Protective cover
The protective cover with fastening parts and edge notches addresses stress concentration issues in L-shaped cantilevered structures, ensuring durability by distributing stress evenly.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- TOYOTA JIDOSHA KK
- Filing Date
- 2024-11-06
- Publication Date
- 2026-05-19
AI Technical Summary
Protective covers for rotating members extending in one axial direction, when made L-shaped with two tip portions, face damage due to localized stress concentration from bending loads, as traditional cantilevered structures lack effective stress distribution.
The protective cover is designed with fastening parts at both ends and notches at the edge end on the cantilevered side to suppress localized stress concentration, ensuring it is attached in a cantilevered manner.
The design effectively distributes stress, preventing damage such as cracking by reducing localized stress concentration, thereby enhancing the cover's durability.
Smart Images
Figure 2026082149000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to an L-shaped protective cover that is used to protect a rotating member extending in the axial direction, is composed of a plate-like body, and has two tip portions when developed in a direction perpendicular to the plate thickness direction of the plate-like body.
Background Art
[0002] A protective cover that is attached in a cantilever manner with one end fixed to a transfer and the other end being a free end is known. For example, the protective cover described in Patent Document 1 is such a cover. The protective cover described in Patent Document 1 is formed to extend along one axis, has a semicircular cross-sectional shape with half of the circumferential direction being open, and is supported by providing a bearing between one end fixed to the transfer and the other end which is the free end.
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0004] By the way, there may be a case where a protective cover used to protect a rotating member extending in one axial direction is made into an L-shape having two tip portions when the protective cover is composed of a plate-like body and developed in a direction perpendicular to the plate thickness direction of the plate-like body. In such a case, a structure supported by a bearing as in the protective cover of Patent Document 1 cannot be adopted. As a result, in a protective cover having a structure attached in a cantilever manner, there is a risk that the protective cover may be damaged due to local concentration of stress caused by bending load.
[0005] The present invention was made against the above circumstances, and its objective is to provide a protective cover that is cantilevered and can suppress damage caused by localized stress concentration due to bending load. [Means for solving the problem]
[0006] The gist of the present invention is an L-shaped protective cover used to protect a rotating member extending in the axial direction, which is made of a plate-like body and has two ends when unfolded in a direction perpendicular to the thickness direction of the plate-like body, wherein (a) fastening parts are provided at each of the two ends of the protective cover, (b) the protective cover is cantilevered when the fastening parts are fastened, and (c) the edge end of the protective cover on the cantilevered side is provided with a notch to suppress localized stress concentration due to bending load generated in a cross section perpendicular to the straight line connecting the fastening parts. [Effects of the Invention]
[0007] According to the protective cover of the present invention, (a) fastening portions are provided at each of the two tip portions of the protective cover, (b) the protective cover is attached in a cantilevered manner by fastening the fastening portions, and (c) notches are provided at the edge end of the protective cover on the cantilevered attachment side to suppress localized stress concentration due to bending loads occurring in a cross section perpendicular to the straight line connecting the fastening portions. In this way, in a protective cover with a cantilevered attachment structure, the provision of notches suppresses localized stress concentration due to bending loads, thereby suppressing damage to the protective cover. [Brief explanation of the drawing]
[0008] [Figure 1] This figure illustrates the schematic configuration of a vehicle on which a heat-shielding member according to Embodiment 1 of the present invention is mounted. [Figure 2]This diagram illustrates how the heat shielding member is attached to the transfer case via two brackets. [Figure 3] Figure 2 is a perspective view of the heat shielding member as seen in the direction of arrow III. [Figure 4] Figure 3 illustrates the shape of the notches in the heat-shielding member shown and the stress due to bending load, where (a) is a schematic diagram of the heat-shielding member shown in Figure 3 when unfolded in a direction perpendicular to the plate thickness direction, and (b) is a diagram illustrating the stress due to bending load generated at the location where the notches are provided. [Figure 5] This is a schematic diagram showing the heat-shielding member according to Embodiment 2 of the present invention when it is unfolded in a direction perpendicular to the plate thickness direction. [Figure 6] This is a schematic diagram showing the heat-shielding member according to Embodiment 3 of the present invention when it is unfolded in a direction perpendicular to the plate thickness direction. [Figure 7] This is a schematic diagram showing the heat-shielding member according to Embodiment 4 of the present invention when it is unfolded in a direction perpendicular to the plate thickness direction. [Modes for carrying out the invention]
[0009] Hereinafter, each embodiment of the present invention will be described in detail with reference to the drawings. Note that in each embodiment, the drawings have been simplified or modified as appropriate, and the dimensional ratios and shapes of each part are not necessarily depicted accurately. [Examples]
[0010] Figure 1 is a diagram illustrating the schematic configuration of a vehicle 10 on which a heat-shielding member 70 according to Embodiment 1 of the present invention is mounted.
