JP6217364B2 - duct - Google Patents

Description

  The present invention relates to a duct. The duct of the present invention is suitably used as an air conditioning duct installed below a vehicle instrument panel.

  An air conditioning unit is arranged below the instrument panel of the vehicle. In order to guide to the discharge port, an air conditioning duct is arranged between the air conditioning unit and the instrument panel (Patent Document 1).

JP 2012-207837 A

  The shape of the air-conditioning duct is different for each vehicle type, but as an example, there is a structure as shown in FIG. Such an air-conditioning duct 1 includes a cylindrical duct body 3, and the duct body 3 is provided at an airflow inlet 5 provided on the lower surface of the duct body 3 and at a position facing the airflow inlet 5. The airflow branch 7 provided by denting the upper surface of the duct body 3 downward, the four airflow outlets 9 through which the airflow branched by the airflow branch 7 is discharged, and the airflow branch 7 And a support wall 11 provided on one side surface of the duct main body 3. The support wall 11 is provided with a projection 13 used when the duct body 3 is fixed to the vehicle.

  The air-conditioning duct 1 having such a configuration can be manufactured by blow molding. When the duct main body 3 obtained by blow molding is taken out of the mold and cooled, the duct main body 3 is shown by an arrow in FIG. There was a case where it bent in the X direction.

  The reason for this bending is that the support wall 11 is provided only on one side surface of the duct body 3 and the shrinkage of the resin during cooling is assumed to be uneven. We thought to provide support walls on the side. However, the other side surface of the duct body 3 is a cable passage, and if a support wall is provided at this position, there is a problem that a change in the cable handling becomes necessary. Therefore, it is necessary to suppress the bending deformation of the duct body 3 by another means.

  This invention is made | formed in view of such a situation, and provides the duct which has a duct main body which can suppress the bending deformation at the time of the cooling after blow molding.

  According to the present invention, the duct includes a cylindrical duct body, and the duct body has an airflow inlet provided on a lower surface of the duct body, and the duct body at a position facing the airflow inlet. An airflow branch provided by denting the upper surface of the airflow downward, at least two airflow outlets for discharging the airflow branched by the airflow branch, and the airflow branch A support wall provided on one side of the duct body, and a duct having a step formed by denting the duct body at a position facing the support wall on the other side of the duct body. Is provided.

  The present inventor conducted intensive studies on a method for suppressing the bending of the duct body, and came up with the idea of forming a stepped portion by denting the duct body instead of providing a support wall on the other side of the duct body. When the duct body provided with such a step portion was manufactured by blow molding, bending deformation could be suppressed.

Hereinafter, various embodiments of the present invention will be exemplified. The following embodiments can be combined with each other.
Preferably, the step portion is provided such that a standing wall extending in the longitudinal direction of the duct body is formed.
Preferably, the step portion is provided on the airflow branching portion and the inclined portions on both sides adjacent to the airflow branching portion.

The duct 1 for air-conditioning of one Embodiment of this invention is shown, (a) is the perspective view seen from the upper surface side, (b) is the perspective view seen from the lower surface side. It is a perspective view in the approximate center section of the front-back direction of the air-conditioning duct 1 of FIG. It is an enlarged view of the area | region containing the airflow branch part 7 of the duct 1 for an air conditioning of FIG. (A)-(c) is a perspective view in section AC of Drawing 3, respectively. In the manufacturing process of the air conditioning duct 1 in FIG. 1, a process of bringing the molten resin sheets 23 and 24 into close contact with the molds 21 and 22 is shown. It is a figure which shows the manufacturing process of the duct 1 for an air conditioning following FIG. 5, and shows the state after the mold clamping of a metal mold | die. It is a perspective view corresponding to Drawing 1 (a) showing air-conditioning duct 1 of a reference example.

  Hereinafter, the present invention will be described by taking an air conditioning duct installed below the instrument panel of the vehicle as an example. The present invention provides a general solution for suppressing bending deformation that occurs during cooling after blow molding, and the present invention provides various ducts or other structures that can be produced by blow molding. It can also be applied to the body. In the following embodiments, description will be made by taking a foam duct as an example, but the present invention can also be applied to a non-foam duct.

  As shown in FIGS. 1A to 1B, an air conditioning duct 1 according to an embodiment of the present invention includes a cylindrical duct body 3, which is provided on the lower surface of the duct body 3. The airflow inlet 5 and the four airflow outlets 9 are provided. The air conditioning duct 1 is installed at the lower part of the instrument panel of the vehicle, and an air conditioning unit (not shown) is installed below the air conditioning duct 1. The airflow P from the air conditioning unit flows into the duct body 3 through the airflow inlet 5 and is discharged from the four airflow outlets 9 as the airflow Q. A packing 6 is provided around the airflow inlet 5 to prevent airflow leakage at the connection with the air conditioning unit. In the present embodiment, two airflow outlets 9 are provided on the right side and the left side of the airflow branching portion 7, but at least one location may be provided on each of the right and left sides of the airflow branching portion 7.

  The duct main body 3 has a substantially symmetrical shape with respect to the central plane in the longitudinal direction, and the airflow inlet 5 is provided at the approximate center in the longitudinal direction of the duct main body 3. As shown in FIG. 2, the upper surface of the duct main body 3 is inclined so as to be lowered toward the airflow branching portion 7 provided at substantially the center in the longitudinal direction of the duct main body 3. For this reason, as for the duct main body 3, the both-sides part of the airflow branch part 7 is the inclination part 3a. In this way, the airflow branching portion 7 is formed by denting the upper surface of the duct body 3 downward at a position facing the airflow inlet 5. The airflow flowing into the duct body 3 from the airflow inlet 5 is branched to the right side and the left side of the airflow branching section 7 as shown in FIG.

