Transaxle

Abstract

To provide a space-saving transaxle capable of suppressing cracking of a case.SOLUTION: A transaxle 30 according to the present disclosure houses at least a rotary electric machine and gears in a case. A case 35 of the transaxle 30 comprises a first boss part 31 that protrudes toward a vehicle member side and provided at an upper portion and a second boss part 32 that protrudes toward the vehicle member side and provided at a lower portion, on a surface that contacts the vehicle member when it is bent due to a collision load. The vehicle member contacts the first boss part 31 or an upper part 321 of the second boss part before a lower part 322 of the second boss part.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to transaxles. [Background technology]

[0002] Patent Document 1 discloses a transaxle that is highly robust against collisions and can prevent cracks from occurring in the cover. The transaxle disclosed in Patent Document 1 has ribs in a grid pattern on the outer surface to prevent contact with the front side members. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2020-045981 Summary of the Invention [Problem to be solved by the invention]

[0004] However, space-saving measures have been considered for units including transaxles. However, providing ribs as in the transaxle disclosed in Patent Document 1 occupies space, making it difficult to save space.

[0005] The present disclosure has been made in consideration of the above circumstances, and provides a transaxle that is space-saving and can suppress cracking of the case. [Means for solving the problem]

[0006] The transaxle according to the present disclosure comprises: A transaxle in which at least a rotating electric machine and a gear are housed in a case, The case is On the surface where the vehicle member bent under the impact load comes into contact, a first boss portion provided upward and protruding toward the vehicle member; a second boss portion that projects toward the vehicle member and is provided downward, The vehicle member abuts against the first boss portion or the upper portion of the second boss portion before the lower portion of the second boss portion abuts against the first boss portion or the upper portion of the second boss portion.

[0007] In the transaxle according to the present disclosure, the vehicle component abuts against the first boss portion or the upper portion of the second boss portion before the lower portion of the second boss portion, which allows the transaxle according to the present disclosure to save space and prevent cracking of the case.

[0008] The first boss portion may protrude further toward the vehicle member than the second boss portion. Even with this configuration, space can be saved and cracking of the case can be prevented.

[0009] The second boss may have at least a portion of its upper part protruding further than its lower part. Even with this configuration, it is possible to save space and prevent the case from cracking.

[0010] The second boss portion may have a tapered shape that protrudes toward the upper portion. Even with this configuration, it is possible to save space and prevent the case from cracking.

[0011] The transaxle according to the present disclosure comprises: A transaxle in which at least a rotating electric machine and a gear are housed in a case, The case is a boss portion provided below a surface against which a vehicle member bent by a collision load abuts, the boss portion protruding toward the vehicle member; and a cushioning portion that cushions the impact by being pushed in by the vehicle member when the vehicle member abuts against the boss portion.

[0012] In the transaxle according to the present disclosure, when a vehicle component abuts against the boss portion, the vehicle component pushes in to absorb the impact, thereby saving space and reducing cracking of the case.

[0013] The present disclosure makes it possible to provide a transaxle that is space-saving and can prevent cracking of the case. [Brief explanation of the drawings]

[0014] [Figure 1] 10A and 10B are diagrams illustrating a state in which the transaxle and a vehicle member come into contact with each other during a vehicle collision. [Figure 2] FIG. 10 is a diagram showing a part of a case of a transaxle according to a comparative example. [Figure 3] 1 is a diagram showing a part of a case of a transaxle according to a first embodiment. [Figure 4] FIG. 10 is a diagram showing a part of a case of a transaxle according to a modified example. [Figure 5] FIG. 10 is a diagram showing a portion of a case of a transaxle according to another modified example. [Figure 6] FIG. 10 is a view showing a part of a case of a transaxle according to a second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0015] The present disclosure will be described below through embodiments of the invention, but the invention according to the claims is not limited to the following embodiments. Furthermore, not all of the configurations described in the embodiments are necessarily essential means for solving the problems. For clarity of explanation, the following description and drawings have been omitted and simplified as appropriate. In each drawing, the same elements are given the same reference numerals, and repeated explanations are omitted as necessary. Naturally, the right-handed xyz Cartesian coordinate system shown in the drawings is for the convenience of explaining the positional relationships of the components. Normally, the positive direction of the z axis is vertically upward, and the xy plane is the horizontal plane.