[0011] Vehicle 10 is equipped with an engine 12 as a power source for driving, a pair of front wheels 14 (hereinafter simply referred to as "front wheels 14"), a pair of rear wheels 16 (hereinafter simply referred to as "rear wheels 16"), and a power transmission device 18 that transmits power from the engine 12 to the front wheels 14 and rear wheels 16, respectively. For example, the rear wheels 16 are the main drive wheels, which are driven wheels in both two-wheel drive and four-wheel drive modes. For example, the front wheels 14 are the secondary drive wheels, which are driven wheels in two-wheel drive mode and drive wheels in four-wheel drive mode. Vehicle 10 is a four-wheel drive vehicle based on the FR (front engine, rear drive) system.
[0012] The engine 12 is a well-known internal combustion engine. The power transmission device 18 includes a transmission 22 in the power transmission path between the engine 12 and the transfer case 26, and the transmission 22 has a well-known configuration. The transfer case 26 is a well-known front and rear wheel power distribution device that distributes all of the engine 12's power to the rear wheels 16, or distributes the engine 12's power to the front wheels 14 and the rear wheels 16, respectively. The power transmission device 18 includes, in order from the transfer case 26 side, a constant velocity coupling 30, a front propeller shaft 32, a constant velocity coupling 34, a front differential gear 36, and a pair of front drive shafts 38 in the power transmission path between the transfer case 26 and the front wheels 14, and these have a well-known configuration. The power transmission device 18 includes, in order from the transfer case 26 side, a constant velocity coupling 40, a rear propeller shaft 42, a constant velocity coupling 44, a rear differential gear 46, and a pair of rear drive shafts 48 in the power transmission path between the transfer case 26 and the rear wheels 16, and these are well-known configurations. The constant velocity coupling 40 extends in the direction of axis C. Axis C is the rotational centerline of the rotating shaft connected from the transfer case 26 to the constant velocity coupling 40.
[0013] The transfer case 26 includes, for example, an engagement clutch (not shown) that can disconnect and reconnect power transmission between the transfer case 26 and the front propeller shaft 32. When this engagement clutch is disengaged, the vehicle 10 can operate in two-wheel drive mode. When the engagement clutch is connected, the vehicle 10 can operate in four-wheel drive mode.
[0014] The exhaust pipe 50 of the engine 12 is provided so as to extend in the longitudinal direction of the vehicle 10 below the vehicle, for example, at a predetermined distance from the constant velocity coupling 40 that connects the transfer case 26 and the rear propeller shaft 42. The high-temperature combustion gases output from the engine 12 are discharged through the exhaust pipe 50. The exhaust pipe 50 is equipped with, for example, a well-known catalytic converter 52. Because the catalytic converter 52 has a larger diameter than the exhaust pipe 50, it is more likely to be positioned closer to the constant velocity coupling 40 than the exhaust pipe 50. The catalytic converter 52 is controlled to operate within a predetermined operating temperature range that ensures efficient purification without damaging the catalytic converter 52.
