transmission device

Abstract

A variable speed device is provided which suppresses deformation of a drum member. The drum member, which is a press processed product, has a drum portion functioning as a first clutch drum of a first clutch on one side in an axial direction and a hub portion functioning as a second clutch hub of a second clutch on the other side in the axial direction; and a support member which is engaged to an inner periphery between the drum portion and the hub portion of the drum member in the axial direction via a joint portion and has an annular wall portion. Further, the first clutch has a first clutch hub, the drum portion, a plurality of first friction engagement pieces, a plurality of second friction engagement pieces, and a first piston, and the second clutch has the hub portion, a second clutch drum, a plurality of third friction engagement pieces, a plurality of fourth friction engagement pieces, and a second piston.

Description

Technical Field

[0001] This application relates to a speed change device. Background Technology

[0002] Conventionally, a transmission device of this type has been proposed that includes: a drum member having a drum portion at one axial end that functions as a clutch drum and a hub portion at the central axial portion that functions as a brake hub; and a support member fixed to the inner circumference of the other axial end of the drum portion and having an annular wall portion (see, for example, Patent Document 1). In this transmission device, the clutch, in addition to the drum portion, also includes a clutch hub, friction plates, a piston, etc. Furthermore, the outer circumference of the piston is fitted into the inner circumference of the hub portion and supported by the hub portion. The brake, in addition to the hub portion, also includes a brake drum (housing), friction plates, a piston, etc.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2006-322602

[0004] In the aforementioned transmission device, the support member is fixed to the axial end of the drum member. Therefore, the deviation between the fixed positions of the drum member and the support member and the center of gravity of the drum member along the axial direction of the transmission device is prone to increase. In order to suppress deformation of the drum member even when it rotates at high speed, the thickness of the drum member plate must be increased in advance to ensure high rigidity. Thus, there is still room for further improvement in miniaturization and weight reduction in the aforementioned transmission device. Summary of the Invention

[0005] The main purpose of the speed change device in this application is to suppress the deformation of the drum component.

[0006] To achieve the aforementioned main objectives, the speed change device of this application employs the following means.

[0007] The purpose of this application is to provide a speed change device that includes:

[0008] A first clutch includes a first clutch hub, a first clutch drum, a plurality of first friction engagement plates fitted into the first clutch hub, a plurality of second friction engagement plates alternately fitted into the first clutch drum, and a first piston that frictionally engages the first friction engagement plates and the second friction engagement plates; and

[0009] The second clutch includes a second clutch hub, a second clutch drum, a plurality of third friction engagement plates fitted into the second clutch hub, a plurality of fourth friction engagement plates fitted into the second clutch drum alternately with the third friction engagement plates, and a second piston that frictionally engages the third friction engagement plates and the fourth friction engagement plates.

[0010] The transmission device includes:

[0011] The drum component, being a stamped product, has a drum portion on one side in the axial direction that functions as the first clutch drum and a hub portion on the other side in the axial direction that functions as the second clutch hub; and

[0012] A support member, connected via a joint to the inner circumference of the drum portion and the hub portion of the drum member in the axial direction, and having an annular wall portion.

[0013] The transmission device of this application includes: a drum member, which is a stamped product, having a drum portion on one side in the axial direction that functions as a first clutch drum and a hub portion on the other side in the axial direction that functions as a second clutch hub; and a support member, which is joined to the inner circumference between the drum portion and the hub portion of the drum member in the axial direction via a joint and has an annular wall portion. Therefore, the drum member is fixed between the drum portion and the hub portion in the axial direction by the support member, thereby reducing the axial deviation between the fixed position of the drum member and the support member and the center of gravity of the drum member. This suppresses deformation of the drum member during high rotation without requiring high rigidity, and miniaturization and weight reduction can be achieved by making the drum member with a relatively thin sheet thickness. Furthermore, the drum member can be formed by stamping, thus increasing the radial freedom of formation and reducing costs compared to integrally forming the drum member and support member by cutting or spinning. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the power transmission device 10 of this application.

[0015] Figure 2 This is an action table that shows the relationship between the various gears of the automatic transmission 20 and the operating states of the clutches C1 to C4 and the brakes B1 and B2.

[0016] Figure 3 This is an enlarged sectional view showing the main parts of the power transmission device 10. The figure shows the periphery of the clutches C3 and C4 of the automatic transmission 20 of the power transmission device 10.

[0017] Figure 4 This is an enlarged sectional view of the main part of the automatic transmission 20B, which represents the comparison method.

[0018] Figure 5 This is a process diagram illustrating an example of the manufacturing process of the integral component consisting of drum member 30 and support member 31.

[0019] The reference numerals in the attached figures are explained as follows:

[0020] 10: Power transmission device; 11: Gearbox; 12: Starting device; 13: Front cover; 14o: One-way clutch; 14p: Pump wheel; 14s: Guide wheel; 14t: Turbine; 15: Lock-up clutch; 16: Shock absorption mechanism; 17: Oil pump; 18: Chain; 20, 20B: Automatic transmission; 20i: Input shaft; 20o: Output shaft; 21: First planetary gear mechanism; 21c: Planetary gear carrier; 21pa: Pinion; 21r: Ring gear; 21s: Sun gear; 25: First planetary gear mechanism. 2. Planetary gear mechanism, 25c: planetary gear carrier, 25pa: pinion, 25pb: pinion, 25r: gear ring, 25sa: first sun gear, 25sb: second sun gear, 30: drum component, 31: support component, 32: clutch hub, 32s: spline, 34: piston, 34b: brake backing plate, 34f: friction plate, 34s: release plate, 35: piston, 36: engagement oil chamber, 37: release chamber dividing and forming component, 38: centrifugal hydraulic release chamber, 39: 41: Return spring; 42: Clutch drum; 44b: Connecting member; 44f: Brake backing plate; 44s: Friction plate; 45: Separator plate; 46: Piston; 47: Engagement oil chamber; 48: Release chamber dividing member; 49: Centrifugal hydraulic release chamber; 50: Return spring; 60: Speed ​​sensor; 61: Drum member; 300: Support member; 300: Drum portion; 300s: Spline; 301: Outer wall portion; 302: Cylindrical portion; 303: Inner wall portion; 304: Hub portion; 304s: Spline... Key, 310: Inner cylinder part, 311: Annular wall part, 312: Outer cylinder part, 410: Cylindrical part, 410s: Spline, 411: Annular wall part, 420: Inner cylinder part, 421: Annular wall part, 422: Outer cylinder part, 600: Drum part, 601: Outer wall part, 602: Hub part, 603: Inner wall part, 604: Cylindrical part, 610: Inner cylinder part, 611: Inner wall part, 612: Outer cylinder part, 613: Outer wall part, B1, B2: Brake, C1~C4: Clutch. Detailed Implementation

[0021] Below, refer to the appendix. Figure 1 The following describes the methods used to implement the present invention.

