Unit

Abstract

[Problem] To reduce the step ratio during gear shifting in a unit having a power transmission mechanism therein. [Solution] This unit is provided with an input element, an output element, and a gear device in which a first rotation site, second rotation site, third rotation site, and fourth rotation site are arranged in the stated order in a velocity diagram. The input element can connect to the first rotation site and to the second rotation site, the output element is connected to the third rotation site, and the fourth rotation element can switch between a rotating state and a non-rotating state. The gear device is provided with a first planetary gear mechanism and a secondary planetary gear mechanism. The first rotation site is constituted of a third rotational element. The second rotation site is constituted by linking a second rotational element and a sixth rotational element. The third rotation site is constituted of a fifth rotational element. The fourth rotation site is constituted by linking a first rotational element and a fourth rotational element.

Description

unit

[0001] The present invention relates to a unit having a power transmission mechanism therein.

[0002] Patent Document 1 discloses an automatic transmission unit for an electric vehicle with two forward speeds, which can achieve first speed and second speed, which has a smaller gear ratio (= input rotation speed / output rotation speed) than first speed, by switching the engagement state of two friction clutches.

[0003] Similar units are also disclosed in US Pat. Nos. 5,699,222, 5,999,232, 5,999,247 and 5,999,252.

[0004] German Patent Application Publication No. 102019116360 German Patent Application Publication No. 102019119951 Chinese Patent No. 106195194 Chinese Utility Model No. 206000959

[0005] In an automatic transmission unit for an electric vehicle with two forward speeds, the torque amplification effect due to deceleration increases as the gear ratio of first gear increases, so the maximum torque of the motor can be reduced as the gear ratio of first gear increases, allowing a smaller motor to be selected.In contrast, the smaller the gear ratio of second gear, the lower the motor rotation speed when achieving a certain vehicle speed, which is advantageous for high-speed cruising.

[0006] However, if the gear ratios for first and second gears are set based on the above design concept, the gear ratio (= gear ratio for first gear / gear ratio for second gear) when switching between first and second gears becomes large, resulting in a large gear change shock.

[0007] The present invention has been made in view of these technical problems, and has as its object to reduce the gear ratio during gear change in a unit having a power transmission mechanism therein.

[0008] According to one aspect of the present invention, there is provided a gear train comprising: an input element; an output element; and a gear train having a first rotating portion, a second rotating portion, a third rotating portion, and a fourth rotating portion arranged in this order on a velocity diagram, wherein the input element is connectable to the first rotating portion and connectable to the second rotating portion, the output element is connected to the third rotating portion, and the fourth rotating portion is switchable between a rotating state and a non-rotating state, the gear train comprising: a first planetary gear mechanism comprising a first rotating element, a second rotating element, and a third rotating element, wherein the second rotating element is disposed between the first and third rotating elements on the velocity diagram; and a second planetary gear mechanism comprising a fourth rotating element, a fifth rotating element, and a sixth rotating element, wherein the fifth rotating element is disposed between the fourth and sixth rotating elements on the velocity diagram, wherein the first rotating portion is constituted by the third rotating element, the second rotating portion is constituted by the second rotating element and the sixth rotating element being coupled together, and the third rotating portion is constituted by the fifth rotating element, The fourth rotating portion is configured by combining the first rotating element and the fourth rotating element.

[0009] According to the above aspect, three gear stages can be achieved by switching the connection destination of the input element (either one or both of the first and second rotating parts) and the rotation state of the fourth rotating part. Since the inter-stage ratio is small, an appropriate gear ratio can be set depending on the speed range. Furthermore, since the gear ratio is 1 in third gear, power transmission loss due to differential rotation between the rotating parts can be reduced.

[0010] FIG. 1 is a skeleton diagram of a unit according to an embodiment of the present invention. FIG. 2 is an engagement table showing the engagement state of each engagement element at each gear position. FIG. 3 is a speed diagram of the unit. FIG. 4 is a skeleton diagram of a modified example. FIG. 5 is a skeleton diagram of another modified example. FIG. 6A is a skeleton diagram of yet another modified example. FIG. 6B is a speed diagram of the modified example shown in FIG. 6A. FIG. 7A is a skeleton diagram of yet another modified example. FIG. 7B is a speed diagram of the modified example shown in FIG. 7A.

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. The definitions of terms used in this specification are as follows.

[0012] "Unit" refers to a device in general that has a power transmission mechanism such as a gear mechanism or a differential gear mechanism inside, and includes a motor unit having a motor and a power transmission mechanism, an automatic transmission unit, a reducer unit, etc.

[0013] The "gear ratio" is the value obtained by dividing the input rotation speed of a unit by the output rotation speed. "Input rotation" includes not only the rotation input to the unit from a power source outside the unit, but also the rotation input to the unit from a power source inside the unit.

[0014] The "gear ratio" is the value obtained by dividing the larger (low speed) gear ratio by the smaller (high speed) gear ratio of the two gear ratios realized by the unit.

[0015] "Axial direction" refers to the axial direction of the rotating shaft of the parts that make up the unit. The parts are motors, gear mechanisms, differential gear mechanisms, etc. "Radial direction" refers to the radial direction from the central axis of the rotating shaft.

[0016] "Housing" refers to a container that houses the motor, inverter, and power transmission mechanism, and is composed of one or more cases. An embodiment in which the case that houses the motor, the case that houses the inverter, and the case that houses the power transmission mechanism are integrally formed is called "3-in-1."

[0017] The term "motor" refers to a rotating electric machine having a motor function, and may have a generator function in addition to the motor function.