[0015] The transfer case 26 comprises a transfer case 26c and a transfer body 26b housed within the transfer case 26c. A heat shield member 70 is attached to the outer circumference of the transfer case 26c. The heat shield member 70 is a heat insulator used to shield the constant velocity coupling 40 from radiant heat by shielding it from radiant heat from the exhaust pipe 50 (hereinafter including the catalytic converter 52). The constant velocity coupling 40 is equipped with a boot to prevent foreign matter from entering the constant velocity coupling 40 or to prevent lubricating oil from leaking out of the constant velocity coupling 40. This boot is made of an elastic material such as synthetic rubber to allow for elastic deformation and is thermally weaker than the heat shield member 70. The heat shield member 70 is formed, for example, by press-forming a metal plate that is in the shape of a plate. In the radial direction centered on axis C, the heat shield member 70 is positioned between the exhaust pipe 50 and the constant velocity coupling 40. The constant velocity coupling 40 corresponds to the "rotating member" in this invention. The heat shield member 70 corresponds to the "protective cover" in this invention. Since the radiant heat from the exhaust pipe 50 is blocked or reflected by the heat shield member 70, for example, the temperature rise of the constant velocity coupling 40 caused by the exhaust pipe 50 is suppressed. Furthermore, for example, when the vehicle is running, the constant velocity coupling 40 is cooled by being exposed to the outside air in the parts of the constant velocity coupling 40 that are not covered by the heat shield member 70.
[0016] The heat shield member 70 is attached to the transfer case 26c of the transfer 26 via the brackets 64 and 66. The brackets 64 and 66 are well-known components that serve as connectors for attaching and supporting the heat shield member 70 to the transfer 26. The brackets 64, 66 are made of, for example, metal. The heat shield member 70 is fixed to the transfer 26 via the bracket 64 by the fastener 94 and is also fixed to the transfer 26 via the bracket 66 by the fastener 96.
[0017] FIG. 2 is a diagram for explaining a state in which the heat shield member 70 is attached to the transfer 26 via two brackets 64 and 66, respectively. In FIG. 2, the transfer 26 is shown by a dashed line. FIG. 3 is a perspective view of the heat shield member 70 as viewed in the direction of arrow III shown in FIG. 2.
[0018] The heat shield member 70 is composed of a plate-like body. The heat shield member 70 is bent, for example, along a fold line FL (see FIG. 4) parallel or substantially parallel to the axis C. Thereby, the heat shield member 70 is configured to cover a part of the circumferential direction centered on the axis C. That is, the heat shield member 70 covers a part of the circumferential direction of the constant velocity joint 40. When the heat shield member 70 is unfolded in a direction perpendicular to the plate thickness direction of the plate-like body, the heat shield member 70 has an L-shape (see FIG. 4) having two tip portions 74 and 76 extending from the base portion 72 in directions substantially perpendicular to each other. Hereinafter, the "plate thickness direction of the plate-like body" will be simply referred to as the "plate thickness direction". [[ID=X]]
[0019] [[ID=X]] One of the two tip portions 74 and 76, i.e., the tip portion 74, is provided with one fastening portion 84 in which a fastening hole is formed. The other of the two tip portions 74 and 76, i.e., the tip portion 76, is provided with one fastening portion 86 in which a fastening hole is formed. That is, each of the two tip portions 74 and 76 is provided with one fastening portion. The bracket 64 is fixed to the transfer 26 by, for example, a bolt not shown. The bracket 66 is fixed to the transfer 26 by, for example, a bolt 90. A bolt 94b that passes through the fastening portion 84 in which the fastening hole is formed and the fastening hole 64h provided in the bracket 64 is fastened with a nut 94n. A bolt 96b that passes through the fastening portion 86 in which the fastening hole is formed and the fastening hole 66h provided in the bracket 66 is fastened with a nut 96n. The heat insulation member 70 is fixed to the transfer 26 by a fastener 94 composed of the bolt 94b and the nut 94n and a fastener 96 composed of the bolt 96b and the nut 96n. In the direction of the axis C, both the fastening portions 84 and 86 are provided on one side of the tip portion 74 and the tip portion 76. The heat insulation member 70 has a structure in which it is attached to the transfer 26 in a cantilevered manner by fastening the fastening portions 84 and 86 respectively.
