TWI691397B - Fresnel lens injection molding mold device using rapid cooling and hot mold core - Google Patents

Abstract

A manufacturing method of a Fresnel lens using rapid cooling and rapid heating of the mold core includes: an injection step, a mold core rapid heating step, a transfer step, and a rapid cooling molding step. The injection step includes injecting a liquid thermoplastic plastic material into at least one cavity of a Fresnel lens injection molding mold device. The rapid heating process of the mold core includes injecting a high-temperature fluid into the mold core waterway in at least one mold core of at least one pair of mold cores to quickly heat the mold core to a temperature at which the thermoplastic plastic material can flow. In the rapid temperature-lowering molding step, a low-temperature fluid is injected into the mold core waterway of the mold core to rapidly cool the liquid thermoplastic material in the mold cavity and cool and solidify it into a Fresnel lens. Through the mold water channel, the injection molding mold device can be uniformly and rapidly heated and cooled to avoid local cooling and solidification of the plastic material, thereby improving the optical quality of the Fresnel lens.

Description

Fresnel lens injection molding mold device using rapid cooling and hot mold core

The invention relates to a method for manufacturing a lens, in particular to a method for manufacturing a Fresnel lens using rapid cooling and hot mold cores and a Fresnel lens injection molding die device. This manufacturing method allows the plastic material to be fully filled into the cavity of the mold through the quenching and heating process of the thermoplastic plastic material, so that the manufactured Fresnel lens is generated on the tip of the sawtooth portion and the groove The structure is sharp enough, and the surface of the Fresnel lens has a specular effect, thereby improving the optical quality of the Fresnel lens.

Fresnel lens is also called screw lens. Its optical characteristic is characterized by short focal length, and it is more material saving and lighter than ordinary lens. Compared with earlier lens designs, the Fresnel lens is thinner, so it can transmit more light. Therefore, after the light source is refracted through the Fresnel lens, it can more effectively emit light to the distance.

Fresnel lenses are widely used in light tower projection navigation lights, projection projector lenses, rear projection display screens, and car headlights. They can be described as the most widely used lenses.

Most of today's optical lenses are made with injection molding methods and molds. Traditional Fresnel lenses are also mainly produced by this method. In general, Fresnel lenses are formed by molding thermoplastics through an injection molding machine . However, in the existing Fresnel lens mold, due to the slow temperature rise of the mold and the uneven temperature of various parts of the mold, the speed of the thermoplastic plastic flowing in the cavity of the mold is different, so the molding cycle is too long, which leads to injection molding. In the process, it is easy to produce defect flow marks and gas lines on the surface of the Fresnel lens, which ultimately makes the surface of the Fresnel lens unable to achieve the effect of sufficiently high-gloss mirror surface. In addition, due to the uneven temperature of various parts of the mold during processing, the plastic material with a lower temperature is cooled and formed first, resulting in short shot defects that are insufficiently filled in the sharp parts of the Fresnel lens. Defective Fresnel lenses are also accompanied by stress build-up, which affects optical imaging and seriously affects the quality of Fresnel lenses.

Please refer to FIG. 18, the above-mentioned conventional Fresnel lens 90 with short-shot defects has a magnification of 15 times optical magnification due to insufficient filling of the plastic material at the tip 91 of the saw tooth portion of the cross section and the groove 92 between adjacent saw tooth portions The magnification of the electron microscope has shown a blunt rounded corner, rather than the ideal sharp shape.

Up to now, the industry has not produced any serrations and grooves with a sharp Fresnel lens under an electron microscope with an optical magnification of more than 15 times through any processing method.

In view of the existing injection molding machine and manufacturing method for manufacturing Fresnel lenses, the injection molding process is caused by insufficient filling of the mold cavity due to uneven cooling and heating of various parts of the mold, resulting in sharpness of the serrated part of the finished Fresnel lens The shortcomings affect the shortcomings such as optical quality, improve their shortcomings and deficiencies, and then create a method of manufacturing a Fresnel lens using a rapid cooling and hot mold core and a Fresnel lens injection molding die device.

The main object of the present invention is to provide a manufacturing method of a Fresnel lens using rapid cooling and rapid heating mold cores and a Fresnel lens injection molding die device. This manufacturing method allows the plastic material to be fully filled into the cavity of the mold through the quenching and heating process of the thermoplastic plastic material, so that the manufactured Fresnel lens is generated on the tip of the sawtooth portion and the groove Sharp enough The structure of the Fresnel lens makes the surface of the Fresnel lens have a specular effect, thereby improving the optical quality of the Fresnel lens.

