Transaxle watertight structure

Abstract

To provide a transaxle water-stopping structure that can prevent foreign matter such as water and sand from entering the interior through gaps formed in the mating surfaces of a transaxle-side housing case and a power mechanism-side housing case.SOLUTION: A transaxle water-stopping structure 1 comprises: a transaxle-side housing case 10 that houses a power transmission member connected to a power mechanism 3; a power mechanism-side housing case that houses the power mechanism 3 and is connected to the transaxle-side housing case 10; and a water-stopping member 30 attached to the transaxle side housing case 10. A gap 40, which leads to the interior of the transaxle side housing case 10, is formed in a portion of the mating surfaces of the transaxle-side housing case 10 and the power mechanism-side housing case, and the water-stopping member 30 is disposed to cover the gap 40.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a transaxle water-stop structure for a vehicle. [Background Art]

[0002] Conventionally, transaxles are mounted on various types of vehicles (see, for example, Patent Document 1). A power mechanism such as an engine is connected to the transaxle. Specifically, the connection between the transaxle and the power mechanism is achieved by connecting a transaxle-side housing case (transaxle housing) that accommodates the transaxle and a power mechanism-side housing case that accommodates a power mechanism such as an engine via a mating surface. For example, a damper, a flywheel, and the like connected to the power mechanism are accommodated in the transaxle-side housing case.

[0003] Here, in a conventional transaxle, when the mating surface between the transaxle-side housing case and the power mechanism-side housing case is completely sealed, the rotation of the damper, flywheel, or the like causes negative pressure inside the two housing cases, which raises a concern that power transmission efficiency may deteriorate. For this reason, the mating surface between the two housing cases does not use an adhesive (e.g., liquid gasket), and the housing cases are fastened to each other only with bolts. That is, a ventilated gap is formed in the mating surface between the two housing cases. [Prior Art Documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Unexamined Patent Publication No. 2021-104763 [Summary of the Invention] [Problem to be Solved by the Invention]

[0005] Incidentally, there is a demand for transaxles to be used in vehicles equipped with engines of different sizes for general-purpose use. In such cases, it is necessary to connect the transaxle to an engine of a different size. However, when connecting a drive mechanism housing (engine) of a different size to the transaxle housing, there is a problem that the gap between the mating surfaces of the two housings becomes large. When such a large gap occurs, there is a concern that foreign matter such as water and sand may enter the inside of both housings through that gap.

[0006] Therefore, the present invention aims to provide a transaxle watertight structure that can prevent foreign matter such as water and sand from entering the interior through the gap formed at the mating surface of the transaxle-side housing case and the power mechanism-side housing case. [Means for solving the problem]

[0007] (1) The transaxle watertight structure of the present invention, provided to solve the above-mentioned problems, is a transaxle watertight structure for a vehicle, comprising: a transaxle-side housing case housing a power transmission member connected to a power mechanism; a power mechanism-side housing case housing the power mechanism and connected to the transaxle-side housing case; and a watertight member attached to the transaxle-side housing case, wherein a gap is formed in a part of the mating surface of the transaxle-side housing case and the power mechanism-side housing case, leading to the inside of the transaxle-side housing case, and the watertight member is arranged to cover the gap.

[0008] The transaxle waterproofing structure described above can cover the gap formed in a part of the mating surface between the transaxle-side housing case and the power mechanism-side housing case (hereinafter, both are collectively referred to as both housing cases) with a waterproofing member. Therefore, the transaxle waterproofing structure described above can suppress the intrusion of foreign matter such as sand, dust, and moisture through the gap. In addition, because the gap is formed, the transaxle waterproofing structure described above can suppress the increase in internal pressure of both housing cases and the decrease in power transmission efficiency. Furthermore, because the transaxle waterproofing structure described above can cover the gap with a waterproofing member, the versatility of the transaxle is improved. Therefore, the transaxle waterproofing structure described above can be expected to accelerate vehicle development and reduce development costs. In addition, the transaxle waterproofing structure described above may be configured such that the waterproofing member abuts against at least one of the transaxle-side housing case and the power mechanism-side housing case. This allows the transaxle waterproofing structure described above to further suppress the intrusion of foreign matter into both housing cases. Here, various power sources such as engines and drive motors can be used for the power mechanism.