[0020] When the heat insulation member 70 is developed in a direction perpendicular to the plate thickness direction (see FIG. 4), the tip of the tip portion 74 extending in one longitudinal direction from the base portion 72 is the edge portion 70t1, and the tip of the tip portion 76 extending in the other longitudinal direction from the base portion 72 is the edge portion 70t2. One longitudinal direction and the other longitudinal direction are substantially perpendicular. When the heat insulation member 70 is developed in a direction perpendicular to the plate thickness direction, the edge portion on the side where the edge portion 70t1 and one end of the edge portion 70t2 are connected and attached in a cantilevered manner is the edge portion 70e1, and the edge portion on the free end side where the other end of the edge portion 70t1 and the other end of the edge portion 70t2 are connected is the edge portion 70e2. The edge portion 70e1 corresponds to the "edge portion on the side where it is attached in a cantilevered manner" in the present invention. When the heat insulation member 70 is developed in a direction perpendicular to the plate thickness direction, the heat insulation member 70 is surrounded by the edge portion 70t1, the edge portion 70t2, the edge portion 70e1, and the edge portion 70e2.
[0021] The heat-shielding member 70 is provided with a plurality of flat portions 70p and stepped portions 70s which are areas other than the plurality of flat portions 70p. The flat portions 70p are flat areas that are parallel or substantially parallel to the axis C. For example, the surface of the flat portions 70p is parallel to one longitudinal direction extending from the base portion 72 to the tip portion 74 or to another longitudinal direction extending from the base portion 72 to the tip portion 76. The stepped portions 70s are areas that connect adjacent flat portions 70p among the plurality of flat portions 70p. Specifically, the flat portions 70p are parts of the heat-shielding member 70 that are made of a plate-like body and have not been bent by press working, while the stepped portions 70s are parts that have been bent by press working. When stepped portions 70s are provided, the overall rigidity of the heat-shielding member 70 is increased compared to when stepped portions 70s are not provided.
[0022] A notch 78 is provided at the edge 70e1 of the heat-shielding member 70. As will be described later, the notch 78 suppresses localized stress concentration due to the bending load F [N] generated in the cross section S perpendicular to the straight line L connecting the two fastening parts 84 and 86, respectively. The specific shape of the notch 78 will be described later.
[0023] Figure 4 is a diagram illustrating the shape of the notch 78 provided in the heat shield member 70 shown in Figure 3 and the stress due to the bending load F, where (a) is a schematic diagram of the heat shield member 70 shown in Figure 3 when unfolded in a direction perpendicular to the plate thickness direction, and (b) is a diagram illustrating the stress due to the bending load F generated at the location where the notch 78 is provided.
[0024] As mentioned above, when the heat shield member 70 is unfolded in a direction perpendicular to the plate thickness direction, as shown in Figure 4(a), the heat shield member 70 has an L-shape with two tip portions 74 and 76 extending from the base portion 72 in directions substantially perpendicular to each other. Note that the actual heat shield member 70 is folded in the direction of arrow A along the fold line FL shown in Figure 4. In Figure 4, the area cut out by the notch 78 is indicated by a shaded line.
[0025] The notch 78 cuts out, for example, the boundary portion 70b (see Figure 3) between the flat portion 70p and the stepped portion 70s, that is, the base portion of the stepped portion 70s in the flat portion 70p. The boundary portion 70b corresponds to the "base portion" in the present invention. In this embodiment, the notch 78 extends in a direction perpendicular to the fold line FL and cuts out the heat shield member 70. When the heat shield member 70 is unfolded in a direction perpendicular to the plate thickness direction, stress due to bending load F occurs in the heat shield member 70 in a cross section S perpendicular to the straight line L connecting the fastening portions 84 and 86, respectively. The bending load F is caused by, for example, vibration of the engine 12.
[0026] As shown in Figure 4(b), the cross-section S perpendicular to the straight line L includes, for example, cross-sections S1 to S5. Cross-sections S1 to S5 are cross-sections S that pass through positions P1 to P5 at the edge of the notch 78, respectively. In cross-sections S1 to S4, the region adjacent to one side of these cross-sections S1 to S4 is connected to the fastening portion 84, and the region adjacent to the other side is connected to the fastening portion 86. Therefore, stress due to the bending load F is generated in each of these cross-sections S1 to S4. In cross-section S5, the region adjacent to one side of cross-section S5 is not connected to either the fastening portion 84 or the fastening portion 86, while the region adjacent to the other side is connected to both the fastening portion 84 and the fastening portion 86. Therefore, no stress due to the bending load F is generated in cross-section S5. Among the cross-sections S perpendicular to the straight line L, the cross-section S in which the region adjacent to one side is connected to the fastening portion 84 and the region adjacent to the other side is connected to the fastening portion 86 corresponds to the "location where stress due to bending load is generated" in the present invention.
