GEARBOX DEVICE

Abstract

The present disclosure provides a transmission device that can improve lubrication of a differential mechanism without using a pump. The present disclosure is a transmission device that includes a differential cage and a differential mechanism disposed within the differential cage. The differential mechanism includes first and second pinion gears and first and second side gears. The differential cage includes a housing, first and second sleeves connected to the housing, an oil discharge groove extending from an outer end of the first sleeve to the interior of the housing, and an oil introduction groove extending from an outer end of the second sleeve to the interior of the housing. The oil discharge groove is disposed such that the oil discharge groove reaches an interior of the housing on a radially outer side of the first side gear and its width increases toward the outer end of the first sleeve.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a transmission device. TECHNICAL BACKGROUND

[0002] In a transmission device having a differential mechanism, a configuration is known in which lubricating oil is supplied to the differential mechanism by means of a pump (see Patent Document 1). CONVENTIONAL DOCUMENTSPATENT DOCUMENTS

[0003] Patent Document 1: Japanese Unexamined Patent Application, Publication No. 2011-174582 SUMMARY OF THE INVENTION PROBLEMS TO BE SOLVED BY THE INVENTION

[0004] The transmission device described above requires a pump for oil supply, which makes a structure of the device complex.

[0005] In one aspect of the present disclosure, it is preferable to provide a transmission device that can improve lubrication of a differential mechanism without using a pump. MEANS TO SOLVE THE PROBLEMS

[0006] One aspect of the present disclosure is a transmission device comprising: a sun gear; a ring gear arranged concentrically with the sun gear; planetary gears meshing with the sun gear and the ring gear; a differential cage rotatably supporting the planetary gears; a differential mechanism arranged within the differential cage; a first output shaft and a second output shaft connected to the differential mechanism; and a transmission case rotatably supporting the differential cage.

[0007] The differential mechanism includes a first pinion gear and a second pinion gear, each of which has a rotational axis center perpendicular to a rotational axis center of the sun gear and facing each other; and a first side gear and a second side gear, each of which has a rotational axis center coincident with the rotational axis center of the sun gear and facing each other. The first side gear meshes with the first pinion gear and the second pinion gear and is connected to the first output shaft. The second side gear meshes with the first pinion gear and the second pinion gear and is connected to the second output shaft.

[0008] The differential cage includes a housing in which the first pinion gear, the second pinion gear, the first side gear, and the second side gear are housed; a first sleeve connected to the housing and through which the first output shaft is inserted; a second sleeve connected to the housing and through which the second output shaft is inserted; at least one oil discharge groove provided on an inner peripheral surface of the first sleeve and extending from an outer end of the first sleeve to an interior of the housing; and at least one oil introduction groove provided on an inner peripheral surface of the second sleeve and extending from an outer end of the second sleeve to the interior of the housing.

[0009] The at least one oil discharge groove reaches an interior of the housing at a radially outer side of the first side gear and its width increases towards the outer end of the first sleeve when viewed in the axial direction of the first side gear.

[0010] According to the above configuration, the oil drainage grooves are able to efficiently drain the oil from the inside of the housing. This improves the oil supply to the housing. As a result, the lubrication of the differential mechanism can be improved without the use of a pump.

[0011] In one aspect of the present disclosure, the width of the at least one first oil introduction groove may increase toward the housing. According to the above configuration, oil can be efficiently supplied to the differential mechanism by the centrifugal force resulting from the rotation of the differential cage.

[0012] In one aspect of the present disclosure, the transmission device may include a connecting member including a communication hole that allows an opening at the outer end of the first sleeve to communicate with an exterior of the sun gear. The sun gear may overlap with the first sleeve in a radial direction of the sun gear. According to the above configuration, the oil discharged from the housing can be returned a short distance to a speed reduction system including the sun gear. As a result, oil circulation can be improved.

[0013] In one aspect of the present disclosure, the transmission element may include the connecting element, the connecting hole, and a diameter-enlarged portion whose inner diameter is larger than the outer end of the first sleeve. According to the above configuration, the oil can be stored in the diameter-enlarged portion. This promotes oil drainage through the connecting holes. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic sectional view of a transmission device in one embodiment. Fig. 2 is a partially enlarged schematic sectional view of the transmission device of Fig. 1. Fig. 3 is a schematic perspective view of planetary gears and a differential cage in the transmission device of Fig. 1. Fig. 4 is a schematic perspective view of a portion of the differential cage of Fig. 3. Fig. 5 is a schematic rear view of a portion of the differential cage of Fig. 3. Fig. 6 is a schematic perspective view of a portion of a gear housing in the transmission device of Fig. 1. Fig. 7 is a schematic cross-sectional view taken along line VII-VII of Fig. 1. Fig. 8 is a partially enlarged view of Fig. 2. Fig. 9A is a schematic diagram showing a state in which the differential cage rotates relatively in a first direction. Fig. 9B is a schematic diagram showing a state in which the differential cage rotates relatively in a second direction. Fig. 10 is a schematic front view of a portion of the differential cage of Fig. 3. EXPLANATION OF THE REFERENCE FIGURES

