JP2013061007A - Breather device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a breather device capable of improving the effect of preventing the intrusion of water drops or the like while reducing the number of part items.SOLUTION: The breather device includes: a cylindrical member 2 which forms a breather space 2a communicating with the internal space of a case; a valve member 3; and a cover member 4 which covers the valve member 3. The valve member 3 has a seal 31 disposed over the whole circumference of an upper end, and a slit forming portion 32 which is extended upward from the seal 31 above the breather space 2a so that one direction in a plan view corresponds to the longitudinal direction to close an upper end opening of the cylindrical member 2 together with the seal 31 and has a slit 32a extended along the longitudinal direction with the upper end facing a cover space 4a and the lower end facing the breather space 2a above the upper end opening. The valve member 3 or the cover member 4 has a space forming portion 33 which forms a part of the cover space 4a above the slit 32a.

Description

  The present invention relates to a breather device used for a case of a transmission.

  The breather device is provided in a transmission mounted on the vehicle. The breather device has a so-called check valve function, and discharges air inside the case to the outside when the pressure inside the case of the transmission rises. In the breather device, the opening (breathing hole) is closed with a valve so that water drops or the like do not enter the case through the breather device, and the opening / closing portion of the valve is covered with a cover member. Such a breather device is described in, for example, Japanese Patent Application Laid-Open No. 2005-082125 (Patent Document 1) and Japanese Patent Application Laid-Open No. 6-117521 (Patent Document 2).

  For example, a conventional breather device includes a cylindrical member that opens up and down, and a lid member (valve) that is supported by a spring and a support member on the inner surface of the upper wall of the cover member. The lid member is urged from above by a spring so as to close the upper end opening of the cylindrical member, and is pressed against the upper end of the cylindrical member. When the pressure inside the case rises, the lid member is pushed up against the biasing force of the spring by the internal pressure, and the inside of the case communicates with the outside.

Japanese Patent Laying-Open No. 2005-082125 JP-A-6-117521

  However, the breather device as described above has to install a spring, a lid member, and the like inside the cover, and has a large number of parts and complicated manufacturing operations. Further, the breather device has a problem in terms of preventing water droplets or the like from entering because the position where the inside of the case communicates with the outside is the upper end opening position of the cylindrical member.

  This invention is completed in view of the said subject, and makes it the subject which should be solved to provide the breather apparatus which can reduce a number of parts and can improve the approach prevention action, such as a water drop.

The transmission according to claim 1, which solves the above problem, is a breather device that discharges air inside the case to the outside in response to an increase in internal pressure of the case in which the transmission mechanism of the transmission is accommodated. ,
A cylindrical member that opens up and down and forms a breather space that communicates with the internal space of the case below;
A valve member made of an elastic material provided at an upper end portion of the cylindrical member so as to close an upper end opening of the cylindrical member;
A cover member that covers the valve member, forms a cover space between the valve member, and forms a gap for communicating the cover space with the outside;
With
The valve member is
A seal portion disposed at the upper end of the cylindrical member;
Extending upward from the seal portion above the breather space so that one direction in a plan view is the longitudinal direction, closes the upper end opening of the cylindrical member together with the seal portion, extends along the longitudinal direction, and the upper end is the A slit forming portion provided with a slit facing the cover space and having a lower end above the upper end opening and facing the breather space;
Have
The valve member or the cover member has a space forming part that forms a part of the cover space above the slit,
The slit is opened in response to an increase in internal pressure of the case, and communicates the breather space and the cover space.

  Here, “plan view” in this specification means that the lower side is viewed from above, and what is visible corresponds to a plan view of the object (such as FIG. 4).

  According to the first aspect of the present invention, the valve member having a slit that opens as the internal pressure of the case increases serves as a check valve. In other words, according to the present invention, since the check valve function can be exhibited by one valve member, there is no need to attach a plurality of members such as a lid member, a spring member, and a spring support member in the cover member as in the prior art. . As a result, the number of parts can be reduced and the manufacturing operation can be simplified. In addition, according to the present invention, the slit that communicates the breather space and the cover space is located above the upper end opening of the cylindrical member, so that water droplets or the like are less likely to enter. Thus, according to the present invention, the number of parts can be reduced, and the action of preventing the entry of water droplets and the like can be improved.

