The present invention relates to a check valve structure ventilating fluid from an inside to an outside and preventing the fluid and foreign materials from entering from the outside to the inside.
As a conventional check valve structure, there is, for example, one shown in Patent Document 1. In the conventional check valve structure, there is an air extractor located under a rear bumper cover. The air extractor includes a base layer defining one aperture, a retainer layer defining another aperture corresponding to the one aperture and disposed on the base layer, and three sealing members covering and substantially sealing the one and the another apertures from an outer surface side of the retainer layer. The base layer is affixed to the retainer layer, and two protruding side portions of an upper portion of each of the three sealing members are sandwiched between the base layer and retaining layer such that the three sealing members are capable of rotating between an opening position and a closed position; thereby, in the conventional check valve structure, a fluid communication between the inside and the outside is provided. The three members are moved in the opening position to ventilate the fluid from the inside to the outside, and moved in the closed position to prevent the fluid and foreign materials from entering in the inside.
However, the conventional check valve is complicated and requires a number of components. Therefore, a size of the conventional check valve is likely to be large, and thereby, it causes a high cost.
Also, as other conventional check valve structures, there are one shown in Patent Document 2 and one shown in Patent Document 3. In the other conventional check valve structures, there is a hole plug or a grommet provided to seal a hole of an engaged portion. The hole plug includes a head portion having a flange portion, a support portion circularly downwardly extending from the head portion, erection portions arranged circumferentially around the support portion, and connecting portions each connecting the support portion and the erection portion. The erection portion has an engagement step portion formed along an outer surface portion thereof, and when the hole plug is inserted in the hole of the engaged portion, a peripheral edge portion of the hole is engaged in the engagement step portion to seal the hole.
The grommet in Patent Document 3 includes a head portion having a central member and a non-insertion portion circularly arranged around the central member, and an insertion portion extending circularly downwardly from the head portion and having a mounting hole circularly formed along an outer surface portion of the insertion portion. When the insertion portion is inserted in the hole of the engaged portion, a peripheral edge portion of the hole is engaged in the mounting portion to seal the hole.
However, in the other conventional structures, the hole plug and the grommet do not have any hole communicated to the outside and thereby, the fluid cannot be ventilated from the inside to the outside through the hole plug or the grommet.
In the present invention, a check valve structure ventilates fluid from an inside to an outside and prevents fluid and foreign materials from entering from the outside to the inside, and has compact size and is capable of being manufactured at a low cost.
In the invention, a check valve structure comprises an engaged portion including a hole for ventilating fluid between one side and another side of the engaged portion, the hole including a locking hole and a ventilating hole outwardly circumferentially arranged around the locking hole; and a hole plug including a locking portion inserted in the locking hole to lock the locking portion therein and an outer portion outwardly circumferentially extending from the locking portion to cover the ventilating hole. In the check valve structure, the structure is simple and can be easily attached to the engaged portion, wherein the fluid can flow from the one side to the another side, but the fluid and foreign materials can be prevented from flowing in a direction from the another side to the one side.
The outer portion may include a bendable portion having flexibility. In accordance with the flexibility of the bendable portion, the fluid flows from the one side to the another side.
The ventilating hole may include a plurality of holes, and has an outer circumference smaller than that of the outer portion of the hole plug. That is, the outer portion of the hole plug has an outer circumference larger than that of the ventilating hole to cover the ventilating hole at the one side. In accordance with the outer circumference of the outer portion, the fluid is prevented from flowing in the direction from the another side to the one side.
The locking portion may include a plurality of locking pieces, each having a locking claw outwardly protruding from each of the plurality of locking pieces. The locking claw engages the engaged portion and a circumferential gap is formed therebetween. In accordance with the circumferential gap, the fluid is ventilated from the one side to the another side.
The locking claw may have an elasticity to lock the locking portion in the locking hole. In accordance with the elasticity, the locking portion is tightly locked in the locking hole by the elastic reactive force.
The plurality of locking pieces may be spaced from each other to form a space therebetween, and the space is widened in a direction toward a bottom portion of each of the plurality of locking pieces. In accordance with an arrangement of the plurality of locking pieces, the hole plug is made compact with maintaining flow efficiency of the fluid.
The hole plug may further comprise a protruding portion including a plurality of protrusions arranged around the plurality of locking pieces and protruding from a lower surface of the outer portion. The plurality of protrusions contacts the engaged portion outside the locking hole when the hole plug engages the engaged portion.
Also, the locking claw may be arranged at a position not laterally overlapping with each of the plurality of protrusions.
In accordance with the protruding portion including the plurality of protrusions, a circular gap is circularly formed between the lower surface of the outer portion and the engaged portion by an amount equal to a height of the protruding portion in a protruding direction. Therefore, the fluid can be smoothly ventilated through the gap, and the hole plug is made compact with maintaining flow efficiency of the fluid.
The plurality of locking pieces may be circularly arranged at equal intervals, and the plurality of protrusions is arranged circularly outside the plurality of locking pieces at equal intervals so that each of the plurality of protrusions is located between two of the locking claws, respectively. Each of the plurality of protrusions may have a length in a protruding direction shorter than that of the locking claw.
In accordance with an arrangement of the plurality of locking pieces, the plurality of protrusions and the locking claws, the hole plug is made compact with maintaining flow efficiency of the fluid.
The engaged portion may be a panel, and the hole is formed in the panel. Therefore, the check valve structure can be arranged at an exterior of a vehicle, typically under a rear bumper.
Hereinafter, an embodiment of the present invention will be explained with reference to
Firstly, the hole plug 20 will be explained with reference to
The outer portion 22 includes an inner edge portion 35 arranged along an inner circumference of the outer portion 22, and is bent downwardly in a direction apart from the center portion 21.
