Clutch hub and two-speed transmission

Abstract

The clutch hub comprises a first engagement portion disposed on one axial side of the outer peripheral surface and engaged with a component constituting a friction clutch device, a second engagement portion disposed on the other axial side of the outer peripheral surface and engaged with a component constituting a device other than the friction clutch device, a cylindrical portion having oil holes radially penetrating multiple locations in the same axial range as the first engagement portion, and a side plate portion extending radially inward from the end portion on one axial side of the cylindrical portion, wherein the cylindrical portion has a damming surface facing one axial side in an axial intermediate portion of its inner peripheral surface located on the other axial side of the oil hole, and the inner diameter of the damming surface is equal to or smaller than the inner diameter of the smallest inner diameter portion of the inner peripheral surface adjacent to the damming surface on one axial side.

Description

[Technical Field]

[0001] The present disclosure relates to a clutch hub and a two-speed transmission equipped with the clutch hub. [Background technology]

[0002] In response to the recent trend toward reducing fossil fuel consumption, research into electric vehicles and hybrid vehicles has progressed, and some have already been implemented. Unlike internal combustion engines (engines) that run on the direct combustion of fossil fuels, electric motors, which are the power source for electric and hybrid vehicles, generally generate maximum torque at startup, and the torque and rotational speed characteristics of the output shaft are favorable for automotive use, so they do not necessarily require a transmission like those used in typical automobiles that use internal combustion engines as their power source. However, even when an electric motor is used as the power source, the addition of a transmission can improve acceleration and high-speed performance. Specifically, the addition of a transmission can smooth the relationship between the vehicle's speed and acceleration, similar to that of an automobile equipped with an internal combustion engine and a transmission in its power transmission system.

[0003] International Publication WO2022 / 074958 discloses a two-speed transmission structure that can switch between a low reduction ratio mode, in which the reduction ratio between the input member and the output member is small, and a high reduction ratio mode, in which the reduction ratio is larger than that in the low reduction ratio mode. This conventional two-speed transmission switches between the low reduction ratio mode and the high reduction ratio mode by switching between the mode of a first engagement device provided between the input member and the rotating member and the mode of a second engagement device provided between a fixed portion and the rotating member.

[0004] The first engagement device is configured as a multi-plate clutch formed by alternately stacking a plurality of first friction plates and a plurality of second friction plates. The second engagement device is configured to be able to switch between a mode in which the inner diameter side cylindrical member and the outer diameter side cylindrical member are rotatable relative to each other and a mode in which they are not rotatable relative to each other by switching the engagement state between the engagement pin and the engagement recess based on the rotation of a selector plate. In a conventional two-stage transmission, the second friction plate is fitted onto a first cylindrical portion of a stepped cylindrical member constituting the rotating member so as to be non-rotatable but displaceable in the axial direction, and the inner diameter side cylindrical member is fitted onto a second cylindrical portion of the stepped cylindrical member so as to be non-rotatable.

[0005] In order to prevent wear, seizure, etc., it is necessary to supply lubricating oil to the area between the first friction plate and the second friction plate that constitute the first engagement device, and to the area between the inner diameter side cylindrical member and the outer diameter side cylindrical member that constitute the second engagement device.

[0006] In the conventional two-speed transmission described in International Publication WO 2022 / 074958, the shaft member constituting the rotating member has a through-hole in the center for circulating lubricating oil. That is, the lubricating oil circulating in the through-hole moves radially outward while lubricating each part of the two-speed transmission. Some of the lubricating oil lubricates the area between the first friction plate and the second friction plate constituting the first engagement device, and the area between the inner diameter side cylindrical member and the outer diameter side cylindrical member constituting the second engagement device.

[0007] Japanese Patent Application Laid-Open Publication No. 2019-168101 discloses a clutch hub structure having an oil hole for sending lubricating oil supplied from the radially inner side to the area between first and second friction plates arranged radially outward. As shown in Figure 21, a clutch hub 200 according to a first example of a conventional structure described in Japanese Patent Application Laid-Open Publication No. 2019-168101 includes a cylindrical tubular portion 201 and a hollow, circular, plate-like side plate 202 that bends radially inward from one axial end of the tubular portion 201. The side plate 202 is connected to one of two members that can be switched between a state in which relative rotation is disabled and a state in which relative rotation is enabled by a friction clutch device configured including the clutch hub 200.

[0008] The cylindrical portion 201 has a male spline portion 203 on its outer circumferential surface. A first friction plate and a second friction plate are disposed on the radially outer side of the cylindrical portion 201.

[0009] One of the first friction plate and the second friction plate is supported by having its inner periphery splined to the male spline portion 203, allowing relative axial displacement with respect to the cylindrical portion 201 but preventing relative rotation.

[0010] The other of the first friction plate and the second friction plate is supported so as to be capable of relative axial displacement but not rotation relative to the tubular member by spline-engaging its outer circumferential portion with a female spline portion provided on the inner circumferential surface of the tubular member connected to the other of the two members.

[0011] This allows the first friction plate and the second friction plate to be displaced relative to each other in the axial direction, making it possible to press the first friction plate and the second friction plate against each other to prevent relative rotation between the two members, and to release the force pressing the first friction plate and the second friction plate against each other to allow relative rotation between the two members.

[0012] 21 , the cylindrical portion 201 further has oil holes 204 penetrating radially at a plurality of locations in the circumferential direction, and an uneven portion 207 provided on the inner circumferential surface and made up of concave and convex portions 205 and convex portions 206 arranged alternately in the circumferential direction. The radially inner ends of the oil holes 204 open into the concave portions 205. One axial end of the concave portions 205 is closed by the side plate portion 202, and the other axial end of the concave portions 205 is open.

[0013] When a friction clutch device including clutch hub 200 is in operation, lubricating oil is supplied from a lubricating oil supply unit to a radially inner region of cylindrical portion 201 of clutch hub 200. The lubricating oil supplied to this region moves radially outward through this region due to the effects of centrifugal force and gravity, and reaches the inner circumferential surface of cylindrical portion 201. The lubricating oil that has reached the inner circumferential surface of cylindrical portion 201 flows into recesses 205 that form uneven portion 207, and further flows out radially outward of cylindrical portion 201 through oil holes 204, thereby lubricating the first friction plates and the second friction plates.

[0014] 22(a) and 22(b) show a clutch hub 200a of a second example of a conventional structure described in Japanese Patent Laid-Open Publication No. 2006-077888. Similar to the clutch hub 200 of the first example of a conventional structure, the clutch hub 200a includes a cylindrical portion 201a having a male spline portion 203a, oil holes 204a, and an uneven portion 207a, and a side plate portion 202a bent radially inward from one axial end of the cylindrical portion 201a. The cylindrical portion 201a further includes a dam portion 208 at the other axial end of the recess 205a, among the recesses 205a and protrusions 206a that constitute the uneven portion 207a, for damming up lubricating oil flowing along the inner surface of the recess 205a to the other axial end. [Prior art documents] [Patent documents]

[0015] [Patent Document 1] International Publication No. WO2022 / 074958 [Patent Document 2] Japanese Patent Application Publication No. 2019-168101 [Patent Document 3] Japanese Patent Application Laid-Open No. 2006-077888 Summary of the Invention [Problem to be solved by the invention]

[0016] In the two-speed transmission described in International Publication WO 2022 / 074958, in order to achieve size reduction and / or structural simplification, it is conceivable to make the outer diameter of the portion of the rotating member onto which the second friction plate constituting the first engagement device is fitted equal to the outer diameter of the portion onto which the inner diameter cylindrical member constituting the second engagement device is fitted. In this case, it is conceivable to use a clutch hub 200 of a first example of a conventional structure described in Japanese Patent Application Laid-Open No. 2019-168101 or a clutch hub 200a of a second example of a conventional structure described in Japanese Patent Application Laid-Open No. 2006-077888 instead of the stepped cylindrical member constituting the rotating member. Specifically, a second friction plate can be fitted onto one axial side portion of male spline portions 203, 203a of clutch hubs 200, 200a so as to allow relative axial displacement but prevent relative rotation, and an inner diameter cylindrical member can be fitted onto the other axial side portion of male spline portions 203, 203a.

[0017] However, clutch hub 200 of the first example of conventional structure and clutch hub 200a of the second example of conventional structure are not designed with the intention of fitting two different components onto male spline portions 203, 203a. For this reason, it may not be possible to supply a sufficient amount of lubricating oil to the area between the first friction plate and the second friction plate that make up the first engagement device, and / or the area between the inner diameter side cylindrical member and the outer diameter side member that make up the second engagement device.

[0018] In clutch hub 200 of the first example of the conventional structure, of the lubricating oil supplied from the lubricating oil supply portion and reaching the inner circumferential surface of cylindrical portion 201, a portion of the lubricating oil adhering to the bottom surfaces of recesses 205 constituting uneven portion 207 is supplied radially outward from cylindrical portion 201 through oil holes 204. The remaining lubricating oil adhering to the bottom surfaces of recesses 205 moves to the other axial side as shown by arrow A1 in FIG. 21 and flows out radially outward from the other axial end of cylindrical portion 201. Furthermore, most of the lubricating oil adhering to the radially inner surfaces of protrusions 206 constituting uneven portion 207 moves to the other axial side as shown by arrow A2 in FIG. 21 and flows out radially outward from the other axial end of cylindrical portion 201. In other words, most of the lubricating oil that reaches the inner circumferential surface of cylindrical portion 201 flows out radially outward from the other axial end of cylindrical portion 201 without passing through oil holes 204.

[0019] In clutch hub 200a of the second example of the conventional structure, of the lubricating oil supplied from the lubricating oil supply portion and reaching the inner circumferential surface of cylindrical portion 201a, the lubricating oil that has entered recesses 205a that constitute uneven portion 207a is prevented by dam portion 208 from moving to the other axial side as shown by arrow B1 in Fig. 22(b) and flowing radially outward from the other axial end of cylindrical portion 201. However, of the lubricating oil supplied from the lubricating oil supply portion and reaching the inner circumferential surface of cylindrical portion 201a, the lubricating oil that has adhered to the radially inner surfaces of protrusions 206a that constitute uneven portion 207a moves to the other axial side as shown by arrow B2 in Fig. 22(b) and flows radially outward from the other axial end of cylindrical portion 201.

[0020] The present disclosure aims to provide a clutch hub that can be fitted with two different components and has a structure that makes it easy to ensure the amount of lubricating oil supplied to these components, and a two-speed transmission that is equipped with the clutch hub. [Means for solving the problem]

[0021] A clutch hub according to one aspect of the present disclosure includes: a cylindrical portion having a first engagement portion disposed on one axial side of the outer peripheral surface and with which a component constituting a friction clutch device is engaged, a second engagement portion disposed on the other axial side of the outer peripheral surface and with which a component constituting a device other than the friction clutch device is engaged, and oil holes passing radially through a plurality of locations within the same axial range as the first engagement portion; a side plate portion extending radially inward from one axial end of the cylindrical portion; Equipped with The cylindrical portion has a damming surface facing one axial side in an axially intermediate portion of the inner circumferential surface that is located on the other axial side of the oil hole, and the inner diameter of the damming surface is equal to or smaller than the inner diameter of the smallest inner diameter portion of the inner circumferential surface that is located on the one axial side of the damming surface.

[0022] In a clutch hub according to one aspect of the present disclosure, The cylindrical portion may have a male spline portion on the outer circumferential surface, the male spline portion being formed by alternately arranging recessed portions and protruding portions in the circumferential direction, In this case, the first engagement portion is formed by a portion on one axial side of the male spline portion, and the second engagement portion is formed by a portion on the other axial side of the male spline portion.

