JP7294911B2 - hybrid vehicle - Google Patents

Description

The present invention relates to a hybrid vehicle using a power transmission member such as a chain for power transmission between a motor and a continuously variable transmission mechanism.

In Patent Document 1, in an engine control mechanism, an intake side sprocket sharing a rotation axis with an intake camshaft, an exhaust side sprocket sharing a rotation axis with an exhaust camshaft, and a crank sprocket sharing a rotation axis with a crankshaft. , a timing chain wound around each sprocket, and a tensioner that applies a predetermined tension to the timing chain. In such a power transmission part, a tensioner maintains the tension of the chain, suppressing vibration and noise during power transmission caused by slack in the chain, and preventing poor meshing between the chain and sprocket. be able to.

JP 2017-14917 A

A power transmission member such as a chain is sometimes used to transmit power generated by a motor to a continuously variable transmission mechanism in a hybrid vehicle that employs a continuously variable transmission mechanism.

However, when a power transmission member such as a chain is used, it is necessary to provide a tensioner, which increases the cost. In addition, the friction increases when the tensioner comes into contact with the power transmission member.

SUMMARY OF THE INVENTION The present invention has been made in view of the above technical problems. It aims at suppressing the slack of a member.

According to one aspect of the present invention, a continuously variable transmission mechanism including a primary pulley, a secondary pulley, and a belt wound around the primary and secondary pulleys, and electric energy to generate power for driving a drive wheel. A hybrid vehicle comprising: a motor; and a power transmission member that is bridged between a rotating shaft of the motor and a rotating shaft of the primary pulley and that transmits power of the motor to the continuously variable transmission mechanism, wherein the primary pulley When a plane passing through the rotation axis of the motor and the rotation axis of the secondary pulley is defined as a first plane, the motor further comprising a bearing disposed on the side opposite to the side on which the rotating shaft of the secondary pulley is disposed, supporting the rotating shaft of the primary pulley and allowing radial displacement of the rotating shaft of the primary pulley. A hybrid vehicle is provided, characterized by:

According to the above aspect, when the hydraulic pressure is supplied to the continuously variable transmission, the primary pulley is pulled toward the secondary pulley. When the primary pulley moves closer to the secondary pulley with the rotating shaft of the motor positioned within the above range, the distance between the rotating shaft of the motor and the rotating shaft of the primary pulley increases, and tension is applied to the power transmission member. , sagging of the power transmission member is suppressed. Thereby, a tensioner for applying tension to the power transmission member can be eliminated.

1 is a schematic configuration diagram of a hybrid vehicle; FIG. 1 is a schematic diagram of a motor, a power transmission member, and a continuously variable transmission; FIG. It is a schematic diagram of an isolation bearing. FIG. 4 is a schematic diagram showing a state of a power transmission member according to a positional relationship between a motor and a transmission; FIG. 4 is a schematic diagram showing a state of a power transmission member according to a positional relationship between a motor and a transmission;

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a schematic configuration of a hybrid vehicle 100 (hereinafter referred to as "vehicle 100") according to an embodiment of the present invention. The vehicle 100 includes a low-voltage battery 1, a high-voltage battery 2, an engine 3, a motor generator 4 (hereinafter referred to as "MG4"), and a starter motor 5 (hereinafter referred to as "SM5") used to start the engine 3. ), a starter generator 6 (hereinafter referred to as “SG6”) used for power generation and assisting and starting the engine 3, a DC-DC converter 7, an inverter 8, a mechanical oil pump 9, and an electric oil A pump 10 , a torque converter 11 , a forward/reverse switching mechanism 12 , a continuously variable transmission mechanism 13 (hereinafter referred to as “CVT 13 ”), a differential mechanism 14 , drive wheels 18 , and a controller 20 . The torque converter 11 , the forward/reverse switching mechanism 12 and the CVT 13 constitute a transmission 30 of the vehicle 100 .

The low voltage battery 1 is a lead-acid battery with an output voltage of DC 12V. The low-voltage battery 1 is connected to a low-voltage circuit 16 together with electrical equipment 15 (automatic driving camera and sensor, navigation system, audio, air conditioner blower, etc.) that operates at SM5, 12V. The low voltage battery 1 may be a lithium ion battery with an output voltage of 12V.