[0009] (2) The transaxle watertight structure of the present invention described above is characterized in that, in the mating surface, the portion where the gap is formed is formed to be thinner than the other mating surfaces where the gap is not formed.

[0010] The transaxle waterproofing structure described above, by having such a configuration, can suppress interference with the differential gear and drive shaft even when the differential gear and drive shaft are positioned close to the gap. Furthermore, since the portion of the transaxle waterproofing structure close to the power transmission member is formed with a thin wall, the gap between the power transmission member and the transaxle housing case can be widened. As a result, the transaxle waterproofing structure can suppress wind noise caused by the rotation of the power transmission member. In addition, even if the gap formed in the thin-walled portion of the mating surface becomes large, the waterproofing member can reliably cover the gap.

[0011] (3) In the transaxle watertight structure of the present invention, the mating surface is preferably characterized in that the portion in close proximity to the power transmission member is formed to be thin.

[0012] The transaxle waterproofing structure described above, by having such a configuration, can suppress interference with the differential gear and drive shaft even when the differential gear and drive shaft are positioned close to the gap. Furthermore, since the portion of the transaxle waterproofing structure close to the power transmission member is formed with a thin wall, the gap between the power transmission member and the transaxle housing case can be widened. As a result, the transaxle waterproofing structure can suppress wind noise caused by the rotation of the power transmission member. In addition, even if the gap formed in the thin-walled portion of the mating surface becomes large, the waterproofing member can reliably cover the gap.

[0013] (4) The transaxle watertight structure of the present invention described above is characterized in that the transaxle-side housing case and the power mechanism-side housing case are formed of a first material, and the watertight member is formed of a second material which has higher rigidity than the first material.

[0014] The transaxle waterproofing structure described above, by having this configuration, can increase the rigidity of both housing cases. As a result, the transaxle waterproofing structure described above can suppress abnormal noises such as rattling and vibrations in both housing cases.

[0015] (5) The transaxle watertight structure of the present invention described above is characterized in that the first material is made of aluminum and the second material is made of iron.

[0016] The transaxle waterproofing structure described above uses aluminum as the primary material, which is widely used for the transaxle-side housing case and the power mechanism-side housing case. Therefore, it can be widely applied to various transaxles and power mechanisms such as engines. As a result, the transaxle waterproofing structure described above can be expected to accelerate vehicle development and reduce development costs. Furthermore, since the transaxle waterproofing structure described above uses iron as the secondary material, it does not incur high costs. In addition, the transaxle waterproofing structure described above can increase the rigidity of both housing cases. As a result, the transaxle waterproofing structure described above can suppress rattling noises and other abnormal noises and vibrations in both housing cases.

[0017] (6) The transaxle watertight structure of the present invention described above is characterized in that the watertight member has a rotation restraining portion in at least a part thereof, and the rotation restraining portion is lockable to at least one of the transaxle side housing case and the power mechanism side housing case.

[0018] The transaxle watertight structure described above, by having this configuration, can suppress rotation and displacement of the watertight member when attaching it to the transaxle-side housing case. This improves the ease of attaching the watertight member.

[0019] (7) The transaxle watertight structure of the present invention described above may be characterized in that the power transmission member is either a damper or a flywheel or both.