[0014] 1...transmission device, 2...sun gear, 3...ring gear, 4...planetary gears, 5...planetary gear bearing, 6...differential cage, 7...differential mechanism, 8A...first output shaft, 8B...second output shaft, 9...gearbox housing, 10...motor shaft, 22...diameter-enlarged part, 23...connecting holes, 61...case, 62...carrier, 63...bearing holder, 64...first sleeve, 65A to 65D...oil discharge grooves, 66...second sleeve, 67A to 67D...oil introduction grooves, 71 and 72...pinion gears, 73...pinion shaft, 74 and 75...side gears, 631...cylindrical parts, 632...legs, 633...pockets, 661 and 662...projections, 911...projection, 912...slope, 913...recess. MODE FOR CARRYING OUT THE INVENTION

[0015] Embodiments to which the present disclosure is applied will now be described with reference to the drawings. [1. First execution][1-1. Configuration]

[0016] One in Fig. The transmission device 1 shown in Fig. 1 is a device mounted in an automobile and transmitting a driving force from a driving source of the automobile to a wheel thereof.

[0017] The transmission device 1 comprises a sun gear 2, a ring gear 3, planetary gears 4, planetary gear bearings 5, a differential cage 6, a differential mechanism 7, a first output shaft 8A, a second output shaft 8B, a transmission housing 9 and a motor shaft 10.

[0018] In the present embodiment, an axial direction of the sun gear 2 is an X-axis, a vertical direction of the sun gear 2 is a Z-axis, and a direction perpendicular to both the X-axis and Z-axis is a Y-axis. <motorwelle>

[0019] The motor shaft 10 is drivingly connected to a motor (not shown) and is axially rotated by the driving force of the motor. <sonnenrad>

[0020] The sun gear 2, together with the ring gear 3 and the planetary gears 4, forms a planetary gear mechanism (i.e., a gear reduction mechanism). The sun gear 2 is arranged outside the differential cage 6 and inside the transmission housing 9.

[0021] The sun gear 2 is drivingly connected to the motor shaft 10 and is axially rotated by the drive force of the motor. A rotational axis center of the sun gear 2 is equal to a rotational axis center of the first output shaft 8A and the second output shaft 8B.

[0022] The first output shaft 8A and the first sleeve 64 of the differential cage 6 are inserted through the sun gear 2. As shown in Fig. 2, the sun gear 2 includes a toothed part 21, a diameter-enlarged part 22, connecting holes 23 and a connecting part 24. Fig. 2 illustrates a state in which the planetary gear 4 is moved from an upper position to Fig. 1 is moved downwards by circulation.

[0023] The gear part 21 is an external gear, which is cylindrical and meshes with the planetary gears 4. The first sleeve 64 of the differential cage 6 is inserted into the gear part 21 such that a small radial gap exists. In other words, the sun gear 2 overlaps with the first sleeve 64 in the radial direction of the sun gear 2. An inner diameter of the gear part 21 is larger than an outer diameter of the first sleeve 64.

[0024] The diameter-enlarged part 22 is a tubular portion connected to the gear part 21. The diameter-enlarged part 22 is connected to an end of the gear part 21 opposite the differential mechanism 7. An inner diameter D1 of the diameter-enlarged part 22 is larger than an inner diameter D2 of an outer end 64A of the first sleeve 64. The first sleeve 64 is not inserted into the diameter-enlarged part 22. The inner diameter D1 of the diameter-enlarged part 22 is larger than an outer diameter of a portion of the motor shaft 10 that is inserted into the connecting part 24.

[0025] The communication holes 23 each allow an opening in the outer end 64A of the first sleeve 64 to communicate with a space outside the sun gear 2. The communication holes 23 are spaced apart from each other in the circumferential direction of the diameter-enlarged portion 22. In the present embodiment, four communication holes 23 are spaced 90° apart from each other in the circumferential direction of the sun gear 2. However, the number of communication holes 23 is not limited to four.

[0026] The connecting holes 23 allow lubricating oil discharged from the first sleeve 64 to be discharged by gravity or centrifugal force into a planetary gear receiving space located between the differential cage 6 and the transmission case 9. The sun gear 2, in the present embodiment, serves as a gear constituting a planetary gear mechanism and as a connecting member defining a circulation path for the lubricating oil.