[0016] (Embodiment 1) <Transaxle according to comparative example> First, a transaxle according to a comparative example will be described with reference to Figures 1 and 2. Figure 1 is a diagram showing the state in which the transaxle and vehicle components abut against each other during a vehicle collision. Figure 2 is a diagram showing a portion of the case of the transaxle according to the comparative example. In Figures 1 and 2, the positive direction of the z-axis corresponds to the upward direction, and the negative direction of the z-axis corresponds to the downward direction. In Figure 1, each side of case 15 of transaxle 10 is arranged so as to be parallel to the x-axis or y-axis.

[0017] The state of contact between the transaxle and vehicle components when the vehicle collides will be described below. As shown in FIG. 1, when the vehicle receives a collision load, vehicle component 60 bends and contacts transaxle 10. Vehicle component 60 is, for example, a front side member. When the vehicle collides, case 15 of transaxle 10 cracks, resulting in a safety hazard. The contact points between transaxle 10 and vehicle component 60 will be described later.

[0018] A transaxle according to a comparative example will now be described. As shown in Fig. 1, transaxle 10 houses at least a rotating electric machine 13 and gears 14 in case 15. In the example shown in Fig. 1, transaxle 10 includes one rotating electric machine 13 and two gears 14.

[0019] Referring to Figure 2, the boss portion of transaxle 10 according to the comparative example will be described. Case 15 of transaxle 10 has first boss portion 11 and second boss portion 12. First boss portion 11 protrudes toward vehicle member 60 and is provided upward (on the positive z-axis side) on the surface that contacts vehicle member 60 that has been bent due to a collision load. Second boss portion 12 protrudes toward vehicle member 60 and is provided downward (on the negative z-axis side) on the surface that contacts vehicle member 60 that has been bent due to a collision load.

[0020] Furthermore, the first boss portion 11 and the second boss portion 12 have the same length of protrusion from the case 15. More specifically, as shown in Fig. 2, the tip end of the first boss portion 11 and the tip end of the second boss portion are both located on the reference line C1.

[0021] The following describes the contact points between the transaxle 10 and the vehicle member 60 when the vehicle collides. As shown in Figure 1, the vehicle member 60 is located further forward of the vehicle (on the negative x-axis and negative y-axis sides) than the transaxle 10. As a result, when the vehicle collides, the first boss portion 11 and the second boss portion 12 come into contact with the vehicle member 60, as shown in Figure 1.

[0022] Here, the rigidity of the root portion G1 and corner portion G2 of the transaxle 10 will be described with reference to Figure 2. The root portion G1 is the root portion of the second boss portion 12. The corner portion G2 is the corner portion of the case 15 on the second boss portion 12 side. The root portion G1 has low rigidity and is subject to large deformation upon impact. The corner portion G2 has high rigidity and is subject to small deformation upon impact.

[0023] For this reason, when the lower portion 122 of the second boss portion 12 shown in Fig. 2 comes into contact with the vehicle component 60, stress is concentrated on the lower portion 122 of the second boss portion 12 rather than on the upper portion 121 of the second boss portion 12. The stress is then concentrated on the base portion G1. This causes the case 15 to crack.

[0024] The upper portion 121 of the second boss portion 12 refers to the portion of the second boss portion that is closer to the positive z-axis direction than the center of the second boss portion in the z-axis direction. The lower portion 122 of the second boss portion 12 refers to the portion of the second boss portion that is closer to the negative z-axis direction than the center of the second boss portion in the z-axis direction. The same applies to the upper and lower portions of the second boss portion 12 described below.

[0025] Thus, the transaxle 10 according to the comparative example has first boss portion 11 and second boss portion 12 that have the same length of protrusion from case 15. In the transaxle 10 according to the comparative example, stress is concentrated on lower portion 122 of second boss portion 12, causing case 15 to crack.

[0026] <Transaxle> Next, a description will be given of the transaxle according to embodiment 1. Fig. 3 is a diagram showing a portion of the case of the transaxle according to embodiment 1. Although not shown in Fig. 3, transaxle 20 according to embodiment 1 houses at least rotating electric machine 13 and gear 14 in case 15, similar to transaxle 10 according to the comparative example shown in Fig. 1.