[0018] "Element A is connected to element B" means that element A is connected to element B upstream or downstream in a manner that allows power transmission between element A and element B. The power input side is upstream, and the power output side is downstream. Element A is not limited to being connected to element B directly or via another member, and may be connected via a clutch or the like.

[0019] "Element A is connected to element B" means that element A and element B are connected directly or indirectly via another member, and that element A and element B are integrated. In other words, it can also be said that element A and element B rotate together. It also means that element A and element B are connected without a brake or clutch, and can also be said to be a state in which element A and element B are always connected.

[0020] "Element A is fixed to element B" includes both a case where element A is directly fixed to element B and a case where element A is fixed to element B via an element C other than elements A and B. "Element A is fixed" means a state where element A is fixed to another element and cannot rotate.

[0021] "Element A and element B overlap when viewed in a predetermined direction" refers to a state in which element A and element B are aligned in a predetermined direction (axial direction, radial direction, gravity direction, etc.) and at least partially overlap when observed from the predetermined direction. This is synonymous with "element A and element B overlap in a predetermined direction." When element A and element B overlap when viewed in the axial direction, element A and element B are coaxial. When element A and element B are drawn aligned in a predetermined direction in a drawing, this means that element A and element B overlap when viewed in the predetermined direction.

[0022] In contrast, "element A and element B do not overlap when viewed in a predetermined direction" refers to a state in which element A and element B are not aligned in a predetermined direction (axial direction, radial direction, gravity direction, vehicle running direction, etc.), and there is no overlapping portion between element A and element B when observed from the predetermined direction. This is synonymous with "element A and element B do not overlap in a predetermined direction." When element A and element B are depicted in a drawing so as not to be aligned in a predetermined direction, this means that element A and element B do not overlap when viewed in the predetermined direction.

[0023] "Element A is disposed between element B and element C when viewed in a predetermined direction" means that element A is observed to be between element B and element C when viewed from a predetermined direction (axial direction, radial direction, gravity direction, etc.). For example, when elements B, A, and C are lined up in this order along the axial direction, element A is observed to be between element B and element C when viewed in the radial direction, and therefore element A can be said to be located between element B and element C. Element A does not need to overlap with elements B and C when viewed in the axial direction. When element A is depicted between element B and element C in a drawing, this means that element A is located between element B and element C when viewed in the predetermined direction.

[0024] "Element A is arranged axially outside element B" means that element A is arranged on one axial side or the other axial side of element B, and includes not only the case where element A and element B overlap when viewed in the axial direction, but also the case where element A and element B are not overlapped because their radial positions are different.

[0025] "Element A is positioned radially outside (or radially inside) element B" means that the radial position of element A is outside (or inside) the radial position of element B, and includes not only the case where element A and element B overlap when viewed radially, but also the case where element A and element B are positioned differently in the axial direction and therefore do not overlap.

[0026] "Disposed in close proximity" means that two elements have an overlapping portion when viewed in the axial direction or the radial direction, and no other element is sandwiched between the two elements. For example, "two engaging elements are disposed in close proximity" means that a planetary gear mechanism or the like is not disposed between the two engaging elements. If no other element is depicted between element A and element B in the drawing, this means that element A and element B are disposed in close proximity.

[0027] "One side of the engaging element" and "the other side of the engaging element" refer to two elements included in the engaging element that are unable to rotate relative to each other when the engaging element is in an engaged state and are able to rotate relative to each other when the engaging element is in a released state. "One side of the engaging element" and "the other side of the engaging element" may be a combination of rotating elements, or a combination of a rotating element and a non-rotating element; the former is generally called a clutch and the latter is generally called a brake. Also, "one side of the engaging element" means either "one side of the engaging element" or "the other side of the engaging element."

[0028] Other terms will be defined as appropriate throughout the specification.

[0029] FIG. 1 is a skeleton diagram showing the basic structure of a unit 100 according to an embodiment of the present invention. The unit 100 is a three-speed forward automatic transmission unit for an electric vehicle that changes the speed of rotation input to an input element IN from a motor (not shown) as a power source at a gear ratio corresponding to the gear position and transmits the rotation from an output element OUT to drive wheels (not shown). The input element IN and output element OUT are each composed of gears, a rotating shaft, etc. Because the motor can be switched between forward and reverse rotation, the unit 100 does not have a reverse gear, which clearly differentiates the design concept from units for vehicles that use an internal combustion engine as a power source.

[0030] The unit 100 is a so-called 3-in-1 unit that houses an input element IN, a gear device 2, first to third engagement elements CL1, CL2, and B1, an output element OUT, and a motor and inverter (not shown) within a housing 1. The housing 1 is fixed to the vehicle so as not to be rotatable.

[0031] One end of the input element IN is connected to the output shaft of the motor, and the input element IN rotates by the power input from the motor. The rotational speed of the input element IN is the input rotational speed of the unit 100. The motor is electrically connected to a battery (not shown) outside the unit 100 via an inverter, and receives power from the battery to function as an electric motor. The motor can also function as a generator.

[0032] The gear device 2 is configured by arranging a first planetary gear mechanism PG1 and a second planetary gear mechanism PG2 close to each other and coupling their rotational elements together at two locations.

[0033] The first planetary gear mechanism PG1 is a single-pinion planetary gear mechanism having a first sun gear S1 as a first rotating element, a plurality of first pinion gears (not shown), a first carrier C1 as a second rotating element that rotatably supports the plurality of first pinion gears, and a first ring gear R1 as a third rotating element. The first sun gear S1 meshes with the plurality of first pinion gears, and the plurality of first pinion gears mesh with the first ring gear R1.

