KR101662157B1

KR101662157B1 - Injection molding device for lens

Info

Publication number: KR101662157B1
Application number: KR1020150050237A
Authority: KR
Inventors: 최원영
Original assignee: (주)디지탈옵틱
Priority date: 2015-04-09
Filing date: 2015-04-09
Publication date: 2016-10-05

Abstract

Disclosed is a molding apparatus for manufacturing a lens. According to the present invention, the molding apparatus for manufacturing a lens comprises a fixation side mold, and an operation side mold. A center nozzle, and a sprue bush in which a part of the center nozzle is inserted are located on the fixation side mold. The center nozzle has a center hole, and a heater is arranged around the circumference of the center hole. The sprue bush has a bush hole connected to the center hole, and forming a sprue of a molded lens. The molding apparatus can reduce an amount of molded plastic materials, and has a reduced injection molding cycle.

Description

[0001] INJECTION MOLDING DEVICE FOR LENS [0002]

The present invention relates to an injection apparatus for lens production.

In general, plastic optical lenses are used in the form of a lens module, which is used in combination with an instrument (barrel, housing, etc.) which can be manufactured by injection molding or the like. The plastic optical lens is formed by injecting a plastic resin into an injection apparatus including a mold. As shown in Fig. 1, the mold 12 produces not only the lens 12, but also the spool corresponding to the passage through which the plastic resin flows in the mold (14) and a runner (16).

Referring to FIG. 1, it can be seen that the volume of the sprue 14 and the runner 16 is relatively larger than that of the lens 12 to be manufactured by the injection apparatus. Since the sprue 14 and runner 16 are very difficult to reuse later, they are mostly discarded after the lens 12 is detached. This not only increases the material cost for plastic injection molding but also increases the injection time and cooling time since the plastic resin is formed into the lens 12 after passing through the sprue 14 and the runner 16 .

Korean Registered Patent No. 10-1161942

SUMMARY OF THE INVENTION Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and it is an object of the present invention to provide an injection apparatus for lens production capable of reducing plastic injection material.

In addition, the present invention can provide an injection apparatus for lens production capable of reducing an injection molding cycle.

Further, the present invention can provide an injection apparatus for lens production capable of improving the quality of an injection product.

Further, the present invention can provide an injection apparatus for manufacturing a lens that can extend the life of the apparatus.

Other objects of the present invention will become more apparent through the embodiments described below.

According to an aspect of the present invention, there is provided an injection apparatus for manufacturing a lens, comprising a stationary-side mold and a movable-side mold, the stationary-side mold having a center nozzle and a sprue bush for inserting a part of the center nozzle, And a heater is provided around the center hole. The sprue bush has a bush hole having a predetermined length communicating with the center hole and forming a sprue of the lens projection.

The injection apparatus for manufacturing a lens according to the present invention may include one or more of the following embodiments. For example, the center nozzle has a center body, a nozzle tip is formed at the end of the center body, the heater includes a body heater positioned at a portion other than the nozzle tip in the center body, and a tip heater positioned at the center tip .

The sprue bushing has a tip insertion portion having a shape corresponding to the nozzle tip, and a center tip can be inserted into the tip insertion portion.

The tip heater starts to generate heat before mold closing, dissolves the resin located in the center hole to open the center hole, stops heating after completion of the holding pressure, and cures the resin located in the center hole to close the center hole.

The sprue bushing may be formed by a high strength heat resistant copper alloy.

Since the length of the sprue can be shortened in the present invention, it is possible to provide an injection apparatus for lens production capable of saving plastic injection material.

Further, the present invention can provide an injection apparatus for lens production capable of shortening injection molding cycles such as filling, cooling, and mold opening and closing.

In addition, the present invention can provide an injection apparatus for lens production capable of effectively transferring the injection pressure and speed of the injection apparatus to the cavity to improve the quality of the injection product.

In addition, the present invention can provide an injection apparatus for manufacturing a lens that can extend the life of the apparatus because injection is possible using a relatively low pressure.

1 is a perspective view illustrating a lens, a runner, and a sprue manufactured by a conventional injection apparatus.
2 is a cross-sectional view illustrating an injection apparatus for manufacturing a lens according to an embodiment of the present invention.
3 is a cross-sectional view illustrating a center nozzle of the injection apparatus for lens production illustrated in Fig.
4 is a cross-sectional view illustrating a sprue bushing of the injection apparatus for lens production illustrated in Fig.
5 is a perspective view illustrating a lens, a runner, and a sprue produced by an injection apparatus for lens production according to an embodiment of the present invention.
FIG. 6 is a diagram comparing the filling times of the conventional injection molding apparatus for lens production and the injection molding apparatus for lens manufacturing according to the present embodiment.
Fig. 7 is a chart comparing the cooling times of the conventional injection molding apparatus for lens production and the injection molding apparatus for lens production according to the present embodiment, respectively.
FIG. 8 is a view comparing the filling states of the conventional injection molding apparatus for lens manufacturing and the injection molding apparatus for lens manufacturing according to the present embodiment, respectively.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention is capable of various modifications and various embodiments, and specific embodiments are illustrated in the drawings and will be described in detail in the detailed description. It is to be understood, however, that the invention is not to be limited to the specific embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout the specification and claims. The description will be omitted.

