Lens member for vehicle lamp, and method for manufacturing same

Abstract

Provided is a lens member for a vehicle lamp that inhibits a resin that forms an outer frame portion from entering a light-transmitting region of a lens portion and inhibits the appearance of streaks in the light-transmitting region.　A lens member 1 of a vehicle lamp comprises: a lens portion 10 that transmits light; and an outer frame portion 20 that overlaps along the outer periphery of the lens portion 10 and has an integrated portion 21 that is integrated with the lens portion 10, wherein the lens portion 10 includes an inner region 11 that has a first thickness T1, an intermediate region 12 that is provided along the outer periphery of the inner region 11 and defines a tip position 21A of the integrated portion 21, and an outer region 13 that is provided along the outer periphery of the intermediate region 12 and overlaps the integrated portion 21, the intermediate region 12 gradually becoming thinner toward the inner region 11 from a second thickness T2 on the tip position 21A side to the first thickness T1, the second thickness T2 being thicker than the first thickness T1.

Description

Lens member for vehicle lamp and method for manufacturing the same

[0001] The present invention relates to a lens member for a vehicle lamp and a manufacturing method for manufacturing a lens member for a vehicle lamp including a lens part and an outer frame part by multi-color molding.

[0002] The two-color molding technology is used, for example, when producing a light-transmitting cover of a lamp such as a headlamp of a vehicle. And in this two-color molding, in order to regulate the region where the colored resin is filled in the mold after forming a primary molded product made of a transparent resin, not only the mold but also the ridge partition provided on the back surface of the primary molded product is used.

[0003] However, in a secondary molded product in which a weld is formed in the vicinity of the ridge partition, if gas cannot be discharged well from this ridge partition, bubbles will remain in the secondary molded product or underfilling will occur.

[0004] As a result, the bonding strength between the primary molded product and the secondary molded product decreases, or appearance defects of the two-color molded product occur.

[0005] Therefore, Patent Document 1 discloses a two-color molded product including a first resin part having a predetermined shape and a second resin part in contact with at least a part of the first resin part so as to overlap. The first resin part has a ridge part formed on the back surface side in contact with the second resin part. The second resin part has a contact part in contact with the side surface of the ridge part and a covering part protruding from the contact part so as to cover a part of the upper surface of the ridge part. The covering part is formed in the vicinity of the weld line of the second resin part among the upper surface of the ridge part, and the protruding amount decreases as it moves away from the weld line in a direction intersecting the weld line. Specifically, the first resin part is the light-transmitting part of the cover for the vehicle lamp, and the second resin part is made of a colored resin.

[0006] Furthermore, Patent Document 1 discloses a method for manufacturing a two-color molded product, comprising: a first step of injecting a first resin material into a first cavity formed by a first core mold and a cavity mold to form a first resin part of a predetermined shape; and a second step of clamping a second core mold and a cavity mold, which have a different shape from the first core mold, so that at least a part of the first resin part is exposed, with the first resin part positioned inside the cavity mold, and injecting a second resin material into a second cavity formed by the second core mold and cavity mold to form a second resin part that joins with at least a part of the first resin part, wherein the first step forms a first resin part having a protruding portion on the side that contacts the second resin part, and the second step injects a second resin material with the protruding portion and the second core mold in contact, to form a second resin part having a covering portion that covers a part of the upper surface of the protruding portion.

[0007] Patent No. 6775994

[0008] Incidentally, when molding lens components for vehicle lighting fixtures using multi-color molding, if a step is created in the lens portion to prevent the resin forming the outer frame portion that overlaps along the outer circumference of the light-transmitting lens portion from penetrating the light-transmitting area of ​​the lens portion, the boundary between the thickened portion that forms the step and the basic thickness portion of the thinner lens portion may be located within the light-transmitting area, and this boundary may be visible as a streak (shadow).

[0009] This invention has been made in view of these circumstances, and one of its objectives is to provide a lens member for a vehicle lamp that suppresses the penetration of the resin forming the outer frame into the light-transmitting region of the lens, while also suppressing the appearance of streaks in the light-transmitting region, and a method for manufacturing the same.