[0034] The second planetary gear mechanism PG2 is a single-pinion planetary gear mechanism including a second sun gear S2 as a fourth rotating element, a plurality of second pinion gears (not shown), a second carrier C2 as a fifth rotating element that rotatably supports the plurality of second pinion gears, and a second ring gear R2 as a sixth rotating element. The second sun gear S2 meshes with the plurality of second pinion gears, and the plurality of second pinion gears mesh with the second ring gear R2.

[0035] In the drawings, the "S" in parentheses next to the reference symbols PG1 and PG2 indicates that the planetary gear mechanism is a single-pinion planetary gear mechanism. Although not mentioned in this embodiment, if the planetary gear mechanism is a double-pinion planetary gear mechanism, a "D" in parentheses is placed next to PG1 and PG2.

[0036] The first sun gear S1 is coupled to the second sun gear S2. The first carrier C1 is coupled to the second ring gear R2. By coupling the first planetary gear mechanism PG1 and the second planetary gear mechanism PG2 at two locations in this manner, a first rotational part P1 is formed by the first ring gear R1, a second rotational part P2 is formed by the first carrier C1 and the second ring gear R2, a third rotational part P3 is formed by the second carrier C2, and a fourth rotational part P4 is formed by the first sun gear S1 and the second sun gear S2.

[0037] The rotational speed of the output element OUT is the output rotational speed of the unit 100 .

[0038] The first engagement element CL1 is a hydraulic or electric clutch. If we define two portions of the first engagement element CL1 that are engaged when the first engagement element CL1 is in an engaged state as one side and the other side, one side is connected to the input element IN, and the other side is connected to a second rotational portion P2 that is made up of the first carrier C1 and the second ring gear R2. As a result, when the first engagement element CL1 is engaged, the input element IN can be connected to the second rotational portion P2 that is made up of the first carrier C1 and the second ring gear R2.

[0039] The second engagement element CL2 is a hydraulic or electric clutch. The two portions of the second engagement element CL2 that are engaged when the second engagement element CL2 is engaged are referred to as one side and the other side. One side is connected to the input element IN, and the other side is connected to the first rotational portion P1 that is formed by the first ring gear R1. Therefore, when the second engagement element CL2 is engaged, the input element IN can be connected to the first rotational portion P1 that is formed by the first ring gear R1.

[0040] Because one side of the first engaging element CL1 and one side of the second engaging element CL2 are both connected to the input element IN and rotate integrally, they can be shared, i.e., configured as an integrated part. For example, if the first engaging element CL1 and the second engaging element CL2 are each configured as a multi-plate clutch in which multiple friction plates are arranged between a drum and a hub, they can be configured as an integrated part by forming the hub of one drum on the outer periphery of the other drum. This reduces the number of parts in the unit 100.

[0041] The third engagement element B1 is a hydraulic or electric brake. If the two portions of the third engagement element B1 that are engaged when the third engagement element B1 is in an engaged state are referred to as one side and the other side, one side is connected to a fourth rotational portion P4 that is made up of the first sun gear S1 and the second sun gear S2, and the other side is fixed to the housing 1. As a result, when the third engagement element B1 is engaged, the fourth rotational portion P4 that is made up of the first sun gear S1 and the second sun gear S2 can be fixed to the housing 1.

[0042] As the actuator for the second engaging element CL2, it is possible to use an actuator that is less subject to layout constraints (such as a hydraulic actuator that supplies hydraulic pressure from a control valve unit), as well as an actuator that is more subject to layout constraints (such as an electric actuator that needs to be fixed to the housing 1 or the like and connected to a power cable due to reaction forces, or a hydraulic actuator that needs to have a hydraulic supply unit attached to the housing 1 or the like and connected to the hydraulic supply unit via piping). On the other hand, as the actuators for the first engaging element CL1 and the third engaging element B1, it is preferable to use actuators that are less subject to layout constraints, because the first engaging element CL1 and the third engaging element B1 are disposed on the inner periphery of the second engaging element CL2.

[0043] The third engagement element B1 may be configured as a selectable one-way clutch. The selectable one-way clutch is a clutch whose operating state can be switched by an electric actuator, and which is configured as a pair of ratchet mechanisms that restrict rotation in different directions. When only one of the pair of ratchet mechanisms is operated, the clutch enters a one-way clutch state, and when both of the pair of ratchet mechanisms are operated, the clutch enters an engaged state.

[0044] By providing these first to third engagement elements CL1, CL2, and B1, the input element IN can be selectively connected to the first rotational part P1 consisting of the first ring gear R1 or the second rotational part P2 consisting of the first carrier C1 and the second ring gear R2 by engaging one of the first engagement element CL1 and the second engagement element CL2 and disengaging the other. Furthermore, by engaging both the first engagement element CL1 and the second engagement element CL2, the input element IN can be connected to the first rotational part P1 and the second rotational part P2.

[0045] Furthermore, by changing the engagement state of the third engagement element B1, the fourth rotational part P4 made up of the first sun gear S1 and the second sun gear S2 can be switched between a rotating state and a non-rotating state.

[0046] Furthermore, when viewed in the radial direction, the first to third engaging elements CL1, CL2, B1 are arranged axially outward of the gear device 2. Because no engaging elements are arranged between the first planetary gear mechanism PG1 and the second planetary gear mechanism PG2, the degree of freedom in layout of the first to third engaging elements CL1, CL2, B1 increases, and the axial dimension of the unit 100 can be reduced.

[0047] Furthermore, since the first to third engaging elements CL1, CL2, B1 are arranged together on one axial side of the gear device 2, the axial dimension of the unit 100 can be further reduced.

