JP2013131448A - Lens cover for vehicular lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to manufacture a lens cover for a vehicle lamp formed by injection molding at a low manufacturing cost by effectively utilizing a molding material and reducing the number of man-hours in its subsequent processes after molding.SOLUTION: In the lens cover 3 for a vehicular lamp 1 including a design face part 6 transmitting emission light from a light source and a ring-shaped upright wall part 7 rising from an outer circumferential part of the design face part 6, there is provided a column-like bumper support part 9f protruding from the upright wall part 7 positioned in a lower side of the design face part 6 to an irradiation direction of the vehicular lamp 1 and the bumper support part 9f is molded by a sprue of a molding die at the time of injection-molding of the lens cover 3. The bumper support part 9f functions as a fulcrum for deciding a vertical position of a bumper relative to the lens cover when the bumper is mounted on a vehicle body.

Description

  The present invention relates to a lens cover for a vehicular lamp, and more particularly to a lens cover for a vehicular lamp formed by resin injection molding.

  In recent years, vehicular lamps (particularly headlamps) have been increased in size and shape by accommodating a plurality of light sources inside, and accordingly, the lens cover constituting the vehicular lamp has also increased in size, It has a slanted (tilted) shape in the vehicle height direction and the vehicle width direction. In addition, the surface (design surface) through which the irradiation light passes is made thinner than the other portions in order to suppress light transmission loss and ensure high light transmittance.

  Such a lens cover is generally formed by injection molding using a polycarbonate resin excellent in various properties such as transparency, impact resistance, weather resistance, and heat resistance. However, the polycarbonate resin also has a problem that the melt viscosity at the time of injection molding is high and the fluidity is not good. Therefore, in order to shorten the flow length of the molten molding material and fill the entire cavity with the molding material before solidifying the molten material, and shorten the molding cycle to increase production efficiency and improve the quality of the molded product, It is conceivable that the molding material to be filled is injected into the cavity from the portion of the cavity where the thin portion that becomes the design surface of the molded product is formed.

  In that case, a pressing mark (gate mark) by the tip of the valve pin of the valve gate remains clearly on the design surface of the molded product, which disturbs the optical path of the transmitted irradiation light and makes it optical in the light distribution characteristics of the vehicle lamp. This adversely affects the appearance of the vehicle lamp and impairs the appearance of the vehicle lamp.

  Therefore, in order to prevent such a problem, the molding resin is covered with the vehicle body when it is mounted on the vehicle at a portion other than the portion of the cavity that forms the design surface of the lens cover and the vehicle lamp is mounted on the vehicle. It is conceivable to inject from an invisible part.

  As a specific example, Patent Document 1 proposes a lens cover (resin cover) by a molding method shown in FIGS.

  A cavity 83 for molding a resin cover is formed in an injection mold 82 in which a fixed mold 80 and a movable mold 81 are clamped, and a sprue 84 connected to a nozzle of an injection molding machine is formed in the cavity 83. A runner 85 connected to the sprue 84 is connected via a fan gate 86.

  At this time, the fan gate 86 connected to the cavity 83 is provided at a portion of the cavity 83 where a flange portion for the gate is formed to protrude from the outer peripheral edge portion of the resin cover (see FIG. 9).

  As a result, the molded product taken out from the molding die after injection molding is solidified in the sprue 84 and the portion 90 solidified in the fan gate 86, the portion 91 solidified in the runner 85, and the portion used as a resin cover. The part 92 is integrally formed (see FIG. 10).

JP 2010-153300 A

  Therefore, in order to use the molded product as a resin cover for a vehicular lamp, it is necessary to perform a post-process work to cut off portions 90, 91, 92 other than the resin cover 93 from the molded product. As a result, the number of manufacturing steps increases, the production efficiency decreases, and the manufacturing cost increases.

  In addition, the part cut out from the molded product becomes a useless part unrelated to the product, which leads to an increase in manufacturing cost due to the use of a useless molding material, and goes against resource saving of the material (injection molding material). Become.

  Therefore, the present invention was devised in view of the above problems, and its object is to use a lens cover for a vehicular lamp, which is formed by injection molding, for the effective use of molding materials and the post-molding post-process. It is to enable manufacturing at a low manufacturing cost by reducing man-hours.

