal belt 4 will be carried out. The position moves in the diameter direction of the driven pulley 18. As a result, in the continuously variable transmission mechanism 7, the transmission ratio is changed to a continuously variable.

  A final reduction drive gear 27 is provided on the output shaft 6 of the continuously variable transmission mechanism 7, and this final reduction drive gear 27 meshes with a final reduction driven gear 29 of a differential gear mechanism 28 to drive the drive shaft 30 of the vehicle. To drive.

  Further, although not shown, the power transmission device 1 detects rotation when the rotation connecting means 12 detects the rotation speed (including direction) of the input side transmission shaft 4 and the reverse drive gear 11 and the switching connection means 12 is operated. Switching control means for controlling the electric motor 3 in accordance with the rotational difference of the reverse drive gear 11 with respect to the input side transmission shaft 4 detected by the means.

  When the vehicle travels forward, the forward drive gear 10 is connected to the input transmission shaft 4 by the switching connecting means 12, whereby the input shaft 5 rotates through the forward driven gear 13. The driven gear 14 also rotates, and the reverse drive gear 11 also rotates via the intermediate gear 16. At this time, the reverse drive gear 11 is reversely rotated with respect to the forward drive gear 10 connected to the input side transmission shaft 4 as shown in FIGS. Here, when the switching operation is performed in the reverse direction while the forward speed of the vehicle is decreasing (before the vehicle speed becomes 0), when the electric motor 3 is not controlled by the switching control means, FIG. As shown, when the reverse drive gear 11 is connected to the input-side transmission shaft 4, the input-side transmission shaft 4 is suddenly reversed, and a shock or noise is generated at the time of connection.

  On the other hand, the power transmission device 1 according to the present embodiment prevents the shock and noise when the reverse drive gear 11 is connected by controlling the electric motor 3 by the switching control means. That is, as shown in FIG. 2, when the forward drive gear 10 is disconnected from the input side transmission shaft 4 by the switching connecting means 12, and the switching connecting means 12 is in a neutral state (neutral), the reverse drive by the switching connecting means 12 is performed. Prior to the connection of the gear 11 to the input side transmission shaft 4, the switching control means controls the electric motor 3 to synchronize the rotation of the input side transmission shaft 4 with the rotation of the reverse drive gear 11. In FIG. 2, the motor 3 is reversely rotated when the switching connection means 12 is neutral by the control of the switching control means so that the rotation of the input side transmission shaft 4 matches the rotation of the reverse drive gear 11. By doing so, the switching operation by the switching connection means 12 can be performed very smoothly without causing shock or noise when the reverse drive gear 11 is connected to the input side transmission shaft 4 by the switching connection means 12.

  Moreover, the power transmission device 1 can prevent the engine 2 from being dragged when the electric motor 3 is driven by separating the engine 2 with the clutch 9 in a disengaged state. Furthermore, when the engine 2 is driven with the clutch 9 in the connected state, power can be applied by the electric motor 3, and the rotation from the engine 2 is input to the electric motor 3 via the rotation transmission member 8. 3 can generate electric power. Moreover, when the vehicle is started, the vehicle is driven only by the driving force of the electric motor 3 with the engine 2 disconnected by the clutch 9, and the electric motor 3 rotates between the rotational speed of the input side transmission shaft 4 and the rotational speed of the power shaft 2a of the engine 2. By connecting the clutch 9 when the difference is reduced, it is possible to prevent the occurrence of a shock, an inadvertent stop (so-called engine stall), etc. of the engine 2 and to drive smoothly. In addition, the capacity of the clutch 9 can be reduced, and a starting clutch and a torque converter can be dispensed with.

  In the power transmission device 1 shown in FIG. 1, the input transmission shaft 4 and the rotation transmission member 8 are integrally connected. However, the configuration in which the present invention is adopted is not limited to this. For example, as shown in FIG. 4, a second clutch 31 is provided adjacent to the clutch 9 of the rotation transmission member 8 (hereinafter referred to as the first clutch 9), and the rotation transmission member is provided by the second clutch 31. 8 and the input side transmission shaft 4 may be detachably connected. According to this, when the engine 2 is decelerated at the time of deceleration and the engine 2 is started immediately after performing deceleration energy regeneration and re-acceleration is performed, the second clutch 31 is disengaged while holding the switching connection means 12. By connecting the clutch of the base 1 and transmitting the rotation of the electric motor 3 to the stopped engine 2 to start the engine 2, smooth reacceleration can be performed without generating a shock or the like. In addition, when the first clutch 9 is in a connected state and the second clutch 31 is in a disconnected state when stopped, the rotation of the electric motor 3 is stopped without rotating the input side transmission shaft 4 (without running the vehicle). The engine 2 can be started by being transmitted to the engine 2, and a starter for starting the engine 2 can be dispensed with.

  DESCRIPTION OF SYMBOLS 1 ... Power transmission device, 2 ... Engine (internal combustion engine), 3 ... Electric motor, 4 ... Input side transmission shaft, 5 ... Input shaft, 6 ... Output shaft, 7 ... Continuously variable transmission mechanism, 9 ... Clutch, 10 ... Forward drive Gear 11, reverse drive gear 12, switching connection means 13, forward driven gear 14, reverse driven gear 16, intermediate gear

Claims (2)

A power transmission device for a hybrid vehicle comprising an internal combustion engine and an electric motor,
A continuously variable transmission mechanism that has an input shaft and an output shaft and establishes a continuously variable speed between both shafts;
An input side transmission shaft for transmitting rotation from either or both of the internal combustion engine and the electric motor;
A forward drive gear connected to the forward driven gear provided on the input shaft of the continuously variable transmission mechanism and rotatably provided on the input side transmission shaft;
A reverse drive gear connected to a reverse driven gear provided on the input shaft of the continuously variable transmission mechanism via an intermediate gear and rotatably provided on the input transmission shaft;
Switching connection means for switching and connecting the forward drive gear and the reverse drive gear to the input side transmission shaft;
At the time of switching from forward to reverse by the switching connecting means, after the forward drive gear is disconnected from the input side transmission shaft, the reverse drive gear is connected to the input side transmission shaft and the input side transmission shaft is driven by the electric motor before being connected to the input side transmission shaft. And a switching control means for forcibly synchronizing the rotation of the vehicle with the rotation of the reverse drive gear. The internal combustion engine is detachably connected to the input side transmission shaft via a clutch,
2. The hybrid vehicle power transmission according to claim 1, wherein the electric motor is connected to the input-side transmission shaft so as to be able to generate electric power by rotation of the internal combustion engine transmitted through the input-side transmission shaft. apparatus.

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