Pinion and differential assembly

Abstract

A side gear rotatable about an axis, the side gear including a plurality of gear teeth extending laterally therefrom; a housing member rotatable about an axis, the housing member covering the side gear; one or more holes formed in the housing member, the one or more holes extending in a direction parallel to the axis; and one or more pinions, each having an upper surface and a length, the pinions being inserted in a corresponding one of the one or more holes in a direction parallel to the axis, and the pinions having one or more pinion teeth extending transversely from the pinions, wherein each pinion is configured to mesh with the side gear via one or more pinion teeth, and wherein, starting from an upper surface of the pinion, a dimension of the one or more pinion teeth along a first length portion of the pinion is greater than a dimension of the one or more pinion teeth along a second length portion of the pinion.

Description

[0001] Cross-reference to related applications

[0002] This application claims the benefit of and priority to U.S. Provisional Application No. 63 / 338,691, filed on May 5, 2022, and entitled “Pinion Support Ring,” the contents of which are incorporated herein by reference in their entirety. Technical Field

[0003] The present disclosure relates generally to differential devices for vehicles and the like, and more particularly to the configuration of pinion helical teeth. Background Art

[0004] There is an evolving need for lighter lubricants (e.g., lubricants having lower viscosities) in differentials. Thus, replacing a higher viscosity lubricant (such as the lubricant used in a differential mechanism) with a lower viscosity lubricant generally results in a reduction in the pressure bearing capacity of surfaces within the differential mechanism. For example, a low viscosity or diluted lubricant (e.g., lubricant oil) generally reduces the pressure bearing capacity of surfaces on portions of the differential that frequently come into contact with one another (e.g., the inner surfaces of a pinion gear and its corresponding bore) due to the use of a lower viscosity lubricant. Summary of the invention

[0005] In one aspect, the present technology relates to a side gear (semi-pinion) rotatable about an axis, the side gear including a plurality of gear teeth extending laterally therefrom; a housing member rotatable about the axis, the housing member covering the side gear; one or more holes formed in the housing member, the one or more holes extending in a direction parallel to the axis; and one or more pinions, each pinion having an upper surface and a length, the pinion being inserted into a corresponding hole in the one or more holes in a direction parallel to the axis and having one or more pinion teeth extending laterally from the pinion, wherein each pinion is configured to mesh with the side gear via the one or more pinion teeth, and wherein a size of the one or more pinion teeth along a first length portion of the pinion starting from the upper surface of the pinion is greater than a size of the one or more pinion teeth along a second length portion of the pinion.

[0006] In an example of the above aspect, the lateral surface of the side gear has no gear teeth along the length of the first length portion of the side gear facing the pinion gear. In an example, the first length portion of the pinion gear is in the range of 10%-20% of the total length of the pinion gear in a direction parallel to the axis. In another example, the first length portion of the pinion gear is about 16% of the total length of the pinion gear in a direction parallel to the axis.

[0007] For another example, the width of one or more pinion teeth in the first length portion of the pinion gear is 25%-40% greater than the width of one or more pinion teeth in the second length portion. In another example of the above aspect, the width of one or more pinion teeth in the first length portion of the pinion gear is 32.5% greater than the width of one or more pinion teeth in the second length portion. In another example, one or more pinion teeth in the first portion and the second portion have a helical configuration, and the angle of the helical configuration in the first portion and the second portion is the same.

[0008] In another aspect, the technology relates to a pinion gear, comprising an upper surface; and one or more pinion gear teeth extending transversely from the pinion gear along the length of the pinion gear in its axial direction, the length comprising: a first portion extending from the upper surface in the axial direction of the pinion gear; and a second portion extending after the first portion in the axial direction of the pinion gear; wherein the size of the one or more pinion gear teeth in the first portion is greater than the size of the one or more pinion gear teeth in the second portion. For example, the length of the first portion of the pinion gear is in the range of 10%-20% of the total length of the pinion gear in the axial direction of the pinion gear. In an example, the length of the first portion of the pinion gear is about 16% of the total length of the pinion gear in the axial direction of the pinion gear. In another example, the width of the one or more pinion gear teeth in the first portion is 25%-40% greater than the width of the one or more pinion gear teeth in the second portion. In another example, the width of the one or more pinion gear teeth in the first portion is 32.5% greater than the width of the one or more pinion gear teeth in the second portion. In other examples of the above aspects, the one or more pinion gear teeth have a helical configuration, and the angles of the helical configurations in the first portion and the second portion are the same. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate several principles of the present disclosure. A brief description of the drawings is as follows.