[0027] The connecting part 24 is a tubular section that adjoins the enlarged diameter part 22. The connecting part 24 is connected to an end of the enlarged diameter part 22 opposite the toothed part 21. As shown in Fig. As shown in Figure 1, an end portion of the motor shaft 10 is splined onto the connecting part 24. An inner diameter of the connecting part 24 is smaller than that of the enlarged diameter part 22. <ringrad>

[0028] The ring gear 3 is arranged concentrically with the sun gear 2. The ring gear 3 is attached to an inner surface of the gear housing 9 and does not rotate relative to the gear housing 9. The ring gear 3 is an internal gear with which the planetary gears 4 mesh. <planetenrad>

[0029] The planetary gears 4 mesh with the sun gear 2 and the ring gear 3, respectively. The planetary gears 4 revolve around the axial rotation center of the sun gear 2. In the present embodiment, three planetary gears 4 are arranged, but the number of planetary gears 4 is not limited to three.

[0030] The rotational center of each of the planetary gears 4 is parallel to the rotational center of the sun gear 2 (i.e., the X-axis). The planetary gears 4 are held by the differential cage 6. Each of the planetary gears 4 includes a first gear part 41, a second gear part 42, a first shaft 43, and a second shaft 44.

[0031] The first gear part 41 is an external gear that meshes with the sun gear 2. The second gear part 42 is an external gear that meshes with the ring gear 3. The outer diameter of the second gear part 42 is smaller than that of the first gear part 41. The second gear part 42 is arranged closer to an opening end 9A of the transmission case 9 than the first gear part 41.

[0032] The first shaft 43 constitutes an end portion of each planetary gear 4 opposite the opening end 9A. The first shaft 43 is supported by a carrier 62 of the differential cage 6. Specifically, the first shaft 43 is inserted through a ball bearing 5A supported by the carrier 62.

[0033] The second shaft 44 represents an end portion of each planetary gear 4 closer to the opening end 9A. The second shaft 44 is supported by the differential cage 6. Specifically, the second shaft 44 is inserted through a corresponding planetary gear bearing 5 supported by a bearing retainer 63 of the differential cage 6. <planetenradlager>

[0034] Through each of the planetary gear bearings 5, a corresponding one of the second shafts 44 of the planetary gears 4 is inserted. The planetary gear bearings 5 ​​are not subject to any particular restrictions as long as the bearings can rotatably support the planetary gears 4, but, for example, known needle bearings are preferred. <Differentialkäfig>

[0035] The differential cage 6 rotatably supports the planetary gears 4 and accommodates the differential mechanism 7. The differential cage 6 is rotatably mounted on the transmission housing 9. While the planetary gears 4 rotate, the differential cage 6 rotates around the center of the rotational axis of the sun gear 2.

[0036] As in Fig. 2, the differential cage 6 includes a housing 61, the carrier 62, the bearing holders 63, the first sleeve 64, the oil discharge grooves 65A, 65B, 65C, 65D, a second sleeve 66, and oil introduction grooves 67A, 67B, 67C, 67D.

[0037] Fig. 2 shows only the first oil discharge groove 65A and the third oil discharge groove 65C, and the second oil discharge groove 65B and the fourth oil discharge groove 65D are in Fig. 4. Similarly, Fig. 2 only the first oil introduction groove 67A and the third oil introduction groove 67C, and the second oil introduction groove 67B and the fourth oil introduction groove 67D are in Fig. 5 shown. <Gehäuse>

[0038] The housing 61 is a main body of the differential cage 6 and accommodates the differential mechanism 7. As shown in Fig. 1, the housing 61 is formed by connecting a first part 61A and a second part 61B in a direction parallel to the X-axis. <Träger>

[0039] The bracket 62 is arranged such that the bracket 62 covers the housing 61 from a position of the gear case 9 opposite to the opening end 9A (i.e., a position closer to the motor shaft 10). The bracket 62 is fixed to the housing 61 by a fastening member, for example, a bolt. <lagerhalter>

[0040] The bearing holders 63 each hold a corresponding one of the planetary gear bearings 5. As in Fig. 3, the bearing holders 63 are arranged on an outer peripheral surface of the housing 61.

[0041] The bearing holders 63 are spaced apart from each other in the circumferential direction of the housing 61 (i.e., the circumferential direction of the sun gear 2). The bearing holders 63 each include a cylindrical part 631, a leg 632, and a pocket 633.

[0042] Each of the cylindrical parts 631 holds one of the planetary gear bearings 5. Specifically, the planetary gear bearings 5 ​​are axially inserted into the cylindrical parts 631. The leg 632 extends from the outer peripheral surface of the housing 61 and connects the housing 61 radially outward to the cylindrical part 631.

[0043] The pocket 633 of each bearing holder 63 protrudes from an end of the cylindrical portion 631 opposite the corresponding planetary gear 4. The pocket 633 is recessed from a radially inner side of the sun gear 2 to a radially outer side of the sun gear 2 (i.e., in the direction away from the rotational axis center of the sun gear 2) to provide an internal space. Also, each pocket 633 overlaps with the corresponding planetary gear bearing 5 in the axial direction of the sun gear 2.