[0020] With the above configuration, the transaxle water-stop structure prevents a damper and a flywheel from being exposed to foreign matters such as dust and moisture. Effects of the Invention

[0021] According to the present invention, there can be provided a transaxle water-stop structure capable of suppressing entry of foreign matters such as water and sand into the interior through a gap formed at a mating surface between a transaxle-side housing case and a power mechanism-side housing case. Brief Description of the Drawings

[0022] [Figure 1] 1 is a perspective view of a transaxle water-stop structure according to an embodiment of the present invention. [Figure 2] Fig. 1 is a perspective view of the transaxle water-stop structure in a state where a power mechanism-side housing case is removed. [Figure 3] (a) is a perspective view of a water-stop member constituting the transaxle water-stop structure of the present invention, and (b) is a front view of the water-stop member constituting the transaxle water-stop structure of the present invention. [Figure 4] (c) is a plan view of the water-stop member constituting the transaxle water-stop structure of the present invention, and (d) is a left side view of the water-stop member constituting the transaxle water-stop structure of the present invention. [Figure 5] 1 is a perspective view showing a state where a power transmission member is housed in a transaxle-side housing case used in the transaxle water-stop structure of the present invention. [Figure 6] 1 is an explanatory perspective view showing a state where a water-stop member is removed in the transaxle water-stop structure of the present invention. Mode for Carrying Out the Invention

[0023] The details of the transaxle watertight structure 1 according to one embodiment of the present invention will be described below with reference to the attached drawings. These drawings are schematic diagrams and do not necessarily represent the sizes in precise proportions. Also, in the drawings, similar components are indicated by the same reference numerals. In this embodiment, the case in which the transaxle watertight structure 1 is used in a transaxle 2 mounted on a hybrid vehicle (vehicle) will be described as an example. In this embodiment, the case in which an engine is used as the power mechanism 3 will be described as an example.

[0024] As shown in Figure 1, the transaxle watertight structure 1 comprises a transaxle-side housing case 10 (also referred to as the transaxle housing 10), a power mechanism-side housing case 20 (including one integrally formed with the power mechanism 3), and a watertight member 30. In the following, both the transaxle-side housing case 10 and the power mechanism-side housing case 20 may be collectively referred to as "both housing cases 10, 20".

[0025] As shown in Figures 2 and 5, the transaxle-side housing case 10 houses a damper and flywheel (hereinafter also referred to as power transmission member 4) connected to the power mechanism 3 (also referred to as engine 3, see Figure 1). The power transmission member 4 has an insertion hole 5 formed in its center for inserting an input shaft (not shown).

[0026] The transaxle-side housing case 10 is formed by casting, for example, aluminum (also referred to as the first material). A mating surface 16 is formed between the transaxle-side housing case 10 and the power mechanism-side housing case 20 (see Figure 1). The transaxle-side housing case 10 also has an axial hole 11 through which a drive shaft (not shown) is inserted.

[0027] The mating surface 16 is formed at the protruding end of the peripheral wall 15, which is erected along the axial direction (front direction in the illustration) of the transaxle-side housing case 10. The peripheral wall 15 is formed in a substantially circular shape so as to surround the power transmission member 4. Furthermore, as shown in Figure 5, the peripheral wall 15 has a recess 17 that is recessed toward the inner diameter direction of the input shaft (not shown) in the portion adjacent to the shaft hole 11. As a result, the transaxle watertight structure 1 described above suppresses interference between the transaxle-side housing case 10 and the drive shaft, etc. Details of the recess 17 will be described later.

[0028] The mating surface 16 is formed in a planar shape and is designed to abut against the mating surface (not shown, hereinafter also referred to as the power mechanism side mating surface) of the power mechanism side housing case 20 (see Figure 1), which will be described later. The transaxle side housing case 10 is connected to the power mechanism side housing case 20 by fastening a plurality of bolts 50 while the power mechanism side mating surface and the mating surface 16 are in contact.

[0029] As shown in Figure 1, the power mechanism side housing case 20 is designed to house the power mechanism 3. In this embodiment, the transaxle side housing case 10 is formed by casting, for example, aluminum (also referred to as the first material). The power mechanism side housing case 20 also has a power mechanism side mating surface (not shown) that faces the transaxle side housing case 10.