[0010] The present invention is understood to achieve the above objective by the following configuration. The lens member of the present invention is a lens member for a vehicle lamp, and the lens member comprises a light-transmitting lens portion and an outer frame portion having an integrated portion that overlaps along the outer circumference of the lens portion and integrates with the lens member, and the lens portion comprises an inner region of a first thickness, an intermediate region provided along the outer circumference of the inner region and defining the tip position of the integrated portion, and an outer region provided along the outer circumference of the intermediate region and overlapping with the integrated portion, wherein the intermediate region gradually thins out toward the inner region from a second thickness on the tip position side which is thicker than the first thickness, to the first thickness.

[0011] The present invention provides a method for manufacturing a lens member of a vehicle lamp, comprising a lens portion and an outer frame portion, by multi-color molding, comprising: a first molding step of molding the light-transmitting lens portion; and a second molding step of molding the outer frame portion having an integrated portion that overlaps along the outer circumference of the lens portion and integrates with the lens portion, wherein the first molding step is a step of molding the lens portion by supplying a light-transmitting resin into a mold, and the mold comprises: an inner space having a first width corresponding to the inner region of the lens portion having a first thickness; an intermediate space provided along the outer circumference of the inner space and corresponding to an intermediate region of the lens portion that defines the tip position of the integrated portion; and an outer space provided along the outer circumference of the intermediate space and corresponding to the outer region of the lens portion that overlaps with the integrated portion, wherein the intermediate space is a space in which the width gradually narrows toward the inner space, from a second width on the side corresponding to the tip position, which is wider than the first width, to the first width.

[0012] According to the present invention, a lens member for a vehicle lamp is provided that suppresses the penetration of the resin forming the outer frame into the light-transmitting region of the lens, while also suppressing the appearance of streaks in the light-transmitting region, and a method for manufacturing the same.

[0013] This is a top view showing a vehicle equipped with a lens member of a vehicle lamp according to the first embodiment of the present invention. This is a perspective view showing only the lens member of the vehicle lamp according to the first embodiment of the present invention. This is a cross-sectional view taken along line A-A in Figure 2. This is a partially enlarged view of Figure 3. This is a diagram illustrating the mold used in the first molding step for forming the lens portion of the first embodiment of the present invention. This is a partially enlarged view of Figure 5. This is a diagram illustrating the mold used in the second molding step for forming the outer frame portion integrated with the lens portion of the first embodiment of the present invention. This is a partially enlarged view of Figure 7. This is a diagram showing a lens member with a conventional structure. This is a view of the surface side of the lens member of the first embodiment of the present invention and the lens member with a conventional structure shown in Figure 9. This is a diagram illustrating the lens member of a vehicle lamp according to the second embodiment of the present invention.

[0014] Hereinafter, embodiments for carrying out the present invention (hereinafter referred to as "embodiments") will be described in detail with reference to the attached drawings. Throughout the description of the embodiments, the same elements are denoted by the same numbers or reference numerals.

[0015] However, please note that, for the sake of readability, not all elements of the same type are assigned numbers or symbols, and some elements do not have numbers or symbols assigned. Also, in order to make the explanation easier to understand, some parts of the structure are emphasized, and dimensions may differ from actual dimensions.

[0016] <<First Embodiment>> The lens member 1 of a vehicle lamp according to the first embodiment of the present invention and its manufacturing method will be described below.

[0017] Figure 1 is a top view showing a vehicle C equipped with a lens member 1 of a vehicle lighting device according to a first embodiment of the present invention.

[0018] Figure 2 is a perspective view showing only the lens member 1 of a vehicle lamp according to the first embodiment of the present invention, and is a perspective view showing the outer surface of the lens member 1 when it is attached to the vehicle C.

[0019] Figure 3 is a cross-sectional view taken along line A-A in Figure 2. Figure 4 is a magnified view of a part of Figure 3, specifically a magnified view of the area indicated by the circled B in Figure 3.

[0020] In the following, the side of the lens component 1 that faces outward when attached to vehicle C will be referred to as the front surface, and conversely, the side that faces inward when attached to vehicle C will be referred to as the back surface.

[0021] Furthermore, in the following, the side of the lens component 1 that faces outward when attached to vehicle C will be referred to as the front side, and the side that faces inward when attached to vehicle C will be referred to as the back side.

[0022] Furthermore, in the description of the molding die, the terms "front side" and "back side" will be used based on whether the surface (front side) or the back side (back side) of the lens member 1 is being molded.

