Injection molding method for propionate fiber glasses legs

Abstract

The present invention discloses a method for injection molding of propionate fiber glasses legs, which is used for injection molding metal pins into the body of propionate fiber glasses legs, and comprises the following steps: placing propionate fiber raw material into the barrel of an injection molding machine, placing metal pins into an injection mold; positioning the metal pins using a positioning device on the injection mold; starting the injection molding machine, and injecting the molten propionate fiber raw material into the glasses leg molding cavity of the injection mold through the injection molding machine; and opening the mold to take out the injection molded glasses legs after the injection mold is cooled. The present invention replaces the mold making machine with a high-precision injection mold, which has a more stable shape, good hardness, and better quality, and greatly reduces production costs and improves production efficiency. Glasses legs of different colors can also be obtained by matching the color of the propionate fiber raw material, and the colors are arbitrary and adjustable in multiple colors.

Description

Technical Field

[0001] The invention relates to the technical field of glasses, and in particular to an injection molding method for propionate fiber glasses legs. Background Art

[0002] There are many types of glasses and various materials. Among them, plate glasses frames are light in weight, hard, glossy, beautiful in style, not easy to deform and discolor, and durable, so they are becoming more and more popular.

[0003] The materials of sheet glasses frames are mainly acetate fiber and CP propionate fiber. The hydroxyl group in the CP propionate cellulose molecule is a polymer in propionic acid, so it has good weather resistance and low temperature resistance, and has gradually become the main material for high-end frames.

[0004] There are two manufacturing processes for CP cellulose propionate glasses legs: injection molding and pressing and polishing. For example, Chinese invention patent CN209842252 U discloses a propionate fiber (CP) injection molded glasses frame, including a body and glasses legs, the body includes a propionate fiber frame, the propionate fiber frame includes a left frame and a right frame, and the outer wall of the left frame and the right frame are both provided with a connector on one side. When the glasses are in use, the two glasses legs are moved left and right, and the glasses legs slide left and right under the action of the connector. When they reach perpendicular to the frame, such an angle is very suitable and convenient for wearing glasses. A rubber sleeve is also provided on one side of the glasses leg, that is, the wearing part of the organ, and a nose pad is also provided on one side of the rectangular outer wall of the frame. Such a setting can make it more comfortable to wear. In this scheme, all the glasses legs are directly injection molded by CP propionate fibers. Since no metal pins are inserted into the glasses legs, the strength and elasticity need to be further improved.

[0005] At present, CP propionate fiber glasses legs are usually inserted with metal pins by a punching machine. The main production process includes: after the plate is cut by a pressing plate, it is baked for 72-120 hours, and then the metal pins are punched into the plate softened by a high-frequency machine by a punching machine. Due to the high temperature of the punching machine, the working environment of the operator is poor, and only one strip can be punched at a time, which has low work efficiency; in addition, the glasses legs produced by this production process have large deviations, instability, and high scrap rate. After the punching is completed, it needs to go through many processes such as planing, scraping, and cleaning glue, which has a long production cycle.

[0006] The biggest difficulty in the process of using metal pins and CP propionate fiber for integrated injection molding is that it is difficult to accurately position the metal pins in the mold, resulting in a high scrap rate, increased production costs, and especially the inability to achieve mass production.

[0007] In view of this, it is urgent to improve the existing CP propionate fiber glasses leg injection molding process to reduce the scrap rate, reduce costs, and be suitable for mass production. Summary of the invention

[0008] In view of the above-mentioned defects, the technical problem to be solved by the present invention is to provide an injection molding method for propionate fiber glasses legs, so as to solve the problems of the existing technology that the production of propionate fiber glasses legs has a high scrap rate, high production cost and cannot be mass-produced.

[0009] To this end, the present invention provides a method for molding propionate fiber injection-molded glasses legs, which is used to injection-mold a metal pin into a propionate fiber glasses leg body, comprising the following steps:

[0010] Put the propionate fiber raw material into the barrel of the injection molding machine, and put the metal pin into the injection mold;

[0011] Positioning the metal pin using a positioning device on the injection mold;

[0012] The injection molding machine is started, and the molten propionate fiber raw material is injected into the eyeglass leg molding cavity of the injection mold through the injection molding machine;

[0013] After the injection mold is cooled, the mold is opened to take out the injection-molded glasses legs.