It is a fragmentary sectional view showing the breather device of this embodiment. It is the sectional view on the AA line in FIG. 1 which shows the breather apparatus of this embodiment. It is a perspective view which shows the valve member of this embodiment. It is a top view which shows the valve member of this embodiment. It is the sectional view on the AA line in FIG. 1 which shows the deformation | transformation aspect of the breather apparatus of this embodiment.

  The breather apparatus of the present invention will be described in detail below based on a typical embodiment. The breather device is a device that communicates the internal space of a case (not shown) in which a transmission mechanism of a transmission (not shown) is accommodated with the outside in accordance with an increase in the internal pressure of the case. The breather device also prevents water drops and the like from entering the case. Each figure used for explanation is a conceptual diagram, and the shape of each part may not necessarily be exact.

  As shown in FIGS. 1 and 2, the breather device 1 of the present embodiment includes a cylindrical member 2, a valve member 3, and a cover member 4. The cylindrical member 2 is a substantially cylindrical metal member opened up and down, and has a breather space 2a whose lower part communicates with the internal space of the case. In other words, the cylindrical member 2 forms a breather space 2a that allows communication between the outside (the outside through a cover space 4a described later) and the internal space of the case. The cylindrical member 2 defines the breather space 2a.

  The valve member 3 is provided at an upper end portion 21 (an upper portion forming the upper end opening) of the cylindrical member 2 so as to close the upper end opening of the cylindrical member 2. The valve member 3 is integrally formed of a rubber material. The valve member 3 is press-fitted into the upper end portion 21 of the cylindrical member 2. More specifically, the valve member 3 includes a seal part 31, a slit forming part 32, and a space forming part 33.

  The seal portion 31 is disposed on the entire upper end portion 21 of the cylindrical member 2. Specifically, the seal portion 31 is formed in an annular shape, and includes an annular base portion 311 and a protruding portion 312 that protrudes downward from the entire inner peripheral edge of the base portion 311. The base portion 311 is in contact with the entire circumference of the upper end surface of the upper end portion 21 of the cylindrical member 2. The protruding portion 312 is in contact with the entire inner peripheral surface of the upper end portion 21 of the cylindrical member 2. The outer diameter of the protruding portion 312 is formed larger than the inner diameter of the upper end portion 21 of the cylindrical member 2 (the diameter of the upper end opening). The seal portion 31 is press-fitted and fixed to the upper end portion 21 of the cylindrical member 2, and is in close contact with the upper end portion 21 so as to seal the opening edge.

  The slit forming portion 32 extends upward from the seal portion 31 above the breather space 2a so that one direction in a plan view (see FIG. 4) is the longitudinal direction. In other words, “one direction in plan view” can be said to be one direction orthogonal to the axial direction (vertical direction) of the cylindrical member 2. In the present embodiment, as shown in FIGS. 3 and 4, the slit forming portion 32 has a substantially rectangular parallelepiped shape, and continuously extends upward from the upper inner peripheral side of the seal portion 31. The upper end opening of the cylindrical member 2 is closed by a slit forming part 32 and a seal part 31.

  The slit forming part 32 has a slit 32a extending (cut) along the longitudinal direction at the center. That is, in the center of the slit forming part 32, there is a notch connected from the upper end to the lower end. In other words, the slit 32 a extends continuously from the upper end to the lower end of the slit forming portion 32. More specifically, the upper end of the slit 32a faces a cover space 4a described later, and the lower end of the slit 32a faces the breather space 2a above the upper end opening of the cylindrical member 2. When the slit 32a is opened, the breather space 2a and the cover space 4a communicate with each other through the slit 32a.

  The space forming portion 33 is composed of two protruding portions, and protrudes upward from both longitudinal side surfaces of the slit forming portion 32 and the upper portion of the seal portion 31. The space forming portion 33 has a substantially rectangular parallelepiped shape in which one side surface in the longitudinal direction has a convex arc shape. The upper end surface of the space forming portion 33 is located above the upper end surface of the slit forming portion 32.