[0023] As shown in Figure 1, the lens member 1 of the vehicle lighting device in the first embodiment is the outer lens of a headlight provided on the front side of the vehicle C.

[0024] However, it is not limited to outer lenses; it may also be used in inner lenses, or in vehicle lighting fixtures installed in locations other than headlights (for example, taillights, etc.).

[0025] As shown in Figure 2, the lens member 1 comprises a lens portion 10 molded from a light-transmitting transparent resin, and an outer frame portion 20 located on the back side of the lens portion 10 and molded from a light-impermeable colored resin.

[0026] As can be seen in Figure 3, the outer frame portion 20 overlaps with the outer circumference of the lens portion 10 and has an integrated portion 21 that integrates with the lens portion 10, and this integrated portion 21 is located in the outer region 13 (described later) on the back side of the lens portion 10.

[0027] As shown in Figures 3 and 4, the lens portion 10 comprises an inner region 11, an intermediate region 12 provided along the outer circumference of the inner region 11 and defining the tip position 21A of the integrated portion 21 of the outer frame portion 20, and an outer region 13 provided along the outer circumference of the intermediate region 12 and overlapping with the integrated portion 21.

[0028] As shown in Figure 4, the inner region 11 has a nearly constant first thickness T1. Also, as shown in Figure 4, the thickness of the intermediate region 12 at the boundary with the inner region 11 is nearly the same as the first thickness T1 of the inner region 11.

[0029] On the other hand, as shown in Figure 4, the intermediate region 12 has a second thickness T2 at its outermost position, which is the boundary with the outer region 13, and this second thickness T2 portion protrudes on the back side of the lens portion 10, defining the tip position 21A of the integrated portion 21 of the outer frame portion 20.

[0030] As shown in Figure 4, the intermediate region 12 gradually thins out toward the inner region 11, from a second thickness T2 at the tip position 21A, which is thicker than the first thickness T1, to a first thickness T1.

[0031] Specifically, the intermediate region 12 is designed so that, toward the inner region 11, the thickness decreases at a nearly constant rate, from a second thickness T2 at the tip position 21A, which is thicker than the first thickness T1, to the first thickness T1.

[0032] In this way, by gradually reducing the thickness, a large change in thickness does not occur at the boundary between the intermediate region 12 and the inner region 11, thus suppressing the appearance of streaks associated with abrupt changes in thickness.

[0033] For example, in the first embodiment, the intermediate region 12 has a first length L that extends from a second thickness T2 to a first thickness T1, and this first length L is 10 times or more the difference between the second thickness T2 and the first thickness T1.

[0034] Furthermore, by multiplying the difference in thickness by a length of more than 10 times, and reducing the thickness at a nearly constant rate, the angle θ on the inner region 11 side of the triangular protrusion 12A formed on the back side of the intermediate region 12, which is thicker than the first thickness T1, becomes a small angle of less than approximately 6°, and the intermediate region 12 and the inner region 11 become connected without a large change in thickness that is close to a step.

[0035] Furthermore, this angle θ is considered acceptable as long as it is less than 15°, preferably less than 10°, and even more preferably less than 6° as described above.

[0036] On the other hand, as mentioned above, the intermediate region 12 is a part with a change in thickness, and therefore, the light incident on it may not be directed in the target illumination direction on the front side of the vehicle C. For this reason, in order to prevent the range of the intermediate region 12 from becoming too wide, it is preferable that the first length L of the intermediate region 12 is not too long.

[0037] As mentioned above, it is preferable that the first length L is 10 times or more the difference between the second thickness T2 and the first thickness T1. Therefore, in order to avoid increasing the length of the first length L, it is preferable that the difference between the second thickness T2 and the first thickness T1 be small.

[0038] Therefore, it is preferable that the second thickness T2 be such that the difference between the second thickness T2 and the first thickness T1 is within 1 mm.

[0039] Furthermore, if the difference between the second thickness T2 and the first thickness T1 is within 1 mm, then, as described above, considering the connection between the intermediate region 12 and the inner region 11 without a large change in thickness that is close to a step, it is preferable to set the first length L to 10 mm or more to suppress the occurrence of ribs, while keeping the first length L within 20 mm so that the range of the intermediate region 12 does not become too wide.

[0040] Furthermore, if the difference between the second thickness T2 and the first thickness T1 is 0.1 mm or more, the tip position 21A of the integrated portion 21 can be sufficiently defined.