[0010] Figure 1 and Figure 2 is a perspective view of a differential device according to various principles of the present disclosure.

[0011] Figure 3 is a perspective view of a differential device according to various principles of the present disclosure.

[0012] Figure 4 is a schematic diagram of a differential device according to various examples of the present disclosure.

[0013] Figure 5 is a perspective view of a pinion gear according to various principles of the present disclosure.

[0014] Figure 6 is a perspective view of a differential device according to various principles of the present disclosure.

[0015] Figure 7 is a perspective view of a housing member according to various examples of the present disclosure.

[0016] Figure 8 and Fig. 9 is a cross section of a differential device according to various principles of the present disclosure.

[0017] Fig.10 and Fig.11 are two opposing perspective views of a pinion gear of a differential device according to various examples of the present disclosure.

[0018] Figure 12 to Figure 14 is an illustration of a pinion gear of a differential device according to various examples of the present disclosure. DETAILED DESCRIPTION

[0019] Due to the reduced surface pressure bearing capacity caused by the use of low viscosity lubricants (e.g., low viscosity lubricating oils) in the differential mechanism, excessive surface pressure may be generated between the pinion and its corresponding hole due to the use of low viscosity lubricants. Since the friction between the inner surface of the hole and the teeth of the pinion generates high surface pressure, the friction between the teeth of the pinion (or more specifically the tooth ends of the pinion) and the inner surface of the arrangement pinion of the hole may damage the inner surface of the hole. Therefore, by increasing the surface area of ​​the tooth ends of the pinion, for example, the surface pressure at the joint between the inner surface of the hole and the pinion can be reduced. Various examples of the present disclosure include a pinion having teeth with an increased base circle diameter, which makes the teeth of the pinion wider. In other examples, a wider tooth can be provided for a first portion of the pinion, while the rest of the pinion can maintain its original width narrower than the width of the teeth of the first portion. In the example, the teeth along the first length of the pinion axis are wider than the teeth along the remaining length of the pinion, but alternatives are also possible.

[0020] Figure 1 and Figure 2 is a perspective view of a differential device according to various principles of the present disclosure. Figure 1 and Figure 2 , which are two opposite perspective views of the differential device 100, the differential device 100 includes a housing member 130 having an upper cover member 140 and a lower cover member 150. Other details of the differential device 100 will be described below.

[0021] Figure 3 is a perspective view of a differential device according to various principles of the present disclosure. Figure 3, the differential device 100 includes a plurality of pinions 110 and 120 meshing around the same side gear 115, and a fastening hole 135 of a housing member 130. The pinion 120 is different from the pinion 110. For example, for any pinion 110, its teeth have a uniform size along the length of the pinion 110. On the contrary, for any pinion 120, its teeth have different sizes along the length of the pinion. As discussed further below, the size of the teeth at the portion of the pinion 120 that is configured to engage with the side gear 115 through the upper surface of the housing member 130 is greater than the size of the teeth of the pinion 120 that are located away from the upper surface of the housing member 130. Additional details regarding the size of the teeth of the pinion 120 will be discussed further below.

[0022] The side gear 115 and the pinion gears 110 and 120 are coupled to the surface of the housing member 130 of the differential device 100. The housing member 130 has a generally circular shape and includes a plurality of holes 132. The side gear 115 can be arranged along the central axis of a circle formed by the periphery of the housing member 130, and the pinion gears 110 and 120 can be arranged around the side gear 115. In an example, the central axis of each of the pinion gears 110 and 120 can be arranged so that the pinion gears 110 and 120 are arranged equidistantly in the circumferential direction around the side gear 115. For example, the side gear 115 can be configured to mesh with each of the pinion gears 110 and 120 during operation of the differential device 100 so as to cooperate with them. During operation of the differential device 100, the teeth (not shown) of the side gear 115 are configured to mesh with the teeth (not shown) of each of the pinion gears 110 and 120. The differential device 100 further includes an upper cover member 140 and a lower cover member 150 configured to be fixed to the case member 130 via a plurality of bolt fastening members 160 with the pinions 110 and 120 and the side gears 115 therein.