[0023] In a clutch hub according to one aspect of the present disclosure, The cylindrical portion is a one-side concave-convex portion formed by alternately arranging concave and convex portions in the circumferential direction and provided in a portion of the inner circumferential surface that radially overlaps with the first engagement portion; a second-side concave-convex portion formed by alternately arranging concave and convex portions in the circumferential direction and provided in a portion of the inner circumferential surface that radially overlaps with the second engagement portion; a circumferential convex wall portion formed on the inner circumferential surface at a portion adjacent to one axial side of the other-side concave-convex portion; The inner circumferential surface may have a circumferential groove formed in a portion between the one-side uneven portion and the other-side uneven portion.

[0024] In this case, a radially inner end of the oil hole opens into the recess of the one-side uneven portion, The blocking surface is constituted by a surface of the inner surface of the circumferential groove facing one axial side and a side surface of the circumferential protruding wall portion on one axial side.

[0025] In a clutch hub according to one aspect of the present disclosure, The circumferential groove is formed at the end of the convex portion of the one-side uneven portion on the other axial side so as to circumferentially cross the end of the convex portion on the other axial side. In this case, the circumferential groove is arranged adjacent to one axial side of the circumferential convex wall portion. More specifically, the circumferential groove is formed at the end of the convex portion of the one-side uneven portion on the other axial side and is composed of circumferential groove pieces that exist intermittently in the circumferential direction.

[0026] In a clutch hub according to one aspect of the present disclosure, the circumferential groove is formed in an axially intermediate portion of the circumferential protruding wall portion.

[0027] In a clutch hub according to one aspect of the present disclosure, it is preferable that the blocking surface be formed around the entire circumference. More specifically, the circumferential convex wall portion is formed around the entire circumference on a portion of the inner circumferential surface adjacent to one axial side of the other-side uneven portion, and the circumferential groove, more specifically, the circumferential groove piece is formed at the end of all of the convex portions of the one-side uneven portion on the other axial side. Alternatively, the circumferential convex wall portion is formed around the entire circumference on a portion of the inner circumferential surface adjacent to one axial side of the other-side uneven portion, and the circumferential groove is formed around the entire circumference in an axially intermediate portion of the circumferential convex wall portion. In this case, the radially inner end of the oil hole can open to some of the recesses of the one-side uneven portion, or can open to all of the recesses of the one-side uneven portion.

[0028] In a clutch hub according to one aspect of the present disclosure, the oil holes and the damming surfaces can be disposed in only some of the recesses in the one-side uneven portion in the circumferential direction. More specifically, the oil holes, the circumferential convex wall portion, and the circumferential groove are not disposed in at least one of the recesses in the one-side uneven portion and the recesses in the other-side uneven portion, and the recesses in the one-side uneven portion and the recesses in the other-side uneven portion are configured to be continuous with the same inner diameter.

[0029] In a clutch hub according to one aspect of the present disclosure, the cylindrical portion has a circumferential protrusion formed over the entire circumference at an intermediate portion of the axial direction of the inner peripheral surface, The blocking surface is formed by a side surface on one axial side of the circumferential protrusion.

[0030] In a clutch hub according to one aspect of the present disclosure, The cylindrical portion is a locking groove formed in the axially intermediate portion of the inner peripheral surface and extending in a circumferential direction; a ring-shaped member having a radially outer portion locked in the locking groove; Including, The circumferential protrusion is formed by a portion of the ring-shaped member that protrudes radially inward from the locking groove, i.e., a radially inner portion.

[0031] A two-speed transmission according to one embodiment of the present disclosure includes: an input member rotatably supported relative to a fixed portion that does not rotate even during use; an output member supported coaxially with the input member and capable of rotating relative to the input member; a rotating member supported coaxially with the input member and the output member and capable of rotating relative to the input member and the output member; a friction engagement portion having a first friction plate and a second friction plate supported to allow relative axial displacement, the friction engagement portion being provided between the input member or the output member and the rotating member, the friction engagement portion pressing the first friction plate and the second friction plate against each other to switch the input member or the output member and the rotating member to a state in which they rotate integrally, and releasing the force pressing the first friction plate and the second friction plate against each other to switch the input member or the output member and the rotating member to a state in which they rotate relatively; an engagement device provided between the fixed portion and the rotating member, which switches the rotating member between a rotatable state and a non-rotatable state relative to the fixed portion; a planetary reduction mechanism including a sun element, a ring element disposed around the sun element, a carrier disposed between the sun element and the ring element in the radial direction, and a plurality of planetary elements rotatably supported by the carrier and engaged with the sun element and the ring element to enable torque transmission; Equipped with an input element, which is any one of the sun element, the ring element, and the carrier, is connected to the input member so as to rotate integrally with the input member; an output element, which is one of the sun element, the ring element, and the carrier and is an element separate from the input element, is connected to the output member so as to rotate integrally with the output member; Rotating elements, which are the remaining elements of the sun element, the ring element, and the carrier excluding the input element and the output element, are connected to the rotating member so as to rotate integrally with the rotating member, the rotating member includes a clutch hub according to one aspect of the present disclosure; the first friction plate or the second friction plate engages with the first engagement portion of the cylindrical portion, A component constituting the engagement device is engaged with the second engagement portion of the cylindrical portion. [Effects of the Invention]

[0032] According to the clutch hub and two-speed transmission according to one embodiment of the present disclosure, two different components can be fitted onto the outside, and the amount of lubricant oil supplied to these components can be easily ensured. [Brief explanation of the drawings]

[0033] [Figure 1] FIG. 1 is a schematic cross-sectional view of a drivetrain incorporating a clutch hub according to a first embodiment of the present disclosure and a two-speed transmission including the clutch hub. [Figure 2] Figure 2(a) is a schematic cross-sectional view showing the torque transmission path in the low reduction ratio mode of the two-speed transmission of the first example, and Figure 2(b) is a schematic cross-sectional view showing the torque transmission path in the high reduction ratio mode of the two-speed transmission of the first example. [Figure 3] FIG. 3 is a cross-sectional view of the two-speed transmission of the first example. [Figure 4] FIG. 4 is a cross-sectional view of the two-speed transmission of the first example, with some parts omitted. [Figure 5] FIG. 5 is an exploded perspective view showing the first friction plate and the second friction plate that constitute the friction clutch device of the two-speed transmission of the first example. [Figure 6] FIG. 6 is an enlarged view of part A in FIG. [Figure 7] FIG. 7 is a perspective view showing a drive cam taken out from a pressing device that constitutes the friction clutch device. [Figure 8] FIG. 8 is an exploded perspective view showing the driven cam and the rolling element removed from the pressing device. [Figure 9] FIG. 9 is a perspective view of the clutch hub of the first example. [Figure 10] FIG. 10 is a cross-sectional view of the clutch hub of the first example. [Figure 11] 11(a) is an enlarged view of a portion B1 in FIG. 10, and FIG. 11(b) is an enlarged view of a portion B2 in FIG. [Figure 12]Figure 12(a) is a schematic cross-sectional view showing the torque transmission path in the low reduction ratio mode of a two-speed transmission in a second example of an embodiment of the present disclosure, and Figure 12(b) is a schematic cross-sectional view showing the torque transmission path in the high reduction ratio mode of the two-speed transmission in the second example. [Figure 13] FIG. 13 is a perspective view of a clutch hub according to a third example of an embodiment of the present disclosure. [Figure 14] FIG. 14 is a cross-sectional view of a clutch hub according to a third example. [Figure 15] 15(a) is an enlarged view of a portion C1 in FIG. 14, and FIG. 15(b) is an enlarged view of a portion C2 in FIG. [Figure 16] FIG. 16 is a perspective view of a clutch hub according to a fourth example of an embodiment of the present disclosure. [Figure 17] FIG. 17 is a perspective view of a clutch hub according to a fifth example of an embodiment of the present disclosure. [Figure 18] FIG. 18 is a cross-sectional view of a clutch hub according to a fifth example. [Figure 19] FIG. 19 is a cross-sectional view of a clutch hub according to a sixth example of an embodiment of the present disclosure. [Figure 20] FIG. 20 is an enlarged view of part D in FIG. [Figure 21] FIG. 21 is a perspective view of a clutch hub of a first example of a conventional structure. [Figure 22] FIG. 22(a) is a view of a circumferential portion of a radially outer end of a clutch hub of a second example of a conventional structure, as viewed from the axial direction, and FIG. 22(b) is an E-E cross-sectional view of FIG. 22(a). DETAILED DESCRIPTION OF THE INVENTION

[0034] [Example 1] A first example of an embodiment of the present disclosure will be described with reference to FIGS. 1 to 11(b).

[0035] (Basic configuration of a two-speed transmission) The two-speed transmission 1 in this example is a two-speed transmission applicable to automobiles including electric vehicles and hybrid vehicles, and is arranged between a drive source 2 such as an electric motor or engine and a differential device 3, and transmits the output torque of the drive source 2 to the differential device 3 while increasing (decelerating) or without increasing it.

[0036] The two-speed transmission 1 includes an input member 4, an output member 5, a rotating member 6, a friction engagement portion 46, an engagement device 8, and a planetary reduction mechanism 9.

[0037] In the following description, unless otherwise specified, the axial direction, radial direction, and circumferential direction refer to the axial direction, radial direction, and circumferential direction of the input member 4. The axial direction, radial direction, and circumferential direction of the input member 4 coincide with the axial direction, radial direction, and circumferential direction of the output member 5, and also coincide with the axial direction, radial direction, and circumferential direction of the rotating member 6. Furthermore, one axial side refers to the right side in Figs. 1 to 4, and the other axial side refers to the left side in Figs. 1 to 4.

[0038] The input member 4 is rotatably supported by a fixed portion 72 that does not rotate even during use. The input member 4 can be rotationally driven by the drive source 2, and receives the output torque of the drive source 2. In this example, the input member 4 is formed by a housing that houses the two-speed transmission 1, and is rotatably supported by a rolling bearing (not shown) or the like, by the fixed portion 72 that does not rotate even during use.

[0039] In this example, the input member 4 is cylindrical (hollow). The input member 4 has an input gear 12 at one axial end thereof, which meshes with a drive gear 11 provided on an output shaft 10 of the drive source 2.

[0040] The output member 5 is supported coaxially with the input member 4 and rotatable relative to the input member 4. The output member 5 is connected to the input portion of the differential device 3 so as to be able to transmit torque. In this example, the output member 5 is supported radially inside the cylindrical input member 4 via a planetary reduction mechanism 9 so as to be rotatable relative to the input member 4. The output member 5 also has an output gear 13 at one end on the axial side. The output gear 13 meshes with a gear provided at the input portion of the differential device 3.

[0041] The rotating member 6 is supported coaxially with the input member 4 and the output member 5 and is capable of relative rotation with respect to the input member 4 and the output member 5. In this example, the rotating member 6 is rotatably supported with respect to the fixed part 72 via the planetary reduction mechanism 9, the pressing device 49 that constitutes the friction clutch device 7, the bearing device 67, and the like.

[0042] The friction engagement portion 46 has at least one first friction plate 55 and one second friction plate 56 that are supported to allow relative displacement in the axial direction. In this example, the friction engagement portion 46 is configured by alternately stacking a plurality of first friction plates 55 and a plurality of second friction plates 56.

