Differential cover

Abstract

The invention relates to a differential cover for accommodating at least one compensating gear of a differential gear set of a differential transmission. The differential cover is provided with a circumferential side face on the outer side in the radial direction, the circumferential side face is used for arranging a gear, to be pushed from a pushing side and to be fixed to the differential cover, of the differential transmission device, and the differential cover is further provided with a flange protruding outwards in the radial direction. The flange is axially located on one side of the peripheral side face away from the pushing side. In order to enable the differential cover to be universally used for welding to different types of gears, a first joint surface and a second joint surface are provided on the flange, which first joint surface and the second joint surface are used as substitutes for each other to form a welding joint for a welding connection to the gear to be fixed. The first joint surface is designed to point radially outward on the flange and the second joint surface is designed to point axially towards the thrust side on the flange.

Description

Technical Field

[0001] The present invention relates to a differential cover for accommodating at least one compensation gear of a differential gear set of a differential transmission device, wherein the differential cover has a peripheral side surface on the outer side in the radial direction, and the peripheral side surface is used to place a gear of the differential transmission device to be pushed from the push-on side and to be fixed on the differential cover, and wherein the differential cover is also provided with a flange protruding radially outward, and the flange is axially located on a side of the peripheral side surface away from the push-on side. In addition, the present invention also relates to a differential transmission device having the above-mentioned differential cover. Background Art

[0002] The differential transmission is used to distribute the drive torque introduced on the drive side to the two output sides and to achieve a speed difference between the output sides. The differential transmission usually has a differential cover in which at least one compensating gear is rotatably supported, wherein the at least one compensating gear then meshes with the output gear teeth of the output side. The drive torque is distributed to the two output sides by means of this tooth meshing, wherein the at least one compensating gear can compensate for the speed difference between the output sides by performing a rotational movement in the differential cover. The coupling of the drive side is usually achieved at the differential cover by means of a gear, which is usually designed as a ring gear and is usually welded to the differential cover.

[0003] A differential transmission is known from patent document EP 1 248 922 B1, in which a differential cover is welded to a gear in the form of a disk gear. The differential cover is provided with a peripheral side surface on the outside in the radial direction, which forms a hub for placing the disk gear. In addition, a surrounding flange is provided at the differential cover, which protrudes radially outward and has a surrounding contact surface pointing radially outward. When assembling the differential transmission, the disk gear is pushed onto the differential cover from the push-on side, wherein the disk gear is guided on the one hand at the peripheral side surface and on the other hand at the contact surface of the flange. The axial position of the disk gear relative to the differential cover can be freely selected within a feasible guidance range, wherein the differential cover and the disk gear are welded to each other after the desired axial position is set. Summary of the invention

[0004] Based on the above-described prior art, the object of the present invention is to provide a differential cover for a differential transmission, wherein the differential cover should be universally suitable for welding connection with different types of gears in order to reduce the manufacturing effort.

[0005] This object is achieved based on the preamble of claim 1 in combination with its characterizing features. The dependent claims following claim 1 accordingly reflect advantageous developments of the invention. Furthermore, a differential transmission in which a differential cover according to the invention is provided is the subject of claim 10.

[0006] According to the present invention, a differential cover for accommodating at least one compensation gear of a differential gear set of a differential transmission device is provided. In addition, the differential cover has a peripheral side surface on the outside in the radial direction, and the peripheral side surface is used to place the gear of the differential transmission device to be pushed from the push-on side and to be fixed on the differential cover. In addition, the differential cover is also provided with a flange protruding radially outward, and the flange is axially located on the side of the peripheral side surface away from the push-on side.

[0007] The differential cover according to the invention is therefore intended for use in a differential transmission, wherein for this differential transmission, the differential cover serves to accommodate, and in particular rotatably support, at least one compensating gear of a differential gear set of the differential transmission. The differential cover preferably defines an interior space in which, in the mounted state of the differential cover, the differential gear set is accommodated and in which the rotatable support of the at least one compensating gear in the differential cover also takes place. In particular, the differential cover can have a pot-like or cover-like shape for this purpose.

[0008] The differential cover is provided with a peripheral side surface radially on the outside, on which the gear to be fixed on the differential cover is placed after the fixing is completed. The peripheral side surface is designed in particular to be circumferentially on the differential cover and is preferably formed by a cylindrical part of the differential cover. In addition, the differential cover has a flange protruding radially outwards axially adjacent to the peripheral side surface. Very particularly preferably, the flange protrudes radially outwards further on the differential cover than the peripheral side surface. In addition, the flange is designed in particular to be circumferentially on the differential cover.

