A main reduction gear and differential case integrated welded differential

Abstract

The present invention discloses a main reduction gear and differential housing integrated welded differential, which relates to the technical field of automobile parts assembly, and aims to solve the problem that when the product needs to meet high torque, the differential volume is often relatively large. In the design of the welding connection between the main reduction gear and the differential housing, the welding diameter also has a direct impact on the torque capacity of the product, and the problem of small volume and large torque capacity cannot be achieved at present. The key points of its technical solution are that it includes a differential housing and a rotating gear set, the differential housing includes a housing and a main reduction gear integrated with the housing, one end of the differential housing is radially welded with a differential housing end cover, and a clearance hole for the rotating gear set to be placed is opened on the end face of the differential housing. During forging, the differential housing and the main reduction gear are produced in an integrated manner, eliminating the current later bolt connection or laser welding of the main reduction gear and the differential housing, and then the differential housing and the differential housing end cover are radially welded, which effectively increases the rigidity of the differential, so that it can have a stronger torque capacity in a smaller volume.

Description

Technical Field

[0001] The invention relates to the technical field of automobile parts assembly, in particular to a main reduction gear and differential housing integrated welded differential. Background Art

[0002] The differential is an important and indispensable component of the automobile transmission system, and is also one of the key factors affecting the life and noise of the entire transmission. In the current market, the differential and the main reduction gear are designed separately, and there are two ways to connect the main reduction gear and the differential housing (hereinafter referred to as the differential housing): laser welding and main body bolting.

[0003] The differential case has a one-piece window structure and a two-piece split structure. Figure 1 and Figure 2 , is a one-piece window differential housing, and two windows 11 are symmetrically arranged on the differential housing 1. Since the differential housing 1 is an integral structure, the planetary gears and the side gears of the differential need to be installed in the differential housing 1 through the windows 11. The planetary shaft that rotates with the planetary gear can only be fixed on the mounting through hole 12 between the two windows 11. The size of the window 11 is large, so that the strength of the differential housing 1 is not high.

[0004] The above-mentioned prior art solutions have the following defects: Under the above-mentioned connection method between the differential and the main reduction gear, the torque capacity of the differential is obviously proportional to its volume. When the product needs to meet high torque, the volume of the differential is often relatively large, which is a great challenge to the product envelope. In the design of the welding connection between the main reduction gear and the differential housing, the welding diameter also has a direct impact on the torque capacity of the product. In the current market, it is impossible to find a product with both small volume and large torque capacity, so further improvement is needed. Summary of the invention

[0005] The object of the present invention is to provide a main reduction gear and differential housing integrated welded differential, which has the effects of relatively small volume and large torque capacity, and radial welding to enhance welding strength.

[0006] The above technical objectives of the present invention are achieved through the following technical solutions:

[0007] A main reduction gear and differential housing integrated welded differential, comprising a differential housing and a rotating gear set arranged in the differential housing, the differential housing comprising a housing and a main reduction gear integrated with the housing, a differential housing end cover is radially welded to one end of the differential housing, and a clearance hole for placing the rotating gear set is opened on the end surface of the differential housing opposite to the differential housing end cover.

[0008] The present invention is further configured as follows: an annular welding groove 1 with a triangular cross-section is provided on the end surface of the differential housing end cover opposite to the differential housing, and an annular welding groove 2 corresponding to the annular welding groove 1 is provided on the end surface of the differential housing opposite to the differential housing end cover.

[0009] The present invention is further configured as follows: a connecting ring is coaxially arranged on the end face of the differential housing end cover opposite to the differential housing, the outer diameter of the connecting ring is smaller than the outer diameter of the end face of the differential housing end cover, and the outer diameter of the connecting ring is equal to the inner diameter of the clearance hole.

[0010] The present invention is further configured as follows: the rotating gear set includes a plurality of differential main gears and side gears meshing with the differential main gears, and the differential main gears are evenly distributed at equal intervals along the circumference of the differential case.