[0014] In the above scheme, preferably, glasses legs of different colors are obtained by matching the colors of the propionate fiber raw material.

[0015] In the above solution, preferably, the metal pin includes:

[0016] The pin body is used for injection molding inside the propionate fiber glasses leg body;

[0017] A connector is arranged at the front end of the pin body, the front end of the connector has a protruding portion protruding inwardly from the propionate fiber glasses leg body, the front end of the protruding portion is provided with a hinge for connecting with the head of the glasses, and the protruding portion is provided with a plurality of positioning holes running longitudinally;

[0018] The positioning device is a positioning wire, which passes through the positioning hole to realize the positioning of the metal pin.

[0019] In the above scheme, preferably, the heating temperature of the unloading zone of the injection molding machine is 235 degrees Celsius, the heating temperature of the injection molding zone of the injection mold is 200-225 degrees Celsius, the injection pressure of the injection mold is 70-80Mpa, and the flow rate is 10-20m / s.

[0020] In the above scheme, preferably, the injection mold is provided with a plurality of temple molding cavities arranged side by side, the plurality of metal pins are respectively placed in the corresponding temple molding cavities, and the coaxial positioning holes on the plurality of metal pins are fixed by the same positioning line.

[0021] In the above scheme, preferably, the positioning line is threaded with a crochet hook, and one end of the positioning line is fixed to one end of the injection mold, and the other end is detachably hooked on the other end of the injection mold.

[0022] In the above solution, preferably, the pin body is a cylinder, and the front portion is flattened into a flat sheet-like front plate.

[0023] In the above solution, preferably, the inner side surface of the front end of the front piece is a smooth plane, and the upper, lower side surfaces and outer side surfaces are rough surfaces.

[0024] In the above solution, preferably, the inner side surface of the transition connection portion between the front plate and the cylinder is provided with a plurality of longitudinal convex grooves.

[0025] In the above solution, preferably, the longitudinal groove is a V-shaped groove.

[0026] It can be seen from the above technical scheme that the injection molding method of the propionate fiber glasses leg provided by the present invention uses the propionate fiber raw material and the metal pin for integral injection molding. Compared with the prior art, the present invention has the following beneficial effects:

[0027] First of all, high-precision injection molds were used to replace the mold making machines, which have more stable shape, better hardness, and better quality. They also greatly reduced production costs and improved production efficiency.

[0028] Secondly, in a preferred embodiment of the present invention, glasses legs of different colors can be obtained by color matching the propionate fiber raw material, and the colors are arbitrary and adjustable in multiple colors.

[0029] Third, the metal pin connector is provided with a positioning hole, which can accurately locate its position in the injection mold, thereby improving the yield rate and further reducing the cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces and describes the drawings required for use in the embodiments of the present invention or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0031] Figure 1 A flow chart of the injection molding method of the propionate fiber glasses leg provided by the present invention;

[0032] Figure 2 is a schematic diagram of the temple of the glasses in the present invention;

[0033] Figure 3 is a schematic diagram of a metal pin in the present invention;

[0034] Figure 4 It is a schematic diagram of mass production of glasses legs in the present invention.

[0035] Figure 1-Figure 4 In the figure, the corresponding relationship of the parts is as follows:

[0036] Metal pin 210, glasses leg body 220;

[0037] Rough surface 223 , longitudinal groove 224 , protrusion 225 , hinge 226 , positioning hole 227 . DETAILED DESCRIPTION

[0038] The following will be combined with the accompanying drawings of the embodiments of the present invention to clearly and completely describe the technical solutions of the embodiments of the present invention. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0039] The implementation principle of the present invention is: color matching of propionate fiber raw materials is performed through the barrel of an injection molding machine, a metal pin is placed in an injection mold and positioned, the injection molding machine is started, and the molten propionate fiber raw materials are injected into the eyeglass leg molding cavity of the injection mold through the injection molding machine to obtain the eyeglass leg by injection molding. Thus, production efficiency is improved, scrap rate is reduced, and production cost is reduced.