[0009] The gear to be fixed on the differential cover is pushed onto the differential cover from the push-on side, wherein the flange is axially arranged on a side away from the push-on side relative to the circumferential side. The gear to be fixed is in particular a ring gear.

[0010] In the sense of the present invention, “axial” refers to a direction parallel to the axis of rotation of the differential cover, and “radial” refers to a direction along a diameter centered on the axis of rotation.

[0011] The present invention includes the following technical teachings, namely, a first joint surface and a second joint surface are provided at the flange, and the first joint surface and the second joint surface are used to form welded joints connected to the gear to be fixed as replacements for each other. The first joint surface is configured to point radially outward at the flange, and the second joint surface is designed to point axially toward the push-on side at the flange. In other words, the flange of the differential cover is therefore provided with two joint surfaces, which are used to form mutually replacing fixing positions of the gears at the differential cover, so that welding joints connected to the gear to be fixed can be formed at the two joint surfaces accordingly, and thus welding connections can be produced accordingly. Here, the first joint surface at the flange points radially outward, so that the joint welding connected to the gear to be fixed is carried out in a radial direction at the first joint surface. The second joint surface points axially toward the push-on side at the flange, so that the joint welding connected to the gear to be fixed is carried out in an axial direction at the second joint surface.

[0012] This design of the differential cover has the advantage that the differential cover can be used without problems as a universal part for welding to different variants of the gears to be fixed, due to the two connection surfaces formed on the flange. Due to the first connection surface pointing radially outwards and the second connection surface pointing axially toward the push-on side, gears with different sizes and / or fixing areas can be welded to the differential cover in a correspondingly secure manner without problems. This can reduce the manufacturing effort, because the differential cover according to the invention can be used as a universal part to produce differential transmissions of different designs, i.e. with different gears to be fixed to the differential cover.

[0013] The first connection surface is configured to point radially outward at the flange, wherein the first connection surface particularly preferably forms the radial outer boundary of the flange, ie is configured to be located radially outward of the flange. If the flange is configured to be circumferential, the first connection surface is also configured to be circumferential.

[0014] The second joint surface is oriented axially toward the push-on side at the flange. If the flange is designed to be circumferential, the second joint surface is also preferably designed to be circumferential. Since the flange is designed to protrude radially outward at the differential cover, the second joint surface is especially basically designed as an annular surface.

[0015] It is important for the present invention that the two joint surfaces are respectively designed to form a welded joint connected to the gear to be fixed, so that a welded connection of the differential cover to the gear to be fixed can be produced at the corresponding welded joint. Thus, when each welded joint is formed between the flange and the gear to be fixed, a joint is formed in each case, in which a weld seam can be formed to connect the two components by welding. Here, the first joint surface and the second joint surface form surfaces that replace each other for forming a welded joint, that is, a welded joint is formed at the first joint surface or at the second joint surface in order to weld the differential cover to the gear to be fixed in this regard. When the first joint surface is used, a joint is formed radially between the differential cover and the gear, and when the second joint surface is used, the joint extends axially between the differential cover and the gear.

[0016] According to an embodiment of the present invention, a joining side wall (Fugenflanke) is provided at the first joint surface, and the joining side wall is bent axially in the direction opposite to the push-on side. In this case, the first joint surface at the flange is not designed on a constant outer diameter, but the flange has a variable outer diameter in the area of ​​the first joint surface, thereby defining the joining side wall. This has the advantage that a specific shape can be achieved at the first joint surface to achieve a specific weld during welding. Depending on whether the joining side wall is to extend over the entire axial range of the first joint surface or only over an axial partial area of ​​the first joint surface, the flange is provided with a variable outer diameter in the entire area of ​​the first joint surface or has a variable outer diameter in a portion and a constant outer diameter in a portion.

[0017] Depending on which weld shape is to be achieved at the first joint surface during welding, the joining side wall of the first joint surface can be designed as a chamfered portion, thereby, for example, presenting a semi-V-groove or a Y-groove on the side of the differential cover, or the joining side wall of the first joint surface can be designed as a rounded portion, thereby, for example, achieving a semi-U-groove.