The high-voltage battery 2 is a 48V DC lithium-ion battery with a higher output voltage than the low-voltage battery 1 . The output voltage of the high voltage battery 2 may be lower or higher than this, for example 30V or 100V. The high voltage battery 2 is connected to a high voltage circuit 17 together with MG4, SG6, inverter 8, electric oil pump 10 and the like.

The low voltage circuit 16 and the high voltage circuit 17 are connected via the DC-DC converter 7 . The DC-DC converter 7 has a step-up function of stepping up the 12V of the low voltage circuit 16 to 48V and outputting 48V to the high voltage circuit 17, and stepping down the 48V of the high voltage circuit 17 to 12V and supplying 12V to the low voltage circuit 16. It has a step-down function to output. As a result, the DC-DC converter 7 can output a voltage of 12V to the low voltage circuit 16 regardless of whether the engine 3 is running or stopped. Also, when the remaining capacity of the high voltage battery 2 is low, the 12 V of the low voltage circuit 16 can be boosted to 48 V and output to the high voltage circuit 17 to charge the high voltage battery 2 .

The engine 3 is an internal combustion engine that uses gasoline, light oil, or the like as fuel, and its rotational speed, torque, and the like are controlled based on commands from the controller 20 .

The torque converter 11 is provided on a power transmission path between the engine 3 and the forward/reverse switching mechanism 12, and transmits power via fluid. Further, the torque converter 11 can increase the power transmission efficiency of the driving force from the engine 3 by engaging the lockup clutch 11a when the vehicle 100 is traveling at a predetermined lockup vehicle speed or higher.

A sprocket 31 is connected to the output shaft 3 c of the engine 3 . A chain 32 for transmitting rotation between the sprocket 31 and the mechanical oil pump 9 is wound around the sprocket 31 .

When driven by the engine 3, the mechanical oil pump 9 sucks up working oil stored in an oil pan (not shown) and supplies the oil to the lockup clutch 11a, the forward/reverse switching mechanism 12 and the CVT 13 via a hydraulic circuit (not shown). do.

Electric oil pump 10 is controlled by applying a three-phase alternating current produced by inverter 8 based on commands from controller 20 . When the electric oil pump 10 is driven by receiving electric energy supplied from the high-voltage battery 2, the electric oil pump 10 sucks up hydraulic oil stored in an oil pan (not shown), and pumps the lockup clutch 11a through a hydraulic circuit (not shown). Oil is supplied to the forward switching mechanism 12 and the CVT 13 . The electric oil pump 10 is driven when the engine 3 is stopped, or when the mechanical oil pump 9 alone is insufficient to supply oil.

The forward/reverse switching mechanism 12 is provided on a power transmission path between the torque converter 11 and the CVT 13, and includes a planetary gear mechanism 12a, a forward clutch 12b, and a reverse brake 12c. When the forward clutch 12b is engaged and the reverse brake 12c is released, the rotation of the engine 3 input to the forward/reverse switching mechanism 12 via the torque converter 11 is transferred from the forward/reverse switching mechanism 12 to the CVT 13 while maintaining the rotational direction. output. Conversely, when the forward clutch 12b is released and the reverse brake 12c is engaged, the rotation of the engine 3 input to the forward/reverse switching mechanism 12 via the torque converter 11 is decelerated and the direction of rotation is reversed to switch forward/reverse. Output from mechanism 12 to CVT 13 . The hydraulic pressure required by the forward/reverse switching mechanism 12 is generated by a hydraulic circuit (not shown) using the hydraulic pressure generated by the mechanical oil pump 9 and the electric oil pump 10 as source pressure.

The CVT 13 is arranged on a power transmission path between the forward/reverse switching mechanism 12 and the differential mechanism 14, and changes the gear ratio steplessly in accordance with the vehicle speed, accelerator opening, which is the operation amount of the accelerator pedal, and the like. The CVT 13 includes a primary pulley 13a, a secondary pulley 13b, and a belt 13c wound around both pulleys. The CVT 13 changes the groove width of the primary pulley 13a and the secondary pulley 13b by hydraulic pressure, and by changing the contact radius between the primary pulley 13a and the secondary pulley 13b and the belt 13c, the gear ratio can be changed steplessly. . The hydraulic pressure required by the CVT 13 is generated by a hydraulic circuit (not shown) using hydraulic pressure generated by the mechanical oil pump 9 and the electric oil pump 10 as source pressure.