  In order to solve the above-described problem, the invention described in claim 1 of the present invention is a lens cover for a vehicle lamp that transmits light emitted from a light source and irradiates the vehicle lamp outside the vehicle lamp. The cover has a design surface portion that transmits light emitted from the light source, and an annular standing wall portion that rises from an outer peripheral edge portion of the design surface portion, and the irradiation direction of the vehicular lamp from the standing wall portion that is positioned below the design surface portion The bumper support portion is a sprue portion formed by a sprue of a molding die when the lens cover is injection molded.

  The invention described in claim 2 of the present invention is characterized in that, in claim 1, the bumper support portion has a conical shape or a truncated cone shape having a length in a range of 17 to 70 mm. is there.

  According to a third aspect of the present invention, in the first or second aspect, when the bumper support portion is mounted on a vehicle body, the bumper support portion is provided at a position above and below the bumper with respect to the lens cover. It functions as a positioning fulcrum.

  The lens cover of the vehicular lamp according to the present invention includes a design surface portion that transmits light emitted from a light source, and an annular standing wall portion that rises from the outer peripheral edge of the design surface portion, and the vehicle from the standing wall portion that is positioned below the design surface portion. A columnar bumper support part protruding in the irradiation direction of the lamp is provided, and the bumper support part is formed by a sprue of a molding die when the lens cover is injection molded. The bumper support portion functions as a positioning fulcrum for the bumper when the vehicle lamp is mounted on the vehicle body. Thereby, the gap (D2) between the lens cover and the bumper is kept constant.

  As a result, the lens cover of the vehicular lamp according to the present invention can be manufactured at an inexpensive manufacturing cost by reducing the man-hours in the post-process after molding, while at the same time promoting effective use of the molding material and promoting resource saving. It becomes possible.

It is a schematic explanatory drawing of the vehicle lamp using the lens cover of embodiment. It is explanatory drawing which shows the vehicle mounting state of the lens cover of embodiment. It is explanatory drawing which shows the injection molding method of the lens cover of embodiment. Similarly, it is explanatory drawing which shows the injection molding method of the lens cover of embodiment. Similarly, it is explanatory drawing which shows the injection molding method of the lens cover of embodiment. Similarly, it is explanatory drawing which shows the injection molding method of the lens cover of embodiment. Similarly, it is explanatory drawing which shows the injection molding method of the lens cover of embodiment. Similarly, it is explanatory drawing which shows the injection molding method of the lens cover of embodiment. It is explanatory drawing of a prior art example. Similarly, it is explanatory drawing of a prior art example.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to FIGS. 1 to 8 (the same portions are given the same reference numerals). The embodiments described below are preferable specific examples of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention particularly limits the present invention in the following description. Unless stated to the effect, the present invention is not limited to these embodiments.

  FIG. 1 is a schematic explanatory view of a vehicular lamp using the lens cover of the embodiment, and FIG. 2 is an installation explanatory view showing a part of a state in which the vehicular lamp using the lens cover of the embodiment is attached to the vehicle. FIG. 8 is a schematic explanatory view showing an injection molding method of a lens cover constituting the vehicular lamp.

  For example, as shown in FIG. 1, a vehicular lamp (hereinafter abbreviated as “lamp”) 1 has a lens cover 3 mounted on a housing 2 to form a lamp chamber 4, and a light source unit 5 is accommodated in the lamp chamber 4. It becomes the composition.

  The lens cover 3 has an opening at one end, and includes a design surface part 6 that transmits light emitted from the light source part 5 and radiates the light toward the outside, and a standing wall part 7 that is annularly extended from the outer peripheral edge of the design surface part 6. The standing wall portion 7 is a first standing wall portion 8 that becomes a support and fixing portion when the lens cover 3 is supported and fixed to the housing 2, and a support and fixing portion when the lens cover 3 is supported and fixed to the housing 2. It consists of the 2nd standing wall part 9 used as the support part for positioning a bumper after attaching a vehicle lamp to a vehicle.

  Among them, the first standing wall portion 8 rises from the outer peripheral edge portion of the design surface portion 6 and extends to the rear housing 2 side in a partial annular shape (a part of the entire annular shape), and the leg portion 8a side of the housing 2 A flange portion 8b that is bent at the end portion and extends in a partial annular shape in a direction substantially similar to the design surface portion 6 and a seal rib 8c that protrudes in a partial annular shape from the housing 2 side surface of the flange portion 8b to the housing 2 side are provided.

