JP2014037884A - Driving power transmission device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a driving power transmission device capable of: improving the responsibility of driving force distribution to first and second driving wheels using a distributing drive source; and reducing the size of and a manufacturing cost for the device.SOLUTION: In a driving power transmission device, revolution speeds of first to third rotary elements GL, DC and GR are mutually in common line connections and the elements are individually connected to a first driving wheel WL, a vehicular drive source 3 and a second driving wheel WR; the revolution speeds of fourth to sixth rotary elements S, C and R are mutually in common line connections; the fourth rotary element S is connected to a distributing drive source 11; a first gear G1 made rotatable integrally with the first rotary element GL meshes with a third gear G3 made rotatable integrally with the fifth rotary element C; and a second gear G2 made rotatable integrally with the second rotary element DC meshes with a fourth gear G4 made rotatable integrally with the sixth rotary element R.

Description

  The present invention relates to a driving force transmission device that transmits driving force from a vehicle driving source to first and second driving wheels for propelling a vehicle.

  Conventionally, as this type of driving force transmission device, for example, a device disclosed in Patent Document 1 is known. As shown in FIG. 17, the driving force transmission device includes a differential device ds, a planetary gear device ps, and a rotating electrical machine M. The differential device ds is of a bevel gear type, and supports left and right side gears gl and gr, a plurality of pinion gears pi (only two shown) meshing with both side gears gl and gr, and rotatably supports these pinion gears pi. It has a differential case dc. The differential case dc is connected to an engine E that is a drive source of the vehicle. The differential case dc is integrally provided with a gear 101. Further, the left side gear gl is integrally attached to the left output shaft sl connected to the left drive wheel wl, and the right side gear gr is attached integrally to the right output shaft sr connected to the right drive wheel wr. It has been.

  The planetary gear unit ps is of a single pinion type, and includes a sun gear s, a ring gear r, a plurality of planetary gears pl (only two shown) meshing with both gears s, r, and these planetary gears pl are rotatable. And a carrier c to be supported. The sun gear s is integrally provided with a gear 102, and the gear 102 meshes with a gear 103 provided integrally with the output shaft of the rotating electrical machine M. The carrier c is integrally attached to the left output shaft sl. A gear 104 is integrally provided on the outer periphery of the ring gear r.

  Further, the drive force transmission device is provided with an idler shaft is, and a first gear 105 and a second gear 106 are integrally attached to both ends of the idler shaft is. The first gear 105 meshes with the gear 104 integrated with the ring gear r described above, and the second gear 106 meshes with the gear 101 integrated with the differential case dc described above. The number of teeth of the sun gear s, the ring gear r, the gear 104, and the gear 101 is set as follows. That is, when the vehicle is traveling straight, when the rotational speeds of the left and right drive wheels wl and wr are equal to each other and the rotational speeds of the left and right side gears gl and gr and the differential case dc are equal to each other, The number of teeth of each of the gears s, r, 104, and 101 is set so as to be held in a stopped state.

  In the conventional driving force transmission device configured as described above, the driving force of the engine E is transmitted to the differential case dc of the differential device ds, and further, left and right via the left and right side gears gl and gr and the left and right output shafts sl and sr. Are distributed to the driving wheels wl and wr. Further, during the left and right turn of the vehicle, the driving force distributed to the left and right driving wheels wl and wr is changed by controlling the driving force of the rotating electrical machine M (hereinafter referred to as “motor driving force”). Hereinafter, this point will be described.

  FIG. 18 shows the transmission state of the driving force between the various rotating elements when the motor driving force of the rotating electrical machine M is generated when the vehicle turns right. As shown by the thick line with the hatched arrow in the figure, the motor driving force is transmitted to the sun gear s via the gear 103 and the gear 102 and is combined with the driving force transmitted to the ring gear r as will be described later. Then, it is transmitted to the carrier c through the planetary gear pl, and further transmitted to the left drive wheel wl through the left output shaft sl. Accordingly, part of the driving force transmitted to the differential case dc is transmitted to the ring gear r through the gear 101, the second gear 106, the idler shaft is, the first gear 105, and the gear 104. As described above, during the right turn of the vehicle, the driving force distributed to the left driving wheel wl becomes larger than that of the right driving wheel wr.

  FIG. 19 shows a transmission state of the driving force between the various rotating elements when the motor driving force of the rotating electrical machine M is generated when the vehicle turns left. As shown by the hatched thick line with an arrow in the figure, the motor driving force is transmitted to the sun gear s via the gear 103 and the gear 102 and is combined with the driving force transmitted to the carrier c as will be described later. And transmitted to the ring gear r via the planetary gear pl. The driving force transmitted to the ring gear r is transmitted to the differential case dc via the gear 104, the first gear 105, the idler shaft is, the second gear 106, and the gear 101, and further includes a pinion gear pi, left and right side gears gl, It is transmitted to the left and right drive wheels wl and wr via gr and the left and right output shafts sl and sr. Accordingly, a part of the driving force transmitted to the left output shaft sl is transmitted to the carrier c. As described above, during the left turn of the vehicle, the driving force distributed to the right driving wheel wr becomes larger than that of the left driving wheel wl.

Japanese Patent Application Laid-Open No. 07-019318

  As shown in FIG. 18 described above, in the conventional driving force transmission device, with the generation of the motor driving force, the left driving wheel wl is transmitted to the carrier c via the gear 103, the gear 102, the sun gear s and the planetary gear pl. A driving force obtained by combining the driving force transmitted and the driving force transmitted to the carrier c via the ring gear r and the planetary gear pl is transmitted via the left output shaft sl. In this case, the number of gear meshes directly related to transmission of the driving force to the left drive wheel wl is “mesh between the gear 103 and the gear 102” and “mesh between the sun gear s and the planetary gear pl. "And" meshing between planetary gear pl and ring gear r ", a total of three.

  As the motor drive force is generated, the left and right drive wheels wl and wr include the gear 103, the gear 102, the sun gear s, the planetary gear pl, the ring gear r, the gear 104, the first gear 105, the idler shaft is, and the second gear. 106, a negative driving force is transmitted through the gear 101, the differential case dc, the pinion gear pi, the left and right side gears gl and gr, and the left and right output shafts sl and sr, respectively. In this case, the number of gear meshes directly related to the transmission of the driving force to the right drive wheel wr is “mesh between the gear 103 and the gear 102” and “mesh between the sun gear s and the planetary gear pl. "," Meshing between planetary gear pl and ring gear r "," meshing between gear 104 and first gear 105 "," meshing between second gear 106 and gear 101 "and" pinion gear pi and left There are a total of seven "meshing between the side gears gl" and "meshing between the pinion gear pi and the right side gear gr".

  As described above, in the conventional driving force transmission device, the carrier c of the planetary gear device ps is directly connected to the left driving wheel wl, whereas the ring gear r is the gear 104 and the first gear 105 of the idler shaft is. The left and right drive wheels wl and wr are connected to each other through the second gear 106 and the gear 101. For this reason, the number of meshes of the gears 104, 105, 106 and 101, which are directly related to the transmission of the driving force, greatly differs between the left and right drive wheels wl, wr, The difference (| 3-7 | = 4) becomes large. As apparent from the comparison between FIG. 18 and FIG. 19, this applies not only when the vehicle turns right as shown in FIG. 18, but also when the vehicle turns left as shown in FIG. Further, the configuration as described above is indispensable for maintaining the rotational speeds of the sun gear s and the rotating electrical machine M at the value 0 when the vehicle is traveling straight in the conventional driving force transmission device.

  In the conventional driving force transmission device, the influence of the gear backlash differs greatly between the left and right drive wheels wl and wr due to the difference in the number of meshing gears described above. The responsiveness of driving force distribution to the driving wheels wl and wr of the left and right driving wheels wl and wr is greatly different between the right and left driving wheels wl and wr, and this driving force distribution may not be performed properly. Further, since the idler shaft is is provided, the driving force transmission device is increased in size and the manufacturing cost is increased.

  The present invention has been made to solve the above-described problems, and can improve the responsiveness of the driving force distribution to the first and second drive wheels using the distribution drive source, It is an object of the present invention to provide a driving force transmission device that can reduce the size of the device and reduce the manufacturing cost.

  In order to achieve the above object, the invention according to claim 1 is the first and second drive wheels for propelling the vehicle (left and right drive wheels WL, WR in the embodiment (hereinafter the same in this section)). And a first driving element (left side gear GL) that transmits a driving force from a vehicle driving source (the engine 3, the rotating electric machine 41, and the rotating electric machine 51) and that can transmit power between them. ), A second rotation element (difference case DC) and a third rotation element (right side gear GR), and the rotation speeds of the first to third rotation elements are arranged in this order on a single straight line in the alignment chart. The first differential device (differential device DS) configured to satisfy the line relationship, the first gears G1 and G1 ′ that are integrally rotatable with the first rotation element, and the second rotation element And second gears G2 and G2 ′ provided rotatably, The rotation element is connected to the first drive wheel (left drive wheel WL), the second rotation element is connected to the vehicle drive source, and the third rotation element is connected to the second drive wheel (right drive wheel WR). And includes a fourth rotating element (sun gear S), a fifth rotating element (carrier C), and a sixth rotating element (ring gear R) that can transmit power between each other. Driving force is output to the second differential element (planetary gear unit PS) configured to satisfy the collinear relationship in which rotation speeds are arranged in this order on a single straight line in the collinear diagram and the fourth rotation element A distribution drive source (rotating electrical machine 11) that is connected to the third rotation element and a third rotation element that is integrally rotatable with the fifth rotation element and meshes with one of the first and second gears G1, G1 ′, G2, and G2 ′. Gears G3 and G3 ′, and a sixth gear and a sixth gear, are provided so as to be integrally rotatable. 1, G1 ', G2, G2' between the other and the meshing fourth gear G4, G4 ', and further comprising a.

