JP2015031312A - Power transmission mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power transmission mechanism capable of improving the transmission efficiency of power in a continuously variable transmission.SOLUTION: A power transmission mechanism 5 is interposed between an engine 2 and a CVT input shaft 34. The power transmission mechanism 5 comprises a planetary gear mechanism 51. The power generated by the engine 2 is transmitted from an E/G output shaft 21 to a sun gear 53 via a carrier 55 of the planetary gear mechanism 51 and rotates the sun gear 53 and the CVT input shaft 34 of a continuously variable transmission 3. By changing rotation speed of a ring gear 56, the power transmitted from the carrier 55 to the sun gear 53 can be changed in speed. Accordingly, by operating the engine 2 at the rotation speed of high combustion efficiency and transmitting the rotation speed of the E/G output shaft 21 to the CVT input shaft 34 while changing the rotation speed to rotation speed suited for the continuously variable transmission 3, the transmission efficiency of power in the continuously variable transmission 3 can be improved.

Description

  The present invention relates to a power transmission mechanism that transmits power.

  Vehicles such as automobiles are equipped with a gear type stepped transmission or continuously variable transmission (CVT) in order to shift engine power and transmit it to wheels.

  CVT is a transmission capable of continuously changing a gear ratio. Various types of CVTs have been put into practical use for vehicles, but in automobiles, a metal belt type CVT in which a metal belt is wound around two variable diameter pulleys is the mainstream.

  In CVT, it is possible to change gears at an optimum gear ratio according to the running condition of the automobile, and it is possible to realize smooth running. In addition, there is no shift shock that occurs during a shift by the stepped transmission. In addition, there is an advantage that the engine can be operated in a high-efficiency rotation range (minimum fuel consumption rate region), thereby reducing fuel consumption.

JP 2011-21664 A

  However, CVT has a disadvantage that power transmission efficiency is worse than that of a gear type stepped transmission. For example, in a metal belt type CVT, the variable diameter pulley is pressed against the metal belt by hydraulic pressure, and power is transmitted from the input shaft (primary pulley) to the output shaft (secondary pulley) by the frictional force between the metal belt and the variable diameter pulley. Is done. Therefore, a transmission loss due to slip between the metal belt and the variable diameter pulley occurs. Further, in the metal belt type CVT, there is also a loss due to generation of hydraulic pressure.

  The power transmission efficiency in CVT depends on the rotational speed of the input shaft, the magnitude of power (torque) input to the input shaft, and the gear ratio. For example, if the multiplication value of the rotational speed of the input shaft and the torque is constant, the power transmission efficiency decreases as the rotational speed increases and the torque decreases. Therefore, the power transmission efficiency in the CVT is particularly bad when traveling under high rotation and low load (during high-speed traveling).

  An object of the present invention is to provide a power transmission mechanism that can improve power transmission efficiency in a continuously variable transmission.

  In order to achieve the above object, a power transmission mechanism according to the present invention is used in a vehicle equipped with an engine and a continuously variable transmission, and is a power transmission mechanism that transmits power between the engine and the continuously variable transmission. A planetary gear mechanism having a first rotating element, a second rotating element to which the output shaft of the engine is connected, and a third rotating element to which the input shaft of the continuously variable transmission is connected, and the first rotating element, And a rotation speed changing means for changing the rotation speed of the first rotation element and shifting the power transmitted from the second rotation element to the third rotation element.

  According to this configuration, the power generated by the engine is transmitted from the engine output shaft to the third rotation element via the second rotation element, and rotates the third rotation element and the input shaft of the continuously variable transmission. By changing the rotation speed of the first rotating element, the power transmitted from the second rotating element to the third rotating element can be changed. Therefore, by operating the engine at a rotational speed with high combustion efficiency, changing the rotational speed of the output shaft of the engine to a rotational speed suitable for the continuously variable transmission, and transmitting it to the input shaft of the continuously variable transmission, The power transmission efficiency in the continuously variable transmission can be improved. As a result, the running fuel consumption of the vehicle can be improved.

  Further, the rotation direction of the third rotation element can be reversed by the level of the rotation speed of the first rotation element with respect to the rotation speed of the second rotation element. Then, forward and reverse of the vehicle can be switched by reversing the rotation direction of the third rotation element. Therefore, the forward / reverse switching mechanism that is essential for a vehicle equipped with a continuously variable transmission can be eliminated, and the cost of the vehicle can be reduced.

  The planetary gear mechanism may incorporate a forward / reverse switching mechanism for switching forward / reverse of the vehicle.

  The rotation speed changing means may be a motor generator.

  The motor generator may be driven as a motor or may be driven as a generator (generator). For example, when the vehicle is accelerated, the motor generator is driven as a motor, whereby the power from the motor generator is transmitted to the first rotating element, and the engine can be assisted by the power. Further, when the vehicle is decelerated, the motor generator is driven as a generator, whereby the rotation of the first rotating element can be regenerated into electric power. Therefore, drivability and fuel consumption can be improved.

  The output shaft of the engine is connected to the second rotating element via a clutch that is disconnected when the input shaft of the torque converter or continuously variable transmission is stopped, and power is transmitted between the motor generator and the first rotating element. A first clutch mechanism for transmitting / interrupting power, and a second clutch mechanism for bypassing the torque converter or clutch between the motor generator and the engine output shaft to transmit / cut power. You may go out.

  When the engine is stopped and the transmission of power between the motor generator and the first rotating element is interrupted by the first clutch mechanism, the power from the motor generator is applied to the output shaft of the engine by the second clutch mechanism. By being transmitted, the engine output shaft can be rotated to start the engine. That is, the motor generator can function as an engine starter. Therefore, a starter can be omitted, and the cost of the vehicle can be reduced.

  According to the present invention, it is possible to shift the power transmitted from the output shaft of the engine to the input shaft of the continuously variable transmission. Therefore, by operating the engine at a rotational speed with high combustion efficiency, changing the rotational speed of the output shaft of the engine to a rotational speed suitable for the continuously variable transmission and transmitting it to the input shaft of the continuously variable transmission, The power transmission efficiency in the continuously variable transmission can be improved. As a result, the running fuel consumption of the vehicle can be improved.

