Fail-safe device for series hybrid vehicles

Abstract

To provide a fail-safe device for a series hybrid vehicle that can transmit driving force to the drive wheels in a low-cost configuration, even when the traction motor is unable to output sufficient driving force to drive the drive wheels. [Solution] A fail-safe device for a series hybrid vehicle comprising an engine 2, a power generation motor 3, a battery 4, and a drive motor 5 that outputs driving force for driving the drive wheels 6 using electricity generated by the power generation motor 3 and electricity charged in the battery 4, comprising a power transmission member 7 provided to transmit power to the motor output shaft 51, and a sleeve 8 mounted on the engine output shaft 21 so as to be integrally rotatable and axially movable, wherein the power transmission member 7 has a connecting portion to which the sleeve 8 is integrally rotatable, and the driving force from the engine 2 can be transmitted to the drive wheels 6 when the sleeve 8 is moved axially on the engine output shaft 21 and connected to the connecting portion.

Description

Technical Field

[0001] The present invention relates to a fail-safe device for a series hybrid vehicle.

Background Art

[0002] In Patent Document 1, in a series-parallel hybrid vehicle in which a series hybrid vehicle and a parallel hybrid vehicle are combined, when a failure of a driving motor is detected, a clutch disposed on a power transmission path between an engine and driving wheels is engaged, and when the vehicle speed becomes higher than a set value, the engine is started, and while charging a battery by a generator, driving force of the engine is transmitted to the driving wheels instead of the driving motor to make the vehicle run. A technique is disclosed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the conventional technique described in Patent Document 1, when the driving motor cannot output a driving force sufficient to drive the driving wheels, a clutch is required to transmit the driving force of the engine to the driving wheels. Furthermore, a mechanism for operating the clutch is required. For example, in the case of a hydraulic clutch, a hydraulic supply mechanism and hydraulic control are required.

[0005]

[0006] ​ The present invention has been made in view of the above circumstances, and aims to provide a fail-safe device for a series hybrid vehicle that can transmit driving force to the drive wheels in a low-cost configuration, even when the traction motor is unable to output sufficient driving force to drive the drive wheels. [Means for solving the problem]

[0007] The fail-safe device for a series hybrid vehicle according to the present invention comprises an engine, a power generator motor that generates electricity using the driving force of the engine, a battery that charges with the electricity generated by the power generator motor, and a drive motor that outputs a driving force for driving the drive wheels using the electricity generated by the power generator motor and the electricity charged in the battery, and further comprises a power transmission member provided to transmit power to the motor output shaft, which is the output shaft of the drive motor, and a sleeve attached to the engine output shaft, which is the output shaft of the engine, so as to be integrally rotatable and axially movable, wherein the power transmission member has a connecting portion to which the sleeve is integrally rotatable, and the drive force from the engine can be transmitted to the drive wheels when the sleeve is moved axially on the engine output shaft and connected to the connecting portion. [Effects of the Invention]

[0008] The present invention provides a fail-safe device for a series hybrid vehicle that can transmit driving force to the drive wheels in a low-cost configuration, even when the traction motor is unable to output sufficient driving force to drive the drive wheels. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a schematic diagram of a series hybrid vehicle equipped with a fail-safe device according to one embodiment of the present invention. [Figure 2]Figure 2 shows how a sleeve is moved using a sleeve pushing tool in a series hybrid vehicle equipped with a fail-safe device according to one embodiment of the present invention. [Figure 3] Figure 3 is a cross-sectional view of a fail-safe device according to one embodiment of the present invention. [Figure 4] Figure 4 shows the state of the fail-safe device according to one embodiment of the present invention when the engine's driving force becomes available to the first gear. [Figure 5] Figure 5 shows a modified example of a fail-safe device according to one embodiment of the present invention. [Modes for carrying out the invention]

[0010] A fail-safe device for a series hybrid vehicle according to one embodiment of the present invention is a fail-safe device for a series hybrid vehicle comprising an engine, a power generator motor that generates electricity using the driving force of the engine, a battery that is charged with the electricity generated by the power generator motor, and a drive motor that outputs driving force for driving the drive wheels using the electricity generated by the power generator motor and the electricity charged in the battery, comprising a power transmission member provided to transmit power to the motor output shaft, which is the output shaft of the drive motor, and a sleeve attached to the engine output shaft, which is the output shaft of the engine, so as to be integrally rotatable and axially movable, wherein the power transmission member has a connecting portion to which the sleeve is integrally rotatable, and the driving force from the engine can be transmitted to the drive wheels when the sleeve is moved axially on the engine output shaft and connected to the connecting portion. As a result, the fail-safe device for a series hybrid vehicle according to one embodiment of the present invention can transmit driving force to the drive wheels with a low-cost configuration even when the drive motor is unable to output sufficient driving force to drive the drive wheels. [Examples]

[0011] Hereinafter, a hybrid vehicle 1 equipped with a fail-safe device for a series hybrid vehicle according to one embodiment of the present invention will be described with reference to the drawings.