[0023] Figure 4 is a more detailed illustration of the side gear 115 meshing with the plurality of pinion gears 110 and 120 according to various examples of the present disclosure. Figure 4 , the differential device 100 includes a side gear 115 meshing with a plurality of pinion gears 110 and 120. Figure 3 , the side gear 115 and the pinions 110 and 120 are connected to the upper surface of the shell member 130, the side gear 115 can be arranged along the central axis of the circle formed by the upper surface of the shell member 130, and the pinions 110 and 120 are arranged around the side gear 115 in the hole 132 formed in the shell member 130.

[0024] Figure 5 is a perspective view of a side gear and pinion arrangement according to various principles of the present disclosure. Figure 5In the embodiment, the side gears 115 are in a coupled or mating configuration with one or more pinion gears 110 and one or more pinion gears 120. Each pinion gear 110 has helical teeth of the same size thereon along substantially the entire length of the pinion gear 110. Each pinion gear 120 has helical teeth 122 and 125 of different sizes along its length. For example, each pinion gear 120 has helical teeth 125 of a given size along an entire length portion 124 of the pinion gear 120, and has helical teeth 122 of a size larger than the size of the helical teeth 125 along an entire length portion 128 of the pinion gear 120. The two types of pinion gears 110 and 120 are in a mating configuration with the side gears 115.

[0025] Figure 6 is a perspective view of a differential device according to various principles of the present disclosure. Figure 6 In the embodiment, the differential device 100 includes a housing member 130 and a hole 132 (such as Figure 7 In the example, each of the pinion gears 120 includes a plurality of teeth 122, similar to those described above with reference to Figure 5 The pinion gear teeth 122 in question. The side gears 115 are coaxially located within the housing member 130 of the differential device 100. At the surface of the housing member 130, the side gears 115 are configured to mesh or interlock with the pinion gear teeth of the pinion gears 120.

[0026] Figure 7 is a perspective view of a housing member 130 according to various examples of the present disclosure. Figure 7 1, the housing member 130 includes a plurality of holes 132, each of which has an inner surface 134 configured to receive, for example, a pinion gear, such as the pinion gear 120. Due to friction between the inner surface 134 and the pinion gear teeth 122 inserted therein, the inner surface 134 may experience excessive wear during operation of the differential device 100, and the friction area between the teeth 122 of the pinion gear 120 and the inner surface 134 of the hole 132 is highlighted in the area 170. In various examples, due to excessive surface pressure generated between the teeth 122 of the pinion gear 120 and the inner surface 134 of its corresponding hole 132, and due to the use of a low viscosity lubricant therebetween, the portion 170 (corresponding to the interface between the teeth 122 of the pinion gear 120 and the inner surface 134 of the hole 132) experiences wear and overall degradation.

[0027] Figure 8 and Fig. 9 is a cross section of a differential device according to various principles of the present disclosure. Figure 8 and Fig. 9 , and not every component described is depicted in every figure, and Fig. 9 yes Figure 89. The differential 100 includes a side gear 115 and a plurality of pinion gears 110 and 120 configured to mate or interlock with the side gear 115. In examples, each pinion gear 120 includes a first portion 128 along its length at which the pinion teeth 122 are larger than the pinion teeth 125 on the remainder of the length of the pinion gear 120. In contrast, each pinion gear 110 has pinion teeth of the same size along the entire length of the pinion gear 110. In other examples, the side gear 115 includes a lateral surface 118 that faces the pinion gear portion 128 when the side gear 115 and the pinion gear 120 are engaged in a mating configuration. For example, the lateral surface 118 of the side gear 115 does not have any teeth thereon, while other portions of the side gear 115 have side gear teeth 116 thereon. In various examples, the interlocking or mating of the side gear 115 with the pinion gear 120 is achieved by the pinion gear teeth 125 mating or interlocking with the corresponding side gear teeth 116, while the lateral surface 118 of the side gear 115 facing the portion 128 of the pinion gear 120 does not include any teeth thereon. In the area between the lateral surface 118 of the side gear 115 and the portion 128 of the pinion gear 120, there are no side gear teeth.