[0027] At the edges of the notch 78 where stress due to the bending load F occurs, the edges of the notch 78 are not sharp corners where the cut-out portion is pointed. That is, the edges of the notch 78 are curves with a gently changing curvature or straight lines continuously connected to such curves. For example, the notch 78 may be a U-shape or a semicircle, including an arc. If we consider the curvature of a straight line to be infinite, the edges of the notch 78 have a gently changing curvature. For example, each position between P1 and P4 on the edge of the notch 78 is where stress due to the bending load F occurs, but the cut-out portion is not a sharp corner. Therefore, stress due to the bending load F does not concentrate locally at each position between P1 and P4. Furthermore, the provision of the notches 78 distributes the stress caused by the bending load F, while improving the flexibility of the heat shielding member 70, allowing it to flex around the respective cross-sections S perpendicular to the straight line L connecting the fastening portions 84 and 86.
[0028] For example, in the comparative example where notch 78 is not provided, the missing portion at position P1 is a sharp corner. At position P1, the curvature abruptly changes from a straight line with infinite curvature to zero. Therefore, in the comparative example, the stress due to the bending load F is locally concentrated at position P1, making it prone to crack formation in the direction indicated by the white arrow from position P1.
[0029] In this embodiment, a notch 78 is provided in one location, but for example, in the heat shielding member 70, notches 78 may also be provided at positions X1, X2, etc., as shown in Figure 4(a).
[0030] In this embodiment, the heat shield member 70 is used to protect the constant velocity joint 40 extending in the direction of the axis C, and is composed of a plate-like body and is L-shaped with two tip portions 74 and 76 when unfolded in a direction perpendicular to the thickness direction of the plate-like body. Furthermore, (a) one fastening portion 84 and one fastening portion 86 are provided at each of the two tip portions 74 and 76 of the heat shield member 70, (b) the heat shield member 70 is attached to the transfer 26 in a cantilevered manner by fastening the fastening portions 84 and 86 respectively, and (c) a notch 78 is provided at the edge end 70e1 of the heat shield member 70 to suppress localized stress concentration due to bending load F generated in a cross section S perpendicular to the straight line L connecting the fastening portions 84 and 86. In this way, in the heat shield member 70 which is attached in a cantilevered manner, the provision of the notch 78 suppresses localized stress concentration due to bending load F and suppresses damage (e.g., cracking) to the heat shield member 70.
[0031] In this embodiment, when the heat shielding member 70 is unfolded in a direction perpendicular to the plate thickness direction, the curvature at the edge of the notch 78 changes gradually at locations where stress due to the bending load F occurs in the heat shielding member 70. This shape of the notch 78 effectively suppresses localized stress concentration due to the bending load F.
[0032] According to this embodiment, (a) the heat shielding member 70 is provided with a plurality of flat portions 70p and stepped portions 70s that connect adjacent flat portions 70p, and (b) the notches 78 are provided in the flat portions 70p. The provision of the stepped portions 70s increases the overall rigidity of the heat shielding member 70, and the provision of the notches 78 in the flat portions 70p facilitates the manufacturing of the heat shielding member 70 by press working.
[0033] In this embodiment, the notch 78 cuts out the boundary portion 70b. The stepped portion 70s has higher rigidity than the flat portion 70p. Therefore, the heat shielding member 70 is prone to localized bending due to the bending load F at the boundary portion 70b where the rigidity changes abruptly, and stress due to the bending load F tends to concentrate locally at the boundary portion 70b. Because the notch 78 cuts out the boundary portion 70b, the area prone to bending due to the bending load F is more easily dispersed away from the boundary portion 70b. As a result, localized stress concentration due to the bending load F is suppressed, and damage to the heat shielding member 70 is more easily suppressed. [Examples]
[0034] Figure 5 is a schematic diagram of the heat-shielding member 170 according to Embodiment 2 of the present invention when it is unfolded in a direction perpendicular to the plate thickness direction. The heat-shielding member 170 is mounted on a vehicle 10 having the same configuration as the vehicle 10 in Embodiment 1 described above. The heat-shielding member 170 has substantially the same configuration as the heat-shielding member 70 according to Embodiment 1 described above, but differs in that it has a notch 178 instead of a notch 78. Therefore, in this embodiment, the explanation will focus on the parts that differ from Embodiment 1, and parts that are substantially common in function with Embodiment 1 will be given the same reference numerals and their explanations will be omitted as appropriate. The heat-shielding member 170 corresponds to the "protective cover" in the present invention.