[0043] The frictional engagement portion 46 is provided between the input member 4 or the output member 5 and the rotating member 6, and has the function of pressing the first friction plate 55 and the second friction plate 56 against each other to switch to a state in which the input member 4 or the output member 5 and the rotating member 6 rotate together, and of releasing the force pressing the first friction plate 55 and the second friction plate 56 against each other to switch to a state in which the input member 4 or the output member 5 and the rotating member 6 rotate relatively to each other. In this example, the frictional engagement portion 46 is provided between the input member 4 and the rotating member 6, and has the function of pressing the first friction plate 55 and the second friction plate 56 against each other to switch to a state in which the input member 4 and the rotating member 6 rotate together, and of releasing the force pressing the first friction plate 55 and the second friction plate 56 against each other to switch to a state in which the input member 4 and the rotating member 6 rotate relatively to each other.

[0044] The engagement device 8 is provided between the fixed portion 72 and the rotary member 6, and has the function of switching the rotary member 6 between a rotatable state and a non-rotatable state relative to the fixed portion 72.

[0045] The planetary reduction mechanism 9 has a sun element 105, a ring element 106 arranged around the sun element 105, a carrier 107 arranged radially between the sun element 105 and the ring element 106, and a plurality of planetary elements 108 engaged with the sun element 105 and the ring element 106 to enable torque transmission and supported rotatably on the carrier 107.

[0046] In the two-speed transmission 1, the input member 4, the output member 5, the first friction plate 55 and the second friction plate 56 of the friction engagement portion 46, and the outer diameter side member 101 and the inner diameter side member 102 of the engagement device 8 are connected to the sun element 105, the ring element 106, the carrier 107, or the fixed portion 72 so that the reduction ratio between the input member 4 and the output member 5 can be switched between two levels, high and low, by switching the mode of the friction engagement portion 46 and the mode of the engagement device 8.

[0047] Specifically, an input element, which is any one of sun element 105, ring element 106, and carrier 107, is connected to input member 4 so as to rotate integrally with the input member 4. An output element, which is any one of sun element 105, ring element 106, and carrier 107 and is an element other than the input element, is connected to output member 5 so as to rotate integrally with the output member 5. Furthermore, the remaining rotating elements, which are the sun element 105, ring element 106, and carrier 107 excluding the input element and the output element, are connected to rotating member 6 so as to rotate integrally with the rotating member 6.

[0048] For example, ring element 106 can be connected to input member 4 to rotate integrally therewith, carrier 107 can be connected to output member 5 to rotate integrally therewith, and sun element 105 can be connected to rotating member 6 to rotate integrally therewith.

[0049] Alternatively, the sun element 105 can be connected to the input member 4 to rotate integrally therewith, the carrier 107 can be connected to the output member 5 to rotate integrally therewith, and the ring element 106 can be connected to the rotating member 6 to rotate integrally therewith.

[0050] Alternatively, the sun element 105 can be connected to the input member 4 to rotate integrally therewith, the ring element 106 can be connected to the output member 5 to rotate integrally therewith, and the carrier 107 can be connected to the rotating member 6 to rotate integrally therewith.

[0051] In particular, the two-speed transmission 1 of this embodiment is characterized in that the rotating member 6 is configured to include the clutch hub 15 of this embodiment.

[0052] In this example, the rotary member 6 is constructed by joining and fixing a shaft member 14 and a clutch hub 15 together.

[0053] The shaft member 14 has a stepped cylindrical shape. Specifically, the shaft member 14 has, in order from one axial end, a large-diameter cylindrical portion 16, a medium-diameter cylindrical portion 17, and a small-diameter cylindrical portion 18. The shaft member 14 also has a through-hole 19 that passes through the center of the shaft member 14 in the axial direction and allows lubricating oil to flow through.

[0054] In this example, the large-diameter cylindrical portion 16 has a locking groove 20 around the entire circumference on the outer peripheral surface of one axial side portion. In addition, the large-diameter cylindrical portion 16 has a protrusion 21 around the entire circumference at the end on the other axial side that protrudes radially outward beyond the portion adjacent to the one axial side. The protrusion 21 has a fitting surface 22 provided on the outer peripheral surface of the one axial side portion, and a step surface 23 that bends radially outward from the end on the other axial side of the fitting surface 22 and faces the one axial side.

[0055] (clutch hub) The clutch hub 15 of this example has a cylindrical portion 24 and a side plate portion 25 that extends radially inward from one axial end of the cylindrical portion 24.

[0056] The cylindrical portion 24 is configured to have a generally cylindrical shape as a whole, and has a first engagement portion 26, a second engagement portion 27, an oil hole 28, and a blocking surface 29.

[0057] The first engagement portion 26 is disposed on one axial side portion of the outer peripheral surface of the cylindrical portion 24. A component constituting the friction clutch device 7 is engaged with the first engagement portion 26. In this example, a second friction plate 56 constituting the friction clutch device 7 is engaged with the first engagement portion 26.

[0058] The second engagement portion 27 is disposed on the other axial side portion of the outer peripheral surface of the cylindrical portion 24. A component constituting a device other than the friction clutch device is engaged with the second engagement portion 27. In this example, the inner diameter side member 102 of the engagement device 8 is engaged with the second engagement portion.

[0059] The oil holes 28 penetrate the cylindrical portion 24 in the radial direction at a plurality of locations in the same axial range as the first engagement portion 26 .

[0060] In particular, clutch hub 15 of this example is characterized by having a damming surface 29. The damming surface 29 is provided on the inner circumferential surface of cylindrical portion 24 in an axially intermediate portion that is located on the other axial side of oil hole 28, and faces one axial side. The damming surface 29 has a structure in which its inner diameter is equal to or smaller than the smallest inner diameter of the portion of the inner circumferential surface of cylindrical portion 24 that is located on one axial side of damming surface 29.

[0061] In this example, clutch hub 15 is provided with damming surface 29 along the entire circumferential direction or along a portion of the circumferential direction. A portion of the lubricating oil supplied to the inner circumferential surface of cylindrical portion 24 of clutch hub 15, specifically, the lubricating oil supplied to the inner circumferential surface of cylindrical portion 24 of clutch hub 15 on one axial side of damming surface 29, flows to the other axial side and moves to a portion adjacent to one axial side of damming surface 29. Because a force acting radially outward is applied to the lubricating oil due to the action of centrifugal force and gravity, the lubricating oil cannot easily overcome damming surface 29 and is blocked by damming surface 29. Therefore, by appropriately providing the blocking surface 29 over the entire circumferential direction or over part of the circumferential direction, it is possible to appropriately adjust whether the lubricating oil flows out radially outside the cylindrical portion 24 through the oil holes 28 or flows out radially outside the cylindrical portion 24 through the other axial side portion of the inner circumferential surface of the cylindrical portion 24 and / or the other axial side end face of the cylindrical portion 24. This makes it possible to appropriately supply lubricating oil to both the first engaging portion 26 and the second engaging portion 27 arranged on the same cylindrical portion 24 on the outer circumferential surface of the cylindrical portion 24.

[0062] In this example, the clutch hub 15 is applied to a two-speed transmission 1 for an automobile. However, the clutch hub 15 of this example is not limited to two-speed transmissions for automobiles, and can be incorporated into various mechanical devices that include a friction clutch device that switches whether or not a second member is allowed to rotate relative to a first member, and an engagement device that switches whether or not a third member is allowed to rotate relative to the first member.

[0063] The configuration of the cylindrical portion 24, specifically the structure of the outer peripheral surface and / or the inner peripheral surface of the cylindrical portion 24, can take various forms depending on the structure of the member to which the clutch hub 15 is assembled, or the structure of the members to be assembled to the first engagement portion 26 and the second engagement portion 27. The structure of the outer peripheral surface and / or the inner peripheral surface of the cylindrical portion 24 can be any structure such as a spline structure in which recesses and protrusions are alternately arranged in the circumferential direction, a structure consisting of a single cylindrical surface, or another structure in which an engagement structure with a mating member is provided on a single cylindrical surface.

[0064] In the clutch hub 15 of this example, the cylindrical portion 24 has, on its outer peripheral surface, a male spline portion 30 formed by alternately arranging recessed portions 31 and protruding portions 32 in the circumferential direction. The first engagement portion 26 is formed by a portion of the male spline portion 30 on one axial side, and the second engagement portion 27 is formed by a portion of the male spline portion 30 on the other axial side.

[0065] In this example, the cylindrical portion 24 has locking grooves 33a, 33b in portions of its outer peripheral surface that are located on both axial sides of the second engagement portion 27. The locking grooves 33a, 33b are configured by locking groove pieces that are formed so as to circumferentially cross each of the multiple protrusions 32 that make up the male spline portion 30.

[0066] The shape and size of the oil holes 28 are arbitrary as long as they allow the lubricating oil to flow out appropriately, and the opening shape of each oil hole 28 as viewed from the radial direction can be an oval, circle, rectangle, or other shape that extends in the axial direction as viewed from the radial direction. In this example, the opening shape of the oil holes 28 is an oval that extends in the axial direction.

[0067] The oil holes 28 may be arranged in any manner as long as the lubricating oil can be appropriately discharged. The oil holes 28 may be arranged one at a time at multiple locations around the circumference on one axial side of the cylindrical portion 24, or multiple oil holes 28 may be arranged at the same location around the circumference. In this example, the oil holes 28 are arranged one at a time at multiple locations around the circumference.

[0068] The oil holes 28 can be arranged so that the axial positions of adjacent oil holes 28 in the circumferential direction are shifted from each other, or so that the axial positions of adjacent oil holes 28 coincide with each other. In this example, the oil holes 28 are arranged so that the axial positions of adjacent oil holes 28 in the circumferential direction are shifted from each other.

[0069] In this example, the cylindrical portion 24 further has a one-side uneven portion 34 , an other-side uneven portion 35 , a circumferential protruding wall portion 36 , and a plurality of circumferential groove pieces 117 .

[0070] The one-side uneven portion 34 is provided on a portion of the inner circumferential surface of the cylindrical portion 24 that overlaps with the first engagement portion 26 in the radial direction, and is composed of recesses 38 and protrusions 39 arranged alternately in the circumferential direction.

[0071] In this example, the recess 38 that constitutes the one-side uneven portion 34 is arranged in a portion that radially overlaps with the protrusion 32 that constitutes the male spline portion 30, and the protrusion 39 that constitutes the one-side uneven portion 34 is arranged in a direction that radially overlaps with the recess 31 that constitutes the male spline portion 30.

[0072] In this example, the oil holes 28 are arranged one by one at the same circumferential position as the recessed portions 38 of the one-side uneven portion 34. The radially inner end of each oil hole 28 opens into the recessed portions 38 of the one-side uneven portion 34, and the radially outer end of each oil hole 28 opens into the protruding portions 32 of the male spline portion 30.

[0073] The other-side uneven portion 35 is provided on the inner circumferential surface of the cylindrical portion 24 in a portion that overlaps the second engagement portion 27 in the radial direction, and is formed by alternately arranging recesses 40 and protrusions 41 in the circumferential direction.

[0074] In this example, the recess 40 that constitutes the other side uneven portion 35 is arranged in a portion that radially overlaps with the protrusion 32 that constitutes the male spline portion 30, and the protrusion 41 that constitutes the other side uneven portion 35 is arranged in a direction that radially overlaps with the recess 31 that constitutes the male spline portion 30.

[0075] In this example, the inscribed circle diameter of the bottom surface of the recess 38 of the one-side uneven portion 34 is equal to the inscribed circle diameter of the bottom surface of the recess 40 of the other-side uneven portion 35. In addition, the inscribed circle diameter of the radially inner surface of the protrusion 39 of the one-side uneven portion 34 is equal to the inscribed circle diameter of the radially inner surface of the protrusion 41 of the other-side uneven portion 35.