[0022] Figure 1 This is a schematic diagram of the power transmission device 10 of this application. Figure 1The power transmission device 10 shown is a device that connects to the crankshaft of an engine (internal combustion engine, not shown) and / or the rotor of an electric motor, which is a drive source mounted longitudinally at the front of a rear-wheel drive vehicle, and is capable of transmitting power (torque) from the engine, etc., to the left and right rear wheels (drive wheels, not shown). As shown, the power transmission device 10 includes a gearbox (stationary member) 11, a starting device (fluid transmission device) 12, an oil pump 17, an automatic transmission 20 that changes the speed of the power transmitted from the engine, etc., to the input shaft (input member) 20i and transmits it to the output shaft (output member) 20o, etc.

[0023] The starting device 12 includes a hydraulic torque converter (fluid transmission device) having: a front cover 13 connected to the crankshaft of an engine and / or the rotor of an electric motor via a drive plate (not shown); a pump impeller 14p having an input side tightly fixed to a pump housing of the front cover 13; a turbine 14t on the output side connected to the input shaft 20i of the automatic transmission 20; a guide wheel 14s disposed inside the pump impeller 14p and the turbine 14t and rectifying the flow of actuating oil ATF from the turbine 14t to the pump impeller 14p; and a one-way clutch 14o that restricts the rotation direction of the guide wheel 14s to one direction. Alternatively, the starting device 12 may also be a device having a hydraulic coupling without the guide wheel 14s.

[0024] Furthermore, the starting device 12 includes: a lock-up clutch 15 that connects the front cover 13, which is connected to the crankshaft of the engine, and the input shaft 20i of the automatic transmission 20, and can disconnect the connection between them; and a damping mechanism 16 that dampens vibrations between the front cover 13 and the input shaft 20i of the automatic transmission 20. In this embodiment, the lock-up clutch 15 is configured as a multi-plate friction hydraulic clutch, which has multiple friction engagement plates (friction plates and release plates). However, the lock-up clutch 15 may also be a single-plate friction hydraulic clutch.

[0025] The oil pump 17 includes: a rotor connected to the pump wheel 14p of the starting device 12 via a chain 18; an external gear (drive gear) having multiple external teeth and rotating integrally with the rotor; and an internal gear (driven gear) having multiple internal teeth that mesh with the external teeth of the external gear and have one more internal tooth than the total number of external teeth, and being eccentrically arranged relative to the external gear. The oil pump 17 is driven by power from the engine transmitted via the chain 18, etc., and draws working oil stored in an oil pan (not shown) and pumps it to an oil pressure control device (not shown).

[0026] The automatic transmission 20 is configured as an 8-speed transmission, such as... Figure 1As shown, in addition to the input shaft 20i, the output shaft 20o connected to the left and right rear wheels via a differential gear (not shown), and the drive shaft, the automatic transmission 20 also includes a first planetary gear mechanism 21 and a second planetary gear mechanism 25 arranged side-by-side in the axial direction of the automatic transmission 20 (input shaft 20i, output shaft 20o). The first planetary gear mechanism 21 is a double-pinion planetary gear. The second planetary gear mechanism 25 is a Lavigno-type planetary gear mechanism (compound planetary gear mechanism) that combines a double-pinion planetary gear and a single-pinion planetary gear. Furthermore, the automatic transmission 20 includes four clutches C1 to C4 and brakes B1 and B2 for changing the power transmission path from the input shaft 20i to the output shaft 20o.

[0027] The first planetary gear mechanism 21 and the second planetary gear mechanism 25 are located from the starting device 12, i.e., the engine side. Figure 1 Starting from the left side of the transmission, the first planetary gear mechanism 21 and the second planetary gear mechanism 25 are arranged in the transmission 11 in that order, i.e., the first planetary gear mechanism 21, the single-pinion planetary gear mechanism constituting the second planetary gear mechanism 25, and the double-pinion planetary gear mechanism constituting the second planetary gear mechanism 25. Thus, the first planetary gear mechanism 21 is positioned close to the starting device 12 at the front of the vehicle. The second planetary gear mechanism 25 is positioned close to the output shaft 20o at the rear of the vehicle.

[0028] The first planetary gear mechanism 21 includes: a sun gear 21s as an external gear; a ring gear 21r as an internal gear, arranged on a circle concentric with the sun gear 21s; and a planetary gear carrier 21c that holds multiple sets of two pinions 21pa and 21pb together, allowing them to rotate freely on their own axis and revolve freely around the sun gear 21s, wherein the two pinions 21pa and 21pb are kept meshed with each other, with one meshing with the sun gear 21s and the other with the ring gear 21r. Figure 1 As shown, the sun gear 21s of the first planetary gear mechanism 21 is fixed to the gearbox 11. The planet carrier 21c of the first planetary gear mechanism 21 is connected to the input shaft 20i and rotates integrally with the input shaft 20i. The first planetary gear mechanism 21 functions as a reduction gear, reducing the power transmitted to the planet carrier 21c, which is the input element, and outputting it from the ring gear 21r, which is the output element.