It is a figure which shows notionally the structure of the drive system of the vehicle incorporating the power transmission mechanism which concerns on 1st Embodiment of this invention. It is a collinear diagram which shows the relationship of the rotation speed of the sun gear of a power transmission mechanism, a carrier, and a ring gear. FIG. 5 is a collinear diagram showing the relationship among the rotational speeds of a sun gear, a carrier, and a ring gear of a power transmission mechanism when the vehicle is moving backward. It is a figure which shows notionally the structure of the drive system of the vehicle incorporating the power transmission mechanism which concerns on 2nd Embodiment of this invention. It is a figure which shows notionally the modification of the structure shown by FIG. It is a figure which shows notionally the structure of the drive system of the vehicle incorporating the power transmission mechanism which concerns on 3rd Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

<First Embodiment>

  FIG. 1 is a diagram conceptually showing the configuration of a drive system of a vehicle 1 in which a power transmission mechanism 5 according to a first embodiment of the present invention is incorporated.

  The vehicle 1 is an automobile that uses an engine (E / G) 2 as a power source. The vehicle 1 is equipped with a continuously variable transmission (CVT) 3.

  The continuously variable transmission 3 is, for example, a metal belt CVT, and includes a primary pulley 31 and a secondary pulley 32 that are variable diameter pulleys, and a metal belt 33 wound around the primary pulley 31 and the secondary pulley 32. Yes. A CVT input shaft 34 and a CVT output shaft 35 are directly connected to the centers of the primary pulley 31 and the secondary pulley 32 so as not to be relatively rotatable.

  In this specification, two rotating bodies such as shafts and gears are directly connected, and even if another rotating body is interposed between the two rotating bodies, these rotating bodies are common. In the case of integrally rotating around the rotation axis, the connection is included in the concept of “direct connection”, assuming that such connection is also substantially direct connection.

  The power input to the CVT input shaft 34 (rotation of the CVT input shaft 34) depends on the groove width (diameter) of the primary pulley 31 and the secondary pulley 32 via the primary pulley 31, the metal belt 33, and the secondary pulley 32. The gear is changed at a gear ratio and transmitted to the CVT output shaft 35. The power transmitted to the CVT output shaft 35 is transmitted to a drive shaft (not shown) extending left and right from the differential gear via a final gear and a differential gear (not shown). As a result, the left and right drive shafts rotate, and drive wheels (not shown) connected to the drive shafts rotate.

  The output shaft 21 of the engine 2 (hereinafter referred to as “E / G output shaft 21”) and the CVT input shaft 34 are disposed on the same rotational axis. A forward / reverse switching mechanism 4 and a power transmission mechanism 5 are interposed between the E / G output shaft 21 and the CVT input shaft 34.

  The forward / reverse switching mechanism 4 includes a planetary gear mechanism 41, a forward clutch 42, and a reverse brake 43.

  The planetary gear mechanism 41 includes a sun gear 44, a plurality of planetary gears 45, a carrier 46 and a ring gear 47.

  The sun gear 44 is provided so as to be rotatable together with the E / G output shaft 21.

  The plurality of planetary gears 45 are arranged around the sun gear 44 at equal angular intervals. Each planetary gear 45 meshes with the sun gear 44.

  The carrier 46 holds each planetary gear 45 so as to be rotatable, and is provided so as to be rotatable around the same rotation axis as the E / G output shaft 21 (sun gear 44).

  The ring gear 47 has an annular shape that collectively surrounds the plurality of planetary gears 45, and is provided to be rotatable about the same rotational axis as the E / G output shaft 21 (sun gear 44). Gear teeth are formed on the inner peripheral surface of the ring gear 47, and the gear teeth mesh with the planetary gears 45.

  The forward clutch 42 is interposed between the E / G output shaft 21 and the carrier 46. When the forward clutch 42 is engaged, the E / G output shaft 21 and the carrier 46 are connected, and they can rotate integrally. When the forward clutch 42 is disengaged, the E / G output shaft 21 and the carrier 46 are separated, and they can be rotated individually.

  The reverse brake 43 stops the rotation of the carrier 46 in the operating state (on) and allows the rotation of the carrier 46 in the released state (off).

  The power transmission mechanism 5 includes a planetary gear mechanism 51 and a motor generator 52.

  The planetary gear mechanism 51 includes a sun gear 53, a plurality of planetary gears 54, a carrier 55, and a ring gear 56.

  The CVT input shaft 34 is directly connected to the center of the sun gear 53 so as not to be relatively rotatable.

  The plurality of planetary gears 54 are arranged at equiangular intervals around the sun gear 53. Each planetary gear 54 meshes with the sun gear 53.

  The carrier 55 holds each planetary gear 54 rotatably. The carrier 55 is connected to the ring gear 47 of the planetary gear mechanism 41 via a connecting shaft 57 extending on the same axis as the E / G output shaft 21, and rotates together with the ring gear 47 around the connecting shaft 57. It is provided as possible.

  The ring gear 56 has an annular shape that collectively surrounds the plurality of planetary gears 54, and is provided to be rotatable about the same rotational axis as the sun gear 53 and the carrier 55. Gear teeth are formed on the inner and outer peripheral surfaces of the ring gear 56. The gear teeth on the inner peripheral surface of the ring gear 56 are in mesh with the planetary gears 54.

  The motor generator 52 has both functions of a motor and a generator (generator). The motor generator 52 is arranged such that its rotating shaft 58 (hereinafter referred to as “M / G shaft 58”) extends in parallel with the E / G output shaft 21. An M / G gear 59 is held on the M / G shaft 58 so as not to be relatively rotatable. The M / G gear 59 meshes with the gear teeth on the outer peripheral surface of the ring gear 56.