[0076] That is, in this example, the cylindrical portion 24 has an end face shape that is wavy in a substantially rectangular wave shape in the circumferential direction when viewed from the axial direction. In this example, by adopting such a configuration, the thickness of the cylindrical portion 24 is substantially constant over the entire circumference, which makes it easy to reduce the weight of the cylindrical portion 24.

[0077] The circumferential protruding wall portion 36 is formed on a portion of the inner peripheral surface of the cylindrical portion 24 that is adjacent to one axial side of the other-side uneven portion 35. In this example, the circumferential protruding wall portion 36 is provided around the entire circumference in a portion that radially overlaps with the locking groove 33a on one axial side of the two locking grooves 33a, 33b provided on the outer peripheral surface of the cylindrical portion 24.

[0078] In this example, the inner diameter of the circumferential convex wall portion 36, more specifically, the inner diameter of the radially inner surface which is the inner peripheral surface of the circumferential convex wall portion 36, can be smaller than the inner diameters of the convex portions 39 of the one-side uneven portion 34 and the convex portions 41 of the other-side uneven portion 35, more specifically, the inscribed circle diameter of the radially inner surface of the convex portions 39 of the one-side uneven portion 34 and the inscribed circle diameter of the radially inner surface of the convex portions 41 of the other-side uneven portion 35 (the circumferential convex wall portion 36 protrudes radially inward more than the convex portions 39 and 41), or it can be equal (the radially inner surface of the circumferential convex wall portion 36 is arranged on the same imaginary cylindrical surface as the radially inner surface of the convex portions 39 and the radially inner surface of the convex portions 41), or it can be larger (the circumferential convex wall portion 36 is recessed radially outward more than the convex portions 39 and 41). The inner diameter of the circumferential protruding wall portion 36 is preferably equal to the inner diameter of the protrusions 39 and 41 .

[0079] In this example, the inner diameter of the radially inner surface, which is the inner peripheral surface of the circumferential convex wall portion 36, is equal to the inscribed circle diameter of the radially inner surface of the convex portion 39 of the one-side uneven portion 34 and the inscribed circle diameter of the radially inner surface of the convex portion 41 of the other-side uneven portion 35. Therefore, the radially inner surface of the convex portion 41 of the other-side uneven portion 35 and the radially inner surface of the circumferential convex wall portion 36 are smoothly continuous without any steps.

[0080] The end portion on one axial side of the convex portion 41 of the other-side uneven portion 35 is continuous with the end portion on the other axial side of the circumferential convex wall portion 36 (the radially inner surface of the convex portion 41 and the radially inner surface of the circumferential convex wall portion 36 are smoothly continuous without any steps). The inner diameter of the concave portion 40 of the other-side uneven portion 35, more specifically, the inner diameter of the radially inner surface of the concave portion 40, is larger than the inner diameter of the circumferential convex wall portion 36. Therefore, the end portion on one axial side of the concave portion 40 is blocked by the side surface of the circumferential convex wall portion 36 on the other axial side.

[0081] The circumferential groove 37 is formed in a portion of the inner circumferential surface of the cylindrical portion 24 between the one-side uneven portion 34 and the other-side uneven portion 35. More specifically, the circumferential groove 37 is formed in a portion adjacent to one axial side of the circumferential protruding wall portion 36, or in an axially intermediate portion of the circumferential protruding wall portion 36.

[0082] In this example, the circumferential groove 37 is formed at the other axial end of the convex portion 39 of the one-side uneven portion 34 so as to circumferentially cross the other axial end of the convex portion 39. Therefore, the circumferential groove 37 is disposed adjacent to one axial side of the circumferential convex wall portion 36. More specifically, the circumferential groove 37 is constituted by circumferential groove pieces 117 formed at the other axial end of each of the convex portions 39 of the one-side uneven portion 34.

[0083] The shape of the circumferential groove 37 is arbitrary as long as the side surface on the other axial side of the circumferential groove 37 can form the damming surface 29. The shape of the circumferential groove 37 may be a cross-sectional shape such as a concave arc shape, a concave rectangle, or a V-shape. In this example, the circumferential groove 37 (circumferential groove piece 117) has a cross-sectional shape that is a concave arc shape with the axial center being the deepest part, as shown in FIG. 11(a).

[0084] The size of the circumferential groove 37 is arbitrary as long as the side surface of the circumferential groove 37 on the other axial side can form the damming surface 29. The radial depth of the circumferential groove 37 can be shallower than the radial depth of the recessed portion 38 of the one-side uneven portion 34, the same as the radial depth of the recessed portion 38, or deeper than the radial depth of the recessed portion 38. In this example, the radial depth of the circumferential groove 37 (the radial depth of the deepest portion) is shallower than the recessed portion 38 of the one-side uneven portion 34.

[0085] In this example, the damming surface 29 is constituted by a surface of the inner surface of the circumferential groove 37 facing one axial side and a side surface of the circumferential convex wall portion 36 on one axial side. That is, for the lubricating oil flowing in the other axial direction through the recesses 38 of the one-side uneven portion 34, the side surface on one axial side of the circumferential convex wall portion 36 that closes the end portion on the other axial side of the recesses 38 functions as the damming surface 29. Furthermore, for the lubricating oil flowing in the other axial direction through the protrusions 39 of the one-side uneven portion 34, the surface of the inner surface of the circumferential groove 37 facing one axial side functions as the damming surface 29.

[0086] The inner diameter of the blocking surface 29 is equal to or smaller than the inner diameter of the smallest portion of the inner circumferential surface of the cylindrical portion 24 that is located on one axial side of the blocking surface 29. In this example, the inner diameter of the blocking surface 29 is the same as the inscribed circle diameter of the convex portion 39 that is the smallest portion of the inner circumferential surface of the cylindrical portion 24 that is located on one axial side of the blocking surface 29.

[0087] In the clutch hub 15 of this example, the damming surfaces 29 can be formed over the entire circumference, i.e., the damming surfaces 29 can be arranged on all of the recessed portions 38 and protruding portions 39 of the one-side uneven portion 34. Alternatively, the damming surfaces 29 can be arranged on only some of the recessed portions 38 in the circumferential direction among the recessed portions 38 of the one-side uneven portion 34. In this case, the damming surfaces 29 are arranged on all of the protruding portions 39 of the one-side uneven portion 34, but not on some of the recessed portions 38. No oil holes 28 can be arranged in some of the recessed portions 38 where the damming surfaces 29 are not formed, and the oil holes 28 can be arranged only in the remaining recessed portions 38 where the damming surfaces 29 are formed.

[0088] Because the damming surfaces 29 are not provided, i.e., the oil holes 28, the circumferential convex wall portions 36, and the circumferential grooves 37 are not provided, and the recesses 38 of the one-side uneven portion 34 and the recesses 40 of the other-side uneven portion 35 are continuous with the same inner diameter, the lubricating oil flowing through the recesses 38 to the other axial side flows out radially outward via the recesses 40 and the end portion and end face of the other axial side of the cylindrical portion 24. Therefore, by adjusting the number of recesses 38, 40 that do not have oil holes 28 and damming surfaces 29 to one or more, or by not providing any recesses 38, 40, it is possible to adjust the amount of lubricating oil that flows out radially outward through the oil holes 28 and the amount of lubricating oil that flows out radially outward through the end portion and end face of the other axial side of the cylindrical portion 24.

[0089] In this example, the circumferential convex wall portion 36 is formed around the entire inner surface of the tubular portion 24 in a portion adjacent to one axial side of the other-side uneven portion 35, and the circumferential groove 37 (circumferential groove piece 117) is formed at the other axial end of all the recesses 38 of the one-side uneven portion 34.

[0090] In the clutch hub 15 of this example, the side plate portion 25 is configured as a hollow circular plate as a whole, and has through holes 42 penetrating in the axial direction at a plurality of positions in the circumferential direction of the radially intermediate portion.

[0091] In this example, the shaft member 14 and the clutch hub 15 are joined and fixed by welding or the like with the radially inner portion of the side surface on the other axial side of the side plate portion 25 abutting against the step surface 23 and the inner surface of the side plate portion 25 fitted externally onto the mating surface portion 22.

[0092] During operation of a device such as the two-speed transmission 1 incorporating the clutch hub 15 of this example, lubricating oil is supplied to a radially inner region of the cylindrical portion 24 of the clutch hub 15 through a lubrication path such as the through-hole 19 of the shaft member 14. The lubricating oil supplied to the radially inner region of the cylindrical portion 24 moves radially outward from the region to the inner circumferential surface of the cylindrical portion 24 due to the action of centrifugal force and gravity, as shown by arrows α1 and α2 in Figure 10.

[0093] In this example, a portion of the lubricating oil supplied to the inner circumferential surface of the cylindrical portion 24 of the clutch hub 15, specifically, the lubricating oil supplied to the inner circumferential surface of the cylindrical portion 24 of the clutch hub 15 on one axial side of the dam surface 29, is collected in the recesses 38 of the one-side uneven portion 34 by the action of centrifugal force and gravity, and is then allowed to flow out radially to the outside of the cylindrical portion 24 through the oil holes 28, as shown by arrow β1 in Figure 10, thereby lubricating the friction engagement portion 46 having the first friction plate 55 and the second friction plate 56.

[0094] Furthermore, the remainder of the lubricating oil supplied to the inner surface of the cylindrical portion 24 of the clutch hub 15, specifically, the lubricating oil supplied to the inner surface of the cylindrical portion 24 of the clutch hub 15 on the other axial side of the dam surface 29, is collected in the recess 40 of the other-side uneven portion 35 by the action of centrifugal force and gravity, moves along the inner surface of the recess 40 to the other axial side, and flows out from the inner surface of the cylindrical portion 24, and further moves radially outward from the cylindrical portion 24 along the end face on the other axial side of the cylindrical portion 24, as shown by arrow β2 in Figure 10, thereby lubricating the engagement device 8 including the inner diameter side member 102.

[0095] In particular, in this example, the damming surface 29 facing one axial side is present around the entire circumference of the inner circumferential surface of the cylindrical portion 24 in an axially intermediate portion that is located on the other axial side of the oil hole 28. Therefore, the damming surface 29 can prevent the lubricating oil that is supplied to the inner circumferential surface of the cylindrical portion 24 on one axial side of the damming surface 29 from moving along the inner circumferential surface of the cylindrical portion 24 to the other axial side of the damming surface 29.

[0096] Specifically, on the inner peripheral surface of the cylindrical portion 24, of the lubricating oil supplied to one axial side of the damming surface 29, the lubricating oil that enters the recesses 38 of the one-side uneven portion 34 and moves to the other axial side is blocked by the side surface of the damming surface 29 on the one axial side of the circumferential convex wall portion 36 that is located at the same circumferential position as the recesses 38. The lubricating oil that moves to the other axial side along the radial inner surface of the convex portion 39 that constitutes the one-side uneven portion 34 is blocked by the surface of the damming surface 29 that faces one axial side of the circumferential groove piece 117 that is located at the same circumferential position as the convex portion 39.

[0097] The lubricating oil moving along the radial inner surface of the protrusion 39 toward the other axial direction enters the circumferential groove piece 117 and is blocked by the surface of the inner surface of the circumferential groove piece 117 facing one axial side, thereby preventing it from moving further toward the other axial direction, and moving along the circumferential groove piece 117 to the circumferentially adjacent recess 38.