[0011] The present invention is further configured as follows: two differential main gears are provided, two side gears are provided, and a gear shaft is connected between the two differential main gears.

[0012] The present invention is further configured as follows: a through hole for the gear shaft to pass through is opened on the circumferential side surface of the connecting ring.

[0013] In summary, the beneficial technical effects of the present invention are:

[0014] 1. By setting the differential housing with the main reduction gear, the differential housing and the main reduction gear are produced in an integrated manner during forging, eliminating the need for later bolt connection or laser welding between the main reduction gear and the differential housing in the current market, and eliminating the consideration of whether the welding meets the strength requirements; the differential housing and the differential housing end cover are then radially welded. Compared with axial welding, radial welding has higher strength and stability, effectively increasing the rigidity of the differential, so that it can have a stronger torque capacity in a smaller volume;

[0015] 2. By setting the annular solder groove 1 and the annular solder groove 2, the contact area between the tin liquid and the differential shell and the differential shell end cover is increased, and the welding strength is further improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic diagram of the structure of a one-piece window differential shell in the background technology Figure 1 ;

[0017] Figure 2 This is a schematic diagram of the structure of a one-piece window differential shell in the background technology Figure 2 ;

[0018] Figure 3 is a schematic diagram of the assembly structure of a differential assembly in an embodiment of the present invention;

[0019] Figure 4 is an exploded schematic diagram of various components in an embodiment of the present invention;

[0020] Figure 5 It is a cross-sectional schematic diagram used to show the assembly structure;

[0021] Figure 6 yes Figure 5 Enlarged schematic diagram of part A.

[0022] In the figure, 1, differential housing; 11, window; 12, mounting through hole; 13, clearance hole; 2, differential housing end cover; 3, annular welding groove 1; 4, annular welding groove 2; 5, connecting ring; 51, through hole; 6, differential main gear; 61, side gear; 62, gear shaft. DETAILED DESCRIPTION

[0023] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0024] Reference Figure 3 and Figure 4 , which is a main reduction gear and differential housing integrated welded differential disclosed by the present invention, including a differential housing 1 and a rotating gear set arranged in the differential housing 1, the differential housing 1 including a housing and a main reduction gear integrated with the housing, a differential housing end cover 2 is radially welded to one end of the differential housing 1, and a clearance hole 13 for placing the rotating gear set is opened on the opposite end faces of the differential housing 1 and the differential housing end cover 2. The differential housing and the main reduction gear are produced in an integrated manner during forging, eliminating the need for later bolt connection or laser welding of the main reduction gear and the differential housing in the current market, and eliminating the consideration of whether the welding meets the strength requirements; the differential housing 1 and the differential housing end cover 2 are then radially welded, and compared with axial welding, the strength and stability of radial welding are higher, which effectively increases the rigidity of the differential, so that it can have a stronger torque capacity in a smaller volume.

[0025] Reference Figure 5 and Figure 6 In order to further improve the welding strength between the differential housing 1 and the differential housing end cover 2, an annular welding groove 1 3 with a triangular cross section is provided on the end surface of the differential housing end cover 2 opposite to the differential housing 1, and an annular welding groove 2 4 corresponding to the annular welding groove 1 3 is provided on the end surface of the differential housing 1 opposite to the differential housing end cover 2. The contact area between the tin liquid and the differential housing 1 and the differential housing end cover 2 is increased, and the welding strength is further improved.