In order to achieve the above purpose, the manufacturing method of Fresnel lens using rapid cooling and hot mold core includes: an injection step, injecting liquid thermoplastic plastic material into a mold cavity in a Fresnel lens injection molding mold device; a mold core is fast In the heating step, the Fresnel lens is injected into the mold core waterway in at least one of the mold cores in at least one pair of mold cores in the molding mold device to inject high-temperature fluid to quickly heat the mold core until the thermoplastic plastic material can flow Temperature; a transfer step, using the pair of mold cores to pressurize the liquid thermoplastic plastic material in the mold cavity to produce a Fresnel lens structure in the thermoplastic plastic material; a rapid cooling molding step, the original high temperature is injected The mold core water path of the fluid mold core is changed to inject a low-temperature fluid to quickly cool the liquid thermoplastic material in the mold cavity and cool and solidify it into a Fresnel lens.

The high-temperature fluid uses the above-mentioned technical means. The method of manufacturing the Fresnel lens using rapid cooling and rapid heating mold core adopts the first mold core water channel and the second mold core water channel to supply hot steam, hot water or cold water into it, so as to quickly And uniformly heat or cool the female mold core and the male mold core, which makes the temperature of each part of the plastic material in the mold cavity rise and fall quickly, uniformly and uniformly, to avoid the surface of the Fresnel lens caused by the injection molding process taking too long Defect flow marks, gas lines, in addition, uniform temperature control can avoid the short-shot phenomenon caused by the cooling and solidification of the thermoplastic material part first, so it can increase the sharpness of the sharp parts of the Fresnel lens, thereby enhancing the optical of the Fresnel lens quality.

The aforementioned mold core is a female mold core and a male mold core, and the mold core waterway is formed in the female mold core.

The aforementioned mold core is a female mold core and a male mold core, and the mold core waterway is formed in the male mold core.

The pair of mold cores is a female mold core and a male mold core, and the female mold core and the male mold core each have a mold core waterway.

In the aforementioned mold core heating step, high-temperature fluid is injected into both mold core water channels at the same time.

In the aforementioned rapid cooling step, a low-temperature fluid is simultaneously injected into the two mold core waterways.

In the rapid heating step of the mold core, a high temperature steam is input to the mold core water channel through a quenching and rapid heating mold temperature controller to perform rapid heating; in the rapid cooling forming step, the rapid cooling mold temperature control machine is adopted Let's input low-temperature water to the mold core waterway for rapid cooling.

Another object of the present invention is to provide a Fresnel lens injection molding die device suitable for the foregoing manufacturing method, which includes: a mother die on which at least one first assembly groove is formed, and a surface formed on one side of the mother die A first mold cavity communicating with the first assembling groove; a male mold, which is connected to the female mold, can move relative to the female mold to abut or move away from the female mold, and at least one corresponding to the first mold is formed on the male mold An assembly groove is aligned with the second assembly groove, and a second mold cavity communicating with the second assembly groove is formed on one surface of the male mold. The second mold cavity and the first mold cavity together form a mold cavity ; At least one female mold core, respectively set in the corresponding first assembly groove, a first mold core waterway is formed in the female mold core; and at least one male mold core, respectively set in the corresponding second assembly groove And match with the female mold kernel.

A second moldin waterway is formed in the aforementioned male moldin.

The first assembly groove is plural, and the female mold core is plural; the first mold cavity has a first main plastic flow channel and plural first branch plastic flow channels, the plural first branch plastic flow The channels extend outward from the first main plastic flow channel and communicate with the plurality of first assembling grooves, respectively.

There are a plurality of second assembly grooves and a plurality of male mold cores; the second mold cavity has a second main plastic flow channel and a plurality of second branch plastic flow channels, the second main plastic flow channel corresponds to the first main For the plastic flow channels, the plurality of second branched plastic flow channels respectively correspond to the plurality of first branched plastic flow channels, and extend outward from the second main plastic flow channel and communicate with the plurality of second assembly grooves, respectively.

The first mold core water channel of the aforementioned female mold core is quadrangular, and the two opposite vertices of the first mold core water channel are two first connecting points. A first sealing gasket provided on the female mold core penetrates to form two The first yielding through holes are connected to the two first communicating points respectively.