  The vehicle 1 is equipped with an oil pump 6. The pump shaft of the oil pump 6 is provided coaxially with the connecting shaft 57. Accordingly, when the connecting shaft 57 rotates, the pump shaft of the oil pump 6 rotates (the oil pump 6 operates), and the oil pump 6 generates hydraulic pressure. The hydraulic pressure generated by the oil pump 6 is used as a hydraulic pressure for the primary pulley 31 and the secondary pulley 32 of the continuously variable transmission 3 to press the metal belt 33 and as an operating hydraulic pressure for the forward clutch 42 and the reverse brake 43.

  FIG. 2 is a collinear diagram showing the rotational speed relationship between the sun gear 53 (CVT input shaft 34), the carrier 55 (E / G output shaft 21), and the ring gear 56 (M / G shaft 58) of the power transmission mechanism 5. .

  When the vehicle 1 moves forward, the forward clutch 42 is engaged and the reverse brake 43 is released. Therefore, the sun gear 44 and the carrier 46 of the forward / reverse switching mechanism 4 are rotated together by the power generated by the engine 2. At this time, the planetary gear 45 revolves without rotating, power is input from the planetary gear 45 to the ring gear 47, and the ring gear 47, the connecting shaft 57, and the carrier 55 of the power transmission mechanism 5 are connected to the E / G output shaft 21 (sun gear 44). Rotate in the same direction.

  When the ring gear 56 rotates in the same direction as the carrier 55 at the same rotational speed, the sun gear 53 rotates in the same direction as the E / G output shaft 21 integrally with the carrier 55 and the ring gear 56. In addition, the CVT input shaft 34 rotates in the same direction as the E / G output shaft 21 together with the sun gear 53. When the CVT input shaft 34 rotates in the same direction as the E / G output shaft 21, the rotation is transmitted to the CVT output shaft 35 via the primary pulley 31, the metal belt 33 and the secondary pulley 32, and the CVT output shaft 35 is It rotates in the same direction as the G output shaft 21. At this time, the drive wheels rotate in the forward direction of the vehicle 1.

  For example, as indicated by a solid line in FIG. 2, the rotational speed of the engine 2 (E / G rotational speed), that is, the rotational speed of the carrier 55 is kept constant, and the rotational speed of the ring gear 56 is higher than the rotational speed of the carrier 55. Then, since the rotation of the carrier 55 is delayed from the rotation of the ring gear 56, each planetary gear 54 rotates in the same direction as the carrier 55 and the ring gear 56 due to the difference in relative rotation speed. The rotation direction of the planetary gear 54 is opposite to the rotation direction of the sun gear 53. Therefore, the rotation speed of the sun gear 53 decreases and the rotation speed of the CVT input shaft 34 decreases.

  On the contrary, as indicated by a broken line in FIG. 2, if the rotation speed of the ring gear 56 is decreased below the rotation speed of the carrier 55 while the rotation speed of the engine 2 is constant, the rotation of the carrier 55 is caused by the rotation of the ring gear 56. Therefore, each planetary gear 54 rotates in the opposite direction to the carrier 55 and the ring gear 56 due to the difference in relative rotational speed. The rotation direction of the planetary gear 54 is the same as the rotation direction of the sun gear 53. Therefore, the rotation speed of the sun gear 53 increases and the rotation speed of the CVT input shaft 34 increases.

  The rotational speed of ring gear 56 can be changed by control of motor generator 52. That is, the rotational speed of the ring gear 56 can be changed by controlling the motor generator 52 as a motor or a generator to change the rotational speed of the M / G shaft 58.

  In the planetary gear mechanism 51, by changing the gear ratio between the sun gear 53 and the planetary gear 54 and / or the gear ratio between the planetary gear 54 and the ring gear 56, the increase / decrease in the rotation speed of the sun gear 53 with respect to the increase / decrease in the rotation speed of the ring gear 56. , That is, the slope of the straight line in the alignment chart shown in FIG.

  FIG. 3 shows the relationship between the sun gear 53 (CVT input shaft 34), the carrier 55 (E / G output shaft 21) and the rotation speed (M / G shaft 58) of the power transmission mechanism 5 when the vehicle 1 moves backward. FIG.

  When the rotational speed of the motor generator 52 is increased and the rotational speed of the ring gear 56 is increased to a predetermined rotational speed or more, the rotational direction of the sun gear 53 is reversed as shown in FIG. 3, and the sun gear 53 and the CVT input shaft 34 are It rotates in the direction opposite to the E / G output shaft 21. When the CVT input shaft 34 rotates in the opposite direction to the E / G output shaft 21, the rotation is transmitted to the CVT output shaft 35 via the primary pulley 31, the metal belt 33 and the secondary pulley 32, and the CVT output shaft 35 is It rotates in the opposite direction to the G output shaft 21. Therefore, the drive wheel rotates in the backward direction of the vehicle 1 and the vehicle 1 moves backward.

  In the vehicle 1, the motor generator 52 can function as a starter for the engine 2. That is, when the engine 2 is started, the forward clutch 42 is disconnected, and the sun gear 44 of the planetary gear mechanism 41 is separated from the carrier 46 so as to be rotatable. Further, the reverse brake 43 is actuated to brake the carrier 46. In this state, the motor generator 52 is controlled, and the motor generator 52 is driven as a motor. The M / G shaft 58 is rotated by the power generated by the motor generator 52, and the rotation is transmitted to the ring gear 56 of the planetary gear mechanism 51 via the M / G gear 59. At this time, the vehicle 1 is stopped, the CVT input shaft 34 is stopped, and the sun gear 53 is stopped. Therefore, when the ring gear 56 rotates, power is input from the ring gear 56 to each planetary gear 54, and the planetary gear 54 rotates. While revolving around the sun gear 53. With the revolution of the planetary gear 54, the carrier 55, the connecting shaft 57, and the ring gear 47 of the planetary gear mechanism 41 rotate. Since the oil pump 6 is actuated by the rotation of the connecting shaft 57, the forward clutch 42 and the reverse brake 43 can be favorably actuated by the hydraulic pressure generated by the oil pump 6. Since the carrier 46 is braked, when the ring gear 47 rotates, the planetary gears 45 rotate without changing the position of the sun gear 44 in the circumferential direction by the power input from the ring gear 47 to the planetary gears 45. As the planetary gear 45 rotates, power is input from the planetary gear 45 to the sun gear 44, and the sun gear 44 and the E / G output shaft 21 are rotated by the power. The cranking of the engine 2 is achieved by the rotation of the E / G output shaft 21.