[0027] The boss portion of the transaxle according to the first embodiment will be described with reference to Figure 3. Case 25 of transaxle 20 includes first boss portion 21 and second boss portion 22. First boss portion 21 protrudes toward vehicle member 60 and is provided upward (on the positive z-axis side) on the surface that contacts vehicle member 60 that has been bent due to a collision load. Second boss portion 22 protrudes toward vehicle member 60 and is provided downward (on the negative z-axis side) on the surface that contacts vehicle member 60 that has been bent due to a collision load.

[0028] Furthermore, the first boss portion 21 and the second boss portion 22 have different lengths of protrusion from the case 15. More specifically, as shown in FIG. 3 , the tip of the first boss portion 21 is located on the negative x-axis side of the reference line C2. On the other hand, the tip of the second boss portion 22 is located on the reference line C2. Thus, in the transaxle 20, the length of protrusion of the first boss portion 21 from the case 15 is longer than the length of protrusion of the second boss portion 22 from the case 15. In other words, the first boss portion 21 protrudes closer to the vehicle member 60 than the second boss portion 22.

[0029] The following describes the contact points between the transaxle 20 and the vehicle member 60 when the vehicle collides. As shown in Figure 3, the first boss portion 21 protrudes further toward the vehicle member 60 than the second boss portion 22, so the vehicle member 60 contacts the first boss portion 21 before the lower portion 222 of the second boss portion 22. This allows stress when the vehicle collides to be distributed to the first boss portion 21 and the second boss portion 22. This prevents stress from concentrating on the lower portion 222 of the second boss portion 22, thereby preventing the case 25 from cracking.

[0030] Furthermore, because transaxle 20 has a configuration in which case 25 is provided with first boss portion 21 and second boss portion 22, there is no need to provide collision prevention materials such as ribs on the outside of transaxle 20. As a result, transaxle 20 is space-saving and can prevent cracking of the case.

[0031] In this way, in transaxle 20, first boss portion 21 protrudes further toward vehicle member 60 than second boss portion 22. This causes vehicle member 60 to abut against first boss portion 21 before lower portion 222 of second boss portion 22, thereby saving space and preventing cracking of the case.

[0032] <Transaxle according to modified example> Next, a transaxle according to a modified example will be described. Figure 4 is a diagram showing a portion of the case of a transaxle according to a modified example. A transaxle 30 according to a modified example differs from transaxle 20 in the configuration of the first boss portion and the second boss portion, but the configuration is otherwise the same, so the description will focus on the first boss portion and the second boss portion.

[0033] Case 35 of transaxle 30 has a first boss portion 31 and a second boss portion 32. First boss portion 31 protrudes toward vehicle member 60 and is provided upward (on the positive z-axis side) on the surface that contacts vehicle member 60 that has been bent due to a collision load. Second boss portion 32 protrudes toward vehicle member 60 and is provided downward (on the negative z-axis side) on the surface that contacts vehicle member 60 that has been bent due to a collision load.

[0034] As shown in Fig. 4, in transaxle 30, second boss portion 32 has upper portion 321 that protrudes more toward the vehicle component side than lower portion 322. More specifically, the tip of second boss portion upper portion 321 is located on reference line C3. Meanwhile, the tip of second boss portion lower portion 322 is located on the positive x-axis direction side of reference line C3. In addition, the tip of first boss portion 21 is located on reference line C3.

[0035] Thus, in transaxle 30, the length by which upper portion 321 of second boss portion 32 protrudes from case 35 is longer than the length by which lower portion 322 of second boss portion 32 protrudes from case 35. In other words, in transaxle 30, second boss portion 32 has a stepped shape. The length by which first boss portion 31 protrudes from case 35 is the same as the length by which upper portion 321 of second boss portion protrudes from case 35.

[0036] The following describes the contact points between the transaxle 30 and the vehicle member 60 when the vehicle collides. As shown in Figure 4, the first boss portion 31 and the upper portion 321 of the second boss portion protrude further toward the vehicle member 60 than the lower portion 322 of the second boss portion. As a result, the vehicle member 60 contacts the upper portion 321 of the second boss portion before the lower portion 322 of the second boss portion. This prevents stress from concentrating on the lower portion 322 of the second boss portion 32, thereby preventing the case 35 from cracking.

[0037] In this way, in transaxle 30, upper portion 321 of second boss portion protrudes toward vehicle member 60 more than lower portion 322 of second boss portion. This allows vehicle member 60 to abut against upper portion 321 of second boss portion before lower portion 322 of second boss portion, thereby saving space and preventing cracking of the case.