[0041] Next, a manufacturing method for producing the lens member 1 described above by multi-color molding will be explained. The manufacturing method for producing the lens member 1 of the first embodiment by multi-color molding comprises a first molding step of molding a light-transmitting lens portion 10, and a second molding step of molding an outer frame portion 20 having an integrated portion 21 that overlaps along the outer circumference of the lens portion 10 and integrates with the lens portion 10. First, the first molding step will be explained.

[0042] FIG. 5 is a diagram for explaining a molding die M1 of a first molding step for molding the lens unit 10 according to the first embodiment of the present invention, and is a cross-sectional view of the molding die M1 of a portion corresponding to the cross-section of the lens unit 10 in FIG. 3.

[0043] The first molding step is a step of supplying a resin capable of transmitting light into the molding die M1 to mold the lens unit 10. As shown in FIG. 5, it includes a first molding surface die M11 corresponding to the front surface side of the lens unit 10 and a first molding back surface die M12 corresponding to the back surface side of the lens unit 10.

[0044] When the surface die M11 and the back surface die M12 are combined, a space SP1 corresponding to the shape of the lens unit 10 is formed in the molding die M1. A transparent resin that transmits light and serves as the material of the lens unit 10 is poured into the space SP1. After the resin hardens, the back surface die M12 is removed, and the second forming step, which is the next process, is performed while the lens unit 10 is held by the surface die M11.

[0045] FIG. 6 is a partially enlarged view of FIG. 5 and is an enlarged view of the portion indicated by the circular enclosure MB1. As shown in FIG. 6, the molding die M1 has an inner space SP11 having a first width W1 corresponding to the inner region 11 of the lens unit 10 with a first thickness T1 as a space SP1 for pouring a transparent resin, an intermediate space SP12 provided along the outer periphery of the inner space SP11 and corresponding to the intermediate region 12 of the lens unit 10 that defines the tip position 21A of the integrated portion 21, and an outer space SP13 provided along the outer periphery of the intermediate space SP12 and corresponding to the outer region 13 of the lens unit 10 that overlaps with the integrated portion 21.

[0046] In the first embodiment, the integrated portion 21 of the outer frame portion 20 is located in the outer region 13 on the back surface side of the lens unit 10. Correspondingly, a protruding space SP121 that protrudes in a direction corresponding to the back surface side of the lens unit 10 is formed so that a portion with a second width W2 forms a protrusion that defines the tip position 21A of the intermediate region 12.

[0047] Further, since the space SP1 into which the transparent resin is poured is a space SP1 that substantially coincides with the outer shape of the lens portion 10, the intermediate space SP12 gradually narrows from the second width W2 on the side corresponding to the tip position 21A side of the integrated portion 21 of the outer frame portion 20 that is wider than the first width W1 toward the inner space SP11 to become the first width W1.

[0048] Further, the intermediate space SP12 has a first length SPL from the second width W2 to the first width W1, and it is preferable that the first length SPL is 10 times or more the difference obtained by subtracting the first width W1 from the second width W2.

[0049] More specifically, the second width W2 is a width such that the difference obtained by subtracting the first width W1 from the second width W2 is within 1 mm, and it is preferable that the first length SPL is within 10 mm and 20 mm.

[0050] Then, after forming the lens portion 10 using the mold M1 as described above, as described above, after removing the back mold M12, in the state where the lens portion 10 is held by the front mold M11, the second forming step, which is the next step, is performed.

[0051] Next, the second molding step for molding the outer frame portion 20 integrated with the lens portion 10 according to the first embodiment of the present invention will be described.

[0052] FIG. 7 is a diagram for explaining a mold M2 for the second molding step of molding the outer frame portion 20 integrated with the lens portion 10 according to the first embodiment of the present invention, and is a cross-sectional view of the mold M2 of the portion corresponding to the cross-section of the lens member 1 in FIG. 3.

[0053] The second molding step is a step of supplying resin into a mold M2 including a back mold M21 located on the back side of the lens portion 10 to mold the outer frame portion 20 integrated with the lens portion 10.

[0054] As can be understood from the previous description, in the second molding step, regarding the mold corresponding to the front side, the front mold M11 used in the first molding step is used, and the mold M2 is formed by the front mold M11 and the back mold M21.