  As described above, the power generated by the engine 2 is transmitted from the E / G output shaft 21 to the sun gear 53 via the carrier 55 of the planetary gear mechanism 51, and the sun gear 53 and the CVT input shaft 34 of the continuously variable transmission 3 are transmitted. Rotate. By changing the rotational speed of the ring gear 56, the power transmitted from the carrier 55 to the sun gear 53 can be changed. Therefore, by operating the engine 2 at a rotational speed with high combustion efficiency, the rotational speed of the E / G output shaft 21 is changed to a rotational speed suitable for the continuously variable transmission 3 and transmitted to the CVT input shaft 34. The power transmission efficiency in the continuously variable transmission 3 can be improved. As a result, the traveling fuel consumption of the vehicle 1 can be improved.

  Further, the rotational direction of the sun gear 53 can be reversed due to the rotational speed of the ring gear 56 with respect to the rotational speed of the carrier 55. Then, by reversing the rotational direction of the sun gear 53, the vehicle 1 can be switched between forward and reverse without using the forward / reverse switching mechanism 4. Therefore, the forward / reverse switching mechanism 4 can be omitted, and the cost of the vehicle 1 can be reduced.

  Further, in a state where the forward clutch 42 is engaged and the reverse brake 43 is released, the engine 2 is stopped and the motor generator 52 is driven as a motor, so that the vehicle 1 is driven only by the power generated by the motor generator 52. You can reverse. Since the engine 2 can be stopped when the vehicle 1 moves backward, fuel consumption can be improved.

  Of course, as described above, the engine 2 may be operated when the vehicle 1 is moving backward. In this case, the power generated by the engine 2 is added to the power generated by the motor generator 52, so that the backward driving force of the vehicle 1 increases. To do. Therefore, a sufficient backward driving force can be exhibited, for example, when climbing up due to the backward movement of the vehicle 1.

  Furthermore, since forward / reverse of the vehicle 1 can be switched without changing gears, there is no occurrence of shock due to gear changes. Moreover, compared with the structure which switches forward / reverse of the vehicle 1 by switching gears, the forward / reverse switching response is excellent.

  In order to change the rotation speed of the ring gear 56, a motor generator 52 is provided. The motor generator 52 may be driven as a motor or may be driven as a generator. When the motor generator 52 is driven as a generator, the electric power generated by the motor generator 52 is stored in a battery (not shown) and used to drive auxiliary machinery. When the vehicle 1 is accelerated, the motor generator 52 is driven as a motor, whereby the power from the motor generator 52 is transmitted to the ring gear 56, and the engine 2 can be assisted by the power. Further, when the vehicle 1 is decelerated, the motor generator 52 is driven as a generator, whereby the rotation of the ring gear 56 can be regenerated into electric power. Therefore, drivability and fuel consumption can be improved.

  Further, the motor generator 52 can function as a starter for the engine 2. Therefore, a starter can be omitted, and the cost of the vehicle 1 can be further reduced.

  Further, the configuration in which the power from the motor generator 52 is input to the ring gear 56 is different from the configuration in which the power from the motor generator 52 is input to the sun gear 53 or the carrier 55 outside the space where the planetary gear mechanism 51 is disposed. A motor generator 52 can be arranged. Therefore, the planetary gear mechanism 51 (the space in which the planetary gear mechanism 51 is disposed) can be reduced in size. Further, the degree of freedom of arrangement of motor generator 52 is high, and it is easy to secure a space in which motor generator 52 is arranged.

Second Embodiment

  FIG. 4 is a diagram conceptually showing the configuration of the drive system of the vehicle 101 in which the power transmission mechanism 105 according to the second embodiment of the present invention is incorporated.

  The vehicle 101 is an automobile that uses the engine 102 as a power source. The vehicle 101 is equipped with a continuously variable transmission 103.

  The continuously variable transmission 103 is, for example, a metal belt CVT, and includes a primary pulley 131 and a secondary pulley 132 that are variable diameter pulleys, and a metal belt 133 wound around the primary pulley 131 and the secondary pulley 132. Yes. A CVT input shaft 134 and a CVT output shaft 135 are directly connected to the centers of the primary pulley 131 and the secondary pulley 132 so as not to be relatively rotatable.

  The power input to the CVT input shaft 134 (rotation of the CVT input shaft 134) depends on the groove width (diameter) of the primary pulley 131 and the secondary pulley 132 via the primary pulley 131, the metal belt 133, and the secondary pulley 132. The gear is changed at a gear ratio and transmitted to the CVT output shaft 135. The power transmitted to the CVT output shaft 135 is transmitted to a drive shaft (not shown) extending left and right from the differential gear via a final gear and a differential gear (not shown). As a result, the left and right drive shafts rotate, and drive wheels (not shown) connected to the drive shafts rotate.

  A torque converter 104 and a power transmission mechanism 105 are interposed between the engine 102 and the CVT input shaft 134.

  The input shaft of torque converter 104 is directly connected to output shaft 121 of engine 102 (hereinafter referred to as “E / G output shaft 121”).

  The power transmission mechanism 105 includes a planetary gear mechanism 151, a motor generator 152, a first clutch mechanism 153, and a second clutch mechanism 154.

  The planetary gear mechanism 151 includes a sun gear 155, a plurality of planetary gears 156, a carrier 157, and a ring gear 158.

  The sun gear 155 is provided so as to be rotatable about the same rotation axis as the E / G output shaft 121. A CVT input shaft 134 is directly connected to the rotation center of the sun gear 155 so as not to be relatively rotatable.

  The plurality of planetary gears 156 are arranged at equiangular intervals around the sun gear 155. Each planetary gear 156 meshes with the sun gear 155.