[0048] Furthermore, when viewed in the axial direction, the first to third engaging elements CL1, CL2, B1 can be made to overlap with the gear device 2. When these are made to overlap, the radial dimension of the unit 100 can be reduced.

[0049] 2 is an engagement table showing the relationship between the engagement states of the first to third engagement elements CL1, CL2, and B1 and the gear positions achieved in the unit 100. In the table, black circles indicate engaged states, and no circles indicate disengaged states.

[0050] As shown in the engagement table, first gear is achieved by engaging the second engagement element CL2 and the third engagement element B1 and disengaging the first engagement element CL1. Second gear is achieved by engaging the first engagement element CL1 and the third engagement element B1 and disengaging the second engagement element CL2. Third gear is achieved by engaging the first engagement element CL1 and the second engagement element CL2 and disengaging the third engagement element B1.

[0051] Each gear is achieved by engaging two of the first to third engaging elements CL1, CL2, and B1, and only one engaging element is disengaged. In cases where the disengaged engaging elements are in contact with each other and generate drag torque even when in a disengaged state, such as with a multi-plate clutch, the fewer engaging elements that are disengaged to achieve the gear, the more mechanical loss can be reduced. In this embodiment, because only one engaging element is disengaged in each gear, even when engaging elements that generate drag torque are used as the first to third engaging elements CL1, CL2, and B1, mechanical loss can be reduced, and the electric fuel efficiency of the vehicle in which the unit 100 is installed can be improved.

[0052] 3 is a velocity diagram of the unit 100. On the velocity diagram, first to fourth rotational regions P1 to P4 are arranged in this order, and vertical lines 11 to 14 correspond to the respective rotational regions.

[0053] The first planetary gear mechanism PG1 is a single-pinion planetary gear mechanism, and therefore the first carrier C1 is disposed between the first sun gear S1 and the first ring gear R1. The second planetary gear mechanism PG2 is also a single-pinion planetary gear mechanism, and therefore the second carrier C2 is disposed between the second sun gear S2 and the second ring gear R2.

[0054] When the first engagement element CL1 is engaged and the second engagement element CL2 is disengaged, the input element IN is connected to the second rotational position P2, and therefore the vertical line l2 corresponds to the input element IN. Conversely, when the first engagement element CL1 is disengaged and the second engagement element CL2 is engaged, the input element IN is connected to the first rotational position P1, and therefore the vertical line l1 corresponds to the input element IN.

[0055] The output element OUT is connected to the third rotation part P3, so that the vertical line l3 corresponds to the output element OUT.

[0056] When the distance between vertical line l4 and vertical line l2 is 1, the distance α1 between vertical line l2 and vertical line l1 is the value obtained by dividing the number of teeth of the first sun gear S1 by the number of teeth of the first ring gear R1. When the distance between vertical line l4 and vertical line l3 is 1, the distance α2 between vertical line l3 and vertical line l2 is the value obtained by dividing the number of teeth of the second sun gear S2 by the number of teeth of the second ring gear R2.

[0057] The speed diagram depicts straight lines L1 to L3 corresponding to each gear. The rotational speed of each rotational portion P1 to P4 at each gear is represented by the ordinate of the intersection of the straight lines L1 to L3 corresponding to each gear and the vertical lines 11 to 14.

[0058] In first gear, the second engaging element CL2 and the third engaging element B1 are engaged, and the first engaging element CL1 is disengaged. As a result, the rotational speeds of the input element IN and the first rotational part P1 are equal, and the rotational speed of the fourth rotational part P4 is zero, so that the line L1 corresponding to first gear is a line passing through points X3 and X2. The rotational speed of the output element OUT is r1, which is the ordinate of the intersection of line L1 and vertical line l3. Therefore, the gear ratio in first gear is rin / r1, where rin is the rotational speed of the input element IN.

[0059] In second gear, the first engaging element CL1 and the third engaging element B1 are engaged, and the second engaging element CL2 is disengaged. As a result, the rotational speeds of the input element IN and the second rotational part P2 are equal, and the rotational speed of the fourth rotational part P4 is zero. Therefore, the line L2 corresponding to second gear passes through points X1 and X2 and has a steeper slope than line L1. The rotational speed of the output element OUT is r2, which is the ordinate of the intersection of line L2 and vertical line l3. Therefore, the gear ratio in second gear is rin / r2, where rin is the rotational speed of the input element IN. Because r2 is greater than r1, the gear ratio in second gear is smaller than the gear ratio in first gear.

[0060] In third gear, the first engaging element CL1 and the second engaging element CL2 are engaged, and the third engaging element B1 is disengaged. As a result, the rotational speeds of the input element IN, the first to fourth rotational portions P1 to P4, and the output element OUT are equal, so the line L3 corresponding to third gear is a line that passes through points X3 and X1 and has a slope of zero. Because the rotational speeds of the input element IN and the output element OUT are equal, the gear ratio in third gear is 1, which is smaller than the gear ratios of first and second gears.

[0061] Therefore, in unit 100, three gears can be realized, so the inter-speed ratio is smaller than in a unit with two forward speeds, and shock during gear changes can be kept smaller than in a unit with two forward speeds. Also, since first to third speeds can be used for low, medium, and high speeds, respectively, an appropriate gear ratio can be set according to the speed range.

[0062] In addition, the gear ratio is 1 in third gear. In other words, all of the rotating parts P1 to P4 that make up the gear device 2 rotate at the same rotational speed, which reduces power transmission loss caused by differential rotation between the rotating parts. Because third gear is used frequently for high-speed cruising, achieving a gear ratio of 1 in third gear can significantly improve electricity consumption.