[0055] Then, when the front mold M11 and back mold M21, which hold the lens portion 10, are brought together, a space SP2 corresponding to the shape of the outer frame portion 20 is formed inside the molding mold M2. A colored resin (in this example, black resin is used) which will be the material for the outer frame portion 20 is poured into this space SP2, and once the resin has hardened, the front mold M11 and back mold M21 are removed and taken out of the molding mold M2 to obtain the lens member 1.

[0056] As shown in Figure 7, the back surface of the M21 is such that it does not come into contact with the inner region 11 of the lens portion 10, and the surface corresponding to the inner region 11 of the lens portion 10 is spaced apart from the inner region 11.

[0057] In this way, the back-side type M21 does not come into contact with the inner region 11 of the lens portion 10, thereby preventing scratches and other damage to the back surface of the lens portion 10.

[0058] Figure 8 is a magnified view of a part of Figure 7, specifically the part indicated by the circled MB2. As shown in Figure 8, the back surface type M21 abuts against the intermediate region 12 of the lens portion 10 and has a contact surface M21A that determines the tip position 21A (see Figure 4) of the integrated portion 21 of the outer frame portion 20.

[0059] Furthermore, this contact surface M21A abuts the intermediate region 12 at the portion with a second thickness T2, which is formed in the portion with a second width W2, and is formed as a surface that gradually increases in distance from the intermediate region 12 toward the inner region 11 side of the intermediate region 12.

[0060] By forming the surface in such a way that the distance from the intermediate region 12 gradually increases, the contact area with the intermediate region 12 becomes smaller. Therefore, when the surface mold M11 and the back mold M21 are brought together with the same pressing force, the contact surface M21A is firmly pressed against the intermediate region 12, thereby suppressing leakage of the colored resin to the back side of the intermediate region 12.

[0061] Furthermore, by reducing the contact area with the intermediate region 12, the area of ​​the intermediate region 12 that may be damaged can be suppressed, resulting in a better appearance.

[0062] Next, we will describe an example of a test conducted to actually confirm the muscle inhibitory effect. Figure 9 shows a lens member with a conventional structure, and corresponds to Figure 4.

[0063] As shown in Figure 9, the conventional structure, like the first embodiment, includes an inner region B11, an intermediate region B12 provided along the outer circumference of the inner region B11 and defining the tip position B21A of the integrated portion B21 of the outer frame 20, and an outer region B13 provided along the outer circumference of the intermediate region B12 and overlapping with the integrated portion B21.

[0064] On the other hand, in the conventional structure, the intermediate region B12 has a second thickness T2 almost entirely, and changes to a first thickness T1 near the inner region B11.

[0065] Figure 10 shows the surface side of the lens member 1 of the first embodiment according to the present invention and the lens member of the conventional structure shown in Figure 9, with the conventional lens member shown in Figure 9 on the left and the lens member 1 of the first embodiment on the right.

[0066] As can be seen in Figure 10, in conventional lens members, a streak LN is visible between the inner region B11 and the intermediate region B12. However, in the lens member 1 of the first embodiment, the streak LN between the inner region 11 and the intermediate region 12 is almost invisible, demonstrating significant improvement.

[0067] Thus, with the lens member 1 of the vehicle lamp according to the first embodiment, streaks (shadows) caused by steps or other differences between the inner region 11 and the intermediate region 12 can be suppressed, resulting in a visually appealing lens member 1.

[0068] <<Second Embodiment>> Next, with reference to Figure 11, the lens member 1 of the vehicle lamp according to the second embodiment of the present invention and its manufacturing method will be described.

[0069] Figure 11 is a diagram illustrating the lens member 1 of a vehicle lamp according to a second embodiment of the present invention, and corresponds to Figure 4.

[0070] Since the basic configuration of the lens member 1 of the vehicle lamp in the second embodiment is the same as that of the lens member 1 of the vehicle lamp in the first embodiment, the following description will mainly focus on the differences from the first embodiment, and explanations of the points that are the same as in the first embodiment may be omitted.

[0071] As shown in Figure 11, the outer region 13 of the lens portion 10 in the second embodiment has a thickness increasing portion 131 that increases in thickness toward the intermediate region 12, from a third thickness T3 that is thinner than the second thickness T2 to a second thickness T2.