[0028] The lack of teeth between the lateral surface 118 of the side gear 115 and the portion 128 of the pinion 120 makes it possible to avoid friction between the side gear 115 and the pinion 120 at the portion 128, which can be advantageous because if the lateral surface 118 of the side gear 115 included side gear teeth, the cooperation between such side gear teeth and the larger pinion teeth 122 of the pinion 120 would not be possible and could result in a deterioration in the operation of the differential 100. Therefore, since the lateral surface 118 of the side gear 115 does not include any side gear teeth, the differential 100 can continue to operate normally even in the case where the same pinion 120 includes teeth 122 in one portion 128 that are larger than the pinion teeth 125 included in another portion 124.

[0029] In various examples, for a given pinion 120, the length of the portion 128 including the larger pinion teeth 122 may be in the range of 10%-20% of the total length of the pinion 120. In another example, the length of the portion 128 of the pinion 120 including the larger pinion teeth 122 may be approximately 16% of the total length of the pinion 120.

[0030] In various examples, due to the presence of the larger teeth 122 in the portion 128 of the pinion gear 120, less friction is generated between the pinion gear teeth 122 and the inner surface 134 of the hole 134 into which the pinion gear 120 is inserted. Therefore, even with a low-viscosity lubricant, the surface pressure at the interface between the hole 132 and the pinion gear 120 can be reduced. Therefore, even with a low-viscosity lubricant, the integrity of the inner surface 134 of the hole 132 into which the pinion gear 120 is inserted can be substantially maintained, or can have a longer service life.

[0031] Fig.10 and Fig.11 2 are two relative perspective views of the pinion 120 of the differential device according to various examples of the present disclosure. Fig.10 and Fig.11 In FIG. 1 , the pinion 120 includes a portion 124 at which teeth 125 are smaller than teeth 122 at another portion 128 of the pinion 120 .

[0032] Figure 12 to Figure 14 are various views of the pinion gear 120 according to various examples of the present disclosure. Fig.12 FIG. 1 shows a cross section of a pinion gear 120 according to an example of the present disclosure. Fig.12 In the embodiment, the diameters D1 and D2 at both ends of the pinion 120 are substantially equal to each other. Then, Fig.12 It is also shown that the sizes of teeth 125 and 122 can be different. For example, a tooth 125 of a given size extends over a length L1 of the total length LT of the pinion 120, while a tooth 122 of a size greater than tooth 125 extends over a length L2 on the opposite side of the total length LT of the pinion 120 (which corresponds to region 124). Fig.13 and Fig.14 A side view of the pinion gear 120 is shown according to various examples. Fig.13 A portion of a pinion 120 is shown, the portion comprising teeth 125 having a width w1. Fig.14 A portion of a pinion 120 is shown, which includes a tooth 122 having a width w2. In various examples, the width w2 of the tooth 122 is greater than the width w1 of the tooth 125. In various examples, the width w2 is more than twice the width w1. In the example shown, the width w2 is approximately three times the width w1. Although Fig.12 The larger size teeth 122 are shown extending over a length L2 (corresponding to the portion 128) that is less than the length L1, but in other examples, the length L2 for the smaller size teeth 125 may be equal to or greater than the length L1. The portion 128 or length L2 may account for 10% to 20% of the total length LT of the pinion 120. For another example, the portion 128 accounts for 25% to 33% of the total length LT of the pinion 120. In one example, the portion 128 accounts for 16% of the total length LT of the pinion 120.

[0033] With respect to the size of the teeth 122 as compared to the size of the teeth 125, in various examples, the size of the pinion teeth 122 in the portion 128 is 25%-40% larger than the size of the pinion teeth 125 in the portion 124 of the pinion gear 120, but alternatives are possible. In another example, the size of the pinion teeth 122 in the portion 128 is 32.5% larger than the size of the pinion teeth 125 in the portion 124 of the pinion gear 120, but alternatives are possible. Thus, when using a lower viscosity lubricant, the load carrying capacity can be reduced by up to 24.5%. Alternatively, the gear tooth tip area or outer diameter area of ​​the pinion teeth 125 can be approximately 32.5% larger than the gear tooth tip area of ​​the pinion teeth 122. In other examples, the difference between the gear tooth tip areas of the teeth 125 and 122 can be in the range of 25%-40%.