  According to this configuration, the first to third rotating elements of the first differential device can transmit power to each other, and the rotational speeds of the first to third rotating elements are simply shown in the collinear diagram. They are in a collinear relationship on a straight line in this order. The first rotation element is connected to the first drive wheel of the vehicle, the second rotation element is connected to the vehicle drive source, and the third rotation element is connected to the second drive wheel of the vehicle. Therefore, the driving force from the vehicle drive source can be transmitted to the first and second drive wheels via the first differential.

  Moreover, the 1st and 2nd gear is each provided in the 1st and 2nd rotation element so that rotation is possible integrally. Further, the second differential device is configured so that the rotational speeds of the fourth to sixth rotating elements satisfy a collinear relationship arranged in this order on a single straight line in the collinear diagram. In addition, a distribution drive source is connected to the fourth rotation element, and a third gear is provided to the fifth rotation element, and a fourth gear is provided to the sixth rotation element so as to be integrally rotatable. . Furthermore, the third gear meshes with one of the first and second gears (hereinafter referred to as “one gear”), and the fourth gear engages with the other of the first and second gears (hereinafter referred to as “the other gear”). I'm engaged. The second differential device, the distribution drive source, and the first to fourth gears constitute a drive force distribution device that can change the drive force distributed to the first and second drive wheels. Hereinafter, this point will be described.

  From the connection relationship between the various rotating elements in the driving force transmission device described above, the relationship between the rotational speeds of these various rotating elements is that the third gear is the first gear and the fourth gear is the second gear. When the gears are engaged with each other, for example, the collinear chart shown in FIG. 20 is shown. On the contrary, when the third gear is engaged with the second gear and the fourth gear is engaged with the first gear, respectively. For example, it is represented as a collinear chart shown in FIG.

  As is apparent from FIGS. 20 and 21, when the driving force of the distribution drive source (hereinafter referred to as “distribution drive force”) is input to the fourth rotating element, the drive force from the first differential device. Is input to one of the fifth and sixth rotating elements, and combined with the driving force input to the fourth rotating element, the first or second driving is performed via the other of the fifth and sixth rotating elements. Transmitted to the wheel. Thereby, the driving force distributed to the first and second driving wheels is changed. In this case, the number of meshing gears between the fifth rotating element and the first differential gear is “1 meshing between the third gear and one gear”, which is one. The number of meshing gears between the differentials is also “one meshing between the fourth gear and the other gear”. Thus, unlike the conventional case described above, the number of gear meshes directly related to the transmission of the driving force (including negative driving force) to the first driving wheel and the driving force to the second driving wheel. The difference from the number of meshing gears directly related to transmission (including negative driving force) can be reduced. Therefore, it is possible to improve the response of the driving force distribution to the first and second drive wheels using the distribution drive source.

  Further, since the above-described conventional idler shaft is is unnecessary, the apparatus can be reduced in size and the manufacturing cost can be reduced accordingly.

  Furthermore, when the first and second drive wheels are driven by transmission of driving force from the vehicle drive source via the first differential, the various rotating elements are connected as described above, so that the vehicle In some cases, the driving force of the distribution drive source is unnecessarily transmitted to the distribution drive source and drags the distribution drive source. According to the present invention, as shown in FIGS. 20 and 21, when the rotation speeds of the first and second drive wheels are equal to each other, the driving force is transmitted so that the distribution drive source is held in a stopped state. Since the device can be configured, the above-described distribution drive source can be prevented from being dragged, thereby improving the controllability of the vehicle.

  As shown in FIGS. 20 and 21, the second rotating element is used as an object to which one of the fifth and sixth rotating elements (hereinafter referred to as “one rotating element”) is connected. Unlike the present invention, when the third rotating element connected to the second driving wheel is used as an object to which the one rotating element is connected, the first and second driving using the distribution driving source described above. During the distribution of the driving force to the wheels, torque is exchanged with one rotating element directly to the second driving wheel, so that the torque difference between the first and second driving wheels is reduced. It becomes relatively large.

  According to the present invention, since the second rotating element is used as an object to which one rotating element is connected, the one rotating element is distributed during the distribution of the driving force to the first and second driving wheels using the distributing drive source. The torque can be exchanged between the first and second drive wheels. As a result, the torque difference between the first and second drive wheels can be reduced with respect to the output torque of the distribution drive source having the same size, so that the drive force is more distributed to the first and second drive wheels. Can be done finely.

  20 and 21, the first to third rotating elements are directly connected to the first driving wheel, the vehicle driving source, and the second driving wheel, respectively, and the fourth rotating element is directly connected to the distribution driving source. However, these rotating elements do not necessarily have to be directly connected to each other as long as they are connected.

  According to a second aspect of the present invention, in the driving force transmission device according to the first aspect, the fourth rotating element is held in a stopped state when the rotation speeds of the first and second drive wheels are equal to each other. The first to fourth gears G1, G1 ′, G2, G2 ′, G3, G3 ′, G4, G4 ′ and the second differential device are configured.

  According to this configuration, the first to fourth gears and the second differential device are configured so that the fourth rotation element is held in the stopped state when the rotation speeds of the first and second drive wheels are equal to each other. ing. Thus, as described with reference to FIGS. 20 and 21 described above, when the first and second drive wheels are being driven by the vehicle drive source and the rotation speeds of both drive wheels are equal to each other, It is possible to reliably prevent the distribution drive source connected to the rotating element from being dragged.

  According to a third aspect of the present invention, in the driving force transmission device according to the first or second aspect, the second differential device includes a sun gear S as a fourth rotating element, and a sixth rotation provided on the outer periphery of the sun gear S. It comprises a single pinion type planetary gear unit PS having a ring gear R as an element and a carrier C as a fifth rotating element that rotatably supports a sun gear S and a planetary gear PL meshing with the ring gear R. Is ZS, the number of teeth of the ring gear R is ZR, the number of teeth of one of the first and second gears G1, G1 ′, G2, and G2 ′ is ZGA, and the first and second gears G1, G1 ′, G2, When the other number of teeth of G2 ′ is ZGB, the number of teeth of the third gear G3, G3 ′ is ZG3, and the number of teeth of the fourth gears G4, G4 ′ is ZG4, ZG3 / ZGA = (1 + ZS / ZR) ) X (Z 4 / ZGB), the number of teeth ZS of the sun gear, the number of teeth ZR of the ring gear, the number of teeth ZGA of the first and second gears, the number of teeth ZGB of the other of the first and second gears, the third The number of gear teeth ZG3 and the number of teeth ZG4 of the fourth gear are set.

  According to this structure, the 2nd differential gear is comprised with the single pinion type planetary gear apparatus, and the 4th-6th rotation elements are a sun gear, a carrier, and a ring gear, respectively. The number of teeth of the sun gear is ZS, the number of teeth of the ring gear is ZR, the number of teeth of one of the first and second gears is ZGA, the number of teeth of the third gear is ZG3, and the number of teeth of the first and second gears is When the number of teeth of the other gear is ZGB and the number of teeth of the fourth gear is ZG4, the number of teeth ZS of these gears so that ZG3 / ZGA = (1 + ZS / ZR) × (ZG4 / ZGB) is satisfied. ZR, ZGA, ZG3, ZGB and ZG4 are set.