  The space forming part 33 is located on both ends in the longitudinal direction of the slit 32a so as to sandwich the slit 32a in the longitudinal direction. The space forming portion 33 is in contact with the inner surface of the upper wall of the cover member 4 described later and supports the cover member 4. The space forming portion 33 is in contact with the cover member 4, thereby forming a part of a cover space 4a described later above the slit 32a. That is, the space forming portion 33 prevents the cover member 4 from coming into contact with the upper end surface of the slit forming portion 32 including the slit 32a. The space forming portion 33 may be formed in at least one of the seal portion 31 and the slit forming portion 32.

  The cover member 4 is a bottomed cylindrical member and covers the upper end portion 21 of the cylindrical member 2 and the valve member 3. In the present embodiment, the cover member 4 is formed in a bottomed cylindrical shape in accordance with the shape of the cylindrical member 2. The cover member 4 is disposed on the outer peripheral side of the upper end portion 21 of the cylindrical member 2 so as to cover the upper end portion 21 of the cylindrical member 2 and the valve member 3. However, the cover member 4 should just be arrange | positioned so that the upper end opening of the valve member 3 may be covered.

  The cover member 4 has an internal space (cover space) 4a. The cover space 4 a is partitioned by the cover member 4 and the valve member 3. The cover space 4a extends mainly above the slit 32a and on both sides of the slit forming portion 32 and the space forming portion 33 in the short direction (direction orthogonal to the longitudinal direction in plan view). In other words, the cover space 4 a is formed above the slit 32 a and above the seal portion 31.

  Further, the cover member 4 forms a gap 4 b between the cover member 4 a and the outside between the outer peripheral surface of the upper end portion 21 of the cylindrical member 2. That is, a gap 4 d is formed between the inner peripheral surface of the cover member 4 and the outer peripheral surface of the upper end portion 21. A part of the lower end portion of the cover member 4 is bent inward, and engages with a portion of the upper end portion 21 of the cylindrical member 2 that protrudes outward in the radial direction in the vertical direction. The valve member 3 can be manufactured, for example, by forming a cut (slit 32a) after being integrally formed.

  According to the breather device 1 of the present embodiment, when the internal pressure of the transmission case increases, the pressure of the breather space 2a leading to the internal space of the case also increases and opens the slit 32a. When the slit 32a is opened, the breather space 2a and the cover space 4a communicate with each other, and the air inside the case is discharged to the cover space 4a through the breather space 4a and the slit 32a. The cover space 4a communicates with the outside through the gap 4b and can be regarded as the same as the outside. That is, the air inside the case is released to the outside.

  On the other hand, during normal times (when the internal pressure of the case is not increased), the slit 32a is in a closed state. Then, atmospheric pressure (pressure in the cover space 4a) is applied to the side surface of the slit forming portion 32 from both sides in the short direction. Therefore, the opening of the slit 32a is a force in which the force in the opening direction due to the internal pressure of the case maintains the closed state of the slit forming portion 32 (the elastic force of the slit forming portion 32 and the large force applied to the side surface of the slit forming portion 32 Occurs when the pressure is overcome. The upper limit value of the internal pressure of the case for opening can be adjusted by the longitudinal and vertical lengths of the slit 32a, the shape (thickness, etc.) of the slit forming portion 32, the material of the valve member 3, and the like.

  According to the breather device 1 of the present embodiment, it is not necessary to attach a check valve composed of a plurality of parts inside the cover member 4, and it is only necessary to attach the valve member 3 to the tubular member 2. That is, according to the breather apparatus 1, the number of parts can be reduced, and the manufacturing operation and the manufacturing process can be simplified.

  Further, according to the breather device 1, the upper end opening of the cylindrical member 2 is sealed by the seal portion 31 of the valve member 3, and the opening position of the communication path connected to the breather space 2a (the upper end of the slit 32a) is the cylindrical member. 2 is located above the upper end opening. Conventionally, since the upper end opening of the cylindrical member 2 is closed by a lid member biased downward, the opening position is the same height as the upper end opening position of the cylindrical member 2. According to the breather apparatus 1 of this embodiment, since the opening position is high, entry of water droplets or the like is further prevented. As described above, according to the breather device 1, it is possible to improve the action of preventing the entry of water droplets and the like.