[0030] The mating surface on the power mechanism side is formed in a planar shape at the protruding end of the peripheral wall 25, which is erected along the axial direction (inward direction in the illustration) of the power mechanism side housing case 20. The peripheral wall 25 is formed in a substantially circular shape. Furthermore, the peripheral wall 25 has a recess 27 that is recessed in the inward direction in the portion facing the recess 17 of the transaxle side housing case 10. As a result, the transaxle watertight structure 1 described above can suppress interference between the power mechanism side housing case 20 and the drive shaft, etc.

[0031] The transaxle-side housing case 10 and the power mechanism-side housing case 20 are connected by fastening them with bolts 50 while the mating surface 16 and the power mechanism-side mating surface are in contact with each other. Here, a gap 40 is formed in the mating surface 16 that leads to the inside of the transaxle-side housing case. The gap 40 will be described below with reference to Figure 6.

[0032] Figure 6 is an explanatory perspective view showing the transaxle watertight structure 1 with the watertight member 30 (described later) removed so that the gap 40 can be seen. Figure 6 also shows the transaxle 2 being used in another vehicle. When the transaxle 2 is used in another vehicle in this way, the shapes of the mating surface 16 and the power mechanism side mating surface are different, so a gap 40 leading to the inside of the transaxle side housing case 10 is formed between the mating surface 16 and the power mechanism side mating surface. The gap 40 is formed to a size that allows the power transmission member 4 to be seen, for example. Therefore, the transaxle watertight structure 1 described above allows the power transmission member 4 to be seen through the gap 40 by removing the watertight member 30 (described later) during maintenance.

[0033] Now, let's explain the recess 17 mentioned above. As shown in Figure 5, the peripheral wall 15 of the transaxle-side housing case 10 is thinner in the vicinity of the recess 17 compared to the parts other than the recess 17. That is, in the mating surface 16, the part where the gap 40 (see Figure 6) is formed is thinner compared to the other mating surfaces 16 where the gap 40 is not formed. In other words, the part of the mating surface 16 that is close to the power transmission member 4 is formed to be thinner.

[0034] Therefore, the transaxle watertight structure 1 described above can suppress interference with the differential gear and drive shaft even when the differential gear and drive shaft are positioned close to the gap 40. Furthermore, since the portion of the transaxle watertight structure 1 that is close to the power transmission member 4 is formed with a thin wall, the gap between the power transmission member 4 and the transaxle housing case 10 can be widened. As a result, the transaxle watertight structure 1 can suppress wind noise caused by the rotation of the power transmission member 4. In addition, even if the gap 40 formed in the thin-walled portion of the mating surface 16 becomes larger, the transaxle watertight structure 1 can be reliably covered by the watertight member 30 described later.

[0035] As shown in Figures 3 and 4, in this embodiment, the water-stopping member 30 is formed in a plate shape using a material (also referred to as the second material) that has higher rigidity than the first material, for example, iron. The water-stopping member 30 is formed by bending a plate-shaped member to match the shape of the gap 40 (see Figure 1). The water-stopping member 30 in this embodiment includes a water-stopping portion 31 that covers the gap 40, and fastening portions 32 and 33 provided at both ends of the water-stopping portion 31.

[0036] As shown in Figures 3(a) and 3(b), the water-stopping portion 31 is formed to follow the shape of the gap 40 so that its outer shape covers the gap 40.

[0037] The fastening portions 32 and 33 are formed by bending both ends of the water-sealing portion 31. Bolt holes 32A and 33A are formed in the fastening portions 32 and 33 for inserting bolts 51. The water-sealing member 30 is fixed by inserting bolts 51 (see Figure 1) through the bolt holes 32A and 33A and screwing them into the screw holes (not shown) of the transaxle-side housing case 10. In this way, the water-sealing member 30 is attached to the transaxle-side housing case 10. In addition, a rotation-preventing portion 32B is formed on at least one side of the fastening portions 32 and 33 (fastening portion 32 in this embodiment).