[0040] In order to more clearly explain and illustrate the technical solution and implementation of the present invention, several preferred specific embodiments for implementing the technical solution of the present invention are introduced below.

[0041] It should be noted that the directional words such as "inside, outside", "front, back" and "left, right" in this article are expressed based on the product usage status. Obviously, the use of the corresponding directional words does not constitute a limitation on the protection scope of this scheme.

[0042] See also Figure 1 , Figure 1 This is a flow chart of the injection molding method of the propionate fiber glasses legs provided by the present invention.

[0043] like Figure 1 As shown, the injection molding method of the propionate fiber glasses leg provided by the present invention comprises the following steps:

[0044] Step 110: Place the propionate fiber raw material into the barrel of the injection molding machine, and place the metal pin into the injection mold.

[0045] In this step, the color of the propionate fiber raw material can be matched to obtain glasses legs of different colors. Therefore, the color of the glasses legs can be adjusted as desired by the method of the present invention, and multiple colors can be adjusted very conveniently.

[0046] Step 120: Use the positioning device on the injection mold to position the metal pin.

[0047] The precise positioning of the metal pin is the key to ensuring the yield of the product. Traditional glasses legs usually have only one hinge hole, which cannot achieve precise positioning. For this reason, a clamp is needed, which makes the fixture complex and the tooling cost high.

[0048] The method provided by the present invention provides a positioning hole on the connector of the metal pin, and can accurately locate its position in the injection mold through a positioning wire, without the need for a complex clamping device, thereby reducing tooling costs and improving the yield rate.

[0049] Step 130: Start the injection molding machine, and inject the molten propionate fiber raw material into the eyeglass leg molding cavity of the injection mold through the injection molding machine.

[0050] In this step, the heating temperature of the unloading zone of the injection molding machine is 235 degrees Celsius, the heating temperature of the injection molding zone of the injection mold is 200-225 degrees Celsius, the injection pressure of the injection mold is 70-80Mpa, and the flow rate is 10-20m / s.

[0051] Step 140: After the injection mold is cooled, the mold is opened to take out the injection-molded glasses legs.

[0052] After that, cut off the water outlet, grind it, and roll it with water to shape it.

[0053] In the above method, if Figure 2 , Figure 3 As shown, the temple of the glasses is made by using a propionate fiber injection molding process, and includes a metal pin 210 and a propionate fiber temple body 220 which is injection-molded and wrapped around the outer surface of the metal pin 210 .

[0054] The metal pin includes a pin body and a connector. The pin body is used for injection molding inside the propionate fiber temple body. On the one hand, it improves the strength of the temple body 220, and on the other hand, it provides stronger elasticity, so that it is not easy to loosen after the user wears it.

[0055] The pin body is a cylinder, and the front part is flattened into a flat sheet-like front piece, the inner side surface of the front end of the front piece is a smooth plane, and the upper, lower and outer sides are rough surfaces 223. The inner side surface of the transition connection between the front piece and the rear cylinder is provided with a plurality of longitudinal convex grooves 224, which are V-shaped grooves, thereby providing greater elastic restoring force, so that the temples of the glasses have greater elasticity.

[0056] The connector is arranged on the inner side of the front piece of the pin body and can be fixed by welding. The front end of the connector has a protrusion 225 protruding inwardly from the propionate fiber eyeglass leg body. The protrusion 225 is in the shape of a rectangular column, and the inner side of the rear end is in the shape of an inward concave arc. The front end of the protrusion 225 is provided with a hinge 226 for connecting with the pile head of the eyeglass frame, and the protrusion 223 is provided with a plurality of positioning holes 227 that penetrate longitudinally.

[0057] The method provided by the present invention can also be conveniently carried out in batch production, specifically:

[0058] like Figure 4 As shown, the injection mold is provided with a plurality of temple molding cavities arranged side by side, and a plurality of metal pins 210 are respectively placed in the corresponding temple molding cavities, and the coaxial positioning holes on the plurality of metal pins are fixed by the same positioning line 230. Therefore, the plurality of metal pins 210 can be simultaneously positioned in a plurality of injection molds for batch production by the positioning line 230.