[0029] The second planetary gear mechanism 25 includes: a first sun gear 25sa and a second sun gear 25sb as external gears; a ring gear 25r as an internal gear, arranged on a circle concentric with the first and second sun gears 25sa and 25sb; a plurality of pinions 25pa meshing with the first sun gear 25sa; a plurality of long pinions 25pb meshing with the second sun gear 25sb and the plurality of pinions 25pa, and meshing with the ring gear 25r; and a planetary gear carrier 25c holding the plurality of pinions 25pa and the plurality of long pinions 25pb so that they can rotate freely on their own axis and revolve freely around the sun. The ring gear 25r of the second planetary gear mechanism 25 is connected to the output shaft 20o and rotates integrally with the output shaft 20o.

[0030] Clutch C1 is a component capable of connecting and disconnecting the ring gear 21r of the first planetary gear mechanism 21 and the first sun gear 25sa of the second planetary gear mechanism 25. Clutch C2 is a component capable of connecting and disconnecting the input shaft 20i and the planet carrier 25c of the second planetary gear mechanism 25. Clutch C3 is a component capable of connecting and disconnecting the ring gear 21r of the first planetary gear mechanism 21 and the second sun gear 25sb of the second planetary gear mechanism 25. Clutch C4 is a component capable of connecting and disconnecting the planet carrier 21c of the first planetary gear mechanism 21 and the second sun gear 25sb of the second planetary gear mechanism 25.

[0031] Brake B1 is a component that fixes the second sun gear 25sb of the second planetary gear mechanism 25 to the gearbox (stationary member) 11 so that it cannot rotate relative to the gearbox (stationary member) 11, and is capable of releasing the fixation of the second sun gear 25sb relative to the gearbox 11. Brake B2 is a component that fixes the planetary gear carrier 25c of the second planetary gear mechanism 25 to the gearbox 11 so that it cannot rotate relative to the gearbox 11, and is capable of releasing the fixation of the planetary gear carrier 25c relative to the gearbox 11.

[0032] In this embodiment, clutches C1 to C4 are multi-plate friction hydraulic clutches (friction engagement elements), which have a hydraulic servo consisting of a piston, multiple friction engagement plates (friction plates and release plates), engagement oil chambers supplied with actuating oil, and a centrifugal hydraulic release chamber. Similarly, brakes B1 and B2 are multi-plate friction hydraulic brakes, which also have a hydraulic servo consisting of a piston, multiple friction engagement plates (friction plates and release plates), and engagement oil chambers supplied with actuating oil. Clutches C1 to C4 and brakes B1 and B2 are operated by supplying and discharging actuating oil via a hydraulic control device.

[0033] Figure 2 It is an action table that shows the relationship between the various gears of the automatic transmission 20 and the operating states of clutches C1 to C4, and brakes B1 and B2. Figure 2 The circle markings indicate clutch or brake engagement. Automatic transmission 20 converts clutches C1-C4 and brakes B1 and B2 into... Figure 2 The operation table shows the states to provide forward and reverse gears from 1st to 8th gear. Additionally, at least one of the clutches C1 to C4 and the brakes B1 and B2 can be an engaging element such as a claw clutch.

[0034] Figure 3 This is an enlarged sectional view showing the main parts of the power transmission device 10. Figure 3 This describes the peripheral structure of the clutches C3 and C4 in the automatic transmission 20 of the power transmission device 10. For example... Figure 3 As shown, clutches C3 and C4 are axially located from the starting device 12 side of the automatic transmission 20. Figure 3 Starting from the left side of the image, clutches C4 and C3 are arranged in that order. Clutch C3 can connect the ring gear 21r of the first planetary gear mechanism 21 and the second sun gear 25sb of the second planetary gear mechanism 25 to each other. Clutch C4 can connect the planetary gear carrier 21c of the first planetary gear mechanism 21 and the second sun gear 25sb of the second planetary gear mechanism 25 to each other.

[0035] Clutches C3 and C4 are connected to the second sun gear 25sb of the second planetary gear mechanism 25 as common connecting elements. Therefore, as Figure 3 As shown, clutches C3 and C4 share the second sun gear 25sb of the second planetary gear mechanism 25 (see reference). Figure 1 The drum component 30 is always connected (fixed) and functions as the clutch drum of clutch C3 and the clutch hub of clutch C4.

[0036] The drum component 30 is a stamped product formed by stamping. The drum component 30 includes: a cylindrical drum portion 300 extending axially in the automatic transmission 20; and an outer side wall portion 301 extending from one end of the drum portion 300. Figure 3 The drum 300 extends radially inward from its left end; a cylindrical portion 302 extends from the inner circumference of the outer wall portion 301 to the end opposite to the axially extending drum portion 300; an inner wall portion 303 extends radially inward from the end of the cylindrical portion 302 opposite to the outer wall portion 301; a cylindrical hub portion 304 extends from the inner circumference of the inner wall portion 303 to the side opposite to the axially extending cylindrical portion 302. A spline 300s is formed on the inner circumference of the drum portion 300. A spline 304s is formed on the outer circumference of the hub portion 304.

[0037] In addition to the drum portion 300 of the drum component 30, the clutch C3 also includes a support component 31, a clutch hub 32, multiple friction plates (first friction engagement plates) 34f, multiple separation plates (second friction engagement plates) 34s arranged alternately with the friction plates 34f, a brake backing plate 34b, a piston 35 that pushes the friction plates 34f and the separation plates 34s to make them frictionally engage, and a release chamber dividing and forming component 37.

[0038] The free end of the drum portion 300 of the drum component 30 ( Figure 3 The right end of the middle) is connected to the second sun gear 25sb of the second planetary gear mechanism 25 via a connecting member (see reference). Figure 1 The support member 31 has: a cylindrical inner cylinder portion 310 extending axially in the automatic transmission 20; and an annular wall portion 311 extending from one end of the inner cylinder portion 310. Figure 3 The outer cylindrical portion 312 extends radially outward from the left end of the inner cylindrical portion 310; it extends axially from the outer periphery of the annular wall portion 311 to the same side as the inner cylindrical portion 310. The outer cylindrical portion 312 is shorter than the inner cylindrical portion 310. The outer periphery of the outer cylindrical portion 312 is fixed to the inner periphery of the cylindrical portion 302 of the drum member 30 (between the drum portion 300 and the hub portion 304 in the axial direction) by welding. That is, the outer cylindrical portion 312 and the cylindrical portion 302 are connected (fixed) via a joint (welding portion).