  The carrier 157 holds each planetary gear 156 rotatably. The output shaft of the torque converter 104 is directly connected to the carrier 157, and the carrier 157 is provided so as to be able to rotate integrally with the output shaft of the torque converter 104 around the output shaft of the torque converter 104.

  The ring gear 158 has an annular shape that collectively surrounds the plurality of planetary gears 156, and is provided to be rotatable about the same rotation axis as the sun gear 155 and the carrier 157. Gear teeth are formed on the inner and outer peripheral surfaces of the ring gear 158. The gear teeth on the inner peripheral surface of the ring gear 158 mesh with each planetary gear 156.

  The motor generator 152 has both functions of a motor and a generator (generator). A rotation shaft 159 (hereinafter referred to as “M / G shaft 159”) of the motor generator 152 extends to both sides of the motor generator 152, and the M / G shaft 159 has an E / G output shaft 121. It is arrange | positioned so that it may extend in parallel.

  First clutch mechanism 153 includes a sun gear 160, a plurality of planetary gears 161, a carrier 162, a ring gear 163, and a direct coupling clutch 164.

  The sun gear 160 is provided to be rotatable about the same rotation axis as the M / G shaft 159. An M / G shaft 159 extending from the motor generator 152 to one side is directly connected to the rotation center of the sun gear 160 so as not to be relatively rotatable.

  The plurality of planetary gears 161 are arranged at equiangular intervals around the sun gear 160. Each planetary gear 161 meshes with the sun gear 160.

  The carrier 162 holds each planetary gear 161 rotatably. The carrier 162 is provided to be rotatable about the same rotation axis as the M / G shaft 159.

  The ring gear 163 has an annular shape that collectively surrounds the plurality of planetary gears 161, and is provided to be rotatable about the same rotation axis as the sun gear 160 and the carrier 162, that is, the same rotation axis as the M / G shaft 159. ing. Gear teeth are formed on the inner and outer peripheral surfaces of the ring gear 163. The gear teeth on the inner peripheral surface of the ring gear 163 mesh with each planetary gear 161. The gear teeth on the outer peripheral surface of the ring gear 163 mesh with the gear teeth on the outer peripheral surface of the ring gear 158 of the planetary gear mechanism 151.

  The direct clutch 164 is interposed between the M / G shaft 159 and the carrier 162. When the direct coupling clutch 164 is engaged, the M / G shaft 159 and the carrier 162 are directly coupled so that they can rotate together. When the direct coupling clutch 164 is disengaged, the M / G shaft 159 and the carrier 162 are separated and can be rotated individually.

  Second clutch mechanism 154 includes a sun gear 165, a plurality of planetary gears 166, a carrier 167, a ring gear 168, a flywheel 169 and a brake 170.

  The sun gear 165 is provided to be rotatable about the same rotation axis as the M / G shaft 159. An M / G shaft 159 extending from the motor generator 152 to the other side (the side opposite to the first clutch mechanism 153) is directly connected to the rotation center of the sun gear 165 so as not to be relatively rotatable.

  The plurality of planetary gears 166 are arranged at equiangular intervals around the sun gear 165. Each planetary gear 166 meshes with the sun gear 165.

  The carrier 167 holds each planetary gear 166 rotatably. The carrier 167 is provided to be rotatable about the same rotation axis as the M / G shaft 159.

  The ring gear 168 has an annular shape that collectively surrounds the plurality of planetary gears 166, and is provided so as to be rotatable about the same rotation axis as the sun gear 165 and the carrier 167, that is, the same rotation axis as the M / G shaft 159. ing. Gear teeth are formed on the inner and outer peripheral surfaces of the ring gear 168. The gear teeth on the inner peripheral surface of the ring gear 168 mesh with each planetary gear 166.

  The flywheel 169 is held on the E / G output shaft 121. Gear teeth (outer ring gear) are formed on the outer periphery of the flywheel 169. The gear teeth mesh with the gear teeth on the outer peripheral surface of the ring gear 168.

  The brake 170 is a brake that stops the rotation of the carrier 167 in the operating state (on) and allows the rotation of the carrier 167 in the released state (off).

  The vehicle 101 is equipped with an oil pump 106. The pump shaft of the oil pump 106 is provided coaxially with the output shaft of the torque converter 104. Thus, when the output shaft of the torque converter 104 rotates, the pump shaft of the oil pump 106 rotates and the oil pump 106 generates hydraulic pressure. The hydraulic pressure generated by the oil pump 106 is used, for example, as the hydraulic pressure for the primary pulley 131 and the secondary pulley 132 of the continuously variable transmission 103 to press the metal belt 133.

  The power generated by the engine 102 is amplified by the torque converter 104 and transmitted to the output shaft of the torque converter 104. With this power, the output shaft of the torque converter 104 and the carrier 157 of the planetary gear mechanism 151 rotate in the same direction as the E / G output shaft 121.

  When the vehicle 101 moves forward, the direct coupling clutch 164 is engaged and the brake 170 is released. Therefore, the sun gear 160 of the first clutch mechanism 153 and the carrier 162 rotate together with the M / G shaft 159 by the power generated by the motor generator 152. At this time, the planetary gear 161 revolves without rotating, power is input from the planetary gear 161 to the ring gear 163, and the ring gear 163 rotates. The rotation of the ring gear 163 is transmitted to the ring gear 158 of the planetary gear mechanism 151 to rotate the ring gear 158.

  At this time, the sun gear 165 of the second clutch mechanism 154 rotates together with the M / G shaft 159 by the power generated by the motor generator 152. As each sun gear 165 rotates, each planetary gear 166 rotates. However, since the brake 170 is released, the carrier 167 rotates and the rotation of the sun gear 165 is not transmitted to the ring gear 168.