The second mold core water channel of the aforementioned male mold core is quadrangular, and two opposite vertices of the second mold core water channel are two second connecting points, and a second seal gasket provided on the male mold core penetrates to form a second Two yielding through holes, the two second yielding through holes are respectively connected to the two second communicating points.

The aforementioned Fresnel lens injection molding mold device further includes a fixed substrate and a movable substrate, the fixed substrate and the mother mold are fixed to each other, and at least one first mold core pipe group is provided on the fixed substrate, each first mold core The pipeline group has a first inflow tube and a first outflow tube to connect to the two first yielding through holes corresponding to the female mold core respectively; the movable substrate and the male mold are fixed to each other, and at least one is provided on the movable substrate The second mold core pipeline group, each second mold core pipeline group has a second inflow pipe and a second outflow pipe to connect to the two second concession through holes of the corresponding male mold core respectively.

The aforementioned female mold has a female mold backing block and a female mold outer frame, the at least one first assembly groove and the first mold cavity are formed in the female mold backing block, the female mold outer frame is hollow and sleeved on The master mold liner.

The male mold has a male mold liner and a male mold frame, the at least one second assembly groove and the second cavity are formed in the male mold liner, the male mold frame is hollow and sleeved The male mold liner.

Another object of the present invention is to provide a Fresnel lens manufactured by the foregoing manufacturing method, which includes: a lens body and a plurality of concentric annular ribs formed on the lens body and arranged in a concentric circle , On the side section through the center axis of the Fresnel lens, the complex concentric annular ribs respectively have a sawtooth section, and the complex sawtooth section is bilaterally symmetrical with respect to the center axis; Under the observation of the magnification microscope, the tips of the serrated cross-sections of the concentric annular ribs appear sharp without rounded corners.

There is a zigzag groove cross-section between any two adjacent zigzag cross-sections. Under the observation of a microscope with a magnification of up to 150, the bottom of the zigzag groove cross-section is sharp without rounded corners.

1: Fresnel lens injection molding die device

2: Rapid cooling and hot mold temperature controller

3: plastic injection molding machine

10: Female mold

11: Master frame

13: Master block

130: the first assembly slot

135: The first mold waterway

1350: First meeting point

1351: The first main branch path

1352: The first secondary branch path

136: The first main plastic flow channel

137: The first branch plastic flow channel

20: Male mold

21: male frame

23: Male mold liner

230: second assembly slot

235: Second mold waterway

2350: second meeting point

2351: Second main branch path

2352: Second secondary branch path

30: Female mold kernel

300: The first Fresnel structure transfer surface

301: First gasket

31, 32: the first concession via

35: The First Mo Ren Waterway

350: first connection point

40: male model

400: The second Fresnel structure transfer surface

401: second gasket

41, 42: second concession via

45: Second Moin Waterway

450: second connection point

50: fixed substrate

51: The first inflow pipe

52: The first outflow tube

60: movable substrate

61: Second inflow pipe

62: Second outflow tube

80: Fresnel lens

80a: Fresnel lens plastic department

81: Sawtooth bump cross section

811: tip

82: Sawtooth groove cross section

821: bottom

C36: Main plastic runner

C37: Branch plastic runner

90: Traditional Fresnel lens

91: tip

92: Groove

Fig. 1 is a perspective view of the present invention.

Figure 2 is a cross-sectional view of the present invention.

Figure 3 is the most exploded perspective view of the female mold, female mold core, male mold and male mold core of the present invention.

Fig. 4 is an exploded perspective view of the master block and master core of the present invention.

Fig. 5 is a three-dimensional exploded view of the female mold core of the present invention.

Fig. 6 is an exploded perspective view of the male mold backing block and male mold core of the present invention.

Figure 7 is a three-dimensional exploded view of the male mold kernel of the present invention.

Fig. 8 is a perspective external view of the plastic plastic in the cavity of the present invention.

Fig. 9 is a schematic plan view of the master die pad of the present invention.

Fig. 10 is a schematic plan view of the male die pad of the present invention.

Fig. 11 is a schematic plan view of the female mold core of the present invention.

Fig. 12 is a schematic plan view of the male mold core and its internal mold waterway.

FIG. 13 is a perspective schematic view of the mold waterway and mold core pipeline assembly of the present invention along the overlapping direction of the female mold and the male mold.