MG4 is a synchronous rotating electrical machine in which a permanent magnet is embedded in a rotor and a stator coil is wound around a stator. MG4 rotates primary pulley 13a via chain 21 as a power transmission member wound between sprocket 4b provided on rotating shaft 4a of MG4 and sprocket 13e provided on rotating shaft 13d of primary pulley 13a. It is connected to the shaft 13d. MG 4 is controlled by applying a three-phase alternating current produced by inverter 8 based on commands from controller 20 . The MG 4 operates as an electric motor that receives electrical energy supplied from the high-voltage battery 2 and drives to rotate. Power generated by the MG4 operating as an electric motor is transmitted to the rotating shaft 13d of the primary pulley 13a via the chain 21 and the sprocket 13e. Also, when the rotor receives rotational energy from the engine 3 or the drive wheels 18 via the chain 21, the sprocket 4b, and the rotating shaft 4a, the MG4 functions as a generator that generates an electromotive force at both ends of the stator coil. and the high voltage battery 2 can be charged.

SM5 is a DC motor, and is arranged so that a pinion gear 5a can be meshed with an outer peripheral gear 3b of a flywheel 3a of the engine 3. FIG. When the engine 3 is started from a cold state for the first time, electrical energy is supplied from the low voltage battery 1 to the SM 5, the pinion gear 5a is meshed with the outer peripheral gear 3b, and the flywheel 3a and further the crankshaft are rotated.

SG 6 is a synchronous rotating electric machine, is connected to the crankshaft of engine 3 via V-belt 22 , and functions as a generator when receiving rotational energy from engine 3 . The electrical energy generated in this manner is charged to the high voltage battery 2 through the inverter 8 . Further, the SG 6 operates as an electric motor that receives electric energy supplied from the high-voltage battery 2 and drives to rotate, and assists the driving force of the engine 3 . Further, SG6 is used to rotationally drive the crankshaft of the engine 3 to restart the engine 3 when restarting the engine 3 from the idling stop state.

The inhibitor switch 41 is a sensor that detects which range is selected by the selector 42 . The range detected by inhibitor switch 41 is input to controller 20 . Ranges include D (forward), R (reverse), and M (manual) as driving ranges, and P (parking) and N (neutral) as non-driving ranges.

The controller 20 is composed of one or more microcomputers having a central processing unit (CPU), a read only memory (ROM), a random access memory (RAM) and an input/output interface (I/O interface). The controller 20 corresponds to control means, and the CPU executes a program stored in ROM or RAM to control the engine 3, inverter 8 (MG4, SG6, electric oil pump 10), DC-DC converter 7, SM5, It integrally controls the lockup clutch 11a, the forward/reverse switching mechanism 12, the CVT 13, and the like.

The controller 20 selects, as running modes of the vehicle 100, an EV mode in which the MG 4 is driven by the electric energy supplied from the high-voltage battery 2 and runs only by the driving force of the MG 4, and an engine running in which the vehicle runs only by the driving force of the engine 3. a parallel HEV driving mode in which the driving force of the engine 3 and the driving force of the MG4 are used to drive the MG4; Switch between driving modes.

By the way, in the above configuration, the chain 21 as a power transmission member for transmitting the power generated from the MG4 to the primary pulley 13a of the CVT 13 is wound between the sprocket 4b of the MG4 and the sprocket 13e of the primary pulley 13a. . When the chain 21 is used as the power transmission member, a tensioner is conventionally provided to apply a predetermined tension to the chain 21. However, the provision of the tensioner increases the cost accordingly, and the tensioner contacts the chain 21. Chain friction will increase.

Therefore, in this embodiment, when the chain 21 is used as the power transmission member for transmitting the power of the MG4 to the CVT 13, instead of providing a tensioner mechanism, the MG4 is connected to the rotating shaft 13d of the primary pulley 13a and the rotating shaft of the secondary pulley 13b. 13f (more precisely, the center line of the rotating shaft 13d and the center line of the rotating shaft 13f) is defined as the first plane P1. ) and perpendicular to the first plane P1 (hereinafter referred to as “boundary plane”) P2, the secondary pulley 13b is arranged on the side opposite to the side on which the rotation shaft 13f of the secondary pulley 13b is arranged (Fig. 4).