2 is a cross-sectional view illustrating an injection apparatus 100 for manufacturing a lens according to an embodiment of the present invention. 3 is a cross-sectional view illustrating a center nozzle 130 of the injection molding apparatus 100 for lens manufacturing illustrated in FIG. 2. FIG. 4 is a cross-sectional view illustrating the center nozzle 130 of the lens manufacturing injection apparatus 100 illustrated in FIG. 150). 5 is a perspective view illustrating a lens mold 101 manufactured by an injection apparatus 100 for lens manufacturing according to an embodiment of the present invention.

Referring to FIGS. 2 to 5, the injection apparatus 100 for manufacturing lenses according to the present embodiment is for manufacturing the lens 102 through the lens insert 101 illustrated in FIG.

The injection apparatus 100 for lens manufacturing according to the present embodiment includes a fixed side mold 110 and a movable side mold 170. [ The movable-side mold 170 is coupled to or separated from the stationary-side mold 110 while moving during mold opening and mold clamping of the mold.

The fixed side mold 110 includes a locate ring 112, a guide plate 116, a fixed side mounting plate 118, and a fixed side mold plate 120. The center nozzle 130 is inserted in the center of the stationary side mounting plate 118 and the stationary side mold plate 120 and the sprue bushing 150 Is inserted.

The injection apparatus 100 for lens manufacturing according to the present embodiment is characterized in that the center nozzle 130 and the sprue bush 150 are used to reduce the length of the sprue 106 in the lens injection molding 101. [ Since the resin melted by the heaters 136 and 142 is injected into the center hole 134 formed in the center nozzle 130 and then injected into the sprue bush 150, The apparatus 100 can shorten the length of the sprue 106 (i.e., the length of the bush hole 154 of the sprue bushing 150).

Since the injection apparatus 100 for lens manufacturing according to the present embodiment is formed to have only a short length without removing the sprue 106 from the lens mold 101, It is possible to remove the lens injection object 101 from the injection apparatus 100 by using the injection molding machine.

The locating ring 112 guides the molten resin injected from the injection nozzle to the center nozzle 130 by guiding the injection nozzle (not shown) for injecting the molten plastic resin. The locate ring 112 has an insertion hole 114 into which the injection nozzle can be inserted.

A guide plate 116 is provided below the locating ring 112. The guide plate 116 is positioned on the fixed side mounting plate 118 so that the locating ring 112 is spaced apart from the fixed side mounting plate 118 by a predetermined distance. Thus, the locate ring 112 is positioned above the center nozzle 130. A nozzle head 146 of the center nozzle 130 is positioned at the center of the guide plate 116.

The fixed side mounting plate 118 is formed in the same size as the fixed side mold plate 120 and the guide plate 116 and corresponds to the movable side mounting plate 188 of the movable side mold 170. A center nozzle 130 is inserted in the center of the fixed side mounting plate 118 and a nozzle head 146 of the center nozzle 130 is seated on the upper surface thereof.

The stationary side mold plate 120 is a portion formed at the center of the lower surface of the cavity 122 for forming the lens mold 101 and a sprue bush 150 is inserted at the center thereof. The entire thickness of the fixed-side mold plate 120 may be formed to be substantially equal to the height of the sprue bushing 150. [ The upper end of the sprue bush 150 inserted into the stationary-side mold plate 120 may be positioned on the same plane as the upper surface of the stationary-side mold plate 120, respectively. The sprue bushing (150) is in direct communication with the cavity (122).

A cavity 122 for forming the runner 104 and the lens 102 of the lens mold 101 is formed on the lower surface of the stationary side mold plate 120. The fixed-side mold plate 120 may have grooves (not shown) through which cooling water (not shown) can flow.

The center nozzle 130 is located over the stationary side mounting plate 118 and the stationary side mold plate 120 and heats the molten resin injected from the injection nozzle to enter the sprue bushing 150 in a non- . The center nozzle 130 includes a nozzle body 132 and a nozzle head 146.

The nozzle body 132 has a cylindrical shape and a center hole 134 corresponding to the movement path of the molten resin is formed at the center of the nozzle body 132. Around the center hole 134, a body heater 136 and a tip And a heater 142 are respectively provided. The tip of the nozzle body 132 is formed with an inclined nozzle tip 138. The nozzle tip 138 is inserted into the tip inserting portion 158 formed in the sprue bushing 150.