The hole plug 20 further includes a locking portion 42 arranged inside the central portion 21. The locking portion 42 is formed with a plurality of locking pieces 41 extending downwardly and inwardly from the inner edge portion 35. The locking piece 41 includes a plurality of surface portions, and the plurality of surface portions includes an inner surface portion 41a extending from the central member 31, an outer surface portion 41b extending from the inner edge portion 35, side surface portions 41c extending from the connecting portion 33, and a bottom surface portion 41d enclosing the inner surface portion 41a, the outer surface portion 41b, and the side surface portions 41c. The inner surface portion 41a is curved such that a distance between the inner surface portion 41a and the outer surface portion 41b becomes narrower in a direction toward the bottom surface portion 41d. The side surface portions 41c connect the inner surface portion 41a and the outer surface portion 41b such that the bottom surface portion 41d is formed as a substantial trapezoid-shape. Also, each of the plurality of surfaces has a shape chamfered with a curved surface around the inner edge portion 35 to avoid a stress concentration.
In the hole plug of the embodiment shown in
The four locking pieces 41 has the same shape, respectively, and arranged apart from each other to form a central space defined by the inner surface portions 41a. Also, the four locking pieces 41 are spaced from each other in a circumferential direction to form a side space therebetween, and the side space is widened in a direction toward a bottom surface 41d of each of the locking pieces 41.
The locking piece 41 includes a locking claw 43 arranged on a center portion of the outer surface portion 41b relative to the circumferential direction and outwardly projecting from the outer surface portion 41b. The locking claw 43 includes a first outer surface 43a at a bottom portion side of the locking piece 41, a second outer surface 43b at an upper portion side of the locking piece 41, and a step surface 43c formed between the first outer surface 43a and the second outer surface 43b. The first outer surface 43a is inclined upwardly in a direction from a bottom end of the first outer surface 43a toward the step surface 43c, and the second outer surface 43b is inclined downwardly in a direction from an upper end of the second outer surface 43b toward the step surface 43c. An inclined angle of the first outer surface 43a from the outer surface 41b is larger than that of the second outer surface 43b from the outer surface 41b. Therefore, the step portion 43c is formed therebetween. The locking claw 43 is integrally formed with the locking piece 41.
The locking portion 42 further includes a circumferential rib 44 connecting two locking pieces 41 adjacent to each other in the side space, and a central rib 45 connecting two locking pieces 41 facing each other in the central space. The circumferential rib 44 may connect the upper portions of the two locking pieces 41 relative to an extending direction, and the central rib 45 may connect the center portions of the two inner surfaces 41a relative to the circumferential direction.
A bottom surface of the central rib 45 is located at a position higher than the step surface 43c of the locking claw 43 in a vertical direction, and the circumferential rib 44 has a height substantially same as that of the central rib 45 in the vertical direction. The central rib 45 is not arranged at a portion overlapped with the connecting portions 33.
In the hole plug of the embodiment shown in
Further, in a hole plug of a modified embodiment shown in
Incidentally, in
In in the hole plug of the modified embodiment shown in
Secondly, the engaged portion 50 will be explained with reference to
In the engaged portion of the embodiment shown in
Also, in the hole plug of the embodiment shown in
Finally, the check valve structure 10 will be explained with reference to
The locking portion 42 is inserted in the locking hole 51 such that the hole plug 20 and the engaged portion 50 are engaged. At this time, since the locking portion 42 is formed of an elastic material, the locking portion is deformed elastically to be inserted in the locking hole 51. Also, since the plurality of locking pieces 41 is connected each other through the circumferential ribs 44 and the central rib 45, the plurality of locking pieces 41 is deformed integrally each other, and since the locking claws 43 are also formed of an elastic material, the locking claws 43 are integrally elastically deformed with the plurality of locking pieces 41.
When the locking portion 42 is inserted in the locking hole 51, the step surface 43c of the locking claw 43 contacts a lower surface of the annular portion 52, the second outer surface 43b contacts the inner circumference of the annular portion 52, and the locking claws elastically abut against the annular portion 52 with an elastic reactive force toward the inner circumference of the annular portion 52. Thereby, the locking portion 42 is locked in the locking hole 51.
When the locking claws abut against the annular portion 52, as shown in
Further, in the hole plug of the modified embodiment shown in
The protrusion 47, forming the protruding portion 46, may have a round shape portion at a front end thereof to easily support the annular portion 52.
In the hole plug of a modified embodiment shown in
Since the circular gap 62 is communicated with the circumferential gap 63, the fluid can be ventilated through the circular gap 62 and the circumferential gap 63 from the inside to the outside. Also, the outer portion 21 includes a bendable portion 61 having a flexibility around the inner edge portion 35. When the locking portion 42 is inserted in the locking hole 51, the bendable portion 61 is bent by contacting the upper surface of the engaged portion 50. In the hole plug of the modified embodiment shown in
The outer portion 22 has an outer circumference larger than the ventilating holes 54 in a radial direction. Therefore, the outer portion 22 covers the ventilating holes 54, and the check valve structure 10 prevents the fluid and foreign materials, such as water and small particles, from flowing in a direction from the outside to the inside. The outer portion 22 may have an outer circumference substantially covering the ventilating hole; thereby, the hole plug 20 is made compact with maintaining flow efficiency of the fluid.
Further, in the hole plug of the modified embodiment shown in
While the invention is explained with reference to the specific embodiment of the present invention, the explanation is illustrative and the invention is limited only by the appended claims.