[0018] As an alternative or supplement to this, a feasible design of the present invention is that a radially outwardly curved joint sidewall is provided at the second joint surface. As a result, a specific shape can also be achieved at the second joint surface by the designed joint sidewall and thus a specific weld seam can be achieved during welding. Here, the joint sidewall can extend over the entire radial extension of the second joint surface or only over a radial partial area of ​​the second joint surface. The former is preferably achieved by narrowing the flange over the entire area of ​​the second joint surface, while in the second case, the flange is narrowed in particular only over the corresponding radial partial area of ​​the second joint surface.

[0019] The joining side wall of the second joint surface can be designed as a chamfered portion so as to form, for example, a semi-V-shaped groove or a Y-shaped groove shape on the side of the differential cover during welding. Alternatively, the joining side wall of the second joint surface can also be designed as a rounded portion so as to obtain a weld seam in the form of a semi-U-shaped groove at the differential cover after welding.

[0020] In a further development of the present invention, the first connection surface and the second connection surface are separated from each other by an edge at the flange. In this case, the first connection surface and the second connection surface are directly adjacent to each other at the flange. If the first connection surface and the second connection surface are designed to be circumferential, the edge is also configured to be circumferential.

[0021] Another embodiment of the invention is that the second joint surface is delimited radially inwardly by an undercut. This is particularly combined with the previous variant so that the second joint surface is delimited radially inwardly by an undercut and radially outwardly by an edge. If the second joint surface is designed to be circumferential, the undercut is also designed to be circumferential.

[0022] According to a feasible design solution of the present invention, the flange is provided with a contact surface radially inside relative to the second joint surface, the contact surface being oriented axially toward the push-on side and being used to contact the gear to be fixed. The flange is therefore also used in an advantageous manner to define the axial final position of the gear to be fixed on the differential cover.

[0023] In a further development of the invention, the differential cover has a transversely extending receiving opening for receiving a bearing pin for the at least one compensation gear. The receiving opening extends transversely to the rotation axis of the differential cover and can be designed as a through hole.

[0024] The invention also relates to a differential transmission, comprising a differential cover according to one or more of the above-described variants. The differential cover is welded to a gear, which is in particular a ring gear. The welded connection is made at a weld seam, which is provided at one of the two joint faces of the differential cover. The differential transmission is in particular a bevel gear differential transmission, but alternatively it can also be a cylindrical gear differential transmission, a planetary gear differential transmission, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Advantageous embodiments of the invention are shown in the accompanying drawings and are explained below.

[0026] Figure 1 shows a cross-sectional view of a portion of a known differential transmission;

[0027] Figure 2 A cross-sectional view showing a region of a differential cover according to a preferred embodiment of the present invention;

[0028] Figure 3 Shows Figure 2 Details of the differential cover shown;

[0029] Figure 4 Shows Figure 2 A cross-sectional view of a differential cover shown with a first gear fixed to the differential cover; and

[0030] Figure 5 Shows Figure 2 A cross-sectional view of a differential cover is shown, wherein a second gear is fixed to the differential cover. DETAILED DESCRIPTION

[0031] Figure 1 The sectional view shows a part of a differential transmission 1 belonging to the prior art, wherein the differential transmission 1 is designed as a bevel gear differential. The differential transmission 1 comprises a differential cover 2 which accommodates a differential gear set 4 of the differential transmission 1 in an interior space 3 .

[0032] The differential gear set 4 comprises two output bevel gears 5 and 6 and a plurality of compensating gears 7, which are designed as bevel gears and are rotatably supported on bearing pins 8. Here, each compensating gear 7 is in toothed engagement with the output bevel gears 5 and 6. The bearing pins 8 are received in transversely extending receiving holes 9 in the differential cover 2, so that the compensating gears 7 are guided in a rotatably supported manner in the differential cover 2. In a manner known in principle to a person skilled in the art, the introduced driving torque is transmitted to the bearing pins 8 via the differential cover 2 and is thus converted into a rotation of the compensating gears 7, which drive the two output bevel gears 5 and 6 here due to the toothed engagement and distribute the introduced driving torque evenly to the output bevel gears 5 and 6 here. By means of the rotational movement on the bearing pins 8, the compensating gears 7 can also achieve a speed difference between the output bevel gears 5 and 6 here.

[0033] In order to introduce the driving torque, the differential cover 2 is fixed Figure 1 The gear, which is not shown in detail, can be designed as a crown gear. It is known to those skilled in the art that the gear can be fixed to the differential cover 2 by a welded connection in addition to a screw connection.