[0012] As shown in Figure 1, the hybrid vehicle 1 is composed of an engine 2, a power generation motor (indicated as MG1 in Figure 1) 3, a battery 4, a drive motor (indicated as MG2 in Figure 1) 5, drive wheels 6, a power transmission member 7, a sleeve 8, and a sleeve lock section 9.

[0013] Hybrid vehicle 1 is configured as a series hybrid vehicle in which a generator motor 3 generates electricity using the power of an engine 2, and the electricity generated by the generator motor 3 is used to drive a traction motor 5 for propulsion.

[0014] Engine 2 has multiple cylinders. In this embodiment, engine 2 generates power output via the engine output shaft 21, which is the output shaft of engine 2, by performing a series of four strokes for each cylinder, consisting of an intake stroke, a compression stroke, an expansion stroke, and an exhaust stroke.

[0015] The power generation motor 3 is installed to be linked to the engine output shaft 21. The power generation motor 3 is connected to the battery 4 via an inverter, converter, etc. (not shown). The power generation motor 3 has the function of an electric motor that starts the engine 2 by rotating when power is supplied from the battery 4, and the function of a generator that generates electricity using the driving force of the engine 2, that is, converts the power generated by the engine 2 into electricity.

[0016] Battery 4 is composed of a rechargeable secondary battery, such as a lithium-ion battery. Battery 4 charges with electricity generated by the power generation motor 3 and the driving motor 5, and supplies power to drive the power generation motor 3 and the driving motor 5.

[0017] The traveling motor 5 is provided so as to be interlocked with the drive wheels 6 via a power transmission mechanism 10 such as a gear mechanism. The traveling motor 5 is connected to the battery 4 via an inverter, a converter, etc. not shown in the figure.

[0018] The traveling motor 5 has a function of an electric motor that outputs a driving force for driving the drive wheels 6 by the electric power generated by the power generation motor 3 and the electric power charged in the battery 4, and a function of a generator that converts the rotational force of the drive wheels 6 into electric power.

[0019] The power transmission member 7 is provided so as to be able to transmit power to the motor output shaft 51 which is the output shaft of the traveling motor 5. The power transmission member 7 is composed of a first gear 71 provided rotatably, that is, relatively rotatably, on the engine output shaft 21, and a second gear 72 provided integrally rotatably on the motor output shaft 51 and constantly meshing with the first gear 71.

[0020] The first gear 71 is fixed so as not to be able to move in the axial direction with respect to the engine output shaft 21. The first gear 71 has a connecting portion 73 (see FIG. 3) to which the sleeve 8 is integrally rotatably connected.

[0021] As shown in FIG. 3, the connecting portion 73 is constituted by spline internal teeth formed along the axial direction in a hollow portion opened on the sleeve 8 side of the first gear 71.

[0022] The sleeve 8 is attached to the engine output shaft 21 so as to be integrally rotatable and axially movable. For example, spline internal teeth are formed along the axial direction on the inner peripheral surface of the sleeve 8, and spline external teeth are formed along the axial direction on the outer peripheral surface of the engine output shaft 21, and by coupling these spline teeth, the sleeve 8 can be integrally rotatable and axially movable with respect to the engine output shaft 21.

[0023] On the outer peripheral surface of the sleeve 8, spline external teeth 81 that can be fitted to the connecting portion 73 composed of spline internal teeth are formed along the axial direction.

[0024] The sleeve 8 is in an unconnected position (as shown in Figure 2) that is not connected to the coupling section 73, except during the fail-safe operation of the travel motor 5 described later. It remains in the unconnected position unless an external force acts on the sleeve 8 in the axial direction.

[0025] In contrast, when the drive motor 5 is in fail-safe mode, the sleeve 8 is pushed axially toward the first gear 71 by the sleeve pushing tool 11, moving from the unconnected position (position shown in Figure 2) to the connected position (position shown in Figure 4) where it connects to the connecting part 73. As a result, in the fail-safe mode, the sleeve 8 is connected to the connecting part 73, and the rotation of the engine output shaft 21 is transmitted to the first gear 71.