As described above, the third gear meshes with one gear (one of the first and second gears), and the fourth gear meshes with the other gear (the other of the first and second gears). Therefore, if the rotation speed of the third gear is NG3, the rotation speed of one gear is NGA, the rotation speed of the fourth gear is NG4, and the rotation speed of the other gear is NGB, The following expressions (1) and (2) are established.
NG3 × ZG3 = NGA × ZGA (1)
NG4 × ZG4 = NGB × ZGB (2)

Further, the first to third rotating elements have their rotational speeds collinear with each other, the first and second rotating elements are connected to the first and second drive wheels, respectively, Since the first and second gears are rotatably provided integrally with the second rotation element, respectively, when the rotation speeds of the first and second drive wheels are equal to each other, the rotation speed NGA of one gear is NGA = NGB is established between the rotational speed NGB of the other gear. From this and the above equations (1) and (2), the following equation (3) is established.
NG3 (ZG3 / ZGA) = NG4 (ZG4 / ZGB) (3)

Further, since the second differential device is a single pinion type planetary gear device, assuming that the rotation speed of the carrier is NC, the rotation speed of the ring gear is NR, and the rotation speed of the sun gear is 0, both NC and The following equation (4) is established between NRs.
NR = (1 + ZS / ZR) NC (4)

Further, since the third gear is provided so as to be rotatable integrally with the fifth rotation element, that is, the carrier, the rotation speed NG3 of the third gear and the rotation speed NC of the carrier are equal to each other (NG3 = NC). Further, since the fourth gear is provided so as to be integrally rotatable with the sixth rotation element, that is, the ring gear, the rotation speed NG4 of the fourth gear and the rotation speed NR of the ring gear are equal to each other (NG4 = NR). From these and the above equations (3) and (4), the following equation (5) is established. This equation (5) is the same as the equation for setting each gear in the present invention described above.
ZG3 / ZGA = (1 + ZS / ZR) × (ZG4 / ZGB) (5)

  As described above, according to the present invention, when the rotation speeds of the first and second drive wheels are equal to each other, the rotation speed of the sun gear is set to 0, that is, the sun gear and the distribution drive source connected thereto are stopped. Since it can hold | maintain, the effect that the drag of the distribution drive source can be prevented reliably can be acquired effectively.

  According to a fourth aspect of the present invention, in the driving force transmission device according to any one of the first to third aspects, the distribution drive source is the rotating electrical machine 11.

  As described with reference to FIGS. 20 and 21, the driving force transmission device is configured so that the distribution drive source is held in a stopped state when the rotation speeds of the first and second drive wheels are equal to each other. can do. Thereby, when a differential rotation occurs between the first and second drive wheels, the number of rotations of the distribution drive source can be kept relatively low. According to the present invention, since the distribution drive source is a rotating electrical machine, it has a characteristic of generating a larger output torque when its rotational speed is relatively low. As described above, when the differential rotation between the first and second drive wheels occurs, the torque of the distribution drive source can be sufficiently generated, thereby appropriately distributing the drive force to both drive wheels. Can do.

1 is a skeleton diagram showing a driving force transmission device and the like according to a first embodiment of the present invention. It is a block diagram which shows ECU etc. of the driving force transmission apparatus of FIG. FIG. 3 is a collinear diagram illustrating a rotational speed relationship and a torque balance relationship between various types of rotary elements in the driving force transmission apparatus of FIG. 1 when the vehicle is traveling straight. FIG. 2 is a collinear diagram showing a rotational speed relationship and a torque balance relationship between various types of rotary elements in the driving force transmission apparatus of FIG. 1 when the vehicle is turning left. It is a figure which shows the transmission condition of the driving force in the driving force transmission apparatus of FIG. 1 at the time of the left turn of a vehicle. FIG. 2 is a collinear diagram showing a rotational speed relationship and a torque balance relationship between various types of rotary elements in the driving force transmission apparatus of FIG. 1 when the vehicle turns right. It is a figure which shows the transmission condition of the driving force in the driving force transmission apparatus of FIG. 1 at the time of the vehicle turning right. It is a skeleton figure which shows the 1st modification of the driving force transmission apparatus by 1st Embodiment. It is a skeleton figure which shows the 2nd modification of the driving force transmission apparatus by 1st Embodiment. It is a skeleton figure which shows the 3rd modification of the driving force transmission apparatus by 1st Embodiment. It is a skeleton diagram showing a driving force transmission device and the like according to a second embodiment of the present invention. FIG. 12 is a collinear diagram illustrating a rotational speed relationship and a torque balance relationship between various types of rotary elements in the driving force transmission device of FIG. 11 when the vehicle is traveling straight. FIG. 12 is a collinear diagram illustrating a rotational speed relationship and a torque balance relationship between various types of rotary elements in the driving force transmission device of FIG. 11 when the vehicle is turning left. It is a figure which shows the transmission condition of the driving force in the driving force transmission apparatus of FIG. 11 at the time of the left turn of a vehicle. FIG. 12 is a collinear diagram showing a rotational speed relationship and a torque balance relationship between various types of rotary elements in the driving force transmission apparatus of FIG. 11 when the vehicle turns right. It is a figure which shows the transmission condition of the driving force in the driving force transmission apparatus of FIG. 11 at the time of the vehicle turning right. It is a skeleton diagram showing a conventional driving force transmission device and the like. It is a figure which shows the transmission condition of the driving force in the conventional driving force transmission apparatus at the time of the vehicle turning right. It is a figure which shows the transmission condition of the driving force in the conventional driving force transmission apparatus at the time of the left turn of a vehicle. FIG. 6 is a collinear diagram showing the relationship of the rotational speeds between various rotary elements in the driving force transmission device of the present invention when the third gear is engaged with the first gear and the fourth gear is engaged with the second gear. is there. FIG. 5 is a collinear diagram showing the relationship of the rotational speeds between various rotary elements in the driving force transmission device of the present invention when the third gear is engaged with the second gear and the fourth gear is engaged with the first gear. is there.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. As shown in FIG. 1, the driving force transmission device according to the first embodiment is for transmitting a driving force from an internal combustion engine (hereinafter referred to as “engine”) 3 to left and right driving wheels WL, WR of the vehicle. The engine 3 is connected to the left and right drive wheels WL and WR. The engine 3 is a gasoline engine, and a transmission 4 is connected to a crankshaft (not shown). The transmission 4 outputs the driving force of the engine 3 (hereinafter referred to as “engine driving force”) from the output shaft 4a in a shifted state. The output shaft 4a is integrally provided with a gear 4b that is a spur gear or a helical gear.

  The driving force transmission device includes a differential device DS, a planetary gear device PS, and a rotating electrical machine 11. The differential device DS is for transmitting the engine driving force changed by the transmission 4 to the left and right drive wheels WL, WR. The differential device DS is of a bevel gear type, a pair of left side gear GL and right side gear GR, a plurality of pinion gears PI (only two shown) meshing with both side gears GL and GR, and these pinion gears PI are freely rotatable. A differential case DC is supported. As is well known, the left side gear GL, the differential case DC, and the right side gear GR can transmit power to each other, and their rotational speeds are arranged in this order on a single straight line in the alignment chart. There is a relationship. The number of teeth of the left and right side gears GL and GR is set to the same value.

  The left side gear GL and the right side gear GR are integrally provided on the left output shaft SL and the right output shaft SR, respectively. These left and right output shafts SL and SR are rotatably supported by bearings (not shown) and are connected to left and right drive wheels WL and WR, respectively. Further, the left output shaft SL is integrally provided with a first gear G1, and the first gear G1 and the left side gear GL are rotatable together.

  The differential case DC is rotatably supported by a bearing (not shown). A second gear G2 and a gear 5 are integrally attached to the differential case DC via a flange or a hollow rotating shaft, and the differential case DC, the second gear G2, and the gear 5 are integrally rotatable with each other. The gear 5 is a ring-shaped spur gear or a helical gear, and meshes with the gear 4b of the transmission 4 described above. As described above, the differential case DC is connected to the engine 3. The engine driving force is transmitted to the differential case DC via the transmission 4, the gear 4a and the gear 5, is transmitted to the left and right side gears GL and GR via the pinion gear PI, and further left and right via the left and right output shafts SL and SR. Are transmitted to the driving wheels WL and WR. In this case, the torque distribution ratio to the left and right drive wheels WL and WR is 1: 1.

  The planetary gear device PS functions as a driving force distribution device that changes the distribution ratio of the driving force distributed to the left and right driving wheels WL and WR together with the rotating electrical machine 11. Specifically, the planetary gear device PS is of a single pinion type, and includes a sun gear S, a ring gear R provided on the outer periphery of the sun gear S, and a plurality of planetary gears PL (only two) meshing with the two gears S, R. And a carrier C that rotatably supports these planetary gears PL. As is well known, these sun gear S, carrier C and ring gear R can transmit power between each other, and their rotational speeds are arranged in a collinear relationship in this order on a single straight line in the collinear diagram. is there.

  The sun gear S is provided integrally with a rotating shaft 11a, which will be described later, of the rotating electrical machine 11, and is rotatable integrally with the rotating shaft 11a. The carrier C includes a base portion Ca having a donut plate shape and a support shaft Cb that is integrally provided at the radial center of the base portion Ca and extends in the axial direction. The planetary gear PL is rotatably supported on the support shaft Cb via a bearing (not shown). In addition, the rotating shaft 11a of the rotating electrical machine 11 is fitted into the hole at the center of the base Ca through a bearing (not shown). Thereby, the carrier C is relatively rotatable with the rotating shaft 11a and the sun gear S integrated therewith. Further, a third gear G3 is integrally provided on the outer peripheral portion of the base Ca, and the third gear G3 and the carrier C are rotatable integrally with each other. Further, the third gear G3 meshes with the first gear G1 described above.

  A fourth gear G4 is attached to the outer peripheral portion of the ring gear R via a flange or a hollow rotating shaft, and both R and G4 are rotatable together. Further, the fourth gear G4 meshes with the second gear G2 described above.