  On the other hand, the second standing wall portion 9 rises from the outer peripheral edge portion of the design surface portion 6 and is bent at the housing 2 side end portion of the first leg portion 9a and the first leg portion 9a extending in a partial annular shape toward the rear housing 2 side. A second leg portion 9b extending in a partial ring shape in a direction substantially the same as the design surface portion 6, and a third leg extending in a partial ring shape toward the housing 2 by bending at the end opposite to the design surface portion 6 of the second leg portion 9b. And a flange portion 9d that is bent at the housing 2 side end portion of the third leg portion 9c and extends in a partial annular shape in a direction substantially similar to the design surface portion 6.

  The flange portion 9d is provided with a seal rib 9e that protrudes in a partial annular shape from the surface on the housing 2 side toward the housing 2, and a columnar bumper support that protrudes from the surface opposite to the housing 2 to the opposite side to the housing 2 A portion 9f is provided.

  That is, the first standing wall 8 and the second standing wall 9 form an annular standing wall 7, and the leg 8 a of the first standing wall 8, the first leg 9 a and the second leg of the second standing wall 9. An annular leg portion 10 is formed by the 9b and the third leg portion 9c, and an annular flange portion 11 is formed by the flange portion 8b of the first standing wall portion 8 and the flange portion 9d of the second standing wall portion 9. An annular seal rib 12 is formed by the seal rib 8 c of the standing wall 8 and the seal rib 9 e of the second standing wall 9.

  The housing 2 has an opening at one end and an annular sealing groove 21 at the opening end 20. The sealing groove 21 is filled with a sealing material 22, and an annular flange portion 11 of the lens cover 3 is provided. By inserting the seal rib 12 into the seal groove 21 and immersing it in the seal material 22, the seal rib 12 of the lens cover 3 is fitted and fixed to the seal groove 21 of the housing 2 via the seal material 22. ing.

  The vehicle lamp having the above-described configuration is attached by the method shown in FIG.

  Specifically, two substantially plate-like bumper support pieces 31 and 32 protruding in the vehicle rearward direction at a predetermined interval in advance are arranged in parallel on the vehicle bumper 30, and the second standing wall portion 9 of the lens cover 3 is arranged. The vehicular lamp 1 is positioned so that the two bumper support pieces 31 and 32 of the bumper 30 are sandwiched from the outside by the bumper support portion 9f of the second standing wall portion 9 of the lens cover 3 in the same manner as the first leg portion 9a. The part is used as a positioning fulcrum of the vertical position of the vehicular lamp 1 with respect to the bumper 30 and is attached by connecting and fixing the connecting members provided on the vehicular lamp 1 and the vehicle body (not shown) with screws or the like. Is done.

  The bumper support portion 9f is preferably a truncated cone shape having a length (L) in the range of 17 to 70 mm in consideration of the shape of the lens cover 3 and the positional relationship with the vehicle body / bumper 30. The diameter (D1) of the tip is φ6.5 mm in the present embodiment.

  By the way, the lens cover 3 has the design surface part 6 which permeate | transmits the light from a light source and irradiates outside as mentioned above. Therefore, it is formed by using a polycarbonate resin that is excellent in transparency and in addition to various performances such as impact resistance, weather resistance, and heat resistance.

  Therefore, the lens cover having such a shape is generally formed by injection molding using a polycarbonate resin. Hereinafter, the injection molding method will be described with reference to FIGS.

  First, in the mold preparing step of FIG. 3, one half 61a of the cavity is formed on the abutting surface 60a side, and the nozzle contact portion 62 communicates with the half cavity 61a and contacts the nozzle of the injection molding machine at the time of injection molding. And a movable mold 50 in which the other half 61b of the cavity is formed on the abutting surface 60b side is prepared.

  Next, in the mold clamping process of FIG. 4, mold clamping is performed in which the butting surfaces 60 a and 60 b of the fixed mold 40 and the movable mold 50 are brought into contact with each other to share the parting line 60.

  Next, in the nozzle contact process of the injection molding machine in FIG. 5, the nozzle 70 of the injection molding machine is inserted into the nozzle contact portion 62 provided in the injection mold 45 by the fixed mold 40 and the movable mold 50 that are clamped. Make contact.

  Next, in the molding resin injection step of FIG. 6, the heated molten resin 72 of the molding material (polycarbonate resin) supplied into the heating cylinder 71 is transferred to the tip of the heating cylinder 71 by the rotation of the screw 73, and the heating cylinder 71. A fixed amount of molten resin 72 accumulated at the tip of the nozzle is injected into the cavity 61 from the nozzle 70 through the sprue 63 by the extrusion pressure (transfer) by the advancement of the screw 73.