[0098] As described above, in the clutch hub 15 of the present example, it is possible to prevent lubricating oil supplied to the inner circumferential surface of the cylindrical portion 24 on one axial side of the damming surface 29 from migrating along the inner circumferential surface of the cylindrical portion 24 to the other axial side of the damming surface 29. This makes it easy to appropriately control the ratio of lubricating oil supplied to the inner circumferential surface of the cylindrical portion 24 on one axial side of the damming surface 29 to lubricate the friction engagement portion 46 and the ratio of lubricating oil supplied to the other axial side of the damming surface 29 to lubricate the engagement device 8. This makes it easy to appropriately lubricate the friction engagement portion 46 and the engagement device 8.

[0099] (Specific configuration of two-speed transmission) In the two-speed transmission 1 of this example, a friction clutch device 7 is configured between the input member 4 and the rotating member 6. The friction clutch device 7 has the function of switching between a connected mode in which the input member 4 and the rotating member 6 rotate together, and a disconnected mode in which the input member 4 and the rotating member 6 rotate relative to each other.

[0100] The friction clutch device 7 includes a first member 43 , a rotating member 6 as a second member, a retaining ring 44 , a retaining ring 45 , a friction engagement portion 46 , a pressing plate 47 , an elastic member 48 , and a pressing device 49 .

[0101] The first member 43 is connected to the input member 4 and rotates integrally with the input member 4.

[0102] In this example, the first member 43 has a stepped cylindrical shape. Specifically, the first member 43 is configured by connecting a large-diameter cylindrical portion 50 on one axial side and a small-diameter cylindrical portion 51 on the other axial side by a connecting plate portion 52 in the shape of a hollow circular plate.

[0103] The first member 43 is connected to the input member 4 via a connecting member 53 configured as a generally hollow disk. Specifically, the radially outer end of the connecting member 53 is fitted and fixed to one axial end of the large-diameter cylindrical portion 50 of the first member 43, and the radially inner end of the connecting member 53 is fitted and fixed to the outside of an axial intermediate portion of the input member 4, so that the first member 43 is connected to the input member 4 so as to be rotatable integrally with it.

[0104] The first member 43 has a female spline portion 54 on the inner peripheral surface of the small diameter cylindrical portion 51, which is formed by alternately arranging recesses and protrusions in the circumferential direction.

[0105] The retaining ring 44 is fitted onto the outer peripheral surface of the large diameter cylindrical portion 16 of the rotating member 6, on the other axial side of the locking groove 20, without any radial play and allowing relative axial displacement.

[0106] The retaining ring 45 is engaged with the engaging groove 20 of the rotating member 6, and prevents the retaining ring 44 from being displaced to one side in the axial direction.

[0107] The first friction plate 55 constituting the friction engagement portion 46 has an end face shape that is approximately hollow and circular when viewed from the axial direction. The outer periphery of the first friction plate 55 is spline-engaged with the female spline portion 54 of the first member 43, so that the first friction plate 55 is supported so as to be able to move in the axial direction with respect to the small-diameter cylindrical portion 51 of the first member 43 but not to rotate relative to it.

[0108] The second friction plate 56 constituting the friction engagement portion 46 has an end face shape that is approximately hollow and circular when viewed in the axial direction. The inner peripheral portion of the second friction plate 56 is spline-engaged with the first engagement portion 26 of the cylindrical portion 24 of the rotating member 6, which is the second member, so that the second friction plate 56 is supported so as to be able to move in the axial direction with respect to the cylindrical portion 24 of the rotating member 6 but not to rotate relative to it.

[0109] Of the first friction plates 55 and the second friction plates 56 (among the plurality of first friction plates 55 and the plurality of second friction plates 56), the friction plate located furthest to the other axial side is prevented from displacing in the other axial direction by abutting the side surface on the other axial side against the side surface on one axial side of the annular retaining member 57 that is fitted externally so as to prevent relative rotation with respect to the tubular portion 24 and so as to prevent displacement in the other axial direction.

[0110] The retaining member 57 is prevented from rotating relative to the tubular portion 24 by spline-engaging its inner periphery with the first engagement portion 26, and is prevented from displacing in the other axial direction relative to the tubular portion 24 by a retaining ring 104a engaged in the engagement groove 33a of the tubular portion 24.

[0111] The friction engagement portion 46 may additionally include, as an optional component, a return spring that elastically biases the first friction plate 55 and the second friction plate 56 in a direction that separates them from each other.

[0112] The pressure plate 47 faces one axial side surface of the friction plate that is located furthest axially from the first friction plate 55 and the second friction plate 56, and is fitted onto the rotating member 6, which is the second member, so as to be able to move toward and away from the friction plate located furthest axially from the friction plate that is located furthest axially from the first friction plate.

[0113] The pressure plate 47 includes a circular ring portion 58 having a generally hollow circular end face shape when viewed in the axial direction, and a cylindrical portion 59 extending from the radially outer end of the circular ring portion 58 toward the other axial side.

[0114] The circular ring portion 58 is fitted onto the axially intermediate portion of the large-diameter cylindrical portion 16 of the rotating member 6 so as to allow relative axial displacement. The radially inner end of the side surface on the other axial side of the circular ring portion 58 faces the side surface on one axial side of the protruding portion 21. This prevents excessive displacement of the pressing plate 47 toward the other axial side.

[0115] The other axial end face of the cylindrical portion 59 faces one axial side face of the friction plate that is located furthest axially toward one side of the first friction plate 55 and the second friction plate 56 .

[0116] The elastic member 48 is sandwiched between the retaining ring 44 and the pressure plate 47, and elastically biases the pressure plate 47 toward the other axial side. That is, the elastic member 48 applies an elastic force to the first friction plate 55 and the second friction plate 56 in a direction pressing them against each other by causing the pressure plate 47 to press the friction plate that is located furthest toward one axial side, of the first friction plate 55 and the second friction plate 56, toward the other axial side.

[0117] The elastic member 48 may have any configuration, and may be made of any elastic material, such as a disc spring, a compression coil spring, or any other material. The number of pieces of elastic material that make up the elastic member is also arbitrary. In this example, the elastic member 48 is made up of one or more disc springs.

[0118] The pressing device 49 presses the pressing plate 47 toward one side in the axial direction.

[0119] In this example, the pressing device 49 includes a cam device 60 and a device for driving the cam device 60, such as an electric actuator 61.

[0120] The cam device 60 includes a driving cam 62 , a driven cam 63 , and a plurality of rolling elements 64 .

[0121] In this example, as shown in Fig. 8, rollers are used as the rolling elements 64, and the rolling elements 64 are supported so as to be able to rotate (spin) freely around a rotation axis C oriented in a radial direction from the central axis of the driven cam 63. In Figs. 1 to 2(b), the cam device 60 is shown schematically to make it easier to understand the invention.

[0122] As shown in Fig. 7, the drive cam 62 has a drive cam surface 65 on the radially inner part of one axial side surface, in which the same number of recesses 65a and protrusions 65b are arranged alternately in the circumferential direction. The drive cam 62 is supported by a support member 66, a bearing device 67, and a radial bearing 68 so as to be rotatable relative to the rotating member 6. Note that the support member 66 and the bearing device 67 are not shown in Figs. 1 to 2(b).

[0123] The support member 66 includes a circular ring portion 69 having a hollow circular end face shape when viewed in the axial direction, and a cylindrical portion 70 bent from the radially inner end of the circular ring portion 69 toward one side in the axial direction.

[0124] The support member 66 is supported and fixed to a fixed portion 72 by bolts (not shown) that are inserted into or screwed into mounting holes 71 provided at a plurality of locations in the circumferential direction of the circular ring portion 69 .

[0125] The bearing device 67 is composed of a double-row ball bearing and includes an inner ring 73 fitted onto the small diameter cylindrical portion 18 of the rotating member 6, an outer ring 74 fitted onto the cylindrical portion 70 of the support member 66, and a plurality of rolling elements 75 arranged to roll freely between the inner ring 73 and the outer ring 74.

[0126] The radial bearing 68 is composed of an angular contact ball bearing and includes an inner ring 76 fitted onto the other axial side portion of the cylindrical portion 70 of the support member 66, an outer ring 77 fitted onto the drive cam 62, and a plurality of balls 78 arranged to roll freely between the inner ring 76 and the outer ring 77.

[0127] In this example, the drive cam 62 has wheel teeth 79, which are helical gears, on its outer circumferential surface, and also has pin portions 80 that protrude toward one axial direction at multiple locations (three locations in the illustrated example) around the circumference of the radially middle portion of the side surface on one axial side. The tip portions of the pin portions 80 are engaged (fitted with play) with engagement holes provided in a select plate 103 that constitutes the engagement device 8. This causes the drive cam 62 and the select plate 103 to rotate integrally (at the same speed in the same direction).

[0128] 8, driven cam 63 is configured in the shape of a hollow circular plate, and has rectangular holes 81 penetrating in the axial direction at a plurality of locations (three locations in the illustrated example) around a radially intermediate portion, and has support plate portions 82a, 82b in the shape of approximately semicircular plates protruding toward the other axial side from both radially opposite portions of rectangular hole 81. Each of the support plate portions 82a on the radially outer side has support hole 83a which is a circular hole penetrating in the radial direction, and each of the support plate portions 82b on the radially inner side has support hole 83b which is a circular hole penetrating in the radial direction.

[0129] The driven cam 63 is disposed around the rotating member 6 so as to be displaceable only in the axial direction. Specifically, the driven cam 63 is supported so as to be displaceable only in the axial direction relative to the fixed portion 72 by spline-engaging a female spline portion 84 provided on the inner peripheral surface with a male spline portion 85 provided on the outer peripheral surface of one axial side portion of the cylindrical portion 70 of the support member 66, which is supported and fixed to the fixed portion 72.

[0130] Each of the plurality of rolling elements 64 has a cylindrical shape and is rotatably supported on the support plate portions 82a, 82b via a columnar support shaft 86 and a plurality of rollers 87. That is, both axial ends of the support shaft 86 are fitted and fixed in the support holes 83a, 83b. The plurality of rollers 87 are rollably sandwiched between the inner circumferential surface of the rolling element 64 and the outer circumferential surface of the axially middle portion of the support shaft 86. As a result, the rolling elements 64 are supported by the driven cam 63 so as to rotate (spin) about a rotation axis C that faces in a radial direction from the central axis of the driven cam 63. As shown in FIG. 6 , the other axial end of the outer circumferential surface of each rolling element 64 is in rolling contact with a drive cam surface 65 provided on a side surface on one axial side of the drive cam 62.

[0131] The rolling elements 64 constituting the cam device 60 are not limited to rollers and may be configured as desired, and may be configured with balls instead of rollers. In this case, in addition to or instead of the drive cam surface provided on the side surface on one axial side of the drive cam, a driven cam surface is formed on the side surface on the other axial side of the driven cam, in which the same number of recesses and protrusions are alternately arranged in the circumferential direction.

[0132] In the cam device 60, as the driving cam 62 rotates, the amount by which the rolling elements 64 ride up from the bottom of the recess 65a that constitutes the driving cam surface 65 increases or decreases, thereby displacing the driven cam 63 in the axial direction.

[0133] The driven cam 63 presses the pressure plate 47 toward one side in the axial direction via the pressure member 88 and the thrust bearing 89 .

[0134] The pressing member 88 has a base 90 and a plurality of pressing arms 91 .