Fig. 14 is a cross-sectional view of the Fresnel lens of the present invention along the central axis.

Fig. 15 is an enlarged schematic cross-sectional view of a Fresnel lens of the present invention under an electron microscope with an optical magnification of 150 times.

Fig. 16 is a system block diagram of a Fresnel lens injection molding mold device, a rapid cooling and rapid mold temperature controller and a plastic injection molding machine of the present invention.

FIG. 17 is a flow chart of the steps of the method for manufacturing a Fresnel lens using rapid cooling and rapid thermal mold cores according to the present invention.

Figure 18 is an enlarged schematic cross-sectional view of a traditional Fresnel lens under an electron microscope with 15x optical magnification.

Please refer to FIG. 1 to FIG. 3 and FIG. 16, the Fresnel lens injection molding mold device 1 of the present invention can be connected to a quenching and heating mold temperature controller 2 and a plastic injection molding machine 3, and includes: a female mold 10, a male The mold 20, at least one female mold core 30, at least one male mold core 40, a fixed substrate 50 and a movable substrate 60.

Please refer to FIGS. 4 and 9, at least one first assembling groove 130 is formed on the mother mold 10, and a first mold water channel 135 is formed in the mother mold 10 for the quenching and heating mold Hot steam, hot water or cold water injected by the temperature controller 2 is injected therein, so that the mother mold 10 is heated or cooled quickly and uniformly. The first mold water channel 135 may be quadrangular, spiral, U-shaped or any shape that can be uniformly distributed in the mother mold 10. The above-mentioned high-temperature hot steam may be a high temperature of 140 degrees Celsius to 160 degrees Celsius. At this temperature, good fluidity of general thermoplastic plastic materials can be maintained, and the temperature of the hot steam can be increased depending on the situation; in addition, cold water can be 80 degrees Celsius to 90 degrees Celsius At this temperature, general thermoplastic plastic materials can be cooled and solidified, and the temperature of the cold water can be increased or decreased according to the situation. A first mold cavity communicating with the first assembly groove 130 is formed on one surface of the female mold 10 for the plastic injection molding machine 3 to inject thermoplastic plastic material therein. In addition, the temperature (also called the material temperature) of the thermoplastic plastic material of the plastic injection molding machine 3 at the time of injection is generally between 200 degrees Celsius and 260 degrees Celsius.

In a preferred embodiment, the female mold 10 has a female mold pad 13 and a female mold frame 11, the at least one first assembly groove 130, the first mold water channel 135 and the first mold cavity are formed in In the female mold pad 13, the female mold outer frame 11 is hollow and is sleeved on the female mold pad 13. The two opposite vertices of the first mold water channel 135 are two first confluence points 1350. A first main branch path 1351 is formed on each first confluence point 1350. The first main branch path 1351 extends to the mother die pad 13 outer. In addition, two first sub-branched passages 1352 are formed on each first confluence point 1350, and the two first sub-branched passages 1352 extend beyond the mother die pad 13. The first main branch path 1351 can be connected to the pipeline from the quenching and heating mold temperature control machine 2 for injecting hot steam, hot water or cold water into the master mold liner 13. The first sub-branched passages 1352 can be screwed and sealed without being connected to external pipelines, or can be connected to the mold temperature controller 2 from the rapid cooling and rapid heating in other conditions.

Referring to FIGS. 6, 10 and 13, the male mold 20 and the female mold 10 are connected to each other, and can move relative to the female mold 10 to abut against or move away from the female mold 10. A second mold water path 235 is formed in the male mold 20 for the hot steam injected by the quenching and hot mold temperature controller 2, Hot water or cold water is injected therein, so that the male mold 20 is heated or cooled quickly and uniformly. The second mold water channel 235 can be quadrangular, spiral, U-shaped or any shape that can be uniformly distributed in the male mold 20. The second mold water channel 235 and the first mold water channel 135 may cross each other, as shown in FIG. 13. The male mold 20 is formed with at least one second assembling groove 230 aligned with the corresponding first assembling groove 130, and a second mold cavity communicating with the second assembling groove 230 is formed on one surface of the male mold 20 For the plastic injection molding machine 3 to inject thermoplastic plastic material into it. The second mold cavity and the first mold cavity together form a mold cavity.