  When the ring gear 158 rotates in the same direction as the carrier 157 at the same rotational speed, the sun gear 155 rotates in the same direction as the E / G output shaft 121 integrally with the carrier 157 and the ring gear 158. In addition, the CVT input shaft 134 rotates in the same direction as the E / G output shaft 121 together with the sun gear 155. When the CVT input shaft 134 rotates in the same direction as the E / G output shaft 121, the rotation is transmitted to the CVT output shaft 135 via the primary pulley 131, the metal belt 133, and the secondary pulley 132, and the CVT output shaft 135 is transmitted to the E / G output shaft 135. It rotates in the same direction as the G output shaft 121. At this time, the drive wheels rotate in the forward direction of the vehicle 101.

  When the rotation speed of the ring gear 158 is increased more than the rotation speed of the carrier 157, the rotation of the carrier 157 is delayed from the rotation of the ring gear 158. Therefore, due to the difference in relative rotation speed, each planetary gear 156 has the carrier 157 and the ring gear 158. And rotate in the same direction. The rotation direction of the planetary gear 156 is opposite to the rotation direction of the sun gear 155. Therefore, the rotation speed of the sun gear 155 decreases, and the rotation speed of the CVT input shaft 134 decreases.

  On the other hand, when the rotation speed of the ring gear 158 is lowered below the rotation speed of the carrier 157, the rotation of the carrier 157 advances more than the rotation of the ring gear 158, so that each planetary gear 156 is driven by the difference in relative rotation speed. And it rotates in the opposite direction to the ring gear 158. The rotation direction of the planetary gear 156 is the same as the rotation direction of the sun gear 155. Therefore, the rotation speed of the sun gear 155 increases and the rotation speed of the CVT input shaft 134 increases.

  When the number of rotations of motor generator 152 is increased and the number of rotations of ring gear 158 rises above a predetermined number of rotations, the direction of rotation of sun gear 155 is reversed, and sun gear 155 and CVT input shaft 134 are opposite to E / G output shaft 121. Rotate in the direction. When the CVT input shaft 134 rotates in the direction opposite to the E / G output shaft 121, the rotation is transmitted to the CVT output shaft 135 via the primary pulley 131, the metal belt 133, and the secondary pulley 132, and the CVT output shaft 135 is transmitted to the E / G output shaft 135. It rotates in the opposite direction to the G output shaft 121. Therefore, the drive wheel rotates in the backward direction of the vehicle 101, and the vehicle 101 moves backward.

  The rotational speed of ring gear 158 can be changed by control of motor generator 152. That is, by controlling the motor generator 152 as a motor or a generator and changing the rotation speed of the ring gear 163 of the first clutch mechanism 153, the rotation speed of the ring gear 158 can be changed.

  In the planetary gear mechanism 151, by changing the gear ratio between the sun gear 155 and the planetary gear 156 and / or the gear ratio between the planetary gear 156 and the ring gear 158, the increase or decrease in the rotation speed of the sun gear 155 with respect to the increase or decrease in the rotation speed of the ring gear 158. The ratio of can be changed.

  When the engine 102 is started, the brake 170 is operated and the direct clutch 164 is disconnected. Then, motor generator 152 is controlled, and motor generator 152 is driven as a motor. The sun gear 165 of the second clutch mechanism 154 rotates together with the M / G shaft 159 by the power generated by the motor generator 152. Since the carrier 167 is braked, each planetary gear 166 rotates as the sun gear 165 rotates, and power is transmitted from each planetary gear 166 to the ring gear 168. When the ring gear 168 rotates, the rotation is transmitted to the E / G output shaft 121 via the flywheel 169, the E / G output shaft 21 rotates, and cranking of the engine 102 is achieved.

  At this time, the sun gear 160 of the first clutch mechanism 153 rotates together with the M / G shaft 159 by the power generated by the motor generator 152. Each planetary gear 161 rotates as the sun gear 160 rotates. However, since the direct coupling clutch 164 is disconnected, the carrier 162 rotates and the rotation of the sun gear 160 is not transmitted to the ring gear 163.

  Therefore, even in the configuration shown in FIG. 4, the same operational effects as the configuration shown in FIG. 1 can be achieved.

  As shown in FIG. 5, instead of the first clutch mechanism 153 shown in FIG. 4, a first clutch mechanism 173 configured to include a first coupling gear 171 and a first clutch 172 is provided, and the second clutch Instead of the mechanism 154, a second clutch mechanism 176 configured to include the second coupling gear 174 and the second clutch 175 may be provided.

  An M / G shaft 159 extending from the motor generator 152 to one side is directly connected to the rotation center of the first connection gear 171 so as not to be relatively rotatable. The first connecting gear 171 meshes with the gear teeth on the outer peripheral surface of the ring gear 158 of the planetary gear mechanism 151.

  First clutch 172 is interposed in the middle of M / G shaft 159 extending from motor generator 152 to one side.

  An M / G shaft 159 extending from the motor generator 152 to the other side is directly connected to the rotation center of the second connection gear 174 so as not to be relatively rotatable. The second connection gear 174 meshes with gear teeth (outer ring gear) on the outer peripheral surface of the flywheel 169 held by the E / G output shaft 121.

  Second clutch 175 is interposed in the middle of M / G shaft 159 extending from motor generator 152 to the other side.

  In the configuration shown in FIG. 5, the first clutch 172 is engaged and the second clutch 175 is disconnected when the vehicle 101 moves forward, and the second clutch 175 is engaged when the engine 102 is started. Thus, the first clutch 172 is disengaged, so that the same operational effects as the configuration shown in FIG. 4 can be obtained.

<Third Embodiment>

  FIG. 6 is a diagram conceptually showing the configuration of the drive system of the vehicle 201 in which the power transmission mechanism 204 according to the third embodiment of the present invention is incorporated.

  A vehicle 201 is an automobile that uses an engine 202 as a power source. The vehicle 201 is equipped with a continuously variable transmission 203.

  The continuously variable transmission 203 is, for example, a metal belt CVT, and includes a primary pulley 231 and a secondary pulley 232 that are variable diameter pulleys, and a metal belt 233 wound around the primary pulley 231 and the secondary pulley 232. Yes. A CVT input shaft 234 and a CVT output shaft 235 are directly connected to the centers of the primary pulley 231 and the secondary pulley 232 so as not to be relatively rotatable.