[0135] The base 90 has an inner diameter side plate 92 in the form of a hollow circular plate, a cylindrical connecting tube 93 extending from the radially outer end of the inner diameter side plate 92 toward one axial side, and an outer diameter side plate 94 in the form of a hollow circular plate extending radially outward from one axial end of the connecting tube 93. The inner diameter side plate 92 of the base 90 is externally fitted onto the medium diameter tube 17 of the rotating member 6 without any radial rattle and allowing relative axial displacement.

[0136] Each pressing arm 91 protrudes toward one axial side from the radially outer end of the outer diameter side plate portion 94 of the base portion 90. Each pressing arm 91 is inserted into a through hole 42 provided in the side plate portion 25 of the clutch hub 15, with the tip end surface facing the radially middle portion of the side surface on the other axial side of the circular ring portion 58 of the pressing plate 47.

[0137] The thrust bearing 89 is configured by arranging a plurality of rolling elements 96 freely rollably between a pair of raceways 95a, 95b that are arranged coaxially and spaced apart in the axial direction. The thrust bearing 89 is arranged between a side surface on one axial side of the driven cam 63 and a side surface on the other axial side of the outer diameter side plate portion 94 of the pressing member 88.

[0138] The friction clutch device 7 of this example includes a preload applying member 97 for applying a preload to the thrust bearing 89, regardless of the axial dimension of the cam device 60. The preload applying member 97 is made up of a plurality of disc springs, compression coil springs, etc. In this example, the preload applying member 97 is made up of a plurality of disc springs.

[0139] The preload applying member 97 is sandwiched in an elastically compressed state between a side surface on one axial direction side of the inner diameter side plate portion 92 of the pressing member 88 and an end surface on the other axial direction side of the large diameter cylindrical portion 16 of the rotating member 6. The preload applying member 97 elastically attempts to restore its original shape, thereby elastically pressing the pressing member 88 toward the other axial direction side. This applies a preload to the thrust bearing 89 and prevents the thrust bearing 89 from falling out from between the driven cam 63 and the pressing member 88.

[0140] The cam device 60 is driven by an arbitrary drive device. In this example, the drive cam 62 is rotationally driven by an electric actuator 61. The electric actuator 61 includes an electric motor 98 and a reducer 99. The reducer 99 is configured by meshing a worm 100, which is rotationally driven by the electric motor 98, with wheel teeth 79 provided on the outer circumferential surface of the drive cam 62.

[0141] As a drive device for the cam device 60, a structure in which a spur gear or bevel gear provided on the output shaft of the electric motor is meshed with a spur gear or bevel gear provided on the drive cam 62, or a structure in which a belt or chain is stretched between the output shaft of the electric motor and the drive cam 62 can alternatively be adopted.

[0142] Alternatively, the cam device 60 may have a structure in which a driving cam surface provided on a driving cam and a driven cam surface provided on a driven cam are directly engaged (sliding), or a structure in which a driven cam has a guide groove that extends circumferentially on its outer circumferential surface and changes in the axial direction, and a driving cam has an engaging protrusion that engages with the guide groove to enable displacement along the guide groove. Alternatively, instead of a structure in which the cam device 60 and the electric actuator 61 are combined, a hydraulic cylinder device, a gas pressure cylinder device (including a pneumatic cylinder device), or the like may be used as the pressing device 49.

[0143] The friction clutch device 7 of this example controls the supply of electricity to the electric motor 98 and adjusts the rotational phase of the drive cam 62 to switch between a connection mode in which the first member 43 and the second member, the rotating member 6, rotate together, and a disconnection mode in which the first member 43 and the rotating member 6 rotate relative to each other.

[0144] The friction clutch device 7 can be configured as a so-called normally open clutch, in which the friction engagement portion 46 is connected (the first friction plate 55 and the second friction plate 56 are pressed against each other) by displacing the driven cam 63 in a direction that increases the axial distance between the driving cam 62 and the driven cam 63 based on the rotation of the driving cam 62, and the friction engagement portion 46 is disconnected (the force pressing the first friction plate 55 and the second friction plate 56 against each other is released) by displacing the driven cam 63 in a direction that decreases the axial distance between the driving cam 62 and the driven cam 63.

[0145] Alternatively, the friction clutch device 7 can be configured as a so-called normally closed clutch, in which the friction engagement portion 46 is connected (the first friction plate 55 and the second friction plate 56 are pressed against each other) by displacing the driven cam 63 in a direction that reduces the axial distance between it and the driving cam 62 based on the rotation of the driving cam 62, and the friction engagement portion 46 is disconnected (the force pressing the first friction plate 55 and the second friction plate 56 against each other is released) by displacing the driven cam 63 in a direction that increases the axial distance between it and the driving cam 62.

[0146] In this example, a normally-closed clutch is used. Specifically, to switch the friction clutch device 7 to the engagement mode, the electric motor 98 is energized to rotate the drive cam 62, thereby reducing the amount by which the rolling elements 64 climb above the bottom of the recess 65a of the drive cam surface 65. This causes the driven cam 63 to release the force pressing the pressure plate 47 toward one axial direction via the pressure member 88 and the thrust bearing 89. When the force pressing the pressure plate 47 toward one axial direction is released, the elastic restoring force of the elastic member 48 presses the pressure plate 47, the pressure member 88, and the thrust bearing 89 toward the other axial direction, and the pressure plate 47 presses the second friction plate 56, which is closest to one axial direction, toward the other axial direction. As a result, the first friction plate 55 and the second friction plate 56 press against each other, the friction clutch device 7 is engaged, and the first member 43 and the rotating member 6 rotate integrally.

[0147] To switch the friction clutch device 7 to the disengagement mode, the electric motor 98 is energized to rotate the drive cam 62, thereby increasing the amount by which the rolling elements 64 climb above the bottom of the recessed portion 65a of the drive cam surface 65. This causes the driven cam 63 to press the pressing plate 47 toward one axial direction via the pressing member 88 and thrust bearing 89, elastically contracting the axial dimension of the elastic member 48 and releasing the force pressing the first friction plates 55 and the second friction plates 56 against each other. As a result, the gap between the first friction plates 55 and the second friction plates 56 increases, the friction clutch device 7 is disengaged, and the first member 43 and the rotating member 6 become rotatable relative to each other.

[0148] In this example, the engagement device 8 can be configured, for example, as a mesh or friction clutch (brake device) whose mode can be switched by an actuator. The actuator for switching the clutch between engaged and disengaged states is not particularly limited, and a hydraulic actuator, an electromagnetic actuator, or the like can be used. In this example, the engagement device 8 is configured so that its mode can be switched based on the rotation of a drive cam 62 that constitutes the pressing device 49.

[0149] The engagement device 8 comprises an outer diameter side member 101 fitted and fixed to the inside of the fixed portion 72, an inner diameter side member 102 fitted and fixed to the outside of the cylindrical portion 24, at least one engagement pin (not shown), and a select plate 103.

[0150] The inner diameter side member 102 is configured in an annular shape and has an engaging recess (not shown) on its outer circumferential surface. The inner circumferential portion of the inner diameter side member 102 is spline-engaged with the second engaging portion 27 of the cylindrical portion 24, thereby preventing relative rotation with respect to the cylindrical portion 24. The inner diameter side member 102 is clamped from both axial sides by two retaining rings 104a, 104b that are engaged with the engaging grooves 33a, 33b of the cylindrical portion 24, thereby preventing axial displacement with respect to the cylindrical portion 24.

[0151] The engagement pin is detachably bridged between the outer diameter side member 101 and the inner diameter side member 102. In this example, the engagement pin protrudes radially inward from the inner peripheral surface of the outer diameter side member 101 and is supported in a state in which it is given an elastic force directed radially inward. The tip of the engagement pin is engageable with an engagement recess of the inner diameter side member 102.

[0152] The select plate 103 has engagement holes (not shown) that open at multiple locations around the circumference of the side surface on the other axial side. The tip of a pin 80 provided on the drive cam 62 is fitted into each engagement hole. This allows the select plate 103 to rotate integrally with the drive cam 62 (in the same direction and at the same speed).

[0153] The select plate 103 has a mode select portion which is a concave and convex portion in the circumferential direction.

[0154] The engagement device 8 switches between a state in which the outer diameter side member 101 and the inner diameter side member 102 are rotatable relative to each other and a state in which they are not, based on the rotation of the select plate 103. That is, based on the rotation of the select plate 103, the convex portion constituting the mode select portion pushes the engagement pin radially outward, thereby disengaging the engagement pin from the engagement concave portion, and switching the engagement device 8 to the cutting mode. This allows rotation of the inner diameter side member 102 relative to the outer diameter side member 101, and allows rotation of the rotating member 6 relative to the fixed portion 72.

[0155] In response to this, the convex portion constituting the mode select portion is moved to a position circumferentially displaced from the tip of the engagement pin based on the rotation of the select plate 103, thereby engaging the engagement pin with the engagement recess, thereby switching the engagement device 8 to the connection mode. This prevents rotation of the inner diameter side member 102 relative to the outer diameter side member 101, and prevents rotation of the rotating member 6 relative to the fixed part 72.

[0156] In this example, the planetary reduction mechanism 9 is composed of a planetary gear mechanism in which a planetary element 108 composed of a planetary gear is engaged, i.e., meshed, with a sun element 105 composed of a sun gear and a ring element 106 composed of a ring gear so as to be able to transmit torque.

[0157] The sun element 105 is connected to the input member 4 so as to be able to transmit torque, and is rotatable integrally with the input member 4. In this example, the sun element 105 is provided integrally on the outer peripheral surface of the end portion on the other axial side of the input member 4.

[0158] The ring element 106 is disposed coaxially around the sun element 105, and is connected to the rotating member 6 so as to be capable of transmitting torque, thereby being rotatable integrally with the rotating member 6. In this example, the ring element 106 is provided on an annular member 109 that is fixedly coupled to the rotating member 6. The annular member 109 has a small-diameter cylindrical portion 110 that is fitted and fixed to one axial end of the rotating member 6, a hollow circular plate-shaped connecting plate portion 111 that extends radially outward from one axial end of the small-diameter cylindrical portion 110, and a large-diameter cylindrical portion 112 that extends axially from the radially outer end of the connecting plate portion 111. The ring element 106 is provided integrally on the inner circumferential surface of the large-diameter cylindrical portion 112.

[0159] The carrier 107 is disposed coaxially with the sun element 105 and the ring element 106, between the sun element 105 and the ring element 106 in the radial direction, and is connected to the output member 5 so as to be able to transmit torque, and is rotatable integrally with the output member 5. In this example, the carrier 107 is provided integrally with the output member 5 at the other axial end of the output member 5.

[0160] Each of the plurality of planetary elements 108 is meshed with the sun element 105 and the ring element 106, and is supported by the carrier 107 so as to be rotatable (spinning) around its own central axis.

[0161] The two-speed transmission 1 of this example can switch between a low reduction ratio mode in which the reduction ratio between the input member 4 and the output member 5 is small (reduction ratio is 1), and a high reduction ratio mode in which the reduction ratio is larger than that in the low reduction ratio mode, by controlling the supply of electricity to the electric motor 98 and adjusting the rotational phase of the drive cam 62 to switch between the mode of the friction clutch device 7 and the mode of the engagement device 8.

[0162] <Low reduction ratio mode> To switch the two-speed transmission 1 to the low reduction ratio mode, the friction clutch device 7 is switched to the connection mode, and the engagement device 8 is switched to the disconnection mode.