[0034] Figure 2 A cross-sectional view of a differential cover 10 is shown, which is designed according to a preferred embodiment of the present invention and can be used to replace Figure 1 The differential cover 2 in the differential transmission 1 of the present invention. Therefore, the differential cover 10 also defines an inner space 11 for accommodating the differential gear set, and is laterally penetrated by an accommodating hole 12, which is used to accommodate a bearing pin for at least one compensation gear.

[0035] Radially on the outside, the differential cover 10 is provided with a circumferential lateral surface 13 and a circumferential flange 14, wherein the lateral surface 13 is used to accommodate a gear which can be fastened to the differential cover 10 and for this purpose can be pushed onto the differential cover 10 from a push-on side 15. The flange 14 is axially formed on the side of the lateral surface 13 facing away from the push-on side 15 and projects radially outward relative to the rest of the differential cover 10.

[0036] Figure 3 The flange 14 is shown in more detail, wherein it can be seen here that the flange 14 defines a circumferential contact surface 16 adjacent to the lateral surface 13. The contact surface 16 forms a stop for the gear wheel to be pushed onto the differential cover 10 and to be fixed, in that the gear wheel contacts the contact surface 16 when being pushed on and thus defines the axial end position of the gear wheel on the differential cover 10.

[0037] Furthermore, two connection surfaces 17 and 18 are provided at the flange 14, wherein the connection surface 17 is arranged to point radially outward at the flange 14, while the connection surface 18 is bent axially in the direction of the push-on side 15. As a special feature, the two connection surfaces 17 and 18 are provided here as mutually alternative fixing areas, so that gears of different variants can be fixed to the differential cover 10 accordingly. Specifically, the connection surfaces 17 and 18 are respectively designed for forming welded joints for welding connections with the respective gears to be fixed.

[0038] exist Figure 4 , the differential cover is shown for the fastening of a gear 19, which is a disk gear. The gear 19 is pushed onto the differential cover 10 using a through hole 20, wherein the gear 19 is placed on a guide surface 21 on the circumferential side 13 of the differential cover 10 and also contacts the contact surface 16 of the flange 14 with the end face 22. The connection surface 18 of the flange 14 and the connection surface 23 of the gear 19 axially opposite thereto form an axial weld joint 24, which defines a weld joint 25. The weld joint 25 is designed here so that a weld seam can be introduced to weld the gear 19 to the differential cover 10, which is designed here as a combined YU-type weld seam. The axial welding is performed here, in particular, by laser welding.

[0039] In order to realize such a shape of the weld seam, a joining side wall 26 is provided at the joint surface 18, which is designed as a chamfered portion and is bent radially outward. Here, the joining side wall 26 extends over the entire joint surface 18, so as to realize a shape representing a semi-Y-joint at the joint surface 18. The chamfer angle of the joining side wall 26 is preferably in the range of 5° to 15°.

[0040] Figure 5The differential cover 10 is shown with a gear 27 fixed thereto, which is also designed as a ring gear, but is designed in this case in a similar manner to the differential cover 10. Figure 4 The gear 27 is different from the gear 19 in the differential cover 10 in order to achieve a different gear change compared to the gear 19 when connected to the drive side of the differential cover 10. The gear 27 is also pushed onto the differential cover 10 using the through hole 28 and is placed on the guide surface 29 on the circumferential side 13 of the differential cover 10. The axial end position of the gear 27 on the differential cover 10 is predetermined by the contact of the gear 27 at the end face 30 with the contact surface 16 of the flange 14. In the axial end position, the connection surface 17 of the flange 14 and the connection surface 31, which is designed on the side of the gear 27 and radially opposite to the connection surface 17 in the axial end position, form a radial weld joint 32. By means of this weld joint 32, a weld joint 33 located radially between the flange 14 and the gear 27 is defined, which is used to introduce a weld in the form of a combined YU-shaped weld. This radial welding is also carried out here, in particular, by laser welding.

[0041] like Figure 3 In particular, as shown, the shape of the weld joint 33 is limited on one side of the flange 14 by also designing a joint side wall 34 at the joint surface 17. The joint side wall 34 is also designed as a chamfered portion, which is bent axially in the direction opposite to the push-on side 15. The joint side wall 34 extends over the entire joint surface 17, thereby achieving a shape representing a semi-Y-shaped weld on the joint surface 17. The chamfer angle of the joint side wall 34 is preferably in the range of 5° to 15°.