  Moreover, in the breather apparatus 1 of this embodiment, the space formation part 33 is formed in the position which pinches | interposes the slit 32a. Thereby, even when a water droplet or the like jumps against gravity, the space forming portion 33 serves as a barrier against entry from the longitudinal direction, and the entry of water droplets or the like is prevented. That is, the space forming portion 33 secures a space above the slit 32a and also exhibits a barrier function against water droplet intrusion from the longitudinal direction.

  Even if water droplets or the like are scattered on the slit 32a, the slit 32a is normally closed so that the entry of water droplets or the like is prevented. Further, since the opening of the slit 32a is instantaneous, entry into the inside from the slit 32a can be substantially prevented.

  As described above, according to the breather device 1 of the present embodiment, the number of parts can be reduced, the manufacturing operation can be simplified, and the action of preventing the entry of water droplets and the like can be improved.

  In addition, the breather apparatus of this invention is not restricted to the said embodiment. For example, the valve member 3 (seal portion 31) may be bonded to the upper end portion 21 of the tubular member 2 regardless of whether or not press fitting is performed. Moreover, the seal part 31 should just be the structure arrange | positioned in at least 1 of the outer peripheral surface whole periphery in the upper end part 21 of the cylinder member 2, an upper end surface whole periphery, and an inner peripheral surface whole periphery. That is, the seal part 31 should just be arrange | positioned at the upper end part 31 so that an upper end opening may be sealed with respect to the exterior. Moreover, you may form the cylinder member 2 and the valve member 3 integrally.

  Moreover, the space formation part 33 should just be able to ensure space (cover space 4a) above the slit 32a, for example, may be comprised by one protrusion part or three or more protrusion parts. Further, the shape of the space forming portion 33 is not limited.

  In addition, when a part of the inner surface of the cover member 4 protrudes, and a part of the protrusion contacts the valve member 3 to form a space on the slit 32a, the protruding part that is a part of the cover member 4 is a space. It becomes the formation part 33. For example, a configuration may be employed in which irregularities are provided on the inner surface of the cover member 4 and the convex portions and a part of the valve member 3 are brought into contact with each other. In this case, the space forming portion 33 is a convex portion formed on the cover member 4. That is, the space forming portion may be formed on one of the valve member 3 and the cover member 4.

  Moreover, the slit formation part 32 may provide the flange part 321 which protruded in the transversal direction on the side surface of a transversal direction, as shown in FIG. Thereby, the approach from the transversal direction lower direction, such as a water drop, can further be prevented. For example, entry can be more effectively prevented by providing the flange portion 321 over the entire upper edge portion of the side surface. Moreover, the cylinder member 2 should just have the breather space opened up and down, and may be cylindrical shape or a rectangular tube shape. The valve member 3 is not limited to a rubber material, and may be formed of a material (elastic material) that can be elastically deformed by an increase in internal pressure.

1: breather device,
2: cylindrical member, 2a: breather space, 21: upper end,
3: valve member, 31: seal part, 311: base part, 312: protrusion part,
32: slit forming part, 32a: slit, 321: flange part,
33: Space forming part,
4: cover member, 4a: cover space, 4b: gap

Claims (1)

A breather device that releases air inside the case to the outside in response to an increase in internal pressure of the case in which the speed change mechanism of the transmission is housed,
A cylindrical member that opens up and down and forms a breather space that communicates with the internal space of the case below;
A valve member made of an elastic material provided at an upper end portion of the cylindrical member so as to close an upper end opening of the cylindrical member;
A cover member that covers the valve member, forms a cover space between the valve member, and forms a gap for communicating the cover space with the outside;
With
The valve member is
A seal portion disposed at the upper end of the cylindrical member;
Extending upward from the seal portion above the breather space so that one direction in a plan view is the longitudinal direction, closes the upper end opening of the cylindrical member together with the seal portion, extends along the longitudinal direction, and the upper end is the A slit forming portion provided with a slit facing the cover space and having a lower end above the upper end opening and facing the breather space;
Have
The valve member or the cover member has a space forming part that forms a part of the cover space above the slit,
The said slit opens according to the raise of the internal pressure of the said case, and connects the said breather space and the said cover space, The breather apparatus characterized by the above-mentioned.