By arranging the MG4 as described above, when hydraulic pressure is supplied to the CVT 13, the distance between the rotating shaft 4a of the MG4 and the rotating shaft 13d of the primary pulley 13a widens, and tension is applied to the chain 21, so the tensioner is removed. Slack of the chain 21 is suppressed even if it is not provided.

A specific configuration for suppressing the slackness of the chain 21 will be described with reference to FIGS. 2 and 3. FIG. FIG. 2 is a schematic diagram of the MG4, the chain 21, and the CVT 13. FIG. In this embodiment, the MG4 is arranged at a position sandwiching the primary pulley 13a together with the secondary pulley 13b, as shown in FIG. FIG. 3 is a schematic diagram of the isolation bearing 50 viewed from the direction of arrow C in FIG.

A rotating shaft 13 d of the primary pulley 13 a is supported by an isolation bearing 50 . The isolation bearing 50, as shown in FIG. It is inserted into the provided bearing hole. In the isolation bearing 50, when a force is applied to the rotating shaft 13d supported by the bearing main body 51 in the radial direction of the rotating shaft 13d, the low-rigidity member 52 is elastically deformed in the radial direction, and the rotating shaft 13d is displaced in the radial direction. allow.

Note that the configuration for supporting the rotating shaft 13d may be a bearing or a support member other than the isolation bearing 50 as long as it is configured to allow the displacement of the rotating shaft 13d. For example, the rotating shaft 13d may be supported by a bearing having play that allows displacement.

As shown in FIG. 2, when hydraulic pressure is supplied to the CVT 13, tension is applied to the belt 13c wound around the primary pulley 13a and the secondary pulley 13b, and the rotating shaft 13d of the primary pulley 13a approaches the secondary pulley 13b (see FIG. 2). 2 in the direction of arrow A). As a result, the distance between the rotating shaft 13d of the primary pulley 13a and the rotating shaft 4a of the MG4 widens in the direction of arrow B in FIG. Sagging is suppressed.

The hydraulic pressure of the CVT 13 required to widen the distance between the rotating shaft 13d and the rotating shaft 4a to such an extent that the slack of the chain 21 is suppressed is the minimum hydraulic pressure that enables the vehicle 100 to be driven (hereinafter referred to as the minimum hydraulic pressure). do.). Therefore, when the vehicle 100 is in a drivable state, tension is applied to the chain 21, and slackness of the chain 21 can be suppressed. Note that when the CVT 13 is not supplied with hydraulic pressure, the vehicle 100 is in a stopped state, so there is no problem even if the chain 21 is slack.

Next, with reference to FIGS. 4 and 5, the range of arrangement of the rotating shaft 4a of the MG4 where tension is applied to the chain 21 by hydraulic pressure supply to the CVT 13 will be described.

When hydraulic pressure equal to or higher than the minimum hydraulic pressure is supplied to the CVT 13, the rotating shaft 13d of the primary pulley 13a is pulled toward the secondary pulley 13b (direction of arrow A in FIGS. 4 and 5). At this time, depending on the arrangement of the rotating shaft 4a of the MG4, the distance between the rotating shaft 13d and the rotating shaft 4a may increase (FIG. 4) or decrease (FIG. 5).

As shown in FIG. 4, when the rotating shaft 4a is arranged within a range on the opposite side of the secondary pulley 13b with respect to the boundary surface P2 (above the boundary surface P2 in FIG. 4), the primary pulley When the rotating shaft 13d of 13a is pulled closer to the secondary pulley 13b, the distance between the rotating shaft 13d and the rotating shaft 4a increases in the direction of arrow B, and slackness of the chain 21 is suppressed.

On the other hand, as shown in FIG. 5, when the rotating shaft 4a is arranged on the side of the boundary surface P2 where the secondary pulley 13b is arranged (below the boundary surface P2 in FIG. 5), the primary pulley When the rotating shaft 13d of 13a is drawn toward the secondary pulley 13b (the direction of arrow A in FIG. 5), the distance between the rotating shaft 13d and the rotating shaft 4a shrinks in the direction of arrow D, and the chain 21 becomes slack. .