[0026] In this way, when the sleeve 8 is moved axially along the engine output shaft 21 and connected to the connecting portion 73, the driving force from the engine 2 can be transmitted to the drive wheels 6 via the power transmission member 7. As a result, the hybrid vehicle 1 can operate in fail-safe mode.

[0027] Here, "fail-safe operation of the drive motor 5" refers to a situation where, for example, the drive motor 5 fails or the battery 4 is not charged sufficiently, and the drive motor 5 is unable to output enough driving force to drive the drive wheels 6 (hereinafter, such a situation is referred to as "fail-safe operation"), and measures are taken to allow the hybrid vehicle 1 to be driven using the driving force of the engine 2.

[0028] In this embodiment, the sleeve pushing tool 11 is a device used by, for example, the driver or occupants in the event of a fail-safe, and is installed, for example, in the trunk of the hybrid vehicle 1. Thus, in this embodiment, the sleeve 8 is configured so that its axial movement relative to the engine output shaft 21 can be manually operated. Therefore, the sleeve 8 is positioned so that it can be operated by the sleeve pushing tool 11.

[0029] As shown in Figure 3, the sleeve lock portion 9 is provided on the engine output shaft 21 and has a plurality of protruding members 91 that project radially outward from the outer circumferential surface of the engine output shaft 21. The number of protruding members 91 is arbitrary and may be one.

[0030] The protruding member 91 is retracted into the engine output shaft 21 when an external force acts to push it radially inward from the radially outer side of the engine output shaft 21, and protrudes radially outward from the outer circumferential surface of the engine output shaft 21 when the external force ceases to act. A biasing member (not shown) is provided inside the engine output shaft 21 to constantly bias the protruding member 91 radially outward from the engine output shaft 21.

[0031] The protruding member 91 is a plate-shaped member arranged along the axial direction of the engine output shaft 21, and has one end face 91a on the power transmission member 7 side and another end face 91b formed on the opposite side of the axial direction from the one end face 91a.

[0032] One end face 91a faces the first gear 71, and the angle it makes with the outer surface of the engine output shaft 21 is formed at an angle (for example, 90°) that prevents the axial movement of the sleeve 8 connected to the connecting portion 73. This restricts the sleeve 8 connected to the connecting portion 73 from moving axially toward the engine 2.

[0033] The other end face 91b is formed such that the angle it makes with the outer surface of the engine output shaft 21 gradually increases as the amount of protrusion from the engine output shaft 21 moves toward the first gear 71, allowing the sleeve 8 to move axially. This allows the sleeve 8 to move axially when it is pushed axially toward the first gear 71 by the sleeve pushing tool 11 during failsafe operation.

[0034] Thus, the sleeve lock portion 9 allows movement of the sleeve 8 when it is pushed axially toward the first gear 71 by the sleeve pushing tool 11, while preventing axial movement of the sleeve 8 after it is connected to the connecting portion 73.

[0035] As described above, in the fail-safe device of the series hybrid vehicle according to this embodiment, the sleeve 8, which is attached to the engine output shaft 21 so as to be integrally rotatable and axially movable, is moved axially along the engine output shaft 21 and connected to the connecting portion 73 of the power transmission member 7 which can transmit power to the motor output shaft 51. This allows the driving force from the engine 2 to be transmitted to the drive wheels 6, so that even in the event of a failure when the traction motor is unable to output sufficient driving force to drive the drive wheels, driving force can be transmitted to the drive wheels 6.

[0036] Furthermore, in the fail-safe device of the series hybrid vehicle according to this embodiment, the driving force from the engine 2 can be transmitted to the drive wheels 6 by connecting the sleeve 8 and the connecting portion 73 of the power transmission member 7, so a clutch or a mechanism to operate the clutch is unnecessary, and an increase in cost can be avoided.

[0037] The fail-safe device of the series hybrid vehicle according to this embodiment is composed of a first gear 71 rotatably mounted on the engine output shaft 21 and a second gear 72 that is integrally rotatably mounted on the motor output shaft 51 and constantly meshes with the first gear 71. Therefore, during fail-safe driving, the driving force of the engine 2 can be reliably transmitted to the motor output shaft 51 with a low-cost configuration.