[0035] The shape of notch 178 is almost the same as that of notch 78, but the shape differs in the areas where no stress is generated due to the bending load F. That is, the shape of each position between positions P1 and P4 on the edge of notch 178 is the same as that of notch 78, but the shape of each position between positions P4 and P6 on the edge of notch 178 is different from that of notch 78. For example, each position between P4 and P7 is an area where no stress is generated due to the bending load F. Therefore, it is not necessarily required to gradually change the curvature of the edge of notch 178 at these positions. For example, notch 178 can be U-shaped.
[0036] According to this embodiment, by having the same configuration as in the aforementioned Embodiment 1, the same effects as in Embodiment 1 are achieved based on that configuration. [Examples]
[0037] Figure 6 is a schematic diagram of the heat-shielding member 270 according to Embodiment 3 of the present invention when it is unfolded in a direction perpendicular to the plate thickness direction. The heat-shielding member 270 is mounted on a vehicle 10 having the same configuration as the vehicle 10 in Embodiment 1 described above. The heat-shielding member 270 has substantially the same configuration as the heat-shielding member 70 according to Embodiment 1 described above, but differs in that it has a notch 278 instead of a notch 78. Therefore, in this embodiment, the explanation will focus on the parts that differ from Embodiment 1, and parts that are substantially common in function with Embodiment 1 will be given the same reference numerals and their explanations will be omitted as appropriate. The heat-shielding member 270 corresponds to the "protective cover" in the present invention.
[0038] Section S8 is a section S that passes through position P8 at the edge of the notch 278. Section S9 is a section S that passes through position P9 at the edge of the notch 278. The shape of the notch 278 is substantially the same as that of the notch 78, but differs in that the notch 278 extends in a direction parallel to the fold line FL and cuts out the heat shield member 270. At the edge of the notch 278, stress due to the bending load F occurs at each position between P8 and P9. Therefore, the curvature at the edge of the notch 278 between positions P8 and P9 changes gradually.
[0039] According to this embodiment, by having the same configuration as in the aforementioned Embodiment 1, the same effects as in Embodiment 1 are achieved based on that configuration. [Examples]
[0040] Figure 7 is a schematic diagram of the heat-shielding member 370 according to Embodiment 4 of the present invention when it is unfolded in a direction perpendicular to the plate thickness direction. The heat-shielding member 370 is mounted on a vehicle 10 having the same configuration as the vehicle 10 in Embodiment 1 described above. The heat-shielding member 370 has substantially the same configuration as the heat-shielding member 70 according to Embodiment 1 described above, but differs in that it has a notch 378 instead of a notch 78. Therefore, in this embodiment, the explanation will focus on the parts that differ from Embodiment 1, and parts that are substantially common in function with Embodiment 1 will be given the same reference numerals and their explanations will be omitted as appropriate. The heat-shielding member 370 corresponds to the "protective cover" in the present invention.
[0041] Section S10 is a section S that passes through position P10 at the edge of the notch 378. Section S11 is a section S that passes through position P11 at the edge of the notch 378. The shape of the notch 378 is almost the same as that of the notch 78, but it differs in that the notch 378 extends in a direction perpendicular to the straight line L (for example, the direction in which sections S10 and S11 extend) and cuts out the heat shield member 370, rather than in a direction parallel to or perpendicular to the fold line FL. At the edge of the notch 378, the locations where stress due to the bending load F occurs are at each position between P10 and P11. Therefore, the curvature at the edge of the notch 378 between positions P10 and P11 changes gradually.
[0042] According to this embodiment, by having the same configuration as in the aforementioned Embodiment 1, the same effects as in Embodiment 1 are achieved based on that configuration.
[0043] The above-described examples are embodiments of the present invention, and the present invention can be implemented in various modified and improved forms based on the knowledge of those skilled in the art, without departing from its spirit.