  As shown in FIGS. 2 to 3, a support wall 11 is provided on one side surface (front side surface) of the duct body 3 so as to straddle the airflow branching portion 7. By providing the support wall 11, the duct body 3 is prevented from being bent at the airflow branching portion 7 when a force in the direction indicated by the arrow Q in FIG. 2 is applied to the duct body 3. As shown in FIGS. 3 to 4, a step 15 is provided on the other side surface (rear side surface) of the duct body 3. The step portion 15 is provided such that a standing wall 15 a extending in the longitudinal direction of the duct body 3 is formed. Further, the step portion 15 is provided in the airflow branching portion 7 and the inclined portions 3a on both sides adjacent thereto. With such a configuration, the duct body 3 is suppressed from bending in the direction of the arrow X in FIG.

  The support wall 11 is provided with a protrusion 13, and the duct body 3 can be fixed to the vehicle by engaging the protrusion 13 with an engagement recess on the vehicle side. In addition, the method of fixing the duct main body 3 to a vehicle main body is not specifically limited, The protrusion 13 can be abbreviate | omitted when unnecessary.

  Next, the manufacturing method of the air-conditioning duct 1 of this embodiment is demonstrated using FIGS. 5 to 6 schematically show a portion corresponding to a portion including the airflow branching portion 7 in a mold for manufacturing the duct body 3 of the air conditioning duct 1. It does not exactly correspond to the shape of the duct body 3 shown in FIG.

  In order to manufacture the duct body 3 of the present embodiment, as shown in FIG. 5, a pair of molds 21 and 22 corresponding to the shape of the duct body 3 is prepared, and a foamed molten resin sheet (parison) 23, By sucking 24 from the molds 21 and 22 side, the molten resin sheets 23 and 24 are brought into close contact with the molds 21 and 22. Since the mold 21 is provided with the convex portions 21a corresponding to the inclined portions 3a and the airflow branching portions 7, the molten resin sheet 23 is deformed into a shape corresponding to the inclined portions 3a and the airflow branching portions 7. Although not shown, the mold 21 is also provided with an uneven shape corresponding to the support wall 11 and the step portion 15, and the molten resin sheet 23 is deformed into a shape corresponding to the support wall 11 and the step portion 15. Is done. The mold 22 is provided with a recess 22 a corresponding to the air flow inlet 5, and the molten resin sheet 24 is formed with a recess 24 a corresponding to the air flow inlet 5. The molds 21 and 22 are provided with pinch-off portions 21b and 22b so as to surround a cavity 25 formed inside the molds 21 and 22.

  Next, as shown in FIG. 6, the molds 21 and 22 are clamped, and air is blown into the cavities 25 formed inside the molds 21 and 22, so that the inclined part 3a, the airflow branching part 7, The duct main body 3 including the support wall 11 and the step portion 15 is formed. Moreover, the molten resin sheets 23 and 24 are sandwiched and crushed by the pinch-off portions 21 b and 22 b, and a portion of the molten resin sheets 23 and 24 outside the cavity 25 becomes a burr 26.

  Next, the molds 21 and 22 are opened, the molded duct body 3 is taken out, and the duct body 3 is cooled. When the duct body 3 does not include the stepped portion 15, the duct body 3 may be bent and deformed when the duct body 3 is cooled. In this embodiment, the support wall is sandwiched between the duct body 3. Since the step portion 15 is provided at a position opposed to 11, the bending deformation of the duct body 3 is suppressed. After cooling the duct body 3, the air-conditioning duct 1 having the duct body 3 having the configuration of the present embodiment is performed by removing the burrs 26 and drilling to form the airflow inlet 5 and the airflow outlet 9. Is obtained. The packing 6 may be disposed in the mold 22 in advance before blow molding, and may be attached to the molten resin sheet 24 at the time of blow molding, or may be attached after the duct body 3 is manufactured. It is not essential to suck the molten resin sheets 23 and 24 from the molds 21 and 22 side, and air may be blown into the cavity 25 without performing suction.

1: air-conditioning duct, 3: duct body, 5: airflow inlet, 7: airflow branch, 9: airflow outlet, 11: support wall, 15: step

Claims (3)

A duct comprising a cylindrical duct body,
The duct body includes an airflow inlet provided on the lower surface of the duct main body, and an airflow branching portion provided by denting the upper surface of the duct main body downward at a position facing the airflow inlet. And at least two airflow outlets for discharging the airflow branched by the airflow branching portion, and a support wall provided on one side of the duct body so as to straddle the airflow branching portion,
On the other side of the duct body, a step portion formed by denting the duct body at a position facing the support wall is provided,
The step portion is provided so as upright wall extending in the longitudinal direction of the duct body is formed, da transfected. A duct comprising a cylindrical duct body,
The duct body includes an airflow inlet provided on the lower surface of the duct main body, and an airflow branching portion provided by denting the upper surface of the duct main body downward at a position facing the airflow inlet. And at least two airflow outlets for discharging the airflow branched by the airflow branching portion, and a support wall provided on one side of the duct body so as to straddle the airflow branching portion,
On the other side of the duct body, a step portion formed by denting the duct body at a position facing the support wall is provided,
The stepped portion is provided with the air flow branch portion is provided on the inclined portions on both sides adjacent thereto, da transfected. The duct according to claim 1, wherein the stepped portion is provided at the airflow branching portion and the inclined portions on both sides adjacent to the airflow branching portion.