[0038] The fail-safe device of the series hybrid vehicle according to this embodiment further includes a sleeve lock 9 that prevents the axial movement of the sleeve 8 after the sleeve 8 is connected to the coupling portion 73. This prevents the sleeve 8 from disengaging from the first gear 71 during fail-safe driving, which would prevent the driving force from the engine 2 from being transmitted to the drive wheels 6.

[0039] In the fail-safe device for a series hybrid vehicle according to this embodiment, the sleeve lock portion 9 has a protruding member 91 that protrudes radially outward from the outer circumferential surface of the engine output shaft 21. The protruding member 91 is configured to be retracted into the engine output shaft 21 when an external force acts to push it radially inward from the radially outward side, and to protrude radially outward from the outer circumferential surface of the engine output shaft 21 when the external force ceases to act.

[0040] Therefore, when the sleeve 8 is positioned on the engine 2 side of the protruding member 91 and no external force is generated that causes it to slide from the engine 2 side towards the first gear 71, it is possible to prevent the sleeve 8 from sliding from the engine 2 side towards the first gear 71. On the other hand, when the sleeve 8 is positioned on the engine 2 side of the protruding member 91 and an external force is generated that causes it to slide from the engine 2 side towards the first gear 71, it becomes possible to slide the sleeve 8 from the engine 2 side towards the first gear 71.

[0041] Furthermore, when the sleeve 8 is positioned on the first gear 71 side of the protruding member 91 and no external force is generated that causes it to slide from the first gear 71 side towards the engine 2 side, it is possible to prevent the sleeve 8 from sliding from the first gear 71 side towards the engine 2 side. On the other hand, when the sleeve 8 is positioned on the first gear 71 side of the protruding member 91 and an external force is generated that causes it to slide from the engine 2 side towards the first gear 71 side, it becomes possible to slide the sleeve 8 from the first gear 71 side towards the engine 2 side.

[0042] In the fail-safe device for a series hybrid vehicle according to this embodiment, the protruding member 91 has one end face 91a on the power transmission member 7 side and another end face 91b formed on the opposite side in the axial direction from the one end face 91a. The one end face 91a is formed at an angle that it makes with the outer circumferential surface of the engine output shaft 21, which prevents the axial movement of the sleeve 8 connected to the connecting portion 73. The other end face 91b is formed at an angle that it makes with the outer circumferential surface of the engine output shaft 21, which allows the axial movement of the sleeve 8, such that the amount of protrusion from the engine output shaft 21 gradually increases towards the first gear 71 side.

[0043] Therefore, it is possible to reliably prevent the sleeve 8 from detaching from the connecting portion 73 of the first gear 71 during fail-safe operation, which would prevent the driving force from the engine 2 from being transmitted to the drive wheels 6.

[0044] In the fail-safe device for a series hybrid vehicle according to this embodiment, since the protruding member 91 is made of a plate-shaped member arranged along the axial direction, the storage space formed on the engine output shaft 21 can be reduced, and the rigidity of the engine output shaft 21 can be avoided.

[0045] In the fail-safe device for a series hybrid vehicle according to this embodiment, the sleeve 8 is configured to be manually movable in the axial direction, so a drive source for moving the sleeve 8 is not required, and the sleeve 8 can be moved easily and reliably.

[0046] In this embodiment, an example of manually operating the sleeve 8 has been described, but it is not limited to this. For example, an operating member such as a lever provided inside the vehicle interior may be connected to the sleeve 8 by a link member such as a wire, and the sleeve 8 may be moved in the axial direction by operating the operating member from inside the vehicle interior.

[0047] Furthermore, although this embodiment describes an example in which the protruding member 91 is a plate-shaped member, the embodiment is not limited to this, and the protruding member 91 may also be a block-shaped member.

[0048] Furthermore, although this embodiment describes an example in which the fail-safe device for a series hybrid vehicle according to the present invention is applied to a hybrid vehicle 1, it is not limited to this, and may also be applied to a hybrid vehicle 101 with a configuration such as that shown in Figure 5.

[0049] As shown in Figure 5, the hybrid vehicle 101 has an engine output shaft 21 and a motor output shaft 51 that rotate independently of each other and are arranged coaxially. A motor output gear 52 is fixed to the motor output shaft 51 of the driving motor 5 so as to be able to rotate together with it.

[0050] A transmission gear 53 meshes with the motor output gear 52, and a transmission gear 54 is connected to the transmission gear 53 so as to rotate together with it. The transmission gear 54 meshes with the power transmission mechanism 10. As a result, the driving force of the traction motor 5 is transmitted to the drive wheels 6 via the motor output gear 52, transmission gears 53 and 54, and the power transmission mechanism 10.