[0063] Next, a modified example of the embodiment of the present invention will be described.

[0064] Fig. 4 is a skeleton diagram of a unit 100 according to a modified example. This differs from the skeleton diagram shown in Fig. 1 in that one side of the first engagement element CL1 is connected to the input element IN via a first connecting member M1 that passes through the inner periphery of the gear device 2, and the other side is connected to a second rotation part P2 that is made up of the first carrier C1 and the second ring gear R2 via a second connecting member M2 that passes through the inner periphery of the gear device 2.

[0065] The engagement table and speed diagram are the same as those shown in FIGS.

[0066] 4, it is possible to adopt a layout in which the first engaging element CL1 and the second engaging element CL2 are disposed dispersedly on both axial sides of the gear device 2, and the first engaging element CL1 and the third engaging element B1 are not disposed on the inner peripheral side of the second engaging element CL2. This makes it easier to adopt actuators that are subject to layout constraints as actuators for the first to third engaging elements CL1, CL2, and B1, and improves the degree of freedom in selecting the actuators to be used for the first to third engaging elements CL1, CL2, and B1.

[0067] 5 is a skeleton diagram of a unit 100 according to another modified example. The first planetary gear mechanism PG1 and the second planetary gear mechanism PG2 are single-pinion planetary gear mechanisms, similar to the unit 100 shown in FIG.

[0068] In this unit 100, the first rotating part P1 is constituted by the first ring gear R1, the second rotating part P2 is constituted by the first carrier C1 and the second ring gear R2 connected together, the third rotating part P3 is constituted by the second carrier C2, and the fourth rotating part P4 is constituted by the first sun gear S1 and the second sun gear S2 connected together.

[0069] One side of the first engaging element CL1 is connected to the input element IN via a first connecting member M1 that passes through the inner side of the gear device 2, and the other side of the first engaging element CL1 is connected to the first carrier C1 and second ring gear R2 as the second rotational portion P2 via a second connecting member M2 that passes through the inner side of the gear device 2, one side of the second engaging element CL2 is connected to the input element IN, and the other side of the second engaging element CL2 is connected to the first ring gear R1 as the first rotational portion P1, one side of the third engaging element B1 is connected to the first sun gear S1 and second sun gear S2 as the fourth rotational portion P4, and the other side of the third engaging element B1 is fixed to the housing 1.

[0070] 5, the first engaging element CL1 and the second engaging element CL2 are disposed on both axial sides of the gear device 2, and a layout can be adopted in which the first engaging element CL1 and the third engaging element B1 are not disposed on the inner circumferential side of the second engaging element CL2. This makes it easier to use actuators that are subject to layout restrictions as actuators for the first to third engaging elements CL1, CL2, and B1, and improves the degree of freedom in selecting the actuators to be used for the first to third engaging elements CL1, CL2, and B1. The third engaging element B1 may be configured as a selectable one-way clutch.

[0071] Furthermore, since the first to third engaging elements CL1, CL2, and B1 are each positioned axially outside the gear device 2, the layout freedom of the first to third engaging elements CL1, CL2, and B1 is increased, and the axial dimension of the unit 100 can be reduced.

[0072] Furthermore, when viewed in the axial direction, the first to third engaging elements CL1, CL2, B1 can be made to overlap with the gear device 2. When these are made to overlap, the radial dimension of the unit 100 can be reduced.

[0073] Furthermore, one side of the first engaging element CL1 and one side of the second engaging element CL2 can be made into a common component (integrated component), thereby reducing the number of components of the unit 100.

[0074] The engagement table is the same as that shown in Figure 2, and three gear stages can be achieved by changing two of the first to third engagement elements CL1, CL2, and B1 that are engaged. Because the inter-stage ratio is small, an appropriate gear ratio can be set depending on the speed range. In addition, because the gear ratio is 1 in third gear, power transmission loss due to differential rotation between rotating parts can be reduced.

[0075] Since only one engagement element is released in any gear position, even when engagement elements that generate drag torque are used as the first to third engagement elements CL1, CL2, B1, mechanical loss can be suppressed and the electric fuel economy of the vehicle in which the unit 100 is installed can be improved.

[0076] The velocity diagram is the same as that shown in FIG.

[0077] Figure 6A is a skeleton diagram of a unit 100 according to yet another modification. Unlike the unit 100 shown in Figure 1, the first planetary gear mechanism PG1 is a double-pinion planetary gear mechanism. That is, the first carrier C1 rotatably supports a plurality of inner pinion gears (not shown) that mesh with the first sun gear S1 and a plurality of outer pinion gears (not shown) that mesh with the first ring gear R1, and the plurality of inner pinion gears mesh with a plurality of outer pinion gears. The second planetary gear mechanism PG2 is a single-pinion planetary gear mechanism, like the unit 100 shown in Figure 1.

[0078] In this unit 100, the first rotating part P1 is formed by the first carrier C1, the second rotating part P2 is formed by connecting the first ring gear R1 and the second ring gear R2, the third rotating part P3 is formed by the second carrier C2, and the fourth rotating part P4 is formed by connecting the first sun gear S1 and the second sun gear S2.

[0079] One side of the first engaging element CL1 is connected to the input element IN, the other side of the first engaging element CL1 is connected to the first ring gear R1 and second ring gear R2 as the second rotational portion P2, one side of the second engaging element CL2 is connected to the input element IN, the other side of the second engaging element CL2 is connected to the first carrier C1 as the first rotational portion P1, one side of the third engaging element B1 is connected to the first sun gear S1 and second sun gear S2 as the fourth rotational portion P4, and the other side of the third engaging element B1 is fixed to the housing 1.

