Vent cover

Abstract

[Problem] To promote discharge of liquid from a vent filter and prevent deterioration of the sealing properties of the vent filter. [Solution] A vent cover is provided to a side part of a casing and covers a vent part of a passage for circulating a fluid between the interior and the exterior of the casing. A cover opening part to which a vent filter having a waterproof moisture-permeable function is attached is formed in the vent cover. A rib is provided around the cover opening part so as to protrude toward the exterior of the casing from the edge of the cover opening part, and such that a gap is formed on the vertically lower side in the casing. The rib has: a rib body section surrounding the periphery of the cover opening part, and one end section and the other end section of the rib body section, said end sections facing each other with the gap therebetween. The one end section is arranged at a position closer to a virtual line passing through the cover opening part in the vertical direction than the other end section.

Description

Vent cover

[0001] The present invention relates to a vent cover.

[0002] The drive transmission device disclosed in Patent Document 1 has a casing containing a transmission gear, and a breathing passage for ventilation between the inside and outside of the casing. The casing has an opening (vent) for the breathing passage, and the vent is covered with a vent cover. A waterproof and breathable vent filter is attached to the vent, which prevents the inflow of fluid from the outside and allows the passage of gas from the inside.

[0003] Japanese Patent Application Laid-Open No. 2021-151100

[0004] In the drive transmission device disclosed in Patent Document 1, liquid such as water may accumulate around the vent filter. When liquid accumulates in the vent filter, substances precipitated from the accumulated liquid may deteriorate the vent cover, potentially reducing the sealing performance of the vent filter.

[0005] Therefore, an object of the present invention is to promote the discharge of liquid from a vent filter and prevent a decrease in the sealing performance of the vent filter.

[0006] According to one aspect of the present invention, there is provided a vent cover that is provided on the side of a casing and covers a vent portion of a passage that allows fluid to circulate between the inside and outside of the casing, wherein the vent cover has a cover opening formed therein to which a vent filter with waterproof and breathable properties is attached, and a rib is provided around the cover opening that protrudes toward the outside of the casing beyond the edge of the cover opening and has a gap formed vertically below the casing, the rib having a rib main body portion that surrounds the periphery of the cover opening and one end and the other end of the rib main body portion that face each other across the gap, and the one end is positioned closer to an imaginary line that passes through the cover opening in the vertical direction than the other end.

[0007] According to one aspect of the present invention, the discharge of liquid from the vent filter is promoted, deterioration of the vent cover due to substances precipitated from the liquid can be suppressed, and a decrease in the sealing ability of the vent filter can be prevented.

[0008] Fig. 1 is an external side view illustrating the external appearance of a drive transmission device to which a vent cover according to an embodiment of the present invention is applied. Fig. 2 is an enlarged view of a main part of the vent cover. Fig. 3 is a cross-sectional view taken along line III-III in Fig. 2.

[0009] Hereinafter, a vent cover 100 according to an embodiment of the present invention will be described with reference to the drawings.

[0010] FIG. 1 is an external side view illustrating the external appearance of a drive transmission device 1 to which a vent cover 100 is applied.

[0011] (Drive Transmission Device) The drive transmission device 1 shown in FIG. 1 is, as an example, a transmission device for transmitting power of a motor to drive wheels provided in an electric vehicle.

[0012] The drive transmission device 1 includes a casing 10. Although not shown in Fig. 1, the casing 10 includes an input shaft to which power is input from the motor, an output shaft that outputs power to the drive wheels, and a plurality of transmission gears that connect the input shaft and the output shaft to transmit the power.

[0013] Oil for lubricating and cooling the input shaft, output shaft, and transmission gear is sealed inside the casing 10. The oil circulates inside the casing 10 as the input shaft, output shaft, and transmission gear rotate.

[0014] The drive transmission device 1 is provided with a breather that functions to release air present inside the casing 10 and pressure inside the casing 10. The breather is formed with a passage 11 for ventilation between the inside and outside of the casing 10, and in this embodiment, an opening (vent portion) 12 of the passage is located on a side portion 10S of the casing 10 (see FIG. 3).

[0015] As shown in Fig. 1, the casing 10 has a vent cover mounting portion 13 formed around a vent portion 12 disposed on a side portion 10S of the casing 10. A vent cover 100 (described later) is mounted to the vent cover mounting portion 13. Note that the upper and lower directions U and D in the vertical direction shown in Fig. 1 indicate the up and down directions when the device is mounted on a vehicle.

[0016] (Vent Cover) Fig. 2 is an enlarged view showing the vent cover 100. Fig. 3 is a cross-sectional view taken along line III-III in Fig. 2.

[0017] The vent cover 100 is a cover that covers the vent portion 12 of the passage 11 arranged in the casing 10.

[0018] As shown in Fig. 2, the vent cover 100 is formed with a cover opening 101. In Fig. 2, the vent filter 130 is not shown in order to explain the vent cover 100.