  The rotating electrical machine 11 is an AC motor, and includes a stator composed of a plurality of iron cores and coils, and a rotor composed of a plurality of magnets (all not shown). The rotor is integrally provided with a rotation shaft 11a. In the rotating electrical machine 11, when electric power is supplied to the stator, the supplied electric power is converted into motive power and output to the rotating shaft 11a. When power is input to the rotating shaft 11a, the power is converted into electric power (power generation) and output to the stator.

  The stator of the rotating electrical machine 11 is electrically connected to a chargeable / dischargeable battery 16 via a power drive unit (hereinafter referred to as “PDU”) 15, and can transmit and receive electrical energy to and from the battery 16. It is. The PDU 15 is composed of an electric circuit such as an inverter. As shown in FIG. 2, an ECU 2 described later is electrically connected to the PDU 15. The ECU 2 controls the power supplied to the rotating electrical machine 11 and the power generated by the rotating electrical machine 11 by controlling the PDU 15.

  Hereinafter, converting electric power supplied to the rotating electrical machine 11 into power and outputting the power from the rotating shaft 11a is appropriately referred to as “powering”. Moreover, generating electricity with the rotating electrical machine 11 using the power input to the rotating shaft 11a and converting this power into electric power is referred to as “regeneration” as appropriate.

  In the driving force transmission device having the above-described configuration, the rotation speeds of the left side gear GL, the differential case DC, and the right side gear GR of the differential device DS are collinear with each other. In addition, the left drive gear WL is connected to the left side gear GL via the left output shaft SL, and the first gear G1 is provided so as to be integrally rotatable, so that the rotation of the three parties GL, WL and G1 can be performed. The numbers are equal to each other. Furthermore, since the engine 3 is connected to the differential case DC via the transmission 4 and the second gear G2 is provided so as to be integrally rotatable, if the shifting by the transmission 4 is ignored, the three cases The rotational speeds of DC, 3 and G2 are equal to each other. Further, since the right side gear GR is connected to the right drive wheel WR via the right output shaft SR, the rotational speeds of both GR and WR are equal to each other.

  Further, the rotation speeds of the sun gear S, the carrier C, and the ring gear R are collinear with each other. Further, since the sun gear S is provided integrally with the rotating shaft 11a of the rotating electrical machine 11, the rotational speed of the sun gear S and the rotational speed of the rotating electrical machine 11 are equal to each other. Further, since the carrier C is provided with the third gear G3 so as to be integrally rotatable, the rotational speeds of both C and G3 are equal to each other, and the ring gear R is provided with the fourth gear G4 so as to be integrally rotatable. Therefore, the rotational speeds of both R and G4 are equal to each other. Further, the third gear G3 meshes with the first gear G1, and the fourth gear G4 meshes with the second gear G2. From the above, the relationship between the rotational speeds of the various rotary elements in the driving force transmission device is expressed as in the alignment chart shown in FIG. 3, for example.

Here, the number of teeth of the sun gear S is ZS, the number of teeth of the ring gear R is ZR, and the number of teeth of the first to fourth gears G1, G2, G3, and G4 is ZG1, ZG2, ZG3, and ZG4, respectively. The gear teeth numbers ZS, ZR and ZG1 to ZG4 are set so that the sun gear S and the rotating electrical machine 11 are held in a stopped state when the rotation speeds of the left and right drive wheels WL and WR are equal to each other (the rotation speed is Set to 0). Specifically, the number of teeth ZS, ZR and ZG1 to ZG4 of these gears are set so that the following expression (6) is established.
ZG3 / ZG1 = (1 + ZS / ZR) × (ZG4 / ZG2) (6)

  As shown in FIG. 2, the ECU 2 receives a detection signal representing the steering angle θ of the vehicle handle (not shown) from the steering angle sensor 21, and a detection signal representing the vehicle speed VP of the vehicle from the vehicle speed sensor 22. A detection signal representing an operation amount (hereinafter referred to as “accelerator opening”) AP of an accelerator pedal (not shown) of the vehicle is input from the accelerator opening sensor 23. Further, a detection signal representing a current / voltage value input / output to / from the battery 16 is input from the current / voltage sensor 24 to the ECU 2. The ECU 2 calculates the state of charge of the battery 16 based on the detection signal from the current / voltage sensor 24.

  The ECU 2 is composed of a microcomputer including an I / O interface, CPU, RAM, ROM, and the like. The ECU 2 controls the rotating electrical machine 11 according to the control program stored in the ROM in accordance with the detection signals from the various sensors 21 to 24 described above. Thereby, various operations of the driving force transmission device are performed. Hereinafter, the operation of the driving force transmission device when the vehicle is traveling straight and when turning left and right will be described.

When the vehicle is traveling straight, the rotating electrical machine 11 is controlled so that neither power running nor regeneration is performed. The engine driving force of the engine 3 is transmitted to the left and right driving wheels WL and WR via the transmission 4 and the differential device DS. Accordingly, the vehicle moves forward by driving the left and right drive wheels WL and WR so as to rotate in the forward rotation direction. In this case, the torque distribution ratio to the left and right drive wheels WL and WR is 1: 1 as described above.

  Further, as described using the above formula (6), the number of teeth ZS of the sun gear gear S, the number of teeth ZR of the ring gear R, and the number of teeth ZG1 to ZG4 of the first to fourth gears G1 to G4 are set. When the vehicle travels straight, as shown in FIG. 3, the sun gear S and the rotating electrical machine 11 are held in a stopped state (the rotational speed is 0). 3 represents the output torque of the engine 3 after the shift (hereinafter referred to as “the engine torque after the shift”) transmitted to the differential case DC, and RlE and RrE represent the left as the engine torque TE after the shift is transmitted. It is reaction force torque which acts on the driving wheel WL and the right driving wheel WR, respectively.

When the vehicle turns left, as shown in FIG. 4, the rotation speed of the left drive wheel WL is lower than the rotation speed of the right drive wheel WR. As a result, the rotational speed of the carrier C connected to the left drive wheel WL via the first and third gears G1 and G3 decreases, and the sun gear S and the rotating shaft 11a of the rotating electrical machine 11 that have been stopped until then are reduced. Rotates in the forward direction. When increasing the driving force distributed to the right driving wheel WR, the rotating electrical machine 11 performs power running and controls the electric power supplied from the battery 16 to the rotating electrical machine 11. FIG. 5 shows the transmission state of the driving force between the various rotating elements in this case.

  As shown by the thick line with the hatched arrows in FIG. 5, when the vehicle turns left, the engine driving force is transmitted to the left and right drive wheels WL through the differential device DS, as in the case of the vehicle going straight. Is transmitted to the WR. Further, the driving force of the rotating electrical machine 11 by power running (hereinafter referred to as “motor driving force”) is transmitted to the sun gear S, and the ring gear is transmitted via the planetary gear PL using the driving force transmitted to the carrier C as a reaction force as will be described later. To R. That is, a driving force obtained by combining the motor driving force transmitted to the sun gear S and the driving force transmitted to the carrier C is transmitted to the ring gear R.

  The driving force transmitted to the ring gear R is transmitted to the differential case DC via the fourth gear G4 and the second gear G2, and via the pinion gear PI, the left and right side gears GL, GR, and the left and right output shafts SL, SR. , Transmitted to the left and right drive wheels WL, WR. Accordingly, part of the driving force transmitted to the left output shaft SL is transmitted to the carrier C via the first gear G1 and the third gear G3. As described above, when the vehicle turns left, as shown in FIG. 5, the driving force distributed to the right driving wheel WR becomes larger than that of the left driving wheel WL.

  FIG. 4 shows the balance of torque between the various rotary elements when the vehicle turns left. In the figure, TM is the output torque of the rotating electrical machine 11 (hereinafter referred to as “motor torque”). RC and RR are reaction torques acting on the carrier C and the ring gear R, respectively, as the motor torque TM is transmitted to the sun gear S. TC is a torque transmitted from the carrier C to the left output shaft SL along with the transmission of the motor torque TM, and in this case, a negative torque. Further, TR is a torque transmitted from the ring gear R to the differential case DC along with the transmission of the motor torque TM, and in this case, is a positive torque. RlR and RrR are reaction torques acting on the left and right drive wheels WL and WR as torque is transmitted from the ring gear R to the differential case DC. Other parameters are the same as in FIG.

  As is apparent from FIG. 4, when the vehicle turns left, torque transmitted to the left driving wheel WL (hereinafter referred to as “left driving wheel transmission torque”) is expressed by RlE + RlR−TC and applied to the right driving wheel WR. The transmitted torque (hereinafter referred to as “right drive wheel transmission torque”) is represented by RrE + RrR. In this case, as described above, since the torque transmitted to the differential case DC is distributed to the left and right drive wheels WL and WR at a distribution ratio of 1: 1, RlE = RrE and RlR = RrR are established. Therefore, the torque difference between the left and right drive wheels WL and WR (hereinafter referred to as “left and right wheel torque difference”) is represented by | (RlE + RlR−TC) − (RrE + RrR) | = | TC |.