[0080] According to the modified example shown in FIG. 6A, the first to third engaging elements CL1, CL2, B1 are each arranged axially outside the gear device 2, which increases the degree of freedom in layout of the first to third engaging elements CL1, CL2, B1 and also enables the axial dimension of the unit 100 to be reduced.

[0081] Furthermore, when viewed in the axial direction, the first to third engaging elements CL1, CL2, B1 can be made to overlap with the gear device 2. When these are made to overlap, the radial dimension of the unit 100 can be reduced.

[0082] Furthermore, one side of the first engaging element CL1 and one side of the second engaging element CL2 can be made into a common component (integrated component), thereby reducing the number of components of the unit 100.

[0083] The engagement table is the same as that shown in Figure 2, and three gear stages can be achieved by changing two of the first to third engagement elements CL1, CL2, and B1 that are engaged. Because the inter-stage ratio is small, an appropriate gear ratio can be set depending on the speed range. In addition, because the gear ratio is 1 in third gear, power transmission loss due to differential rotation between rotating parts can be reduced.

[0084] Since only one engagement element is released in any gear position, even when engagement elements that generate drag torque are used as the first to third engagement elements CL1, CL2, B1, mechanical loss can be suppressed and the electric fuel economy of the vehicle in which the unit 100 is installed can be improved.

[0085] Figure 6B is a velocity diagram of the modified example shown in Figure 6A. Because the first planetary gear mechanism PG1 is a double-pinion planetary gear mechanism, the first ring gear R1 is disposed between the first sun gear S1 and the first carrier C1 on the velocity diagram. In other words, the second and third rotating elements are reversed from those in the case of a single-pinion planetary gear mechanism.

[0086] The rotational elements that make up the first to fourth rotational regions P1 to P4 and the spacing between the vertical lines l1 to l4 are different from those shown in FIG. 3, but the connection relationships between the first to fourth rotational regions P1 to P4 and the first to third engagement elements CL1, CL2, and B1 are the same, so that substantially the same velocity diagram is obtained.

[0087] 7A is a skeleton diagram of a unit 100 according to yet another modification. Unlike the unit 100 shown in FIG. 1, the second planetary gear mechanism PG2 is a double-pinion planetary gear mechanism. That is, the second carrier C2 rotatably supports a plurality of inner pinion gears (not shown) that mesh with the second sun gear S2 and a plurality of outer pinion gears (not shown) that mesh with the second ring gear R2, and the plurality of inner pinion gears mesh with the plurality of outer pinion gears. The first planetary gear mechanism PG1 is a single-pinion planetary gear mechanism, like the unit 100 shown in FIG. 1.

[0088] In this unit 100, the first rotating part P1 is constituted by the first ring gear R1, the second rotating part P2 is constituted by connecting the first carrier C1 and the second carrier C2, the third rotating part P3 is constituted by the second ring gear R2, and the fourth rotating part P4 is constituted by connecting the first sun gear S1 and the second sun gear S2.

[0089] One side of the first engaging element CL1 is connected to the input element IN, the other side of the first engaging element CL1 is connected to the first carrier C1 and the second carrier C2 as the second rotational portion P2, one side of the second engaging element CL2 is connected to the input element IN, the other side of the second engaging element CL2 is connected to the first ring gear R1 as the first rotational portion P1, one side of the third engaging element B1 is connected to the first sun gear S1 and the second sun gear S2 as the fourth rotational portion P4, and the other side of the third engaging element B1 is fixed to the housing 1.

[0090] According to the modified example shown in FIG. 7A, the first to third engaging elements CL1, CL2, B1 are each positioned axially outside the gear device 2, which increases the layout freedom of the first to third engaging elements CL1, CL2, B1 and also enables the axial dimension of the unit 100 to be reduced.

[0091] Furthermore, when viewed in the axial direction, the first to third engaging elements CL1, CL2, B1 can be made to overlap with the gear device 2. When these are made to overlap, the radial dimension of the unit 100 can be reduced.

[0092] Furthermore, one side of the first engaging element CL1 and one side of the second engaging element CL2 can be made into a common component (integrated component), thereby reducing the number of components of the unit 100.

[0093] The engagement table is the same as that shown in Figure 2, and three gear stages can be achieved by changing two of the first to third engagement elements CL1, CL2, and B1 that are engaged. Because the inter-stage ratio is small, an appropriate gear ratio can be set depending on the speed range. In addition, because the gear ratio is 1 in third gear, power transmission loss due to differential rotation between rotating parts can be reduced.

[0094] Since only one engagement element is released in any gear position, even when engagement elements that generate drag torque are used as the first to third engagement elements CL1, CL2, B1, mechanical loss can be suppressed and the electric fuel economy of the vehicle in which the unit 100 is installed can be improved.

[0095] Figure 7B is a velocity diagram of the modified example shown in Figure 7A. Because the second planetary gear mechanism PG2 is a double-pinion planetary gear mechanism, the second ring gear R2 is disposed between the second sun gear S2 and the second carrier C2 on the velocity diagram. In other words, the second and third rotating elements are reversed from those in the case of a single-pinion planetary gear mechanism.

[0096] The rotational elements that make up the first to fourth rotational regions P1 to P4 and the spacing between the vertical lines l1 to l4 are different from those shown in FIG. 3, but the connection relationships between the first to fourth rotational regions P1 to P4 and the first to third engagement elements CL1, CL2, and B1 are the same, so that substantially the same velocity diagram is obtained.

[0097] Next, the effects of the embodiment of the present invention will be described.