[0039] The clutch hub 32 is integrally formed with the gear ring 21r of the first planetary gear mechanism 21 and is cylindrical. Splines 32s are formed on the outer peripheral surface of the clutch hub 32. Multiple friction plates 34f are annular members with friction material attached to both sides, and the inner peripheral portion of the multiple friction plates 34f is fitted into the splines 32s of the clutch hub 32. Multiple release plates 34s are annular members smoothly formed on both sides, and the outer peripheral portion of the multiple release plates 34s and the multiple friction plates 34f are alternately fitted into the splines 300s of the drum portion 300 of the drum member 30. The brake backing plate 34b can be connected to the part located furthest from the starting device 12 by its outer peripheral portion. Figure 3 The friction plate 34f (on the right side) is fitted into the spline 300s of the drum 300 by abutting. The brake base plate 34b is axially supported by a retaining ring mounted on the drum 300.

[0040] Piston 35 is positioned closer to the starting device 12 than friction plate 34f and separator plate 34s. Figure 3The piston 35 (left side) is supported by the outer peripheral surface of the inner cylinder portion 310 and the inner peripheral surface of the outer cylinder portion 312 of the support member 31, allowing it to move freely in the axial direction. Furthermore, the outer peripheral portion of the pressing part of the piston 35 engages with the spline 300s of the drum portion 300. Thus, the piston 35 is guided by the spline 300s of the drum portion 300. Sealing members are arranged between the outer peripheral surface of the piston 35 and the inner cylinder portion 310, and between the inner peripheral surface of the piston 35 and the outer cylinder portion 312. Thus, an engagement oil chamber 36 is formed between the piston 35 and the annular wall portion 311 of the support member 31, supplying operating oil (engagement oil pressure) for engaging the clutch C3. That is, the engagement oil chamber 36 is formed by the inner cylinder portion 310, the annular wall portion 311, the outer cylinder portion 312, and the piston 35 of the support member 31. In this embodiment, the engagement oil chamber 36 is formed radially inside the cylindrical portion 302 relative to the drum member 30.

[0041] The release chamber dividing forming member 37 is supported by the inner cylinder portion 310 and rotates integrally with the inner cylinder portion 310 of the support member 31. This release chamber dividing forming member 37, together with the piston 35, divides to form a centrifugal oil pressure release chamber 38 for releasing the centrifugal oil pressure generated within the engagement oil chamber 36. In this embodiment, the outer diameter of the cylindrical portion 302 of the drum member 30 is smaller than the outer diameter of this centrifugal oil pressure release chamber 38. A plurality of return springs 39 are arranged circumferentially spaced between the piston 35 and the release chamber dividing forming member 37 (within the centrifugal oil pressure release chamber 38). Helical springs can be used as return springs 39. The return springs 39 apply force in a manner that causes the piston 35 to move away from the friction plate 34f and the separation plate 34s.

[0042] In addition to the hub 304 of the drum member 30, the clutch C4 also includes a clutch drum 41, a connecting member 42, multiple friction plates (third friction engagement plates) 44f, multiple separation plates (fourth friction engagement plates) 44s arranged alternately with the friction plates 44f, a brake backing plate 44b, a piston 45 that pushes the friction plates 44f and the separation plates 44s to make them frictionally engage, and a release chamber dividing member 47.

[0043] The diameter of the hub 304 is smaller than the diameter of the clutch hub 32 of the clutch C3. The clutch drum 41 has: a cylindrical portion 410 extending axially along the automatic transmission 20; and an annular wall portion 411 extending from one end of the cylindrical portion 410. Figure 3 The cylindrical portion 410 extends radially inward from the left end of the clutch C3. The diameter of the cylindrical portion 410 is smaller than the diameter of the drum portion 300 of the clutch C3. Splines 410s are formed on the inner circumference of the cylindrical portion 410. Oil holes 410h are formed radially through the splines 410s of the cylindrical portion 410 at circumferential intervals. The connecting member 42 has: a cylindrical inner cylinder portion 420 extending axially; and an annular wall portion 421 extending from one end of the inner cylinder portion 420. Figure 3 The left end of the inner cylinder 420 extends radially outward; the cylindrical outer cylinder 422 extends axially from the outer periphery of the annular wall 421 to the same side as the inner cylinder 420. Figure 3 The right end of the inner cylinder 420 is connected to the planetary gear carrier 21c of the first planetary gear mechanism 21. The outer periphery of the inner cylinder 420 supports the inner periphery of the inner cylinder 310 of the support member 31 for free rotation. The outer periphery of the annular wall 421 is fixed to the inner periphery of the annular wall 411 of the clutch drum 41 by welding. That is, the annular wall 421 and the annular wall 411 are connected (fixed) via a joint (welding part). Therefore, the clutch drum 41 and the planetary gear carrier 21c of the first planetary gear mechanism 21 are connected via the connecting member 42. Moreover, the planetary gear carrier 21c of the first planetary gear mechanism 21 is connected to the input shaft 20i, so the input shaft 20i, the planetary gear carrier 21c of the first planetary gear mechanism 21, the connecting member 42, and the clutch drum 41 rotate as a whole.

[0044] The multiple friction plates 44f are annular members with friction material attached to both sides. The inner periphery of the multiple friction plates 44f is fitted into the splines 304s of the hub portion 304 of the drum member 30. The multiple separation plates 44s are annular members smoothly formed on both sides. The outer periphery of the multiple separation plates 44s, arranged alternately with the multiple friction plates 44f, is fitted into the splines 410s of the cylindrical portion 410 of the clutch drum 41. The brake backing plate 44b has its outer periphery capable of engaging with the part located furthest from the starting device 12. Figure 3 The friction plate 44f (on the right side) is fitted into the spline 410s of the cylindrical portion 410 by abutting. The brake base plate 44b is axially supported by a retaining ring installed on the cylindrical portion 410.