[0044] In other words, each pocket 633 includes a bottom wall intersecting the radial direction of the sun gear 2, two side walls intersecting the circumferential direction of the sun gear 2, and a front wall intersecting the X-axis. The front wall in each pocket 633 covers a portion of the corresponding planetary gear bearing 5 and a portion of the corresponding cylindrical part 631 in the direction parallel to the X-axis. The internal space in each pocket 633 allows fluid to enter from the radially inner side of the sun gear 2. The internal space in each pocket 633 communicates with a cavity in the cylindrical part 631.

[0045] The bearing retainers 63 are integral with the housing 61 and serve as a portion of the first part 61A. The cylindrical part 631 and the pocket 633 in each pocket 633 are integral with each other. Each pocket 633 is formed simultaneously with a hole in the corresponding cylindrical part 631 when the first part 61A is machined. This makes it relatively easy to form the pockets 633, which are difficult to form by casting due to their small thickness. <erste Hülse>

[0046] The Fig. The first sleeve 64 shown in Fig. 1 is a tubular portion connected to the housing 61 and through which the first output shaft 8A is inserted.

[0047] The first sleeve 64 extends from the housing 61 to the motor shaft 10 along the X-axis. The first sleeve 64 allows an interior of the housing 61 and an exterior of the housing 61 (specifically, an interior in the sun gear 2) to communicate with each other.

[0048] A portion of the first sleeve 64 is inserted into the sun gear 2. A center axis of the first sleeve 64 coincides with the rotational axis center of the sun gear 2. An inner diameter of the first sleeve 64 is smaller than a maximum inner diameter of the housing 61. <Oil drainage groove>

[0049] As in Fig. 4, the first oil discharge groove 65A, the second oil discharge groove 65B, the third oil discharge groove 65C, and the fourth oil discharge groove 65D are provided on an inner peripheral surface of the first sleeve 64 and extend from the outer end 64A of the first sleeve 64 into the housing 61.

[0050] The first oil discharge groove 65A, the second oil discharge groove 65B, the third oil discharge groove 65C, and the fourth oil discharge groove 65D are spaced apart from each other in the circumferential direction of the first sleeve 64. Details of the shapes of the oil discharge grooves 65A to 65D are described below. <zweite Hülse>

[0051] The Fig. The second sleeve 66 shown in Fig. 1 is a tubular portion connected to the housing 61 and through which the second output shaft 8B is inserted.

[0052] The second sleeve 66 extends from the housing 61 to the opening end 9A of the gear case 9 along the X-axis. The second sleeve 66 allows the interior of the housing 61 and the exterior of the housing 61 (specifically, the interior of the gear case 9) to communicate with each other.

[0053] The second sleeve 66 is inserted into a differential cage bearing 93. A center axis of the second sleeve 66 coincides with the rotational axis center of the sun gear 2. An inner diameter of the second sleeve 66 is smaller than the maximum inner diameter of the housing 61.

[0054] As in Fig. 3, the second sleeve 66 includes a first protrusion 661 and a second protrusion 662. The first protrusion 661 and the second protrusion 662 each protrude relative to other positions on an outer end 66A of the second sleeve 66 in an axial direction of the second side gear 75 (i.e., along the X-axis).

[0055] One end of the first projection 661 in the circumferential direction of the second sleeve 66 is located at a position adjacent to the first oil introduction groove 67A, and the other end is located at a position adjacent to the third oil introduction groove 67C.

[0056] In other words, the first protrusion 661 is located in a region between one end of the first oil introduction groove 67A and one end of the third oil introduction groove 67C, at the outer end 66A of the second sleeve 66. The first protrusion 661 provides a guide for guiding oil into the first oil introduction groove 67A and the third oil introduction groove 67C.

[0057] The second projection 662 has the shape of the first projection 661 rotated by 180° around the rotational axis center of the differential cage 6. One end of the second projection 662 in the circumferential direction of the second sleeve 66 is located at a position adjacent to the second oil introduction groove 67B (see Fig. 5), and the other end is in a position adjacent to the fourth oil introduction groove 67D (see Fig. 5).

[0058] In other words, the second protrusion 662 is located in a region between one end of the second oil introduction groove 67B and one end of the fourth oil introduction groove 67D, at the outer end 66A of the second sleeve 66. The second protrusion 662 provides a guide for guiding oil into the second oil introduction groove 67B and the fourth oil introduction groove 67D. <Oil introduction groove>

[0059] As in Fig. 5, the first oil introduction groove 67A, the second oil introduction groove 67B, the third oil introduction groove 67C, and the fourth oil introduction groove 67D are located on an inner peripheral surface of the second sleeve 66 and extend from the outer end 66A of the second sleeve 66 into the housing 61.