In a preferred embodiment, the male mold 20 has a male mold pad 23 and a male mold outer frame 21, the at least one second assembly groove 230, the second mold water channel 235 and the second mold cavity are formed in In the male mold pad 23, the male mold outer frame 21 is hollow and is sleeved on the male mold pad 23. The two opposite vertices of the second mold water channel 235 are two second confluence points 2350, and a second main branch path 2351 is formed on each second confluence point 2350. The second main branch path 2351 extends to the male mold pad 23 outer. In addition, two second sub-branched passages 2352 are formed on each second confluence point 2350 of the second mold water passage 235, and the two second sub-branched passages 2352 extend beyond the male mold pad 23. The second main branch passage 2351 may be connected to the pipeline from the quenching and heating mold temperature control machine 2 for supplying hot steam, hot water or cold water into the male mold liner 23. The second secondary branch passages 2352 can be screwed and sealed without connecting external pipelines, or can be connected to the mold temperature controller 2 from the quenching and heating mold under other conditions.

Please refer to FIGS. 4, 5 and 11, the female mold core 30 is disposed in the corresponding first assembly groove 130. A first mold core water passage 35 is formed inside the female mold core 30 for hot steam, hot water or cold water injected by the quenching and rapid mold temperature controller 2 to quickly and uniformly heat or cool the female mold Mo Ren 30. The first mold core waterway 35 may be quadrangular, spiral, U-shaped or any shape that can be evenly distributed in the female mold core 30. The two opposite vertices of the first mold core waterway 35 are two first communication points 350, which pass through a first sealing gasket 301 provided on the female mold core 30 Two first yielding through holes 31 and 32 are formed through the hole, and the two first yielding through holes 31 and 32 are respectively connected to the two first communication points 350. In addition, a first Fresnel structure transfer surface 300 is formed on an inner surface of the female mold core 30, which may be aspherical. In addition, two bolts may be provided on the female mold core 30 to further fix the first sealing gasket 301 on the female mold core 30.

Please refer to FIGS. 6, 7 and 12, the male mold core 40 is disposed in the corresponding second assembly groove 230 and matches the female mold core 30. A second mold core water passage 45 is formed inside the male mold core 40 for hot steam, hot water or cold water injected by the quenching and rapid mold temperature controller 2 to quickly and uniformly heat or cool the male mold core Mo Ren 40. The second mold core waterway 45 may be quadrangular, spiral, U-shaped or any shape that can be uniformly distributed in the male mold core 40. The two opposite vertices of the second mold core waterway 45 of the male mold core 40 are two second communication points 450, and a second sealing gasket 401 provided on the male mold core 40 penetrates therethrough to form two second concessions The holes 41 and 42 and the two second through holes 41 and 42 are respectively connected to the two second communication points 450. In addition, a second Fresnel structure transfer surface 400 is formed on an inner surface of the male mold core 40. The first Fresnel structure transfer surface 300 and the second Fresnel structure transfer surface 400 are respectively imprinted on the surface of the thermoplastic plastic material in the mold cavity to manufacture a Fresnel lens. In addition, two bolts may be provided on the male mold core 40 to further fix the second sealing gasket 401 on the male mold core 40.

Please refer to FIGS. 4, 6 and 8. In the preferred embodiment of the present invention, the first assembly groove 130 is plural, and the female mold core 30 is plural; the first mold cavity has a first main plastic flow channel 136 And a plurality of first branched plastic flow channels 137, the plurality of first branched plastic flow channels 137 extend outward from the first main plastic flow channel 136 and communicate with the plurality of first assembly grooves 130, respectively. In addition, there are a plurality of second assembly grooves 230 and a plurality of male mold cores 40; the second mold cavity has a second main plastic flow channel 236 and a plurality of second branch plastic flow channels 237, the second main plastic flow channel 236 corresponds to the first main plastic flow channel 136, the plurality of second branch plastic flow channels 237 respectively correspond to the plurality of first branch plastic flow channels 137, and extend outward from the second main plastic flow channel 236 and divide Do not communicate with the plurality of second assembly grooves 230. Through the configuration of the complex female mold core 30 and the male mold core 40, the Fresnel lens injection molding die device 1 can produce several Fresnel lenses in a single processing procedure. The plastic distribution in the mold cavity is as shown in Fig. 8, showing a main plastic flow channel part C36, a plurality of branch plastic flow channel parts C37 connected to the main plastic flow channel part C36, and a plurality of branch plastic flow channel parts C37 respectively Fresnel lens plastic part 80a. Hot water vapor, hot water or cold water is injected through the first mold water channel 135 and the second mold water channel 235 to uniformly quench and heat the mother mold 10 and the male mold 20, so that the main plastic flow channel portion C36 and the branch plastic flow The temperature of the channel portion C37 and the Fresnel lens plastic portion 80a rises and falls uniformly, and there is no problem that the local plastic material temperature is too low and the first curing causes the Fresnel lens to be poorly formed and reduce its optical quality.