[0034] The present disclosure describes some examples of the present technology with reference to the accompanying drawings in which only some possible examples are shown. However, other aspects may be embodied in many different forms and should not be construed as limited to the examples set forth herein. Instead, these examples are provided so that the present disclosure is comprehensive and complete and fully conveys the scope of possible examples to those skilled in the art.

[0035] Various modifications and alterations of the disclosure will be apparent to those skilled in the art without departing from the scope and spirit of the disclosure, and it should be understood that the inventive scope of the disclosure is not to be unduly limited to the illustrative examples set forth herein.

Claims

1. A differential device, comprising: a side gear rotatable about an axis, the side gear comprising a plurality of gear teeth extending laterally from the side gear; a housing member rotatable about the axis, the housing member covering the side gear; one or more holes formed in the housing member, the one or more holes extending in a direction parallel to the axis; as well as one or more pinion gears, each of the pinion gears having an upper surface and a length, the pinion gears being inserted into corresponding ones of the one or more holes in a direction parallel to the axis, and the pinion gears having one or more pinion gear teeth extending laterally therefrom; wherein each of the pinion gears is configured to mesh with the side gear via the one or more pinion gear teeth, and Wherein, starting from the upper surface of the pinion gear, the size of the one or more pinion gear teeth along a first length portion of the pinion gear is greater than the size of the one or more pinion gear teeth along a second length portion of the pinion gear.

2. The differential device according to claim 1, wherein: Over the length of the first length portion of the side gear facing the pinion gear, the lateral surface of the side gear is free of gear teeth.

3. The differential device according to claim 1, wherein: The first length portion of the pinion gear is within a range of 10%-20% of a total length of the pinion gear in a direction parallel to the axis.

4. The differential device according to claim 3, wherein: The first length portion of the pinion gear is approximately 16% of the total length of the pinion gear in a direction parallel to the axis.

5. The differential device according to claim 1, wherein: The width of the one or more pinion teeth in the first length portion of the pinion gear is 25%-40% greater than the width of the one or more pinion teeth in the second length portion.

6. The differential device according to claim 5, wherein: The width of the one or more pinion teeth in the first length portion of the pinion gear is 32.5% greater than the width of the one or more pinion teeth in the second length portion.

7. The differential device according to claim 1, wherein: The one or more pinion teeth in the first length portion and the second length portion have a helical configuration, and the angles of the helical configuration in the first length portion and the second length portion are the same.

8. A pinion gear comprising: upper surface; as well as one or more pinion teeth extending transversely from the pinion along a length of the pinion in an axial direction of the pinion, the length comprising: a first portion extending from the upper surface in the axial direction of the pinion; and a second portion extending behind the first portion in the axial direction of the pinion; Wherein, a size of the one or more pinion teeth in the first portion is greater than a size of the one or more pinion teeth in the second portion.

9. The pinion gear according to claim 8, wherein: The length of the first portion of the pinion gear is in the range of 10%-20% of the total length of the pinion gear in the axial direction of the pinion gear.

10. The pinion gear according to claim 9, wherein: The length of the first portion of the pinion gear is approximately 16% of the total length of the pinion gear along the axial direction of the pinion gear.

11. The pinion gear according to claim 8, wherein: The width of the one or more pinion teeth in the first portion is 25%-40% greater than the width of the one or more pinion teeth in the second portion.

12. The pinion gear according to claim 11, wherein: The width of the one or more pinion teeth in the first portion is 32.5% greater than the width of the one or more pinion teeth in the second portion.

13. The pinion gear according to claim 8, wherein: The one or more pinion teeth have a helical configuration, and the angle of the helical configuration in the first portion and the second portion is the same.

14. The differential device according to claim 1, wherein: The outer diameter area of ​​the one or more pinion teeth in the first length portion of the pinion gear is 25%-40% greater than the outer diameter area of ​​the one or more pinion teeth in the second length portion.

15. The pinion gear according to claim 8, wherein: The outer diameter area of ​​the one or more pinion teeth in the first portion is 25%-40% greater than the outer diameter area of ​​the one or more pinion teeth in the second portion.

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