The nozzle body 132 has a predetermined length and protrudes from the fixed side mounting plate 118 so that the nozzle tip 138 protrudes to the stationary side mold plate 120. As a result, the length of the sprue bushing 150 is shortened, and as a result, the length of the sprue 106 in the lens extrusion 101 is shortened.

The length of the sprue 106 is shortened in the lens injection object 101, so that the plastic injection material can be saved and the injection molding cycle such as filling, cooling and mold opening and closing can be shortened. In addition, since the length of the sprue 106 is shortened in the lens injection molding 101, the injection pressure and speed of the injection molding machine are effectively transferred to the cavity to improve the quality of the injection molding product, It is possible to extend the lifetime of the device.

In the center of the nozzle body 132, a center hole 134 is formed to extend from one end to the other end of the nozzle body 132. The plastic resin flowing from the injection nozzle is injected into the bush hole 154 of the sprue bushing 150 after passing through the center hole 134. The center hole 134 has the same diameter throughout its lengthwise direction and is not provided with another member such as a valve (not shown) or a pin (not shown).

A body heater 136 and a tip heater 142 are provided around the center hole 134 to prevent the resin passing through the center hole 134 from hardening. The body heater 136 and the tip heater 142 may be formed by a coil heater or the like, and may be independently controlled by a controller (not shown).

Since the tip heater 142 is formed on the nozzle tip 138 through which the plastic resin is injected, when the plastic resin is hardened, it can be melted and the center hole 134 can be opened. In particular, the tip heater 142 may be positioned more closely to the center hole 134 than the body heater 136. The tip heater 142 starts to generate heat before mold closing to melt the resin located in the center hole 134 to open the center hole 134 and to stop the heat generation after the completion of the holding of the pressure, The center hole 134 can be closed.

A temperature sensor (not shown) is provided inside the nozzle body 132 to sense the temperature change by the body heater 136 and the tip heater 142. A controller (not shown) receives the signal of the temperature sensor and can control the temperature and the operation timing of the center nozzle 130.

The nozzle head 146 protrudes outward from the upper portion of the nozzle body 132 and has a cylindrical shape. The nozzle head 146 is seated on the upper surface of the fixed side mounting plate 118 and stably positioned in the center of the guide plate 116.

The lower portion of the center nozzle 130 is directly connected to the sprue bushing 150. The sprue bush 150 corresponds to a portion for forming the sprue 106 in the lens extrudate 101. In the absence of the sprue 106 in the lens extrusion, it is difficult to transport the lens extrusion when the mold is subsequently opened. Therefore, the injection apparatus 100 for manufacturing a lens according to the present embodiment is provided with a center nozzle 130 for reducing the length of the sprue 106, and a sprue bush (not shown) for securing the sprue 106 having a constant length. 150).

The sprue bushing 150 may be formed of a material having a high thermal conductivity so that the heat generated from the tip heater 142 as well as the body heater 136 of the center nozzle 130 can be easily transferred have. Since the sprue bushing 150 does not have its own heater, the molding cycle can be shortened by using the heat generated by the center nozzle 130, and the center nozzle 130 and the stationary-side mold plate 120 The quality of the lens mold 101 can be improved. The sprue bushing 150 may be formed by a high-strength heat-resisting copper alloy steel (HR750, HIT-75, Mold Max).

The sprue bush 150 has a cylindrical bush body 152 and a bushing head 156 formed around the bush body 152 and is inserted into the fixed side mold plate 120.

The bush head 156 protrudes outward from the upper end of the bush body 152 and has a cylindrical shape. A tip inserting portion 158 is formed at the center of the bush head 156 to insert the nozzle tip 138 therein. The tip inserting portion 158 has a shape corresponding to the nozzle tip 138, specifically, a vertical surface 162 and an inclined surface 164 which are continuously formed. The nozzle tip 138 can be stably inserted into the tip inserting portion 158 by the vertical surface 162 and the plastic resin injected from the center hole 134 by the inclined surface 164 can be stably inserted into the tip inserting portion 158. [ And can be stably introduced into the bush hole 154.

The bush body 152 has a diameter smaller than that of the bush head 156 and a bush hole 154 is formed at the center of the bush body 152 so as to be directly connected to the center hole 134 in series. The plastic resin flowing into the bush hole 154 is formed as a sprue 106 in the lens injection object 101. The length of the bush hole 154 may be the same as the length of the sprue 106 in the lens extrudate 101. The injection apparatus 100 for lens manufacturing according to the present embodiment is provided with a center nozzle 130 having a heating function on the upper part of the sprue bushing 150 and a part thereof (nozzle tip 138) 150, the length of the sprue 106 can be made shorter.

The plastic resin that has passed through the bush hole 154 enters the cavities 122 and 175 provided in the fixed side mold plate 120 and the movable side mold plate 172 to form the lens 102 and the runner 104, do.