[0051] In the hybrid vehicle 101 configured in this way, the power transmission member 7 consists of a motor output gear 52 that is integrally rotatable with the motor output shaft 51.

[0052] The motor output gear 52 is provided with a connecting portion 73. Therefore, in the event of a fail-safe operation of the drive motor 5, when the sleeve 8 is pushed axially toward the motor output gear 52 by the sleeve pushing tool 11, the sleeve 8 is connected to the connecting portion 73, and the rotation of the engine output shaft 21 is transmitted to the motor output gear 52.

[0053] When the sleeve 8 is moved axially along the engine output shaft 21 and connected to the connecting portion 73, the driving force from the engine 2 can be transmitted to the drive wheels 6 via the power transmission member 7 consisting of the motor output gear 52.

[0054] Although embodiments of the present invention have been disclosed above, it is clear that modifications can be made to these embodiments without departing from the scope of the present invention. The embodiments of the present invention are disclosed on the premise that equivalents with such modifications are included in the invention described in the claims. [Explanation of Symbols]

[0055] 1. 101 Hybrid Vehicles (Series Hybrid Vehicles) 2 engines 3. Generating motor 4 Batteries 5. Motor for driving 6 drive wheels 7 Power transmission member 8 sleeves 9 Sleeve Lock Section 10 Power transmission mechanism 11. Sleeve push-in tool 21 Engine output shaft 51 Motor output shaft 52 Motor output gear 71 First gear 72 Second gear 73 Connecting part 91 Protruding member 91a One end face 91b Other end surface

Claims

1. The engine and A power generation motor that generates electricity using the driving force of the aforementioned engine, A battery that is charged with electricity generated by the aforementioned power generation motor, A fail-safe device for a series hybrid vehicle comprising: a drive motor that outputs driving force for driving the drive wheels using electricity generated by the aforementioned power generation motor and electricity charged in the battery, A power transmission member is provided to transmit power to the motor output shaft, which is the output shaft of the aforementioned drive motor, The engine output shaft, which is the output shaft of the engine, is equipped with a sleeve that is integrally rotatable and axially movable, The power transmission member has a connecting portion to which the sleeve is integrally rotatably connected, A fail-safe device for a series hybrid vehicle, characterized in that the sleeve is moved axially along the engine output shaft and connected to the connecting portion, thereby enabling the driving force from the engine to be transmitted to the drive wheels.

2. The power transmission member is A first gear is rotatably mounted on the engine output shaft, The fail-safe device for a series hybrid vehicle according to claim 1, characterized in that it comprises a second gear that is rotatably mounted integrally with the motor output shaft and constantly meshes with the first gear.

3. The engine output shaft and the motor output shaft are arranged coaxially. The fail-safe device for a series hybrid vehicle according to claim 1, characterized in that the power transmission member consists of a motor output gear that is integrally rotatable with the motor output shaft.

4. The fail-safe device for a series hybrid vehicle according to any one of claims 1 to 3, further comprising a sleeve lock portion that prevents the sleeve from moving in the axial direction after the sleeve is connected to the connecting portion.

5. The sleeve lock portion is provided on the engine output shaft and has a protruding member that protrudes radially outward from the outer circumferential surface of the engine output shaft. The fail-safe device for a series hybrid vehicle according to claim 4, characterized in that the protruding member is retracted into the engine output shaft when an external force acts to push it radially inward from the radially outward side of the engine output shaft, and protrudes radially outward from the outer circumferential surface of the engine output shaft when the external force ceases to act.

6. The protruding member has one end face on the power transmission member side and another end face formed on the opposite side in the axial direction from the one end face. The angle that the aforementioned end face makes with the outer circumferential surface of the engine output shaft is such that it prevents the sleeve connected to the connecting portion from moving in the axial direction. The fail-safe device for a series hybrid vehicle according to claim 5, characterized in that the other end face is formed such that the angle it makes with the outer circumferential surface of the engine output shaft is such that the amount of protrusion from the engine output shaft gradually increases towards the power transmission member side, allowing the sleeve to move in the axial direction.

7. The fail-safe device for a series hybrid vehicle according to claim 6, characterized in that the protruding member consists of a plate-shaped member arranged along the axial direction.

8. The fail-safe device for a series hybrid vehicle according to any one of claims 1 to 3, characterized in that the sleeve is configured to be manually operable for movement in the axial direction.

Images