[0026] Reference Figure 4 and Figure 5, a connecting ring 5 is coaxially arranged on the end face of the differential housing end cover 2 opposite to the differential housing 1, the outer diameter of the connecting ring 5 is smaller than the outer diameter of the end face of the differential housing end cover 2, and the outer diameter of the connecting ring 5 is equal to the inner diameter of the clearance hole 13. In this embodiment, the rotating gear set includes two differential main gears 6 and side gears 61 meshing with the differential main gears 6, and the two differential main gears 6 are evenly distributed at equal intervals along the circumference of the differential housing 1. Two side gears 61 are correspondingly arranged, and a gear shaft 62 is connected between the two differential main gears 6. A through hole 51 for the gear shaft 62 to pass through is opened on the circumferential side of the connecting ring 5. After the rotating gear assembly is installed in the differential housing end cover 2, the differential housing end cover 2 and the differential housing 1 are welded. The two-piece design can reduce the axial envelope of the product and facilitate product layout. This design successfully avoids the process in which gear grinding must be performed after welding in order to achieve high precision of gears and deformation of laser welding in traditional designs. If the production process of welding first and then grinding the gear is followed, the assembly of the internal parts of the differential will be a great challenge. The integrated main reduction gear designed in this design greatly simplifies the assembly of the internal parts of the differential while taking into account the gear accuracy.

[0027] The implementation principle of this embodiment is: the differential housing and the main reduction gear are produced in an integrated manner during forging, eliminating the later bolt connection or laser welding of the main reduction gear and the differential housing in the current market, and eliminating the consideration of whether the welding meets the strength requirements;

[0028] After the rotating gear is assembled into the differential case end cover 2, the assembly of the small assembly is completed, and then the assembled differential case end cover 2 small assembly is radially laser welded with the differential case 1 to complete the production of the differential assembly. The differential can be made relatively small in size while greatly improving the torque capacity. The welding of the differential case end cover 2 to the differential case 1 simplifies the design of the tooling, and can achieve radial welding and enhance the welding strength.

[0029] The traditional process of welding first and then grinding the gears will limit the assembly of the internal parts of the differential assembly and have the risk of interference. This two-piece housing reduces the difficulty of assembling the internal parts of the differential and can avoid the process of welding first and then grinding the gears, without considering the deformation of welding, thereby improving the accuracy of the gears.

[0030] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A main reduction gear and differential housing integrated welded differential, comprising a differential housing (1) and a rotating gear set arranged in the differential housing (1), characterized in that: The differential housing (1) comprises a housing and a main reduction gear integrated with the housing, the main reduction gear is a helical gear provided on the periphery of the differential housing, one end of the differential housing (1) is radially welded with a differential housing end cover (2), and a clearance hole (13) for placing a rotating gear set is provided on the end surface of the differential housing (1) opposite to the differential housing end cover (2); a connecting ring (5) is coaxially provided on the end surface of the differential housing end cover (2) opposite to the differential housing (1), the outer diameter of the connecting ring (5) is smaller than the outer diameter of the end surface of the differential housing end cover (2), and the outer diameter of the connecting ring (5) is The inner diameter of the clearance hole (13) is equal to that of the differential housing (1), thereby improving the coaxiality between the differential housing (1) and the differential housing end cover (2); an annular welding groove (3) with a triangular cross section is radially provided on the end surface of the differential housing end cover (2) opposite to the differential housing (1); an annular welding groove (4) corresponding to the annular welding groove (3) is radially provided on the end surface of the differential housing (1) opposite to the differential housing end cover (2), thereby reducing the axial envelope of the product and avoiding deformation during welding; a slot hole is provided below the triangular area formed by the annular welding groove (3) and the annular welding groove (4).

2. The main reduction gear and differential case integrated welded differential according to claim 1, characterized in that: The rotating gear set comprises a plurality of differential main gears (6) and side gears (61) meshing with the differential main gears (6), and the differential main gears (6) are evenly distributed at equal intervals along the circumference of the differential housing (1).

3. The main reduction gear and differential case integrated welded differential according to claim 2, characterized in that: Two differential main gears (6) are provided, two side gears (61) are provided, and a gear shaft (62) is connected between the two differential main gears (6).

4. The main reduction gear and differential case integrated welded differential according to claim 3, characterized in that: A through hole (51) for the gear shaft (62) to pass through is provided on the circumferential side surface of the connecting ring (5).

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