[0038] 3, it is sufficient that at least a portion of the upper portion 321 protrudes further than the lower portion 322. In other words, it is sufficient that the upper portion 321 of the second boss portion has a shape that allows it to abut against the vehicle member 60 before the lower portion 322 of the second boss portion 32 abuts against the vehicle member 60.

[0039] <Transaxle according to modified example> Next, a transaxle according to another modified example will be described. Fig. 5 is a diagram showing a portion of the case of a transaxle according to another modified example. A transaxle 40 according to another modified example differs from transaxle 30 in the configuration of the second boss portion, but the other configurations are the same, so the description will focus on the second boss portion.

[0040] As shown in FIG. 5, in the transaxle 40, the second boss portion 42 has a tapered shape that protrudes upward (toward the positive z-axis direction). More specifically, the upper end (positive z-axis direction) of the upper portion 421 of the second boss portion 42 is located on the reference line C4. On the other hand, the lower end (negative z-axis direction) of the lower portion 422 of the second boss portion 42 is located on the positive x-axis direction side of the reference line C4. That is, in the x-z plane view, the second boss portion 42 has a tapered shape with a negative slope from above the tip of the upper portion 421 to below the tip of the lower portion 422. In addition, the tip of the first boss portion 41 is located on the reference line C3.

[0041] Thus, in transaxle 40, the length by which second boss portion 32 protrudes from case 45 increases as it approaches the upper side (positive z-axis direction). The length by which first boss portion 41 protrudes from case 45 is the same as the length by which upper portion 421 protrudes from case 45 above the tip end (positive z-axis direction).

[0042] The following describes the contact points between transaxle 40 and vehicle member 60 when the vehicle collides. As shown in FIG. 4, second boss portion 42 has a tapered shape that protrudes upward (toward the positive z-axis direction). This causes vehicle member 60 to contact upper portion 421 of second boss portion before lower portion 422 of second boss portion 42. This prevents stress from concentrating on lower portion 422 of second boss portion 42, thereby preventing case 45 from cracking.

[0043] Thus, in transaxle 40, second boss portion 42 has a tapered shape that protrudes upward (toward the positive z-axis direction). This allows vehicle member 60 to abut against upper portion 421 of second boss portion before lower portion 422 of second boss portion, thereby saving space and preventing cracking of the case.

[0044] As described above, in transaxles 20, 30, and 40, vehicle member 60 abuts against the upper part of the first boss portion or the upper part of the second boss portion before abutting against the lower part of the second boss portion. This configuration saves space and prevents cracking of the case.

[0045] It can also be said that the position of stress concentration is controlled so that pressure does not concentrate on the lower part of the second boss in transaxles 20, 30, and 40. In this way, the shape of the first boss or second boss that abuts against the vehicle component is changed in transaxles 20, 30, and 40 to control the position of stress concentration, thereby saving space and preventing cracking of the case.

[0046] Furthermore, the transaxles 20, 30, and 40 are superior in terms of weight reduction because they only require changing the shape of the first boss portion or the second boss portion that abuts against the vehicle components. In addition, the transaxles 20, 30, and 40 can be realized in a space-saving manner, so they can be installed in all types of vehicles, including hybrid vehicles and hydrogen engine vehicles.

[0047] Naturally, a transaxle having first boss portion 21 of transaxle 20 and second boss portion 32 of transaxle 30 can similarly save space and prevent cracking of the case. Furthermore, a transaxle having first boss portion 21 of transaxle 20 and second boss portion 42 of transaxle 40 can similarly save space and prevent cracking of the case.

[0048] (Embodiment 2) <Transaxle> A transaxle according to embodiment 2 will now be described. Fig. 6 is a diagram showing a portion of the case of the transaxle according to embodiment 2. Although not shown in Fig. 6, transaxle 50 according to embodiment 2 houses at least rotating electric machine 13 and gear 14 in case 15, similar to transaxle 10 according to the comparative example shown in Fig. 1.

[0049] 6 shows the deformation of transaxle 50 before and after a vehicle collision. The left side of FIG. 6 shows transaxle 50 before the vehicle collision, and the right side of FIG. 6 shows transaxle 50 after the vehicle collision.