[0060] The first oil introduction groove 67A, the second oil introduction groove 67B, the third oil introduction groove 67C, and the fourth oil introduction groove 67D are spaced apart from each other in the circumferential direction of the second sleeve 66. Details of the shapes of the oil introduction grooves 67A to 67D will be described below. <differentialmechanismus>

[0061] The Fig. The differential mechanism 7 shown in Fig. 1 is a known mechanism that distributes and transmits the rotation of the differential cage 6 to the first output shaft 8A and the second output shaft 8B while the first output shaft 8A and the second output shaft 8B rotate at different speeds.

[0062] The differential mechanism 7 includes a first pinion 71, a second pinion 72 (see Fig. 5), a pinion shaft 73, a first side gear 74, and the second side gear 75. The differential mechanism 7 is arranged within the differential cage 6. Specifically, the first pinion 71, the second pinion 72, the pinion shaft 73, the first side gear 74, and the second side gear 75 are housed in the housing 61 of the differential cage 6. <Ritzel und Ritzelwelle>

[0063] As in Fig. 5, the first pinion 71 and the second pinion 72 are each a bevel gear whose rotational axis center is perpendicular to the rotational axis center of the sun gear 2 (i.e., the X-axis).

[0064] The axial center of rotation of the first pinion 71 and the center of rotation of the second pinion 72 coincide. The first pinion 71 and the second pinion 72 are arranged opposite each other. The first pinion 71 and the second pinion 72 have the same shape and are mirror images of each other.

[0065] The pinion shaft 73 supports the first pinion 71 and the second pinion 72 for individual rotation. A central axis (i.e., longitudinal direction) of the pinion shaft 73 is perpendicular to the X-axis. The pinion shaft 73 is fixed to the housing 61 and does not rotate with respect to the differential cage 6. In other words, the pinion shaft 73 rotates together with the housing 61 around the rotational axis center of the sun gear 2. <seitenrad>

[0066] As in Fig. 1, the first side gear 74 and the second side gear 75 are each bevel gears whose rotational axis center coincides with the rotational axis center of the sun gear 2 (i.e., the X-axis).

[0067] The center of rotation of the first side gear 74 and the center of rotation of the second side gear 75 coincide. The first side gear 74 and the second side gear 75 are arranged opposite each other.

[0068] The first side gear 74 is arranged closer to the motor shaft 10 along the X-axis than the second side gear 75. The first side gear 74 and the second side gear 75 have the same shape and are mirror images of each other.

[0069] The first side gear 74 and the second side gear 75 are each rotatably supported on the housing 61. The first side gear 74 meshes with the first pinion 71 and the second pinion 72 and is connected to the first output shaft 8A. The second side gear 75 meshes with the first pinion 71 and the second pinion 72 and is connected to the second output shaft 8B.

[0070] The first side gear 74 and the second side gear 75 rotate together with the differential cage 6 and at the same time also rotate relative to the differential cage 6 by rotation transmitted from the first pinion 71 and the second pinion 72. <ausgangswelle>

[0071] The first output shaft 8A and the second output shaft 8B are each longitudinally toothed with the first side gear 74 and the second side gear 75.

[0072] The first output shaft 8A and the second output shaft 8B rotate a wheel of an automobile. The first output shaft 8A and the second output shaft 8B rotate according to a rotational direction of the engine shaft 10 (i.e., the rotational direction of the differential cage 6) while rotating at different speeds through the differential mechanism 7 connected thereto. <Getriebegehäuse>

[0073] The gear housing 9 accommodates the sun gear 2, the ring gear 3 and the planet gears 4 and rotatably supports the differential cage 6.

[0074] The transmission case 9 includes a first body 91, a second body 92, the differential cage bearing 93, and an oil guide 94. The first body 91 and the second body 92 are connected to each other to thereby form the planetary gear accommodation space that accommodates the gears and the differential cage 6. A motor (not shown) serving as a drive source is arranged within the second body 92.

[0075] The first body 91 has the opening end 9A through which the second output shaft 8B is inserted. Lubricating oil for lubricating the gears and shafts is stored in the planetary gear receiving space in the gear case 9. The planetary gear receiving space is sealed with a sealing member or the like.

[0076] The differential cage bearing 93 rotatably supports the differential cage 6. Specifically, the second sleeve 66 of the differential cage 6 is inserted through the differential cage bearing 93. The differential cage bearing 93 is held by the first body 91. The differential cage bearing 93 is a shielded bearing through which the lubricating oil supplied from the oil guide 94 can flow.

[0077] The Fig. 6 and Fig. The oil guide 94 shown in Figure 7 is a flow channel having a groove-like shape and arranged in the planetary gear accommodation space. An inlet 941 of the oil guide 94 is arranged above the rotational axis center of the sun gear 2 and on a radially outer side relative to an orbit of the planetary gears 4. The inlet 941 is arranged in a position overlapping with the first gear parts 41 of the planetary gears 4 in the radial direction of the sun gear 2.