[0045] Piston 45 is located closer to the starting device 12 than friction plate 44f and separator plate 44s. Figure 3 The piston 45 (left side) is supported by the outer peripheral surfaces of the inner cylinder portion 420 and the outer cylinder portion 422 of the connecting member 42, allowing it to move freely in the axial direction. Furthermore, the outer peripheral portion of the pressing part of the piston 45 engages with the splines 410s of the cylindrical portion 410 of the clutch drum 41. Thus, the piston 45 is also guided by the splines 410s of the cylindrical portion 410. Sealing members are arranged between the piston 45 and the outer peripheral surfaces of the inner cylinder portion 420, and between the piston 45 and the outer peripheral surfaces of the outer cylinder portion 422. Thus, an engagement oil chamber 46 is formed between the piston 45 and the annular wall portion 421 of the connecting member 42, supplying operating oil (engagement oil pressure) for engaging the clutch C4. That is, the engagement oil chamber 46 is formed by the inner cylinder portion 420, the annular wall portion 421, the outer cylinder portion 422, and the piston 45 of the connecting member 42.

[0046] The release chamber dividing forming member 47 is supported by the inner cylinder portion 420 and rotates integrally with the inner cylinder portion 420 of the connecting member 42. This release chamber dividing forming member 47, together with the piston 45, divides to form a centrifugal oil pressure release chamber 48 for releasing the centrifugal oil pressure generated in the engagement oil chamber 46. Between the piston 45 and the release chamber dividing forming member 47 (within the centrifugal oil pressure release chamber 48), a plurality of return springs 49 are arranged at circumferential intervals. Helical springs can be used as return springs 49. The return springs 49 apply force in a manner that causes the piston 45 to disengage from the friction plate 44f and the separating plate 44s.

[0047] On the gearbox 11, at the opening end of the clutch drum 41 of the clutch C4 ( Figure 3 The right end of the cylinder 41, that is, the outer peripheral surface of the cylindrical portion 410 which is closer to the free end side than the oil hole 410h (the position where it does not overlap with the oil hole 410h in the axial direction when viewed radially), is provided with a speed sensor 50 for detecting the rotational speed of the clutch drum 41 in such a way that it overlaps in the axial direction with the welded portion of the cylindrical portion 302 of the drum member 30 and the outer cylindrical portion 312 of the support member 31 when viewed radially.

[0048] In addition, on the outer peripheral surface of the clutch drum 41, a plurality of recesses are formed at intervals in the circumferential direction, which serve as the detection portion of the speed sensor 50.

[0049] Figure 4 This is an enlarged sectional view of the main part of the automatic transmission 20B, which represents the comparison method. Figure 4 This diagram shows the configuration of the clutches Ca and Cb and the brake Ba periphery of the automatic transmission 20B. A brief explanation follows. Figure 4 As shown, the clutch Ca and the brake Ba share a drum component 60 that functions as the clutch drum of the clutch Ca and the brake hub of the brake Ba.

[0050] The drum component 60 is a stamped product formed by stamping. The drum component 60 includes: a cylindrical drum portion 600 extending axially in the automatic transmission 20B; and an outer side wall portion 601 extending from one end of the drum portion 600. Figure 4 The left end of the drum 601 extends radially inward; the cylindrical hub 602 extends axially from the inner circumference of the outer wall 601 to the end opposite to the drum 600; the inner wall 603 extends radially inward from the end of the hub 602 opposite to the outer wall 601; the cylindrical tubular portion 604 extends axially from the inner circumference of the inner wall 603 to the side opposite to the hub 602.

[0051] In addition to the drum portion 600 of the drum assembly 60, the clutch Ca also includes a support member 61, a clutch hub 62, multiple friction plates 64f fitted into the outer periphery of the clutch hub 62, multiple release plates 64s alternately arranged and fitted into the inner periphery of the drum portion 600, a brake backing plate, and a piston 65 that causes the friction plates 64f and the release plates 64s to engage in frictional contact. The outer periphery of the piston 65 is fitted into the inner periphery of the hub portion 602 of the drum assembly 60.

[0052] The support member 61 has: a cylindrical inner cylinder portion 610 extending axially along the automatic transmission 20; and an inner sidewall portion 611 extending from one end of the inner cylinder portion 610. Figure 4 The outer cylindrical portion 612 extends radially outward from the left end of the inner wall portion 611; the outer cylindrical portion 613 extends axially from the outer periphery of the inner wall portion 611 to the same side as the inner cylinder portion 610; the outer wall portion 613 extends radially outward from the opening end of the outer cylinder portion 612. Figure 4 The outer cylinder 612 is formed to be shorter than the inner cylinder 610. The outer periphery of the outer wall portion 613 is welded to the free end of the cylindrical portion 604 of the drum member 60. Figure 4 The left end of the tube is fixed. That is, the outer wall portion 613 and the cylindrical portion 604 are connected (fixed) via a joint (welding portion).

[0053] In addition to the hub 602 of the drum component 60, the brake Ba also includes a brake drum (gearbox) 71, multiple friction pads 74f that are fitted into the outer periphery of the hub 602, multiple separation pads 74s that are alternately fitted into the inner periphery of the brake drum 71 with the friction pads 74f, a brake backing plate, and a piston 75 that causes the friction pads 74f and the separation pads 74s to engage in frictional contact.

[0054] In the automatic transmission 20B of the comparative method, the inner periphery of the axial end of the drum member 60 and the outer periphery of the outer wall portion 613 of the support member 61 are fixed by welding. Therefore, the deviation between the fixed position of the drum member 60 and the support member 61 and the center of gravity of the drum member 60 in the axial direction of the automatic transmission 20 is prone to increase. Thus, there is a possibility that the drum member 60 may deform during high-speed rotation. In particular, in the automatic transmission 20B, the clutch Cb is configured to be radially inward than the drum member 60 and axially overlap with the brake Ba when viewed radially from the automatic transmission 20. Therefore, the axial length of the drum member 60 in the automatic transmission 20 is increased, thus making this deviation more likely to increase.