The fixed substrate 50 and the mother mold 10 are fixed to each other, and at least one first mold core pipe group is provided on the fixed base plate 50, and each first mold core pipe group has a first inflow pipe 51 and a first outflow pipe 52 To connect to the two first yielding through holes 31, 32 corresponding to the female mold core 30, respectively. The first inflow pipe 51 and the first outflow pipe 52 can be connected to the quenching and heating mold temperature controller 2, thereby injecting hot steam, hot water or cold water into the female mold core 30.

The movable substrate 60 and the male mold 20 are fixed to each other. At least one second mold core pipe group is provided on the movable base plate 60, and each second mold core pipe group has a second inflow pipe 61 and a second outflow The tube 62 is respectively connected to the two second yielding through holes 41 and 42 corresponding to the male mold core 40. The second inflow pipe 61 and the second outflow pipe 62 can be connected to the rapid cooling and rapid heating mold temperature controller 2, thereby injecting hot steam, hot water or cold water into the male mold core 40.

Referring to FIGS. 1, 16, and 17, the present invention uses the Fresnel lens injection molding die device 1 to manufacture a Fresnel lens using rapid cooling and rapid heating mold core, including: an injection step S01, a mold core rapid heating step S02, a transfer step S03 and a rapid cooling forming step S04.

The injection step S01 of the high-temperature fluid includes injecting a liquid thermoplastic plastic material into a cavity of the Fresnel lens injection molding mold device 1. In the injection step S01, thermoplastic resin is injected into the Fresnel lens injection molding device 1 through the plastic injection molding machine 3 described above.

The mold core rapid heating step S02 includes injecting a high-temperature fluid into the mold core waterway in at least one mold core of at least one pair of mold cores in the Fresnel lens injection molding mold device 1 to quickly heat the mold core to The temperature at which thermoplastic materials can flow. Among them, the pair of mold kernels are the above-mentioned female mold kernel 30 and male mold kernel 40. In a preferred embodiment, the female mold core 30 in the pair of mold cores has a first mold core water passage 35 for injecting high-temperature fluid. In another preferred embodiment, the male mold core 40 of the pair of mold cores has a second mold core water passage 45 for injecting high-temperature fluid. In yet another preferred embodiment, the female mold core 30 of the pair of mold cores has a first mold core water channel 35 and the male mold core 40 has a second mold core water channel 45 for respectively injecting high-temperature fluids. In the mold core rapid heating step S02, high-temperature steam is input to the mold core water channel through the quenching and rapid heating mold temperature controller 2 to perform rapid heating.

The transferring step S03 includes pressurizing the liquid thermoplastic plastic material in the mold cavity with at least one pair of mold cores to generate a Fresnel lens structure on the thermoplastic plastic material.

The rapid temperature-lowering molding step S04 includes changing the mold core waterway of the mold core originally injected with the high-temperature fluid to inject low-temperature fluid to quickly cool the liquid thermoplastic material in the mold cavity and solidify it into a Fresnel lens. In the rapid temperature-lowering molding step S04, low-temperature water is input to the mold core water channel through the quenching and rapid-heating mold temperature controller 2 to perform quenching.

Referring to FIGS. 14 and 15, the Fresnel lens 80 manufactured by the foregoing manufacturing method according to the present invention includes: a lens body and a plurality of concentric annular ribs, the plurality of concentric annular ribs are formed on the lens body and Arranged in a concentric manner, on the side section passing through the center axis of the Fresnel lens, the complex concentric ring-shaped ribs respectively have a zigzag bump section 81, the complex number The zigzag bump cross-section 81 is distributed symmetrically with respect to the central axis, and there is a zigzag groove cross-section 82 between any two adjacent zigzag bump cross-sections 81.

Under the observation of a microscope with a magnification of up to 150, the tip 811 of the serrated bump cross-section 81 of each concentric annular rib is sharp and not rounded, and the bottom 821 of each serrated groove cross-section 82 is sharp and not Rounded corners.