  After holding the cavity 61 for a certain period of time after being filled with the molten resin 72, the molten resin 72 in the cavity 61 is cooled, and at the same time, the rotation of the screw 73 causes the molten resin 72 for the next injection molding to occur. It is transferred to the tip of the heating cylinder 71. At this time, the screw 73 moves backward by a transfer force (extrusion force) generated in the molten resin 72 by the rotation of the screw 73 itself (see FIG. 7).

  Next, in the mold opening process of FIG. 8, after the molten resin 72 is cooled and solidified in the cavity 61, the fixed mold 40 and the movable mold 50 are separated, and a molded product 75 attached to the movable mold 50 is obtained. Remove.

  The molded product 75 obtained through the above injection molding process is integrally formed with a sprue portion 76 formed by a sprue 63 that becomes a passage for the molten resin 72 when the molten resin 72 is injected into the cavity 61. Yes. Conventionally, a molded product molded using a molding die is a part or product other than the part formed by the cavity, for example, the sprue portion 76 is cut off in a subsequent process and only the part formed by the cavity 61 is formed. Used as.

  On the other hand, in the present invention, a portion (sprue portion 76) other than the portion formed by the cavity of the molded product 75 is also used as a part or product, and any molded product 75 taken out from the mold after injection molding is used. They are used as parts or products as they are without any post-processing.

  As a result, the lens cover of the vehicular lamp according to the present invention can be manufactured at an inexpensive manufacturing cost by reducing the man-hours in the post-process after molding, while at the same time promoting effective use of the molding material and promoting resource saving. It becomes possible.

  The sprue portion 75 of the injection-molded product 75 forms the bumper support portion 9f of the lens cover 3. When the vehicle lamp 1 using the lens cover 3 is mounted on the vehicle, the bumper of the vehicle bumper 30 is used. Together with the support pieces 31, 32, the vehicle lamp 1 serves as a positioning fulcrum for the vertical position of the vehicular lamp 1 (see FIG. 2).

  Therefore, the sprue 63 provided in the fixed mold 40 has an optimal shape to satisfy them from both the viewpoints related to injection molding and the viewpoint that the sprue portion 76 formed by the sprue 63 functions as a bumper support portion. Set to dimension.

DESCRIPTION OF SYMBOLS 1 ... Vehicle lamp 2 ... Housing 3 ... Lens cover 4 ... Light chamber 5 ... Light source part 6 ... Design surface part 7 ... Standing wall part 8 ... 1st standing wall part 8a ... Leg part 8b ... Flange part 8c ... Seal rib 9 ... 2nd standing wall Part 9a ... First leg part 9b ... Second leg part 9c ... Third leg part 9d ... Flange part 9e ... Seal rib 9f ... Bumper support part 10 ... Leg part 11 ... Flange part 12 ... Seal rib 20 ... Open end 21 ... Seal Groove 22 ... Sealing material 30 ... Bumper 31 ... Bumper support piece 32 ... Bumper support piece 40 ... Fixed mold 45 ... Injection mold 50 ... Movable mold 60 ... Parting line 60a ... Butting surface 60b ... Butting surface 61 ... Cavity 61a ... Half cavity 61b ... Half cavity 62 ... Nozzle contact part 63 ... Sprue 70 ... Nozzle 71 ... Cylinder 72 ... Molded resin 73 ... S Ryu 75 ... the molded article 76 ... sprue portion

Claims (3)

A lens cover for a vehicular lamp that transmits light emitted from a light source and irradiates the vehicular lamp,
The lens cover has a design surface portion that transmits light emitted from the light source, and an annular standing wall portion that rises from an outer peripheral edge portion of the design surface portion,
A columnar bumper support portion protruding in the irradiation direction of the vehicular lamp from a standing wall portion located below the design surface portion;
The lens cover for a vehicular lamp, wherein the bumper support portion is a sprue portion formed by a sprue of a molding die at the time of injection molding of the lens cover.   The lens cover of the vehicular lamp according to claim 1, wherein the bumper support portion has a conical shape or a truncated cone shape having a length in a range of 17 to 70 mm.   3. The vehicular lamp according to claim 1, wherein the bumper support portion functions as a positioning fulcrum of the vertical position of the bumper with respect to the lens cover when the bumper is mounted on a vehicle body. Lens cover.

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