[0072] In the first embodiment, as shown in Figure 4, the boundary between the outer region 13 and the intermediate region 12 rises at almost a right angle. Therefore, when the surface type M11 and the back type M21 are brought together and the contact surface M21A presses against the second thickness T2 portion of the intermediate region 12, stress may concentrate, potentially causing chipping or other damage.

[0073] On the other hand, in the second embodiment, the intermediate region 12 has a flared shape centered on the second thickness T2 portion, which allows for the relaxation of the stress described above and thus suppresses the occurrence of chipping and other damage.

[0074] The manufacturing method of the second embodiment differs from that of the first embodiment in that the outer space SP13 (see Figure 6) that forms the outer region 13 has a spatial shape corresponding to the thickness increase portion 131.

[0075] In other words, the only difference in the manufacturing method of the second embodiment is that the outer space SP13 has a width-increasing space that widens toward the intermediate space SP12, from a third width narrower than the second width W2 to the second width W2.

[0076] Although the present invention has been described above based on specific embodiments, the present invention is not limited to the above embodiments.

[0077] In the above embodiment, an example of forming the lens member 1 using two-color molding was described as an example of multi-color molding, but the number of molding steps may be increased as needed, such as to use three-color molding.

[0078] Thus, the present invention also includes modifications and improvements to the above embodiments, which will be clear to those skilled in the art from the claims.

[0079] Furthermore, the following additional notes are disclosed regarding the above embodiments. [Addendum 1] A lens member for a vehicle lamp, wherein the lens member comprises a light-transmitting lens portion and an outer frame portion having an integrated portion that overlaps along the outer circumference of the lens portion and integrates with the lens portion, wherein the lens portion comprises an inner region of a first thickness, an intermediate region provided along the outer circumference of the inner region and defining the tip position of the integrated portion, and an outer region provided along the outer circumference of the intermediate region and overlapping with the integrated portion, wherein the intermediate region gradually thins toward the inner region, from a second thickness on the tip position side which is thicker than the first thickness, to the first thickness. [Addendum 2] The lens member according to Addendum 1, wherein the intermediate region has a first length from the second thickness to the first thickness, and the first length is 10 times or more the difference between the second thickness and the first thickness. [Note 3] The lens member according to Note 1 or Note 2, characterized in that the second thickness is such that the difference between the second thickness and the first thickness is 1 mm or less, and the first length is 10 mm or more and 20 mm or less. [Note 4] The lens member according to any one of Notes 1 to 3, characterized in that the integrated portion is located in the outer region on the back side of the lens portion, and the portion of the second thickness protrudes on the back side of the lens portion to define the tip position. [Note 5] The lens member according to any one of Notes 1 to 4, characterized in that the outer region has a thickness increasing portion toward the intermediate region, where the thickness increases from a third thickness that is thinner than the second thickness to the second thickness.[Note 6] A manufacturing method for producing a lens member of a vehicle lamp comprising a lens portion and an outer frame portion by multi-color molding, comprising: a first molding step of molding the light-transmitting lens portion; and a second molding step of molding the outer frame portion having an integrated portion that overlaps along the outer circumference of the lens portion and integrates with the lens portion, wherein the first molding step is a step of molding the lens portion by supplying a light-transmitting resin into a mold, and the mold comprises: an inner space having a first width corresponding to the inner region of the lens portion having a first thickness; an intermediate space provided along the outer circumference of the inner space and corresponding to an intermediate region of the lens portion that defines the tip position of the integrated portion; and an outer space provided along the outer circumference of the intermediate space and corresponding to the outer region of the lens portion that overlaps with the integrated portion, wherein the intermediate space is a space in which the width gradually narrows toward the inner space, from a second width on the side corresponding to the tip position side which is wider than the first width, to the first width. [Note 7] The manufacturing method according to Note 6, characterized in that the intermediate space has a first length from the second width to the first width, and the first length is 10 times or more the difference between the second width and the first width. [Note 8] The manufacturing method according to Note 7, characterized in that the second width is a width such that the difference between the second width and the first width is 1 mm or less, and the first length is 10 mm or more and 20 mm or less. [Note 9] The manufacturing method according to any one of Notes 6 to 8, characterized in that the integrated portion is located in the outer region on the back surface side of the lens portion, and the portion of the second width forms a protruding space that protrudes in a direction corresponding to the back surface side of the lens portion such that it forms a protrusion that defines the tip position of the intermediate region.[Note 10] The manufacturing method according to Note 9, wherein the second molding step is a step of supplying resin into a mold including a back mold located on the back side of the lens portion to form the outer frame portion integrated with the lens portion, the back mold has a contact surface that abuts against the intermediate region of the lens portion and determines the tip position, and the contact surface abuts against the intermediate region on the side of the second thickness portion of the intermediate region formed in the second width portion, and is formed on a surface that gradually increases in distance from the intermediate region toward the inner region side of the intermediate region. [Note 11] The manufacturing method according to any one of Notes 6 to 10, wherein the outer space has a width-increasing space toward the intermediate space, in which the width increases from a third width narrower than the second width to the second width.