[0019] The cover opening 101 is configured so that a vent filter 130 can be attached thereto (see FIG. 3).

[0020] 2, the vent cover 100 has a rib 110 around the cover opening 101. The rib 110 protrudes outward from the casing 10 beyond the edge 102 of the cover opening 101. A gap 111 is formed below the rib 110 in the vertical direction D of the casing 10.

[0021] The rib 110 has a substantially annular rib main body 120 that surrounds the periphery of the cover opening 101, and one end 112 and the other end 113 of the rib main body 120 that face each other across a gap 111. The one end 112 of the rib 110 is located closer to the lower end of the cover opening 101, in other words, closer to an imaginary line L that passes vertically through the center of the cover opening 101, than the other end 113.

[0022] In this embodiment, one end 112 extends beyond the imaginary line L toward the other end 113. In other words, the gap 111 does not exist on the imaginary line L that passes through the cover opening 101 in the vertical direction (the rib 110 exists on the imaginary line, but the gap 111 does not exist).

[0023] Furthermore, when the vent filter 130 is attached, one end 112 extends beyond an imaginary line L that passes through the bottom end of the vent filter 130 in the vertical direction to the other end 113 side.

[0024] In this embodiment, one end 112 has a bent portion 114 bent downward in the vertical direction D. The bent portion 114 is bent downward in the vertical direction D, in a direction away from the other end 113, i.e., in the direction of arrow A in Fig. 2. In other words, the bent portion 114 is bent downward in the vertical direction (vertical direction D) from the rib main body 120 of the rib 110, which is formed in a substantially annular shape.

[0025] In the vertical direction D, a position P1 of one end 112 of the rib 110 is lower than a position P2 of the other end 113.

[0026] The passage 11 shown in FIG. 3 has a so-called labyrinth structure that allows gas G to circulate between the inside and outside of the casing 10 while preventing dust and water from the outside of the casing 10 from passing through the passage and entering the inside of the casing 10.

[0027] As shown in Figure 3, the cover opening 101 connects the space S formed by the vent cover mounting portion 13 formed on the casing 10 and the vent cover 100 attached to the vent cover mounting portion 13 to the outside of the vent cover 100.

[0028] The vent filter 130 is provided with a filter 131 having waterproof and moisture-permeable properties that prevents the inflow of fluid from outside the vent cover 100 and allows the passage of gas G from the inside and outside (see the solid arrows in FIG. 3). An O-ring 132 is fitted between the cover opening 101 and the vent filter 130, and the passage between the vent filter 130 and the cover opening 101 is sealed except for the filter 131.

[0029] As shown in FIG. 3 , the height H of the rib 110 from the surface 100S of the vent cover 100 is higher than the top 130A of the vent filter 130 when the vent filter 130 is attached to the cover opening 101.

[0030] Also, as shown in Figure 3, in the vent cover 100, a recess 115 is formed in the gap 111 between one end 112 and the other end 113 of the rib 110, which is recessed toward the inside of the casing 10 further than the standing base point 112B of the one end 112.

[0031] Below the recess 115 in the vertical direction D, an inclined groove 116 is formed so as to facilitate the discharge of the liquid Lq from the recess 115 .

[0032] (Operations and Effects) The configuration and operations and effects of the present embodiment will be described below.

[0033] (1) The vent cover 100 is a vent cover that is provided on the side 10S of the casing 10 and covers the vent portion 12 of the passage 11 that allows fluid to circulate between the inside and outside of the casing 10. The vent cover 100 has a cover opening 101 formed therein to which a vent filter 130 having waterproof and breathable properties is attached. The vent cover 100 has a rib 110 that protrudes toward the outside of the casing 10 beyond the edge 102 of the cover opening 101 and has a gap 111 formed on the vertical lower side U of the casing 10. The rib 110 has a rib main body portion 120 that surrounds the periphery of the cover opening 101 and one end 112 and the other end 113 of the rib main body portion 120 that face each other via the gap 111. The one end 112 is positioned closer to an imaginary line that passes vertically through the cover opening 101 than the other end 113.

[0034] Rainwater splashed up from tires or the like may splash onto the casing 10, and liquid such as water may adhere to the periphery of the vent filter.

[0035] In contrast, in the configuration (1), one end 112 is positioned closer to the imaginary line that passes vertically through the cover opening 101 than the other end 113. Therefore, the liquid around the vent filter 130 is more likely to flow along the rib 110 and be guided to the tip of one end 112.

[0036] This also makes it easier for the liquid Lq adhering to the periphery of the vent filter 130 to be guided into the gap 111 between one end 112 and the other end of the rib 110 .

[0037] Therefore, the vent cover 100 can promote the discharge of the liquid Lq from the vent filter 130 from the inside to the outside of the ribs 110, and can prevent a decrease in the sealing performance of the vent filter 130 due to the liquid Lq.

[0038] (2) In the rib 110, one end 112 extends toward the other end 113 side beyond the imaginary line L.