[0078] When the car moves forward, the Fig. 7, the sun gear 2 and the differential cage 6 rotate clockwise, and each planetary gear 4 rotates clockwise while rotating counterclockwise around its own axis. The direction of rotation of each component is the same when the car is moving backward and opposite to the direction the car is moving forward.

[0079] The lubricating oil stored in a lower portion of the planetary gear receiving space is scooped up by the rotating planetary gear 4 and then drops into the inlet 941. This allows the lubricating oil to be fed into the oil guide 94.

[0080] An outlet 942 of the oil guide 94 is arranged below the inlet 941 and near the upper end of the outer end 66A of the second sleeve 66 of the differential cage 6 (see Fig. 1). The lubricating oil supplied from the inlet 941 of the oil guide 94 flows down inside the oil guide 94 and is delivered to the vicinity of the second sleeve 66.

[0081] As in Fig. 2, the lubricating oil supplied near the second sleeve 66 passes through the second sleeve 66 and is supplied to the interior of the housing 61. This allows lubrication of the differential mechanism 7. The lubricating oil within the differential mechanism 7 passes through the first sleeve 64 and is discharged into the interior of the sun gear 2 (i.e., a connecting member).

[0082] The lubricating oil discharged into the interior of the sun gear 2 is discharged from the connecting holes 23 into the planetary gear accommodation space and is then stored again in the lower portion of the planetary gear accommodation space. The lubricating oil stored in the planetary gear accommodation space is supplied to the oil guide 94 through the planetary gears 4, as described above. The lubricating oil thus circulates in the transmission case 9.

[0083] A part of the lubricating oil supplied to the vicinity of the second sleeve 66 is not supplied to the housing 61, but passes through a shield of the differential cage bearing 93 and then flows downward under the second sleeve 66 and the housing 61 and is stored in the lower portion of the planetary gear receiving space. <Zufuhr von Schmieröl zum Planetenradlager>

[0084] As in Fig. As shown in Fig. 8, a portion of the lubricating oil is supplied to each planetary gear bearing 5 along an inner peripheral surface of the first body 91 of the transmission case 9. The flow of the lubricating oil is described in detail below.

[0085] The first body 91 of the gear housing 9 includes a projection 911, a slant surface 912, and a recess 913. The projection 911 is arranged to overlap with the pocket 633 of each bearing holder 63 from the radially inner side of the sun gear 2, and projects toward the planetary gear bearings 5 ​​in the axial direction of the sun gear 2.

[0086] In other words, the protrusion 911 is a portion that protrudes from an inner surface of the first body 91 and covers a portion of an opening of each pocket 633. The protrusion 911 is located closer to the radially inner side of the sun gear 2 than a rotation axis L of each planetary gear 4 (i.e., a center axis of each planetary gear bearing 5).

[0087] In the present embodiment, the protrusion 911 is annular when viewed along the axial direction of the sun gear 2. In other words, the protrusion 911 is provided in the entire circumferential direction of the first body 91. However, the protrusion 911 may be provided only at the lower portion of the first body 91 (for example, a portion below the rotational axis center of the sun gear 2).

[0088] The inclined surface 912 is inclined toward the projection 911 from a position that is farther away from the planetary gear bearings 5 ​​than the projection 911 in the axial direction of the sun gear 2 and that is located on an inner side relative to the projection 911 in the radial direction of the sun gear 2.

[0089] In other words, the inclined surface 912 is formed from a portion of the inner surface of the first body 91 extending from the projection 911 toward the opening end 9A. The inclined surface 912 may be formed from a flat surface, or may be curved or bent.

[0090] The recess 913 is a portion located in a back surface of the projection 911 on the radially outer side of the sun gear 2 (i.e., a surface opposite the inclined surface 912), and also recessed toward the radially inner side of the sun gear 2. The recess 913 is a groove extending along the circumferential direction of the sun gear 2. The recess 913 may be provided in the entire circumferential direction of the first body 91, or may be provided only at the lower portion of the first body 91 (for example, at a portion where the lubricating oil entering the recess 913 flows downward).

[0091] As in Fig. 8 with an arrow, the lubricating oil that passes through the shield of the differential cage bearing 93 via the oil guide 94 and flows down under the second sleeve 66, or the lubricating oil that does not pass through the oil guide 94 but directly reaches the inclined surface 912 because it is splashed in the transmission case 9, moves along the inclined surface 912 toward the projection 911. The lubricating oil that has reached the projection 911 falls from its outer end and is collected in the pocket 633.