[0098] 1, 4, and 5, the unit 100 includes an input element IN, an output element OUT, and a gear device 2 (FIG. 3) having a first rotating part P1, a second rotating part P2, a third rotating part P3, and a fourth rotating part P4 arranged in this order on a velocity diagram. The input element IN is connectable to the first rotating part P1 and also to the second rotating part P2, the output element OUT is connected to the third rotating part P3, and the fourth rotating part P4 is switchable between a rotating state and a non-rotating state. The gear device 2 includes a first single-pinion planetary gear mechanism PG1 ( FIG. 3 ) including a first sun gear S1, a first carrier C1, and a first ring gear R1, with the first carrier C1 disposed between the first sun gear S1 and the first ring gear R1 on a velocity diagram, and a second single-pinion planetary gear mechanism PG2 ( FIG. 3 ) including a second sun gear S2, a second carrier C2, and a second ring gear R2, with the second carrier C2 disposed between the second sun gear S2 and the second ring gear R2 on a velocity diagram. The first rotational portion P1 is formed by the first ring gear R1, the second rotational portion P2 is formed by the first carrier C1 and the second ring gear R2 being coupled together, the third rotational portion P3 is formed by the second carrier C2, and the fourth rotational portion P4 is formed by the first sun gear S1 and the second sun gear S2 being coupled together.

[0099] 6A , the unit 100 includes an input element IN, an output element OUT, and a gear device 2 ( FIG. 6B ) having a first rotating part P1, a second rotating part P2, a third rotating part P3, and a fourth rotating part P4 arranged in this order on a velocity diagram. The input element IN is connectable to the first rotating part P1 and also to the second rotating part P2, the output element OUT is connected to the third rotating part P3, and the fourth rotating part P4 is switchable between a rotating state and a non-rotating state. The gear device 2 includes a double-pinion first planetary gear mechanism PG1 ( FIG. 6B ) including a first sun gear S1, a first ring gear R1, and a first carrier C1, with the first ring gear R1 disposed between the first sun gear S1 and the first carrier C1 on a velocity diagram, and a single-pinion second planetary gear mechanism PG2 ( FIG. 6B ) including a second sun gear S2, a second carrier C2, and a second ring gear R2, with the second carrier C2 disposed between the second sun gear S2 and the second ring gear R2 on a velocity diagram. The first rotation portion P1 is formed by the first carrier C1, the second rotation portion P2 is formed by the first ring gear R1 and the second ring gear R2 being coupled together, the third rotation portion P3 is formed by the second carrier C2, and the fourth rotation portion P4 is formed by the first sun gear S1 and the second sun gear S2 being coupled together.

[0100] 7A , the unit 100 includes an input element IN, an output element OUT, and a gear device 2 ( FIG. 7B ) having a first rotating portion P1, a second rotating portion P2, a third rotating portion P3, and a fourth rotating portion P4 arranged in this order on a velocity diagram. The input element IN is connectable to the first rotating portion P1 and also to the second rotating portion P2, the output element OUT is connected to the third rotating portion P3, and the fourth rotating portion P4 is switchable between a rotating state and a non-rotating state. The gear device 2 includes: a single-pinion first planetary gear mechanism PG1 ( FIG. 7B ) including a first sun gear S1, a first ring gear R1, and a first carrier C1, with the first carrier C1 disposed between the first sun gear S1 and the first ring gear R1 on a speed diagram; and a double-pinion second planetary gear mechanism PG2 ( FIG. 7B ) including a second sun gear S2, a second carrier C2, and a second ring gear R2, with the second ring gear R2 disposed between the second sun gear S2 and the second carrier C2 on a speed diagram. The first rotation portion P1 is formed by the first ring gear R1, the second rotation portion P2 is formed by the first carrier C1 and the second carrier C2 being coupled together, the third rotation portion P3 is formed by the second ring gear R2, and the fourth rotation portion P4 is formed by the first sun gear S1 and the second sun gear S2 being coupled together.

[0101] 1, 4, 5, 6A, and 7A, three gear stages can be achieved by switching the connection destination of the input element IN (either or both of the first rotating part P1 and the second rotating part P2) and the rotation state of the fourth rotating part P4. Because the inter-stage ratio is small, an appropriate gear ratio can be set according to the speed range. Furthermore, because the gear ratio is 1 in third gear, power transmission loss due to differential rotation between the rotating parts can be reduced.

[0102] (2) The connection destination of the input element IN and the rotation state of the fourth rotation part P4 can be switched by the first to third engagement elements CL1, CL2, and B1.

[0103] In the examples shown in Figures 1, 4, 5, 6A, and 7A, the unit 100 comprises a first engagement element CL1, a second engagement element CL2, and a third engagement element B1, one side of the first engagement element CL1 is connected to the input element IN, the other side of the first engagement element CL1 is connected to the second rotation portion P2, one side of the second engagement element CL2 is connected to the input element IN, the other side of the second engagement element CL2 is connected to the first rotation portion P1, one side of the third engagement element B1 is connected to the fourth rotation portion P4, and the other side of the third engagement element B1 is fixed.

[0104] According to this configuration, when viewed in the axial direction, the first to third engaging elements CL1, CL2, B1 can be made to overlap with the gear device 2. When these are made to overlap, the radial dimension of the unit 100 can be reduced.

[0105] 1, 4, 5, 6A, and 7A, the first to third engaging elements CL1, CL2, and B1 are each disposed axially outward of the gear device 2. This increases the degree of freedom in the layout of the first to third engaging elements CL1, CL2, and B1, and also enables the axial dimension of the unit 100 to be reduced.