  The power input to the CVT input shaft 234 (rotation of the CVT input shaft 234) depends on the groove width (diameter) of the primary pulley 231 and the secondary pulley 232 via the primary pulley 231, the metal belt 233, and the secondary pulley 232. The gear is changed at a gear ratio and transmitted to the CVT output shaft 235. The power transmitted to the CVT output shaft 235 is transmitted to a drive shaft (not shown) extending left and right from the differential gear via a final gear and a differential gear (not shown). As a result, the left and right drive shafts rotate, and drive wheels (not shown) connected to the drive shafts rotate.

  A power transmission mechanism 204 is interposed between the output shaft 221 of the engine 202 (hereinafter referred to as “E / G output shaft 221”) and the CVT input shaft 234.

  The power transmission mechanism 204 includes a planetary gear mechanism 241 and a motor generator 242.

  The planetary gear mechanism 241 includes a sun gear 244, a plurality of planetary gears 245, a carrier 246, a ring gear 247, and a forward / reverse switching mechanism 248.

  An E / G output shaft 221 is directly connected to the center of the sun gear 244 so as not to be relatively rotatable.

  The plurality of planetary gears 245 are arranged at equiangular intervals around the sun gear 244. Each planetary gear 245 meshes with the sun gear 244.

  The carrier 246 rotatably holds each planetary gear 245 and is rotatable about the same rotation axis as the sun gear 244 (E / G output shaft 221).

  The ring gear 247 is provided so as to be rotatable integrally with the CVT input shaft 234. The ring gear 247 has an inner peripheral surface that collectively surrounds the plurality of planetary gears 245, and gear teeth are formed on the inner peripheral surface. The gear teeth on the inner peripheral surface of the ring gear 247 mesh with each planetary gear 245.

  The forward / reverse switching mechanism 248 is a brake that stops the rotation of the carrier 246 in the operating state (on) and allows the rotation of the carrier 246 in the released state (off).

  The motor generator 242 has both functions of a motor and a generator (generator). The motor generator 242 is arranged such that its rotating shaft 251 (hereinafter, “M / G shaft 251”) extends in parallel with the E / G output shaft 221. An M / G gear 252 is held on the M / G shaft 251 so as not to be relatively rotatable. The carrier 246 of the planetary gear mechanism 241 holds a ring-shaped gear 253 centering on the rotation axis of the carrier 246. The M / G gear 252 meshes with the gear 253.

  When the vehicle 201 moves forward, the E / G output shaft 221 and the sun gear 244 rotate integrally with the power generated by the engine 202. Further, when the vehicle 201 moves forward, the forward / reverse switching mechanism (brake) 248 is released.

  When the carrier 246 rotates in the same direction as the sun gear 244 at the same rotational speed, the carrier 246 rotates in the same direction as the E / G output shaft 221 integrally with the sun gear 244. At this time, each planetary gear 245 does not rotate, and the rotation of the carrier 246 is transmitted from the planetary gear 245 to the ring gear 247 to rotate the ring gear 247 in the same direction. As a result, the ring gear 247 and the CVT input shaft 234 rotate in the same direction as the E / G output shaft 221. When the CVT input shaft 234 rotates in the same direction as the E / G output shaft 221, the rotation is transmitted to the CVT output shaft 235 via the primary pulley 231, the metal belt 233, and the secondary pulley 232, and the CVT output shaft 235 is transmitted to the E / G output shaft 235. It rotates in the same direction as the G output shaft 221. At this time, the drive wheels rotate in the forward direction of the vehicle 201.

  If the rotation speed of the engine 202, that is, the rotation speed of the sun gear 244 is kept constant, and the rotation speed of the carrier 246 is higher than the rotation speed of the sun gear 244, the rotation of the carrier 246 advances more than the rotation of the sun gear 244. Each planetary gear 245 rotates in the same direction as the carrier 246 and the ring gear 247 due to a difference in rotational speed. Therefore, the rotation speed of the ring gear 247 increases and the rotation speed of the CVT input shaft 235 increases.

  On the contrary, if the rotation speed of the carrier 246 is lowered below the rotation speed of the sun gear 244 while the rotation speed of the engine 202 is constant, the rotation of the carrier 246 is delayed from the rotation of the sun gear 244, Due to the difference, each planetary gear 245 rotates in the opposite direction to the carrier 246 and the ring gear 247. Therefore, the rotation speed of the ring gear 247 decreases and the rotation speed of the CVT input shaft 235 decreases.

  The number of rotations of carrier 246 can be changed by control of motor generator 242. That is, by controlling the motor generator 242 as a motor or a generator and changing the rotation speeds of the M / G shaft 251 and the M / G gear 252, the rotation speed of the carrier 246 can be changed.

  In the planetary gear mechanism 241, by changing the gear ratio between the planetary gear 245 and the ring gear 247, the ratio of increase / decrease in the rotation speed of the ring gear 247 to the increase / decrease in the rotation speed of the carrier 246 can be changed.

  When the vehicle 201 moves backward, the forward / reverse switching mechanism (brake) 248 is actuated to brake the carrier 246. Therefore, when the E / G output shaft 221 and the sun gear 244 rotate integrally with the power generated by the engine 202, each planetary gear 245 rotates in the opposite direction to the sun gear 244 without changing the position of the sun gear 244 in the circumferential direction. Due to the rotation of the planetary gear 245, power is transmitted from the planetary gear 245 to the ring gear 247, which causes the ring gear 247 and the CVT input shaft 234 to rotate in the opposite direction to the sun gear 244 (E / G output shaft 221). When the CVT input shaft 234 rotates in the opposite direction to the E / G output shaft 221, the rotation is transmitted to the CVT output shaft 235 via the primary pulley 231, the metal belt 233, and the secondary pulley 232, and the CVT output shaft 235 is transmitted to the E / G output shaft 235. It rotates in the opposite direction to the G output shaft 221. Therefore, the drive wheel rotates in the reverse direction of the vehicle 201.