[0163] Specifically, as shown in Figure 2(a), when the electric motor 98 is energized, the drive cam 62 is rotated in a direction that reduces the amount of the rolling elements 64 that climb up from the bottom of the recess 65a that constitutes the drive cam surface 65. This switches the friction clutch device 7 to the connection mode, so that the input member 4, which is connected and fixed to the first member 43, and the rotating member 6, which is the second member, rotate integrally. As a result, the sun element 105 and the ring element 106 rotate integrally.

[0164] Furthermore, by adjusting the rotation phase of the select plate 103 in accordance with the rotation of the drive cam 62, the engagement device 8 is switched to the disconnection mode, thereby allowing the rotation member 6 to rotate relative to the fixed part 72. As a result, the rotation of the ring element 106 relative to the fixed part 72 is allowed.

[0165] In this low reduction ratio mode, the sun element 105, ring element 106, and carrier 107 rotate in the same direction and at the same speed, and the entire planetary reduction mechanism 9 rotates as a unit, in a so-called glued state. Therefore, the rotational torque of the input member 4 is transmitted to the output member 5 as is, without being increased (decelerated), through the path shown by the thick line in Figure 2(a). In other words, in the low reduction ratio mode, the reduction ratio between the input member 4 and the output member 5 is 1.

[0166] <High reduction ratio mode> To switch the two-speed transmission 1 to the high reduction ratio mode, the friction clutch device 7 is switched to the disengagement mode, and the engagement device 8 is switched to the engagement mode.

[0167] Specifically, as shown in Figure 2(b), when the electric motor 98 is energized, the drive cam 62 is rotated in a direction that increases the amount by which the rolling elements 64 climb over the bottom of the recess that forms the drive cam surface 65. This switches the friction clutch device 7 to a disengagement mode, allowing relative rotation between the input member 4 coupled and fixed to the first member 43 and the rotating member 6, which is the second member. As a result, the sun element 105 and the ring element 106 become relatively rotatable.

[0168] Furthermore, by adjusting the rotation phase of the select plate 103 in accordance with the rotation of the drive cam 62, the engagement device 8 is switched to the connection mode, thereby preventing the rotation member 6 from rotating relative to the fixed part 72. As a result, the rotation of the ring element 106 relative to the fixed part 72 is prevented.

[0169] In such a high reduction ratio mode, the rotational torque of the input member 4 is transmitted to the output member 5 via the path shown by the thick line in Figure 2(b), namely, the input member 4, the sun element 105, the rotational motion of the planetary elements 108, the orbital motion of the planetary elements 108 based on the meshing with the ring element 106, and the path passing through the carrier 107.

[0170] In the high reduction ratio mode, the rotational torque of the input member 4 is increased by the planetary reduction mechanism 9 and transmitted to the output member 5. Note that the reduction ratio between the input member 4 and the output member 5 in the high reduction ratio mode is determined by the gear ratio between the ring element 106 and the sun element 105 (number of teeth of the ring element 106 / number of teeth of the sun element 105).

[0171] Two-speed transmission 1 can switch the reduction ratio between input member 4 and output member 5 between two levels, high and low, by switching the mode of friction clutch device 7 and the mode of engagement device 8. Specifically, in the region where the rotational torque input to input member 4 is low speed and high torque, two-speed transmission 1 switches to high reduction ratio mode, and in the region where the rotational torque input to input member 4 is high speed and low torque, two-speed transmission 1 switches to low reduction ratio mode. This makes it possible to make the acceleration performance and high-speed performance of electric vehicles and hybrid vehicles running using only an electric motor as a drive source similar to that of gasoline engine vehicles.

[0172] Alternatively, the planetary reduction mechanism 9 can be configured as a planetary roller mechanism in which a planetary element formed by a planetary roller is engaged, i.e., in rolling contact, with a sun element formed by a sun roller and a ring element formed by a ring roller so as to be able to transmit torque.

[0173] The sun element may be torque-transmittingly connected to the rotating member, the carrier may be torque-transmittingly connected to one of the input member and the output member, and the ring element may be torque-transmittingly connected to the other of the input member and the output member.

[0174] In the two-speed transmission 1 of this example, the clutch hub 15 of this example is applied, so that the amount of lubricating oil supplied to both the friction engagement portion 46 and the engagement device 8, which are two different components that engage with the clutch hub 15, is appropriately ensured, thereby making it possible to improve their durability.

[0175] [Example 2] A second example of the embodiment of the present disclosure will be described with reference to FIGS. 12(a) and 12(b).

[0176] This example differs from the first example in that a so-called normally open type clutch is used as the configuration of the friction clutch device 7a.

[0177] In the friction clutch device 7a of this example, the cam device 60a is disposed on one axial side of the friction engagement portion 46. Between the driven cam 63 of the cam device 60a and the friction plate located furthest on the one axial side out of the first friction plates 55 and the second friction plates 56 (out of the plurality of first friction plates 55 and the plurality of second friction plates 56), an elastic member 48a and a thrust rolling bearing 89a are sandwiched in this order from the one axial side.

[0178] The elastic member 48a elastically biases the friction clutch device 7a and the driven cam 63 in directions away from each other in the axial direction. The elastic member 48a is made up of a plurality of disc springs, compression coil springs, etc. In this example, the elastic member 48a is made up of a plurality of disc springs.

[0179] The friction clutch device 7a includes a return spring 118 that separates the first friction plates 55 and the second friction plates 56 from each other and elastically urges the first friction plates 55 and the second friction plates 56 in a direction to release the force pressing the first friction plates 55 and the second friction plates 56 against each other. In this example, the return spring 118 is stretched between the friction plate located furthest on one axial side and the friction plate located furthest on the other axial side among the first friction plates 55 and the second friction plates 56 (among the plurality of first friction plates 55 and the plurality of second friction plates 56), and elastically urges the friction plate located furthest on one axial side and the friction plate located furthest on the other axial side in directions away from each other.

[0180] In this example, when the friction clutch device 7a is switched to a disconnection mode in which torque is not transmitted between the rotating member 6 and the input member 4, the electric actuator 61 rotates the drive cam 62, thereby moving the driven cam 63 in a direction that reduces the axial distance between the drive cam 62 and the driven cam 63. This causes the force pressing the first friction plate 55 and the second friction plate 56 against each other to be lost. As a result, the return spring 118 acts to widen the distance between the first friction plate 55 and the second friction plate 56, disengaging the friction engagement portion 46 and switching the friction clutch device 7a to the disconnection mode.

[0181] On the other hand, when the friction clutch device 7a is switched to a connection mode in which torque is transmitted between the rotating member 6 and the input member 4, the electric actuator 61 rotates the drive cam 62, thereby moving the driven cam 63 in a direction in which the axial distance between the drive cam 62 and the driven cam 63 increases. This causes the driven cam 63 to press the first friction plates 55 and the second friction plates 56 against each other via the elastic member 48a and the thrust rolling bearing 89a. As a result, the first friction plates 55 and the second friction plates 56 press against each other, and the friction engagement portion 46 is engaged, thereby switching the friction clutch device 7a to the connection mode.

[0182] In this example, when the friction clutch device 7a is to be maintained in the connected mode, it is necessary to continue to supply current to the electric actuator 61. On the other hand, when the friction clutch device 7a is to be maintained in the disconnected mode, it is not necessary to continue to supply current to the electric actuator 61.

[0183] The other configurations and effects of the second example are the same as those of the first example.

[0184] [Example 3] A third example of the embodiment of the present disclosure will be described with reference to FIGS. 13 to 15(b).

[0185] In this example, the cylindrical portion 24a constituting the clutch hub 15a has a circumferential convex wall portion 36a on its inner peripheral surface between the one-side uneven portion 34a and the other-side uneven portion 35a, and has a circumferential groove 37a around the entire circumference in an axially intermediate portion of the inner peripheral surface of the circumferential convex wall portion 36a. In this example, the other axial end of the convex portion 39 of the one-side uneven portion 34a is continuous with the one axial end of the circumferential convex wall portion 36a (the radially inner surface of the convex portion 39 and the radially inner surface of the circumferential convex wall portion 36a are smoothly continuous without any steps), and the other axial end of the concave portion 38 of the one-side uneven portion 34a is closed by the side surface of the one axial side of the circumferential convex wall portion 36a. In addition, the end on one axial side of the convex portion 41 of the other-side uneven portion 35a is continuous with the end on the other axial side of the circumferential convex wall portion 36a (the radial inner surface of the convex portion 41 and the radial inner surface of the circumferential convex wall portion 36a are smoothly continuous without any steps), and the end on one axial side of the concave portion 40 of the other-side uneven portion 35a is blocked by the end face on the other axial side of the circumferential convex wall portion 36a.

[0186] In this example, the circumferential groove 37a has a cross-sectional shape of a concave arc, the deepest part of which is in the axial center.

[0187] In this example, the damming surface 29a is constituted by a surface of the inner surface of the circumferential groove 37a facing one axial side and a side surface of the circumferential protruding wall portion 36a on one axial side. That is, for the lubricating oil flowing in the other axial direction through the recesses 38 of the one-side uneven portion 34a, the side surface on one axial side of the circumferential protruding wall portion 36a that closes the end portion on the other axial side of the recesses 38 functions as the damming surface 29a. Also, for the lubricating oil flowing in the other axial direction through the protrusions 39 of the one-side uneven portion 34a, the surface of the inner surface of the circumferential groove 37a facing one axial side functions as the damming surface 29a.

[0188] In the structure of this example, on the inner surface of the cylindrical portion 24a that constitutes the clutch hub 15a, of the lubricating oil supplied to one axial side of the blocking surface 29a, the lubricating oil that enters the recesses 38 that constitute the one-side uneven portion 34a and moves to the other axial side is blocked by the side surface of the blocking surface 29a on one axial side of the circumferential convex wall portion 36a, and is thereby prevented from moving further in the other axial direction.

[0189] Furthermore, on the inner peripheral surface of the cylindrical portion 24a, of the lubricating oil supplied to one axial side of the damming surface 29a, the lubricating oil that moves along the radial inner surface of the convex portion 39 that constitutes the one-side uneven portion 34a to the other axial side enters the circumferential groove 37a and is blocked by the surface of the damming surface 29a, which is on the inner surface of the circumferential groove 37a facing one axial side, thereby preventing the lubricating oil from moving further in the other axial direction.

[0190] The other configurations and effects of the third example are the same as those of the first example.

[0191] [Example 4] A fourth example of the embodiment of the present disclosure will be described with reference to Fig. 16. This example is a modification of the first example.

[0192] In the cylindrical portion 24b constituting the clutch hub 15b of this example, of the recesses 38, 38a of the one-side uneven portion 34b, only some of the recesses 38 in the circumferential direction are formed with the circumferential convex wall portion 36b, and the damming surface 29 is disposed. In at least one of the recesses 38, 38a of the one-side uneven portion 34b and the recesses 40, 40a of the other-side uneven portion 35b, the circumferential convex wall portion 36b and the circumferential groove 37 are not disposed, and the recesses 38a and the recesses 40a are configured to be continuous with the same inner diameter.

[0193] Because circumferential groove pieces 117 are formed at the other axial end of all of the convex portions 39 of the one-side uneven portion 34b, the damming surfaces 29 are arranged in all of the convex portions 39 of the one-side uneven portion 34b. Because circumferential convex wall portions 36b are formed at the other axial end of some of the circumferential recesses 38 of the one-side uneven portion 34b, the damming surfaces 29 are arranged in all of the recesses 38. However, at least one recess 38a, 40a does not have a circumferential convex wall portion 36b, and therefore the damming surfaces 29 are not arranged for the recesses 38a of the one-side uneven portion 34b. In this example, oil holes 28 are not arranged in the recesses 38a where the damming surfaces 29 are not formed, and oil holes 28 are arranged only in the recesses 38 where the damming surfaces 29 are formed.