  Here, as described above, TC is a negative torque that acts on the left output shaft SL from the carrier C as the motor torque TM is transmitted to the sun gear S. For this reason, the difference between the left and right wheel torques is determined by using the motor torque TM, the number of teeth ZS of the sun gear S, the number of teeth ZR of the ring gear R, the number of teeth ZG3 of the third gear G3, and the number of teeth ZG1 of the first gear G1. | = | (1 + ZR / ZS) × (ZG1 / ZG3) TM | Therefore, by controlling the motor torque TM via the electric power supplied to the rotating electrical machine 11, the left and right wheel torque difference can be freely controlled, and the distribution of the driving force to the left and right driving wheels WL and WR is freely controlled. be able to.

When the vehicle turns right, as shown in FIG. 6, the rotation speed of the left drive wheel WL is higher than the rotation speed of the right drive wheel WR, thereby being connected to the left drive wheel WL. As the rotational speed of the carrier C increases, the sun gear S and the rotating shaft 11a of the rotating electrical machine 11 that have been stopped until then rotate in the reverse direction. When increasing the driving force distributed to the left driving wheel WL, the rotating electrical machine 11 performs power running and controls the electric power supplied from the battery 16 to the rotating electrical machine 11. FIG. 7 shows the transmission state of the driving force between the various rotating elements in this case.

  As indicated by the hatched thick line with arrows in FIG. 7, when the vehicle turns right, the engine driving force is transmitted to the left and right drive wheels WL via the differential device DS, as in the case of straight traveling of the vehicle. , Transmitted to WR. Further, the motor driving force (the driving force of the rotating electrical machine 11 by powering) is transmitted to the sun gear S and is transmitted to the carrier C through the planetary gear PL using the driving force transmitted to the ring gear R as a reaction force as will be described later. The That is, a driving force obtained by combining the motor driving force transmitted to the sun gear S and the driving force transmitted to the ring gear R is transmitted to the carrier C.

  Further, the driving force transmitted to the carrier C is transmitted to the left output shaft SL via the third gear G3 and the first gear G1, and further transmitted to the left driving wheel WL. Accordingly, part of the driving force transmitted to the differential case DC is transmitted to the ring gear R via the second gear G2 and the fourth gear G4. As described above, when the vehicle turns right, as shown in FIG. 7, the driving force distributed to the left driving wheel WL becomes larger than that of the right driving wheel WR.

  FIG. 6 shows a torque balance relationship between various types of rotating elements when the vehicle turns right. The various parameters in the figure are the same as in the case of the left turn shown in FIG. Unlike the case of FIG. 4, TC, that is, the torque transmitted from the carrier C to the left output shaft SL along with the transmission of the motor torque TM is a positive torque, and TR, that is, along with the transmission of the motor torque TM. The torque transmitted from the ring gear R to the differential case DC is a negative torque.

  As is apparent from FIG. 6, when the vehicle turns right, the left drive wheel transmission torque is represented by RlE−RlR + TC, and the right drive wheel transmission torque is represented by RrE−RrR. Also in this case, RlE = RrE and RlR = RrR hold as in the case of FIG. Therefore, the difference between the left and right wheel torques (torque difference between the left and right drive wheels WL and WR) is, in this case also, | (RlE−RlR + TC) − (RrE−RrR) | = | TC | = | (1 + ZR / ZS ) × (ZG1 / ZG3) TM |. Therefore, by controlling the motor torque TM via the electric power supplied to the rotating electrical machine 11, the left and right wheel torque difference can be freely controlled, and the distribution of the driving force to the left and right driving wheels WL and WR is freely controlled. be able to.

  When the vehicle turns left and right, the electric power supplied to the rotating electrical machine 11 is controlled according to the detected steering angle θ, the vehicle speed VP, the accelerator pedal opening AP, the state of charge of the battery 16, and the like. The driving force distributed to the left and right drive wheels WL, WR is controlled.

  Further, when the vehicle turns left and right, regeneration may be performed without powering the rotating electrical machine 11. In this case, the left and right drive wheels WL and WR are controlled by controlling the power regenerated by the rotating electrical machine 11. The driving force distributed to can be controlled. When regeneration is performed by the rotating electrical machine 11 when turning left, the driving force distributed to the left drive wheel WL is larger than that of the right drive wheel WR, and when regeneration is performed by the rotating electrical machine 11 when turning right The driving force distributed to the right driving wheel WR becomes larger than that of the left driving wheel WL.

  Moreover, the correspondence between the various elements in the first embodiment and the various elements in the present invention is as follows. That is, the left and right drive wheels WL and WR in the first embodiment correspond to the first and second drive wheels in the present invention, respectively, and the engine 3 in the first embodiment corresponds to the vehicle drive source in the present invention. To do. Further, the differential device DS in the first embodiment corresponds to the first differential device in the present invention, and the left side gear GL, the differential case DC, and the right side gear GR in the first embodiment are the first rotating element in the present invention. , Corresponding to the second rotation element and the third rotation element, respectively.

  Further, the planetary gear device PS in the first embodiment corresponds to the second differential device in the present invention, and the sun gear S, the carrier C, and the ring gear R in the first embodiment are the fourth rotating element, This corresponds to the 5th rotation element and the 6th rotation element, respectively. The rotating electrical machine 11 in the first embodiment corresponds to the distribution drive source in the present invention.

  As described above, according to the first embodiment, the left and right side gears GL and GR of the differential device DS are coupled to the left and right drive wheels WL and WR via the left and right output shafts SL and SR, respectively. The differential case DC is connected to the engine 3. Further, the first and second gears G1 and G2 are rotatably provided integrally with the left side gear GL and the differential case DC, respectively. Further, the sun gear S of the planetary gear device PS is connected to the rotating electrical machine 11, and the carrier C and the ring gear R are provided with third and fourth gears G3 and G4, respectively, so as to be rotatable together. Further, the first and third gears G1 and G3 mesh with each other, and the second and fourth gears G2 and G4 mesh with each other.

  Further, as described with reference to FIG. 7, with the generation of the motor driving force, the driving force transmitted to the carrier C via the sun gear S and the planetary gear PL, the ring gear R, and the planetary gear PL are transmitted to the left driving wheel WL. The driving force obtained by synthesizing the driving force transmitted to the carrier C through the first gear G3 is transmitted through the third gear G3, the first gear G1, and the left output shaft SL. In this case, the number of gear meshes directly related to transmission of the driving force to the left drive wheel WL (hereinafter referred to as “left gear mesh number”) is “mesh between the sun gear S and the planetary gear PL. "I", "meshing between the ring gear R and the planetary gear PL" and "meshing between the third gear G3 and the first gear G1".

  Further, as the motor driving force is generated, the left and right driving wheels WL and WR include the sun gear S, planetary gear PL, ring gear R, fourth gear G4, second gear G2, differential case DC, pinion gear PI, left and right side gears GL, Negative driving force is transmitted through the GR and the left and right output shafts SL and SR, respectively. In this case, the meshing number of gears directly related to transmission of driving force to the right driving wheel WR (hereinafter referred to as “gearing number for right driving wheel”) is “meshing between the sun gear S and the planetary gear PL. ”,“ Meshing between planetary gear PL and ring gear R ”,“ meshing between fourth gear G4 and second gear G2 ”,“ meshing between pinion gear PI and left side gear GL ”and“ pinion gear PI ” Between the right side gear GR and the right side gear GR ”.

  As described above, according to the first embodiment, the number of meshing gears between the carrier C and the differential device DS is “meshing between the third gear G3 and the first gear G1”. In addition, the number of meshes between the ring gear R and the differential device DS is also "one mesh between the fourth gear G4 and the second gear G2". Thus, unlike the conventional case described above, the difference between the number of left drive wheel gear meshes and the number of right drive wheel gear meshes can be reduced. Specifically, as is apparent from the number of gear engagements described above, in the first embodiment, the difference between the number of left drive wheel gear engagements and the right drive wheel gear engagement is | 3-5 | = “2”, whereas, as described above, in the conventional driving force transmission device, “4”. As is apparent from a comparison between FIG. 5 and FIG. 7, this applies not only when the vehicle turns right as shown in FIG. 7, but also when the vehicle turns left as shown in FIG. Therefore, it is possible to improve the responsiveness of the driving force distribution to the left and right drive wheels WL and WR using the rotating electrical machine 11.

  Further, unlike the conventional case described above, the idler shaft is is not required, so that the apparatus can be reduced in size and the manufacturing cost can be reduced accordingly.

  Further, when the left and right drive wheels WL and WR are driven by transmission of driving force from the engine 3 via the differential device DS, since the various rotating elements are connected as described above, the engine driving force is reduced. In some cases, the electric rotating machine 11 is transmitted to the rotating electric machine 11 and dragged. According to the first embodiment, as shown in FIG. 3, the sun gear S and the rotating electrical machine 11 are held in a stopped state when the vehicle is traveling straight and the left and right drive wheels WL and WR have the same rotation speed. As described above, since the number of teeth ZS of the sun gear S, the number of teeth ZR of the ring gear R, and the number of teeth ZG1 to ZG4 of the first gear G1 to the fourth gear G4 are set (formula (6)), the rotation described above. The drag of the electric machine 11 can be prevented, thereby improving the controllability of the vehicle.