[0039] This configuration makes it easier for liquid that flows down the rib main body 120 of the rib 110 in the vertical direction to be received by the one end 112. The liquid received by the one end 112 further aggregates the surrounding liquid due to surface tension, and when it grows to a predetermined size, it drips under its own weight. This further promotes the discharge of liquid from the vent filter 130 to the outside of the rib 110.

[0040] (3) One end 112 has a bent portion 114 that is bent downward in the vertical direction and away from the other end 113 .

[0041] According to this configuration, the liquid Lq that has been guided into the gap 111 by the bent portion 114 flows along the bent portion 114 at one end 112 , and is easily discharged from the gap 111 .

[0042] (4) The position P1 of the one end 112 is located lower than the position P2 of the other end 113 in the vertical direction of the casing 10 .

[0043] Due to surface tension, the liquid Lq introduced into the gap 111 tends to remain between the one end 112 and the other end 113. In contrast, with this configuration, the position P1 of the one end 112 is lower than the position P2 of the other end 113, so the liquid Lq introduced into the gap 111 flows toward the one end 112 and is more likely to be discharged from the gap 111.

[0044] (5) The height H of the rib 110 from the surface 100S of the vent cover 100 is higher than the top 130A of the vent filter 130 when the vent filter 130 is attached to the cover opening 101.

[0045] According to this configuration, the rib 110 protrudes beyond the vent filter 130, so that the vent filter 130 can be protected.

[0046] (6) In the gap 111 between one end 112 and the other end 113, a recess 115 is formed that is recessed toward the inside of the casing 10 further than the rising base point 112B of at least one end 112 of the rib 110.

[0047] With this configuration, liquid that has flowed into gap 111 tends to remain in recess 115. Furthermore, the liquid that remains in recess 115 further aggregates the surrounding liquid due to surface tension, and when it grows to a predetermined size, it drips due to the weight of the liquid that has accumulated in recess 115. By storing liquid in recess 115, it is possible to enhance the effect of collecting liquid from around vent filter 130 and the effect of promoting the discharge of liquid.

[0048] [Other Embodiments] The present embodiment has been described above, but the above embodiment merely shows one application example of the present invention, and is not intended to limit the technical scope of the present invention to the specific configuration of the above embodiment.

[0049] Although the vent cover 100 according to this embodiment has been described as being applied to the passage 11 disposed in the breather of the drive transmission device 1, the application of the vent cover 100 is not limited to the drive transmission device 1. For example, the vent cover 100 can be applied to any device that is equipped with a ventilation mechanism for adjusting the pressure inside the casing.

[0050] In the present embodiment, the rib 110 has a substantially annular shape surrounding the cover opening 101, but the shape of the rib 110 is not limited to the illustrated shape. For example, the cover opening and the rib may have a rectangular shape.

[0051] In addition, in this embodiment, the rib main body portion 120 of the rib 110 is formed in a continuous ridge shape from one end 112 to the other end 113, but the rib main body portion 120 of the rib 110 may also have a structure having a divided portion, as long as it does not interfere with the fluid discharge effect on the lower side in the vertical direction D.

[0052] The shape of the vent filter 130 shown in this embodiment is merely an example, and any shape that has waterproof and moisture-permeable properties in the environment in which the drive transmission device 1 is used can be used.

[0053] DESCRIPTION OF SYMBOLS 1 Drive transmission device 10 Casing 10S Side of casing 11 Passage 12 Passage opening (vent portion) 13 Vent cover mounting portion 100 Vent cover 100S Surface of vent cover 101 Cover opening 102 Edge of cover opening 110 Rib 111 Gap 112, 113 End 114 Bent portion 115 Recess 116 Groove 120 Rib main body 130 Vent filter 130A Top

Claims

1. A vent cover provided on the side of a casing to cover a vent portion of a passage that allows fluid to circulate between the inside and outside of the casing, wherein the vent cover has a cover opening formed therein to which a vent filter with waterproof and breathable functions is attached, and a rib is provided around the cover opening, protruding beyond the edge of the cover opening toward the outside of the casing and having a gap formed on the vertically lower side of the casing, the rib having a rib main body portion that surrounds the periphery of the cover opening, and one end and the other end of the rib main body portion facing each other across the gap, the one end being positioned closer to an imaginary line that passes through the cover opening in the vertical direction than the other end.

2. A vent cover according to claim 1, wherein the one end portion extends toward the other end portion beyond the imaginary line.

3. A vent cover according to claim 1 or 2, wherein the one end has a bent portion that is bent downward in the vertical direction and away from the other end.

4. A vent cover according to claim 1, wherein the one end is positioned lower than the other end in the vertical direction of the casing.

5. A vent cover according to claim 1, wherein the height of the rib from the surface of the vent cover is higher than the top of the vent filter when the vent filter is attached to the cover opening.

6. A vent cover as claimed in claim 1, wherein a recess is formed in the gap between the one end and the other end of the rib, recessed towards the inside of the casing further than the rising base point of at least the one end of the rib.

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