[0055] In this regard, in the automatic transmission 20 of the embodiment, the inner periphery of the cylindrical portion 302 of the drum member 30 (between the drum portion 300 and the hub portion 304 in the axial direction of the automatic transmission 20) and the outer periphery of the outer cylindrical portion 312 of the support member 31 are fixed by welding. As a result, the deviation between the fixed position of the drum member 30 and the support member 31 and the center of gravity of the drum member 30 in the axial direction of the automatic transmission 20 is reduced, thereby suppressing deformation of the drum member 60 during high rotation, etc. Furthermore, in the embodiment, no clutch other than the clutch C3 is disposed within the drum member 30 (particularly, on the side closer to the drum portion 300 than the cylindrical portion 302). Figure 3 Therefore, it is possible to prevent the length of the drum 300 side from becoming longer than the fixed position of the drum member 30 and the support member 31.

[0056] Furthermore, in the embodiment, in the drum member 30, the diameter of the hub 304 that functions as the hub 304 of the clutch C4 is smaller than that of the drum 300 and the cylindrical portion 302 that function as the clutch drum of the clutch C3. Therefore, compared with structures with the same diameter of the drum 300 and the hub 304, and members with the same diameter of the cylindrical portion 302 and the hub 304, the diameter of the clutch C4 can be reduced.

[0057] Furthermore, in the embodiment, the outer diameter of the cylindrical portion 302 of the drum member 30 is smaller than the outer diameter of the centrifugal oil pressure release chamber 38 of the clutch C3, thus reducing the outer diameter of the cylindrical portion 302.

[0058] In the embodiment, relative to the cylindrical portion 302 of the drum member 30, the engagement oil chamber 36 of the clutch C3 is formed by dividing the outer cylindrical portion 312 of the piston 35 and the support member 31 in the radially inward direction, thus shortening the shaft length of the clutch C3.

[0059] In this embodiment, the clutch drum 41 of the clutch C4 is connected to the planetary gear carrier 21c of the first planetary gear mechanism 21, which is connected to the input shaft 20i, via a connecting member 42 having an inner cylinder portion 420, an annular wall portion 421, and an outer cylinder portion 422. That is, the input shaft 20i, the planetary gear carrier 21c of the first planetary gear mechanism 21, the connecting member 42, and the clutch drum 41 rotate as a single unit. Therefore, the rotational speed of the input shaft 20i can be indirectly detected by detecting the rotational speed of the clutch drum 41 using the speed sensor 50. Thus, by arranging the speed sensor 50 on the gearbox 11 further outward than the clutch drum 41, the rotational speed of the input shaft 20i can be indirectly detected. Therefore, compared to a structure where the speed sensor 50 is arranged near the input shaft 20i, the speed sensor 50 can be arranged more easily.

[0060] In addition, in the embodiment, the speed sensor 50 is arranged in such a way that it overlaps axially with the welded portion of the cylindrical portion 302 of the drum member 30 and the outer cylindrical portion 312 of the support member 31 when viewed radially, so that the axial space in the gearbox 11 can be effectively utilized.

[0061] Furthermore, in this embodiment, the diameter of the cylindrical portion 410 of the clutch drum 41 of the clutch C4 is smaller than the diameter of the drum portion 300 of the clutch C3. This allows for easy securing of the space for the rotary position sensor 50, or enables the reduction of the inner diameter of the location for the speed sensor 50 in the transmission 11. Additionally, the diameter of the hub portion 304 of the clutch C4 is smaller than the diameter of the clutch hub 32 of the clutch C3, thus ensuring the radial length of the friction plate 44f and the release plate 44s.

[0062] The drum component 30 and the support component 31 of the automatic transmission 20 used in the power transmission device 10 configured in this way are manufactured as follows, for example. Figure 5 This is a process diagram illustrating an example of the manufacturing process of this integrated component. Initially, the drum member 30 is formed by stamping (process S100), and the support member 31 is formed (process S110). Next, the outer periphery of the outer cylindrical portion 312 of the support member 31 is welded to the inner periphery of the cylindrical portion 302 of the drum member 30 (process S120), thus completing the integrated component of the drum member 30 and the support member 31. In this way, by forming the drum member 30 by stamping and fixing the drum member 30 and the support member 31 to form an integrated component by welding, compared with forming the drum member and the support member integrally by cutting or spinning, it is possible to increase the radial freedom (ease of changing the diameter of the drum portion 300 and the hub portion 304) and reduce costs.

[0063] In this embodiment, in the drum member 30, the diameter of the hub 304, which functions as the hub portion 304 of the clutch C4, is smaller than that of the drum portion 300 and the cylindrical portion 302, which function as the clutch drum of the clutch C3. However, the diameter of the hub portion 304 may also be approximately the same as that of the drum portion 300 and the cylindrical portion 302, and the diameters of the cylindrical portion 302 and the hub 304 may also be approximately the same within a range smaller than that of the drum portion 300.

[0064] In the embodiment, the outer diameter of the cylindrical portion 302 of the drum member 30 is smaller than the outer diameter of the centrifugal oil pressure release chamber 38 of the clutch C3, but it can also be approximately the same as or slightly larger than the outer diameter of the centrifugal oil pressure release chamber 38.

[0065] In one embodiment, the engagement oil chamber 36 of the clutch C3 is formed radially inwardly by dividing the outer cylindrical portion 312 of the piston 35 and the support member 31 relative to the cylindrical portion 302 of the drum member 30, but is not limited thereto.

[0066] In one embodiment, the diameter of the cylindrical portion 410 of the clutch drum 41 of the clutch C4 is smaller than the diameter of the drum portion 300 of the clutch C3, but they can also be approximately the same. Additionally, in one embodiment, the diameter of the hub portion 304 of the clutch C4 is smaller than the diameter of the clutch hub 32 of the clutch C3, but they can also be approximately the same.

[0067] In this embodiment, the speed sensor 50 is positioned on the gearbox 11 further outward than the clutch drum 41. However, the speed sensor 50 can be positioned at any other location as long as it is a location that can directly or indirectly detect the rotational speed of the input shaft 20i.