  Since the third gear G3 is engaged with the first gear G1, the number of teeth ZGA of the first gear G1 is equal to the number of teeth ZGA of one gear in the equation (5) described in the explanation of claim 3. Corresponds. Further, since the fourth gear G4 is engaged with the second gear G2, the number of teeth ZG2 of the second gear G2 corresponds to the number of teeth ZGB of the other gear in the equation (5). As is clear from the above, the setting of each gear based on the expression (6) corresponds to the setting of the number of teeth of each gear in the invention according to claim 3.

  As shown in FIG. 3, in the first embodiment, a differential case DC is used as an object to which the ring gear R is connected. Unlike the first embodiment, when the right side gear GR connected to the right drive wheel WR is used as an object to which the ring gear R is connected, the driving force to the left and right drive wheels WL and WR using the rotating electrical machine 11 During the distribution of torque, torque is exchanged with the ring gear R directly to the right drive wheel WR, so that the left-right wheel torque difference becomes relatively large.

  According to the first embodiment, since the differential case DC is used as an object to which the ring gear R is connected, torque between the ring gear R and the right and left driving wheels WL and WR using the rotating electrical machine 11 is distributed. Can be divided into left and right drive wheels WL and WR. As a result, the difference between the left and right wheel torques can be reduced with respect to the motor torque TM having the same magnitude, so that the drive force can be more finely distributed to the left and right drive wheels WL and WR.

  8 to 10 show first to third modifications of the first embodiment. In these FIGS. 8 to 10, the same components as those of the first embodiment are denoted by the same reference numerals. doing. Hereinafter, these first to third modifications will be described in order. The first modification shown in FIG. 8 is an example in which the driving force transmission device is applied to a vehicle of the type in which the propeller shaft 31 is connected to the output shaft 4a of the transmission 4 described above. A gear 31a is integrally provided on the propeller shaft 31, and this gear 31a is a bevel gear. Further, the differential case DC is integrally provided with a gear 32 instead of the gear 5. The gear 32 is a ring-shaped bevel gear and meshes with the gear 31a. These gears 31a and 32 constitute a hypoid gear.

  As shown in FIG. 8, the propeller shaft 31, the rotating electrical machine 11 and the planetary gear device PS are arranged so as to partially overlap each other in the axial direction of the both 11 and PS. The unevenness of the housing (not shown) can be reduced, and as a result, the mountability of the driving force transmission device can be improved.

  The second modification shown in FIG. 9 is an example in which the driving force transmission device is applied to a vehicle that uses the rotating electrical machine 41 as a driving source instead of the engine 3. The rotating electrical machine 41 is an AC motor similar to the rotating electrical machine 11. A rotating shaft 41a of the rotating electrical machine 41 is integrally provided with a gear 41b, and the gear 41b meshes with the first gear 42a. The first gear 42 a is integrally provided at one end of the idler shaft 42, and the second gear 42 b is integrally provided at the other end of the idler shaft 42. The second gear 42b meshes with the gear 5 provided in the above-described differential case DC. The driving force of the rotating electrical machine 41 is transmitted to the differential case DC while being decelerated by the gear 41b and the gear 5, and is further transmitted to the left and right driving wheels WL and WR. In this second modification, the rotating electrical machine 41 corresponds to the vehicle drive source in the present invention.

  As shown in FIG. 9, the rotating electrical machine 41 and the planetary gear device PS are arranged so as to partially overlap each other in the axial direction thereof, whereby the unevenness of the housing (not shown) of the driving force transmission device can be reduced. As a result, the mounting ability of the driving force transmission device can be improved.

  The third modification shown in FIG. 10 is an example in which the driving force transmission device is applied to a vehicle that uses the rotating electrical machine 51 as a drive source instead of the engine 3 as in the second modification. The rotating electrical machine 51 is an AC motor similar to the rotating electrical machine 11, and has a hollow rotating shaft 51a. A right output shaft SR is relatively rotatably disposed inside the rotating shaft 51a. Yes. The rotation shaft 51a is integrally provided with a gear 51b, and the gear 51b meshes with the first gear 52a.

  The first gear 52 a is integrally provided at one end of the idler shaft 52, and the second gear 52 b is integrally provided at the other end of the idler shaft 52. The second gear 52b meshes with the gear 5 provided in the above-described differential case DC. The driving force of the rotating electrical machine 51 is transmitted to the differential case DC while being decelerated by the gears 51b and 5 and further transmitted to the left and right drive wheels WL and WR. In the third modification, the rotating electrical machine 51 corresponds to the vehicle drive source in the present invention.

  As shown in FIG. 10, the idler shaft 52 and the planetary gear device PS are arranged so as to overlap each other in the axial direction thereof, thereby reducing the unevenness of the housing (not shown) of the driving force transmission device, As a result, the mountability of the driving force transmission device can be improved.

  Next, a driving force transmission device according to a second embodiment of the present invention will be described with reference to FIGS. In the driving force transmission device according to the second embodiment, the third and fourth gears G3 ′ and G4 ′ are not the first and second gears G1 ′ and G2 ′ as compared with the first embodiment. Conversely, the second and first gears G2 ′ and G1 ′ are different from each other. In these FIGS. 11-16, the same code | symbol is attached | subjected about the same component as 1st Embodiment. Hereinafter, a description will be given focusing on differences from the first embodiment.

  Similar to the first embodiment, the first gear G1 'is provided integrally with the left output shaft SL, and the second gear G2' is provided integrally with the differential case DC so as to be rotatable. The base Cc of the carrier C is formed in a disc shape, and the third gear G3 'is integrally provided on the base Cc. The carrier C is rotatable integrally with the third gear G3 '. A fourth gear G4 'is attached to the outer peripheral portion of the ring gear R via a flange or a hollow rotating shaft, and both the R and G4' can be rotated together. The third gear G3 'meshes with the second gear G2', and the fourth gear G4 'meshes with the first gear G1'. From the above configuration, the rotational speed relationship between the various rotary elements in the driving force transmission apparatus according to the second embodiment is expressed as in a collinear chart shown in FIG. 12, for example.

As in the first embodiment, the number of teeth of the sun gear S is ZS, the number of teeth of the ring gear R is ZR, and the number of teeth of the first to fourth gears G1 ′, G2 ′, G3 ′, and G4 ′ is ZG1 ′, ZG2, respectively. ', ZG3' and ZG4 '. The gear teeth numbers ZS, ZR and ZG1 ′ to ZG4 ′ are set so that the sun gear S and the rotating electrical machine 11 are held in a stopped state when the rotational speeds of the left and right drive wheels WL, WR are equal to each other (rotation). The number is set to be 0). Specifically, the number of teeth ZS, ZR and ZG1 ′ to ZG4 ′ of these gears are set so that the following expression (7) is established.
ZG3 ′ / ZG2 ′ = (1 + ZS / ZR) × (ZG4 ′ / ZG1 ′) (7)

  Next, the operation of the driving force transmission device when the vehicle goes straight and when turning left and right will be described.

As in the first embodiment, the rotating electrical machine 11 is controlled so as not to perform both power running and regeneration. Further, the engine driving force is transmitted to the left and right driving wheels WL and WR via the transmission 4 and the differential device DS. As a result, the vehicle moves forward by driving the drive wheels WL and WR so as to rotate in the forward rotation direction.

  Further, as described using the equation (7), the number of teeth ZS of the sun gear gear S, the number of teeth ZR of the ring gear R, and the number of teeth ZG1 ′ to ZG4 ′ of the first to fourth gears G1 ′ to G4 ′ are set. Therefore, when the vehicle travels straight, as shown in FIG. 12, the sun gear S and the rotating electrical machine 11 are held in a stopped state (the rotational speed is 0). The various parameters in FIG. 12 are as described with reference to FIG.

When the vehicle is turning left, as shown in FIG. 13, the rotation speed of the left drive wheel WL is lower than the rotation speed of the right drive wheel WR. As a result, the rotational speed of the ring gear R connected to the left drive wheel WL via the first and fourth gears G1 ′ and G4 ′ decreases, and the sun gear S and the rotating electrical machine 11 that have been stopped until then are rotated. The shaft 11a rotates in the reverse direction. When increasing the driving force distributed to the right driving wheel WR, the rotating electrical machine 11 performs power running and controls the electric power supplied from the battery 16 to the rotating electrical machine 11. FIG. 14 shows the transmission state of the driving force between the various rotating elements in this case.

  As shown by the thick line with the hatched arrows in FIG. 14, when the vehicle turns left, the engine driving force is transmitted to the left and right drive wheels WL via the differential device DS, as in the case of the vehicle going straight. Is transmitted to the WR. Further, the motor driving force is transmitted to the sun gear S, and is transmitted to the carrier C through the planetary gear PL using the driving force transmitted to the ring gear R as a reaction force as will be described later. That is, a driving force obtained by combining the motor driving force transmitted to the sun gear S and the driving force transmitted to the ring gear R is transmitted to the carrier C.