As described above, if the rotating shaft 4a of the MG4 is arranged within the range on the opposite side of the secondary pulley 13b with respect to the boundary surface P2, the chain can be rotated by supplying hydraulic pressure to the CVT 13 without providing a tensioner mechanism. 21 is suppressed.

Next, the effects of this embodiment will be described.

In this embodiment, the vehicle 100 includes a CVT 13 having a primary pulley 13a, a secondary pulley 13b, and a belt 13c wound around the primary pulley 13a and the secondary pulley 13b, and electric energy to generate power for driving the driving wheels 18. and a chain 21 that is stretched between the rotating shaft 4 a of the MG 4 and the rotating shaft 13 d of the primary pulley 13 a to transmit the power of the MG 4 to the CVT 13 . When a plane passing through the rotation axis 13d of the primary pulley 13a and the rotation axis 13f of the secondary pulley 13b is defined as a first plane P1, a first plane P1 passing through the rotation axis 13d of the primary pulley 13a and orthogonal to the first plane P1. 2 plane (boundary plane) P2 as a boundary, the MG4 is arranged on the side opposite to the side where the rotating shaft 13f of the secondary pulley 13b is arranged.

According to the present embodiment, when hydraulic pressure is supplied to the CVT 13, the rotation shaft 13d of the primary pulley 13a is pulled closer to the secondary pulley 13b, and a gap between the rotation shaft 13d of the primary pulley 13a and the rotation shaft 4a of the MG4 is generated. distance increases. By increasing the distance between the rotating shaft 13d and the rotating shaft 4a, tension is applied to the chain 21, and slackness of the chain 21 is suppressed without providing a tensioner mechanism. Therefore, there is no need to provide a tensioner, and the cost of providing the tensioner can be reduced, and an increase in chain friction can be suppressed (effect corresponding to claim 1).

Moreover, as a configuration that allows the displacement of the rotating shaft 13d of the primary pulley 13a, it is preferable to support the rotating shaft 13d with a bearing (for example, an isolation bearing 50) that allows the radial displacement of the rotating shaft 13d. . According to this configuration, it is possible to adjust the tension of the chain 21 when hydraulic pressure is being supplied to the CVT 13 in accordance with the amount of displacement allowed by the bearings. Effect corresponding to item 2).

Although the embodiments of the present invention have been described above, the above embodiments merely show one application example of the present invention, and the technical scope of the present invention is limited to the specific configurations of the above embodiments. not on purpose.

It is not necessary to provide the low-rigidity member 52 of the isolation bearing 50 over the entire outer periphery of the bearing main body 51 . For example, a low-rigidity member may be provided only in a direction that allows displacement of the shaft supported by the isolation bearing 50 .

Further, in this embodiment, the chain 21 is provided as a power transmission member for transmitting the power of the motor generator 4 to the continuously variable transmission mechanism 13, but a belt may be used instead of the chain 21.

4: Motor generator (motor)
4a: Rotating shaft 13: Continuously variable transmission mechanism 13a: Primary pulley 13b: Secondary pulley 13d: Rotating shaft 13f: Rotating shaft 21: Chain (power transmission member)
13: Continuously variable transmission mechanism 50: Isolation bearing (bearing)
100: hybrid vehicle

Claims (1)

a continuously variable transmission mechanism including a primary pulley, a secondary pulley, and a belt wound around the primary and secondary pulleys;
a motor that uses electric energy to generate power for driving the drive wheels;
A hybrid vehicle comprising: a power transmission member that spans the rotating shaft of the motor and the rotating shaft of the primary pulley and transmits power of the motor to the continuously variable transmission mechanism, wherein the rotating shaft of the primary pulley and the rotating shaft of the primary pulley; When a plane passing through the rotation axis of the secondary pulley is defined as a first plane, a second plane that passes through the rotation axis of the primary pulley and is perpendicular to the first plane serves as a boundary, and the motor is driven by the secondary pulley. is placed on the side opposite to the side on which the rotation axis of
further comprising a bearing that supports the rotation shaft of the primary pulley and allows radial displacement of the rotation shaft of the primary pulley;
A hybrid vehicle characterized by:

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