[0044] In the aforementioned embodiments 1 to 4, the notches 78, 178, 278, and 378 all cut out the boundary portion 70b, but the present invention is not limited to this embodiment. For example, the notches 78, 178, 278, and 378 may cut out only the flat portion 70p. Even in such an embodiment, compared to the case where the notches 78, 178, 278, and 378 are not provided, localized stress concentration due to bending load F in the heat shield member 70 is suppressed, and damage to the heat shield members 70, 170, 270, and 370 is suppressed.
[0045] In the aforementioned embodiments 1 to 4, the heat shielding members 70, 170, 270, and 370 were provided with one notch each (78, 178, 278, and 378), but the invention is not limited to this configuration, and multiple notches each may be provided.
[0046] In the aforementioned embodiments 1 to 4, each of the two end portions 74 and 76 was provided with one fastening portion, but the present invention is not limited to this embodiment. For example, there may be multiple fastening portions provided on the two end portions 74 and 76. In such an embodiment, stress due to the bending load F occurs in the cross section S perpendicular to the straight line connecting either of the fastening portions provided on end portion 74 and either of the fastening portions provided on end portion 76. By providing the notches 78, 178, 278, and 378, localized concentration of stress due to the bending load F in the heat shield members 70, 170, 270, and 370 is suppressed.
[0047] In the aforementioned embodiments 1 to 4, the heat-shielding members 70, 170, 270, and 370 were folded along a single fold line FL parallel or substantially parallel to the axis C, but the present invention is not limited to this embodiment. For example, the heat-shielding members 70, 170, 270, and 370 may be folded along multiple fold lines parallel or substantially parallel to the axis C.
[0048] In the aforementioned embodiments 1 to 4, the "protective cover" in the present invention was a heat insulator consisting of heat shielding members 70, 170, 270, and 370, but the present invention is not limited to this embodiment. For example, the present invention can also be applied to covers used to protect against collisions with constant velocity couplings caused by rocks or other objects on the road surface.
[0049] In the aforementioned embodiments 1 to 4, the vehicle 10 on which the heat shielding members 70, 170, 270, and 370 were installed was a four-wheel drive vehicle based on the FR system. However, it is not limited to this, and may also be a two-wheel drive vehicle with the FR system. Furthermore, the present invention is also applicable to vehicles in which the power source for driving is an electric motor rather than an engine 12. [Explanation of Symbols]
[0050] 40: Constant velocity joint (rotating member), 70, 170, 270, 370: Heat shield member (protective cover), 70b: Boundary section (root section), 70e1: Edge section (edge section on the side that is cantilevered), 70p: Flat section, 70s: Step section, 74, 76: Tip section, 78, 178, 278, 378: Notch, 84, 86: Fastening section, C: Axis, F: Bending load, L: Straight line (straight line connecting each fastening section), S: Cross section (cross section perpendicular to the straight line connecting each fastening section)
Claims
1. A protective cover used to protect a rotating member extending in the axial direction, which is made of a plate-like body and has an L-shaped shape having two tip portions when unfolded in a direction perpendicular to the thickness direction of the plate-like body, Each of the two aforementioned tip portions is provided with a fastening portion. The protective cover is attached in a cantilevered manner when the fastening parts are fastened together. The edge end of the protective cover that is attached in a cantilevered manner is provided with a notch to suppress localized stress concentration due to bending loads occurring in a cross section perpendicular to the straight line connecting the fastening portions. A protective cover characterized by the following features.
2. When the protective cover is unfolded in a direction perpendicular to the thickness direction of the plate, the curvature at the edge of the notch changes gradually at the location where stress due to the bending load occurs. The protective cover according to feature 1.
3. The protective cover is provided with a plurality of flat sections and stepped sections that connect adjacent flat sections. The aforementioned notch is provided in the flat portion. The protective cover according to feature 1.
4. The protective cover is provided with a plurality of flat sections and stepped sections that connect adjacent flat sections. The aforementioned notch is a cutout at the base of the stepped portion in the flat portion. The protective cover according to feature 1.
5. The protective cover is attached in the cantilevered manner by fastening parts, one of which is provided at each of the two ends. A protective cover according to any one of features 1 to 4.