[0092] The lubricating oil that has moved from the outer end of the projection 911 to the rear side of the projection 911 is removed from the rear side of the projection 911 through the recess 913. Accordingly, the lubricating oil is prevented from flowing along the inner surface of the first body 91 below the pocket 633. <Formen der Ölzufuhrnut und der Ölabführnut>

[0093] As in Fig. 5, the oil introduction grooves 67A to 67D each reach the interior of the housing 61 on a radially outer side of the second side gear 75 relative to the second side gear 75, as viewed along an axial direction of the second side gear 75 (i.e., a direction parallel to the X-axis). The exit ends of the oil introduction grooves 67A to 67D each have portions that do not overlap with the rotating second side gear 75.

[0094] Further, the oil introduction grooves 67A to 67D are each arranged such that, when viewed along the axial direction of the second side gear 75, the oil introduction grooves 67A to 67D do not overlap with either the first pinion 71 or the second pinion 72.

[0095] The first oil introduction groove 67A and the second oil introduction groove 67B are arranged side by side between the first pinion 71 and the second pinion 72 in the circumferential direction of the second side gear 75. The shape of the second oil introduction groove 67B is symmetrical to that of the first oil introduction groove 67A with respect to a virtual plane perpendicular to the Y-axis.

[0096] The shape of each of the third oil introduction groove 67C and the fourth oil introduction groove 67D is symmetrical with the shape of the first oil introduction groove 67A or the second oil introduction groove 67B with respect to a virtual plane perpendicular to the Z axis. That is, the third oil introduction groove 67C and the fourth oil introduction groove 67D are arranged opposite to the first oil introduction groove 67A and the second oil introduction groove 67B via the pinion shaft 73, and are arranged side by side between the first pinion 71 and the second pinion 72 in the circumferential direction of the second side gear 75.

[0097] The oil introduction grooves 67A to 67D each extend linearly. In other words, a line connecting the centers of each of the oil introduction grooves 67A to 67D in the width direction thereof is a straight line. Further, the width of each of the oil introduction grooves 67A to 67D increases toward the housing 61. In other words, the width of each of the oil introduction grooves 67A to 67D is minimum at the outer end 66A of the second sleeve 66 and maximum inside the housing 61.

[0098] As in the Fig. 9A and Fig. 9B, the first oil introduction groove 67A and the second oil introduction groove 67B are arranged between the first projection 661 and the second projection 662 of the second sleeve 66 in the circumferential direction of the second side gear 75 (that is, in the circumferential direction of the second sleeve 66), and also the third oil introduction groove 67C and the fourth oil introduction groove are arranged in the other area between the first oil introduction groove 67A and the second oil introduction groove 67B.

[0099] Specifically, ends of each of the first oil introduction groove 67A and the second oil introduction groove 67B are located in a region between a first end portion 661A of the first projection 661 and a first end portion 662A of the second projection 662. Ends of each of the third oil introduction groove 67C and the fourth oil introduction groove 67D are located in a region between a second end portion 661B of the first projection 661 and a second end portion 662B of the second projection 662.

[0100] As in Fig. As shown in Fig. 9A, when the differential cage 6 rotates relative to the second output shaft 8B, the lubricating oil O in the planetary gear accommodating space impacts the first end portion 661A of the first projection 661 and is introduced into the first oil introduction groove 67A. Alternatively, the lubricating oil O impacts the second end portion 662B of the second projection 662 and is introduced into the fourth oil introduction groove 67D.

[0101] As in Fig. 9B, when the differential cage 6 rotates in a second direction R2 opposite to the first direction R1 relative to the second output shaft 8B, the lubricating oil O in the planetary gear accommodating space impacts the second end portion 661B of the first projection 661 and is guided into the third oil introduction groove 67C. Alternatively, the lubricating oil O impacts the first end portion 662A of the second projection 662 and is guided into the second oil introduction groove 67B.

[0102] As in Fig. As shown in FIG. 10, the oil discharge grooves 65A to 65D each reach the interior of the housing 61 on a radially outer side of the first side gear 74 relative to the first side gear 74, as viewed in an axial direction of the first side gear 74 (i.e., the direction parallel to the X-axis). The exit ends of the oil discharge grooves 65A to 65D each have portions that do not overlap with the first rotating side gear 74.

[0103] Fig. 10 is a diagram of the interior of the housing 61, when viewed from the second sleeve 66. The first pinion 71, the second pinion 72, the pinion shaft 73 and the second side gear 75 are shown in Fig. 10 omitted.

[0104] The oil discharge grooves 65A to 65D are each arranged at a position overlapping with the first pinion 71 or the second pinion 72 when viewed along the axial direction of the first side gear 74. Further, the oil discharge grooves 65A to 65D are each arranged between any two of the oil introduction grooves 67A to 67D in the circumferential direction of the first side gear 74 when viewed along the axial direction of the first side gear 74.