[0068] In one embodiment, the speed sensor 50 overlaps axially with the welded portion of the cylindrical portion 302 of the drum member 30 and the outer cylindrical portion 312 of the support member 31 when viewed radially, but it may also not overlap axially with the welded portion when viewed radially.

[0069] As described above, the main purpose of this application is to provide a transmission device 20, comprising: a first clutch C3 having a first clutch hub 32, a first clutch drum 300, a plurality of first friction engagement plates 34f fitted into the first clutch hub 32, a plurality of second friction engagement plates 34s fitted into the first clutch drum 300 alternately with the first friction engagement plates 34f, and a first piston 35 for frictionally engaging the first friction engagement plates 34f and the second friction engagement plates 34s; and a second clutch C4 having a second clutch hub 304, a second clutch drum 41, a plurality of third friction engagement plates 44f fitted into the second clutch hub 304, and a first piston 35 for frictionally engaging the first friction engagement plates 34f and the second friction engagement plates 34s; and a first piston 35 for frictionally engaging the first friction engagement plates 34f and the second friction engagement plates 34s. The third friction engagement piece 44f is alternately fitted into a plurality of fourth friction engagement pieces 44s of the second clutch drum, and a second piston 45 causes the third friction engagement piece 44f and the fourth friction engagement piece 44s to frictionally engage. The transmission device 20 includes: a drum member 30, which is a stamped product, having a drum portion 300 on one side of the axial direction that functions as the first clutch drum and a hub portion 304 on the other side of the axial direction that functions as the second clutch hub; and a support member 31, which is engaged with the inner circumference between the drum portion 300 and the hub portion 304 of the drum member 30 in the axial direction via a joint and has an annular wall portion 311.

[0070] The transmission device of this application includes: a drum member, which is a stamped product, having a drum portion on one side in the axial direction that functions as a first clutch drum of a first clutch, and a hub portion on the other side in the axial direction that functions as a second clutch hub of a second clutch; and a support member, which is joined to the inner circumference between the drum portion and the hub portion of the drum member in the axial direction via a joint and has an annular wall portion. Therefore, the drum member is fixed between the drum portion and the hub portion in the axial direction by the support member, thereby reducing the axial deviation between the fixed position of the drum member and the support member and the center of gravity of the drum member compared to fixing the drum member at its axial end by the support member. This suppresses deformation of the drum member during high rotation. Furthermore, the drum member can be formed by stamping, thus increasing the radial freedom of formation and reducing costs compared to integrally forming the drum member and support member by cutting or spinning.

[0071] In the transmission device of this application, the diameter of the hub 304 can be smaller than the diameter of the drum 300. This allows for a reduction in the diameter of the second clutch having the hub.

[0072] In the transmission device of this application, the annular wall portion 311 and the first piston 35 divide to form the engagement oil chamber 36 of the first clutch C3. The first clutch C3 also has a release chamber dividing forming member 37, which, together with the piston 35, divides to form a centrifugal oil pressure release chamber 38 for releasing the centrifugal oil pressure generated in the engagement oil chamber 36. The drum member 30 has a cylindrical portion 302, which is located axially between the drum portion 300 and the hub portion 304. The outer periphery of the support member 31 is engaged with the inner periphery of the cylindrical portion 302 via the joint portion. The outer diameter of the cylindrical portion 302 can be smaller than the outer diameter of the centrifugal oil pressure release chamber 37. This allows for a reduction in the diameter of the cylindrical portion.

[0073] In the transmission device of this application, the drum member 30 has a cylindrical portion 302 located axially between the drum portion 300 and the hub portion 304. The support member 31 has an outer cylindrical portion 312 extending axially from the outer periphery of the annular wall portion 311 and engaging with the inner periphery of the cylindrical portion 302 via the engagement portion. The annular wall portion 311 and the first piston 35 can be radially divided inward relative to the outer cylindrical portion 312 to form the engagement oil chamber 36. This allows for a reduction in the shaft length of the first clutch.

[0074] In the transmission device of this application, the drum member 30 has a cylindrical portion 302, which is located axially between the drum portion 300 and the hub portion 304. The outer periphery of the support member 31 is engaged with the inner periphery of the cylindrical portion 302 via the joint portion. The diameter of the hub portion 304 can be smaller than the diameter of the cylindrical portion 302. This allows for a further reduction in the diameter of the hub portion.

[0075] The transmission device of this application includes: a planetary gear mechanism 21 having a first rotating element 21s, a second rotating element 21r, and a third rotating element 21c. The first rotating element 21s is connected to a stationary member 11 and cannot rotate relative to the stationary member 11. The third rotating element 21c is always connected to the input member 20i. A first clutch C3 can connect and disconnect the second rotating element 21r and the fourth rotating element 25sb. A second clutch C4 can connect and disconnect the third rotating element 21c and the fourth rotating element 25sb. The components are arranged sequentially in the axial direction. The planetary gear mechanism 21, the first clutch C3, the second clutch C4, and the second clutch drum 41 are connected to the third rotating element 21c via a connecting member 42. The connecting member 42 has: a radial extension 421, the outer periphery of which is connected to the second clutch drum 41 and extends radially; and an axial extension 420, which extends axially toward the planetary gear mechanism 21 from the inner periphery of the radial extension 421 at a position more radially inward than the first clutch C3, and is connected to the third rotating element 21c at its free end. The inner periphery of the support member 31 can be supported by the outer periphery of the axial extension 420 to allow free rotation.

[0076] In this case, a speed sensor 50 for detecting the rotational speed of the clutch drum 41 can be configured on the housing 11 in a manner opposite to the outer peripheral surface of the second clutch drum 41.

[0077] In the transmission device of this application with a speed sensor, the second clutch drum 41 has a cylindrical portion 410, a plurality of fourth friction engagement plates 44s are fitted into the cylindrical portion 410, the cylindrical portion 410 has an oil hole 410h that is radially through, and the speed sensor 50 is also opposite to the outer peripheral surface of the cylindrical portion 410 at a position that does not overlap with the oil hole 410h in the axial direction when viewed from the radial direction.