[0059] The positioning wire can be threaded with a hook, one end of the positioning wire is fixed to one end of the injection mold, and the other end is detachably hooked to the other end of the injection mold. After the glasses leg is injection molded, the end of the positioning wire is removed from the other end of the injection mold, and the positioning wire is pulled out to open the mold and remove the glasses leg.

[0060] Based on the description of the above specific embodiments, the glasses and the glasses leg structure formed by propionate fiber injection molding provided by the present invention have the following advantages compared with the prior art:

[0061] First, the use of propionate fiber raw materials and metal pins for integrated injection molding is 5 times faster than the traditional method of inserting metal pins with a spleen punching machine, and the cost is reduced by 1 / 3, which greatly reduces the production cost and improves the production efficiency. In addition, the shape is more stable, the hardness is better, and the quality is better. The color of the propionate fiber raw material is easy to adjust and can be combined at will.

[0062] Secondly, the metal pin connector is provided with a positioning hole, which can accurately locate its position in the injection mold, thereby improving the yield rate and further reducing the cost.

[0063] Third, the front part of the metal pin is flattened to form a flat front piece, the inner side of the front end of the front piece is a smooth plane, and the upper, lower and outer sides are rough surfaces. The inner side of the transition connection between the front piece and the rear cylinder is provided with a plurality of longitudinal convex grooves, which are V-shaped grooves, thereby providing greater firmness and elastic recovery force, so that the temples of the glasses have greater elasticity.

[0064] Finally, it should be noted that the terms "comprises", "includes" or any other variants thereof as used herein are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the phrase "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0065] The present invention is not limited to the above-mentioned optimal implementation mode. Anyone should be aware that any structural changes made under the inspiration of the present invention, and any technical solutions that are the same or similar to the present invention, fall within the protection scope of the present invention.

Claims

1. A method for injection molding of a propionate fiber glasses leg, the method being used to injection mold a metal pin into a propionate fiber glasses leg body, characterized in that: The following steps are involved: Put the propionate fiber raw material into the barrel of the injection molding machine, and put the metal pin into the injection mold; Positioning the metal pin using a positioning device on the injection mold; The injection molding machine is started, and the molten propionate fiber raw material is injected into the eyeglass leg molding cavity of the injection mold through the injection molding machine; After the injection mold is cooled, the mold is opened to take out the injection-molded glasses legs; The metal pin comprises: The pin body is used for injection molding inside the propionate fiber glasses leg body; A connector is arranged at the front end of the pin body, the front end of the connector has a protruding portion protruding inwardly from the propionate fiber glasses leg body, the front end of the protruding portion is provided with a hinge for connecting with the head of the glasses, and the protruding portion is provided with a plurality of positioning holes running longitudinally; The positioning device is a positioning wire, which passes through the positioning hole to realize the positioning of the metal pin.

2. The method according to claim 1, characterized in that The glasses legs of different colors are obtained by matching the colors of the propionate fiber raw material.

3. The method according to claim 1, characterized in that The heating temperature of the material discharge zone of the injection molding machine is 235 degrees Celsius, the heating temperature of the injection molding zone of the injection mold is 200-225 degrees Celsius, the injection pressure of the injection mold is 70-80Mpa, and the flow rate is 10-20m / s.

4. The method according to claim 1, characterized in that The injection mold is provided with a plurality of eyeglass leg forming cavities arranged side by side, and the plurality of metal pins are respectively placed in the corresponding eyeglass leg forming cavities, and the coaxial positioning holes on the plurality of metal pins are fixed by the same positioning line.

5. The method according to claim 4, characterized in that The positioning line is threaded by a crochet hook, and one end of the positioning line is fixed to one end of the injection mold, and the other end is detachably hooked on the other end of the injection mold.

6. The method according to claim 1, characterized in that The pin body is a cylinder, and the front portion is flattened into a flat sheet-like front plate.

7. The method according to claim 6, characterized in that: The inner side surface of the front end of the front piece is a smooth plane, and the upper and lower side surfaces and the outer side surface are rough surfaces.

8. The method according to claim 6, characterized in that The inner side surface of the transition connection portion between the front plate and the cylinder is provided with a plurality of longitudinal convex grooves.

9. The method according to claim 8, characterized in that The longitudinal convex groove is a V-shaped groove.

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