[0106] 4 and 5 , one side of the first engaging element CL1 is connected to the input element IN via a first connecting member M1 that passes through the inner circumferential side of the gear device 2, and the other side of the first engaging element CL1 is connected to the second rotation part P2 via a second connecting member M2 that passes through the inner circumferential side of the gear device 2. As a result, the first engaging element CL1 and the second engaging element CL2 are disposed dispersedly on both axial sides of the gear device 2, and a layout can be adopted in which the first engaging element CL1 and the third engaging element B1 are not disposed on the inner circumferential side of the second engaging element CL2. This makes it easier to employ actuators that are subject to layout constraints as actuators for the first to third engaging elements CL1, CL2, and B1, thereby improving the freedom of actuator selection.

[0107] (5) In the examples shown in Figures 1, 4, 5, 6A, and 7A, three gear positions are achieved by changing two of the first to third engaging elements CL1, CL2, and B1 that are engaged (Figure 2). Because one engaging element is disengaged in each gear position, even when engaging elements that generate drag torque are used as the first to third engaging elements CL1, CL2, and B1, mechanical loss can be reduced, and the electric fuel economy of the vehicle in which the unit 100 is installed can be improved.

[0108] 1, 4, 5, 6A, and 7A, one side of the first engaging element CL1 and one side of the second engaging element CL2 may be formed as an integrated part. This reduces the number of parts in the unit 100.

[0109] Although the embodiments of the present invention have been described above, the above embodiments are merely application examples of the present invention, and the technical scope of the present invention is not intended to be limited to the specific configurations of the above embodiments.

[0110] The skeleton diagrams shown in FIGS. 1, 4, 5, 6A, and 7A are only some of the application examples of the present invention, and the skeleton diagrams of units to which the present invention is applied are not limited to these.

[0111] Furthermore, either a single-pinion planetary gear mechanism or a double-pinion planetary gear mechanism may be used as the first planetary gear mechanism PG1 and the second planetary gear mechanism PG2.

[0112] 1: Housing 2: Gear device 100: Unit CL1: First engaging element CL2: Second engaging element B1: Third engaging element S1: First sun gear S2: Second sun gear C1: First carrier C2: Second carrier R1: First ring gear R2: Second ring gear M1: Connecting member M2: Connecting member P1: First rotating part P2: Second rotating part P3: Third rotating part P4: Fourth rotating part IN: Input element OUT: Output element PG1: First planetary gear mechanism PG2: Second planetary gear mechanism

Claims

1. An input element; An output element; a gear device in which a first rotation region, a second rotation region, a third rotation region, and a fourth rotation region are arranged in this order on a speed diagram; Equipped with the input element is connectable to the first rotation portion and connectable to the second rotation portion; the output element is connected to the third rotation portion; The fourth rotating portion is switchable between a rotating state and a non-rotating state, The gear device comprises: a first planetary gear mechanism including a first rotating element, a second rotating element, and a third rotating element, the second rotating element being disposed between the first rotating element and the third rotating element on a speed diagram; a second planetary gear mechanism including a fourth rotating element, a fifth rotating element, and a sixth rotating element, the fifth rotating element being disposed between the fourth rotating element and the sixth rotating element on a speed diagram; Equipped with the first rotating portion is composed of the third rotating element, The second rotating portion is configured by combining the second rotating element, which is a first ring gear, and the sixth rotating element, which is a second ring gear, the third rotating portion is composed of the fifth rotating element, The fourth rotating portion is configured by combining the first rotating element, which is a first sun gear, and the fourth rotating element, which is a second sun gear. unit.

2. 2. The unit of claim 1, A first engagement element; A second engagement element; A third engagement element; Equipped with One side of the first engagement element is connected to the input element, The other side of the first engagement element is connected to the second rotation portion, One side of the second engagement element is connected to the input element; The other side of the second engagement element is connected to the first rotation portion, One side of the third engagement element is connected to the fourth rotation portion, The other side of the third engagement element is fixed. unit.

3. 3. The unit according to claim 2, The first to third engagement elements are each disposed axially outward of the gear device. unit.

4. 3. The unit according to claim 2, the one side of the first engagement element is connected to the input element via a first connection member passing through an inner peripheral side of the gear device, The other side of the first engagement element is connected to the second rotation portion via a second connection member passing through an inner peripheral side of the gear device. unit.

5. 3. The unit according to claim 2, Three gear stages are realized by changing two of the first to third engagement elements. unit.

6. 3. The unit according to claim 2, The one side of the first engagement element and the one side of the second engagement element are configured as an integral part. unit.

7. An input element; An output element; a gear device in which a first rotation region, a second rotation region, a third rotation region, and a fourth rotation region are arranged in this order on a speed diagram; Equipped with the input element is connectable to the first rotation portion and connectable to the second rotation portion; the output element is connected to the third rotation portion; The fourth rotating portion is switchable between a rotating state and a non-rotating state, The gear device comprises: a first planetary gear mechanism including a first rotating element, a second rotating element, and a third rotating element, the second rotating element being disposed between the first rotating element and the third rotating element on a speed diagram; a second planetary gear mechanism including a fourth rotating element, a fifth rotating element, and a sixth rotating element, the fifth rotating element being disposed between the fourth rotating element and the sixth rotating element on a speed diagram; Equipped with the first rotating portion is composed of the third rotating element, The second rotating portion is configured by combining the second rotating element, which is a first carrier, and the sixth rotating element, which is a second carrier; the third rotating portion is composed of the fifth rotating element, The fourth rotating portion is a unit formed by coupling the first rotating element, which is a first sun gear, and the fourth rotating element, which is a second sun gear.