[0105] As in Fig. 4, the oil discharge grooves 65A to 65D each extend linearly. Furthermore, the width of the oil discharge grooves 65A to 65D each increases toward the outer end 64A of the first sleeve 64. In other words, the width of each of the oil introduction grooves 67A to 67D is minimum at the housing 61 and maximum at the inner side of the outer end 64A of the first sleeve 64. [1-2. Effects]

[0106] According to the details described above, the following effects can be achieved.

[0107] (1a) The oil discharge grooves 65A-65D allow the oil to be efficiently discharged from the inside of the housing 61. This improves the oil supply to the housing 61. As a result, the lubrication of the differential mechanism 7 can be improved without using a pump.

[0108] (1b) The oil introduction grooves 67A-67D each have an increased width to allow the oil to be efficiently supplied to the differential mechanism 7 by the centrifugal force resulting from the rotation of the differential case 6.

[0109] (1c) The connecting member (ie, the sun gear 2) including the connecting hole 23 allows the oil discharged from the housing 61 to be returned over a short distance to a speed reduction system including the sun gear 2. As a result, the oil circulation can be improved.

[0110] The enlarged diameter portion 22 of the sun gear 2, which is the connecting element, contains the connecting holes 23 to allow the oil to be stored in the enlarged diameter portion 22. This promotes oil drainage through the connecting holes 23. [2. Other versions]

[0111] Although the embodiment of the present disclosure has been described above, it should be understood that the present disclosure is not limited to the above-described embodiment but can be implemented in various forms.

[0112] (2a) In the transmission device of the above-described embodiment, the oil introduction groove need not necessarily be linear. For example, the oil introduction groove may also be spiral.

[0113] (2b) In the transmission device of the above-described embodiment, the number of oil introduction grooves and the number of oil discharge grooves are not limited to four. For example, the number of oil introduction grooves and the number of oil discharge grooves are not limited to a number equal to or less than three (including one).

[0114] (2c) In the transmission device of the above-described embodiment, the sun gear does not necessarily have to function as a connecting member. For example, the motor shaft may serve as the connecting member including the connecting hole. Alternatively, the connecting member may be a member separate from the sun gear and the motor shaft. Furthermore, the connecting member does not necessarily have to include the diameter-enlarged part.

[0115] (2d) Two or more functions of one component in the embodiments described above may be distributed among two or more components, or the functions of two or more components may be integrated into a single component. Also, a portion of the configurations of the embodiments may be omitted. At least a portion of the configurations of the embodiments may be added or replaced by them. Note that any form included in the technical idea defined by the wording of the appended claims may be an embodiment of the present disclosure. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] JP 2011-174582

[0003] < / ausgangswelle> < / seitenrad> < / differentialmechanismus> < / lagerhalter> < / planetenradlager> < / planetenrad> < / ringrad> < / sonnenrad> < / motorwelle>

Claims

[1] Transmission device comprising: a sun gear; a ring gear arranged concentrically to the sun gear; Planetary gears that mesh with the sun gear and the ring gear; a differential cage that rotatably supports the planetary gears; a differential mechanism disposed within the differential cage; a first output shaft and a second output shaft connected to the differential mechanism; and a gear housing rotatably supporting the differential cage, the differential mechanism including: a first pinion and a second pinion, the respective rotational axis centers of which are perpendicular to the rotational axis center of the sun gear and which face each other; and a first side gear and a second side gear, the respective rotational axis center of which coincides with the rotational axis center of the sun gear and which face each other, wherein the first side gear meshes with the first pinion and with the second pinion and is connected to the first output shaft, the second side gear meshes with the first pinion and with the second pinion and is connected to the second output shaft, where the differential cage contains: a housing in which the first pinion, the second pinion, the first side gear and the second side gear are accommodated; a first sleeve connected to the housing and through which the first output shaft is inserted; a second sleeve connected to the housing and through which the second output shaft is inserted; at least one oil discharge groove provided on an inner peripheral surface of the first sleeve and extending from an outer end of the first sleeve to an interior of the housing; and at least one oil introduction groove provided on an inner peripheral surface of the second sleeve and extending from an outer end of the second sleeve to the interior of the housing, and the at least one oil discharge groove reaches an interior of the housing on a radially outer side of the first side gear and its width, when viewed in the axial direction of the first side gear, increases towards the outer end of the first sleeve. [2] The transmission device according to claim 1, wherein the width of the at least one first oil introduction groove increases toward the housing [3] The transmission device according to claim 1 or 2, further comprising: a connecting member including a communication hole allowing an opening at the outer end of the first sleeve to communicate with an exterior of the sun gear, wherein the sun gear overlaps with the first sleeve in a radial direction of the sun gear. [4] The transmission device according to claim 3, wherein the connecting member includes the connecting hole and a diameter-enlarged part whose inner diameter is larger than the outer end of the first sleeve.

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