  In this way, in the configuration shown in FIG. 6, the vehicle 201 can be switched between forward / reverse by switching the operation / release of the forward / reverse switching mechanism (brake) 248. Further, the vehicle 201 can be moved backward only by the power generated by the engine 2, and the power of the motor generator 242 is not required for the backward movement of the vehicle 201. Therefore, the motor generator 242 is not required to have a high output, and the motor generator 242 can be reduced in size and cost. In addition, the vehicle 201 can be driven backwards regardless of the state of charge of the battery that supplies power to the motor generator 242.

  Further, the power transmitted from the sun gear 244 to the ring gear 247 can be changed by changing the rotational speed of the carrier 246. Therefore, by operating the engine 202 at a rotational speed with high combustion efficiency, the rotational speed of the E / G output shaft 221 is changed to a rotational speed suitable for the continuously variable transmission 203 and transmitted to the CVT input shaft 234. The power transmission efficiency in the continuously variable transmission 203 can be improved. As a result, the traveling fuel consumption of the vehicle 201 can be improved.

  Further, by incorporating the motor generator 242 and the forward / reverse switching mechanism (brake) 248 into the planetary gear mechanism 241, the function of switching the vehicle 201 forward and backward and the rotational speed of the power input to the continuously variable transmission 203 are changed. Both functions can be achieved.

  Further, the motor generator 242 can be disposed inside the carrier 246 and the motor generator 242 can be disposed so as to overlap the sun gear 244 and the E / G output shaft 221. Thus, the motor generator 242 can be incorporated into the planetary gear mechanism 241 without increasing the size of the planetary gear mechanism 241 in the radial direction of the sun gear 244.

  The hydraulic pressure for the continuously variable transmission 203 and the brake 249 may be generated by an oil pump (not shown). The pump shaft of the oil pump is provided coaxially with the E / G output shaft 221, for example.

<Modification>

  The present invention can also be implemented in other forms.

  For example, in the first embodiment, the configuration in which the pump shaft of the oil pump 6 is provided coaxially with the connecting shaft 57 has been taken up. However, the present invention is not limited to this, and the pump shaft of the oil pump 6 may be provided coaxially with the M / G shaft 58 or may be connected to the connecting shaft 57 or the M / G shaft 58 via a gear mechanism. .

  In the second embodiment, the first clutch mechanism 153 includes the sun gear 160, the plurality of planetary gears 161, the carrier 162, the ring gear 163, and the direct coupling clutch 164, but is not limited thereto, and the ring gear of the planetary gear mechanism 151 158 may be configured with a gear meshing with gear teeth on the outer peripheral surface of 158.

  Similarly, in the second clutch mechanism 154, a gear that meshes with the flywheel 169 may be provided instead of the sun gear 165, the plurality of planetary gears 166, the carrier 167, the ring gear 168, and the brake 170.

  In the second embodiment, instead of the torque converter 104, a clutch is provided that is engaged when the vehicle 101 moves forward and updates and is disconnected when the vehicle 101 stops (when the CVT input shaft 134 stops). Also good.

  The continuously variable transmissions 3, 103, 203 are not limited to metal belt type continuously variable transmissions, but are not rubber belt type continuously variable transmissions, chain type continuously variable transmissions, toroidal continuously variable transmissions, etc. It may be a type continuously variable transmission.

  In addition, various design changes can be made to the above-described configuration within the scope of the matters described in the claims.

DESCRIPTION OF SYMBOLS 1 Vehicle 2 Engine 3 Continuously variable transmission 5 Power transmission mechanism 21 E / G output shaft (engine output shaft)
34 CVT input shaft (input shaft for continuously variable transmission)
51 planetary gear mechanism 52 motor generator (rotation speed changing means)
53 Sun gear (third rotating element)
55 Carrier (second rotating element)
56 Ring gear (first rotating element)
DESCRIPTION OF SYMBOLS 101 Vehicle 102 Engine 103 Continuously variable transmission 104 Torque converter 105 Power transmission mechanism 121 E / G output shaft (engine output shaft)
134 CVT input shaft (input shaft of continuously variable transmission)
151 planetary gear mechanism 152 motor generator (rotation speed changing means)
153 First clutch mechanism 154 Second clutch mechanism 155 Sun gear (third rotating element)
157 Carrier (second rotating element)
158 Ring gear (first rotating element)
169 Flywheel (second clutch mechanism)
173 First clutch mechanism 176 Second clutch mechanism 201 Vehicle 202 Engine 203 Continuously variable transmission 204 Power transmission mechanism 221 E / G output shaft (engine output shaft)
234 CVT input shaft (input shaft of continuously variable transmission)
241 Planetary gear mechanism 242 Motor generator (rotation speed changing means)
244 Sun gear (second rotating element)
246 carrier (first rotating element)
247 Ring gear (third rotating element)
248 Forward / reverse switching mechanism

Claims (4)

A power transmission mechanism that is used in a vehicle equipped with an engine and a continuously variable transmission and transmits power between the engine and the continuously variable transmission,
A planetary gear mechanism having a first rotating element, a second rotating element to which the output shaft of the engine is connected, and a third rotating element to which the input shaft of the continuously variable transmission is connected;
Rotational speed change means coupled to the first rotational element and changing the rotational speed of the first rotational element to shift the power transmitted from the second rotational element to the third rotational element. Transmission mechanism.   The power transmission mechanism according to claim 1, wherein the planetary gear mechanism includes a forward / reverse switching mechanism for switching forward / reverse of the vehicle.   The power transmission mechanism according to claim 1, wherein the rotation speed changing means is a motor generator. The output shaft of the engine is connected to the second rotating element via a clutch that is disconnected when the input shaft of the torque converter or the continuously variable transmission is stopped,
A first clutch mechanism for transmitting / cutting power between the motor generator and the first rotating element;
4. The power according to claim 3, further comprising a second clutch mechanism configured to bypass / transmit the torque converter or the clutch between the motor generator and the output shaft of the engine to transmit / cut off the power. Transmission mechanism.

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