Claims

1. A lens member for a vehicle light fixture, wherein the lens member comprises a light-transmitting lens portion and an outer frame portion having an integrated portion that overlaps along the outer circumference of the lens portion and integrates with the lens portion, wherein the lens portion comprises an inner region of a first thickness, an intermediate region provided along the outer circumference of the inner region and defining the tip position of the integrated portion, and an outer region provided along the outer circumference of the intermediate region and overlapping with the integrated portion, wherein the intermediate region gradually thins toward the inner region, from a second thickness on the tip position side which is thicker than the first thickness, to the first thickness.

2. The lens member according to claim 1, characterized in that the intermediate region has a first length from the second thickness to the first thickness, and the first length is 10 times or more the difference between the second thickness and the first thickness.

3. The lens member according to claim 2, characterized in that the second thickness is such that the difference between the second thickness and the first thickness is 1 mm or less, and the first length is 10 mm or more and 20 mm or less.

4. The lens member according to any one of claims 1 to 3, characterized in that the integrated portion is located in the outer region on the back side of the lens portion, and the portion of the second thickness protrudes on the back side of the lens portion to define the tip position.

5. The lens member according to any one of claims 1 to 3, characterized in that the outer region has a thickness increasing portion toward the intermediate region, where the thickness increases from a third thickness that is thinner than the second thickness to the second thickness.

6. A manufacturing method for producing a lens member of a vehicle lamp comprising a lens portion and an outer frame portion by multi-color molding, comprising: a first molding step of molding the light-transmitting lens portion; and a second molding step of molding the outer frame portion having an integrated portion that overlaps along the outer circumference of the lens portion and integrates with the lens portion, wherein the first molding step is a step of molding the lens portion by supplying a light-transmitting resin into a mold, and the mold comprises: an inner space having a first width corresponding to the inner region of the lens portion having a first thickness; an intermediate space provided along the outer circumference of the inner space and corresponding to an intermediate region of the lens portion that defines the tip position of the integrated portion; and an outer space provided along the outer circumference of the intermediate space and corresponding to an outer region of the lens portion that overlaps with the integrated portion, wherein the intermediate space is a space in which the width gradually narrows toward the inner space, from a second width on the side corresponding to the tip position side which is wider than the first width, to the first width.

7. The manufacturing method according to claim 6, characterized in that the intermediate space has a first length from the second width to the first width, and the first length is 10 times or more the difference between the second width and the first width.

8. The manufacturing method according to claim 7, characterized in that the second width is such that the difference between the second width and the first width is 1 mm or less, and the first length is 10 mm or more and 20 mm or less.

9. The manufacturing method according to any one of claims 6 to 8, characterized in that the integrated portion is located in the outer region on the back side of the lens portion, and the second width portion forms a protruding space that protrudes in a direction corresponding to the back side of the lens portion such that it forms a protrusion that defines the tip position of the intermediate region.

10. The manufacturing method according to claim 9, wherein the second molding step is a step of supplying resin into a mold including a back mold located on the back side of the lens portion to form the outer frame portion integrated with the lens portion, the back mold has a contact surface that abuts against the intermediate region of the lens portion and determines the tip position, and the contact surface is formed on a surface that abuts against the intermediate region on the side of the second thickness portion of the intermediate region formed in the second width portion, and gradually increases in distance from the intermediate region toward the inner region side of the intermediate region.

11. The manufacturing method according to any one of claims 6 to 8, characterized in that the outer space has a width-increasing space that widens toward the intermediate space from a third width narrower than the second width to the second width.

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