With the above technical means, the Fresnel lens injection molding die device 1 and its manufacturing method of the present invention use the first mold core water channel 35 and the second mold core water channel 45 to supply hot steam, hot water or cold water into it, thereby Quickly and uniformly heat or cool the female mold 10 and the male mold 20, which makes the temperature of each part of the plastic material in the mold cavity rise and fall quickly, uniformly and uniformly, to avoid the injection molding process taking too long and causing the surface of the Fresnel lens Defect flow marks and gas lines are generated. In addition, the uniform temperature control can avoid the short-shot phenomenon caused by the cooling and solidification of the thermoplastic material part first, so it can increase the sharpness of the sharp parts of the Fresnel lens, thereby enhancing the Fresnel lens. The optical quality is shown in Figure 15.

1: Fresnel lens injection molding die device

10: Female mold

11: Master frame

20: Male mold

21: male frame

50: fixed substrate

51: The first inflow pipe

52: The first outflow tube

60: movable substrate

61: Second inflow pipe

62: Second outflow tube

Claims (7)

A Fresnel lens injection molding mold device includes: a female mold on which at least one first assembly groove is formed, and a first mold cavity communicating with the first assembly groove is formed on one surface of the female mold; A male mold, which is connected to the female mold, can move relative to the female mold to abut or move away from the female mold, and at least one second assembly groove is formed on the male mold to match the corresponding first assembly groove, A second mold cavity communicating with the second assembly groove is formed on one surface of the male mold, and the second mold cavity and the first mold cavity together form a mold cavity; at least one female mold core is respectively disposed on the corresponding In the first assembling groove, a first mold core water channel is formed in the female mold core, the first mold core water channel is quadrangular, and two opposite vertices of the first mold core water channel are two first connecting points. A first sealing gasket provided on the mold core is formed with two first concession through holes, the two first concession through holes are respectively connected to the two first connection points; and at least one male mold core, respectively It is arranged in the corresponding second assembly groove and matches with the female mold core, and a second mold core waterway is formed in the male mold core. The Fresnel lens injection molding die device according to claim 1, wherein the first assembling groove is plural and the female mold core is plural; the first cavity has a first main plastic flow channel and plural first branches Plastic flow channels, the plurality of first branched plastic flow channels extend outward from the first main plastic flow channel and communicate with the plurality of first assembly grooves, respectively. The Fresnel lens injection molding die device according to claim 1, wherein the second assembling groove is plural and the male die is plural; the second cavity has a second main plastic flow channel and plural second branches Plastic flow channel, the second main plastic flow channel corresponds to the first main plastic flow channel, the plural second branches The plastic flow channels respectively correspond to the plurality of first branch plastic flow channels, and extend outward from the second main plastic flow channel and communicate with the plurality of second assembly grooves, respectively. The Fresnel lens injection molding die device as described in claim 1, wherein the second mold core waterway of the male mold core is quadrangular, and the two opposite vertices of the second mold core waterway are two second connected points. A second sealing washer is formed through a second sealing washer formed on Renshang, and two second concession through holes are formed therethrough, and the two second concession through holes are respectively connected to the two second communication points. The Fresnel lens injection molding die device according to claim 4, wherein the Fresnel lens injection molding die device further includes a fixed substrate and a movable substrate, the fixed substrate and the mother mold are fixed to each other, and are provided on the fixed substrate There is at least one first mold core pipeline group, each first mold core pipeline group has a first inflow pipe and a first outflow pipe to connect to the two first yielding through holes corresponding to the corresponding female mold core respectively; the movable substrate The male mold is fixed to each other, and at least one second mold core pipeline group is provided on the movable substrate, and each second mold core pipeline group has a second inflow pipe and a second outflow pipe to connect to the corresponding male mold respectively Mo Ren's two second give way through holes. The Fresnel lens injection molding die device according to claim 1, wherein the female mold has a female mold backing block and a female mold outer frame, the at least one first assembling groove and the first mold cavity are formed in the female mold In the liner block, the outer frame of the female mold is hollow and sleeved on the female mold liner. The Fresnel lens injection molding mold device according to claim 1, wherein the male mold has a male mold backing block and a male mold outer frame, the at least one second assembly groove and the second mold cavity are formed in the male mold In the liner block, the outer frame of the male mold is hollow and sleeved on the male mold liner.

Images