[0194] The lubricating oil flowing through the recess 38a to the other axial side flows out radially outward via the recess 40a and the end portion and end face on the other axial side of the cylindrical portion 24. The number and arrangement of the oil holes 28 and the recesses 38a, 40a that do not have the damming surface 29 are determined appropriately depending on the degree to which the amount of lubricating oil flowing out radially outward through the oil holes 28 and the amount of lubricating oil flowing out radially outward through the end portion and end face on the other axial side of the cylindrical portion 24 are adjusted. In this example, of the 32 recesses 38, 38a, 40, 40a present in the circumferential direction, the recesses 38a, 40a are provided at equal intervals in four locations in the circumferential direction.

[0195] The other configurations and effects of the fourth example are the same as those of the first example.

[0196] [Example 5] A fifth example of the embodiment of the present disclosure will be described with reference to FIGS.

[0197] In this example, the cylindrical portion 24c constituting the clutch hub 15c has a circumferential ridge 113 at the axially intermediate portion of the inner peripheral surface over the entire circumference.

[0198] In this example, the circumferential protrusion 113 is formed around the entire axial middle portion of the inner surface of the tubular portion 24c, more specifically, in a portion of the inner surface of the tubular portion 24c that radially overlaps with the locking groove 33a on one axial side of the two locking grooves 33a, 33b provided on the outer surface of the tubular portion 24c.

[0199] In this example, the circumferential ridge 113 has a rectangular cross-sectional shape.

[0200] In this example, the blocking surface 29b is formed by a side surface of the circumferential protrusion 113 on one axial side.

[0201] In this example, the portion of the inner peripheral surface of the cylindrical portion 24c that is axially deviated from the circumferential ridge 113 is configured as a cylindrical surface whose inner diameter does not change along the axial direction.

[0202] In the structure of this example, on the inner surface of the cylindrical portion 24c that constitutes the clutch hub 15c, lubricating oil supplied to one axial side of the blocking surface 29b is blocked by the blocking surface 29b, which is the side surface on one axial side of the circumferential protrusion 113, and is prevented from moving further in the other axial direction.

[0203] The other configurations and effects of the fifth example are the same as those of the first example.

[0204] [Example 6] A sixth example of the embodiment of the present disclosure will be described with reference to FIGS.

[0205] In this example, the cylindrical portion 24d that constitutes the clutch hub 15d is formed by combining a cylindrical portion main body 114 and a ring-shaped member 115.

[0206] The cylindrical body 114 has a locking groove 116 formed around the entire periphery at the axially intermediate portion of the inner circumferential surface.

[0207] The ring-shaped member 115 has its radially outer portion locked in the locking groove 116. In this example, the portion of the ring-shaped member 115 that protrudes radially inward from the locking groove 116 forms a circumferential protrusion 113a.

[0208] In this example, ring-shaped member 115 has a circular ring shape that is connected all around when viewed in the axial direction. In this example, ring-shaped member 115 is configured as a spiral retaining ring, which is a retaining ring made by winding a material in a spiral shape one or more times (for example, about two times).

[0209] In this example, the blocking surface 29c is formed by a side surface on one axial side of the circumferential protrusion 113a.

[0210] In the structure of this example, on the inner surface of the cylindrical portion 24d that constitutes the clutch hub 15d, lubricating oil supplied to one axial side of the damming surface 29c is blocked by the damming surface 29c, thereby preventing it from moving further in the other axial direction.

[0211] The other configurations and effects of the sixth example are the same as those of the first example.

[0212] When implementing the clutch hub or two-speed transmission according to one aspect of the present disclosure, the first to sixth examples of the embodiment can be combined as appropriate as long as no mutual contradictions arise.

[0213] For example, in the structure of the third example, at least one of the recesses of the one-side uneven portion and the other-side uneven portion may be configured so that the circumferential convex wall portion and the circumferential groove are not arranged, and the inner diameters of these recesses are continuous and the same. [Explanation of symbols]

[0214] 1 2-speed transmission 2. Drive source 3 Differential device 4 Input member 5 Output member 6 Rotating member (second member) 7, 7a Friction clutch device 8 Engagement device 9 Planetary reduction mechanism 10 Output shaft 11 Drive gear 12 Input gear 13 Output gear 14 Shaft member 15, 15a, 15b, 15c, 15d clutch hub 16 Large diameter cylinder 17 Medium diameter cylinder part 18 Small diameter cylinder part 19 Through hole 20 Locking groove 21 Protrusion 22 Mating surface part 23 Step surface 24, 24a, 24b, 24c, 24d cylindrical portion 25 Side plate part 26 First engagement portion 27 Second engagement portion 28 Oil hole 29, 29a, 29b, 29c Dammed surface 30 Male spline part 31 Recess 32 Convex part 33a, 33b locking groove 34, 34a, 34b One side uneven part 35, 35a, 35b Other side uneven part 36, 36a, 36b Convex wall in circumferential direction 37, 37a Circumferential groove 38, 38a recess 39 Convex part 40, 40a recess 41 Convex part 42 Through hole 43 First member 44 Retaining Ring 45 retaining ring 46 Friction engagement portion 47 Pressing plate 48 Elastic member 49 Pressing device 50 Large diameter cylinder 51 Small diameter cylinder part 52 Connection plate 53 Connecting member 54 Female spline part 55 1st friction plate 56 2nd friction plate 57 Retaining member 58 Circular part 59 Cylindrical part 60, 60a Cam device 61 Electric Actuator 62 Drive cam 63 Driven cam 64 rolling elements 65 Drive cam surface 65a Recess 65b Convex part 66 Support member 67 Bearing device 68 Radial bearing 69 Circular limbus 70 Cylindrical part 71 Mounting hole 72 Fixed part 73 Inner circle 74 outer ring 75 rolling elements 76 Inner Circle 77 Outer Ring 78 balls 79 Wheel Teeth 80-pin section 81 Rectangular hole 82a, 82b Support plate part 83a, 83b support hole 84 Female spline part 85 Male spline part 86 Support shaft Around 87 88 Pressing member 89 Thrust bearing 90 base 91 Pressing arm 92 Inner diameter side plate 93 Connecting tube 94 Outer diameter side plate part 95a, 95b Raceway ring 96 Rolling elements 97 Preloading member 98 Electric Motor 99 Reducer 100 Warm 101 outer diameter side member 102 Inner diameter side member 103 Select Plate 104a, 104b retaining ring 105 Sun Elements 106 Ring Elements 107 Career 108 Planetary Elements 109 Annular Member 110 Small diameter cylinder part 111 Connection plate part 112 Large diameter cylinder 113, 113a, 113b Circumferential protrusion 114 Cylindrical body 115 Ring-shaped member 116, 116a Locking groove 117 Circumferential groove piece 118 Return spring 200, 200a clutch hub 201, 201a cylindrical part 202, 202a Side plate part 203, 203a Male spline part 204, 204a oil hole 205, 205a recess 206, 206a convex part 207, 207a Uneven part 208 Weir

Claims

1. a cylindrical portion having a first engaging portion disposed on one axial side of the outer peripheral surface and engaging with a component constituting a friction clutch device, a second engaging portion disposed on the other axial side of the outer peripheral surface and engaging with a component constituting a device other than the friction clutch device, and oil holes passing radially through a plurality of locations within the same axial range as the first engaging portion; a side plate portion extending radially inward from one axial end of the cylindrical portion; Equipped with the cylindrical portion has a blocking surface facing one axial side in an axially intermediate portion of its inner circumferential surface that is located on the other axial side of the oil hole, and the inner diameter of the blocking surface is equal to or smaller than the inner diameter of a portion of the inner circumferential surface that is located on the one axial side of the blocking surface, The cylindrical portion is a one-side concave-convex portion formed by alternately arranging concave and convex portions in the circumferential direction and provided in a portion of the inner circumferential surface that radially overlaps with the first engaging portion; a second-side concave-convex portion formed by alternately arranging concave and convex portions in the circumferential direction and provided on the inner circumferential surface at a portion that radially overlaps with the second engaging portion; a circumferential convex wall portion formed on the inner circumferential surface at a portion adjacent to one axial side of the other-side concave-convex portion; a circumferential groove formed on the inner circumferential surface in a portion between the one-side concave-convex portion and the other-side concave-convex portion; a radially inner end of the oil hole opens into the recess of the one-side uneven portion, the blocking surface is configured by a surface of the inner surface of the circumferential groove facing one axial side and a side surface of the circumferential protruding wall portion on one axial side. Clutch hub.

2. the cylindrical portion has a male spline portion on the outer circumferential surface, the male spline portion having recessed portions and protruding portions alternately arranged in the circumferential direction, the first engagement portion is formed by a portion on one axial side of the male spline portion, and the second engagement portion is formed by a portion on the other axial side of the male spline portion, 2. The clutch hub according to claim 1.

3. The circumferential groove is formed at an end portion on the other axial side of the convex portion of the one-side concave-convex portion so as to circumferentially cross the end portion on the other axial side.

2. The clutch hub according to claim 1.

4. 4. The clutch hub according to claim 3, wherein the blocking surface is formed over the entire circumference.

5. 4. The clutch hub according to claim 3, wherein the blocking surfaces are disposed in only some of the recesses in the circumferential direction of the one-side uneven portion.

6. The circumferential groove is formed in an axially intermediate portion of the circumferential protruding wall portion.

2. The clutch hub according to claim 1.

7. 7. The clutch hub according to claim 6, wherein the blocking surface is formed over the entire periphery.

8. 7. The clutch hub according to claim 6, wherein the blocking surfaces are disposed in only some of the recesses in the circumferential direction of the one-side uneven portion.

9. an input member rotatably supported relative to a fixed portion that does not rotate even during use; an output member supported coaxially with the input member and capable of rotating relative to the input member; a rotating member supported coaxially with the input member and the output member and capable of rotating relative to the input member and the output member; a friction engagement portion having a first friction plate and a second friction plate supported to allow relative axial displacement, the friction engagement portion being provided between the input member or the output member and the rotating member, the friction engagement portion pressing the first friction plate and the second friction plate against each other to switch the input member or the output member and the rotating member to a state in which they rotate integrally, and releasing the force pressing the first friction plate and the second friction plate against each other to switch the input member or the output member and the rotating member to a state in which they rotate relatively; an engagement device provided between the fixed portion and the rotating member, which switches the rotating member between a rotatable state and a non-rotatable state relative to the fixed portion; a planetary reduction mechanism including a sun element, a ring element disposed around the sun element, a carrier disposed between the sun element and the ring element in the radial direction, and a plurality of planetary elements rotatably supported by the carrier and engaged with the sun element and the ring element to enable torque transmission; Equipped with an input element, which is any one of the sun element, the ring element, and the carrier, is connected to the input member so as to rotate integrally with the input member; an output element, which is one of the sun element, the ring element, and the carrier and is an element separate from the input element, is connected to the output member so as to rotate integrally with the output member; Rotating elements, which are the remaining elements of the sun element, the ring element, and the carrier excluding the input element and the output element, are connected to the rotating member so as to rotate integrally with the rotating member, The rotating member includes a clutch hub according to any one of claims 1 to 8, the first friction plate or the second friction plate engages with the first engagement portion of the cylindrical portion, a component constituting the engagement device is engaged with the second engagement portion of the cylindrical portion; Two-speed transmission.

Images