The length of the bush hole 154 can be adjusted, whereby the length of the sprue 106 can be adjusted in the lens insert 101. If the length of the bush hole 154 is changed, the length of the center nozzle 130 can be changed.

The movable-side mold 170 is moved by a separate driving device (not shown). The movable-side mold 170 includes a movable-side mold plate 172, a receiving plate 176, and a movable-side mounting plate 188.

The cavity 175 in which the lens 102 and the runner 104 of the lens mold 101 are formed is formed in the core 174 located at the center thereof in the movable mold plate 172, And corresponds to the cavity 122 formed in the plate 120. [ A core 174 is provided at the center of the movable mold plate 172. The core 174 is passed through an ejector pin 178.

The support plate 176 corresponds to a plate in contact with the movable-side mold plate 172. An ejector pin 178 for ejecting the lens lens ejection product 101 from the movable side mold plate 172 and an ejector plate 182 for driving the ejector pin 178 are disposed in the inside of the support plate 176. [

The ejector pin 178 pushes up the sprue 106 positioned at the center of the lens ejection 101 shown in Fig. 5 so that the lens ejection 101 is separated from the core 174 of the movable side mold plate 172 . An ejector plate 182 is provided at the rear of the ejector pin 178 and an ejector rod 192 is provided at the rear of the ejector plate 182. The ejector plate 182 and the ejector pin 178 are advanced or retreated by advancing or retreating the ejector rod 192. [

On the rear side of the support plate 176, a movable side mounting plate 188 is provided.

FIGS. 6 to 8 are views comparing the filling time, the cooling time, and the filling state of each of the conventional injection molding apparatus for lens manufacturing and the injection molding apparatus 100 for lens manufacturing according to the present embodiment.

6, when the injection apparatus 100 (right side) according to the present embodiment is used as compared to the conventional injection apparatus (left), it can be seen that the filling time of the plastic resin is shortened by 0.669 seconds from 2.151 seconds to 1.482 seconds . In this way, the length of the sprue 106 is reduced to shorten the filling time of the plastic resin in the mold, thereby shortening the injection cycle and increasing the production efficiency.

Referring to FIG. 7, when the injection apparatus 100 (right side) according to the present embodiment is used as compared to the conventional injection apparatus (left), the cooling time of the plastic resin is shortened by 2.349 seconds from 10.76 seconds to 8.411 seconds . In this way, after the injection is completed, the cooling time before the mold is opened can be shortened, thereby shortening the injection cycle and increasing the production efficiency.

Referring to FIG. 8, when a conventional injection apparatus (left) is used, a point at which the filling state is poor at an end portion of the lens 102 corresponding to the end portion of the lens injection object 101 is found. However, when the injection apparatus 100 (right side) according to the present embodiment is used, injection failure does not occur in the lens 102. As a result, the injection apparatus 100 according to the present embodiment can improve the quality of the lens 102.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. It will be understood that the invention may be varied and varied without departing from the scope of the invention.

100: Injection device for lens production
101: Lens Injection
110: stationary side mold
130: center nozzle
150: Spruce Bush
170: movable side mold

Claims

A fixed side mold and a movable side mold; And
A center nozzle positioned in the stationary-side mold; and a sprue bush in which a part of the center nozzle is inserted,
Wherein the fixed-side mold includes a stationary-side mounting plate and a stationary-side mold plate which are in contact with each other, and a locating ring located at an upper portion of the center nozzle,
Wherein the locating ring includes an insertion hole into which the injection nozzle can be inserted so that the injection nozzle is positively positioned so that the injected molten resin flows into the center nozzle,
The center nozzle includes a center body, a nozzle tip provided at an end of the center body and protruding from the stationary side mold plate, and a center hole formed through the center body and the nozzle tip,
The sprue bush is located on the fixed-side mold plate and is formed of a high-strength heat-resisting copper alloy steel,
Wherein the sprue bush includes a tip inserting portion into which the nozzle tip is inserted and a bush hole communicating with the center hole,
Wherein the tip inserting portion has a shape corresponding to the nozzle tip by having a continuously formed vertical surface and an inclined surface,
A body heater disposed around the center hole of the center nozzle and a tip heater disposed adjacent to the center hole and located at the nozzle tip as compared with the body heater,
The tip heater starts to generate heat before the mold opening and closing, dissolves the resin located in the center hole to open the center hole, stops the heat generation after the completion of the holding pressure, and cures the resin located in the center hole to close the center hole ,
The movable mold includes a core, an ejector pin arranged to penetrate the core and pushing up the sprue of the lens mold to separate the lens mold from the core, an ejector plate coupled with the ejector pin, And an ejector rod for driving the ejector pin and the ejector plate while moving up and down from the rear.

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