[0038] The rotation-retaining portion 32B is configured to be lockable to at least one of the transaxle-side housing case 10 and the power mechanism-side housing case 20 (in this embodiment, the transaxle-side housing case 10). In this embodiment, the rotation-retaining portion 32B is formed as two protrusions projecting from the tip side of the fastening portion 32. As shown in Figure 1, when fastened with the bolt 51, the rotation-retaining portion 32B is locked onto the protrusion 13 on the wall surface of the transaxle-side housing case 10, thereby functioning as a rotation stopper. Therefore, the transaxle water-stopping structure 1 described above can prevent the water-stopping member 30 from rotating and shifting position when it is attached to the transaxle-side housing case 10. This improves the ease of attachment of the water-stopping member 30.

[0039] Furthermore, in this embodiment, the water-sealing member 30 is made of a second material (iron) which has higher rigidity than the first material (aluminum) that constitutes the transaxle-side housing case 10 and the power mechanism-side housing case 20, thereby increasing the rigidity of both housing cases 10 and 20. As a result, the transaxle water-sealing structure 1 described above can suppress abnormal noises such as rattling and vibrations of both housing cases 10 and 20.

[0040] The above describes the configuration of the transaxle watertight structure 1 according to one embodiment of the present invention. Next, the effects and advantages of the transaxle watertight structure 1 will be explained.

[0041] The transaxle waterproofing structure 1 described above can cover the gap 40 formed in a part of the mating surface 16 of both housing cases 10 and 20 with the waterproofing member 30. Therefore, the transaxle waterproofing structure 1 described above can prevent foreign matter such as sand, dust, and moisture from entering through the gap 40.

[0042] Furthermore, the transaxle watertight structure 1 described above has a gap 40, which prevents the internal pressure of both housing cases 10 and 20 from increasing and reducing the power transmission efficiency. Also, the transaxle watertight structure 1 described above can cover the gap 40 with the watertight member 30, which improves the versatility of the transaxle 2. Therefore, the transaxle watertight structure 1 described above is expected to accelerate vehicle development and reduce development costs.

[0043] Furthermore, the transaxle watertight structure 1 described above may be configured such that the watertight member 30 contacts at least one of the two housing cases 10 and 20. This further suppresses the intrusion of foreign matter into the housing cases 10 and 20. Thus, with the transaxle watertight structure 1 described above, the damper and flywheel, which serve as power transmission members 4, are not exposed to foreign matter such as sand, dust, and moisture, and thus an improvement in the durability (quality) of the transaxle 2 and power mechanism 3 can be expected.

[0044] Furthermore, the transaxle watertight structure 1 described above is configured such that the first material forming both housing cases 10 and 20 is made of aluminum, and the second material forming the watertight member 30 is made of iron.

[0045] Therefore, the transaxle waterproofing structure 1 described above uses aluminum as the primary material, which is widely used for the transaxle-side housing case 10 and the power mechanism-side housing case 20, and can therefore be widely adapted for various transaxles 2 and power mechanisms such as engines. As a result, the transaxle waterproofing structure 1 described above can be expected to accelerate vehicle development and reduce development costs. Furthermore, since the transaxle waterproofing structure 1 described above uses iron as the secondary material, it does not incur high costs.

[0046] The above describes the configuration and effects of one embodiment of the transaxle watertight structure 1 according to the present invention. However, the transaxle watertight structure 1 of the present invention is not limited to the above-described embodiment and can be modified in various ways.

[0047] In this embodiment, the power mechanism 3 is exemplified as an engine 3 in a hybrid vehicle, but the power mechanism 3 is not limited to this, and various drive sources can be used. For example, the power mechanism 3 may be a drive motor in an electric vehicle. Furthermore, the transaxle watertight structure 1 of the present invention can be used not only in vehicles but also in various devices having a drive source and a transaxle 2. In addition, the power transmission member 4 housed in the transaxle-side housing case 10 is not limited to dampers or flywheels, but can house various power transmission members 4 including transmission-related members. The shape and size of the transaxle-side housing case 10 and the power mechanism-side housing case 20 can also be changed to various types as appropriate. The shape and size of the watertight member 30 can also be changed to various types depending on the shape and size of the gap 40 formed. Furthermore, the gap 40 of the mating surface 16 can be formed in various shapes and sizes depending on the arrangement of the power transmission member 4, etc.