[0078] In the transmission device of this application with a speed sensor, the drum member 30 has a cylindrical portion 302 located axially between the drum portion 300 and the hub portion 304. The outer periphery of the support member 31 is joined to the inner periphery of the cylindrical portion 302 via the joint. The speed sensor 50, when viewed radially, does not overlap with the joint between the cylindrical portion 302 and the support member 31 in the axial direction. This allows for efficient utilization of the axial space within the housing.

[0079] In the transmission device of this application that incorporates a speed sensor, the diameter of the second clutch drum 41 can be smaller than the diameter of the first clutch drum 300. This makes it easier to ensure space for the rotary position sensor or to reduce the inner diameter of the housing where the speed sensor is positioned. In this case, the diameter of the second clutch hub 304 can be smaller than the diameter of the first clutch hub 32. This ensures the radial length of the third and fourth friction plates.

[0080] The main purpose of this application for a method of manufacturing a transmission device is to provide a method for manufacturing a transmission device comprising: a drum member 30 having a drum portion 300 on one side in the axial direction that functions as a first clutch drum of a first clutch C3 and a hub portion 304 on the other side in the axial direction that functions as a second clutch hub of a second clutch C4; and a support member 31, which is joined via a joint to the inner circumference between the drum portion 300 and the hub portion 304 of the drum member 30 in the axial direction and has an annular wall portion 311, wherein the first clutch C3 has a first clutch hub 32, the drum portion 300, a plurality of first friction engagement plates 34f fitted into the first clutch hub 32, and a plurality of second friction engagement plates 34f alternately arranged with the first friction engagement plates 34f fitted into the drum portion 300. 4s, a first piston 35 that causes the first friction engagement piece 34f and the second friction engagement piece 34s to frictionally engage, the second clutch C4 having the hub 304, the second clutch drum 41, a plurality of third friction engagement pieces 44f fitted into the hub 304, a plurality of fourth friction engagement pieces 44s fitted into the second clutch drum alternately with the third friction engagement pieces 44f, and a second piston 45 that causes the third friction engagement pieces 44f and the fourth friction engagement pieces 44s to frictionally engage, wherein the manufacturing method of the transmission device includes: step (a), forming the drum member 30 and forming the support member 31 by stamping; and step (b), joining the inner periphery between the drum portion 300 and the hub portion 304 of the axially oriented drum member 30 and the outer periphery of the support member 31.

[0081] In the manufacturing method of the transmission device of this application, a drum member and a support member are formed by stamping, and the inner circumference between the drum portion and the hub portion of the drum member and the outer circumference of the support member are joined in the axial direction. Therefore, compared with integrally forming the drum member and support member by machining or spinning, it is possible to increase the degree of freedom in the radial direction and reduce costs. Furthermore, in this integral component of the drum member and support member, the drum member is fixed between the drum portion and the hub portion in the axial direction by the support member. Therefore, compared with fixing the axial end of the drum member by the support member, the axial deviation between the fixed position of the drum member and the support member and the center of gravity of the drum member can be reduced. This helps to suppress deformation of the drum member during high rotation.

[0082] The above describes the methods for implementing this application, but this application is not limited to this implementation method. Various methods can obviously be implemented without departing from the spirit of this application.

[0083] [Potential for Industrial Applications]

[0084] This invention can be used in industries such as the manufacturing of speed change devices.

Claims

1. A speed-changing device, comprising: A first clutch includes a first clutch hub, a first clutch drum, a plurality of first friction engagement plates fitted into the first clutch hub, a plurality of second friction engagement plates alternately fitted into the first clutch drum, and a first piston that frictionally engages the first friction engagement plates and the second friction engagement plates; and The second clutch includes a second clutch hub, a second clutch drum, a plurality of third friction engagement plates fitted into the second clutch hub, a plurality of fourth friction engagement plates fitted into the second clutch drum alternately with the third friction engagement plates, and a second piston that frictionally engages the third friction engagement plates and the fourth friction engagement plates. in, This speed change device has the following features: As a stamped product, the drum component has a drum portion on one side in the axial direction that functions as the first clutch drum and a hub portion on the other side in the axial direction that functions as the second clutch hub. as well as A support member, connected via a joint to the inner circumference between the drum portion and the hub portion of the drum member in the axial direction, and having an annular wall portion. The transmission device includes a planetary gear mechanism, which has a first rotating element, a second rotating element, and a third rotating element. The first rotating element is connected to a stationary component but cannot rotate relative to it. The third rotating element is always connected to the input component. The first clutch can connect and disconnect the second and fourth rotating elements. The second clutch can connect and disconnect the third and fourth rotating elements. The planetary gear mechanism, the first clutch, and the second clutch are sequentially arranged along the axial direction. The second clutch drum is connected to the third rotating element via a connecting member. The connecting member has: a radially extending portion, the outer periphery of which is connected to the second clutch drum and extends radially; And an axial extension, extending axially toward the planetary gear mechanism from the inner circumference of the radial extension at a position further radially inward than the first clutch, and connecting to the third rotating element at its free end. The inner circumference of the support member is supported by the outer circumference of the axial extension, allowing it to rotate freely.

2. The speed change device according to claim 1, wherein, The drum component also has a cylindrical portion located axially between the drum portion and the hub portion. The support member has an outer cylindrical portion that extends axially from the outer periphery of the annular wall portion and is joined to the inner periphery of the cylindrical portion via the joint portion. The annular wall portion and the first piston are radially inwardly divided to form a contact oil chamber relative to the outer cylinder portion. The diameter of the hub is smaller than the diameter of the cylindrical part.

3. The speed change device according to claim 1 or 2, wherein, A speed sensor for detecting the rotational speed of the clutch drum is disposed on the housing, facing the outer peripheral surface of the second clutch drum. The second clutch drum has a cylindrical portion, and a plurality of the fourth friction engagement plates are fitted into the cylindrical portion of the second clutch drum. The cylindrical portion of the second clutch drum has an oil hole that extends radially through it. The speed sensor is positioned opposite the outer circumferential surface of the cylindrical portion of the second clutch drum when viewed radially and not overlapping with the oil hole in the axial direction.

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