  The driving force transmitted to the carrier C is transmitted to the differential case DC via the third gear G3 ′ and the second gear G2 ′, and the pinion gear PI, the left and right side gears GL and GR, and the left and right output shafts SL and SR are transmitted. Via the left and right drive wheels WL and WR. Accordingly, part of the driving force transmitted to the left output shaft SL is transmitted to the ring gear R via the first gear G1 'and the fourth gear G4'. As described above, when the vehicle turns left, as shown in FIG. 14, the driving force distributed to the right driving wheel WR becomes larger than that of the left driving wheel WL.

  FIG. 13 shows a torque balance relationship between various rotating elements when the vehicle turns to the left. In FIG. 13, TC ′ represents the carrier C as the motor torque TM is transmitted to the sun gear S. To the differential case DC, and in this case, a positive torque. Further, TR ′ is a torque transmitted from the ring gear R to the left output shaft SL along with the transmission of the motor torque TM, and in this case, a negative torque. RlC and RrC are reaction torques acting on the left and right drive wheels WL and WR as torque is transmitted from the carrier C to the differential case DC. Other parameters are the same as in FIG.

  As is apparent from FIG. 13, when the vehicle turns left, the left drive wheel transmission torque is represented by RlE + R1C−TR ′, and the right drive wheel transmission torque is represented by RrE + RrC. In this case, as described above, since the torque transmitted to the differential case DC is distributed to the left and right drive wheels WL and WR at a distribution ratio of 1: 1, RlE = RrE and RlC = RrC are established. Therefore, the left-right wheel torque difference (torque difference between the left and right drive wheels WL, WR) is represented by | (RlE + RlC-TR ′) − (RrE + RrC) | = | TR ′ |.

  Here, as described above, TR ′ is a negative torque that acts on the left output shaft SL from the ring gear R as the motor torque TM is transmitted. For this reason, the left and right wheel torque difference uses the motor torque TM, the number of teeth ZS of the sun gear S, the number of teeth ZR of the ring gear R, the number of teeth ZG4 ′ of the fourth gear G4 ′, and the number of teeth ZG1 ′ of the first gear G1 ′. | TR ′ | = | (ZR / ZS) × (ZG1 ′ / ZG4 ′) TM | Therefore, by controlling the motor torque TM via the electric power supplied to the rotating electrical machine 11, the left and right wheel torque difference can be freely controlled, and the distribution of the driving force to the left and right driving wheels WL and WR is freely controlled. be able to.

When the vehicle turns right, as shown in FIG. 15, the rotation speed of the left drive wheel WL is higher than the rotation speed of the right drive wheel WR, thereby being connected to the left drive wheel WL. As the rotational speed of the ring gear R increases, the sun gear S and the rotating shaft 11a of the rotating electrical machine 11 that have been stopped until then rotate in the forward rotation direction. When increasing the driving force distributed to the left driving wheel WL, the rotating electrical machine 11 performs power running and controls the electric power supplied from the battery 16 to the rotating electrical machine 11. FIG. 16 shows the state of transmission of the driving force between the various rotating elements in this case.

  As indicated by the hatched thick line with arrows in FIG. 16, when the vehicle turns right, the engine driving force is transmitted to the left and right drive wheels WL via the differential device DS, as in the case of straight traveling of the vehicle. , Transmitted to WR. Further, the motor driving force is transmitted to the sun gear S, and is transmitted to the ring gear R through the planetary gear PL using the driving force transmitted to the carrier C as a reaction force as will be described later. That is, a driving force obtained by combining the motor driving force transmitted to the sun gear S and the driving force transmitted to the carrier C is transmitted to the ring gear R.

  The driving force transmitted to the ring gear R is transmitted to the left output shaft SL via the fourth gear G4 'and the first gear G1', and further transmitted to the left driving wheel WL. Accordingly, part of the driving force transmitted to the differential case DC is transmitted to the carrier C via the second gear G2 'and the third gear G3'. Thus, when the vehicle turns right, as shown in FIG. 16, the driving force distributed to the left driving wheel WL becomes larger than that of the right driving wheel WR.

  FIG. 15 shows a torque balance relationship between various types of rotating elements when the vehicle turns right. The various parameters in the figure are the same as in the case of the left turn shown in FIG. Unlike the case of FIG. 13, TC ′, that is, the torque transmitted from the carrier C to the differential case DC along with the transmission of the motor torque TM is a negative torque, and TR ′, that is, with the transmission of the motor torque TM. The torque transmitted from the ring gear R to the left output shaft SL is a positive torque.

  As is apparent from FIG. 15, when the vehicle turns right, the left drive wheel transmission torque is represented by RlE−R1C + TR ′, and the right drive wheel transmission torque is represented by RrE−RrC. Also in this case, RlE = RrE and RlC = RrC are established as in FIG. Therefore, the difference between the left and right wheel torques is also expressed by | (RlE−RlC + TR ′) − (RrE−RrC) | = | TR ′ | = | (ZR / ZS) × (ZG1 ′ / ZG4 ′) TM | expressed. Therefore, by controlling the motor torque TM via the electric power supplied to the rotating electrical machine 11, the left and right wheel torque difference can be freely controlled, and the distribution of the driving force to the left and right driving wheels WL and WR is freely controlled. be able to.

  As in the first embodiment, when the vehicle turns left and right, the electric power supplied to the rotating electrical machine 11 depends on the detected steering angle θ, the vehicle speed VP, the accelerator pedal opening AP, the state of charge of the battery 16, and the like. Thus, the driving force distributed to the left and right driving wheels WL, WR is controlled.

  Further, when the vehicle turns left and right, regeneration may be performed without powering the rotating electrical machine 11. In this case, the left and right drive wheels WL and WR are controlled by controlling the power regenerated by the rotating electrical machine 11. The driving force distributed to can be controlled. When regeneration is performed by the rotating electrical machine 11 when turning left, the driving force distributed to the left drive wheel WL is larger than that of the right drive wheel WR, and when regeneration is performed by the rotating electrical machine 11 when turning right The driving force distributed to the right driving wheel WR becomes larger than that of the left driving wheel WL.

  As described above, according to the second embodiment, the left and right side gears GL and GR of the differential device DS are connected to the left and right drive wheels WL and WR via the left and right output shafts SL and SR, respectively. The differential case DC is connected to the engine 3. Further, the first and second gears G1 'and G2' are rotatably provided integrally with the left side gear GL and the differential case DC, respectively. Further, the sun gear S of the planetary gear device PS is connected to the rotating electrical machine 11, and the carrier C and the ring gear R are provided with third and fourth gears G3 'and G4', respectively, so as to be rotatable together. Further, the first and fourth gears G1 'and G4' are engaged with each other, and the second and third gears G2 'and G3' are engaged with each other.

  Further, as described with reference to FIG. 16, with the generation of the motor driving force, the left driving wheel WL includes the sun gear S, the planetary gear PL, the ring gear R, the fourth gear G4 ′, the first gear G1 ′, and the left A driving force is transmitted through the output shaft SL. Thus, the number of meshes for the left drive wheel (the number of meshes of the gear directly related to transmission of the driving force to the left drive wheel WL) is “mesh between the sun gear S and the planetary gear PL”. There are three in total, “meshing between planetary gear PL and ring gear R” and “meshing between fourth gear G4 ′ and first gear G1 ′”.

  Further, as the motor driving force is generated, the left and right driving wheels WL and WR include the sun gear S, the planetary gear PL, the carrier C, the third gear G3 ′, the second gear G2 ′, the differential case DC, the pinion gear PI, and the left and right side gears. Negative driving force is transmitted through GL, GR and left and right output shafts SL, SR, respectively. In this case, since the planetary gear PL is engaged with both the sun gear S and the ring gear R, the transmission between the sun gear S and the carrier C via the planetary gear PL is related to the engagement between the planetary gear PL and the ring gear R. To do. From the above, the gear meshing number for the right driving wheel (the gear meshing number directly related to transmission of the driving force to the right driving wheel WR) is “meshing between the sun gear S and the planetary gear PL” and “ "Meshing between planetary gear PL and ring gear R", "meshing between third gear G3 'and second gear G2'", "meshing between pinion gear PI and left side gear GL" and "pinion gear PI and right The total number of engagements between the side gears GR is five.

  As described above, according to the second embodiment, the number of gear meshes between the carrier C and the differential device DS is “mesh between the third gear G3 ′ and the second gear G2 ′”. The number of meshes between the ring gear R and the differential device DS is also “one mesh between the fourth gear G4 ′ and the first gear G1 ′”. Thus, unlike the conventional case described above, the difference between the number of left drive wheel gear meshes and the number of right drive wheel gear meshes can be reduced. Specifically, in the second embodiment, the difference between the number of gear engagement for the left driving wheel and the number of gear engagement for the right driving wheel is | 3-5 | = “2”, as described above. In the conventional driving force transmission device, it is “4”. As apparent from the comparison between FIG. 14 and FIG. 16, this applies not only when the vehicle turns right as shown in FIG. 16, but also when the vehicle turns left as shown in FIG. Therefore, it is possible to improve the responsiveness of the driving force distribution to the left and right drive wheels WL and WR using the rotating electrical machine 11.