[0048] Furthermore, in this embodiment, the portion of the mating surface 16 where the gap 40 is formed is thinner than the other mating surfaces 16 where the gap 40 is not formed, but this is not limited to this, and the mating surface 16 can be formed to various thicknesses as needed. For example, the entire mating surface 16 may be formed to a uniform thickness. Also, the mating surface on the power mechanism side facing the mating surface 16 can be formed to various thicknesses in the same way as the mating surface 16. In addition, in this embodiment, the portion of the mating surface 16 close to the power transmission member 4 is formed to a thin wall, but as described above, the mating surface 16 and the mating surface on the power mechanism side can be formed to various thicknesses.

[0049] Furthermore, in this embodiment, the first material forming the transaxle-side housing case 10 and the power mechanism-side housing case 20 is made of aluminum, and the second material forming the water-sealing member 30 is made of iron, but this is not limited to this, and various materials can be used for the first and second materials. Also, in this embodiment, the water-sealing member 30 is made of a second material that has higher rigidity than the first material, but this is not limited to this, and the second material may be made of resin or the like that has lower rigidity than the first material.

[0050] Furthermore, in this embodiment, the water-stopping member 30 has a rotation-restricting portion 32B in at least a part of it, but the rotation-restricting portion 32B may be provided only as needed, and it is also possible to have a configuration without a rotation-restricting portion 32B. In addition, the rotation-restricting portion 32B can be formed in various shapes and sizes, and the number provided may not be single but multiple. In addition, the position where the rotation-restricting portion 32B is provided can be set in various positions that can suppress the rotation of the water-stopping member 30, and the position where it is locked to the transaxle-side housing case 10 and the power mechanism-side housing case 20 can also be changed to various positions.

[0051] The above describes various embodiments and modifications of the transaxle watertight structure according to the present invention. However, the present invention is not limited to those exemplified in the embodiments and modifications described above, and it will be readily apparent to those skilled in the art that other embodiments may exist in the spirit and teachings thereof, without departing from the scope of the claims. [Industrial applicability]

[0052] The transaxle watertight structure of the present invention can be used in transaxles of various vehicles (e.g., gasoline vehicles, hybrid vehicles, electric vehicles, etc.). [Explanation of Symbols]

[0053] 1: Transaxle watertight structure 2: Transaxle 3: Power mechanism (engine) 4: Power transmission member 10: Transaxle side housing case (transaxle housing, housing case) 16: Machining surface 20: Power mechanism side housing case (housing case) 30: Water-stopping component 32B: Rotation restraint unit 40: Gap

Claims

1. A transaxle watertight structure in a vehicle, A transaxle-side housing case that houses the power transmission member connected to the power mechanism, A power mechanism side housing case that houses the aforementioned power mechanism and is connected to the transaxle side housing case, A water-sealing member attached to the transaxle side housing case, It is equipped with, A gap is formed in a portion of the mating surface between the transaxle-side housing case and the power mechanism-side housing case, which leads to the inside of the transaxle-side housing case. A transaxle watertight structure characterized in that the watertight member is arranged to cover the gap.

2. The transaxle watertight structure according to Claim 1, characterized in that, in the mating surfaces within the same case of at least one of the transaxle-side housing case and the power mechanism-side housing case, the mating surface corresponding to the portion where the gap is formed is formed to be thinner than the mating surface corresponding to the portion where the gap is not formed.

3. The transaxle-side housing case and the power mechanism-side housing case are formed from the first material. The transaxle watertight structure according to claim 1 or 2, characterized in that the watertight member is formed of a second material which has higher rigidity than the first material.

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