[0050] The first boss portion 51 and the second boss portion 52 of the transaxle 50 are similar to the first boss portion 11 and the second boss portion 12 of the transaxle 10 according to the comparative example shown in Figure 1, and therefore a description thereof will be omitted. Here, the description will focus on the relaxation portion 80.

[0051] When the vehicle member 60 (see FIG. 1) comes into contact with the second boss portion 52, the cushioning portion 80 cushions the impact by being pushed in by the vehicle member 60. In the example shown in FIG. 6, the cushioning portion 80 is configured to have low rigidity and bend in the x-axis direction.

[0052] The shape of the relaxation portion 80 is not limited to the U-shape shown in Fig. 6, and may be any shape that allows it to bend in the x-axis direction. Furthermore, the relaxation portion 80 is preferably made of a material with a low Young's modulus. Furthermore, as shown in Fig. 6, the relaxation portion 80 is preferably provided below the second boss portion 52 (on the negative z-axis side), but is not limited to this, and may be provided below the second boss portion 52 (on the negative z-axis side) and above the first boss portion 51 (on the positive z-axis side).

[0053] The transaxle 10 shown in FIG. 2 is compared with the transaxle 50 shown in FIG. 6. As mentioned above, in the transaxle 10 shown in FIG. 2, the root portion G1 has low rigidity and undergoes large deformation upon impact. The corner portion G2 has high rigidity and undergoes small deformation upon impact. For this reason, when the transaxle 10 shown in FIG. 2 comes into contact with a vehicle member 60, stress is concentrated on the lower portion 122 of the second boss portion 12 rather than on the upper portion 121 of the second boss portion 12. Thus, stress is concentrated on the root portion G1. This causes the case 15 to crack.

[0054] 2, in the case of transaxle 50, when the vehicle collides, lower portion 522 of second boss portion 52 comes into contact with vehicle member 60. Then, lower portion 522 of second boss portion 52 is pushed toward the positive x-axis direction while maintaining contact with vehicle member 60.

[0055] The relaxation portion 80 bends in the x-axis direction as the lower portion 522 of the second boss portion 52 is pressed in by the vehicle member 60. That is, the relaxation portion 80 bends in the x-axis direction as shown from the state on the left side of Fig. 6 to the state on the right side of Fig. 6. This makes it possible to prevent stress from concentrating on the lower portion 522 of the second boss portion 52, thereby preventing the case 55 from cracking.

[0056] In this way, transaxle 50 is provided with buffer portion 80 that buffers the impact by being pushed in by the vehicle member when the vehicle member abuts against second boss portion 52. This prevents stress from concentrating on lower portion 522 of second boss portion 52, thereby saving space and preventing cracking of case 55.

[0057] The present disclosure is not limited to the above-described embodiments, and can be modified as appropriate within the scope of the present disclosure. [Explanation of symbols]

[0058] 10, 20, 30, 40, 50 transaxle 11, 21, 31, 41, 51 First boss section 12, 22, 32, 42, 52 Second boss section 13 Rotating Electric Machine 14 gears 15, 25, 35, 45, 55 cases 60 Vehicle parts 80 Relaxation section 121, 221, 321, 421, 521 upper 122, 222, 322, 422, 522 bottom G1 base G2 Corner

Claims

1. A transaxle in which at least a rotating electric machine and a gear are housed in a case, The case is On the surface where the vehicle member bent under the impact load comes into contact, a first boss portion provided upward and protruding toward the vehicle member; a second boss portion that projects toward the vehicle member and is provided downward, The vehicle member abuts against the first boss portion or the upper portion of the second boss portion before the lower portion of the second boss portion abuts against the first boss portion or the upper portion of the second boss portion. Transaxle.

2. The first boss portion protrudes toward the vehicle member side more than the second boss portion. The transaxle of claim 1 .

3. At least a part of an upper portion of the second boss portion protrudes more than a lower portion thereof.

3. The transaxle according to claim 1 or 2.

4. The second boss portion has a tapered shape that protrudes upward.

3. The transaxle according to claim 1 or 2.

5. A transaxle in which at least a rotating electric machine and a gear are housed in a case, The case is a boss portion provided below a surface against which a vehicle member bent by a collision load abuts, the boss portion protruding toward the vehicle member; a cushioning portion that cushions impact by being pushed in by the vehicle member when the vehicle member abuts against the boss portion; Equipped with Transaxle.

Images