  Further, as in the first embodiment, the conventional idler shaft is is unnecessary, so that the apparatus can be reduced in size and the manufacturing cost can be reduced accordingly.

  Further, when the left and right drive wheels WL and WR are driven by transmission of driving force from the engine 3 via the differential device DS, since the various rotating elements are connected as described above, the engine driving force is reduced. In some cases, the electric rotating machine 11 is transmitted to the rotating electric machine 11 and dragged. According to the second embodiment, as shown in FIG. 12, the sun gear S and the rotating electrical machine 11 are held in a stopped state when the rotational speed of the left and right drive wheels WL and WR is equal to each other when the vehicle is traveling straight. As described above, the number of teeth ZS of the sun gear S, the number of teeth ZR of the ring gear R, and the number of teeth ZG1 ′ to ZG4 ′ of the first gear G1 ′ to the fourth gear G4 ′ are set (the above formula (7)). The drag of the rotating electrical machine 11 described above can be prevented, thereby improving the controllability of the vehicle.

  Since the third gear G3 ′ is in mesh with the second gear G2 ′, the number of teeth ZGA of one gear in the equation (5) described in the explanation of claim 3 is the same as that of the second gear G2 ′. This corresponds to the number of teeth ZG2 ′. Further, since the fourth gear G4 'is engaged with the first gear G1', the number of teeth ZG1 'of the first gear G1' corresponds to the number of teeth ZGB of the other gear in the equation (5). As is clear from the above, the setting of each gear based on Expression (7) corresponds to the setting of the number of teeth of each gear in the invention according to claim 3.

  As shown in FIG. 12, in the second embodiment, a differential case DC is used as a target to which the carrier C is connected. Unlike the second embodiment, when the right side gear GR connected to the right drive wheel WR is used as an object to which the carrier C is connected, the driving force to the left and right drive wheels WL and WR using the rotating electrical machine 11 is used. During the distribution, torque exchange with the carrier C is performed directly on the right drive wheel WR, so that the left-right wheel torque difference is relatively large.

  According to the second embodiment, since the differential case DC is used as an object to which the carrier C is connected, the torque between the carrier C and the right and left driving wheels WL and WR using the rotating electrical machine 11 during the distribution of the driving force. Can be divided into left and right drive wheels WL and WR. As a result, the difference between the left and right wheel torques can be reduced with respect to the motor torque TM having the same magnitude, so that the drive force can be more finely distributed to the left and right drive wheels WL and WR.

  In addition, as described with reference to FIGS. 4, 6, 13 and 15, the difference between the left and right wheel torques is generated by transmission / reception of torque through the carrier C in the first embodiment, whereas in the second embodiment. In the form, the torque is transmitted and received through the ring gear R. Therefore, the left and right wheel torque difference in the first embodiment is represented by | TC | = | (1 + ZR / ZS) × (ZG1 / ZG3) TM |, whereas the left and right wheel torque difference in the second embodiment is , | TR ′ | = | (ZR / ZS) × (ZG1 ′ / ZG4 ′) TM |, which is smaller than that of the first embodiment. Therefore, as compared with the first embodiment, it is possible to finely distribute the driving force to the left and right driving wheels WL and WR.

  In the second embodiment, similarly to the first embodiment, the driving force transmission device is applied to a vehicle of a type in which the gear 4b integrated with the output shaft 4a of the transmission 4 meshes with the gear 5 integrated with the differential case DC. However, as in the first modification (FIG. 8) of the first embodiment, the present invention may be applied to a vehicle in which the propeller shaft 31 is connected to the output shaft 4a.

  The second embodiment is an example in which the driving force transmission device is applied to a vehicle on which the engine 3 is mounted as a driving source, but the second and third modifications of the first embodiment (FIGS. 9 and 10). ), The present invention may be applied to a vehicle on which rotating electrical machines 41 and 51 are mounted as drive sources.

  Note that the present invention is not limited to the first and second embodiments described (including modifications, and hereinafter collectively referred to as “embodiments”), and can be implemented in various modes. For example, in the embodiment, the sun gear S is used as the fourth rotating element and the ring gear R is used as the sixth rotating element in the present invention, but conversely, the ring gear R is used as the fourth rotating element. A sun gear S may be used as the rotating element. In other words, the ring gear R may be coupled to the rotating electrical machine 11 and the fourth gear G4 (G4 ') may be rotatably provided integrally with the sun gear S.

  In the embodiment, the sun gear S is provided integrally with the rotating shaft 11a of the rotating electrical machine 11, but may be coupled to the rotating shaft 11a via a gear or the like. This also applies to the connection between the left and right output shafts SL, SR and the left and right drive wheels WL, WR. Further, in the embodiment, the bevel gear type differential device DS is used as the first differential device in the present invention. However, the first to first gears that are capable of transmitting power between each other and have rotational speeds that are collinear with each other. Another device having the third rotating element, for example, a single pinion type or double pinion type planetary gear device may be used. The same applies to the second differential device. That is, in the embodiment, the single pinion type planetary gear device PS is used as the second differential device in the present invention. However, for example, a bevel gear type differential device or a double pinion type planetary gear device may be used. Good.

  In the embodiment, the rotating electrical machine 11 configured to be capable of powering and regeneration is used as the distribution drive source in the present invention. However, other devices that can output the driving force, for example, an electric motor capable of only powering. Alternatively, a hydraulic motor or the like may be used. Furthermore, although embodiment is an example which applied this invention to the vehicle by which the engine 3 which is a gasoline engine, or the rotary electric machine 41 (51) is mounted as a vehicle drive source, this invention is not limited to this, You may apply to the vehicle by which a diesel engine, a CNG engine, an external combustion engine, etc. are mounted. In the embodiment, the first and second drive wheels in the present invention are the left and right drive wheels WL and WR, but may be front and rear drive wheels in a front and rear wheel drive type vehicle, for example. In addition, it is possible to appropriately change the detailed configuration within the scope of the gist of the present invention.

WL Left drive wheel (first drive wheel)
WR Right drive wheel (second drive wheel)
3 Engine (vehicle drive source)
DS differential (first differential)
GL Left side gear (first rotating element)
DC differential case (second rotating element)
GR Right side gear (third rotation element)
PS planetary gear unit (second differential)
S Sun gear (fourth rotating element)
C carrier (5th rotating element)
R ring gear (sixth rotating element)
11 Rotating machine (distribution drive source)
G1 1st gear G2 2nd gear G3 3rd gear G4 4th gear 41 Rotating electric machine (vehicle drive source)
51 Rotating electric machine (vehicle drive source)
G1 'first gear G2' second gear G3 'third gear G4' fourth gear

Claims (4)

A driving force transmission device for transmitting a driving force from a vehicle driving source to first and second driving wheels for propelling a vehicle,
The first rotating element, the second rotating element, and the third rotating element that can transmit power between each other, and the rotational speeds of the first to third rotating elements are arranged on a single straight line in the collinear diagram. A first differential configured to satisfy a collinear relationship arranged in order;
A first gear provided to be integrally rotatable with the first rotating element;
A second gear provided to be rotatable integrally with the second rotating element,
The first rotating element is connected to the first driving wheel, the second rotating element is connected to the vehicle drive source, and the third rotating element is connected to the second driving wheel,
A fourth rotating element, a fifth rotating element, and a sixth rotating element capable of transmitting power between each other, and the rotational speeds of the fourth to sixth rotating elements are arranged on a single straight line in a collinear diagram; A second differential configured to satisfy a collinear relationship arranged in order;
A distribution drive source coupled to the fourth rotation element so as to output a drive force;
A third gear provided integrally with the fifth rotation element so as to freely rotate, and meshing with one of the first and second gears;
A drive force transmission device, further comprising: a fourth gear that is integrally rotatable with the sixth rotation element and meshes with the other of the first and second gears.   The first to fourth gears and the second differential are configured so that the fourth rotating element is held in a stopped state when the rotation speeds of the first and second drive wheels are equal to each other. The driving force transmission device according to claim 1, wherein The second differential device rotatably supports a sun gear as the fourth rotating element, a ring gear as the sixth rotating element provided on the outer periphery of the sun gear, and a planetary gear meshing with the sun gear and the ring gear. A single pinion type planetary gear device having a carrier as the fifth rotating element;
The number of teeth of the sun gear is ZS, the number of teeth of the ring gear is ZR, the number of teeth of the first and second gears is ZGA, and the number of teeth of the first and second gears is ZGB. When the number of teeth of the third gear is ZG3 and the number of teeth of the fourth gear is ZG4, the sun gear is set so that ZG3 / ZGA = (1 + ZS / ZR) × (ZG4 / ZGB) is established. Number of teeth ZS, number of teeth ZR of the ring gear, number of teeth ZGA of the first and second gears, number of teeth ZGB of the other of the first and second gears, number of teeth ZG3 of the third gear And the number of teeth ZG4 of the 4th gear is set up, The driving force transmission device according to claim 1 or 2 characterized by things.   4. The driving force transmission device according to claim 1, wherein the distribution drive source is a rotating electrical machine.

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