[0042] In the case of the flange 14, the connection surfaces 17 and 18 are designed adjacent to one another, wherein the connection surfaces 17 and 18 are separated from one another by a circumferential edge 35. Furthermore, the connection surface 18 is delimited radially inwardly by an undercut 36 and is separated from the contact surface 16.

[0043] With the design according to the present invention, a differential cover which is generally suitable for welding connection with different types of gears can be provided.

[0044] List of reference numerals:

[0045] 1 Differential drive

[0046] 2 Differential cover

[0047] 3. Internal Space

[0048] 4 Differential gear sets

[0049] 5 Output bevel gear

[0050] 6 Output bevel gear

[0051] 7 Compensation gear

[0052] 8 Bearing pin

[0053] 9 Receiving hole

[0054] 10 Differential cover

[0055] 11. Internal Space

[0056] 12 Receiving hole

[0057] 13 weeks side view

[0058] 14 Flange

[0059] 15 Push-on side

[0060] 16 Contact surface

[0061] 17 Joint surface

[0062] 18 Joint surface

[0063] 19 Gear

[0064] 20 Through Holes

[0065] 21 Guide surface

[0066] 22 End face

[0067] 23 Joint surface

[0068] 24 Welding joints

[0069] 25 Welding joints

[0070] 26 Joining side walls

[0071] 27 Gear

[0072] 28 Through Holes

[0073] 29 Guide surface

[0074] 30 End face

[0075] 31 Joint surface

[0076] 32 Welding joints

[0077] 33 Welding joints

[0078] 34 Joining side walls

[0079] 35 Edges

[0080] 36 Undercut.

Claims

1. A differential cover (10) for accommodating at least one compensating gear (7) of a differential gear set (4) of a differential transmission (1), wherein: The differential cover (10) has a peripheral side surface (13) on the radially outer side, and the peripheral side surface is used to accommodate the gears (19, 27) of the differential transmission device (1) to be pushed from the push-on side (15) and to be fixed on the differential cover (10), and wherein the differential cover (10) is also provided with a flange (14) protruding radially outward, and the flange is axially located on the side of the peripheral side surface (13) away from the push-on side (15), characterized in that a first joint surface (17) and a second joint surface (18) are provided at the flange (14), and the first joint surface and the second joint surface are used to form welded joints (24, 32) welded to the gears (19, 27) to be fixed as replacements for each other, so that the first joint surface (17) is configured to point radially outward at the flange (14), and the second joint surface (18) is designed to point axially toward the push-on side (15) at the flange (14).

2. The differential cover (10) according to claim 1, characterized in that: A joining side wall (34) is provided at the first joint surface (17), and the joining side wall is bent in the axial direction in the direction opposite to the push-on side (15).

3. The differential cover (10) according to claim 2, characterized in that: The joining side wall (34) of the first joint surface (17) is designed as a chamfered portion or a rounded portion.

4. The differential cover (10) according to any one of claims 1 to 3, characterized in that: A joining side wall (26) is provided on the second joint surface (18), and the joining side wall is bent outward in the radial direction.

5. The differential cover (10) according to claim 2, characterized in that: The joining side wall (26) of the second joint surface (18) is designed as a chamfered portion or a rounded portion.

6. A differential cover (10) according to any one of the preceding claims, characterised in that The first connection surface (17) and the second connection surface (18) are separated from each other by an edge (35) at the flange (14).

7. A differential cover (10) according to any one of the preceding claims, characterised in that The second joint surface (18) is delimited radially inwardly by a recess (36).

8. A differential cover (10) according to any one of the preceding claims, characterised in that The flange (14) is provided with a contact surface (16) radially inwardly relative to the second connection surface (18), the contact surface being oriented axially toward the push-on side (15) and being used for contacting a gear (19, 27) to be fixed.

9. A differential cover (10) according to any one of the preceding claims, characterised in that The differential cover (10) has a transversely extending receiving hole (12) for receiving a bearing pin (8) for the at least one compensating gear (7).

10. A differential transmission, in particular a bevel gear differential transmission, comprising a differential cover according to any one or more of claims 1 to 9, wherein: The differential cover is welded to a gear, in particular a crown gear, at a weld seam which is formed at one of the two connection surfaces of the differential cover.

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